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Is Hirschsprung disease a mendelian or a multifactorial disorder?
Coding sequence mutations in RET, GDNF, EDNRB, EDN3, and SOX10 are involved in the development of Hirschsprung disease. The majority of these genes was shown to be related to Mendelian syndromic forms of Hirschsprung's disease, whereas the non-Mendelian inheritance of sporadic non-syndromic Hirschsprung disease proved to be complex; involvement of multiple loci was demonstrated in a multiplicative model.
Hirschsprung disease (HSCR), or congenital intestinal aganglionosis, is a common hereditary disorder causing intestinal obstruction, thereby showing considerable phenotypic variation in conjunction with complex inheritance. Moreover, phenotypic assessment of the disease has been complicated since a subset of the observed mutations is also associated with several additional syndromic anomalies. Coding sequence mutations in e.g. RET, GDNF, EDNRB, EDN3, and SOX10 lead to long-segment (L-HSCR) as well as syndromic HSCR but fail to explain the transmission of the much more common short-segment form (S-HSCR). Furthermore, mutations in the RET gene are responsible for approximately half of the familial and some sporadic cases, strongly suggesting, on the one hand, the importance of non-coding variations and, on the other hand, that additional genes involved in the development of the enteric nervous system still await their discovery. For almost all of the identified HSCR genes incomplete penetrance of the HSCR phenotype has been reported, probably due to modifier loci. Therefore, HSCR has become a model for a complex oligo-/polygenic disorder in which the relationship between different genes creating a non-mendelian inheritance pattern still remains to be elucidated. Hirschsprung's disease is characterized by the absence of ganglion cells in the myenteric and submucosal plexuses of the gastrointestinal tract. Genetic dissection was successful as nine genes and four loci for Hirschsprung's disease susceptibility were identified. Different approaches were used to find these loci such as classical linkage in large families, identity by descent mapping in an inbred kindred, candidate gene approaches based on naturally occurring mutant mice models, and finally the use of model-free linkage and association analyzes. In this study, we review the identification of genes and loci involved in the non-syndromic common form and syndromic Mendelian forms of Hirschsprung's disease. The majority of the identified genes are related to Mendelian syndromic forms of Hirschsprung's disease. The non-Mendelian inheritance of sporadic non-syndromic Hirschsprung's disease proved to be complex; involvement of multiple loci was demonstrated in a multiplicative model. We discuss the practical implications of the elucidation of genes associated with Hirschsprung's disease susceptibility for genetic counseling. Finally, we speculate on possible strategies to identify new genes for Hirschsprung's disease. The major gene for Hirschsprung disease (HSCR) encodes the receptor tyrosine kinase RET. In a study of 690 European- and 192 Chinese-descent probands and their parents or controls, we demonstrate the ubiquity of a >4-fold susceptibility from a C-->T allele (rs2435357: p = 3.9 x 10(-43) in European ancestry; p = 1.1 x 10(-21) in Chinese samples) that probably arose once within the intronic RET enhancer MCS+9.7. With in vitro assays, we now show that the T variant disrupts a SOX10 binding site within MCS+9.7 that compromises RET transactivation. The T allele, with a control frequency of 20%-30%/47% and case frequency of 54%-62%/88% in European/Chinese-ancestry individuals, is involved in all forms of HSCR. It is marginally associated with proband gender (p = 0.13) and significantly so with length of aganglionosis (p = 7.6 x 10(-5)) and familiality (p = 6.2 x 10(-4)). The enhancer variant is more frequent in the common forms of male, short-segment, and simplex families whereas multiple, rare, coding mutations are the norm in the less common and more severe forms of female, long-segment, and multiplex families. The T variant also increases penetrance in patients with rare RET coding mutations. Thus, both rare and common mutations, individually and together, make contributions to the risk of HSCR. The distribution of RET variants in diverse HSCR patients suggests a "cellular-recessive" genetic model where both RET alleles' function is compromised. The RET allelic series, and its genotype-phenotype correlations, shows that success in variant identification in complex disorders may strongly depend on which patients are studied. Hirschsprung's disease (HSCR) is a fairly frequent cause of intestinal obstruction in children. It is characterized as a sex-linked heterogonous disorder with variable severity and incomplete penetrance giving rise to a variable pattern of inheritance. Although Hirschsprung's disease occurs as an isolated phenotype in at least 70% of cases, it is not infrequently associated with a number of congenital abnormalities and associated syndromes, demonstrating a spectrum of congenital anomalies. Certain of these syndromic phenotypes have been linked to distinct genetic sites, indicating underlying genetic associations of the disease and probable gene-gene interaction, in its pathogenesis. These associations with HSCR include Down's syndrome and other chromosomal anomalies, Waardenburg syndrome and other Domit sensorineural deafness, the Congenital Central Hypoventilation and Mowat-Wilson and other brain-related syndromes, as well as the MEN2 and other tumour associations. A number of other autosomal recessive syndromes include the Shah-Waardenburg, the Bardet-Biedl and Cartilage-hair hypoplasia, Goldberg-Shprintzen syndromes and other syndromes related to cholesterol and fat metabolism among others. The genetics of Hirschsprung's disease are highly complex with the majority of known genetic sites relating to the main susceptibility pathways (RET an EDNRB). Non-syndromic non-familial, short-segment HSCR appears to represent a non-Mendelian condition with variable expression and sex-dependent penetrance. Syndromic and familial forms, on the other hand, have complex patterns of inheritance and being reported as autosomal domit, recessive and polygenic patterns of inheritance. The phenotypic variability and incomplete penetrance observed in Hirschsprung's disease could also be explained by the involvement of modifier genes, especially in its syndromic forms. In this review, we look at the chromosomal and Mendelian associations and their underlying signalling pathways, to obtain a better understanding of the pathogenetic mechanisms involved in developing aganglionosis of the distal bowel.
List signaling molecules (ligands) that interact with the receptor EGFR?
The 7 known EGFR ligands are: epidermal growth factor (EGF), betacellulin (BTC), epiregulin (EPR), heparin-binding EGF (HB-EGF), transforming growth factor-α [TGF-α], amphiregulin (AREG) and epigen (EPG).
Autocrine, paracrine, and juxtacrine are recognized modes of action for mammalian EGFR ligands including EGF, TGF-α (TGFα), amphiregulin (AREG), heparin-binding EGF-like growth factor (HB-EGF), betacellulin, epiregulin, and epigen. We identify a new mode of EGFR ligand signaling via exosomes. Human breast and colorectal cancer cells release exosomes containing full-length, signaling-competent EGFR ligands. Exosomes isolated from MDCK cells expressing individual full-length EGFR ligands displayed differential activities; AREG exosomes increased invasiveness of recipient breast cancer cells 4-fold over TGFα or HB-EGF exosomes and 5-fold over equivalent amounts of recombit AREG. Exosomal AREG displayed significantly greater membrane stability than TGFα or HB-EGF. An average of 24 AREG molecules are packaged within an individual exosome, and AREG exosomes are rapidly internalized by recipient cells. Whether the composition and behavior of exosomes differ between nontransformed and transformed cells is unknown. Exosomes from DLD-1 colon cancer cells with a mutant KRAS allele exhibited both higher AREG levels and greater invasive potential than exosomes from isogenically matched, nontransformed cells in which mutant KRAS was eliminated by homologous recombination. We speculate that EGFR ligand signaling via exosomes might contribute to diverse cancer phenomena such as field effect and priming of the metastatic niche. BACKGROUND: In this study the total and phosphorylated amount of epidermal growth factor receptor 1 (EGFR) and 2 (HER2) were measured together with EGFR ligands in tissue samples of breast cancer patients in order to investigate interrelations and possible prognostic values. METHODS: Samples of maligt and non-cancer autologous reference tissue were collected from 415 breast cancer patients. The tissue samples were cut and either paraffin-embedded or homogenized in a lysis buffer to extract the proteins. HER2 was measured using both immunohistochemistry (IHC)/fluorescence in situ hybridization (FISH) and ADVIA Centaur. Phosphorylated HER2 and EGFR (pHER2, pEGFR), total EGFR and the ligands: epidermal growth factor (EGF), transforming growth factor-α (TGFα), amphiregulin (AREG), heparin-binding EGF-like growth factor (HB-EGF), betacellulin (BTC) and epiregulin (EREG) were measured using the Luminex. RESULTS: The HER2 positivity rate was determined to be 25.2% by the Centaur method vs. 15.8% by IHC and FISH. HER2, HB-EGF, TGFα and AREG were upregulated in cancer tissue as compared with autologous reference tissue while EGFR, pEGFR and EGF were downregulated (p<10-6). pEGFR in autologous reference tissue was negatively correlated to the number of positive lymph nodes and to the tumor size (p=0.0007 and p=0.001, respectively) and furthermore, decreased in the group of mastectomy operated patients as compared with the lumpectomy group (p<10-6). HB-EGF in cancer tissue was positively associated with high grade tumors (p<10-6) and pHER2, HB-EGF and BTC were associated with poor disease free survival (p=0.017, p=0.012 and p=0.0026, respectively). CONCLUSIONS: Our study demonstrated a profound activation of the EGFR system. HB-EGF was increased by factor 10 in cancer tissue and related to the biological aggressiveness of the tumors, and pHER2, HB-EGF and BTC were associated with poor clinical outcome. PURPOSE: Although KRAS mutation has been identified as a negative predictive biomarker of anti-EGFR antibodies in metastatic colorectal cancer (mCRC), the efficacy in mCRC patients with KRAS wild-type status remains limited. Anti-EGFR antibodies work by blocking ligand binding, but the significance of EGFR ligands in mCRC has not been completely described. This study was conducted to identify the correlation between all seven EGFR ligands and clinical outcomes in mCRC treated with anti-EGFR antibodies. Furthermore, we determined an appropriate predictive strategy for anti-EGFR antibodies using these EGFR ligands. METHODS: Among 36 mCRC patients who had been treated with cetuximab or panitumumab, we identified 26 mCRC patients with wild-type KRAS status treated properly as the second and further lines and analyzed the relationship between immunoreactivity to seven EGFR ligands and clinical outcomes. RESULTS: Good clinical outcomes were associated with immunoreactivity against amphiregulin (AR), heparin-binding epidermal growth factor (HB-EGF), transforming growth factor-α (TGF-α), and epiregulin (EREG). Further, patients with immunoreactivity to greater than two of these four ligands (AR, HB-EGF, TGF-α, and EREG) had significantly higher response rate (53.3 vs. 0.0 %, p = 0.004) and disease control rate (93.3 vs. 9.0 %, p = 0.00002) and longer progression-free survival (median PFS: 231 vs. 79 days, p = 0.000008), when compared with patients with immunoreactivity against zero or one ligand. CONCLUSIONS: Immunohistochemical analysis of four EGFR ligands (AR, HB-EGF, TGF-α, and EREG) might be a novel predictive biomarker and may help optimize patient selection for cetuximab and panitumumab therapy in patients with mCRC. Prolidase, also known as Xaa-Pro dipeptidase or peptidase D (PEPD), is a ubiquitously expressed cytosolic enzyme that hydrolyzes dipeptides with proline or hydroxyproline at the carboxyl terminus. In this article, however, we demonstrate that PEPD directly binds to and activates epidermal growth factor receptor (EGFR), leading to stimulation of signaling proteins downstream of EGFR, and that such activity is neither cell-specific nor dependent on the enzymatic activity of PEPD. In line with the pro-survival and pro-proliferation activities of EGFR, PEPD stimulates DNA synthesis. We further show that PEPD activates EGFR only when it is present in the extracellular space, but that PEPD is released from injured cells and tissues and that such release appears to result in EGFR activation. PEPD differs from all known EGFR ligands in that it does not possess an epidermal growth factor (EGF) motif and is not synthesized as a transmembrane precursor, but PEPD binding to EGFR can be blocked by EGF. In conclusion, PEPD is a ligand of EGFR and presents a novel mechanism of EGFR activation. The epidermal growth factor receptor (EGFR) is a member of the receptor tyrosine kinase family that plays a role in multiple cellular processes. Activation of EGFR requires binding of a ligand on the extracellular domain to promote conformational changes leading to dimerization and transphosphorylation of intracellular kinase domains. Seven ligands are known to bind EGFR with affinities ranging from sub-omolar to near micromolar dissociation constants. In the case of EGFR, distinct conformational states assumed upon binding a ligand is thought to be a determining factor in activation of a downstream signaling network. Previous biochemical studies suggest the existence of both low affinity and high affinity EGFR ligands. While these studies have identified functional effects of ligand binding, high-resolution structural data are lacking. To gain a better understanding of the molecular basis of EGFR binding affinities, we docked each EGFR ligand to the putative active state extracellular domain dimer and 25.0 ns molecular dynamics simulations were performed. MM-PBSA/GBSA are efficient computational approaches to approximate free energies of protein-protein interactions and decompose the free energy at the amino acid level. We applied these methods to the last 6.0 ns of each ligand-receptor simulation. MM-PBSA calculations were able to successfully rank all seven of the EGFR ligands based on the two affinity classes: EGF>HB-EGF>TGF-α>BTC>EPR>EPG>AR. Results from energy decomposition identified several interactions that are common among binding ligands. These findings reveal that while several residues are conserved among the EGFR ligand family, no single set of residues determines the affinity class. Instead we found heterogeneous sets of interactions that were driven primarily by electrostatic and Van der Waals forces. These results not only illustrate the complexity of EGFR dynamics but also pave the way for structure-based design of therapeutics targeting EGF ligands or the receptor itself. Aberrant epidermal growth factor receptor (EGFR) expression promotes the pathogenesis of maligt peripheral nerve sheath tumors (MPNSTs), the most common maligcy associated with neurofibromatosis type 1, but the mechanisms by which EGFR expression promotes MPNST pathogenesis are poorly understood. We hypothesized that inappropriately expressed EGFRs promote MPNST invasion and found that these kinases are concentrated in MPNST invadopodia in vitro. Epidermal growth factor receptor knockdown inhibited the migration of unstimulated MPNST cells in vitro, and exogenous EGF further enhanced MPNST migration in a substrate-specific manner, promoting migration on laminin and, to a lesser extent, collagen. In this setting, EGF acts as a chemotactic factor. We also found that the 7 known EGFR ligands (EGF, betacellulin, epiregulin, heparin-binding EGF, transforming growth factor-α [TGF-α], amphiregulin, and epigen) variably enhanced MPNST migration in a concentration-dependent manner, with TGF-α being particularly potent. With the exception of epigen, these factors similarly promoted the migration of nonneoplastic Schwann cells. Although transcripts encoding all 7 EGFR ligands were detected in human MPNST cells and tumor tissues, only TGF-α was consistently overexpressed and was found to colocalize with EGFR in situ. These data indicate that constitutive EGFR activation, potentially driven by autocrine or paracrine TGF-α signaling, promotes the aggressive invasive behavior characteristic of MPNSTs. The epidermal growth factor receptor (EGFR) is frequently expressed in triple-negative breast cancer (TNBC) and is a marker of poor prognosis in this patient population. Because activating mutations in this kinase are very rare events in breast cancer, we screened breast tumor gene expression profiles to examine the distribution of EGFR ligand expression. Of the six known EGFR ligands, transforming growth factor alpha (TGFα) was expressed more highly in triple-negative breast tumors than in tumors of other subtypes. TGFα is synthesized as a transmembrane precursor requiring tumor necrosis factor alpha converting enzyme (TACE)/ADAM17-dependent proteolytic release to activate its receptor. In our study, we show that an inhibitor of this proteolytic release blocks invasion, migration and colony formation by several TNBC cell lines. Each of the effects of the drug was reversed upon expression of a soluble TGFα mutant that does not require TACE activity, implicating this growth factor as a key metalloproteinase substrate for these phenotypes. Together, these data demonstrate that TACE-dependent TGFα shedding is a key process driving EGFR activation and subsequent proliferation and invasion in TNBC cell lines. Intrahepatic cholangiocarcinoma (CCA) is characterized by an abundant desmoplastic environment. Poor prognosis of CCA has been associated with the presence of alpha-smooth muscle actin (α-SMA)-positive myofibroblasts (MFs) in the stroma and with the sustained activation of the epidermal growth factor receptor (EGFR) in tumor cells. Among EGFR ligands, heparin-binding epidermal growth factor (HB-EGF) has emerged as a paracrine factor that contributes to intercellular communications between MFs and tumor cells in several cancers. This study was designed to test whether hepatic MFs contributed to CCA progression through EGFR signaling. The interplay between CCA cells and hepatic MFs was examined first in vivo, using subcutaneous xenografts into immunocompromised mice. In these experiments, cotransplantation of CCA cells with human liver myofibroblasts (HLMFs) increased tumor incidence, size, and metastatic dissemination of tumors. These effects were abolished by gefitinib, an EGFR tyrosine kinase inhibitor. Immunohistochemical analyses of human CCA tissues showed that stromal MFs expressed HB-EGF, whereas EGFR was detected in cancer cells. In vitro, HLMFs produced HB-EGF and their conditioned media induced EGFR activation and promoted disruption of adherens junctions, migratory and invasive properties in CCA cells. These effects were abolished in the presence of gefitinib or HB-EGF-neutralizing antibody. We also showed that CCA cells produced transforming growth factor beta 1, which, in turn, induced HB-EGF expression in HLMFs. CONCLUSION: A reciprocal cross-talk between CCA cells and myofibroblasts through the HB-EGF/EGFR axis contributes to CCA progression. PURPOSE: The aim of this study was to investigate the biological and clinical significance of epidermal growth factor receptor (EGFR) signaling pathway in follicular dendritic cell sarcoma (FDC-S). EXPERIMENTAL DESIGN: Expression of EGFR and cognate ligands as well as activation of EGFR signaling components was assessed in clinical samples and in a primary FDC-S short-term culture (referred as FDC-AM09). Biological effects of the EGFR antagonists cetuximab and panitumumab and the MEK inhibitor UO126 on FDC-S cells were determined in vitro on FDC-AM09. Direct sequencing of KRAS, BRAF, and PI3KCA was conducted on tumor DNA. RESULTS: We found a strong EGFR expression on dysplastic and neoplastic FDCs. On FDC-AM09, we could show that engagement of surface EGFR by cognate ligands drives the survival and proliferation of FDC-S cells, by signaling to the nucleus mainly via MAPK and STAT pathways. Among EGFR ligands, heparin-binding EGF-like growth factor, TGF-α and Betacellulin (BTC) are produced in the tumor microenvironment of FDC-S at RNA level. By extending this finding at protein level we found that BTC is abundantly produced by FDC-S cells and surrounding stromal cells. Finally, direct sequencing of tumor-derived genomic DNA showed that mutations in KRAS, NRAS, BRAF, and PI3KCA, which predicts resistance to anti-EGFR MoAb in other cancer models, are not observed in FDC-S. CONCLUSION: Activation of EGFR by cognate ligands produced in the tumor microenvironment sustain viability and proliferation of FDC-S indicating that the receptor blockade might be clinically relevant in this neoplasm. Based on gene expression patterns, breast cancers can be divided into subtypes that closely resemble various developmental stages of normal mammary epithelial cells (MECs). Thus, understanding molecular mechanisms of MEC development is expected to provide critical insights into initiation and progression of breast cancer. Epidermal growth factor receptor (EGFR) and its ligands play essential roles in normal and pathological mammary gland. Signals through EGFR is required for normal mammary gland development. Ligands for EGFR are over-expressed in a significant proportion of breast cancers, and elevated expression of EGFR is associated with poorer clinical outcome. In the present study, we examined the effect of signals through EGFR on MEC differentiation using the human telomerase reverse transcriptase (hTERT)-immortalized human stem/progenitor MECs which express cytokeratin 5 but lack cytokeratin 19 (K5(+)K19(-) hMECs). As reported previously, these cells can be induced to differentiate into luminal and myoepithelial cells under appropriate culture conditions. K5(+)K19(-) hMECs acquired distinct cell fates in response to EGFR ligands epidermal growth factor (EGF), amphiregulin (AREG) and transforming growth factor alpha (TGFα) in differentiation-promoting MEGM medium. Specifically, presence of EGF during in vitro differentiation supported development into both luminal and myoepithelial lineages, whereas cells differentiated only towards luminal lineage when EGF was replaced with AREG. In contrast, substitution with TGFα led to differentiation only into myoepithelial lineage. Chemical inhibition of the MEK-Erk pathway, but not the phosphatidylinositol 3-kinase (PI3K)-AKT pathway, interfered with K5(+)K19(-) hMEC differentiation. The present data validate the utility of the K5(+)K19(-) hMEC cells for modeling key features of human MEC differentiation. This system should be useful in studying molecular/biochemical mechanisms of human MEC differentiation. BACKGROUND: Epidermal growth factor receptor (EGFR) activation plays a role in colorectal cancer (CRC) carcinogenesis, and anti-EGFR drugs are used in treatment of advanced CRC. One of the EGFR ligands is tumor-associated trypsinogen inhibitor TATI, also called serine protease inhibitor Kazal type1 (SPINK 1), which we recently showed to be an independent prognostic marker in CRC. METHODS: We studied the prognostic value of immunohistochemical expression of EGFR and concomitant expression of EGFR and TATI/SPINK1 in a series of 619 colorectal cancer patients. RESULTS: Of the samples, 92% were positive for EGFR. EGFR+/TATI+ was seen in 62.8%, EGFR+/TATI- in 29.5%, EGFR-/TATI+ in 4.9%, and EGFR-/TATI- in 2.7% of patients. EGFR expression correlated with WHO grade (p = 0.040). In univariate analysis, EGFR expression correlated with favourable survival (p = 0.006). EGFR+/TATI+ patients showed better survival than did those with other combinations (p<0.001). In multivariate analysis, EGFR+/TATI+ was an independent prognostic factor of favourable prognosis (p<0.001). CONCLUSION: Concomitant positivity of EGFR and TATI/SPINK1 predicts favourable prognosis in CRC. Pituitary adenylate cyclase-activating polypeptide (PACAP), a neuropeptide with trophic and cytoprotective effects, has been shown to affect cell survival, proliferation, and also differentiation of various cell types. The high PACAP level in the milk and its changes during lactation suggest a possible effect of PACAP on the differentiation of mammary epithelial cells. Mammary cell differentiation is regulated by hormones, growth factors, cytokines/chemokines, and angiogenic proteins. In this study, differentiation was hormonally induced by lactogenic hormones in confluent cultures of HC11 mouse mammary epithelial cells. We investigated the effect of PACAP on mammary cell differentiation as well as release of cytokines, chemokines, and growth factors. Differentiation was assessed by expression analysis of the milk protein β-casein. Differentiation significantly decreased the secretion of interferon gammainduced protein (IP)-10, "regulated upon activation normal T cell expressed and presumably secreted" (RANTES), insulin-like growth factor-binding protein (IGFBP)-3 and the epidermal growth factor receptor (EGFR) ligands, such as epidermal growth factor (EGF) and amphiregulin (AREG). The changes in the levels of IP-10 and RANTES may be relevant for the alterations in homing of T cells and B cells at different stages of mammary gland development, while the changes of the EGFR ligands may facilitate the switch from proliferative to lactating stage. PACAP did not modulate the expression of β-casein or the activity of hormone-induced pathways as determined by the analysis of phosphorylation of Akt, STAT5, and p38 MAPK. However, PACAP decreased the release of EGF and AREG from non-differentiated cells. This may influence the extracellular signal-related transactivation of EGFR in the non-differentiated mammary epithelium and is considered to have an impact on the modulation of oncogenic EGFR signaling in breast cancer.
Is the protein Papilin secreted?
Yes, papilin is a secreted protein
A sulfated glycoprotein was isolated from the culture media of Drosophila Kc cells and named papilin. Affinity purified antibodies against this protein localized it primarily to the basement membranes of embryos. The antibodies cross-reacted with another material which was not sulfated and appeared to be the core protein of papilin, which is proteoglycan-like. After reduction, papilin electrophoresed in sodium dodecyl sulfate-polyacrylamide gel electrophoresis as a broad band of about 900,000 apparent molecular weight and the core protein as a narrow band of approximately 400,000. The core protein was formed by some cell lines and by other cells on incubation with 1 mM 4-methylumbelliferyl xyloside, which inhibited formation of the proteoglycan-like form. The buoyant density of papilin in CsCl/4 M guanidine hydrochloride is 1.4 g/ml, that of the core protein is much less. Papilin forms oligomers linked by disulfide bridges, as shown by sodium dodecyl sulfate-agarose gel electrophoresis and electron microscopy. The protomer is a 225 +/- 15-nm thread which is disulfide-linked into a loop with fine, protruding thread ends. Oligomers form clover-leaf-like structures. The protein contains 22% combined serine and threonine residues and 25% combined aspartic and glutamic residues. 10 g of polypeptide has attached 6.4 g of glucosamine, 3.1 g of galactosamine, 6.1 g of uronic acid, and 2.7 g of neutral sugars. There are about 80 O-linked carbohydrate chains/core protein molecule. Sulfate is attached to these chains. The O-linkage is through an unidentified neutral sugar. Papilin is largely resistant to common glycosidases and several proteases. The degree of sulfation varies with the sulfate concentration of the incubation medium. This proteoglycan-like glycoprotein differs substantially from corresponding proteoglycans found in vertebrate basement membranes, in contrast to Drosophila basement membrane laminin and collagen IV which have been conserved evolutionarily. Two contrasting substrates, Drosophila laminin and human vitronectin, caused determined primary Drosophila embryo cells to follow alternate intermediate differentiation steps without affecting the final outcome of differentiation. Integrin alpha PS2 beta PS3 was essential for the initial spreading of myocytes on vitronectin: focal contacts rich in beta PS3 integrins formed and were connected by actin- and myosin-containing stress fibers. While alpha PS2 beta PS3 was unnecessary for myotube formation on laminin, it was required for the subsequent change to a sarcomeric cytoarchitecture. The differentiating primary cultures synthesized integrins and assembled them into detergent-insoluble, cytoskeleton-associated complexes. Collagen IV, laminin, glutactin, papilin, and other extracellular matrix proteins were made primarily by hemocytes and were secreted into the medium. Further differentiation within the cultures was influenced by secreted components and by later addition of vitronectin or bovine serum. Comparison of the differentiation of various cell types on the two substrates showed that vitronectin provided a selective advantage for the differentiation of myocytes, with enrichment over epithelia, epidermal cells, and neurites. Papilin is an extracellular matrix glycoprotein that we have found to be involved in, (1) thin matrix layers during gastrulation, (2) matrix associated with wandering, phagocytic hemocytes, (3) basement membranes and (4) space-filling matrix during Drosophila development. Determination of its cDNA sequence led to the identification of Caenorhabditis and mammalian papilins. A distinctly conserved 'papilin cassette' of domains at the amino-end of papilins is also the carboxyl-end of the ADAMTS subgroup of secreted, matrix-associated metalloproteinases; this cassette contains one thrombospondin type 1 (TSR) domain, a specific cysteine-rich domain and several partial TSR domains. In vitro, papilin non-competitively inhibits procollagen N-proteinase, an ADAMTS metalloproteinase. Inhibiting papilin synthesis in Drosophila or Caenorhabditis causes defective cell arrangements and embryonic death. Ectopic expression of papilin in Drosophila causes lethal abnormalities in muscle, Malpighian tubule and trachea formation. We suggest that papilin influences cell rearrangements and may modulate metalloproteinases during organogenesis. Papilins are extracellular matrix proteins that share a particular, common order of types of protein domains. They occur widely, from nematodes to man, and can differ in the number of repeats of a given type of domain. Protein variety is increased by differential splicing of pre-mRNA. We report that Drosophila, which has a compact genome, expresses three splice variants of papilin during embryogenesis in developmentally defined patterns. These isoforms have different numbers of Kunitz and IgC2 domains. The papilin isoforms are expressed in specific cell types and contribute to different extracellular matrices in gastrulation folds, early mesoderm, heart formation, basement membranes, and elaboration of the excorporeal peritrophic membrane that lines the gut. This finding indicates an unexpectedly broad spectrum of different pericellular matrices in Drosophila embryos. Such papilin-containing matrices have developmental as well as functional significance, as we previously showed that both suppression of papilin synthesis and ectopic overexpression lethally disrupt organogenesis. The TSR superfamily is a diverse family of extracellular matrix and transmembrane proteins, many of which have functions related to regulating matrix organization, cell-cell interactions and cell guidance. This review samples some of the contemporary literature regarding TSR superfamily members (e.g. F-spondin, UNC-5, ADAMTS, papilin, and TRAP) where specific functions are assigned to the TSR domains. Combining these observations with the published crystal structure of the TSRs of thrombospondin-1 may hold a key to the development of therapeutic agents for fighting parasitic infection and tumor growth. Papilins are homologous, secreted extracellular matrix proteins which share a common order of protein domains. They occur widely, from nematodes to man, and can differ in the number of repeats of a given type of domain. Within one species the number of repeats can vary by differential RNA splicing. A distinctly conserved cassette of domains at the amino-end of papilins is homologous with a cassette of protein domains at the carboxyl-end of the ADAMTS subgroup of secreted, matrix-associated metalloproteases. Papilins primarily occur in basement membranes. Papilins interact with several extracellular matrix components and ADAMTS enzymes. Papilins are essential for embryonic development of Drosophila melanogaster and Caenorhabditis elegans. The gonad arms of C. elegans hermaphrodites acquire invariant shapes by guided migrations of distal tip cells (DTCs), which occur in three phases that differ in the direction and basement membrane substrata used for movement. We found that mig-6 encodes long (MIG-6L) and short (MIG-6S) isoforms of the extracellular matrix protein papilin, each required for distinct aspects of DTC migration. Both MIG-6 isoforms have a predicted N-terminal papilin cassette, lagrin repeats and C-terminal Kunitz-type serine proteinase inhibitory domains. We show that mutations affecting MIG-6L specifically and cell-autonomously decrease the rate of post-embryonic DTC migration, mimicking a post-embryonic collagen IV deficit. We also show that MIG-6S has two separable functions - one in embryogenesis and one in the second phase of DTC migration. Genetic data suggest that MIG-6S functions in the same pathway as the MIG-17/ADAMTS metalloproteinase for guiding phase 2 DTC migrations, and MIG-17 is abnormally localized in mig-6 class-s mutants. Genetic data also suggest that MIG-6S and non-fibrillar network collagen IV play antagonistic roles to ensure normal phase 2 DTC guidance. OBJECTIVES: Suicidal ideation is an uncommon but worrisome symptom than can emerge during antidepressant treatment. We have described earlier the association between treatment-emergent suicidal ideation (TESI) and markers in genes encoding glutamate receptor subunits GRIK2 and GRIA3. The present genome-wide association study was conducted to identify additional genetic markers associated with TESI that may help identify individuals at high risk who may benefit from closer monitoring, alternative treatments, and/or specialty care. METHODS: A clinically representative cohort of outpatients with nonpsychotic major depressive disorder enrolled in the Sequenced Treatment Alternatives to Relieve Depression (STAR*D) trial were treated with citalopram under a standard protocol for up to 14 weeks. DNA samples from 90 White participants who developed TESI and a sex-matched and race-matched equal number of treated participants who denied any suicidal ideas were genotyped with 109 365 single nucleotide polymorphisms on the Illumina's Human-1 BeadChip. RESULTS: One marker was found to be associated with TESI in this sample at the experiment-wide adjusted P less than 0.05 level (marker rs11628713, allelic P = 6.2x10, odds ratio = 4.7, permutation P = 0.01). A second marker was associated at the experiment-wide adjusted P = 0.06 level (rs10903034, allelic P = 3.02x10, odds ratio = 2.7, permutation P = 0.06). These markers reside within the genes PAPLN and IL28RA, respectively. PAPLN encodes papilin, a protoglycan-like sulfated glycoprotein. IL28RA encodes an interleukin receptor. CONCLUSION: Together with our earlier report, these findings may shed light on the biological basis of TESI and may help identify patients at increased risk of this potentially serious adverse event. Cell invasion through basement membrane is a specialized cellular behavior critical for many developmental processes and leukocyte trafficking. Invasive cellular behavior is also inappropriately co-opted during cancer progression. Acquisition of an invasive phenotype is accompanied by changes in gene expression that are thought to coordinate the steps of invasion. The transcription factors responsible for these changes in gene expression, however, are largely unknown. C. elegans anchor cell (AC) invasion is a genetically tractable in vivo model of invasion through basement membrane. AC invasion requires the conserved transcription factor FOS-1A, but other transcription factors are thought to act in parallel to FOS-1A to control invasion. Here we identify the transcription factor HLH-2, the C. elegans ortholog of Drosophila Daughterless and vertebrate E proteins, as a regulator of AC invasion. Reduction of HLH-2 function by RNAi or with a hypomorphic allele causes defects in AC invasion. Genetic analysis indicates that HLH-2 has functions outside of the FOS-1A pathway. Using expression analysis, we identify three genes that are transcriptionally regulated by HLH-2: the protocadherin cdh-3, and two genes encoding secreted extracellular matrix proteins, mig-6/papilin and him-4/hemicentin. Further, we show that reduction of HLH-2 function causes defects in polarization of F-actin to the invasive cell membrane, a process required for the AC to generate protrusions that breach the basement membrane. This work identifies HLH-2 as a regulator of the invasive phenotype in the AC, adding to our understanding of the transcriptional networks that control cell invasion.
Are long non coding RNAs spliced?
Long non coding RNAs appear to be spliced through the same pathway as the mRNAs
Thousands of long noncoding RNAs (lncRNAs) have been found in vertebrate animals, a few of which have known biological roles. To better understand the genomics and features of lncRNAs in invertebrates, we used available RNA-seq, poly(A)-site, and ribosome-mapping data to identify lncRNAs of Caenorhabditis elegans. We found 170 long intervening ncRNAs (lincRNAs), which had single- or multiexonic structures that did not overlap protein-coding transcripts, and about sixty antisense lncRNAs (ancRNAs), which were complementary to protein-coding transcripts. Compared to protein-coding genes, the lncRNA genes tended to be expressed in a stage-dependent manner. Approximately 25% of the newly identified lincRNAs showed little signal for sequence conservation and mapped antisense to clusters of endogenous siRNAs, as would be expected if they serve as templates and targets for these siRNAs. The other 75% tended to be more conserved and included lincRNAs with intriguing expression and sequence features associating them with processes such as dauer formation, male identity, sperm formation, and interaction with sperm-specific mRNAs. Our study provides a glimpse into the lncRNA content of a nonvertebrate animal and a resource for future studies of lncRNA function. Splicing remains an incompletely understood process. Recent findings suggest that chromatin structure participates in its regulation. Here, we analyze the RNA from subcellular fractions obtained through RNA-seq in the cell line K562. We show that in the human genome, splicing occurs predomitly during transcription. We introduce the coSI measure, based on RNA-seq reads mapping to exon junctions and borders, to assess the degree of splicing completion around internal exons. We show that, as expected, splicing is almost fully completed in cytosolic polyA+ RNA. In chromatin-associated RNA (which includes the RNA that is being transcribed), for 5.6% of exons, the removal of the surrounding introns is fully completed, compared with 0.3% of exons for which no intron-removal has occurred. The remaining exons exist as a mixture of spliced and fewer unspliced molecules, with a median coSI of 0.75. Thus, most RNAs undergo splicing while being transcribed: "co-transcriptional splicing." Consistent with co-transcriptional spliceosome assembly and splicing, we have found significant enrichment of spliceosomal snRNAs in chromatin-associated RNA compared with other cellular RNA fractions and other nonspliceosomal snRNAs. CoSI scores decrease along the gene, pointing to a "first transcribed, first spliced" rule, yet more downstream exons carry other characteristics, favoring rapid, co-transcriptional intron removal. Exons with low coSI values, that is, in the process of being spliced, are enriched with chromatin marks, consistent with a role for chromatin in splicing during transcription. For alternative exons and long noncoding RNAs, splicing tends to occur later, and the latter might remain unspliced in some cases. The human genome contains many thousands of long noncoding RNAs (lncRNAs). While several studies have demonstrated compelling biological and disease roles for individual examples, analytical and experimental approaches to investigate these genes have been hampered by the lack of comprehensive lncRNA annotation. Here, we present and analyze the most complete human lncRNA annotation to date, produced by the GENCODE consortium within the framework of the ENCODE project and comprising 9277 manually annotated genes producing 14,880 transcripts. Our analyses indicate that lncRNAs are generated through pathways similar to that of protein-coding genes, with similar histone-modification profiles, splicing signals, and exon/intron lengths. In contrast to protein-coding genes, however, lncRNAs display a striking bias toward two-exon transcripts, they are predomitly localized in the chromatin and nucleus, and a fraction appear to be preferentially processed into small RNAs. They are under stronger selective pressure than neutrally evolving sequences-particularly in their promoter regions, which display levels of selection comparable to protein-coding genes. Importantly, about one-third seem to have arisen within the primate lineage. Comprehensive analysis of their expression in multiple human organs and brain regions shows that lncRNAs are generally lower expressed than protein-coding genes, and display more tissue-specific expression patterns, with a large fraction of tissue-specific lncRNAs expressed in the brain. Expression correlation analysis indicates that lncRNAs show particularly striking positive correlation with the expression of antisense coding genes. This GENCODE annotation represents a valuable resource for future studies of lncRNAs. NONCODE (http://www.bioinfo.org/noncode/) is an integrated knowledge database dedicated to non-coding RNAs (excluding tRNAs and rRNAs). Non-coding RNAs (ncRNAs) have been implied in diseases and identified to play important roles in various biological processes. Since NONCODE version 3.0 was released 2 years ago, discovery of novel ncRNAs has been promoted by high-throughput RNA sequencing (RNA-Seq). In this update of NONCODE, we expand the ncRNA data set by collection of newly identified ncRNAs from literature published in the last 2 years and integration of the latest version of RefSeq and Ensembl. Particularly, the number of long non-coding RNA (lncRNA) has increased sharply from 73 327 to 210 831. Owing to similar alternative splicing pattern to mRNAs, the concept of lncRNA genes was put forward to help systematic understanding of lncRNAs. The 56 018 and 46 475 lncRNA genes were generated from 95 135 and 67 628 lncRNAs for human and mouse, respectively. Additionally, we present expression profile of lncRNA genes by graphs based on public RNA-seq data for human and mouse, as well as predict functions of these lncRNA genes. The improvements brought to the database also include an incorporation of an ID conversion tool from RefSeq or Ensembl ID to NONCODE ID and a service of lncRNA identification. NONCODE is also accessible through http://www.noncode.org/.
Is RANKL secreted from the cells?
Receptor activator of nuclear factor κB ligand (RANKL) is a cytokine predominantly secreted by osteoblasts.
Bone destruction is a common feature of inflammatory arthritis and is mediated by osteoclasts, the only specialized cells to carry out bone resorption. Aberrant expression of receptor activator of nuclear factor kappa β ligand (RANKL), an inducer of osteoclast differentiation has been linked with bone pathology and the synovial fibroblast in rheumatoid arthritis (RA). In this manuscript, we challenge the current concept that an increase in RANKL expression governs osteoclastogenesis and bone destruction in autoimmune arthritis. We isolated human fibroblasts from RA, pyrophosphate arthropathy (PPA) and osteoarthritis (OA) patients and analyzed their RANKL/OPG expression profile and the capacity of their secreted factors to induce osteoclastogenesis. We determined a 10-fold increase of RANKL mRNA and protein in fibroblasts isolated from RA relative to PPA and OA patients. Peripheral blood mononuclear cells (PBMC) from healthy volunteers were cultured in the presence of RA, PPA and OA synovial fibroblast conditioned medium. Osteoclast differentiation was assessed by expression of tartrate-resistant acid phosphatase (TRAP), vitronectin receptor (VNR), F-actin ring formation and bone resorption assays. The formation of TRAP(+), VNR(+) multinucleated cells, capable of F-actin ring formation and lacunar resorption in synovial fibroblast conditioned medium cultures occured in the presence of osteoprotegerin (OPG) a RANKL antagonist. Osteoclasts did not form in these cultures in the absence of macrophage colony stimulating factor (M-CSF). Our data suggest that the conditioned medium of pure synovial fibroblast cultures contain inflammatory mediators that can induce osteoclast formation in human PBMC independently of RANKL. Moreover inhibition of the TNF or IL-6 pathway was not sufficient to abolish osteoclastogenic signals derived from arthritic synovial fibroblasts. Collectively, our data clearly show that alternate osteoclastogenic pathways exist in inflammatory arthritis and place the synovial fibroblast as a key regulatory cell in bone and joint destruction, which is a hallmark of autoimmune arthritis. Pulsed electromagnetic field (PEMF) has been shown to increase bone mineral density in osteoporosis patients and prevent bone loss in ovariectomized rats. But the mechanisms through which PEMF elicits these favorable biological responses are still not fully understood. Receptor activator of nuclear factor κB ligand (RANKL) and osteoprotegerin (OPG) are cytokines predomitly secreted by osteoblasts and play a central role in differentiation and functional activation of osteoclasts. The purpose of this study was to investigate the effects of PEMF on RANKL and OPG expression in ovariectomized rats. Thirty 3-month-old female Sprague-Dawley rats were randomly divided into three groups: sham-operated control (Sham), ovariectomy control (OVX), and ovariectomy with PEMF treatment (PEMF). After 12-week interventions, the results showed that PEMF increased serum 17β-estradiol level, reduced serum tartrate-resistant acid phosphatase level, increased bone mineral density, and inhibited deterioration of bone microarchitecture and strength in OVX rats. Furthermore, PEMF could suppress RANKL expression and improve OPG expression in bone marrow cells of OVX rats. In conclusion, this study suggests that PEMF can prevent ovariectomy-induced bone loss through regulating the expression of RANKL and OPG. Zebrafish scales consist of bone-forming osteoblasts, bone-resorbing osteoclasts, and calcified bone matrix. To elucidate the underlying molecular mechanism of the effects induced by dynamic and static acceleration, we investigated the scale osteoblast- and osteoclast-specific marker gene expression involving osteoblast-osteoclast communication molecules. Osteoblasts express RANKL, which binds to the osteoclast surface receptor, RANK, and stimulates bone resorption. OPG, on the other hand, is secreted by osteoblast as a decoy receptor for RANKL, prevents RANKL from binding to RANK and thus prevents bone resorption. Therefore, the RANK-RANKL-OPG pathway contributes to the regulation of osteoclastogenesis by osteoblasts. Semaphorin 4D, in contrast, is expressed on osteoclasts, and binding to its receptor Plexin-B1 on osteoblasts results in suppression of bone formation. In the present study, we found that both dynamic and static acceleration at 3.0×g decreased RANKL/OPG ratio and increased osteoblast-specific functional mRNA such as alkaline phosphatase, while static acceleration increased and dynamic acceleration decreased osteoclast-specific mRNA such as cathepsin K. Static acceleration increased semaphorin 4D mRNA expression, while dynamic acceleration had no effect. The results of the present study indicated that osteoclasts have predomit control over bone metabolism via semaphorin 4D expression induced by static acceleration at 3.0×g. Osteoprotegerin (OPG) is a secreted glycoprotein and a member of the tumor necrosis factor receptor superfamily. It usually functions in bone remodeling, by inhibiting osteoclastogenesis through interaction with a receptor activator of the nuclear factor κB (RANKL). Transglutaminases-2 (Tgase-2) is a group of multifunctional enzymes that plays a role in cancer cell metastasis and bone formation. However, relationship between OPG and Tgase-2 is not studied. Therefore, we investigated the involvement of 12-O-Tetradecanoylphorbol 13-acetate in the expression of OPG in MG-63 osteosarcoma cells. Interleukin-1β time-dependently induced OPG and Tgase-2 expression in cell lysates and media of the MG-63 cells by a Western blot. Additional 110 kda band was found in the media of MG-63 cells. 12-O-Tetradecanoylphorbol 13-acetate also induced OPG and Tgase-2 expression. However, an 110 kda band was not found in TPA-treated media of MG-63 cells. Cystamine, a Tgase-2 inhibitor, dose-dependently suppressed the expression of OPG in MG-63 cells. Gene silencing of Tgase-2 also signifi cantly suppressed the expression of OPG in MG-63 cells. Next, we examined whether a band of 110 kda of OPG contains an isopeptide bond, an indication of Tgase-2 action, by monoclonal antibody specifi c for the isopeptide bond. However, we could not fi nd the isopeptide bond at 110 kda but 77 kda, which is believed to be the band position of Tgase-2. This suggested that 110 kda is not the direct product of Tgase-2's action. All together, OPG and Tgase-2 is induced by IL-1β or TPA in MG-63 cells and Tgase-2 is involved in OPG expression in MG-63 cells. BACKGROUND: Resistance to apoptosis is a major problem in ovarian cancer (OC) and correlates with poor prognosis. Osteoprotegerin (OPG) is a soluble secreted factor that acts as a decoy receptor for receptor activator of NF-κB ligand (RANKL) and tumor necrosis factor-related apoptosis-inducing ligand (TRAIL). OPG has been reported to attenuate TRAIL-induced apoptosis in a variety of cancer cells, including OC cells. OPG-mediated protection against TRAIL has been attributed to its decoy receptor function. However, OPG activates integrin/focal adhesion kinase (FAK) signaling in endothelial cells. In OC cells, activation of integrin/FAK signaling inhibits TRAIL-induced apoptosis. Based on these observations, we hypothesized that OPG could attenuate TRAIL-induced apoptosis in OC cells through integrin/FAK signaling. METHODS: In vitro experiments including immunoblots, colony formation assays, and apoptosis measurements were used to assess the effect of OPG on TRAIL-induced apoptosis. RESULTS: Exogenous OPG protected from TRAIL-induced apoptosis in a TRAIL binding-independent manner and OPG protection was αvβ3 and αvβ5 integrin/FAK signaling-dependent. Moreover, OPG-mediated activation of integrin/FAK signaling resulted in the activation of Akt. Inhibition of both integrin/FAK and Akt signaling significantly inhibited OPG-mediated attenuation of TRAIL-induced apoptosis. Although OPG also stimulated ERK1/2 phosphorylation, inhibition of ERK1/2 signaling did not significantly altered OPG protection. CONCLUSIONS: Our studies provide evidence, for the first time, that OPG can attenuate TRAIL-induced apoptosis in a TRAIL binding-independent manner through the activation of integrin/FAK/Akt signaling in OC cells.
Does metformin interfere thyroxine absorption?
No. There are not reported data indicating that metformin reduce with thyroxine absorption.
Which miRNAs could be used as potential biomarkers for epithelial ovarian cancer?
miR-200a, miR-100, miR-141, miR-200b, miR-200c, miR-203, miR-510, miR-509-5p, miR-132, miR-26a, let-7b, miR-145, miR-182, miR-152, miR-148a, let-7a, let-7i, miR-21, miR-92 and miR-93 could be used as potential biomarkers for epithelial ovarian cancer.
OBJECTIVE: To determine the utility of serum miRNAs as biomarkers for epithelial ovarian cancer. METHODS: Twenty-eight patients with histologically confirmed epithelial ovarian cancer were identified from a tissue and serum bank. Serum was collected prior to definitive therapy. Fifteen unmatched, healthy controls were used for comparison. Serum was obtained from all patients. RNA was extracted using a derivation of the single step Trizol method. The RNA from 9 cancer specimens was compared to 4 normal specimens with real-time PCR using the TaqMan Array Human MicroRNA panel. Twenty-one miRNAs were differentially expressed between normal and patient serum. Real-time PCR for the 21 individual miRNAs was performed on the remaining 19 cancer specimens and 11 normal specimens. RESULTS: Eight miRNAs of the original twenty-one were identified that were significantly differentially expressed between cancer and normal specimens using the comparative C(t) method. MiRNAs-21, 92, 93, 126 and 29a were significantly over-expressed in the serum from cancer patients compared to controls (p<.01). MiRNAs-155, 127 and 99b were significantly under-expressed (p<.01). Additionally, miRs-21, 92 and 93 were over-expressed in 3 patients with normal pre-operative CA-125. CONCLUSION: We demonstrate that the extraction of RNA and subsequent identification of miRNAs from the serum of individuals diagnosed with ovarian cancer is feasible. Real-time PCR-based microarray is a novel and practical means to performing high-throughput investigation of serum RNA samples. miRNAs-21, 92 and 93 are known oncogenes with therapeutic and biomarker potential. MicroRNAs (miRNA) are approximately 22-nucleotide noncoding RNAs that negatively regulate protein-coding gene expression in a sequence-specific manner via translational inhibition or mRNA degradation. Our recent studies showed that miRNAs exhibit genomic alterations at a high frequency and their expression is remarkably deregulated in ovarian cancer, strongly suggesting that miRNAs are involved in the initiation and progression of this disease. In the present study, we performed miRNA microarray to identify the miRNAs associated with chemotherapy response in ovarian cancer and found that let-7i expression was significantly reduced in chemotherapy-resistant patients (n = 69, P = 0.003). This result was further validated by stem-loop real-time reverse transcription-PCR (n = 62, P = 0.015). Both loss-of-function (by synthetic let-7i inhibitor) and gain-of-function (by retroviral overexpression of let-7i) studies showed that reduced let-7i expression significantly increased the resistance of ovarian and breast cancer cells to the chemotherapy drug, cis-platinum. Finally, using miRNA microarray, we found that decreased let-7i expression was significantly associated with the shorter progression-free survival of patients with late-stage ovarian cancer (n = 72, P = 0.042). This finding was further validated in the same sample set by stem-loop real-time reverse transcription-PCR (n = 62, P = 0.001) and in an independent sample set by in situ hybridization (n = 53, P = 0.049). Taken together, our results strongly suggest that let-7i might be used as a therapeutic target to modulate platinum-based chemotherapy and as a biomarker to predict chemotherapy response and survival in patients with ovarian cancer. OBJECTIVES: Let-7 is a family of small non-coding RNAs regulating the expression of many genes that control important cellular activities. Let-7 is shown in vitro to sensitize cancer cells to platinum, but induce ovarian cancer resistance to paclitaxel. This study aims to investigate the effect of let-7a expression on survival outcomes of epithelial ovarian cancer (EOC) patients treated with different chemotherapy. METHODS: Let-7a expression was measured with qRT-PCR in ovarian tumors of 178 EOC patients who received platinum-based chemotherapy with and without paclitaxel after surgery. Survival analysis was performed to assess the effects of let-7a and chemotherapy on disease outcomes. RESULTS: Let-7a expression was detectable in the EOC samples, but the expression was not associated with disease stage, tumor grade, histology and debulking results. Patients who responded to platinum with paclitaxel had significantly lower let-7a than those who did not. Survival analyses showed that patients with high let-7a had better survival compared to those with low let-7a when they were treated with platinum without paclitaxel. The hazards ratios (HRs) for death and disease progression were 0.52 (95% CI: 0.29-0.96) and 0.48 (0.26-0.89) for high let-7a when compared to low let-7a, respectively. However, when patients were treated with platinum and paclitaxel, high let-7a was associated with worse progression-free and overall survival. The HRs for death and disease progression were 3.87 (95% CI: 1.28-11.66) and 3.48 (95% CI: 1.25-9.67) for high let-7a when compared to low let-7a, respectively. Further studies showed that among patients with low let-7a, those treated with paclitaxel in addition to platinum survived better than those treated without paclitaxel [adjusted-HRs were 0.31 (95% CI: 0.15-0.66) for death and 0.40 (95% CI: 0.22-0.75) for disease], while among those with high let-7a, the two types of treatment made no difference in patient survival. CONCLUSIONS: The study suggests that the beneficial impact of the addition of paclitaxel on EOC survival was significantly linked to let-7a levels, and that miRNAs such as let-7a may be a useful marker for selection of chemotherapeutic agents in EOC management. microRNAs (miRs) are endogenous small non-coding RNAs that are aberrantly expressed in various carcinomas. miR-152 and miR-148a have not been comprehensively investigated in ovarian cancer. Thus, the aim of this study was to identify the role of miR-152 and miR-148a in epithelial ovarian cancer. Total RNA was extracted from tissues of 78 patients with epithelial ovarian cancer, 17 normal ovarian epithelium tissues and two ovarian cancer cell lines. Using quantitative real-time PCR (qRT-PCR) followed by the 2-ΔΔCT method for calculating the results, we found that the expression levels of miR-152 were significantly decreased in ovarian cancer tissues compared to normal ovarian epithelium tissues (p<0.05). However, although the expression of miR-148a was also decreased in 65% of patients, no statistically significant difference in expression was found. A strong correlation was found between the expression of miR-152 and miR-148a (p<0.001, Pearson's correlation). The relationship between miR-152 or miR-148a expression levels in ovarian cancer and clinicopathological features, response to therapy and short-term survival was analyzed and the results showed that no correlation existed. In addition, we found that both miR-152 and miR-148a were down-regulated in ovarian cancer cell lines. After miR-152 or miR-148a mimics were transfected into ovarian cancer cell lines, the MTT cell proliferation assay showed that cell proliferation was significantly inhibited. Taken together, miR-152 and miR-148a may be involved in the carcinogenesis of ovarian cancer through deregulation of cell proliferation. They may be novel biomarkers for early detection or therapeutic targets of ovarian cancer. BACKGROUND: There is a critical need for improved diagnostic markers for high grade serous epithelial ovarian cancer (SEOC). MicroRNAs are stable in the circulation and may have utility as biomarkers of maligcy. We investigated whether levels of serum microRNA could discriminate women with high-grade SEOC from age matched healthy volunteers. METHODS: To identify microRNA of interest, microRNA expression profiling was performed on 4 SEOC cell lines and normal human ovarian surface epithelial cells. Total RNA was extracted from 500 μL aliquots of serum collected from patients with SEOC (n = 28) and age-matched healthy donors (n = 28). Serum microRNA levels were assessed by quantitative RT-PCR following preamplification. RESULTS: microRNA (miR)-182, miR-200a, miR-200b and miR-200c were highly overexpressed in the SEOC cell lines relative to normal human ovarian surface epithelial cells and were assessed in RNA extracted from serum as candidate biomarkers. miR-103, miR-92a and miR -638 had relatively invariant expression across all ovarian cell lines, and with small-nucleolar C/D box 48 (RNU48) were assessed in RNA extracted from serum as candidate endogenous normalizers. No correlation between serum levels and age were observed (age range 30-79 years) for any of these microRNA or RNU48. Individually, miR-200a, miR-200b and miR-200c normalized to serum volume and miR-103 were significantly higher in serum of the SEOC cohort (P < 0.05; 0.05; 0.0005 respectively) and in combination, miR-200b + miR-200c normalized to serum volume and miR-103 was the best predictive classifier of SEOC (ROC-AUC = 0.784). This predictive model (miR-200b + miR-200c) was further confirmed by leave one out cross validation (AUC = 0.784). CONCLUSIONS: We identified serum microRNAs able to discriminate patients with high grade SEOC from age-matched healthy controls. The addition of these microRNAs to current testing regimes may improve diagnosis for women with SEOC. OBJECTIVE: MicroRNA (miRNA) is an abundant class of small noncoding RNAs that act as gene regulators. Recent studies have suggested that miRNA deregulation is associated with the initiation and progression of human cancer. However, information about cancer-related miRNA is mostly limited to tissue miRNA. The aim of this study was to find specific profiles of serum-derived miRNAs of ovarian cancer based on a comparative study using a miRNA microarray of serum, tissue, and ascites. METHODS: From 2 ovarian cancer patients and a healthy control, total RNA was isolated from their serum, tissue, and ascites, respectively, and analyzed by a microarray. Under the comparative study of each miRNA microarray, we sorted out several miRNAs showing a consistent regulation tendency throughout all 3 specimens and the greatest range of alteration in serum as potential biomarkers. The availability of biomarkers was confirmed by qRT-PCR of 18 patients and 12 controls. RESULTS: Out of 2222 kinds of total miRNAs that were identified in the microarray analysis, 95 miRNAs were down-regulated and 88 miRNAs were up-regulated, in the serum, tissue, and ascites of cancer patients. Among the miRNAs that showed a consistent regulation tendency through all specimens and showed more than a 2-fold difference in serum, 5 miRNAs (miR-132, miR-26a, let-7b, miR-145, and miR-143) were determined as the 5 most markedly down-regulated miRNAs in the serum from ovarian cancer patients with respect to those of controls. Four miRNAs (miR-132, miR-26a, let-7b, and miR-145) out of 5 selected miRNAs were significantly underexpressed in the serum of ovarian cancer patients in qRT-PCR. CONCLUSIONS: Serum miR-132, miR-26a, let-7b, and miR-145 could be considered as potential candidates as novel biomarkers in serous ovarian cancer. Also, serum miRNAs is a promising and useful tool for discriminating between controls and patients with serous ovarian cancer. Recent investigations have confirmed up-regulation of serum miR-21 and its diagnostic and prognostic value in several human maligcies. In this study, we examined serum miR-21 levels in epithelial ovarian cancer (EOC) patients, and explored its association with clinicopathological factors and prognosis. The results showed significantly higher serum miR-21 levels in EOC patients than in healthy controls. In addition, increased serum miR-21 expression was correlated with advanced FIGO stage, high tumor grade, and shortened overall survival. These findings indicate that serum miR-21 may serve as a novel diagnostic and prognostic marker, and be used as a therapeutic target for the treatment of EOC. Epithelial ovarian cancer (EOC) is the leading cause of death among gynecologic maligcies. Despite great efforts to improve early detection and optimize chemotherapeutic regimens, the 5-year survival rate is only 30% for patients presenting with late-stage ovarian cancer. The high mortality of this disease is due to late diagnosis in over 70% of ovarian cancer cases. A class of small noncoding RNAs, or microRNAs, was found to regulate gene expression at the post-transcriptional level. Some, but not all, of the data indicated that the miR-200 family was dysregulated in a variety of maligcies. In this study, we demonstrated that miR-200a and E-cadherin were significantly upregulated in EOC compared to benign epithelial ovarian cysts and normal ovarian tissues. However, further stratification of the subject indicated that the expression levels of miR-200a were significantly downregulated in late-stage (FIGO III+V) and grade 3 groups compared with early stage (FIGO I+II) and grade 1 to 2 groups. Similarly, relatively low levels of miR-200a were observed in the lymph compared to the node-negative group. E-cadherin expression was found to be absent in normal ovarian tissue and was frequently expressed in benign epithelial ovarian cysts, with absence or low levels observed in late-stage ovarian cancers. There was a significantly positive correlation between miR-200a and E-cadherin in EOC. The biphasic expression pattern suggested that miR-200a levels may serve as novel biomarkers for the early detection of EOC, and miR-200a and E-cadherin are candidate targets for the development of new treatment modalities against ovarian cancer. MicroRNA-203 (miR-203), possessing tumor suppressive or promotive activities, has been found to be downregulated or upregulated in different cancer types. The purpose of this study was to investigate whether the increased expression of miR-203 can be used as a noninvasive diagnostic and prognostic biomarker in epithelial ovarian cancer (EOC). Real-time quantitative PCR was performed to detect the expression levels of miR-203 in EOC tissues. The expression levels of miR-203 were significantly higher in EOC tissues compared to adjacent non-cancerous tissues (p < 0.001). High expression of miR-203 was observed in 65.38 % (102/156) of EOC. In addition, high miR-203 expression was found to be closely correlated with advanced FIGO stage (p < 0.001), higher histological grade (p = 0.02), lymph node involvement (p < 0.001), and positive recurrence (p < 0.001). Moreover, high miR-203 expression was correlated with shorter overall survival (p < 0.001) and shorter progression-free survival (p < 0.001) of EOC patients. Furthermore, multivariate analysis showed that the status of miR-203 expression was an independent predictor for both overall survival and progression-free survival in EOC. These findings provide the convincing evidence for the first time that the upregulation of miR-203 may serve as a novel molecular marker to predict the aggressive tumor progression and unfavorable prognosis of EOC patients.
Which acetylcholinesterase inhibitors are used for treatment of myasthenia gravis?
Pyridostigmine and neostygmine are acetylcholinesterase inhibitors that are used as first-line therapy for symptomatic treatment of myasthenia gravis. Pyridostigmine is the most widely used acetylcholinesterase inhibitor. Extended release pyridotsygmine and novel acetylcholinesterase inhibitors inhibitors with oral antisense oligonucleotides are being studied.
Treatment for myasthenia gravis should be individualized to each patient based on the clinical characteristics of myasthenia including the distribution, duration, and severity of weakness and resulting functional impairment; the risks for treatment complications related to age, gender, and medical comorbidities; and the presence of thymoma. Acetylcholinesterase inhibitors provide temporary, symptomatic treatment for all forms of myasthenia gravis. Immune modulators address the underlying autoimmune process in myasthenia gravis, but are associated with potential complications and side effects. Most patients with generalized myasthenia who have significant weakness beyond the ocular muscles and who remain symptomatic, despite treatment with cholinesterase inhibitors, are candidates for immune modulation. Although corticosteroids are effective for long-term immune modulation in myasthenia gravis, several more contemporary immunomodulators including azathioprine, cyclosporine, and mycophenolate mofetil have shown efficacy in myasthenia gravis and are used increasingly as first-line treatments and as steroid-sparing agents. Plasma exchange is used to achieve rapid improvement in patients with myasthenic crisis or exacerbation, to improve strength before a surgical procedure or thymectomy, and to minimize steroid-induced exacerbation in patients with oropharyngeal or respiratory muscle weakness. Intravenous immunoglobulin represents an alternative to plasma exchange in patients requiring relatively rapid short-term improvement in the setting of poor venous access. Because of a lack of controlled trials, the role of thymectomy in nonthymomatous myasthenia gravis is unclear, although evidence suggests that thymectomy increases the probability for myasthenic remission or improvement. INTRODUCTION: For more than 50 years the acetylcholinesterase inhibitor pyridostigmine bromide has been the drug of choice in the symptomatic therapy for myasthenia gravis. The sustained-release dosage form of pyridostigmine (SR-Pyr) is only available in a limited number of countries (e.g. in the United States and Germany). Astonishingly, the therapeutic usefulness of SR-Pyr has not yet been evaluated. METHODS: In this non-interventional prospective open-label trial, 72 patients with stable myasthenia gravis were switched from instant-release dosage forms of pyridostigmine bromide to SR-Pyr. The results from the 37 patients younger than 60 years were separately analyzed. RESULTS: The initial daily dose of SR-Pyr was 288.1 ± 171.0mg. The drug switch was unproblematic in all patients. The number of daily doses was significantly reduced from 4.3 to 3.6 (p=0.011). The switch to SR-Pyr ameliorated the total quantified myasthenia gravis (QMG) score from 0.9 ± 0.5 to 0.6 ± 0.4 (p<0.001) in all patients and in the younger subgroup. This was accompanied by a significant improvement in the quality of life parameters. The health status valued by EuroQoL questionnaire improved from 0.626 ± 0.286 to 0.782 ± 0.186 (p<0.001). After switching to SR-Pyr, 28 adverse reactions disappeared and 24 adverse reactions occurred less frequent or weaker, however, 17 new adverse reactions were documented. CONCLUSIONS: Our results support the usefulness of SR-Pyr in an individualized therapeutic regimen to improve quality of life regardless of the patient's age in myasthenia gravis. Myasthenia gravis (MG) is caused by failure of chemical transmission at the neuromuscular junction. It is an autoimmune disorder in which antibodies interfere with neuromuscular transmission. It has a prevalence of around 20 per 100,000. The incidence is bimodal with a 2:1 female to male ratio in the younger population and a reversed sex ratio over the age of 60. Around 15% of cases are associated with a thymoma. MG presents with fatiguable painless muscle weakness. Diplopia and ptosis are the most common presenting features. Around 80% of patients presenting with ocular MG will subsequently develop more generalised weakness. Respiratory muscle weakness is the most serious manifestation of MG and can be fatal. A detailed history is the most valuable tool in the diagnosis of MG. This should elicit the pattern of weakness, severity and diurnal variation. Exacerbating factors including extremes of weather, emotional stress, menstruation and intercurrent illness should be enquired about. No one diagnostic test is 100% sensitive and patients who have negative antibodies and normal neurophysiology may still have MG. Treatment should be directed at ameliorating weakness with acetylcholinesterase blockers and modulating the immune system. Pyridostigmine is the most widely used acetylcholinesterase inhibitor. Most patients with generalised MG require immunomodulatory therapy and prednisolone is generally used as the first-line agent. Despite the availability of symptomatic and immunomodulatory treatment, up to 20% of patients will experience a myasthenic crisis requiring admission for ventilatory support at some stage. Acquired myasthenia gravis (MG) is a chronic autoimmune disorder of the neuromuscular junction, characterized clinically by muscle weakness and abnormal fatigability on exertion. Current guidelines and recommendations for MG treatment are based largely on clinical experience, retrospective analyses and expert consensus. Available therapies include oral acetylcholinesterase (AChE) inhibitors for symptomatic treatment, and short- and long-term disease-modifying treatments. This review focuses on treatment of MG, mainly on the use of the AChE inhibitor pyridostigmine. Despite a lack of data from well controlled clinical trials to support their use, AChE inhibitors, of which pyridostigmine is the most commonly used, are recommended as first-line therapy for MG. Pyridostigmine has been used as a treatment for MG for over 50 years and is generally considered safe. It is suitable as a long-term treatment in patients with generalized non-progressive milder disease, and as an adjunctive therapy in patients with severe disease who are also receiving immunotherapy. Novel AChE inhibitors with oral antisense oligonucleotides have been developed and preliminary results appear to be promising. In general, however, AChE inhibitors provide only partial benefit and most patients eventually switch to long-term immunosuppressive therapies, most frequently corticosteroids and/or azathioprine. Although AChE inhibitors are known to be well tolerated and effective in relieving the symptoms of MG, further efforts are required to improve treatment options for the management of this disorder. Myasthenia gravis is an autoimmune neuromuscular disorder. There are several treatment options, including symptomatic treatment (acetylcholinesterase inhibitors), short-term immunosuppression (corticosteroids), long-term immunosuppression (azathioprine, cyclosporine, cyclophosphamide, methotrexate, mycophenolate mofetil, rituximab, tacrolimus), rapid acting short-term immunomodulation (intravenous immunoglobulin, plasma exchange), and long-term immunomodulation (thymectomy). This review explores in detail these different treatment options. Potential future treatments are also discussed.
Has Denosumab (Prolia) been approved by FDA?
Yes, Denosumab was approved by the FDA in 2010.
Osteoporosis in men is finally receiving some attention; it has been realized that men are more likely to die after hip fracture. Methods for screening men for osteoporosis include dual energy x-ray absorptiometry and use of fracture risk calculators such as FRAX (World Health Organization) and the Garvan nomogram. Evaluation of men will often identify secondary causes of osteoporosis as well as multiple risk factors. Alendronate, risedronate, zoledronic acid, and teriparatide are US Food and Drug Administration (FDA)--approved therapy for men. Men on androgen deprivation therapy (ADT) are at high risk for bone loss and fracture, and all the bisphosphonates have been shown to increase bone density. The new antiresorptive drug, denosumab, although FDA-approved only for postmenopausal women, has been shown in a study of men on ADT to increase bone density in spine, hip, and forearm and decrease vertebral fractures on x-ray. Thus, there is great progress in osteoporosis in men, and recognition of its importance is increasing. Osteoporosis is a common consequence of androgen deprivation therapy (ADT) for prostate cancer. Up to 20% of men on ADT for localized prostate cancer will fracture within 5 years. Fortunately, generally safe and effect therapy is available. Although once considered non-controversial, there is some concern about calcium supplementation, but all studies of osteoporosis therapy in men have included calcium. In most older men, serum 25-hydroxyvitamin D levels are likely to be low, although again there is controversy about the ideal level. Many experts believe that all older men, including those on ADT, need to have a level of >30 ng/ml, which is easily accomplished. Bone mineral density (BMD) testing by dual energy X-ray absorptiometry (DXA) is indicated for men on ADT. Interestingly, forearm DXA may be particularly important in ADT men, in addition to spine and hip. Some experts have suggested that men on ADT with a T-score of ≤-1.5 should be treated. Alternatively FRAX or another risk calculator can be used. Oral and intravenous bisphosphonates are FDA approved treatments for men with osteoporosis and increase BMD in men on ADT. Potential off-label agents include raloxifene and toremifene. The latter and denosumab have been shown to increase bone density and decrease vertebral fractures in men on ADT. Raloxifene and denosumab are only FDA approved for postmenopausal osteoporosis. Thus, prevention of fractures can be accomplished in this high risk population. The Austrian Society for Bone and Mineral Research routinely publishes evidence-based guidelines for the treatment of postmenopausal osteoporosis. The fully human monoclonal antibody denosumab (Prolia(®)) has been recently approved by the European Medical Agency (EMEA) and the Food and Drug Administration (FDA) for the treatment of postmenopausal osteoporosis. Denosumab has been shown to reduce vertebral, non-vertebral,and hip-fracture risk effectively. Together with alendronate, risedronate, zoledronate, ibandronate, strontium ranelate, and raloxifene, denosumab constitutes an effective option in the treatment of postmenopausal osteoporosis. Therapeutic antibodies have captured substantial attention due to the relatively high rate at which these products reach marketing approval, and the subsequent commercial success they frequently achieve. In the 2000s, a total of 20 antibodies (18 full-length IgG and 2 Fab) were approved by the Food and Drug Administration (FDA) or European Medicines Agency (EMA). In the 2010s to date, an additional 3 antibodies (denosumab, belimumab, ipilimumab) have been approved and one antibody-drug conjugate (brentuximab vedotin) is undergoing regulatory review and may be approved in the US by August 30, 2011. However, a less heralded group of antibody-based therapeutics comprising proteins or peptides fused with an Fc is following the success of classical antibodies. BACKGROUND: Bone metastases are common in patients with hormone-refractory prostate cancer. In a study of autopsies of patients with prostate cancer, 65%-75% had bone metastases. Bone metastases place a substantial economic burden on payers with estimated total annual costs of $1.9 billion in the United States. Skeletal-related events (SREs), including pathologic fractures, spinal cord compression, surgery to bone, and radiation to bone, affect approximately 50% of patients with bone metastases. They are associated with a decreased quality of life and increased health care costs. Zoledronic acid is an effective treatment in preventing SREs in solid tumors and multiple myeloma. Recently, denosumab was FDA-approved for prevention of SREs in patients with bone metastases from solid tumors. A Phase 3 clinical trial (NCT00321620) demonstrated that denosumab had superior efficacy in delaying first and subsequent SREs compared with zoledronic acid. However, the economic value of denosumab has not been assessed in patients with hormone-refractory prostate cancer. OBJECTIVE: To compare the cost-effectiveness of denosumab with zoledronic acid in the treatment of bone metastases in men with hormone-refractory prostate cancer. METHODS: An Excel-based Markov model was developed to assess costs and effectiveness associated with the 2 treatments over a 1- and 3-year time horizon. Because the evaluation was conducted from the perspective of a U.S. third-party payer, only direct costs were included. Consistent with the primary outcome in the Phase 3 trial, effectiveness was assessed based on the number of SREs. The model consisted of 9 health states defined by SRE occurrence, SRE history, disease progression, and death. A hypothetical cohort of patients with hormone-refractory prostate cancer received either denosumab 120 mg or zoledronic acid 4 mg at the model entry and transitioned among the 9 health states at the beginning of each 13-week cycle. Transition probabilities associated with experiencing the first SRE, subsequent SREs, disease progression, and death were primarily derived from the results of the Phase 3 clinical trial and were supplemented with published literature. The model assumed that a maximum of 1 SRE could occur in each cycle. Drug costs included wholesale acquisition cost, health care professional costs associated with drug administration, and drug monitoring costs, if applicable. Nondrug costs included incremental costs associated with disease progression, costs associated with SREs, and terminal care costs, which were derived from the literature. Adverse event (AE) costs were estimated based on the incidence rates reported in the Phase 3 trial. Resource utilization associated with AEs was estimated based on consultation with a senior medical director employed by the study sponsor. All costs were presented in 2010 dollars. The base case estimated the incremental total cost per SRE avoided over a 1-year time horizon. Results for a 3-year time horizon were also estimated. One-way sensitivity analyses and probabilistic sensitivity analyses (PSA) were performed to test the robustness of the model. RESULTS: In the base case, the total per patient costs incurred over 1 year were estimated at $35,341 ($19,230 drug costs and $16,111 nondrug costs) for denosumab and $27,528 ($10,960 drug costs and $16,569 nondrug costs) for zoledronic acid, with an incremental total direct cost of $7,813 for denosumab. The estimated numbers of SREs per patient during the 1-year period were 0.49 for denosumab and 0.60 for zoledronic acid, resulting in an incremental number of SREs of -0.11 in the denosumab arm. The estimated incremental total direct costs per SRE avoided with the use of denosumab instead of zoledronic acid were $71,027 for 1 year and $51,319 for 3 years. The 1-way sensitivity analysis indicated that the results were sensitive to the drug costs, median time to first SRE, and increased risk of SRE associated with disease progression. Results of the PSA showed that based on willingness-to-pay thresholds of $70,000, $50,000, and $30,000 per SRE avoided, respectively, denosumab was cost-effective compared with zoledronic acid in 49.5%, 17.5%, and 0.3% of the cases at 1 year, respectively, and 79.0%, 49.8%, and 4.1% of the cases at 3 years, respectively. CONCLUSIONS: Although denosumab has demonstrated benefits over zoledronic acid in preventing or delaying SREs in a Phase 3 trial, it may be a costly alternative to zoledronic acid from a U.S. payer perspective. Most men with recurrent prostate cancer (CaP) initially respond to androgen deprivation therapy but eventually develop metastatic castration-resistant prostate cancer (CRPC). Over the last decade, new therapeutic targets have been identified in CRPC and several new drugs have reached advanced stages of clinical development. In 2010, the Food and Drug Administration (FDA) approved sipuleucel-T and cabazitaxel, and in 2011, abiraterone for patients with metastatic CRPC based on phase 3 trials showing improved survival. Although not yet available for clinical use, a press release in June 2011 announced that radium 223 also demonstrated a survival advantage in men with metastatic CRPC. Emerging therapies in advanced stages of clinical development in CRPC include the hormonal therapies MDV3100 and TAK 700, and the immunotherapy ipilimumab. Results are also pending on phase 3 studies comparing docetaxel plus prednisone with docetaxel given with the novel agents aflibercept, dasatinib, lenalidomide, and custirsen. In addition to these new and emerging therapeutic agents, denosumab was approved for the prevention of skeletal complications in patients with bone metastases due to solid tumor maligcies, providing an alternative to zoledronic acid. While the addition of these new treatment options is a great advance for men with metastatic CRPC, there are many new questions arising regarding sequencing of these treatments with each other, with previously existing therapies, and with the emerging agents now in clinical trials. Furthermore, there are concerns that on-going phase 3 trials may be contaminated if patients go off study treatment to start 1 of the newly approved agents or take the agent subsequently. These realities make clinical trial design more challenging than ever. BACKGROUND: In 2007, the Agency for Healthcare Research and Quality(AHRQ) published a systematic review on the comparative effectiveness of treatments for osteoporosis. The review included studies on the benefits and risks of medications and therapies used to prevent fractures in postmenopausal women and men with low bone density (osteopenia) or osteoporosis. Factors that may affect adherence to treatment, and monitoring for the identification of those most likely to benefit from treatment were also included in this review. AHRQ published an updated review in March 2012 that summarized the benefits and risks of osteoporosis medications in treatment and prevention of osteoporosis, including bisphosphonates (aledronate, risedronate, ibandronate, zoledronic acid), parathyroid hormone, teriparatide, calcitonin, estrogens (for prevention in postmenopausal women), selective estrogen receptor modulators (raloxifene), and denosumab(approved by the FDA in 2010). In addition, dietary and supplemental calcium and vitamin D, as well as weight-bearing exercise, for the preservation of bone mass and the decrease of fracture risk in patients with osteoporosis, were evaluated. OBJECTIVES: To (a) familiarize health care professionals with the methods and findings from AHRQ's 2012 comparative effectiveness review on treatments to prevent fractures in men and women with low bone density or osteoporosis, (b) encourage consideration and application of the findings of this review in clinical and managed care settings, and (c) identify limitations and gaps in the existing research with respect to the benefits and risks of treatments for osteoporosis. SUMMARY: Osteoporosis is a prevalent systemic skeletal disease caused by bone deterioration and loss of mass resulting in fractures, chronic pain and physical disability. It is common in postmenopausal women but men are at risk as well for fractures associated with low bone density. The increasing prevalence and cost of treating osteoporosis make the study of safety and effectiveness for currently available osteoporosis therapies pertinent and timely. In 2012, the Agency for Healthcare Research and Quality (AHRQ) published an updated review on the effectiveness and safety of treatments for osteoporosis, including new therapies for the prevention of vertebral and nonvertebral fractures in postmenopausal women and men.The interventions assessed in the review included 1 biological agent, pharmacological agents, dietary and supplemental calcium and vitamin D, and weight-bearing exercise. The updated report included the new agents and indications approved after the 2007 report and new data on effectiveness and adverse events associated with the bisphosponates; calcitonin was determined by the reviewers to not be appropriate therapy for osteoporosis and was excluded. The updated review examined 5 key questions focused on comparative review of all FDA-approved medicines for osteoporosis in fracture risk reduction, effectiveness in racial/ethnic subpopulations as well as different risk stratification using FRAX (World Health Organization Fracture Risk Assessment Tool) or other cutoffs, compliance and adherence, adverse effects of medications, the prediction of treatment efficacy using bone mineral density (BMD) monitoring by dual energy x-ray absorptiometry (DXA), and comparative effectiveness of long-term therapy.The AHRQ reviewers found high strength of evidence to support a reduction in risk of vertebral, nonvertebral and hip fractures in postmenopausal women with osteoporosis treated with 1 of 4 agents (alendronate, risedronate, zoledronic acid, or denosumab). A risk reduction for vertebral fractures in postmenopausal women with osteoporosis treated with ibandronate, teriparatide, or raloxifene therapy was supported with high-strength evidence. Evidence was graded high strength for reduction of vertebral and hip fracture with estrogen therapy in postmenopausal women but not in women with established osteoporosis. Evidence was graded moderate for a reduction in nonvertebral fractures with teriparatide or calcium monotherapy. Moderate or low-moderate strength of evidence showed that calcium alone does not reduce the risk of vertebral or nonvertebral fracture, and that vitamin D has mixed results on decreasing overall fracture risk. High-strength evidence supports a reduction in the risk of hip fracture with calcium treatment. Vitamin D treatment significantly reduced vertebral fractures among patients with primary osteoporosis. The combination of calcium plus vitamin C did not reduce vertebral fracture risk, but did reduce nonvertebral fracture risk in certain populations. Calcium plus vitamin D did decrease the risk of fracture in elderly women but not in elderly men. Adherence and persistence to osteoporosis medications varied depending on patient age, prior history of fracture, dosing frequency, concomitant use of other medications, and adverse effects. Adherence to treatment improved with weekly dosing compared with daily regimens, but evidence was lacking to show monthly regimens improved adherence over weekly regimens. This article recaps the key findings from the AHRQ 2012 review for the purpose of informing health care providers about the efficacy and safety of therapies used to prevent osteoporotic vertebral, nonvertebral, hip, and wrist fractures. Scientific literature on the effects of risk factors, adherence, BMD monitoring, and long-term therapy on patient outcomes is reviewed in order to inform prescribing decisions. In addition, applications of the AHRQ findings to practice are discussed to provide clinicians with information needed to provide evidence-based care for their patients. Prostate cancer (PC) is the leading cause of cancer and the second leading cause of cancer-death among men in the Western world. About 10-20% of men with PC present with metastatic disease at diagnosis, while 20-30% of patients diagnosed with localized disease will eventually develop metastases. Although most respond to initial androgen-deprivation therapy (ADT), progression to castration-resistant PC (CRPC) is universal. In 2004 the docetaxel/prednisone regimen was approved for the management of patients with metastatic CRPC, becoming the standard first-line therapy. Recent advances have now led to an unprecedented number of new drug approvals within the past years, providing many new treatment options for patients with metastatic CRPC. Four new drugs have received U.S. Food and Drug Administration (FDA)-approval in 2010 and 2011: sipuleucel-T, an immunotherapeutic agent; cabazitaxel, a novel microtubule inhibitor; abiraterone acetate, a new androgen biosynthesis inhibitor; and denosumab, a bone-targeting agent. The data supporting the approval of each of these agents are described in this review, as are current approaches in the treatment of metastatic CRPC and ongoing clinical trials of novel treatments and strategies. Prostate cancer is the second leading cause of cancer death in men in the western world. Most deaths will occur due to the progression of cancer into a hormone refractory state. Until recently, docetaxel-based chemotherapy was the only established treatment (shown to increase survival) for patients with metastatic hormone refractory prostate cancer. The improved understanding of prostate cancer biology in recent years led to the development of drugs directed against precise tumorigenesis-associated molecular pathways, and significant expansion of treatment horizons for these patients. In 2010-2011, three more agents, with different mechanisms of action, were shown to be associated with a survival benefit in mHRPC, including the dendritic cell vaccine sipuleucel-T (immunotherapy), the 17,20 lyase inhibitor abiraterone (hormonal therapy), and the taxane cabazitaxel (chemotherapy). A fourth agent, denosumab (bone targeted therapy) was also recently approved by the FDA for patients with bone metastasis after showing a reduction in the occurrence of skeletal-related events. This review will focus on recent advances in the standard treatments paradigm in mHRPC. Worldwide over 12 million people were diagnosed with cancer (excluding non-melanoma skin cancer) and 8 million individuals died from cancer in 2008. Recent data indicate that 75-90% of patients with advanced stage diseases or metastatic cancer will experience significant cancer pain. Bone cancer pain is common in patients with advanced breast, prostate, and lung cancer as these tumors have a marked affinity to metastasize to bone. Once tumors metastasize to bone, they are a major cause of morbidity and mortality as the tumor induces significant skeletal remodeling, fractures, pain and anemia; all of which reduce the functional status, quality of life and survival of the patient. Currently, the factors that drive cancer pain are poorly understood, however, several recently introduced models of bone cancer pain that mirror the human condition, are providing insight into the mechanisms that drive bone cancer pain and guiding the development of novel therapies to treat the cancer pain. Several of these therapies have recently been approved by the FDA to treat bone cancer pain (bisphosphonates, denosumab) and others are currently being evaluated in human clinical trials (tanezumab). These new mechanism-based therapies are enlarging the repertoire of modalities available to treat bone cancer pain and improving the quality of life and functional status of patients with bone cancer. OBJECTIVE: To review information pertinent to bone health and osteoporosis in men. METHODS: A review of pertinent literature was conducted. RESULTS: Osteoporosis affects approximately 2 million men in the US and accounts for an estimated 600,000 fractures each year. There are significant differences in skeletal size and structure between men and women that account for differences in fracture incidence, location, and outcomes. Bone density testing is appropriate for men age 70 and older and younger men (50-69) who have risk factors for osteoporosis. Lifestyle management, including adequate calcium and vitamin D intake, appropriate physical activity, and avoidance of tobacco and heavy alcohol use, is appropriate for all men. Pharmacologic therapy to reduce fracture risk is advisable for men with a clinical diagnosis of osteoporosis (a spine or hip fracture) or a T-score of -2.5 or below in the spine, femoral neck, total hip or 1/3 radius; however, the majority of men at high risk will only be identified using a fracture risk assessment tool, such as FRAX. Alendronate, risedronate, zoledronic acid, denosumab, and teriparatide are Food and Drug Administration (FDA)-approved therapeutic options. CONCLUSIONS: Osteoporosis in men presents an important public health problem with significant morbidity and mortality. There are recommended strategies for identifying men at high risk of fracture, and effective agents are available for treatment. In women with advanced breast cancer, approximately three-quarters develop metastases to the bone, with a median survival after diagnosis of 2-3 years. Receptor activator of nuclear factor-κB (RANK) and RANK ligand (RANKL) belong to a signal pathway highly implicated in the development of bone metastases. Denosumab, a human monoclonal antibody with high affinity and specificity for RANKL, prevents the RANKL/RANK interaction and inhibits osteoclast formation and function, thereby decreasing bone resorption and increasing bone mass. Denosumab compared with zoledronic acid showed superior efficacy in delaying time to first-on study SRE and time to first- and subsequent-on study SREs as well as reduction in bone turnover markers. These results led to the approval of denosumab by the European Medicines Agency (EMA) and the US Food and Drug Administration (FDA), for the prevention of SREs in adults with bone metastases from solid tumors, including breast cancer. Postmenopausal osteoporosis is a major concern to public health. Fractures are the major clinical consequence of osteoporosis and are associated with substantial morbidity, mortality and health care costs. Bone strength determits such as bone mineral density and bone quality parameters are determined by life-long remodeling of skeletal tissue. Receptor activator of nuclear factor-kB ligand (RANKL) is a cytokine essential for osteoclast differentiation, activation and survival. Denosumab (Prolia®) is a fully human monoclonal antibody for RANKL, which selectively inhibits osteoclastogenesis, being recently approved for the treatment of postmenopausal osteoporosis in women at a high or increased risk of fracture by the FDA in the United States and by the European Medicines Agency in Europe since June 2010. FREEDOM, DECIDE and STAND are the phase 3 trials comparing denosumab with placebo and alendronate in postmenopausal osteoporosis. The authors aim to update denosumab role in postmenopausal osteoporosis with a physiopathological review. Giant cell tumor of bone (GCTB) is an osteolytic, usually benign neoplasm characterized by infiltration with osteoclast-like giant cells, and the osteoclast differentiation factor receptor activator of nuclear factor kappa-B ligand (RANKL) is heavily involved in its pathogenesis. Denosumab belongs to a new class of drugs that inhibit RANKL. Prior to denosumab, multimodality treatment in refractory, recurrent and metastatic GCTB has shown variable results. Recent phase II data have demonstrated denosumab's activity with regard to disease and symptom control, without significant adverse effects. On the basis of this data, the FDA approved denosumab for the treatment of patients whose GCTB is unresectable, or when surgery is likely to result in severe morbidity. Ongoing questions remain, including the optimal scheduling, patient selection, use in the adjuvant setting and long-term toxicity concerns. BACKGROUND CONTEXT: Denosumab (XGeva) is a receptor activator of nuclear factor-κB ligand (RANKL)-antibody that was approved by the Food and Drug Administration (FDA) in 2010 for the prevention of skeletal fractures in patients with bone metastases from solid tumors. Although there is a widespread use of such drug in patients under risk of pathological fractures, the compatibility of denosumab therapy with percutaneous vertebroplasty (an interventional procedure commonly used for pain control in such population) has not yet been established. PURPOSE: To present the serial imaging findings and technical report of an attempted percutaneous vertebroplasty in a patient with refractory pain and a lytic pathological vertebral fracture related to small cell lung cancer spinal metastasis and who was actively under medical treatment with denosumab. STUDY DESIGN: Retrospective review and case report. METHODS: The authors present the imaging findings and technical report of an attempted percutaneous vertebroplasty in the only patient found to be actively under treatment with denosumab after a retrospective review of the databank of patients with pathological fractures referred to the Department of Radiology of the Ohio State University for percutaneous vertebroplasty (a total sample of 20 patients) since the FDA approval of denosumab (November 2010) until June 2013 (a 30-month period). RESULTS: Although the computed tomography scan of the thoracic spine, performed 6 weeks after the initiation of the treatment with denosumab, presented a remarkable remodeling of the previously lytic vertebral lesion (which became markedly sclerotic in appearance), the clinical response in terms of pain improvement was not satisfactory. At the time of the percutaneous vertebroplasty (which was indicated for pain control), after advancing the 11-gauge needle through the pedicle with extreme difficulty, the needle repeatedly deviated laterally and, despite several attempts, it was not possible to penetrate the vertebral body and perform the cement injection. CONCLUSIONS: This is the first report of the technical peculiarities of percutaneous vertebroplasty in patients under medical treatment with denosumab. According to our experience, because of its RANKL-mediated effects on osteoclasts activity, denosumab has been shown to induce a fast and marked sclerotic response on vertebral bodies that may not be accompanied by a satisfactory improvement in pain control (especially in patients with mechanical type of pain) and which may actually prevent the successful performance of percutaneous vertebroplasty. Therefore, it is of paramount importance that future studies evaluating patients with vertebral fractures under treatment with denosumab include long-term pain outcome measures. Additionally, further investigation is warranted to determine the optimal order of treatment and the best timeframe for combining percutaneous vertebroplasty and denosumab therapy in patients presenting with acute vertebral compression fractures and refractory axial pain.
List the human genes encoding for the dishevelled proteins?
DVL-1 DVL-2 DVL-3
The dishevelled gene of Drosophila is required to establish coherent arrays of polarized cells and is also required to establish segments in the embryo. Here, we show that loss of dishevelled function in clones, in double heterozygotes with wingless mutants and in flies bearing a weak dishevelled transgene leads to patterning defects which phenocopy defects observed in wingless mutants alone. Further, polarized cells in all body segments require dishevelled function to establish planar cell polarity, and some wingless alleles and dishevelled; wingless double heterozygotes exhibit bristle polarity defects identical to those seen in dishevelled alone. The requirement for dishevelled in establishing polarity in cell autonomous. The dishevelled gene encodes a novel intracellular protein that shares an amino acid motif with several other proteins that are found associated with cell junctions. Clonal analysis of dishevelled in leg discs provides a unique opportunity to test the hypothesis that the wingless dishevelled interaction species at least one of the circumferential positional values predicted by the polar coordinate model. We propose that dishevelled encodes an intracellular protein required to respond to a wingless signal and that this interaction is essential for establishing both cell polarity and cell identity. The Drosophila dishevelled gene (dsh) encodes a secreted glycoprotein, which regulates cell proliferation, acting as a transducer molecule for developmental processes, including segmentation and neuroblast specification. We have isolated and characterized cDNA clones from two different human dsh-homologous genes, designated as DVL-1 and DVL-3. DVL-1 and DVL-3 putative protein products show 64% amino acid identity. The DVL-1 product is 50% identical to dsh and 92% to a murine dsh homologue (Dvl-1). Both human DVL genes are widely expressed in fetal and adult tissues, including brain, lung, kidney, skeletal muscle and heart. DVL-1 locus maps to chromosome 1p36 and DVL-3 to chromosome 3q27. DVL-1 locus on chromosome 1 corresponds to the murine syntenic region where Dvl-1 is located. DVL-1 and DVL-3 are members of a human dsh-like gene family, which is probably involved in human development. Although the precise role of these genes in embryogenesis is only conjectural at present, the structural and evolutionary characteristics suggest that mutations at their loci may be involved in neural and heart developmental defects. The Wnt family of proto-oncogenes encodes secreted signaling proteins that are required for mouse development. The Drosophila Wnt homolog, the wingless (Wg) segment polarity gene, mediates a signal transduction pathway in which the downstream elements appear to be conserved through evolution. One such element, the dishevelled gene product, becomes hyperphosphorylated and translocates to the plasma membrane in response to Wg (Yanagawa et al., 1995). We report here that the mouse Dishevelled-1 (Dvl-1) and Dishevelled-2 genes encode proteins that are differentially localized in Wnt-overexpressing PC12 cell lines (PC12/Wnt). Whereas Dvl-1 and Dvl-2 proteins are limited to the soluble fraction of parental PC12 cells, PC12/Wnt cells display a subset of Dvl-1 protein associated with the membrane and Dvl-2 protein with the cytoskeletal fraction. These results suggest a conserved role for Dvl in Wnt/wg signal transduction. The Dvl-1 gene on chromosome 1p36 belongs to a family of highly conserved secreted proteins which regulates embryonic induction, generation of cell polarity and specification of cell fate through activation of Wnt signaling pathways. Wnt signaling activates the gene encoding DVL-1; the latter suppresses beta-catenin by promoting its degradation through enhanced inactivation of glycogen-synthase-kinase 3 (GSK3). Here we demonstrate increased expression of DVL-1 mRNA in over two thirds of primary cervical squamous cell cancers (11 of 15 cases) when compared to corresponding non-cancerous uterine squamous cell tissues. In addition, we noted up-regulation of cyclin D1, a downstream effector of Wnt signal pathway in cervical cancer. Immunohistochemical staining demonstrated that DVL-1 protein was prominent in the cytoplasm of cancer cells whereas it was unreactive in the surrounding normal cervical squamous cells. These data indicate that amplification and increased expression of the DVL-1 gene may play some role in the development of a portion of human cervical squamous cell cancer through derangement of the Wnt signaling pathway. AIMS AND BACKGROUND: The Wnt/beta-catenin signaling pathway is one of the main carcinogenic mechanisms in human maligcies including prostate cancer. Recently, the DVL1 gene was identified as a middle molecule of the Wnt/beta-catenin signaling pathway. In addition, alterations of the DVL1 gene have been reported in breast and cervical cancer. The abnormality of beta-catenin in prostate cancer has been well studied, so the examination of the DVL1 gene in prostate cancer is appealing. METHODS: We investigated DVL1 messenger RNA alterations by semiquantitative PCR (SQ-PCR) in 20 primary prostate cancers and assessed the protein expression by immunohistochemical analysis in the same samples. In addition, DVL1 and beta-catenin protein expression was evaluated with a new validated set of 20 prostate cancers. RESULTS: SQ-PCR revealed significant overexpression of DVL1 in prostate cancer (65%). Upregulation of the DVL1 gene product in prostate cancer was confirmed by immunostaining. With SQ-PCR and immunostaining, none of the cases showed underexpression or downregulation of DVL1. In addition, the data showed correlations between DVL1 mRNA and protein expression. Interestingly, the expression level of DVL1 increased with worsening histological grade. In addition, a correlation between DVL1 expression and beta-catenin expression was confirmed. CONCLUSIONS: DVL1 was overexpressed in prostate cancer and its overexpression might be related to prostate cancer progression through the Wnt/beta-catenin pathway. Dishevelled (Dvl) proteins are key transducers of Wnt signaling encoded by members of a multi-gene family in vertebrates. We report here the divergent, tissue-specific expression patterns for all three Dvl genes in Xenopus embryos, which contrast dramatically with their expression patterns in mice. Moreover, we find that the expression patterns of Dvl genes in the chick diverge significantly from those of Xenopus. In addition, in hemichordates, an outgroup to chordates, we find that the one Dvl gene is dynamically expressed in a tissue-specific manner. Using knockdowns, we find that Dvl1 and Dvl2 are required for early neural crest specification and for somite segmentation in Xenopus. Most strikingly, we report a novel role for Dvl3 in the maintece of gene expression in muscle and in the development of the Xenopus sclerotome. These data demonstrate that the expression patterns and developmental functions of specific Dvl genes have diverged significantly during chordate evolution. Hirschsprung's disease (HSCR) is a congenital disorder of the enteric nervous system and is characterized by an absence of enteric ganglion cells in terminal regions of the gut during development. Dishevelled (DVL) protein is a cytoplasmic protein which plays pivotal roles in the embryonic development. In this study, we explore the cause of HSCR by studying the expression of DVL-1 and DVL-3 genes and their proteins in the aganglionic segment and the ganglionic segment of colon in HSCR patients. MATERIALS AND METHODS: Specimen of aganglionic segment and ganglionic segment of colon in 50 cases of HSCR patients. Expression levels of mRNA and proteins of DVL-1 and DVL-3 were confirmed by quantitative real-time PCR (qRT-PCR), western blot and immunohistochemistry staining between the aganglionic segment and the ganglionic segment of colon in HSCR patients. RESULTS: The mRNA expression of DVL-1 and DVL-3 were 2.06 fold and 3.12 fold in the aganglionic segment colon tissues compared to the ganglionic segment, respectively. Similarly, the proteins expression of DVL-1 and DVL-3 were higher (39.71 ± 4.53 vs and 53.90 ± 6.79 vs) in the aganglionic segment colon tissues than in the ganglionic segment (15.01 ± 2.66 and 20.13 ± 3.63) by western blot. Besides, immunohistochemical staining showed that DVL-1 and DVL-3 have a significant increase in mucous and submucous layers from aganglionic colon segments compared with ganglionic segments. CONCLUSION: The study showed an association of DVL-1 and DVL-3 with HSCR, it may play an important role in the pathogenesis of HSCR.
Name synonym of Acrokeratosis paraneoplastica.
Acrokeratosis paraneoplastic (Bazex syndrome) is a rare, but distinctive paraneoplastic dermatosis characterized by erythematosquamous lesions located at the acral sites and is most commonly associated with carcinomas of the upper aerodigestive tract.
Acrokeratosis paraneoplastica of Bazex is a rare cutaneous syndrome associated with maligt neoplasms of the pulmonary and upper gastrointestinal tract, or cervical metastatic adenopathy, usually seen in middle-aged white men. We present a unique case of Bazex syndrome in that the patient was young, black, and a woman. A 55-year-old white man born in Canada presented with all the clinical features of acrokeratosis paraneoplastica of Bazex. He showed the characteristic violaceous erythema and scaling of the nose and face, the aural helices, and the palmoplantar regions with severe nail dystrophy. Extensive examinations failed to reveal any associated maligcy up to 5 months after the onset of the skin eruption. While the skin was improving, and although the patient was still asymptomatic except for a weight loss of 5 kg, evidence of metastatic squamous cell carcinoma of the cervical region was obtained. Only palliative treatment could be undertaken. The bizarre clinical aspects of the syndrome are reviewed. Acrokeratosis paraneoplastica (Bazex' syndrome) is a rare but clinically distinctive dermatosis that has been associated in all reported cases, to our knowledge, with either a primary maligt neoplasm of the upper aerodigestive tract or metastatic cancer to the lymph nodes of the neck. Acrokeratosis paraneoplastica was found in a 53-year-old black man with squamous cell carcinoma of the tonsil. A distinctive series of changes was found on histopathologic examination of biopsy specimens taken from his skin lesions, and direct immunofluorescence microscopy of both lesional and nonlesional skin specimens showed immunoglobulin and complement deposition on the epidermal basement membrane. The skin lesions largely resolved following radiation therapy of the neoplasm and of the presumably involved lymph nodes. The focus of this article is acrokeratosis paraneoplastica, one of two disorders that have acquired the eponym Bazex syndrome. To date, all of the patients reported in the literature have had an underlying neoplasm, most commonly squamous cell carcinoma of the upper aerodigestive tract. In this review of 113 cases of acrokeratosis paraneoplastica (mean age, 61 years; 105 males, 8 females), the psoriasiform lesions preceded the diagnosis of the associated maligcy in 73 (67%) of 109 patients, whereas the cutaneous manifestations followed the diagnosis of the neoplasm in only 16 (15%) of 109; in the remainder, the onset of the skin lesions and the diagnosis of the tumor occurred simultaneously. Therefore, awareness of the cutaneous signs of Bazex syndrome is of obvious importance to dermatologists. Evidence in favor of the paraneoplastic nature of this disease is as follows: in 81 (93%) of 87 patients with adequate clinical descriptions, the skin lesions either improved significantly (or resolved) when the underlying neoplasm was treated or they remained unchanged in the setting of persistent disease. Occasionally, the reappearance of skin lesions has signaled a recurrence of the tumor. A 65-year-old white man presented with all the clinical features of acrokeratosis paraneoplastica of Bazex, characterized by violaceous erythema and scaling of the nose, aural helices, fingers, and toes, with keratoderma and severe nail dystrophy. Examination of the patient for possible associated maligcy disclosed an asymptomatic squamous cell carcinoma at the oropharyngeal region. The skin lesions resolved almost completely following radiation therapy of the neoplasm, but the onychodystrophy persisted. This case report illustrates the importance of early recognition of Bazex syndrome. Bazex syndrome, or acrokeratosis paraneoplastica, is a cutaneous paraneoplastic syndrome characterized by psoriasiform lesions associated with, usually, a squamous cell carcinoma of the upper aerodigestive tract. We present a case of Bazex syndrome associated with metastatic cervical squamous cell carcinoma with an unknown primary. The features of the condition are discussed in the light of current knowledge. PURPOSE: Obligatory cutaneous paraneoplastic disorders comprising acanthosis nigricans maligna, erythema gyratum repens, paraneoplastic pemphigus, hypertrichosis lanuginosa acquisita, erythema necrolyticum migrans and acrokeratosis paraneoplastica are rare. However, as markers of an underlying internal maligcy they are of utmost importance for the patient. Acrokeratosis paraneoplastica (first described by Gougerot and Rupp in 1922) was named after Bazex who had then reported several cases in a French dermatological journal since 1965 (Bazex et al. in Bull Soc Fr Dermatol Syphiligr 72:182, 1965; Bazex and Griffiths in Br J Dermatol 102:301-306, 1980). METHOD: The study is a clinical case of a patient with acrokeratosis paraneoplastica. RESULTS: the patient was later diagnosed with a cervical lymph node metastasis and thereafter with a primary squamous cell carcinoma of the left upper lobe and upon treatment responded with the clearing of the skin changes. CONCLUSION: Identification of a paraneoplastic syndrome may enhance the earlier diagnosis of the associated tumor and may thus enable curative treatment. Acrokeratosis paraneoplastica (Bazex's syndrome) is a rare obligate paraneoplastic dermatosis characterized by erythematosquamous lesions localized symmetrically at the acral sites. The condition almost exclusively affects Caucasian men older than 40 years. It is usually associated with primary maligt neoplasms of the upper aerodigestive tract. In most cases, the skin changes precede the clinical manifestation of the underlying neoplasm. The dermatosis can be cured only by removal of the underlying carcinoma. We describe a case of acrokeratosis paraneoplastica associated with a retroperitoneal liposarcoma in a 71-year-old Caucasian man. The liposarcoma was surgically removed but recurred several times, with acrokeratosis paraneoplastica showing a parallel development. We, therefore, add liposarcoma to the growing list of maligt neoplasms associated with acrokeratosis paraneoplastica. BACKGROUND: Bazex syndrome (acrokeratosis paraneoplastica) is a rare paraneoplastic syndrome that usually occurs in males over 40 years old and is particularly associated with squamous cell carcinoma of the upper aerodigestive tract and adenopathy above the diaphragm. OBJECTIVE: The objectives of our article are (1) to describe a unique case of acrokeratosis paraneoplastica and (2) to review the current literature regarding skin findings, commonly associated neoplasms, and treatment options relative to this condition. PATIENT: We describe a 68-year-old female with lobular breast carcinoma, complicated by local and distant recurrences, who presented with a 1-year history of prominent acral skin and nail changes. RESULTS: Our patient's clinical skin findings improved significantly following treatment and partial remission of her underlying maligcy. CONCLUSIONS: Our patient represents one of few females described with this syndrome, which is especially rare in association with lobular breast carcinoma. Further, the patient's presentation is unique as she was discovered to demonstrate laboratory findings consistent with coexistent porphyria cutanea tarda and relative zinc deficiency. BACKGROUND: Acrokeratosis paraneoplastica Bazex (APB) is a very rare disease in the group of obligate paraneoplastic dermatoses, associated mostly with squamous cell carcinoma of the upper aerodigestive tract and metastatic cervical lymphadenopathy. The disease is characterized by violaceous erythemosquamous changes on the acral regions. This entity was first reported by Bazex in 1965. About 160 cases have been presented so far. CASE REPORT: We presented a patient with a three-month history of violaceous erythema, edema, erosions and scaling on the acral regions, elbows and knees and severe nail dystrophy. When the diagnosis was established, he did not have any symptom of internal maligcy. Esophagogastroscopy revealed ulcerovegetant lesion of the esophagus, while histology showed squamocellular invasive carcinoma. Surgical tumor removal resulted in significant improvement of skin changes in 15 days. Unfortunately, four months later, extensive skin lesions pointed to metastasis of squamous cell carcinoma. CONCLUSION: Skin changes can precede a few years the first manifestations of neoplasia. The course of the disease in our patient proved that APB is a specific marker of underlying maligcy. Acrokeratosis paraneoplastica is a rare paraneoplastic syndrome commonly affecting males over 40 years of age. There exists a strong association with squamous cell carcinoma (SCC) of the upper aerodigestive tract or cervical metastatic disease originating from an unknown primary. We report a case associated with SCC of the right tonsil with persistent paraneoplastic cutaneous lesions 2 years after successful treatment of the underlying neoplasm. Acrokeratosis paraneoplastic (Bazex syndrome) is a rare, but distinctive paraneoplastic dermatosis characterized by erythematosquamous lesions located at the acral sites and is most commonly associated with carcinomas of the upper aerodigestive tract. We report a 58-year-old female with a history of a pigmented rash on her extremities, thick keratotic plaques on her hands, and brittle nails. Chest imaging revealed a right upper lobe mass that was proven to be small cell lung carcinoma. While Bazex syndrome has been described in the dermatology literature, it is also important for the radiologist to be aware of this entity and its common presentations.
Which are the classes of anti-arrhythmic drugs according to Vaughan-Williams classification?
Antiarrhythmic drugs can be divided into four Vaughan Williams classes (I-IV). Class I antiarrhythmic agents have as a common action, blockade of the sodium channels. Class II agents are antisympathetic drugs, particularly the beta-adrenoceptor blockers. Class-III antiarrhythmics have as a common action the potassium-channel blockade. Class IV antiarrhythmic drugs are calcium channel blockers.
The present paper reviews classification and mode of action of agents that suppress extrasystoles and tachyarrhythmias. These are classified according to their electrophysiological effects observed in isolated cardiac tissues in vitro (Vaughan Williams, 1989). Fast sodium channel blockers (class I) which reduce the upstroke velocity of the action potential are usually subclassified into three groups, class I A-C, according to their effect on the action potential duration. Beta-adrenergic antagonists (class II) exert their effects by antagonizing the electrophysiological effects of beta-adrenergic catecholamines. Class III antiarrhythmic agents (eg amiodarone) prolong the action potential and slow calcium channel blockers (class IV) suppress the calcium inward current and calcium-dependent action potentials. The classification of antiarrhythmic drugs is still under debate. This particularly applies to agents of class I and III. The effect of class I agents is frequency-dependent because the binding affinity of these drugs to the sodium channel is modulated by the state of the channel (modulated receptor hypothesis). Class I agents bind to the channel in the activated and inactivated state and dissociate from the channel in the rested state. This occurs at a drug-specific rate so that class I agents can be subclassified into only two groups, namely in those of the slow- and fast-recovery type respectively (time constant of reactivation greater or smaller than 1 s). Slow-recovery class I agents affect regular action potentials at normal heart rates which can more easily lead to a lengthening of the QRS duration in the ECG, to conduction disturbances and hence to pro-arrhythmic effects.(ABSTRACT TRUNCATED AT 250 WORDS) Antiarrhythmic drugs can be divided into four Vaughan Williams classes (I-IV) according to defined electrophysiological effects on the myocardium. Thus, the Vaughan Williams classification also coincides with the main myocardial targets of the antiarrhythmics, i.e., myocardial sodium-, potassium-, and calcium-channels or beta-adrenergic receptors. A more detailed characterization which is also based on the myocardial targets of a drug is given by the "Sicilian Gambit" approach of classification. Nevertheless, the appropriate drug for the management of a given clinical arrhythmia has to be chosen according to the electrophysiological effects of the respective drug. A main determit of the antiarrhythmic or proarrhythmic properties of a drug is the frequency dependence of its electrophysiological effects. The sodium-channel blockade induced by class-I substances is enhanced with increasing heart rates. Thus, class-I antiarrhythmics can be subclassified as substances showing a more exponential, an approximately linear, or rather saturated block-frequency relation. Class-III antiarrhythmics (potassium-channel blockade) can be further differentiated according to the component of the delayed rectifier potassium current (IK) which is inhibited by a drug. Class-III drugs inhibiting selectively the rapidly activating and deactivating IKr component exhibit a marked reverse rate dependence, i.e., the drug induced prolongation of the cardiac action potential is minimized at high rates. On the other hand, during bradycardia the pronounced action potential prolongation may cause early afterdepolarizations and triggered activity leading to torsades de pointes arrhythmias (acquired QT syndrome). Class-III substances inhibiting the slowly activating IKs component are currently under investigation and are expected to show a direct rate dependence. Experimental data available so far point to an action potential prolonging effect at least independent of rate. However, it is uncertain whether proarrhythmic effects can be thus avoided, especially in light of the fact that one form of congenital QT syndrome (LQT1) seems to be linked to dysfunction of the IKs-channel. Antiarrhythmic agents are traditionally classified according to Vaughan Williams into four classes of action. Class I antiarrhythmic agents include most of the drugs traditionally thought of as antiarrhythmics, and have as a common action, blockade of the fast-inward sodium channel on myocardium. These agents have a very significant toxicity, and while they are being used less, therapeutic drug monitoring (TDM) does significantly increase the safety with which they can be administered. Class II agents are antisympathetic drugs, particularly the b-adrenoceptor blockers. These are generally safe agents which do not normally require TDM. Class III antiarrhythmic agents include sotalol and amiodarone. TDM can be useful in the case of amiodarone to monitor compliance and toxicity but is generally of little value for sotalol. Class IV antiarrhythmic drugs are the calcium channel blockers verapamil and diltiazem. These are normally monitored by haemodynamic effects, rather than using TDM. Other agents which do not fall neatly into the Vaughan Williams classification include digoxin and perhexiline. TDM is very useful for monitoring the administration (and particularly the safety) of both of these agents.
Which are the different isoforms of the mammalian Notch receptor?
Notch signaling is an evolutionarily conserved mechanism, used to regulate cell fate decisions. Four Notch receptors have been identified in man: Notch-1, Notch-2, Notch-3 and Notch-4.
Notch signaling is an evolutionarily conserved mechanism, used to regulate cell fate decisions. Four Notch receptors have been identified in man (Notch-1 to -4). In this study, semiquantitative reverse transcription polymerase chain reaction (RT-PCR) and immunohistochemistry were used to examine the expression pattern of Notch receptor genes in whole adult human liver and isolated liver cell preparations. All 4 receptors were expressed in the adult liver, with no significant differences in the levels of Notch-1, -2, and -4 messenger RNA (mRNA) between normal and diseased liver. However, Notch-3 expression appeared to be increased in diseased tissue. The distribution of Notch-1 and -4 in normal tissue was similar, with Notch-1 also detectable at low levels in the sinusoidal endothelium. Notch-2 expression was more widely distributed, and detectable in hepatocytes, medium-sized bile ducts, and the sinusoidal endothelium. Notch-3 expression was seen on hepatocytes, with weaker expression detectable in portal veins, hepatic arteries, and the sinusoids. In normal liver tissue Notch-1, -2, and -3 were found to be coexpressed on bile duct epithelium; however, with the exception of Notch-3 in primary sclerosing cholangitis (PSC) livers, expression was absent on proliferating ductules in all disease states examined. Interestingly, the expression of Notch-2 and -3 was associated with numerous small vessels within the portal tract septa of diseased tissue. The absence of Notch receptor expression on proliferating bile ductules and its presence on neovessels suggests that Notch signaling may be important for normal bile duct formation and the aberrant neovascularization seen in diseased liver tissue. BACKGROUND: The interaction of Notch receptors with their transmembrane ligands Delta and Jagged plays an important role not only in the organization of a variety of tissues but also in several genetic disorders and cancer development. The functional involvement of the Notch signaling in rheumatoid arthritis (RA) has been reported previously, but the expression profile of Notch-related molecules, as well as their relation with clinicopathological parameters, remains unclear. METHODS: In this study, we analyzed the immunohistochemical staining pattern of four Notch receptors (Notch1-4) and their ligands (Delta1 and Jagged1) in 14 synovial tissues obtained from 14 RA patients. RESULTS: Notch2 and Notch4 were expressed in limited areas in a few samples or in small blood vessels, respectively. Notch1, Notch3, Delta1, and Jagged1 were overexpressed in the synovial lining and sublining cells on synovial hyperplastic lesions in all samples. Notch1 expression was also observed in T and B lymphocytes of lymphoid follicles independently. Notch1 and Notch3 expression overlapped with that of Jagged1, as determined by confocal microscopy. Activation of Notch1 signaling in the RA synovium was identified using a specific antibody to the cleaved form of Notch1. The expression of these molecules did not show any correlation with clinicopathological parameters. CONCLUSIONS: Our results suggest that Notch signaling is activated in RA synovium but does not necessarily reflect the pathological condition of RA. Hepatoblastoma is a pediatric maligcy characterized by the uncontrolled proliferation of immature hepatocytes (hepatoblasts). This disease is diagnosed primarily in children younger than 5 years and is disproportionately observed in former premature infants. Cytogenetically, hepatoblastoma is characterized by numerical aberrations, as well as unbalanced translocations involving the proximal region of chromosome 1q. The NOTCH2 gene has been mapped to this locus, and it is well established that the NOTCH gene family is an important regulator of several developmental pathways. Specifically, the NOTCH2 protein is known to delay hepatoblast maturation during early hepatic organogenesis, and the reduction of NOTCH2 expression correlates with the differentiation of hepatoblasts into hepatocytes and biliary cells in the developing liver. We hypothesized that NOTCH2 is involved in the pathogenesis of hepatoblastoma by maintaining a population of undifferentiated hepatoblasts. We studied the immunohistochemical expression of NOTCH2 and its isoforms NOTCH1, NOTCH3, and NOTCH4 and the NOTCH2 primary ligand JAGGED1 in hepatoblastomas. Compared with the normal liver, an increased level of NOTCH2 expression was seen in 22 of 24 (92%) hepatoblastomas. There was no significant staining for other NOTCH isoforms and JAGGED1 in hepatoblastomas. Therefore, we suggest that NOTCH2 expression and activation, independent of JAGGED1 expression, may contribute to the pathogenesis of hepatoblastoma. In the hepatoblastoma sinusoidal vasculature, we saw NOTCH3 and NOTCH1 expression. These observations have potential implications with regard to therapeutic targeting of the NOTCH signaling pathway in hepatoblastomas. Notch signalling occurs via direct cell-cell interactions and plays an important role in linking the fates of neighbouring cells. There are four different mammalian Notch receptors that can be activated by five cell surface ligands. The ability to inhibit specific Notch receptors would help identify the roles of individual family members and potentially provide a means to study and control cell differentiation. Anti-Notch antibodies in the form of single chain Fvs were generated from an antibody phage display library by selection on either the ligand binding domain or the negative regulatory region (NRR) of Notch1 and Notch2. Six antibodies targeting the NRR of Notch1 and four antibodies recognising the NRR of Notch2 were found to prevent receptor activation in cell-based luciferase reporter assays. These antibodies were potent, highly specific inhibitors of individual Notch receptors and interfered with endogenous signalling in stem cell systems of both human and mouse origin. Antibody-mediated inhibition of Notch efficiently down-regulated transcription of the immediate Notch target gene hairy and enhancer of split 5 (Hes5) in both mouse and human neural stem cells and revealed a redundant regulation of Hes5 in these cells as complete down-regulation was seen only after simultaneous blocking of Notch1 and Notch2. In addition, these antibodies promoted differentiation of neural stem cells towards a neuronal fate. In contrast to the widely used small molecule γ-secretase inhibitors, which block all 4 Notch receptors (and a multitude of other signalling pathways), antibodies allow blockade of individual Notch family members in a highly specific way. Specific inhibition will allow examination of the effect of individual Notch receptors in complex differentiation schemes regulated by the co-ordinated action of multiple signalling pathways. Cerebral Autosomal Domit Arteriopathy with Subcortical Infarcts and Leukoencephalopathy (CADASIL) is the best understood cause of domitly inherited stroke and results from NOTCH3 mutations that lead to NOTCH3 protein accumulation and selective arterial smooth muscle degeneration. Previous studies show that NOTCH3 protein forms multimers. Here, we investigate protein interactions between NOTCH3 and other vascular Notch isoforms and characterize the effects of elevated NOTCH3 on smooth muscle gene regulation. We demonstrate that NOTCH3 forms heterodimers with NOTCH1, NOTCH3, and NOTCH4. R90C and C49Y mutant NOTCH3 form complexes which are more resistant to detergents than wild type NOTCH3 complexes. Using quantitative NOTCH3-luciferase clearance assays, we found significant inhibition of mutant NOTCH3 clearance. In coculture assays of NOTCH function, overexpressed wild type and mutant NOTCH3 significantly repressed NOTCH-regulated smooth muscle transcripts and potently impaired the activity of three independent smooth muscle promoters. Wildtype and R90C recombit NOTCH3 proteins applied to cell cultures also blocked canonical Notch fuction. We conclude that CADASIL mutants of NOTCH3 complex with NOTCH1, 3, and 4, slow NOTCH3 clearance, and that overexpressed wild type and mutant NOTCH3 protein interfere with key NOTCH-mediated functions in smooth muscle cells.
Which are the major characteristics of cellular senescence?
The defining characteristics of cellular senescence are altered morphology, arrested cell-cycle progression, development of aberrant gene expression with proinflammatory behavior, and telomere shortening.
Although reactive oxygen species have been proposed to play a major role in the aging process, the exact molecular mechanisms remain elusive. In this study we investigate the effects of a perturbation in the ratio of Cu/Zn-superoxide dismutase activity (Sod1 dismutases .O2-to H2O2) to glutathione peroxidase activity (Gpx1 catalyses H2O2 conversion to H2O) on cell growth and development. Our data demonstrate that Sod1 transfected cell lines that have an elevation in the ratio of Sod1 activity to Gpx1 activity produce higher levels of H2O2 and exhibit well characterised markers of cellular senescence viz. slower proliferation and altered morphology. On the contrary, Sod1 transfected cell lines that have an unaltered ratio in the activity of these two enzymes, have unaltered levels of H2O2 and fail to show characteristics of senescence. Furthermore, fibroblasts established from individuals with Down syndrome have an increase in the ratio of Sod1 to Gpx1 activity compared with corresponding controls and senesce earlier. Interestingly, cells treated with H2O2 also show features of senescence and/or senesce earlier. We also show that Cip1 mRNA levels are elevated in Down syndrome cells, Sod1 transfectants with an altered Sod1 to Gpx1 activity ratio and those treated with H2O2, thus suggesting that the slow proliferation may be mediated by Cip1. Furthermore, our data demonstrate that Cip1 mRNA levels are induced by exposure of cells to H2O2. These data give valuable insight into possible molecular mechanisms that contribute tribute to cellular senescence and may be useful in the evolution of therapeutic strategies for aging. Recent research has shown that inserting a gene for the protein component of telomerase into senescent human cells reextends their telomeres to lengths typical of young cells, and the cells then display all the other identifiable characteristics of young, healthy cells. This advance not only suggests that telomeres are the central timing mechanism for cellular aging, but also demonstrates that such a mechanism can be reset, extending the replicative life span of such cells and resulting in markers of gene expression typical of "younger" (ie, early passage) cells without the hallmarks of maligt transformation. It is now possible to explore the fundamental cellular mechanisms underlying human aging, clarifying the role played by replicative senescence. By implication, we may soon be able to determine the extent to which the major causes of death and disability in aging populations in developed countries-cancer, atherosclerosis, osteoarthritis, macular degeneration, and Alzheimer dementia--are attributable to such fundamental mechanisms. If they are amenable to prevention or treatment by alteration of cellular senescence, the clinical implications have few historic precedents.
Orteronel was developed for treatment of which cancer?
Orteronel was developed for treatment of castration-resistant prostate cancer.
A novel naphthylmethylimidazole derivative 1 and its related compounds were identified as 17,20-lyase inhibitors. Based on the structure-activity relationship around the naphthalene scaffold and the results of a docking study of 1a in the homology model of 17,20-lyase, the 6,7-dihydro-5H-pyrrolo[1,2-c]imidazole derivative (+)-3c was synthesized and identified as a potent and highly selective 17,20-lyase inhibitor. Biological evaluation of (+)-3c at a dose of 1mg/kg in a male monkey model revealed marked reductions in both serum testosterone and dehydroepiandrosterone concentrations. Therefore, (+)-3c (termed orteronel [TAK-700]) was selected as a candidate for clinical evaluation and is currently in phase III clinical trials for the treatment of castration-resistant prostate cancer. PURPOSE: The androgen receptor pathway remains active in men with prostate cancer whose disease has progressed following surgical or medical castration. Orteronel (TAK-700) is an investigational, oral, nonsteroidal, selective, reversible inhibitor of 17,20-lyase, a key enzyme in the production of androgenic hormones. EXPERIMENTAL DESIGN: We conducted a phase I/II study in men with progressive, chemotherapy-naïve, metastatic castration-resistant prostate cancer, and serum testosterone <50 ng/dL. In the phase I part, patients received orteronel 100 to 600 mg twice daily or 400 mg twice a day plus prednisone 5 mg twice a day. In phase II, patients received orteronel 300 mg twice a day, 400 mg twice a day plus prednisone, 600 mg twice a day plus prednisone, or 600 mg once a day without prednisone. RESULTS: In phase I (n = 26), no dose-limiting toxicities were observed and 13 of 20 evaluable patients (65%) achieved ≥50% prostate-specific antigen (PSA) decline from baseline at 12 weeks. In phase II (n = 97), 45 of 84 evaluable patients (54%) achieved a ≥50% decline in PSA and at 12 weeks, substantial mean reductions from baseline in testosterone (-7.5 ng/dL) and dehydroepiandrosterone-sulfate (-45.3 μg/dL) were observed. Unconfirmed partial responses were reported in 10 of 51 evaluable phase II patients (20%). Decreases in circulating tumor cells were documented. Fifty-three percent of phase II patients experienced grade ≥3 adverse events irrespective of causality; most common were fatigue, hypokalemia, hyperglycemia, and diarrhea. CONCLUSIONS: 17,20-Lyase inhibition by orteronel was tolerable and results in declines in PSA and testosterone, with evidence of radiographic responses. Orteronel (also known as TAK-700) is a novel hormonal therapy that is currently in testing for the treatment of prostate cancer. Orteronel inhibits the 17,20 lyase activity of the enzyme CYP17A1, which is important for androgen synthesis in the testes, adrenal glands and prostate cancer cells. Preclinical studies demonstrate that orteronel treatment suppresses androgen levels and causes shrinkage of androgen-dependent organs, such as the prostate gland. Early reports of clinical studies demonstrate that orteronel treatment leads to reduced prostate-specific antigen levels, a marker of prostate cancer tumor burden, and more complete suppression of androgen synthesis than conventional androgen deprivation therapies that act in the testes alone. Treatment with single-agent orteronel has been well tolerated with fatigue as the most common adverse event, while febrile neutropenia was the dose-limiting toxicity in a combination study of orteronel with docetaxel. Recently, the ELM-PC5 Phase III clinical trial in patients with advanced-stage prostate cancer who had received prior docetaxel was unblinded as the overall survival primary end point was not achieved. However, additional Phase III orteronel trials are ongoing in men with earlier stages of prostate cancer. Author information: (1)Karim Fizazi, Institut Gustave Roussy, University of Paris Sud, Villejuif; Stephane Oudard, Université Paris Descartes, Paris, France; Robert Jones, Institute of Cancer Sciences, University of Glasgow, Glasgow; Johann De Bono, The Institute of Cancer Research, London, United Kingdom; Eleni Efstathiou, University of Athens Medical School, Athens; George Fountzilas, Aristotle University of Thessaloniki School of Medicine, Thessaloniki, Greece; Fred Saad, University of Montreal Hospital Center, Montreal, Canada; Ronald de Wit, Erasmus University Medical Center, Rotterdam, the Netherlands; Felipe Melo Cruz, ABC Foundation School of Medicine, Santo André; Flavio Carcano, Hospital de Cancer de Barretos, Barretos, Brazil; Albertas Ulys, Institut of Oncology, Vilnius University, Vilnius, Lithuania; Neeraj Agarwal, Huntsman Cancer Institute, University of Utah, Salt Lake City, UT; David Agus, University of Southern California, Los Angeles, CA; Daniel P. Petrylak, Yale University Cancer Center, New Haven, CT; Shih-Yuan Lee, Bindu Tejura, Niels Borgstein, Takeda Pharmaceuticals International; Iain J. Webb, Millennium: The Takeda Oncology Company, Cambridge, MA; Robert Dreicer, Cleveland Clinic, Cleveland, OH; Joaquim Bellmunt, University Hospital del Mar-IMIM, Barcelona, Spain. [email protected]. (2)Karim Fizazi, Institut Gustave Roussy, University of Paris Sud, Villejuif; Stephane Oudard, Université Paris Descartes, Paris, France; Robert Jones, Institute of Cancer Sciences, University of Glasgow, Glasgow; Johann De Bono, The Institute of Cancer Research, London, United Kingdom; Eleni Efstathiou, University of Athens Medical School, Athens; George Fountzilas, Aristotle University of Thessaloniki School of Medicine, Thessaloniki, Greece; Fred Saad, University of Montreal Hospital Center, Montreal, Canada; Ronald de Wit, Erasmus University Medical Center, Rotterdam, the Netherlands; Felipe Melo Cruz, ABC Foundation School of Medicine, Santo André; Flavio Carcano, Hospital de Cancer de Barretos, Barretos, Brazil; Albertas Ulys, Institut of Oncology, Vilnius University, Vilnius, Lithuania; Neeraj Agarwal, Huntsman Cancer Institute, University of Utah, Salt Lake City, UT; David Agus, University of Southern California, Los Angeles, CA; Daniel P. Petrylak, Yale University Cancer Center, New Haven, CT; Shih-Yuan Lee, Bindu Tejura, Niels Borgstein, Takeda Pharmaceuticals International; Iain J. Webb, Millennium: The Takeda Oncology Company, Cambridge, MA; Robert Dreicer, Cleveland Clinic, Cleveland, OH; Joaquim Bellmunt, University Hospital del Mar-IMIM, Barcelona, Spain. Collaborators: Troon S, Underhill C, Dittrich C, Krainer M, Kramer G, Loidl W, Pummer K, Belyakovskiy V, Polyakov S, Goeminne JC, Hoekx L, Luyten D, Van Poppel H, Werbrouck P, Azambuja A, Barrios C, Brust L, Cabral Filho S, Carcano F, Cruz F, Damião R, Delgado G, Diógenes Â, Dzik C, Faccio A, de Faria G, Faulhaber A, Ferdes H, Ferreira U, Filho R, Franke F, Girotto G, Koff W, Kussumoto C, Malzyner A, de Moraes A, Padílha S, de Pádua C, Pinto L, Portella M, Reiriz A, da Silva Teixeira V, Vieiralves L, Dimitrov B, Dudov A, Micheva R, Petrov P, Taskova V, Carmel M, Casey R, Chin J, Jacobson A, Jansz G, Kapoor A, Kinahan T, Love W, Martin AG, Saad F, Trachtenberg J, Webster T, Acevedo Gaete A, Arén Frontera O, Leyton Naranjo R, Miranda Benabarre A, Pastor Arroyo P, Neira Reyes L, Ramirez Pinto G, Restrepo Molina J, Grgic M, Babjuk M, Domes L, Jansa J, Lukes M, Pavlik I, Zachoval R, Kahu J, Tamm T, Marttila T, Tammela T, Vaarala M, Vitanen J, Bompas E, Colombel M, Delva R, Deplanque G, Fizazi K, Flechon A, Giroux J, Joly F, Lechevallier E, Mottet Auselo N, Priou F, Roubaud G, Roupret M, Spaeth D, De La Taille A, Tourani JM, Feyerabend S, De Geeter P, Geiges G, Gleißner J, Hammerer P, Klotz T, Kuczyk M, Marin J, Schrader A, Stenzl A, Steuber T, Wirth M, Efstathiou E, Georgoulias V, Hatzimouratidis K, Kalofonos H, Papandreou C, Thanos A, Leung KC, Ng C, Farkas L, Pintér J, McDermott R, Sullivan F, Berger R, Gabizon A, Gez E, Rosenbaum E, Sella A, Semenisty V, Tavdy E, Alabiso O, Ciuffreda L, Fratino L, Sternberg C, Tubaro A, Akakura K, Arai Y, Egawa S, Fujimoto H, Ichikawa T, Kakehi Y, Kitamura H, Maniwa A, Miyanaga N, Mizokami A, Nakatani T, Nishimura K, Niwakawa M, Sato F, Sugiyama T, Suzuki H, Suzuki K, Takahashi S, Tomita Y, Ueda T, Uemura H, Yamaguchi R, Yokomizo A, Yoshimura K, Brize A, Litavnience D, Vjaters E, Jankevicius F, Jievaltas M, Jocys G, Ulys A, Calvo Domínguez D, González Perez J, de Leon Jaen S, Pérez O, Rodriguez Rivera J, Valdés A, Blaisse R, Hamberg A, Loosveld O, Los M, Van Oort I, de la Rosette J, De Vries P, Vrijhof H, de Wit R, Costello S, Davidson P, Fong C, Gilling P, Neill M, Abrill Mendoza G, Cano Rivera J, Garcia Ahumada S, Huaringa Leiva R, Pazos Franco A, Jablonska Z, Kmieciak R, Coelho J, Sousa N, Bucuras C, Cebotaru C, Ciuleanu T, Jinga V, Anatolyevich I, Yurievich P, Hiang T, Sing N, Balaz V, Brezovsky M, Kliment J, Mikulas J, Mincik I, Sokol R, Botha M, Hart G, Kraus P, Landers G, Malan J, Bellmunt J, Castellano D, Climent Duran M, Veiga F, González B, Pérez Gracia J, Valderrama B, Provencio M, Damber JE, Häggman M, Nyman C, Berthold D, Fischer N, Popescu R, Stenner F, Chang YH, Ou YC, Tsai YC, Wu HC, Wu TL, Bondarenko I, Ivashchenko P, Kobets V, Pasiechnikov S, Semenukha V, Sernyak Y, Stus V, Bahl A, Birtle A, Chowdhury S, Crabb S, Dixit S, Elliott P, Hoskin P, Jones R, Khoo V, MacDonald A, Malik Z, O'Sullivan J, Simms M, Stockdale A, Agarwal N, Alter R, Anderson TC, Bailen J, Berry W, Bidair M, Clark W, Cohn AL, Crawford E, DiSimone C, Feliciano L, Fleming MT, Forero L, Friday B, Fruehauf JP, Gelmann E, George D, Gignac G, Given R, Gullo J, Hainsworth J, Hajdenberg J, Haluschak JJ, Hamid O, Hammers H, Hart LL, Hussain A, Hutson TE, Ibrahim E, Jain SK, Khojasteh A, Kohli M, Lara PN Jr, Lilly M, Lipton A, Mackey DW, Mao SS, Mehta AR, Modiano MR, Morris M, Muscato JJ, Nordquist LT, Richards DA, Ryan C, Sartor AO, Schnadig ID, Sieber PR, Singal R, Smith F, Somer B, Srkalovic G, Tagawa S, Tan W, Twardowski P, Van Veldhuizen PJ, Vogelzang N, Watkins DL, Wertheim M, Wong YN, Zhang J. OBJECTIVE: We performed a systematic review of the literature to assess the efficacy and the safety of second-line agents targeting metastatic castration-resistant prostate cancer (mCRPC) that has progressed after docetaxel. Pooled-analysis was also performed, to assess the effectiveness of agents targeting the androgen axis via identical mechanisms of action (abiraterone acetate, orteronel). MATERIALS AND METHODS: We included phase III randomized controlled trials that enrolled patients with mCRPC progressing during or after first-line docetaxel treatment. Trials were identified by electronic database searching. The primary outcome of the review was overall survival. Secondary outcomes were radiographic progression-free survival (rPFS) and severe adverse effects (grade 3 or higher). RESULTS: Ten articles met the inclusion criteria for the review. These articles reported the results of five clinical trials, enrolling in total 5047 patients. The experimental interventions tested in these studies were enzalutamide, ipilimumab, abiraterone acetate, orteronel and cabazitaxel. Compared to control cohorts (active drug-treated or placebo-treated), the significant overall survival advantages achieved were 4.8 months for enzalutamide (hazard ratio for death vs. placebo: 0.63; 95% CI 0.53 to 0.75, P < 0.0001), 4.6 months for abiraterone (hazard ratio for death vs. placebo: 0.66, 95% CI 0.58 to 0.75, P < 0.0001) and 2.4 months for cabazitaxel (hazard ratio for death vs. mitoxantrone-prednisone: 0.70, 95% CI 0.59 to 0.83, p < 0.0001). Pooled analysis of androgen synthesis inhibitors orteronel and abiraterone resulted in significantly increased overall and progression-free survival for anti-androgen agents, compared to placebo (hazard ratio for death: 0.76, 95% CI 0.67 to 0.87, P < 0.0001; hazard ratio for radiographic progression: 0.7, 95% CI 0.63 to 0.77, P < 0.00001). Androgen synthesis inhibitors induced significant increases in risk ratios for adverse effects linked to elevated mineralocorticoid secretion, compared to placebo (risk ratio for hypokalemia: 5.75, 95% CI 2.08 to 15.90; P = 0.0008; risk-ratio for hypertension: 2.29, 95% CI 1.02 to 5.17; P = 0.05). CONCLUSIONS: In docetaxel-pretreated patients enzalutamide, abiraterone-prednisone and cabazitaxel-prednisone can improve overall survival of patients, compared to placebo or to best of care at the time of study (mitoxantrone-prednisone). Agents targeting the androgen axis (enzalutamide, abiraterone, orteronel) significantly prolonged rPFS, compared to placebo. Further investigation is warranted to evaluate the benefit of combination or sequential administration of these agents. Large-scale studies are also necessary to evaluate the impact of relevant toxic effects observed in a limited number of patients (e.g., enzalutamide-induced seizures, orteronel-induced pancreatitis, and others).
Is the monoclonal antibody Trastuzumab (Herceptin) of potential use in the treatment of prostate cancer?
Although is still controversial, Trastuzumab (Herceptin) can be of potential use in the treatment of prostate cancer overexpressing HER2, either alone or in combination with other drugs.
Antibody to the Her-2/neu gene product has been shown to inhibit the growth of breast cancer cells overexpressing Her-2/neu and to have clinical utility in treating breast cancer. We studied a recombit, humanized anti-Her-2/neu antibody (Herceptin) in preclinical models of human prostate cancer. The androgen-dependent CWR22 and LNCaP human prostate cancer xenograft models and androgen-independent sublines of CWR22 were used. Her-2/neu staining of the parental, androgen-dependent, and androgen-independent CWR22 tumors and LNCaP tumors demonstrated variable Her-2/neu expression. Herceptin was administered i.p. at a dose of 20 mg/kg twice weekly after the xenograft had been established. No effect of Herceptin on tumor growth was observed in any of the androgen-independent tumors; however, significant growth inhibition was observed in both of the androgen-dependent xenograft models, CWR22 (68% growth inhibition at the completion of the experiment; P = 0.03 for trajectories of the average tumor volume of the groups) and LNCaP (89% growth inhibition; P = 0.002). There was a significant increase in prostate-specific antigen (PSA) index (ng PSA/ml serum/mm3 tumor) in Herceptin-treated androgen-dependent groups compared with control (CWR22, 18-fold relative to pretreatment value versus 1.0-fold, P = 0.0001; LNCaP, 2.35-fold relative to pretreatment value versus 0.6-fold, P = 0.001). When paclitaxel (6.25 mg/kg s.c., five times/week) was given to animals with androgen-dependent and -independent tumors, there was growth inhibition in each group. Paclitaxel and Herceptin cotreatment led to greater growth inhibition than was seen for the agents individually. Thus, in these prostate cancer model systems, Herceptin alone has clinical activity only in the androgen-dependent tumor and has at least an additive effect on growth, in combination with paclitaxel, in both androgen-dependent and androgen-independent tumors. Response to Herceptin did not correlate with the PSA levels, because the PSA index markedly increased in the Herceptin-treated group, whereas it remained constant in the control group. These results suggest the utility of Herceptin in the treatment of human prostate cancer. The HER2/neu oncogene is overexpressed in human pancreatic cancer, but the clinical significance of that overexpression is uncertain. In the present study we investigated the antitumor efficacy of Herceptin, a new recombit humanized anti-HER2/neu antibody, which exhibits cytostatic activity on breast and prostate cancer cells that overexpress the HER2 oncogene. That antibody may retard tumor growth in certain patients with those diseases. We quantified HER2 expression in various human pancreatic cancer cell lines and studied the bioactivity of this antibody both in vitro and in vivo. Growth inhibition by Herceptin was observed in vitro in cell lines with high levels of HER2/neu expression. Cell lines with low levels of this protein did not respond significantly to the antibody. In vivo we studied two different pancreatic cancer cell lines in an orthotopic mouse model of the disease. Herceptin treatment suppressed tumor growth in the MIA PaCa-2 tumor cell line, which expressed high levels of HER2/neu. These data suggest that Herceptin treatment of patients with pancreatic cancer who express high levels of the HER2/neu oncogene may be reasonable. Docetaxel, a semisynthetic taxane, has exhibited significant single-agent activity against prostatic tumors. In phase I/II studies, single-agent docetaxel and the combination of docetaxel plus estramustine were effective in inducing prostate-specific antigen reductions of > or =50% in men with androgen-independent prostate cancer (AIPC). The underlying reason for docetaxel's clinical activity against prostate cancer has been a focus of ongoing research. Docetaxel is believed to have a twofold mechanism of antineoplastic activity: (1) inhibition of microtubular depolymerization, and (2) attenuation of the effects of bcl-2 and bcl-xL gene expression. Taxane-induced microtubule stabilization arrests cells in the G(2)M phase of the cell cycle and induces bcl-2 phosphorylation, thereby promoting a cascade of events that ultimately leads to apoptotic cell death. In preclinical studies, docetaxel had a higher affinity for tubulin and was shown to be a more potent inducer of bcl-2 phosphorylation than paclitaxel. Laboratory evidence also supports the clinical evaluation of docetaxel-based combinations that include agents such as trastuzumab and/or estramustine. The pathways for docetaxel-induced apoptosis appear to differ in androgen-dependent and androgen-independent prostate cancer cells. Further elucidation of these differences will be instrumental in designing targeted regimens for the treatment of localized and advanced prostate cancer. The incidence of human epidermal growth factor receptor 2 (HER2) protein overexpression and its prognostic value are not well characterized in patients with prostate cancer. A phase I study was designed to evaluate docetaxel/estramustine plus trastuzumab, a humanized monoclonal antibody that binds to the HER2 receptor, in patients with metastatic androgen-independent prostate cancer (AIPC). HER2 positivity was not required because safety was the primary endpoint. Patients received oral estramustine 280 mg three times daily (days 1 to 5); docetaxel, 70 mg/m(2) intravenously (day 2); and trastuzumab, 2 mg/kg intravenously (days 2, 9, and 19), every 21 days until the disease progressed or toxicity became unacceptable. This regimen was well tolerated among the first 13 treated patients. Grade 4 neutropenia was seen in 10% of administered cycles. There were two episodes of febrile neutropenia and two thrombembolic events. Of the 13 patients evaluable for prostate-specific antigen (PSA) response, nine (69%) experienced a decrease in PSA level of >50%. Two (33%) of six patients with measurable disease had objective responses, and one complete response was seen on bone scan. Docetaxel/estramustine/trastuzumab appears to be a safe combination when used in the treatment of metastatic AIPC. The response data are too preliminary for speculation about the relative benefits of this 3-drug regimen compared with the combination of only docetaxel and estramustine in this clinical setting. BACKGROUND: Overexpression of the HER-2/neu oncoprotein has been reported to occur in </= 60% of patients with prostate carcinoma and to correlate with shortened survival. Trastuzumab is a humanized monoclonal antibody to the HER-2 receptor and has activity against HER-2-positive breast carcinoma, more so when combined with a taxane. The authors screened for HER-2 overexpression in patients developing hormone-refractory prostate carcinoma (HRPC) and conducted a Phase II trial of trastuzumab plus docetaxel in HER-2-positive patients. METHODS: Paraffin-embedded tumor specimens from potentially eligible patients were screened for HER-2 expression by immunohistochemistry (IHC) and/or amplification by fluorescent in situ hybridization (FISH). Shed HER-2 was also assessed by enzyme-linked immunoradsorbent assay (ELISA). Patients with HER-2-positive tumor specimens (IHC 2+ or 3+ or FISH ratio > 2) were initially randomized to receive either single-agent trastuzumab or docetaxel. After two treatment cycles, nonresponding patients received the trastuzumab/docetaxel combination. Treatment was comprised of 30 mg/m(2) of docetaxel weekly for 6 weeks followed by a 2-week break and 4 mg/kg of trastuzumab intravenously during Week 1 then 2 mg/kg per week thereafter. The cycle length was 8 weeks. RESULTS: One hundred patients with HPRC were screened. IHC results were as follows: 3+ (n = 1), 2+ (n = 6), 1+ (n = 26), 0 (n = 39), and insufficient tissue specimen/not tested (n = 28). Only 3 of 37 patients had elevated shed HER-2 by ELISA (> 15 mg/mL). None overexpressed HER-2 by IHC. FISH amplification was found in 0 of 34 tissue samples. Of seven patients with IHC 3+ or 2+, four were tested by ELISA and two by FISH. None were abnormal. Age and Gleason score did not correlate with IHC status. Of the seven patients eligible for the Phase II study, only four agreed to participate. The trial was thus closed for nonfeasibility (the overall HER-2 positivity rate was < 20%). No patient responded to trastuzumab alone. The median survival was not reached and the median progression-free survival was 7 months. CONCLUSIONS: HER-2 overexpression by IHC in archival prostate carcinoma specimens was infrequent. There was no apparent correlation among IHC, ELISA, and FISH, although the sample size was limited. Conclusions regarding the predictive value of HER-2 status on outcome after trastuzumab-based therapy were not reached and were only drawn after larger-scale screening efforts. The authors estimated that 1000 patients need to be screened to complete accrual to a 40-patient efficacy trial. PURPOSE: To investigate the efficacy and toxicity of the antibody to the HER-2/neu receptor (trastuzumab, Herceptin) in the treatment of advanced hormone-refractory prostate cancer (HRPC). MATERIALS AND METHODS: Eighteen patients with HRPC were recruited for this phase II trial in which they received trastuzumab for 12 weeks or until disease progression or unacceptable toxicity was documented. HER-2 receptor overexpression was evaluated using immunohistochemistry (IHC) and dual-color fluorescence in-situ hybridization (FISH) assays. RESULTS: Trastuzumab as a single agent demonstrated little efficacy in treating HRPC. Two patients demonstrated stable disease based on a decrease in PSA level to less than 50% of baseline. No patient demonstrated a regression of radiographic bony or soft tissue metastatic disease. The medication was well tolerated in 16 patients (89%), and 2 patients (11%) had to be hospitalized for cardiac complications. CONCLUSIONS: Trastuzumab (Herceptin) as a single agent demonstrated poor efficacy in treating HRPC. Based on promising results in treating breast cancer with regimens using Herceptin and cytotoxic agents, a similar combination approach might demonstrate better efficacy in treating HRPC. New drugs and new combinations of drugs have recently shown promising clinical activity in hormone refractory prostate cancer. We studied the association of gefitinib with trastuzumab on the androgen-refractory prostate cancer cell line DU145 expressing both epidermal growth factor receptor (EGFR) and HER-2. Drug combinations with radiotherapy (RT) were considered along with the analysis of factors linked to cell proliferation and apoptosis. The antitumour effects of gefitinib were more pronounced than those observed with trastuzumab. In mice receiving the gefitinib-trastuzumab combination, reduction in tumour volume was inferior to that predicted by the observed impact of the agents alone. The presence of trastuzumab markedly attenuated the relative increase on p27 expression and the Bax:Bcl2 ratio induced by gefitinib. The combination gefitinib-RT had similar antitumour effects as those predicted by the impact of the individual treatments, whereas the effect of the trastuzumab-RT combination was inferior to that predicted by the individual effects. The present data should be borne in mind when designing new clinical schedules for treatment of hormone-refractory prostate cancer including the use of HER inhibitors. The human epidermal growth factor receptor (HER) family of receptor tyrosine kinases is part of a network of pathways that are involved in the development and progression of prostate cancer. HER-kinase receptors include epidermal growth factor receptor (EGFR), HER2, HER3, and HER4, which must combine as dimers to affect signaling. Different combinations of receptors produce different qualities and levels of pathway activation. Among HER-family receptors, HER2 activation is particularly important in breast cancer, as HER2 gene amplification is associated with a distinct clinical course and response to treatment with a HER2-directed therapy (trastuzumab). Although HER2 can be over-expressed in prostate cancer, there is no clinical data to support the use of trastuzumab for prostate cancer patients. Preclinical and clinical data show that the activation of the HER-kinase axis is important for the progression of prostate cancer to androgen-independent disease. Data points towards the importance of inhibiting multiple members of the HER-kinase family to achieve more complete blockade of this axis for cancers other than HER2-overexpressing breast cancer. Multiple pharmaceutical agents that block the HER-kinase axis are currently being tested for patients with prostate cancer. These include antibodies, tyrosine kinase inhibitors, and novel strategies which seek to decrease HER2 expression. Present management of metastatic prostate cancer, which includes hormonal therapy, chemotherapy, and radiotherapy, are frequently palliative. Taxanes, and specifically docetaxel, are being extensively investigated to improve the survival of metastatic prostate cancer patients. Although paclitaxel exhibits a wide spectrum of antitumor activity, its therapeutic application is limited, in part, due to its low water solubility that necessitates the use of Cremophor EL, which is known to induce hypersensitivity reactions. Therefore, the objective of this present study was to assess the efficiency of paclitaxel palmitate-loaded anti-HER2 immunoemulsions, a targeted drug delivery system based on cationic emulsion covalently linked to anti-HER2 monoclonal antibody (Herceptin), in a well-established in vivo pharmacologic model of metastatic prostate cancer that overexpresses the HER2 receptor. It was clearly noted that the cationic emulsion and immunoemulsion did not activate the complement compared with the commercial and paclitaxel palmitate hydroalcoholic formulations. In addition, 10 mg/kg of paclitaxel palmitate-loaded immunoemulsion once weekly over 3 weeks inhibits the tumor growth in severe combined immunodeficient mice much more than the cationic emulsion (P < 0.05) and the paclitaxel palmitate formulation (P < 0.01). The histopathologic analysis suggested a therapeutic improvement trend in favor of the immunoemulsion. However, there was no significant difference in antimetastatic activity between the emulsion and the immunoemulsion despite the affinity of the immunoemulsion towards the HER2 receptor. Although the tumor growth was not fully inhibited, the actual results are encouraging and may lead to an improved therapeutic strategy of metastatic prostate cancer treatment. Antitumour activity of docetaxel (Taxotere) in hormone-dependent (HD) and hormone-independent (HID) prostate cancer PAC120 xenograft model was previously reported, and its level was associated with HER2 protein expression. In the present study, we evaluate the antitumour effects of docetaxel combined with trastuzumab (Herceptin), an anti-HER2 antibody. Although trastuzumab alone had no effect on tumour growth, it potentiated the antitumour activity of docetaxel in HD tumours and more strongly in HID variants. Using the HID28 variant, we show that docetaxel treatment of tumour-bearing mice induces an increased HER2 mRNA expression of the tyrosine kinase receptor of 25-fold 24 h after docetaxel treatment, while HER2 protein and p-AKT decreased. This was followed by an increase of HER2 protein 3 days (two-fold) after docetaxel treatment and by a strong HER2 release in the serum of treated mice; expression of phospho-ERK, p27, BCL2 and HSP70 concomitantly increased. Similar molecular alterations were induced by docetaxel plus trastuzumab combination, except for that there was a transient and complete disappearance of AR and HSP90 proteins 24 h after treatment. We show that in addition to its known effects on tubulin and mitotic spindles, docetaxel induces complex signalisation pathway mechanisms in surviving cells, including HER2, which can be pharmacologically targeted. This study suggests that the docetaxel/trastuzumab combination may prove an effective therapeutic approach for HER2-expressing hormone-refractory prostate cancer. BACKGROUND/AIMS: Evaluation of Her2/neu expression in the peripheral blood mononuclear cell fraction of prostate cancer patients by RT-PCR may afford an opportunity for the detection of circulating tumor cells and thus serve as a marker of micrometastatic disease. METHODS: We studied Her2/neu expression by reverse transcriptase-polymerase chain reaction in peripheral blood mononuclear cell fraction samples of 21 controls and serially in 43 patients with prostate cancer. RESULTS: None of the 21 controls expressed Her2/neu whereas 23.25% (95% CI, 11.75-38.63) of the patients were positive at entry into the study, and 65.11% (95% CI, 49.07-78.99) of them had at least one positive result during the follow-up period. Her2/neu positivity at study entry did not correlate significantly with PSA level, Gleason score, clinical stage or time to PSA progression. When we analyzed only patients with advanced disease, we observed a trend towards a shorter time to PSA progression in patients with at least one positive Her2/neu result during the follow-up (log-rank test, P = 0.08). CONCLUSIONS: We conclude that Her2/neu expression in the peripheral blood mononuclear cell fraction of prostate cancer patients is frequent and therefore this assay may potentially be useful to detect the presence of micrometastatic disease in men with prostate cancer and for monitoring patients enrolled in trastuzumab-based therapeutic protocols. The potential of the HER2-targeting antibody trastuzumab as a radioimmunoconjugate useful for both imaging and therapy was investigated. Conjugation of trastuzumab with the acyclic bifunctional chelator CHX-A"-DTPA yielded a chelate:protein ratio of 3.4 ± 0.3; the immunoreactivity of the antibody unaffected. Radiolabeling was efficient, routinely yielding a product with high specific activity. Tumor targeting was evaluated in mice bearing subcutaneous (s.c.) xenografts of colorectal, pancreatic, ovarian, and prostate carcinomas. High uptake of the radioimmunoconjugate, injected intravenously (i.v.), was observed in each of the models, and the highest tumor %ID/g (51.18 ± 13.58) was obtained with the ovarian (SKOV-3) tumor xenograft. Specificity was demonstrated by the absence of uptake of 111In-trastuzumab by melanoma (A375) s.c. xenografts and 111In-HuIgG by s.c. LS-174T xenografts. Minimal uptake of i.v. injected 111In-trastuzumab in normal organs was confirmed in non-tumor-bearing mice. The in vivo behavior of 111In-trastuzumab in mice bearing intraperitoneal (i.p.) LS-174T tumors resulted in a tumor %ID/g of 130.85 ± 273.34 at 24 h. Visualization of tumor, s.c. and i.p. xenografts, was achieved by γ-scintigraphy and PET imaging. Blood pool was evident as expected, but cleared over time. The blood pharmacokinetics of i.v. and i.p. injected 111In-trastuzumab was determined in mice with and without tumors. The data from these in vitro and in vivo studies supported advancement of radiolabeled trastuzumab into two clinical studies, a Phase 0 imaging study in the Molecular Imaging Program of the National Cancer Institute and a Phase 1 radioimmunotherapy study at the University of Alabama. The type I receptor tyrosine kinases (RTKs) are involved in various aspects of cell growth, survival, and differentiation. Among the known RTKs, the epidermal growth factor receptor (EGFR) and ErbB-2 (HER-2) are two widely studied proteins that are prototypic members of the ErbB family which also includes ErbB-3 (Her-3) and ErbB-4 (Her-4). Overexpression of ErbB-2 and EGFR has been associated with aggressive disease and poor patient prognosis in a range of human tumour types (e.g. breast, lung, ovarian, prostate, and squamous carcinoma of head and neck). Disruption of signal transduction of these kinases has been shown to have an antiproliferative effect. Various approaches have been developed to target the ErbB signalling pathways including monoclonal antibodies (trastuzumab/Herceptin™ and cetuximab/Erbitux™) directed against the receptor, and synthetic tyrosine kinase inhibitors (gefitinib/Iressa™ and erlotinib/Tarceva™). Since many tumours overexpress ErbB receptors, simultaneous targeting of multiple ErbB receptors therefore becomes a promising approach to cancer treatment. Lapatinib (Tykerb™), a potent dual EGFR/ErbB-2 inhibitor, was approved for the treatment of ErbB-2-positive breast cancer. Despite years of intensive research on EGFR inhibitors, there is a surprising dearth of chemically distinct small inhibitors with a high degree of selectivity. There is also a need for new scaffolds due to the recent finding of EGFR mutations which render the kinase resistant to gefinitib and erlotinib. The structures under study will be quinazolines with different substituents. The structure-activity relationships and biological evaluation of compounds published during the last four years will be reviewed herein. PURPOSE: Patients with recurrent prostate cancer are commonly treated with androgen withdrawal therapy (AWT); however, almost all patients eventually progress to castration resistant prostate cancer (CRPC), indicating failure of AWT to eliminate androgen-sensitive prostate cancer. The overall goal of these studies is to determine whether dual inhibition of the receptor tyrosine kinases epidermal growth factor receptor (EGFR) and HER2 would prolong the effectiveness of this treatment in prostate cancer. EXPERIMENTAL DESIGN: We used androgen-dependent LNCaP cells and its CRPC sublines LNCaP-AI and C4-2. Additional data were collected in pRNS-1-1 cells stably expressing a mutant androgen receptor (AR-T877A), and in nude mice harboring CWR22 tumors. Studies utilized EGFR inhibitors erlotinib and AG1478, and HER2 inhibitors trastuzumab and AG879. RESULTS: Dual EGFR/HER2 inhibition induced apoptosis selectively in androgen-sensitive prostate cancer cells undergoing AWT, but not in the presence of androgens, or in CRPC cells. We show that AWT alone failed to induce significant apoptosis in androgen-dependent cells, due to AWT-induced increase in HER2 and ErbB3, which promoted survival by increasing Akt phosphorylation. AWT-induced ErbB3 stabilized the AR and stimulated PSA, while it was inactivated only by inhibition of both its dimerization partners EGFR and HER2 (prostate cancer cells do not express ErbB4); but not the inhibition of any one receptor alone, explaining the success of dual EGFR/HER2 inhibition in sensitizing androgen-dependent cells to AWT. The effectiveness of the inhibitors in suppressing growth correlated with its ability to prevent Akt phosphorylation. CONCLUSION: These studies indicate that dual EGFR/HER2 inhibition, administered together with AWT, sensitize prostate cancer cells to apoptosis during AWT. The purpose of this study was to determine therapeutic effects and systemic toxicity of 212Pb-trastuzumab in an orthotopic model of human prostate cancer cells in nude mice. TCMC-Trastuzumab was radiolabeled with 212Pb. The 212Pb-trastuzumab generated from the procedure was intact and had high binding affinity with a dissociation constant (of 3.9±0.99 nM. PC-3MM2 cells, which expressed a lower level of HER2 both in culture and in tumors, were used in therapy studies. A single intravenous injection of 212Pb-trastuzumab reduced tumor growth by 60-80%, reduced aortic lymph node metastasis, and prolonged the survival of tumor-bearing mice. Treatment with 212Pb-trastuzumab did not cause significant changes in body weight, serum glutamic pyruvic transaminase (SGPT), blood urea nitrogen (BUN), hematological profiles, and histological morphology of several major organs of tumor-bearing mice. These findings suggest that a systemic delivery of 212Pb-trastuzumab could be an effective modality for management of advanced human prostate cancer. The treatment of disseminated prostate cancer remains a great challenge in current oncology practice. The proliferation of prostate cancer cells is testosterone-driven, but clonal selection during androgen deprivation therapy promotes the development of androgen-independent (hormone-refractory) cells, which become phenotypically domit. Human epidermal growth factor receptor type 2 (HER2) is capable of activating the androgen receptor pathway, even in the absence of the ligand. The detection of phenotypic changes associated with the development of androgen independence may influence patient management, suggesting the initiation of a second-line therapy. This study aimed to establish the level of HER2 expression in a number of prostate cancer cell lines (LNCaP, PC3 and DU145) in order that they be used as models in further studies, and to evaluate the binding and cellular processing of [(111)In]-labeled trastuzumab and the anti-HER2 synthetic Affibody molecule ABY-025 in these cell lines. The expression of HER2 was demonstrated and quantified in all three tested prostate cancer cell-lines. Studies on cellular processing demonstrated that internalization of both conjugates increased continuously during the whole incubation. The internalization rate was approximately equal for both monoclonal antibodies and Affibody molecules. In both cases, internalization was moderately rapid. Such features would definitely favor the use of radiometal labels for trastuzumab and, most likely, for affibody molecules. The level of HER2 expression in these cell lines is sufficient for in vivo molecular imaging. The epidermal growth factor receptor (EGFR) family members are potential targets for therapy using extra-cellular domain receptor binding agents, such as the antibodies trastuzumab and cetuximab, or antibodies labeled with therapeutically useful radionuclides or toxins. This is especially the case when the tumor cells are resistant to chemotherapy and tyrosine kinase inhibitors. Studies concerning the expression of these receptors in prostate cancer vary in the literature, possibly due to differences in patient inclusion, sample preparations and scoring criteria. In our study, EGFR, HER2 and HER3 expression was analyzed in prostate cancer samples from primary tumors and corresponding lymph node metastases from 12 patients. The expression of HER2 and EGFR was scored from immunohistochemical preparations and the HercepTest criteria (0, 1+, 2+ or 3+), while HER3 expression was scored as no, weak or strong staining. There were 5 EGFR-positive (2+ or 3+) primary tumors and 6 EGFR-positive lymph node metastases, and there was EGFR upregulation in one metastasis. Only 4 of the 12 patients had marked HER2 expression (2+ or 3+) in their primary tumors and there was one downregulation and 5 cases of upregulation in the metastases. Thus, a total of 8 out of 12 analyzed metastases were HER2-positive. Of the 12 primary tumors, 9 expressed HER3 while only 2 of the lymph node metastases expressed recognizable HER3 staining, so 7 metastases appeared to have downregulated HER3 expression. In one of the primary tumors there was positive co-expression of EGFR and HER2, while this co-expression was observed in 4 of the metastases. Thus, there were tendencies for upregulation of HER2, increased co-expression of EGFR and HER2 and downregulation of HER3 in the prostate cancer lymph node metastases in comparison to the primary tumors. The results are encouraging for studies involving more patients. Possible strategies for EGFR- and HER2-targeted therapy are briefly discussed in the present study, especially with regard to the expression and co-expression of EGFR and HER2 in metastases.
Which are the Yamanaka factors?
The Yamanaka factors are the OCT4, SOX2, MYC, and KLF4 transcription factors
Yamanaka factors (Oct3/4, Sox2, Klf4, c-Myc) are highly expressed in embryonic stem (ES) cells, and their over-expression can induce pluripotency in both mouse and human somatic cells, indicating that these factors regulate the developmental signaling network necessary for ES cell pluripotency. However, systemic analysis of the signaling pathways regulated by Yamanaka factors has not yet been fully described. In this study, we identified the target promoters of endogenous Yamanaka factors on a whole genome scale using ChIP (chromatin immunoprecipitation)-on-chip in E14.1 mouse ES cells, and we found that these four factors co-occupied 58 promoters. Interestingly, when Oct4 and Sox2 were analyzed as core factors, Klf4 functioned to enhance the core factors for development regulation, whereas c-Myc seemed to play a distinct role in regulating metabolism. The pathway analysis revealed that Yamanaka factors collectively regulate a developmental signaling network composed of 16 developmental signaling pathways, nine of which represent earlier unknown pathways in ES cells, including apoptosis and cell-cycle pathways. We further analyzed data from a recent study examining Yamanaka factors in mouse ES cells. Interestingly, this analysis also revealed 16 developmental signaling pathways, of which 14 pathways overlap with the ones revealed by this study, despite that the target genes and the signaling pathways regulated by each individual Yamanaka factor differ significantly between these two datasets. We suggest that Yamanaka factors critically regulate a developmental signaling network composed of approximately a dozen crucial developmental signaling pathways to maintain the pluripotency of ES cells and probably also to induce pluripotent stem cells. Ectopic expression of key reprogramming transgenes in somatic cells enables them to adopt the characteristics of pluripotency. Such cells have been termed induced pluripotent stem (iPS) cells and have revolutionized the field of somatic cell reprogramming, as the need for embryonic material is obviated. One of the issues facing both the clinical translation of iPS cell technology and the efficient derivation of iPS cell lines in the research laboratory is choosing the most appropriate somatic cell type for induction. In this study, we demonstrate the direct reprogramming of a defined population of neural stem cells (NSCs) derived from the subventricular zone (SVZ) and adipose tissue-derived cells (ADCs) from adult mice using retroviral transduction of the Yamanaka factors Oct4, Sox2, Klf4, and c-Myc, and compared the results obtained with a mouse embryonic fibroblast (mEF) control. We isolated mEFs, NSCs, and ADCs from transgenic mice, which possess a GFP transgene under control of the Oct4 promoter, and validated GFP expression as an indicator of reprogramming. While transduction efficiencies were not significantly different among the different cell types (mEFs 68.70 +/- 2.62%, ADCs 70.61 +/- 15.4%, NSCs, 68.72 +/- 3%, p = 0.97), the number of GFP-positive colonies and hence the number of reprogramming events was significantly higher for both NSCs (13.50 +/- 4.10 colonies, 0.13 +/- 0.06%) and ADCs (118.20 +/- 38.28 colonies, 1.14 +/- 0.77%) when compared with the mEF control (3.17 +/- 0.29 colonies, 0.03 +/- 0.005%). ADCs were most amenable to reprogramming with an 8- and 38-fold greater reprogramming efficiency than NSCs and mEFs, respectively. Both NSC iPS and ADC iPS cells were demonstrated to express markers of pluripotency and could differentiate to the three germ layers, both in vitro and in vivo, to cells representative of the three germ lineages. Our findings confirm that ADCs are an ideal candidate as a readily accessible somatic cell type for high efficiency establishment of iPS cell lines. Epidermal melanocytes play an important role in protecting the skin from UV rays, and their functional impairment results in pigment disorders. Additionally, melanomas are considered to arise from mutations that accumulate in melanocyte stem cells. The mechanisms underlying melanocyte differentiation and the defining characteristics of melanocyte stem cells in humans are, however, largely unknown. In the present study, we set out to generate melanocytes from human iPS cells in vitro, leading to a preliminary investigation of the mechanisms of human melanocyte differentiation. We generated iPS cell lines from human dermal fibroblasts using the Yamanaka factors (SOX2, OCT3/4, and KLF4, with or without c-MYC). These iPS cell lines were subsequently used to form embryoid bodies (EBs) and then differentiated into melanocytes via culture supplementation with Wnt3a, SCF, and ET-3. Seven weeks after inducing differentiation, pigmented cells expressing melanocyte markers such as MITF, tyrosinase, SILV, and TYRP1, were detected. Melanosomes were identified in these pigmented cells by electron microscopy, and global gene expression profiling of the pigmented cells showed a high similarity to that of human primary foreskin-derived melanocytes, suggesting the successful generation of melanocytes from iPS cells. This in vitro differentiation system should prove useful for understanding human melanocyte biology and revealing the mechanism of various pigment cell disorders, including melanoma. Generation of induced pluripotent stem (iPS) cells from somatic cells has been successfully achieved by ectopic expression of four transcription factors, Oct4, Sox2, Klf4 and c-Myc, also known as the Yamanaka factors. In practice, initial iPS colonies are picked based on their embryonic stem (ES) cell-like morphology, but often may go on to fail subsequent assays, such as the alkaline phosphate (AP) assay. In this study, we co-expressed through lenti-viral delivery the Yamanaka factors in amniotic fluid-derived (AF) cells. ES-like colonies were picked onto a traditional feeder layer and a high percentage AF-iPS with partial to no AP activity was found. Interestingly, we obtained an overwhelming majority of fully stained AP positive (AP+) AF-iPS colonies when colonies were first seeded on a feeder-free culture system, and then transferred to a feeder layer for expansion. Furthermore, colonies with no AP activity were not detected. This screening step decreased the variation seen between morphology and AP assay. We observed the AF-iPS colonies grown on the feeder layer with 28% AP+ colonies, 45% AP partially positive (AP+/-) colonies and 27% AP negative (AP-) colonies, while colonies screened by the feeder-free system were 84% AP+ colonies, 16% AP+/- colonies and no AP- colonies. The feeder-free screened AP+ AF-iPS colonies were also positive for pluripotent markers, OCT4, SOX2, NANOG, TRA-1-60, TRA-1-81, SSEA-3 and SSEA-4 as well as having differentiation abilities into three germ layers in vitro and in vivo. In this study, we report a simplistic, one-step method for selection of AP+ AF-iPS cells via feeder-free screening. Induced pluripotent stem (iPS) cells can be obtained from terminally differentiated somatic cells by overexpression of defined sets of reprogramming transcription factors. These protein sets have been called the Yamanaka factors, namely Sox2, Oct3/4 (Pou5f1), Klf4, and c-Myc, and the Thomson factors, namely Sox2, Oct3, Lin28, and Nanog. Other sets of proteins, while not essential for the formation of iPS cells, are important for improving the efficiency of the induction and still other sets of proteins are important as markers for embryonic stem cells. Structural information about most of these important proteins is very sparse. Our bioinformatics analysis herein reveals that these reprogramming factors and most of the efficiency-improving and embryonic stem cell markers are highly enriched in intrinsic disorder. As is typical for transcription factors, these proteins are modular. Specific sites for interaction with other proteins and DNA are dispersed in the long regions of intrinsic disorder. These highly dynamic interaction sites are evidently responsible for the delicate interplay among various molecules. The bioinformatics analysis given herein should facilitate the investigation of the roles and organization of these modular interaction sites, thereby helping to shed further light on the pathways that underlie the mechanism(s) by which terminally differentiated cells are converted to iPS cells. Human induced pluripotent stem cells (iPSCs) have become an intriguing approach for neurological disease modeling, because neural lineage-specific cell types that retain the donors' complex genetics can be established in vitro. The statistical power of these iPSC-based models, however, is dependent on accurate diagnoses of the somatic cell donors; unfortunately, many neurodegenerative diseases are commonly misdiagnosed in live human subjects. Postmortem histopathological examination of a donor's brain, combined with premortem clinical criteria, is often the most robust approach to correctly classify an individual as a disease-specific case or unaffected control. In this study, we describe iPSCs generated from a skin biopsy collected postmortem during the rapid autopsy of a 75-year-old male, whole body donor, defined as an unaffected neurological control by both clinical and histopathological criteria. These iPSCs were established in a feeder-free system by lentiviral transduction of the Yamanaka factors, Oct3/4, Sox2, Klf4, and c-Myc. Selected iPSC clones expressed both nuclear and surface antigens recognized as pluripotency markers of human embryonic stem cells (hESCs) and were able to differentiate in vitro into neurons and glia. Statistical analysis also demonstrated that fibroblast proliferation was significantly affected by biopsy site, but not donor age (within an elderly cohort). These results provide evidence that autopsy donor-derived fibroblasts can be successfully reprogrammed into iPSCs, and may provide an advantageous approach for generating iPSC-based neurological disease models. Induced pluripotent stem (iPS) cells have the potential to become a universal resource for cell-based therapies in regenerative medicine; however, prior to the use of such iPS cell-based therapies, preclinical assessment of their safety and efficacy is essential. Non-human primates serve as valuable animal models for human diseases or biomedical research; therefore, in this study, we generated cynomolgus monkey iPS cells from adult skin and fetal fibroblast cells by the retrovirally mediated introduction of four human transcription factors: c-Myc, Klf4, Oct3/4, and Sox2 (the so-called "Yamanaka factors"). Twenty to 30 days after the introduction of these factors, several cynomolgus monkey embryonic stem (ES) cell-like colonies appeared on SNL and mouse embryonic fibroblast (MEF) feeder layers. These colonies were picked and cultivated in primate ES medium. Seven iPS cell lines were established, and we detected the expression of pluripotent markers that are also expressed in ES cells. Reverse transcription polymerase chain reaction (PCR) showed that these iPS cells expressed endogenous c-Myc, Klf4, Oct3/4, and Sox2 genes, whereas several transgenes were silenced. Embryoid body and teratoma formation showed that the cynomolgus iPS cells had the developmental potential to differentiate into cells of all three primary germ layers. In summary, we generated cynomolgus monkey iPS cells by retrovirus-mediated transduction of the human transcription factors, c-Myc, Klf4, Oct3/4, and Sox2 into adult cynomolgus monkey skin cells and fetal fibroblasts. The cynomolgus monkey is the most relevant primate model for human disease, and the highly efficient generation of monkey iPS cells would allow investigation of the treatments of various diseases in this model via therapeutic cloning. Germ cell tumors (GCTs) are unique in that they exhibit diverse biological characteristics and pathological features. Although several in vivo GCT models are available, studies on GCTs are hampered because in vivo development of GCTs is time consuming and prevents a detailed molecular analysis of the transformation process. Here we developed a novel strategy to transform mouse testis cells in vitro. Lentivirus-mediated transfection of domit negative Trp53, Myc, and activated Hras1 into a CD9-expressing testis cells caused tumorigenic conversion in vitro. Although these cells resembled embryonic stem (ES) cells, they were aneuploid and lacked Nanog expression, which is involved in the maintece of the undifferentiated state in ES cells. Euploid ES-like cells were produced by transfecting the Yamanaka factors (Pou5f1, Myc, Klf4, and Sox2) into the same cell population. Although these cells expressed Nanog, they were distinct from ES cells in that they expressed CD44, a cancer stem cell antigen. Both treatments induced similar changes in the DNA methylation patterns in differentially methylated regions of imprinted genes. Moreover, despite the differences in their phenotype and karyotype, both cell types similarly produced mixed GCTs on transplantation, which were composed of teratomas, seminomas, and embryonal carcinomas. Thus, in vitro testis cell transformation facilitates an analysis of the GCT formation process, and our results also suggest the close similarity between GCT formation and reprogramming. BACKGROUND: Recent studies have found that p53 and its' associated cell cycle pathways are major inhibitors of human induced pluripotent stem (iPS) cell generation. In the same family as p53 is p73, which shares sequence similarities with p53. However, p73 also has distinct properties of its own, such as two alternative promoters to express transactivation of p73 (TAp73) and N terminal deleted p73 (DNp73). Functionally, TAp73 acts similarly to p53 in tumor suppression. However, DNp73, on the other hand acts as an oncogene to suppress p53 and p73 induced apoptosis. Therefore, how can p73 have opposing roles in human iPS cell generation? RESULTS: Transcription factors, Oct4, Sox2, Klf4 and cMyc (4TF, Yamanaka factors) are used as basal conditions to generate iPS cells. In addition, the factor of DNp73(actually alpha splicing DNp73, DNp73α) is used to generate iPS cells. The experiment found that the addition of DNp73 gene increases human iPS cell generation efficiency by 12.6 folds in comparison to human fibroblast cells transduced with only the basal conditions. Also, iPS cells generated with DNp73 expression are more resistant to in vitro and in vivo differentiation. CONCLUSIONS: This study found DNp73, a family member of p53, is also involved in the human iPS cell generation. Specifically, that the involvement of DNp73 generates iPS cells that are more resistant to in vitro and in vivo differentiation. Therefore, this data may prove to be useful in future developmental studies and cancer researches. Induced pluripotent stem (iPS) cells were originally generated from mouse fibroblasts by enforced expression of Yamanaka factors (Oct3/4, Sox2, Klf4, and c-Myc). The technique was quickly reproduced with human fibroblasts or mesenchymal stem cells. Although having been showed therapeutic potential in animal models of sickle cell anemia and Parkinson's disease, iPS cells generated by viral methods do not suit all the clinical applications. Various non-viral methods have appeared in recent years for application of iPS cells in cell transplantation therapy. These methods mainly include DNA vector-based approaches, transfection of mRNA, and transduction of reprogramming proteins. This review summarized these non-viral methods and compare the advantages, disadvantages, efficiency, and safety of these methods. Signal transducer and activator of transcription (STAT) 3, a member of a family of DNA-binding molecules, is a potential target in the treatment of cancer. The highly phosphorylated STAT3 in cancer cells contributes to numerous physiological and oncogenic signaling pathways. Furthermore, a significant association between STAT3 signaling and glioblastoma multiforme stem-like cell (GBM-SC) development and maintece has been demonstrated in recent studies. Previously, we reported a novel small molecule inhibitor of STAT3 dimerization, STX-0119, as a cancer therapeutic. In the present study, we focused on cancer stem-like cells derived from recurrent GBM patients and investigated the efficacy of STX-0119. Three GBM stem cell lines showed many stem cell markers such as CD133, EGFR, Nanog, Olig2, nestin and Yamanaka factors (c-myc, KLF4, Oct3/4 and SOX2) compared with parental cell lines. These cell lines also formed tumors in vivo and had similar histological to surgically resected tumors. STAT3 phosphorylation was activated more in the GBM-SC lines than serum-derived GB cell lines. The growth inhibitory effect of STX-0119 on GBM-SCs was moderate (IC50 15-44 µM) and stronger compared to that of WP1066 in two cell lines. On the other hand, the effect of temozolomide was weak in all the cell lines (IC50 53-226 µM). Notably, STX-0119 demonstrated strong inhibition of the expression of STAT3 target genes (c-myc, survivin, cyclin D1, HIF-1α and VEGF) and stem cell-associated genes (CD44, Nanog, nestin and CD133) as well as the induction of apoptosis in one stem-like cell line. Interestingly, VEGFR2 mRNA was also remarkably inhibited by STX-0119. In a model using transplantable stem-like cell lines in vivo GB-SCC010 and 026, STX-0119 inhibited the growth of GBM-SCs at 80 mg/kg. STX-0119, an inhibitor of STAT3, may serve as a novel therapeutic compound against GBM-SCs even in temozolomide-resistant GBM patients and has the potential for GBM-SC-specific therapeutics in combination with temozolomide plus radiation therapy. CytoTune™-iPS Reprogramming System uses vectors based on replication in competent Sendai virus (SeV) to safely and effectively deliver and express key genetic factors necessary for reprogramming somatic cells into iPSCs. In contrast to many available protocols, which rely on viral vectors that integrate into the genome of the host cell, the CytoTune™ Reprogramming System uses vectors that are non-integrating and remain in the cytoplasm (i.e., they are zero-footprint). In addition, the host cell can be cleared of the vectors and reprogramming factor genes by exploiting the cytoplasmic nature of SeV and the functional temperature sensitivity mutations introduced into the key viral proteins. The CytoTune™-iPS Reprogramming Kit contains four SeV-based reprogramming vectors, each capable of expressing one of the four Yamanaka factors (i.e., Oct4, Sox2, Klf4, and c-Myc) and are optimized for generating iPSCs from human somatic cells. The reprogramming vectors in this kit have been engineered to increase biological and environmental safety. The recently established reprogramming of somatic cells into induced pluripotent stem cells (iPSCs) by Takahashi and Yamanaka represents a valuable tool for future therapeutic applications. To date, the mechanisms underlying this process are still largely unknown. In particular, the mechanisms how the Yamanaka factors (Oct4, Sox2, Klf4, and c-Myc) directly drive reprogramming and which additional components are involved are still not yet understood. In this study, we aimed at analyzing the role of ADP-ribosyltransferase diphtheria toxin-like one (Artd1; formerly called poly(ADP-ribose) polymerase 1 [Parp1]) during reprogramming. We found that poly(ADP-ribosylation) (PARylation) of the reprogramming factor Sox2 by Artd1 plays an important role during the first days upon transduction with the reprogramming factors. A process that happens before Artd1 in conjunction with 10-11 translocation-2 (Tet2) mediates the histone modifications necessary for the establishment of an activated chromatin state at pluripotency loci (e.g., Nanog and Essrb) [Nature 2012;488:652-655]. Wild-type (WT) fibroblasts treated with an Artd1 inhibitor as well as fibroblasts deficient for Artd1 (Artd1-/-) show strongly decreased reprogramming capacity. Our data indicate that Artd1-mediated PARylation of Sox2 favors its binding to the fibroblast growth factor 4 (Fgf4) enhancer, thereby activating Fgf4 expression. The importance of Fgf4 during the first 4 days upon initiation of reprogramming was also highlighted by the observation that exogenous addition of Fgf4 was sufficient to restore the reprogramming capacity of Artd1-/- fibroblast to WT levels. In conclusion, our data clearly show that the interaction between Artd1 and Sox2 is crucial for the first steps of the reprogramming process and that early expression of Fgf4 (day 2 to day 4) is an essential component for the successful generation of iPSCs. The 'Yamanaka factors' (Oct4, Sox2, Klf4 and c-Myc) are able to generate induced pluripotent stem (iPS) cells from different cell types. However, to what degree primary maligt cells can be reprogrammed into a pluripotent state has not been vigorously assessed. We established an acute myeloid leukemia (AML) model by overexpressing the human mixed-lineage leukemia-AF9 (MLL-AF9) fusion gene in mouse hematopoietic cells that carry Yamanaka factors under the control of doxycycline (Dox). On addition of Dox to the culture, the transplantable leukemia cells were efficiently converted into iPS cells that could form teratomas and produce chimeras. Interestingly, most chimeric mice spontaneously developed the same type of AML. Moreover, both iPS reprogramming and leukemia reinitiation paths could descend from the same leukemia-initiating cell. RNA-seq analysis showed reversible global gene expression patterns between these interchangeable leukemia and iPS cells on activation or reactivation of MLL-AF9, suggesting a sufficient epigenetic force in driving the leukemogenic process. This study represents an important step for further defining the potential interplay between oncogenic molecules and reprogramming factors during MLL leukemogenesis. More importantly, our reprogramming approach may be expanded to characterize a range of hematopoietic maligcies in order to develop new strategies for clinical diagnosis and treatment.
What is the aim of the Human Chromosome-centric Proteome Project (C-HPP)?
The chromosome-centric human proteome project aims to systematically map all human proteins, chromosome by chromosome, in a gene-centric manner through dedicated efforts from national and international teams
The objective of the international Chromosome-Centric Human Proteome Project (C-HPP) is to map and annotate all proteins encoded by the genes on each human chromosome. The C-HPP consortium was established to organize a collaborative network among the research teams responsible for protein mapping of individual chromosomes and to identify compelling biological and genetic mechanisms influencing colocated genes and their protein products. The C-HPP aims to foster the development of proteome analysis and integration of the findings from related molecular -omics technology platforms through collaborations among universities, industries, and private research groups. The C-HPP consortium leadership has elicited broad input for standard guidelines to manage these international efforts more efficiently by mobilizing existing resources and collaborative networks. The C-HPP guidelines set out the collaborative consensus of the C-HPP teams, introduce topics associated with experimental approaches, data production, quality control, treatment, and transparency of data, goverce of the consortium, and collaborative benefits. A companion approach for the Biology and Disease-Driven HPP (B/D-HPP) component of the Human Proteome Project is currently being organized, building upon the Human Proteome Organization's organ-based and biofluid-based initiatives (www.hupo.org/research). The common application of these guidelines in the participating laboratories is expected to facilitate the goal of a comprehensive analysis of the human proteome. The goal of the Human Proteome Project (HPP) is to fully characterize the 21,000 human protein-coding genes with respect to the estimated two million proteins they encode. As such, the HPP aims to create a comprehensive, detailed resource to help elucidate protein functions and to advance medical treatment. Similarly to the Human Genome Project (HGP), the HPP chose a chromosome-centric approach, assigning different chromosomes to different countries. Here we introduce a scoring method for chromosome ranking based on several characteristics, including relevance to health problems, existing published knowledge, and current transcriptome and proteome coverage. The score of each chromosome was computed as a weighted combination of indexes reflecting the aforementioned characteristics. The approach is tailored to the chromosome-centric HPP (C-HPP), and is advantageous in that it takes into account currently available information. We ranked the human chromosomes using the proposed score, and observed that Chr Y, Chr 13, and Chr 18 were top-ranked, whereas the scores of Chr 19, Chr 11, and Chr 17 were comparatively low. For Chr 18, selected for the Russian part of C-HPP, about 25% of the encoded genes were associated with diseases, including cancers and neurodegenerative and psychiatric diseases, as well as type 1 diabetes and essential hypertension. This ranking approach could easily be adapted to prioritize research for other sets of genes, such as metabolic pathways and functional categories. The Chromosome-centric Human Proteome Project (C-HPP) aims to define all proteins encoded in each chromosome and especially to identify proteins that currently lack evidence by mass spectrometry. The C-HPP also prioritizes particular protein subsets such as membrane proteins, post-translational modifications, and low-abundance proteins. In this study, we aimed to generate deep profiling of the membrane proteins of human breast cancer tissues on a chromosome-by-chromosome basis using shotgun proteomics. We identified 7092 unique proteins using membrane fractions isolated from pooled breast cancer tissues with high confidence. A total of 3282 proteins were annotated as membrane proteins by Gene Ontology analysis, which covered 45% of the membrane proteins predicted in 20,859 protein-coding genes. Furthermore, we were able to identify 851 membrane proteins that currently lack evidence by mass spectrometry in neXtProt. Our results will contribute to the accomplishment of the primary goal of the C-HPP in identifying so-called "missing proteins" and generating a whole protein catalog for each chromosome. About 5000 (25%) of the ~20400 human protein-coding genes currently lack any experimental evidence at the protein level. For many others, there is only little information relative to their abundance, distribution, subcellular localization, interactions, or cellular functions. The aim of the HUPO Human Proteome Project (HPP, www.thehpp.org ) is to collect this information for every human protein. HPP is based on three major pillars: mass spectrometry (MS), antibody/affinity capture reagents (Ab), and bioinformatics-driven knowledge base (KB). To meet this objective, the Chromosome-Centric Human Proteome Project (C-HPP) proposes to build this catalog chromosome-by-chromosome ( www.c-hpp.org ) by focusing primarily on proteins that currently lack MS evidence or Ab detection. These are termed "missing proteins" by the HPP consortium. The lack of observation of a protein can be due to various factors including incorrect and incomplete gene annotation, low or restricted expression, or instability. neXtProt ( www.nextprot.org ) is a new web-based knowledge platform specific for human proteins that aims to complement UniProtKB/Swiss-Prot ( www.uniprot.org ) with detailed information obtained from carefully selected high-throughput experiments on genomic variation, post-translational modifications, as well as protein expression in tissues and cells. This article describes how neXtProt contributes to prioritize C-HPP efforts and integrates C-HPP results with other research efforts to create a complete human proteome catalog. MALDI imaging mass spectrometry is a powerful tool for morphology-based proteomic tissue analysis. However, peptide identification is still a major challenge due to low S/N ratios, low mass accuracy and difficulties in correlating observed m/z species with peptide identities. To address this, we have analyzed tryptic digests of formalin-fixed paraffin-embedded tissue microarray cores, from 31 ovarian cancer patients, by LC-MS/MS. The sample preparation closely resembled the MALDI imaging workflow in order to create representative reference data sets containing peptides also observable in MALDI imaging experiments. This resulted in 3844 distinct peptide sequences, at a false discovery rate of 1%, for the entire cohort and an average of 982 distinct peptide sequences per sample. From this, a total of 840 proteins and, on average, 297 proteins per sample could be inferred. To support the efforts of the Chromosome-centric Human Proteome Project Consortium, we have annotated these proteins with their respective chromosome location. In the presented work, the benefit of using a large cohort of data sets was exemplified by correct identification of several m/z species observed in a MALDI imaging experiment. The tryptic peptide data sets generated will facilitate peptide identification in future MALDI imaging studies on ovarian cancer. One of the major challenges of a chromosome-centric proteome project is to explore in a systematic manner the potential proteins identified from the chromosomal genome sequence, but not yet characterized on a protein level. Here, we describe the use of RNA deep sequencing to screen human cell lines for RNA profiles and to use this information to select cell lines suitable for characterization of the corresponding gene product. In this manner, the subcellular localization of proteins can be analyzed systematically using antibody-based confocal microscopy. We demonstrate the usefulness of selecting cell lines with high expression levels of RNA transcripts to increase the likelihood of high quality immunofluorescence staining and subsequent successful subcellular localization of the corresponding protein. The results show a path to combine transcriptomics with affinity proteomics to characterize the proteins in a gene- or chromosome-centric manner. The Chromosome 16 Consortium forms part of the Human Proteome Project that aims to develop an entire map of the proteins encoded by the human genome following a chromosome-centric strategy (C-HPP) to make progress in the understanding of human biology in health and disease (B/D-HPP). A Spanish consortium of 16 laboratories was organized into five working groups: Protein/Antibody microarrays, protein expression and Peptide Standard, S/MRM, Protein Sequencing, Bioinformatics and Clinical healthcare, and Biobanking. The project is conceived on a multicenter configuration, assuming the standards and integration procedures already available in ProteoRed-ISCIII, which is encompassed within HUPO initiatives. The products of the 870 protein coding genes in chromosome 16 were analyzed in Jurkat T lymphocyte cells, MCF-7 epithelial cells, and the CCD18 fibroblast cell line as it is theoretically expected that most chromosome 16 protein coding genes are expressed in at least one of these. The transcriptome and proteome of these cell lines was studied using gene expression microarray and shotgun proteomics approaches, indicating an ample coverage of chromosome 16. With regard to the B/D section, the main research areas have been adopted and a biobanking initiative has been designed to optimize methods for sample collection, management, and storage under normalized conditions and to define QC standards. The general strategy of the Chr-16 HPP and the current state of the different initiatives are discussed. A first research development progress report of the Chromosome 19 Consortium with members from Sweden, Norway, Spain, United States, China and India, a part of the Chromosome-centric Human Proteome Project (C-HPP) global initiative, is presented ( http://www.c-hpp.org ). From the chromosome 19 peptide-targeted library constituting 6159 peptides, a pilot study was conducted using a subset with 125 isotope-labeled peptides. We applied an annotation strategy with triple quadrupole, ESI-Qtrap, and MALDI mass spectrometry platforms, comparing the quality of data within and in between these instrumental set-ups. LC-MS conditions were outlined by multiplex assay developments, followed by MRM assay developments. SRM was applied to biobank samples, quantifying kallikrein 3 (prostate specific antigen) in plasma from prostate cancer patients. The antibody production has been initiated for more than 1200 genes from the entire chromosome 19, and the progress developments are presented. We developed a dedicated transcript microarray to serve as the mRNA identifier by screening cancer cell lines. NAPPA protein arrays were built to align with the transcript data with the Chromosome 19 NAPPA chip, dedicated to 90 proteins, as the first development delivery. We have introduced an IT-infrastructure utilizing a LIMS system that serves as the key interface for the research teams to share and explore data generated within the project. The cross-site data repository will form the basis for sample processing, including biological samples as well as patient samples from national Biobanks. In an effort to map the human proteome, the Chromosome-centric Human Proteome Project (C-HPP) was recently initiated. As a member of the international consortium working on this project, our laboratory developed a gene-centric proteomic database called GenomewidePDB, which integrates proteomic data for proteins encoded by chromosomes with transcriptomic data and other information from public databases. As an example case, we chose chromosome 13, which is the largest acrocentric human chromosome with the lowest gene density and contains 326 predicted proteins. All proteins stored in GenomewidePDB are linked to other resources, including neXtProt and Ensembl for protein and gene information, respectively. The Global Proteome Machine database (GPMdb) and the PeptideAtlas are also accessed for observed mass spectrometry (MS) information, while Human Protein Atlas is used for information regarding antibody availability and tissue expression, respectively. Gene ontology disease information is also included. As a pilot work, we constructed this GenomewidePDB with the identified 3615 proteins including 53 chromosome 13-origin proteins that are present in normal human placenta tissue. Thus, developing a comprehensive database containing actual experimental proteomics data will provide a valuable resource for cross chromosomal comparison in the C-HPP community. The Chromosome-centric Human Proteome Project (C-HPP) aims to systematically map the entire human proteome with the intent to enhance our understanding of human biology at the cellular level. This project attempts simultaneously to establish a sound basis for the development of diagnostic, prognostic, therapeutic, and preventive medical applications. In Iran, current efforts focus on mapping the proteome of the human Y chromosome. The male-specific region of the Y chromosome (MSY) is unique in many aspects and comprises 95% of the chromosome's length. The MSY continually retains its haploid state and is full of repeated sequences. It is responsible for important biological roles such as sex determination and male fertility. Here, we present the most recent update of MSY protein-encoding genes and their association with various traits and diseases including sex determination and reversal, spermatogenesis and male infertility, cancers such as prostate cancers, sex-specific effects on the brain and behavior, and graft-versus-host disease. We also present information available from RNA sequencing, protein-protein interaction, post-translational modification of MSY protein-coding genes and their implications in biological systems. An overview of Human Y chromosome Proteome Project is presented and a systematic approach is suggested to ensure that at least one of each predicted protein-coding gene's major representative proteins will be characterized in the context of its major anatomical sites of expression, its abundance, and its functional relevance in a biological and/or medical context. There are many technical and biological issues that will need to be overcome in order to accomplish the full scale mapping. The grand vision of the human proteome project (HPP) is moving closer to reality with the recent announcement by HUPO of the creation of the HPP consortium in charge of the development of a two-part HPP, one focused on the description of proteomes of biological samples or related to diseases (B/D-HPP) and the other dedicated to a systematic description of proteins as gene products encoded in the human genome (the C-HPP). This new initiative of HUPO seeks to identify and characterize at least one representative protein from every gene, create a protein distribution atlas and a protein pathway or network map. This vision for proteomics can be the roadmap of biological and clinical research for years to come if it delivers on its promises. The Industrial Advisory Board (IAB) to HUPO shares the visions of C-HPP. The IAB will support and critically accompany the overall project goals and the definitions of the critical milestones. The member companies are in a unique position to develop hardware and software, reagents and standards, procedures, and workflows to ensure a reliable source of tools available to the proteomics community worldwide. In collaboration with academia, the IAB member companies can and must develop the tools to reach the ambitious project goals. We offer to partner with and challenge the academic groups leading the C-HPP to define both ambitious and obtainable goals and milestones to make the C-HPP a real and trusted resource for future biology. A gene-centric Human Proteome Project has been proposed to characterize the human protein-coding genes in a chromosome-centered manner to understand human biology and disease. Here, we report on the protein evidence for all genes predicted from the genome sequence based on manual annotation from literature (UniProt), antibody-based profiling in cells, tissues and organs and analysis of the transcript profiles using next generation sequencing in human cell lines of different origins. We estimate that there is good evidence for protein existence for 69% (n = 13985) of the human protein-coding genes, while 23% have only evidence on the RNA level and 7% still lack experimental evidence. Analysis of the expression patterns shows few tissue-specific proteins and approximately half of the genes expressed in all the analyzed cells. The status for each gene with regards to protein evidence is visualized in a chromosome-centric manner as part of a new version of the Human Protein Atlas ( www.proteinatlas.org ).
Where is the protein Pannexin1 located?
The protein Pannexin1 is localized to the plasma membranes.
Our previously reported cDNA array datasets from neonatal wild-type and Cx43-/- (approved gene symbol Gja1) mouse brains were further analyzed to identify underlying interlinkages in the brain transcriptome. The analysis revealed that no gene cohort sharing either primary function or chromosomal location was significantly altered (up-and down-regulation were roughly balanced) in Cx43-/- brains, but each cohort exhibited significant perturbation of transcript abundance proportions and reduced expression variability and coordination. By comparing pairwise expression correlations of all genes with one another in wild-type brains, we found genes exhibiting remarkable similarity or opposition to the coordination profile (set of synergistically, antagonistically, and independently expressed partners) of Cx43, one of the most similar being pannexin1, a vertebrate homolog of invertebrate gap junction proteins. This study indicates striking redundancy of expression controls over functional pathways and suggests that certain genes may play roles similar to or opposite that of Cx43 in organizing the brain transcriptome. In the retina, chemical and electrical synapses couple neurons into functional networks. New candidates encoding for electrical synapse proteins have recently emerged. In the present study, we determined the localization of the candidate protein pannexin1 (zfPanx1) in the zebrafish retina and studied the functional properties of zfPanx1 exogenously expressed in Neuroblastoma 2a (N2a) cells. zfPanx1 was identified on the surface of horizontal cell dendrites invaginating deeply into the cone pedicle near the glutamate release sites of the cones, providing in vivo evidence for hemichannel formation at that location. This strategic position of zfPanx1 in the photoreceptor synapse could potentially allow modulation of cone output. Using whole cell voltage clamp and excised patch recordings of transfected N2a cells, we demonstrated that zfPanx1 forms voltage-activated hemichannels with a large unitary conductance in vitro. These channels can open at physiological membrane potentials. Functional channels were not formed following mutation of a single amino acid within a conserved protein motif recently shown to be N-glycosylated in rodent Panx1. Together, these findings indicate that zfPanx1 displays properties similar to its mammalian homologues and can potentially play an important role in functions of the outer retina. In mammals, a single pannexin1 gene (Panx1) is widely expressed in the CNS including the inner and outer retinae, forming large-pore voltage-gated membrane channels, which are involved in calcium and ATP signaling. Previously, we discovered that zebrafish lack Panx1 expression in the inner retina, with drPanx1a exclusively expressed in horizontal cells of the outer retina. Here, we characterize a second drPanx1 protein, drPanx1b, generated by whole-genome duplications during teleost evolution. Homology searches strongly support the presence of pannexin sequences in cartilaginous fish and provide evidence that pannexins evolved when urochordata and chordata evolution split. Further, we confirm Panx1 ohnologs being solely present in teleosts. A hallmark of differential expression of drPanx1a and drPanx1b in various zebrafish brain areas is the non-overlapping protein localization of drPanx1a in the outer and drPanx1b in the inner fish retina. A functional comparison of the evolutionary distant fish and mouse Panx1s revealed both, preserved and unique properties. Preserved functions are the capability to form channels opening at resting potential, which are sensitive to known gap junction and hemichannel blockers, intracellular calcium, extracellular ATP and pH changes. However, drPanx1b is unique due to its highly complex glycosylation pattern and distinct electrophysiological gating kinetics. The existence of two Panx1 proteins in zebrafish displaying distinct tissue distribution, protein modification and electrophysiological properties, suggests that both proteins fulfill different functions in vivo. Extracellular ATP is an important signaling molecule throughout the inflammatory cascade, serving as a danger signal that causes activation of the inflammasome, enhancement of immune cell infiltration, and fine-tuning of several signaling cascades including those important for the resolution of inflammation. Recent studies demonstrated that ATP can be released from cells in a controlled manner through pannexin (Panx) channels. Panx1-mediated ATP release is involved in inflammasome activation and neutrophil/macrophage chemotaxis, activation of T cells, and a role for Panx1 in inducing and propagating inflammation has been demonstrated in various organs, including lung and the central and peripheral nervous system. The recognition and clearance of dying cells and debris from focal points of inflammation is critical in the resolution of inflammation, and Panx1-mediated ATP release from dying cells has been shown to recruit phagocytes. Moreover, extracellular ATP can be broken down by ectonucleotidases into ADP, AMP, and adenosine, which is critical in the resolution of inflammation. Together, Panx1, ATP, purinergic receptors, and ectonucleotidases contribute to important feedback loops during the inflammatory response, and thus represent promising candidates for new therapies. The ATP release channel Pannexin1 (Panx1) is self-regulated, i.e. the permeant ATP inhibits the channel from the extracellular space. The affinity of the ATP binding site is lower than that of the purinergic P2X7 receptor allowing a transient activation of Panx1 by ATP through P2X7R. Here we show that the inhibition of Panx1 by ATP is abrogated by increased extracellular potassium ion concentration ([K(+)]o) in a dose-dependent manner. Since increased [K(+)]o is also a stimulus for Panx1 channels, it can be expected that a combination of ATP and increased [K(+)]o would be deadly for cells. Indeed, astrocytes did not survive exposure to these combined stimuli. The death mechanism, although involving P2X7R, does not appear to strictly follow a pyroptotic pathway. Instead, caspase-3 was activated, a process inhibited by Panx1 inhibitors. These data suggest that Panx1 plays an early role in the cell death signaling pathway involving ATP and K(+) ions. Additionally, Panx1 may play a second role once cells are committed to apoptosis, since Panx1 is also a substrate of caspase-3. Normal myotubes and adult innervated skeletal myofibers express the glycoprotein pannexin1 (Panx1). Six of them form a "gap junction hemichannel-like" structure that connects the cytoplasm with the extracellular space; here they will be called Panx1 channels. These are poorly selective channels permeable to ions, small metabolic substrate, and signaling molecules. So far little is known about the role of Panx1 channels in muscles but skeletal muscles of Panx1(-/-) mice do not show an evident phenotype. Innervated adult fast and slow skeletal myofibers show Panx1 reactivity in close proximity to dihydropyridine receptors in the sarcolemma of T-tubules. These Panx1 channels are activated by electrical stimulation and extracellular ATP. Panx1 channels play a relevant role in potentiation of muscle contraction because they allow release of ATP and uptake of glucose, two molecules required for this response. In support of this notion, the absence of Panx1 abrogates the potentiation of muscle contraction elicited by repetitive electrical stimulation, which is reversed by exogenously applied ATP. Phosphorylation of Panx1 Thr and Ser residues might be involved in Panx1 channel activation since it is enhanced during potentiation of muscle contraction. Under denervation, Panx1 levels are upregulated and this partially explains the reduction in electrochemical gradient, however its absence does not prevent denervation-induced atrophy but prevents the higher oxidative state. Panx1 also forms functional channels at the cell surface of myotubes and their functional state has been associated with intracellular Ca(2+) signals and regulation of myotube plasticity evoked by electrical stimulation. We proposed that Panx1 channels participate as ATP channels and help to keep a normal oxidative state in skeletal muscles. Pannexin1 (Panx1) participates in several signaling events that involve adenosine triphosphate (ATP) release, including the innate immune response, ciliary beat in airway epithelia, and oxygen supply in the vasculature. The view that Panx1 forms a large ATP release channel has been challenged by the association of a low-conductance, small anion-selective channel with the presence of Panx1. We showed that Panx1 membrane channels can function in two distinct modes with different conductances and permeabilities when heterologously expressed in Xenopus oocytes. When stimulated by potassium ions (K(+)), Panx1 formed a high-conductance channel of ~500 pS that was permeable to ATP. Various physiological stimuli can induce this ATP-permeable conformation of the channel in several cell types. In contrast, the channel had a low conductance (~50 pS) with no detectable ATP permeability when activated by voltage in the absence of K(+). The two channel states were associated with different reactivities of the terminal cysteine of Panx1 to thiol reagents, suggesting different conformations. Single-particle electron microscopic analysis revealed that K(+) stimulated the formation of channels with a larger pore diameter than those formed in the absence of K(+). These data suggest that different stimuli lead to distinct channel structures with distinct biophysical properties. Pannexin2 (Panx2) is the largest of three members of the pannexin proteins. Pannexins are topologically related to connexins and innexins, but serve different functional roles than forming gap junctions. We previously showed that pannexins form oligomeric channels but unlike connexins and innexins, they form only single membrane channels. High levels of Panx2 mRNA and protein in the Central Nervous System (CNS) have been documented. Whereas Pannexin1 (Panx1) is fairly ubiquitous and Pannexin3 (Panx3) is found in skin and connective tissue, both are fully glycosylated, traffic to the plasma membrane and have functions correlated with extracellular ATP release. Here, we describe trafficking and subcellular localizations of exogenous Panx2 and Panx1 protein expression in MDCK, HeLa, and HEK 293T cells as well as endogenous Panx1 and Panx2 patterns in the CNS. Panx2 was found in intracellular localizations, was partially N-glycosylated, and localizations were non-overlapping with Panx1. Confocal images of hippocampal sections immunolabeled for the astrocytic protein GFAP, Panx1 and Panx2 demonstrated that the two isoforms, Panx1 and Panx2, localized at different subcellular compartments in both astrocytes and neurons. Using recombit fusions of Panx2 with appended genetic tags developed for correlated light and electron microscopy and then expressed in different cell lines, we determined that Panx2 is localized in the membrane of intracellular vesicles and not in the endoplasmic reticulum as initially indicated by calnexin colocalization experiments. Dual immunofluorescence imaging with protein markers for specific vesicle compartments showed that Panx2 vesicles are early endosomal in origin. In electron tomographic volumes, cross-sections of these vesicles displayed fine structural details and close proximity to actin filaments. Thus, pannexins expressed at different subcellular compartments likely exert distinct functional roles, particularly in the nervous system. The different types of cells in the lung, from the conducting airway epithelium to the alveolar epithelium and the pulmonary vasculature, are interconnected by gap junctions. The specific profile of gap junction proteins, the connexins, expressed in these different cell types forms compartments of intercellular communication that can be further shaped by the release of extracellular nucleotides via pannexin1 channels. In this review, we focus on the physiology of connexins and pannexins and describe how this lung communication network modulates lung function and host defenses in conductive and respiratory airways.
Which currently known mitochondrial diseases have been attributed to POLG mutations?
Mutations in the POLG gene have emerged as one of the most common causes of inherited mitochondrial disease in children and adults. They are responsible for a heterogeneous group of at least 6 major phenotypes of neurodegenerative disease that include: 1) childhood Myocerebrohepatopathy Spectrum disorders (MCHS), 2) Alpers syndrome, 3) Ataxia Neuropathy Spectrum (ANS) disorders, 4) Myoclonus Epilepsy Myopathy Sensory Ataxia (MEMSA), 5) autosomal recessive Progressive External Ophthalmoplegia (arPEO), and 6) autosomal dominant Progressive External Ophthalmoplegia (adPEO).
BACKGROUND: Mutations in the gene encoding mitochondrial DNA polymerase gamma (POLG), the enzyme that synthesises mitochondrial DNA (mtDNA), have been associated with a mitochondrial disease-autosomal domit or recessive progressive external ophthalmoplegia-and multiple deletions of mtDNA. Mitochondrial dysfunction is also suspected to participate in the pathogenesis of Parkinson's disease. However, no primary gene defects affecting mitochondrial proteins causing mendelian transmission of parkinsonism have been characterised. We aimed to analyse the gene sequence of POLG in patients with progressive external ophthalmoplegia and their healthy relatives. METHODS: In seven families of various ethnic origins we assessed patients with progressive external ophthalmoplegia and unaffected individuals by clinical, biochemical, morphological, and molecular genetic characterisation and positron emission tomography (PET). FINDINGS: We recorded mutations in POLG in members of all seven families. Clinical assessment showed significant cosegregation of parkinsonism with POLG mutations (p<0.0001), and PET findings were consistent with dopaminergic neuron loss. Post-mortem examination in two individuals showed loss of pigmented neurons and pigment phagocytosis in substantia nigra without Lewy bodies. Furthermore, most women with progressive external ophthalmoplegia had early menopause-before age 35 years. The POLG gene defect resulted in secondary accumulation of mtDNA deletions in patients' tissues. INTERPRETATION: Dysfunction of mitochondrial POLG causes a severe progressive multisystem disorder including parkinsonism and premature menopause, which are not typical of mitochondrial disease. Cosegregation of parkinsonism and POLG mutations in our families suggests that when defective, this gene can underlie mendelian transmission of parkinsonism. RELEVANCE TO PRACTICE: Awareness that mitochondrial POLG mutations can underlie parkinsonism is important for clinicians working in diagnosis of movement disorders, as well as for studies of the genetics of Parkinson's disease. Further, progressive external ophthalmoplegia with muscle weakness and neuropathy can mask symptoms of parkinsonism, and clinicians should pay special attention to detect and treat parkinsonism in those individuals. Mutations in the POLG gene have emerged as one of the most common causes of inherited mitochondrial disease in children and adults. They are responsible for a heterogeneous group of at least 6 major phenotypes of neurodegenerative disease that include: 1) childhood Myocerebrohepatopathy Spectrum disorders (MCHS), 2) Alpers syndrome, 3) Ataxia Neuropathy Spectrum (ANS) disorders, 4) Myoclonus Epilepsy Myopathy Sensory Ataxia (MEMSA), 5) autosomal recessive Progressive External Ophthalmoplegia (arPEO), and 6) autosomal domit Progressive External Ophthalmoplegia (adPEO). Due to the clinical heterogeneity, time-dependent evolution of symptoms, overlapping phenotypes, and inconsistencies in muscle pathology findings, definitive diagnosis relies on the molecular finding of deleterious mutations. We sequenced the exons and flanking intron region from approximately 350 patients displaying a phenotype consistent with POLG related mitochondrial disease and found informative mutations in 61 (17%). Two mutant alleles were identified in 31 unrelated index patients with autosomal recessive POLG-related disorders. Among them, 20 (67%) had Alpers syndrome, 4 (13%) had arPEO, and 3 (10%) had ANS. In addition, 30 patients carrying one altered POLG allele were found. A total of 25 novel alterations were identified, including 6 null mutations. We describe the predicted structural/functional and clinical importance of the previously unreported missense variants and discuss their likelihood of being pathogenic. In conclusion, sequence analysis allows the identification of mutations responsible for POLG-related disorders and, in most of the autosomal recessive cases where two mutant alleles are found in trans, finding deleterious mutations can provide an unequivocal diagnosis of the disease. DNA polymerase γ (pol γ), encoded by POLG, is responsible for replicating human mitochondrial DNA. About 150 mutations in the human POLG have been identified in patients with mitochondrial diseases such as Alpers syndrome, progressive external ophthalmoplegia, and ataxia-neuropathy syndromes. Because many of the mutations are described in single citations with no genotypic family history, it is important to ascertain which mutations cause or contribute to mitochondrial disease. The vast majority of data about POLG mutations has been generated from biochemical characterizations of recombit pol γ. However, recently, the study of mitochondrial dysfunction in Saccharomyces cerevisiae and mouse models provides important in vivo evidence for the role of POLG mutations in disease. Also, the published 3D-structure of the human pol γ assists in explaining some of the biochemical and genetic properties of the mutants. This review summarizes the current evidence that identifies and explains disease-causing POLG mutations.
What is the effect of ivabradine in heart failure after myocardial infarction?
Ιvabradine decreases heart rate and reduces myocardial oxygen demand, increases diastolic perfusion time and improves energetics in ischemic myocardium. Ivabradine protects the myocardium during ischemia, improves left ventricular function in heart failure and reduces remodeling following myocardial infarction. It improves prognosis in patients with coronary artery disease, left ventricular dysfunction and heart rate ≥70 beats per minute, as well as in patients with heart failure and left ventricular dysfunction. The beneficial effects of ivabradine may be due to the reversal of electrophysiological cardiac remodelling in post-MI rats by reduction of functional overexpression of HCN channels. Furthermore, the improvement of cardiac function is related not only to the HR reduction per se but also to modifications in the extracellular matrix.
BACKGROUND: Heart rate reduction (HRR) improves left ventricular (LV) filling, increases myocardial O2 supply, and reduces myocardial O2 consumption, which are all beneficial in congestive heart failure (CHF). However, the long-term effects of HRR on cardiac function and remodeling are unknown. METHODS AND RESULTS: We assessed, in rats with CHF, the effects of long-term HRR induced by the selective I(f) current inhibitor ivabradine (as food admix for 90 days starting 7 days after coronary artery ligation). To assess intrinsic modifications of LV tissue induced by long-term HRR, all parameters were reassessed 3 days after interruption of treatment. Ivabradine decreased heart rate over the 90-day treatment period (-18% versus untreated at 10 mg x kg(-1) x d(-1)), without modifying blood pressure, LV end-diastolic pressure, or dP/dt(max/min). Ivabradine significantly reduced LV end-systolic but not end-diastolic diameter, which resulted in preserved cardiac output due to increased stroke volume. In the Langendorff preparation, ivabradine shifted LV systolic but not end-diastolic pressure-volume relations to the left. Ivabradine decreased LV collagen density and increased LV capillary density without modifying LV weight. Three days after interruption of treatment, the effects of ivabradine on LV geometry, shortening, and stroke volume persisted despite normalization of heart rate. CONCLUSIONS: In rats with CHF, long-term HRR induced by the selective I(f) inhibitor ivabradine improves LV function and increases stroke volume, preserving cardiac output despite the HRR. The improvement of cardiac function is related not only to the HRR per se but also to modifications in the extracellular matrix and/or function of myocytes as a consequence of long-term HRR. AIMS: Effects of the bradycardic agent ivabradine on regional blood flow, contractile function, and infarct size were studied in a pig model of myocardial ischaemia/reperfusion. Heart rate reduction by beta-blockade is associated with negative inotropism and unmasked alpha-adrenergic coronary vasoconstriction. Ivabradine is the only available bradycardic agent for clinical use. METHODS AND RESULTS: Anaesthetized pigs were subjected to 90 min controlled left anterior descending coronary artery hypoperfusion and 120 min reperfusion. Regional blood flow was measured with microspheres, regional function with sonomicrometry, and infarct size with triphenyl tetrazolium chloride staining. Pigs received placebo or ivabradine (0.6 mg/kg i.v.) before or during ischaemia or before reperfusion, respectively. Pre-treatment with ivabradine reduced infarct size from 35 +/- 4 (SEM) to 19 +/- 4% of area at risk (AAR). Ivabradine 15-20 min after the onset of ischaemia increased regional myocardial blood flow from 2.12 +/- 0.31 to 3.55 +/- 0.56 microL/beat/g and systolic wall thickening from 6.7 +/- 1.0 to 16.3 +/- 3.0%; infarct size was reduced from 12 +/- 4 to 2 +/- 1% of AAR. Ivabradine 5 min before reperfusion still reduced infarct size from 36 +/- 4 to 21 +/- 5% of AAR. The benefit of ivabradine on flow and function was eliminated by atrial pacing, but part of the reduction of infarct size by ivabradine was not. CONCLUSION: Ivabradine's protection goes beyond heart rate reduction. Collaborators: Grancelli H, Freedman B, Eber B, Vanoverschelde JL, Finkov B, Yotov Y, Tardif JC, Hu D, Lau C, Hradec J, Hildebrandt P, Eha J, Peuhkurinen K, Danchin N, Steg PG, Meinertz T, Vardas P, Borbola J, Mulcahy D, Maggioni A, Erglis A, Jirgensons J, Kalnins U, Laucevicius A, Dickstein K, Ruzyllo W, Tendera M, Seabra-Gomes R, Capalneanu R, Belenkov Y, Mareev Y, Murin J, Rakovec P, Macaya C, Dellborg M, Lüscher TU, van Gilst W, Oto A, Ford I, Fox K, Hall A, Parkhomenko A, Robertson M, Weir C, Aziz J, Kean S, Wilson R, Thygesen K, Frenneaux M, Jondeau G, Camm AJ, Dargie H, Kjekshus J, Murray G, Ahuad Guerrero RA, Allall OA, Amuchastegui M, Buscema JJ, Bustos B, Cartasegna LR, Cohen Arazi H, Ferdez AA, Fuselli JJ, Guzmén LA, Hasbani E, Ibañez JO, Iglesias RM, Lembo LA, Luciardi HL, Luquez HA, Montaña OR, Nul DR, Orlandini AD, Perna ER, Sanchez A, Sanjurjo MS, Schygiel PO, Sinisi VA, Sokn FJ, Thierer J, Del Valle Lobo Marquez LL, Varini S, Vogel D, Alford K, Amerena J, Arnolda L, Atherton J, Bradley J, Cameron J, Colquhoun D, Counsell J, Fitzpatrick A, Horowitz J, Ireland M, Karrasch J, Kaye D, Lattimore JD, Marwick T, O'Shea J, Owensby D, de Pasquale C, Prior D, Rogers J, Sindone A, Singh BB, Stickland J, Szto G, Tofler G, Vogl E, Waites J, Walsh W, Eber E, Huber K, Lang I, Pichler M, Chenu P, Dendale PA, François PA, Friart A, Goethals M, Materne P, van Mieghem W, Missault L, Vachiery JL, Vanderheyden M, Chompalova B, Denchev S, Donova T, Dzhurzdhev A, Georgiev B, Gotchev D, Goudev A, Grigorov M, Guenova D, Hergeldjieva V, Kamenova Z, Nachev C, Penkov N, Perchev I, Raev D, Sirakova V, Taseva T, Torbova S, Tzekova M, Baird M, Bernstein V, Chehayeb R, Constance C, Coutu B, Desrochers D, Fortin C, Glanz A, Haddad H, Heath J, Hill LL, Klinke WP, Kouz S, Lalani A, Lauzon C, Lepage S, Lonn E, Ma P, Matangi M, Nawaz S, Pandey S, Parker JD, Parker JO, Poirier P, Raco D, Rajda M, Rebane T, Rupka D, Savard D, Syan GS, Talbot P, Tardif JC, To TB, Vakani MT, Vertes GE, Yao L, Dong Y, Gai L, Ge JB, Hu D, Lv S, Sun Y, Wang W, Wang X, Yan X, Yuan Z, Zhang F, Ballek L, Drazka J, Fébik L, Florian J, Hradec J, Kaislerová M, Karetová D, Jerábek O, Kotík L, Krejcova H, Kryza R, Kuchar J, Lavicka V, Maratka T, Marcinek G, Penicka M, Povolný J, Sochor K, Soucek M, Spacek R, Spinar J, Stípal R, Sulda M, Vencour D, Vitovec J, Vojacek J, Vojtísek P, Agner E, Asklund M, Brønnum Schou J, Dahlstrøm CG, Dodt KK, Egstrup K, Gøtzsche L, Gøtzsche O, Haghfelt T, Hildebrandt P, Jakobsen T, Jensen G, Klarlund K, Køber L, Larsen CT, Larsen J, Lind Rasmussen S, Lysko Svendsen T, Markenvard J, McNair A, Nielson H, Pedersen L, Petersen J, Ralfkiaer N, Rickers H, Rokkedal J, Romer F, Roseva Nielsen N, Scheibel M, Sejersen H, Skagen K, Stentebjerg SE, Torp-Pedersen C, Tuxen C, Vigholt E, Averina O, Eha J, Kolbassova O, Sildmäe S, Vahula V, Viigimaa M, Harjola VP, Luoma J, Melin J, Peuhkurinen K, Aliot E, Barthelemy JC, Bauer F, Beaune J, Belin A, Bodur G, Boudahne A, Bourdon A, Bouvier JM, Carlioz R, Chati Z, Cherbi C, Chevalier JM, Chevrier J, Claudon O, Colin P, Dambrine P, Danchin N, Decoulx E, Demarcq JM, Doucet B, Drawin T, Dubois-Rande JL, El Mansour N, Escande M, Fournier PY, Funck F, Gabrovescu M, Galinier M, Galley D, Gay A, Genest M, Godenir JP, Guillot JP, Gully C, Habib G, Huyghe de Mahenge A, Jaboureck O, Kahn JC, Khalife K, Khanoyan P, Koenig A, Leborgne L, Lemoine C, Magnin D, Mann H, Mansourati J, Martelet M, Matina D, Meurice T, Olive TG, Ovize M, Perret T, Pierre-Justin E, Riou A, Roudaut R, Roul G, Roynard JL, Sellier P, Slama M, Soto FX, Thisse JY, Wolf JE, Ammer K, Appel KF, Baar M, Bauknecht C, Baumann G, Bergmann K, Böhm M, Bosch R, Bott J, Cieslinski G, Deissner M, Drescher T, Droese K, Figulla HR, Frick HM, Fries P, Gärtner J, Gola G, Gonska BD, Grooterhorst P, Hasenfuss G, Haverkamp W, Heckel D, Hengstenberg C, Hering R, Heuer H, Hoppe U, Jahnke N, Jeserich M, Katus H, Kleinertz K, Kombächer HD, Lange R, Lehmann G, Meinertz T, Müller O, Münzel T, Natour M, Nienaber C, Oeff M, Pötsch T, Proskynitopoulos N, Rüdell U, Rummel R, Rupprecht HJ, von Schacky C, Schenkenberger I, Schmidt J, Schreckenberg A, Schuler G, Schultheiss HP, Seidl K, Spanier C, Spengler U, Steindorf J, Strasser R, Taggeselle J, Tammen A, Werdan K, Windstetter U, Winkelmann BR, Wolde CH, Zahorsky R, Al-Zoebi A, Alexopoulos D, Anastasiou-Nana M, Apostolou T, Fotiadis I, Hatzinikolaou-Kotsakou E, Kallikazaros I, Kapordelis C, Karvounis H, Kolettis T, Koliopoulos N, Kremastinos D, Kyriakides Z, Manolis A, Papadopoulos C, Pras A, Pyrgakis VN, Siogas K, Theodorakis G, Tryposkiadis F, Tziakas D, Vardas P, Lee K, Barsi B, Borbola J, Cziráki A, Dézsi CA, Edes I, Farsang C, Harmati L, Juhász A, Kovács A, Lakatos F, Lippai J, Lupkovics G, Matoltsy A, Mohácsi A, Mohay A, Nagy A, Nagy K, Nagy L, Nyárádi A, Pálinkás A, Piros G, Polgár P, Préda I, Regos L, Rumi G, Sármán P, Sereg M, Sidó Z, Tahy A, Takács J, Tomcsányi J, Tóth K, Váradi A, Vegh G, Veress G, Zámolyi K, Barton J, Crean P, Daly K, Foley D, Alberti E, Ambrosio G, Barbuzzi S, Bellone E, Buia E, Capucci A, Carbonieri E, Cardona N, Della Casa S, Cocchieri M, Colombo A, Cosmi F, De Cristofaro M, Ferrari R, Fuscaldo G, Gavazzi A, Giannuzzi P, Giustiniani S, Ingrilli F, Leghissa R, De Luca I, Maresta A, De Matteis C, Minneci C, Mos L, Paparoni S, Perna B, Pettinati G, Pinelli G, Pizzimenti G, Porcu M, Proietti G, Proto C, Pulitano G, Reggianini L, Santini M, Uguccioni M, Urbinati S, Zanetta M, Zanini R, Erglis A, Gailiss E, Gersamija A, Keisa M, Libins A, Ozolina MA, Stoma M, Volans E, Berukstis E, Grabauskiene V, Kibarskis A, Kirkutis A, Marcinkeviciene J, Naudziunas A, Petrulioniene Z, Varoneckas G, Zaliunas R, Bartels GL, van Beek GJ, van den Berg BJ, Bruning TA, Cornel JH, Daniels MC, Dijkgraaf R, Fast J, Freericks MP, Galema TW, Göbel EJ, Hamer LH, van der Heijden R, Herrman JP, Hoedemaker G, Holwerda NJ, Hoogslag PA, Jaarsma W, Jap Tjoen San WT, van Kempen LH, Kirkels JH, Kragten JA, Leenders CM, Linssen GC, Lionarons RJ, Maas AH, Michels HM, de Milliano PA, Nagelsmit MJ, Nierop PR, Pinto YM, Robles De Medina R, van Rossum P, van Rugge FP, Somer ST, Swart H, Thijssen H, van der Veen M, Verheul JA, van Vlies B, Voors AA, Wesdorp JC, van Wijk LM, Willems AR, Winter JB, Withagen AJ, van der Zwaan C, Zwart PA, Atar D, Dickstein K, Myhre EP, Achremczyk P, Andrzejak R, Baska J, Bloch C, Dluzniewski M, Drozdowski P, Goch JH, Janik K, Janion M, Jaworska K, Kalarus Z, Kawecka-Jaszcz K, Kozlowski A, Krupa E, Krynicki R, Krzciuk M, Krzeminska-Pakula M, Kubica J, Kurowski M, Kuzniar J, Loboz-Grudzien K, Mazurek W, Miekus P, Musial W, Opolski G, Piepiorka M, Piotrowski W, Piwowarska W, Pluta W, Ponikowski P, Pulkowski G, Pusz T, Ruszkowski P, Ruzyllo W, Rynkiewicz A, Sinkiewicz W, Skura M, Slowinski S, Szolkiewicz M, Szpajer M, Targonski R, Tendera M, Tracz W, Trojnar R, Trusz-Gluza M, Wodniecki J, Wrabec K, Zadrozna Z, Zinka E, Aguiar J, Carvalho N, Ferreira Da Silva G, Freitas J, Lousada N, Oliveira Soares A, Paisana Lopes JP, Providencia LA, Salgado A, Teixeira M, Apetrei E, Arsenescu C, Avram R, Babes K, Bruckner I, Capalneanu R, Carasca E, Cinteza M, Craiu E, Dan GA, Datcu MD, Dimulescu DR, Dorobantu M, Dragomor D, Dragulescu IS, Dumitrascu DL, Georgescu IM, Ionescu DD, Ionascu-Fometescu CR, Kiss L, Macarie C, Manitiu I, Minescu B, Nanea T, Olariu C, Olinic NC, Opris M, Pop C, Radoi M, Radu I, Sinescu CJ, Tanaseanu CM, Tase A, Tintoiu I, Tomescu M, Topolnitchi L, Vintila M, Vladoianu M, Arkhipov MV, Aroutiounov GP, Azarin OG, Barbarash OL, Bart BY, Beloussov YB, Bychkova L, Chumakova GA, Glezer MG, Golukhova E, Gorbachenkov AA, Gordeev IG, Ivleva AY, Karpov YA, Karpov YB, Kastanaian AA, Kisliak OA, Kobalava JD, Konyakhin AY, Khrustalev OA, Kuimov AD, Kukes AG, Lopatin YM, Mareev VY, Moiseeva OM, Mkrtchyan VR, Nedogoda SV, Orlov VA, Perepech NB, Pimenov LT, Pozdnyakov YM, Rodoman GV, Rudnev DV, Sayganov SA, Shlyakhto EV, Shostak NA, Shpektor AV, Sidorenko BA, Sorokin LA, Stryuk RI, Svistov AS, Tankhilevich BM, Tereschenko SN, Tsyba LP, Vasyuk YA, Vertkine AL, Yakhontova PK, Yakusevich VV, Yakushin SS, Zadionchenko VS, Zateyshchikov DA, Zhilyaev EV, Bada V, Bugán V, Gonsorcík J, Kamenský G, Kmec J, Micko K, Murín J, Pella D, Sojka G, Vahala P, Bombek M, Kanic V, Markez J, Melihen-Bartolic C, Rakove P, Skrabl-Mocnik F, Slemenik-Pusnik C, Balaguer Recena J, Bertomeu Martinez V, Bruguera Cortada J, Calvo Gomez C, Calvo Iglesias F, Caparros Valderrama J, Casares Garcia G, Ferdez Alvarez R, Galve E, Garcia De Burgos F, Grande A, Gusi Tragant G, Iglesias Alonso LF, Iglesias Cubero G, Illa Gay J, Jimenez Navarro M, López Bescós L, López García-Aranda V, Macaya De Miguel C, Noriega Peiro F, Paz Bermejo MA, Perez Villa F, Romero Hinojosa JA, San Román Calvar A, Sevilla Toral B, Sola Casado R, Bandh A, Blomgren J, Dellborg M, Herlitz J, Ohlin H, Ullman B, Delabays A, Dubach P, Eeckhout E, Gallino A, Hess O, Moccetti T, Vontobel H, Acarturk E, Ergene O, Erol K, Kozan O, Mutlu B, Ural D, Yilmaz H, Amosova K, Barna O, Batushkin V, Bazylevych A, Bereznyakov I, Dyadyk A, Dzyak G, Girina O, Glushko L, Goloborodko B, Karpenko O, Khomazyuk T, Kolchin Y, Kolomiets S, Korkushko O, Korzh O, Kovalenko V, Kovalsky I, Krayz I, Kubyshkin V, Lutay M, Mostovoy Y, Netyazhenko V, Parkhomenko A, Perepelytsya M, Pertseva T, Polyvoda S, Putintsev V, Rishko LM, Rudyk Y, Sakharchuk I, Semidotska Z, Seredyuk N, Serkova V, Sharuk O, Slyvka Y, Soldatchenko S, Stadnyuk L, Storozhuk B, Tashchuk V, Tseluyko V, Vatutin M, Vizir V, Vlasenko M, Voronkov L, Yurlov V, Zharinov O, Baig MW, Brady A, Brooks N, Brooksby P, Crook JR, Dutka D, Francis CM, Greaves K, Groves P, Hall A, Kadr H, Lindsay S, Moriarty A, Purvis J, Rozkovec A, Saltissi S, Stewart M, Timmis A, Williams S. We tested the hypothesis that heart rate (HR) reduction, induced by the selective hyperpolarization-activated current inhibitor ivabradine (Iva), might improve left ventricular (LV) function, structure, and electrical remodeling in severe post-myocardial infarction (MI) chronic heart failure (HF). MI was produced in adult male Wistar rats. After 2 mo, echocardiography was performed before the randomization into MI and MI + Iva (10 mg x kg(-1) x day(-1)) groups. After 3 mo of treatment, echocardiography and 24-h telemetry were recorded. Cardiac collagen, mRNA, and protein expressions of angiotensin-converting enzyme (ACE) and ANG II type 1 (AT(1)) receptor were quantified. As a result, at 2 mo post-MI, all rats displayed severe congestive HF signs (ejection fraction < 30%). At 5 mo post-MI, body and heart weights were similar in the MI and MI + Iva groups. LV ejection fraction and LV end-diastolic pressure were worsened in the MI group, whereas both were improved with Iva. Iva reduced HR by 10.4% (P < 0.03 vs. MI) and ventricular premature complexes by 89% (P < 0.03) and improved HR variability (standard deviation of the RR interval) by 22% (P < 0.05). There were no effects of Iva on PR, QRS, and QT durations. Interstitial fibrosis in the MI-remote LV was markedly reduced by Iva (4.0 +/- 0.1 vs. 1.8 +/- 0.1%, P < 0.005). Increases in ventricular gene and protein expressions of ACE and AT(1) receptor in MI were completely blunted by Iva. In conclusion, these data indicated that HR reduction by Iva prevents the worsening of LV dysfunction and remodeling that may be related to a downregulation of cardiac renin-angiotensin-aldosterone system transcripts. Such beneficial effects of Iva on cardiac remodeling open new clinical perspectives for the treatment of severe HF. We compared the effects of heart rate reduction (HRR) by the hyperpolarization-activated pacemaker current (I(f)) channel inhibitor ivabradine (MI+Iva) and the beta(1)-blocker atenolol (MI+Aten) on ventricular remodeling and perfusion after myocardial infarction (MI) in middle-aged (12 mo) Sprague-Dawley rats. Mean HRR was virtually identical in the two treated groups (19%). Four weeks after coronary artery ligation, maximal myocardial perfusion fell in the MI group but was preserved in infarcted rats treated with either Iva or Aten. However, coronary reserve in the remodeled hearts was preserved only with Iva, since Aten treatment elevated baseline perfusion in response to a higher wall stress. The higher maximal perfusion noted in the two treated groups was not due to arteriogenesis or angiogenesis. Plasma levels of angiotensin (ANG) II and myocardial ANG type 1 (AT(1)) receptor and transforming growth factor (TGF)-beta1 were reduced during the first week of treatment by both Iva and Aten. Moreover, treatment also reduced arteriolar perivascular collagen density. Despite these similar effects of Iva and Aten on vascularity and ANG II, Iva, but not Aten, attenuated the decline in ejection fraction and lowered left ventricular (LV) end-diastolic volume (LVEDV)-to-LV mass ratio, determined by echocardiography. In conclusion, 1) Iva has advantages over Aten in postinfarction therapy that are not due to differential effects of the drugs on heart rate, and 2) age limits growth factor upregulation, angiogenesis, and arteriogenesis in the postinfarcted heart. Ivabradine is an I(f) current inhibitor, that has documented antianginal efficacy. The BEAUTIFUL trial tested ivabradine against placebo in a large population of 10,917 patients in sinus rhythm, with coronary artery disease and left ventricular dysfunction, defined as left ventricular ejection fraction < or =35%. Overall, there was no impact of ivabradine on the primary end-point of the trial (cardiovascular mortality, hospitalisation for myocardial infarction, new onset or worsening heart failure). In the placebo arm of the trial, baseline heart rate > or = 70 bpm was associated with an increased risk of cardiovascular mortality, myocardial infarction, heart failure and coronary revascularisation. In the subgroup of patients with a baseline heart rate > or =70 bpm, treatment with ivabradine resulted in a significant, 36% reduction in the risk of myocardial infarction and a 20% reduction in the need for coronary revascularisation. Ivabradine was well tolerated, with an increased rate of treatment discontinuation, mainly due to bradycardia, compared with placebo. Because of its safety and efficacy to control angina, ivabradine should be considered first-line antianginal treatment in coronary artery disease patients with left ventricular dysfunction and increased heart rate, already receiving beta-blocker therapy or in whom these medications are not tolerated. The BEAUTIFUL (morBidity-mortality EvAlUaTion of the If inhibitor ivabradine in patients with coronary artery disease and left ventricULar systolic dysfunction) study assessed the morbidity and mortality benefits of the HR-lowering agent ivabradine. The placebo arm of the BEAUTIFUL trial was a large cohort of patients with stable coronary artery disease (CAD) and left ventricular systolic dysfunction. A subanalysis in the placebo group tested the hypothesis that elevated resting HR at baseline was a marker for subsequent cardiovascular death and morbidity. The primary aim of the study was to test whether lowering the HR with ivabradine reduced cardiovascular death and morbidity in patients with CAD and left ventricular systolic dysfunction. In the overall analysis, reduction in HR with ivabradine did not improve cardiac outcomes compared with placebo. The most important finding of the study was that patients with high baseline HR had an increase in serious cardiovascular events including death (34%), hospital admission secondary to congestive heart failure (53%), acute myocardial infarction (46%), or revascularization procedure (38%). In addition, in the subset analysis focusing on patients with baseline HR > or =70 bpm and left ventricular ejection fraction <40% the agent resulted in a 36% decrease in hospital admissions secondary to fatal and nonfatal myocardial infarction and a 30% decrease in coronary revascularization. The first practical implication from the study includes that baseline HR should be recorded in addition to other risk factors such as BP and lipid profile, in the follow-up of patients with CAD. Attempts should be made to achieve HR <70 bpm by cardiac rehabilitation and routine use of appropriately dosed beta-blockers. Despite the neutral results obtained in the BEAUTIFUL study, ivabradine could be administered to the subgroup of patients in whom HR <70 bpm is not achieved despite proper dosing of beta-blockers and in those in whom beta-blockers are contraindicated. Furthermore, in clinical practice, ivabradine may be helpful for patients with stable CAD who have a high HR while receiving beta-blockers. Future studies are needed to confirm the hypothesis that single reduction of HR can improve cardiovascular prognosis. BACKGROUND AND PURPOSE: Recent clinical data suggest beneficial effects of ivabradine, a specific heart rate (HR)-lowering drug, in heart failure patients. However, the mechanisms responsible for these effects have not been completely clarified. Thus, we investigated functional/molecular changes in I(f), the specific target of ivabradine, in the failing atrial and ventricular myocytes where this current is up-regulated as a consequence of maladaptive remodelling. EXPERIMENTAL APPROACH: We investigated the effects of ivabradine (IVA; 10 mg·kg(-1) ·day(-1) for 90 days) on electrophysiological remodelling in left atrial (LA), left ventricular (LV) and right ventricular (RV) myocytes from post-mycardial infarcted (MI) rats, with sham-operated (sham or sham + IVA) rats as controls. I(f) current was measured by patch-clamp; hyperpolarization-activated cyclic nucleotide-gated (HCN) channel isoforms and microRNA (miRNA-1 and miR-133) expression were evaluated by reverse transcription quantitative PCR. KEY RESULTS: Maximal specific conductance of I(f) was increased in MI, versus sham, in LV (P < 0.01) and LA myocytes (P < 0.05). Ivabradine reduced HR in both MI and sham rats (P < 0.05). In MI + IVA, I(f) overexpression was attenuated and HCN4 transcription reduced by 66% and 54% in LV and RV tissue, respectively, versus MI rats (all P < 0.05). miR-1 and miR-133, which modulate post-transcriptional expression of HCN2 and HCN4 genes, were significantly increased in myocytes from MI + IVA. CONCLUSION AND IMPLICATION: The beneficial effects of ivabradine may be due to the reversal of electrophysiological cardiac remodelling in post-MI rats by reduction of functional overexpression of HCN channels. This is attributable to transcriptional and post-transcriptional mechanisms. AIM: To study effects of ivabradin on clinicohemodynamic and prognostic parameters in patients after myocardial infarction (MI) with systolic chronic cardiac failure (SCCF). MATERIAL AND METHODS: A population-based randomized prospective trial enrolled 49 patients (40 males--81.6%, mean age 63.1 +/- 8.1 years) with sinus rhythm and a longer than 3 month history of MI. The patients were randomized into 2 groups: 23 patients of group 1 received standard treatment plus ivabradin, 26 patients of group 2 received standard treatment alone. Follow-up was 36.1 +/- 6.2 months. We analysed the trend in heart rate (HR), blood pressure (BP), parameters of echocardiography, ECG, levels of electrolytes, creatinin in blood plasma, frequency of hospitalizations, recurrent non-fatal MI and lethality (combined endpoint). RESULTS: In the end of the trial ivabradin significantly decreased HR from 71 to 64 b/m. Frequency of combined end point of efficacy was 30.4 and 50% in group 1 and 2, respectively. In group 1 primary end point in high baseline HR occurred more frequently than in HR < 70 b/m in 6 (50%) and 1 (9.1%) cases, respectively, but these differences were not significant (p = 0.068). In group 2 the differences were significant--9 (90%) and 4 (25%) cases, respectively (p = 0.004). By none of the parameters of ECG, plasma electrolytes, creatinine level significant intergroup differences were found. CONCLUSION: In the same trend in BP and ECG, group 1 patients showed significant and more pronounced HR lowering than group 2 patients. Addition of ivabradin to standard treatment of SCCF after MI promoted less frequency of hospitalizations, recurrent non-fatal MI, fatal cardiovascular events. This effect was especially strong in high baseline HR. Major steps have been made in the treatment of ischemic heart disease from the discovery of nitrates as antianginal medication to the techniques of percutaneous angioplasty. This incredible therapeutic progress has resulted in a reduced incidence of ischemic heart disease and related mortality and morbidity. However, statistical and epidemiological data indicate that in ischemic heart disease, despite the achievement of great success, there is a necessity for a further step toward treatment, considering the fact that the characteristics of this population are changing (increased prevalence of subendocardial infarction compared with classic transmural infarction, especially in the elderly population). Furthermore, the need for alternative therapeutic approaches to traditional ones is recognized. Ranolazine is a selective inhibitor of Na channels that prevents pathological extension of late Na current developing in the ischemic myocardial cell. This current is responsible for calcium overload, with consequent impairment of diastolic relaxation. Ranolazine reduces Na overload induced by calcium and improves diastolic relaxation and coronary subendocardial flow, without affecting hemodynamic parameters such as blood pressure, heart rate, or inotropic state of the heart, avoiding undesirable side effects. Efficacy of ranolazine has been evaluated in several trials, using clinical and instrumental endpoints (MARISA and CARISA) or, more recently, using endpoints such as mortality and reinfarction (ERICA and MERLIN-TIMI 36). Ivabradine acts through the inhibition of late Na current (also known as If), which controls the spontaneous diastolic depolarization of sinus node cells. The partial inhibition of these channels reduces the frequency of sinus node action potential initiation, resulting in decreased heart rate without effects on contractility, atrio-ventricular conduction, or repolarization. The BEAUTIFUL trial has tested whether the effect of ivabradine in lowering heart rate is able to reduce mortality and cardiovascular morbidity in patients with coronary artery disease and left ventricular systolic dysfunction. The most significant results were obtained in the subgroup of patients with life-limiting exertional angina. In this group, ivabradine significantly reduced the primary endpoint, a composite of cardiovascular death, hospitalization for fatal and nonfatal acute myocardial infarction (AMI) or heart failure, by 24%, and hospitalizations for AMI by 42%. In the subgroup of patients with baseline heart rate >70 bpm, hospitalizations for AMI and revascularization were reduced by 73% and 59%, respectively. Chronic stable angina pectoris (CSAP) is the most common manifestation of coronary artery disease (CAD). Angina pectoris occurs as a result of an imbalance between myocardial perfusion and the demands of the myocardium. Elevated heart rate (HR) is an important pathophysiological variable that increases myocardial oxygen demand, and also limits tissue perfusion by reducing the duration of diastole during which most myocardial perfusion occurs. Elevated resting HR represents a significant predictor of all-cause and cardiovascular mortality in the general population and patients with cardiovascular disease (CVD) because it assists the progression of CVD through the development of atherosclerosis, plaque destabilization, and initiation of arrhythmias. Since β-blockers have been found to reduce HR, therefore, they are currently viewed as the first line therapy for CSAP and are associated with an improved prognosis after acute myocardial infarction (AMI) or congestive heart failure (CHF). The classical treatments for HR reduction have shown negative aspects, such as β-blockers therapy which exerts negative effects on regional myocardial blood flow and function when HR reduction is eliminated by atrial pacing. Calcium channel antagonists functionally antagonize coronary vasoconstriction mediated through α-adrenoreceptors, and are thus devoid of this undesired effect, but the compounds are nevertheless negative inotrope. Ivabradine (IVA), a pure HR lowering drug, reduces the demand of myocardial oxygen during exercise, contributes to the restoration of oxygen balance and is therefore beneficial in chronic CVD. No relevant negative effects have been observed on cardiac conduction, contractility, relaxation, repolarization or blood pressure (BP). Beneficial effects of IVA have been noticed in CSAP and CHF, with optimal tolerability profile due to selective interaction with I(f) channel of sino atrial node cells. More recently, IVA has been highly recommended to be used in patients with CAD in association with β-blockers. This review highlights the importance of IVA in the treatment of ischemic heart disease. AIMS: To test the effect of ivabradine on the outcomes in a broad population with left-ventricular (LV) systolic dysfunction with coronary artery disease (CAD) and/or heart failure (HF). METHODS AND RESULTS: Individual trial data from BEAUTIFUL and SHIFT were pooled to evaluate the effect of ivabradine on the outcomes in patients with LV dysfunction and heart rate ≥ 70 b.p.m. The pooled population (n = 11 897; baseline age 62.3 ± 10.4 years, heart rate 79.6 ± 9.2 b.p.m., and LV ejection fraction 30.3 ± 5.6%) was well treated according to current recommendations (87% beta-blockers, 90% renin-angiotensin system inhibitors). Median follow-up was 21 months. Treatment with ivabradine was associated with a 13% relative risk reduction for the composite of cardiovascular mortality or HF hospitalization (P < 0.001 vs. placebo); this was driven by HF hospitalizations (19%, P < 0.001). There were also significant relative risk reductions for the composite of cardiovascular mortality, HF hospitalizations, or myocardial infarction (MI) hospitalization (15%, P < 0.001); cardiovascular mortality and non-fatal MI (10%, P = 0.023); and MI hospitalization (23%, P = 0.009). Similar results were found in patients with differing clinical profiles. Ivabradine was well tolerated. CONCLUSION: Ivabradine may be important for the improvement of clinical outcomes in patients with LV systolic dysfunction and heart rate ≥ 70 b.p.m., whatever the primary clinical presentation (CAD or HF) or clinical status (NYHA class).
What is the mode of inheritance of Wilson's disease?
Wilson's disease (WD) is an autosomal recessive disorder.
In a survey in Israel of 50 patients with Wilson's disease, it was found that this disease occurred in all ethnic groups. In the Arab patients there was a significantly early age of onset and the disease followed a more severe course than that in the Jewish patients. The overall sex ratio of patients was nearly 1:1, and genetic analysis of 20 families confirmed an autosomal recessive mode of inheritance. The very similar age of onset and type of disease within sibships and the varying ages of onset noted between the Arab and Jewish patients suggest that the disease is genetically heterogeneous. Dermatoglyphics of 11 patients with Wilson's disease and 16 of their clinically asymptomatic relatives of first degree were investigated; 11 of the latter ones were heterozygous in agreement with the turn over rates of Cu-67, 12 under the assumption of autosomal recessive inheritance. On the finger tips the Mb. Wilson patients showed 52.7% whorls, their heterozygous relatives about 40%; compared with our controls (males 33.16%, females 28.82%, Aue-Hauser, 1970) that means a strong increase of this pattern type. On the palm the high frequency of hypothenar patterns in homo- and heterozygotes for Wilson's disease and of loops with accessory triradius in the 4th interdigitum of the patients with Wilson's disease was striking. Wilson's disease is an inborn error of copper metabolism, characterised by raised liver-copper concentrations and low serum levels of copper and caeruloplasmin. The autosomal recessive mode of inheritance strongly suggests that mutation of a single gene causes the impairment of both caeruloplasmin synthesis and biliary copper excretion. The normal infant is born with the biochemical features of Wilson's disease (very high liver-copper levels and low serum copper and caeruloplasmin). Induction of normal copper metabolism after birth results in a fall in liver-copper concentrations and rise in serum caeruloplasmin. The repression of normal copper metabolism in the fetus and its induction after birth is probably regulated by a controller gene. It is suggested that mutation of a controller rather than a structural gene underlies the pathogenesis of Wilson's disease and that the disease results from failure to switch from the positive copper balance of the fetus to the normal copper balance of the child. Two problems relating to segregation analysis for Wilson's disease are discussed and a practical solution is presented. A problem in the ascertainment of families with Wilson's disease is illustrated by comparing segregation ratios calculated by the single selection, complete truncate, and multiple incomplete selection methods. The effect on the segregation ratio of exclusion from the analysis of those sibs who had died of other diseases at a young age is also discussed and a method of adjustment of the number of the affected using the data on age at onset is proposed. The segregation ratio by multiple incomplete selection (Weinberg proband method) after adjustment for those sibs who had died of other diseases was 0.243, consistent with the theoretical value for autosomal recessive inheritance. The segregation ratio calculated by the single selection method tended to give a lower value, while that calculated by the complete truncate method was greater than the theoretical value. Recessive inheritance is, however, supported. The actual effect of exclusion of those sibs who had died of other diseases on gene frequency estimation is shown to be very small. We report on an otherwise healthy female, mother of two children, with severe decompensated liver cirrhosis due to an iron overload and Wilson's disease. The patient was considered heterozygote for hemochromatosis on the basis of the autosomal recessive inheritance for hemochromatosis, the frequency of the hemochromatosis gene, and the laboratory parameters defining her iron overload. The case is interesting because of the coincidence of Wilson's disease and excessive iron storage. The clinical features of two children of a family with rapidly progressive extrapyramidal-pyramidal-dementia complex have been described. Inheritance seems most likely to be autosomal recessive. Magnetic resoce imaging results of brain were negative. Even so, the authors argued in favor of a diagnosis of Hallervorden-Spatz disease because the cases fulfilled the clinical criteria for diagnosis of this disease. Apart from the negative magnetic resoce findings, the other unusual feature was the early development of levodopa-induced dyskinesia. Few conditions need to be considered in the differential diagnosis of a childhood-onset rapidly progressive extrapyramidal syndrome. Such conditions include Wilson's disease, Hallervorden-Spatz disease (HSD), juvenile form of Huntington's disease, juvenile neuronal ceroid lipofuscinosis, early-onset Machado-Joseph disease neuroacanthocytosis, storage disorders, and variant form of dopa-response dystonias (DRD). Rarer conditions are Leigh's disease, Lafora body disease, and dentato-rubro-pallido-luysian atrophy. HSD is a rare disorder characterized by progressive extrapyramidal dysfunction and dementia. Onset is most commonly in late childhood or early adolescence. The disease can be familial or sporadic. When familial, it is inherited recessively and has been linked to chromosome 20. Recently, a mutation in the pantothenate kinase (PANK2) gene on band 20pl3 has been described in patients with typical HSD. HSD produces typical magnetic resoce imaging (MRI) changes in brain, aiding in antemortem diagnosis. The typical finding is of bilaterally symmetrical hyperintense signal changes in the external segment of globus pallidus, with surrounding hypointensity on T(2)-weighted image. These imaging features are fairly diagnostic and have been termed the "eye-of-the tiger sign". The hyperintensity represents pathologic changes, including gliosis, demyelination, neuronal loss, and axonal swelling, and the surrounding hypointensity is caused by loss of signal secondary to iron deposition. Described herein are the clinical aspects of a family with autosomal recessive inheritance with rapidly progressive extrapyramidal-pyramidal-dementia complex but with negative brain MRI results. The diagnosis should be considered a variant form of HSD. Wilson's disease (WD) is an inborn error of copper metabolism caused by a mutation to the copper-transporting gene ATP7B. The disease has an autosomal recessive mode of inheritance, and is characterized by excessive copper deposition, predomitly in the liver and brain. Diagnosis of the condition depends primarily on clinical features, biochemical parameters and the presence of the Kayser-Fleischer ring, and a new diagnostic scoring system has recently been proposed. Mutations in ATP7B can occur anywhere along the entire 21 exons, which makes the identification of gene defects particularly challenging. Identification of carriers and presymptomatic family members of affected individuals is achieved by polymerase-chain-reaction-based marker analysis. The traditional treatment for WD is based on copper chelation with agents such as D-penicillamine, but use of this drug has been questioned because of reported side effects. The use of agents such as trientine and ammonium tetrathiomolybdate has been advocated, although results of long-term trials are awaited. In selected cases, orthotropic hepatic transplantation can reverse the basic metabolic abnormality in WD and improve both hepatic and neurological symptoms. Studies of the underlying defects in ATP7B and its suspected modifiers ATOX1 and COMMD1 are expected to unravel the disease's genotype-phenotype correlation, and should lead to the design of improved drugs for ameliorating the suffering of patients. Wilson's disease is an inherited disorder leading to accumulation of copper in tissues, mainly in the liver and brain. Genetic defect is in the gene coding ATPase type P (ATP7B). The inheritance is autosomal recessive. Up to now, more then 500 mutations causing Wilson's disease were described. The most frequent mutation in Central Europe is mutation H1069Q. The manifestation of Wilson's disease is usually hepatic or neurologic. Hepatic form is manifested by acute or chronic hepatitis, steatosis or cirrhosis. Neurologic involvement is manifested usually after 20 year of age by motor disturbances (tremor, disturbed speech, problems with writing), which could progress into severe extrapyramidal syndrome with tremor, rigidity, dysartria, dysfagia and muscle contracture. Diagnosis is based on clinical and laboratory examinations (neurologic symptoms, liver disease, low serum ceruloplasmin levels, elevated free copper concentration in serum, high urine copper excretion, and presence of Kayser-Fleischer rings). Confirmation of diagnosis is done by hepatic copper concentration in liver biopsy or by genetic examination. Untreated disease leads to the death of a patient. Treatment is based on chelating agents decreasing the copper content by excretion into urine (D-penicillamine, trientine) or on agents preventing absorption of copper from food (zinc, ammonium-tetrahiomolybdene). Patients with asymptomatic Wilson's disease have to be treated as well. In Czech Republic either penicillamine or zinc are used. Liver transplantation is indicated in patients with fulmit liver failure or decompensated cirrhosis. Screening in families of affected patients (all siblings) is obvious. Wilson's disease (WD), or hepatolenticular degeneration, is an autosomal recessive inheritance disorder of copper metabolism caused by ATP7B gene mutation. As WD is an inherited disease of the nervous system that is not curable; early diagnosis with early and life-long treatment leads to better prognoses. Currently, the recommended treatment for WD is integrated Chinese and Western medicine. A number of studies indicate that treatment of integrative medicine can not only enforce the de-copper effect but also improve liver function, intelligence, and other factors. This article reviewed in detail the advantages of WD treated with Chinese and Western medicine together.
Are transcription and splicing connected?
Yes. There is strong evidence that splicing and transcription are intimately coupled in metazoans, with genome wide surveys show that most splicing occurs during transcription. Chromatin structure, RNA polymerase dynamics, and recruitment of splicing factors through the transcriptional machinery are factors that explain a role for transcription in the regulation of splicing.
Transcription and pre-mRNA splicing are extremely complex multimolecular processes that involve protein-DNA, protein-RNA, and protein-protein interactions. Splicing occurs in the close vicinity of genes and is frequently cotranscriptional. This is consistent with evidence that both processes are coordinated and, in some cases, functionally coupled. This review focuses on the roles of cis- and trans-acting factors that regulate transcription, on constitutive and alternative splicing. We also discuss possible functions in splicing of the C-terminal domain (CTD) of the RNA polymerase II (pol II) largest subunit, whose participation in other key pre-mRNA processing reactions (capping and cleavage/polyadenylation) is well documented. Recent evidence indicates that transcriptional elongation and splicing can be influenced reciprocally: Elongation rates control alternative splicing and splicing factors can, in turn, modulate pol II elongation. The presence of transcription factors in the spliceosome and the existence of proteins, such as the coactivator PGC-1, with dual activities in splicing and transcription can explain the links between both processes and add a new level of complexity to the regulation of gene expression in eukaryotes. Cotranscriptional loading of RNA processing factors onto nascent RNA facilitates efficient gene expression. Mechanisms responsible for coupling transcription and RNA processing are not well defined, but the Saccharomyces cerevisiae TREX complex provides an example. TREX is composed of the subcomplex THO that associates with RNA polymerase II and is required for normal transcriptional elongation. THO associates with proteins involved in RNA splicing and export to form the larger TREX complex. Hence, assembly of TREX physically couples transcriptional elongation with RNA processing factors. Whether metazoan species with long, intron-containing genes utilize a similar mechanism has not been established. Here we show that human hHpr1/p84/Thoc1 associates with elongating RNA polymerase II and the RNA splicing and export factor UAP56 in intact cells. Depletion of hHpr1/p84/Thoc1 causes transcriptional elongation defects and associated cellular phenotypes similar to those observed in THO-deficient yeast. We conclude that hHpr1/p84/Thoc1 regulates transcriptional elongation and may participate in a protein complex functionally analogous to yeast TREX, physically linking elongating RNA polymerase II with RNA processing factors. HIV-1 Tat binds human CyclinT1 and recruits the CDK9/P-TEFb complex to the viral TAR RNA in a step that links RNA polymerase II (RNAPII) C-terminal domain (CTD) Ser 2 phosphorylation with transcription elongation. Previous studies have suggested a connection between Tat and pre-mRNA splicing factors. Here we show that the splicing-associated c-Ski-interacting protein, SKIP, is required for Tat transactivation in vivo and stimulates HIV-1 transcription elongation, but not initiation, in vitro. SKIP associates with CycT1:CDK9/P-TEFb and Tat:P-TEFb complexes in nuclear extracts and interacts with recombit Tat:P-TEFb:TAR RNA complexes in vitro, indicating that it may act through nascent RNA to overcome pausing by RNAPII. SKIP also associates with U5snRNP proteins and tri-snRNP110K in nuclear extracts, and facilitates recognition of an alternative Tat-specific splice site in vivo. The effects of SKIP on transcription elongation, binding to P-TEFb, and splicing are mediated through the SNW domain. HIV-1 Tat transactivation is accompanied by the recruitment of P-TEFb, SKIP, and tri-snRNP110K to the integrated HIV-1 promoter in vivo, whereas the U5snRNPs associate only with the transcribed coding region. These findings suggest that SKIP plays independent roles in transcription elongation and pre-mRNA splicing. Splicing is an important process for regulation of gene expression in eukaryotes, and it has important functional links to other steps of gene expression. Two examples of these linkages include Ceg1, a component of the mRNA capping enzyme, and the chromatin elongation factors Spt4-5, both of which have recently been shown to play a role in the normal splicing of several genes in the yeast Saccharomyces cerevisiae. Using a genomic approach to characterize the roles of Spt4-5 in splicing, we used splicing-sensitive DNA microarrays to identify specific sets of genes that are mis-spliced in ceg1, spt4, and spt5 mutants. In the context of a complex, nested, experimental design featuring 22 dye-swap array hybridizations, comprising both biological and technical replicates, we applied five appropriate statistical models for assessing differential expression between wild-type and the mutants. To refine selection of differential expression genes, we then used a robust model-synthesizing approach, Differential Expression via Distance Synthesis, to integrate all five models. The resultant list of differentially expressed genes was then further analyzed with regard to select attributes: we found that highly transcribed genes with long introns were most sensitive to spt mutations. QPCR confirmation of differential expression was established for the limited number of genes evaluated. In this paper, we showcase splicing array technology, as well as powerful, yet general, statistical methodology for assessing differential expression, in the context of a real, complex experimental design. Our results suggest that the Spt4-Spt5 complex may help coordinate splicing with transcription under conditions that present kinetic challenges to spliceosome assembly or function. Coupling between transcription and RNA processing is a key gene regulatory mechanism. Here we use chromatin immunoprecipitation to detect transcription-dependent accumulation of the precursor mRNA (pre-mRNA) splicing factors hnRNP A1, U2AF65 and U1 and U5 snRNPs on the intron-containing human FOS gene. These factors were poorly detected on intronless heat-shock and histone genes, a result that opposes direct recruitment by RNA polymerase II (Pol II) or the cap-binding complex in vivo. However, an observed RNA-dependent interaction between U2AF65 and active forms of Pol II may stabilize U2AF65 binding to intron-containing nascent RNA. We establish chromatin-RNA immunoprecipitation and show that FOS pre-mRNA is cotranscriptionally spliced. Notably, the topoisomerase I inhibitor camptothecin, which stalls elongating Pol II, increased cotranscriptional splicing factor accumulation and splicing in parallel. This provides direct evidence for a kinetic link between transcription, splicing factor recruitment and splicing catalysis. Recent ChIP experiments indicate that spliceosome assembly and splicing can occur cotranscriptionally in S. cerevisiae. However, only a few genes have been examined, and all have long second exons. To extend these studies, we analyzed intron-containing genes with different second exon lengths by using ChIP as well as whole-genome tiling arrays (ChIP-CHIP). The data indicate that U1 snRNP recruitment is independent of exon length. Recursive splicing constructs, which uncouple U1 recruitment from transcription, suggest that cotranscriptional U1 recruitment contributes to optimal splicing efficiency. In contrast, U2 snRNP recruitment, as well as cotranscriptional splicing, is deficient on short second exon genes. We estimate that > or =90% of endogenous yeast splicing is posttranscriptional, consistent with an analysis of posttranscriptional snRNP-associated pre-mRNA. Alternative splicing of pre-messenger RNA is a key feature of transcriptome expansion in eukaryotic cells, yet its regulation is poorly understood. Spliceosome assembly occurs co-transcriptionally, raising the possibility that DNA structure may directly influence alternative splicing. Supporting such an association, recent reports have identified distinct histone methylation patterns, elevated nucleosome occupancy and enriched DNA methylation at exons relative to introns. Moreover, the rate of transcription elongation has been linked to alternative splicing. Here we provide the first evidence that a DNA-binding protein, CCCTC-binding factor (CTCF), can promote inclusion of weak upstream exons by mediating local RNA polymerase II pausing both in a mammalian model system for alternative splicing, CD45, and genome-wide. We further show that CTCF binding to CD45 exon 5 is inhibited by DNA methylation, leading to reciprocal effects on exon 5 inclusion. These findings provide a mechanistic basis for developmental regulation of splicing outcome through heritable epigenetic marks. To determine the prevalence of cotranscriptional splicing in Drosophila, we sequenced nascent RNA transcripts from Drosophila S2 cells as well as from Drosophila heads. Eighty-seven percent of the introns assayed manifest >50% cotranscriptional splicing. The remaining 13% are cotranscriptionally spliced poorly or slowly, with ∼3% being almost completely retained in nascent pre-mRNA. Although individual introns showed slight but statistically significant differences in splicing efficiency, similar global levels of splicing were seen from both sources. Importantly, introns with low cotranscriptional splicing efficiencies are present in the same primary transcript with efficiently spliced introns, indicating that splicing is intron-specific. The analysis also indicates that cotranscriptional splicing is less efficient for first introns, longer introns, and introns annotated as alternative. Finally, S2 cells expressing the slow RpII215(C4) mutant show substantially less intron retention than wild-type S2 cells. Here we present the development and implementation of a genome-wide reverse genetic screen in the budding yeast, Saccharomyces cerevisiae, that couples high-throughput strain growth, robotic RNA isolation and cDNA synthesis, and quantitative PCR to allow for a robust determination of the level of nearly any cellular RNA in the background of ~5,500 different mutants. As an initial test of this approach, we sought to identify the full complement of factors that impact pre-mRNA splicing. Increasing lines of evidence suggest a relationship between pre-mRNA splicing and other cellular pathways including chromatin remodeling, transcription, and 3' end processing, yet in many cases the specific proteins responsible for functionally connecting these pathways remain unclear. Moreover, it is unclear whether all pathways that are coupled to splicing have been identified. As expected, our approach sensitively detects pre-mRNA accumulation in the vast majority of strains containing mutations in known splicing factors. Remarkably, however, several additional candidates were found to cause increases in pre-mRNA levels similar to that seen for canonical splicing mutants, none of which had previously been implicated in the splicing pathway. Instead, several of these factors have been previously implicated to play roles in chromatin remodeling, 3' end processing, and other novel categories. Further analysis of these factors using splicing-sensitive microarrays confirms that deletion of Bdf1, a factor that links transcription initiation and chromatin remodeling, leads to a global splicing defect, providing evidence for a novel connection between pre-mRNA splicing and this component of the SWR1 complex. By contrast, mutations in 3' end processing factors such as Cft2 and Yth1 also result in pre-mRNA splicing defects, although only for a subset of transcripts, suggesting that spliceosome assembly in S. cerevisiae may more closely resemble mammalian models of exon-definition. More broadly, our work demonstrates the capacity of this approach to identify novel regulators of various cellular RNAs. Alternative splicing has emerged as a key contributor to proteome diversity, highlighting the importance of understanding its regulation. In recent years it became apparent that splicing is predomitly cotranscriptional, allowing for crosstalk between these two nuclear processes. We discuss some of the links between transcription and splicing, with special emphasis on the role played by transcription elongation in the regulation of alternative splicing events and in particular the kinetic model of alternative splicing regulation. This article is part of a Special Issue entitled: RNA polymerase II Transcript Elongation. Splicing and alternative splicing are involved in the expression of most human genes, playing key roles in differentiation, cell cycle progression, and development. Misregulation of splicing is frequently associated to disease, which imposes a better understanding of the mechanisms underlying splicing regulation. Accumulated evidence suggests that multiple trans-acting factors and cis-regulatory elements act together to determine tissue-specific splicing patterns. Besides, as splicing is often cotranscriptional, a complex picture emerges in which splicing regulation not only depends on the balance of splicing factor binding to their pre-mRNA target sites but also on transcription-associated features such as protein recruitment to the transcribing machinery and elongation kinetics. Adding more complexity to the splicing regulation network, recent evidence shows that chromatin structure is another layer of regulation that may act through various mechanisms. These span from regulation of RNA polymerase II elongation, which ultimately determines splicing decisions, to splicing factor recruitment by specific histone marks. Chromatin may not only be involved in alternative splicing regulation but in constitutive exon recognition as well. Moreover, splicing was found to be necessary for the proper 'writing' of particular chromatin signatures, giving further mechanistic support to functional interconnections between splicing, transcription and chromatin structure. These links between chromatin configuration and splicing raise the intriguing possibility of the existence of a memory for splicing patterns to be inherited through epigenetic modifications. Spliceosome assembly and/or splicing of a nascent transcript may be crucial for proper isoform expression and gene regulation in higher eukaryotes. We recently showed that cotranscriptional splicing occurs efficiently in Drosophila, but there are not comparable genome-wide nascent splicing data from mammals. To provide this comparison, we analyze a recently generated, high-throughput sequencing data set of mouse liver nascent RNA, originally studied for circadian transcriptional regulation. Cotranscriptional splicing is approximately twofold less efficient in mouse liver than in Drosophila, i.e., nascent intron levels relative to exon levels are ∼0.55 in mouse versus 0.25 in the fly. An additional difference between species is that only mouse cotranscriptional splicing is optimal when 5'-exon length is between 50 and 500 bp, and intron length does not correlate with splicing efficiency, consistent with exon definition. A similar analysis of intron and exon length dependence in the fly is more consistent with intron definition. Contrasted with these differences are many similarities between the two systems: Alternatively annotated introns are less efficiently spliced cotranscriptionally than constitutive introns, and introns of single-intron genes are less efficiently spliced than introns from multi-intron genes. The most striking common feature is intron position: Cotranscriptional splicing is much more efficient when introns are far from the 3' ends of their genes. Additionally, absolute gene length correlates positively with cotranscriptional splicing efficiency independently of intron location and position, in flies as well as in mice. The gene length and distance effects indicate that more "nascent time" gives rise to greater cotranscriptional splicing efficiency in both systems. Eukaryotic gene expression involves tight coordination between transcription and pre-mRNA splicing; however, factors responsible for this coordination remain incompletely defined. Here, we explored the genetic, functional, and biochemical interactions of a likely coordinator, Npl3, an SR-like protein in Saccharomyces cerevisiae that we recently showed is required for efficient co-transcriptional recruitment of the splicing machinery. We surveyed the NPL3 genetic interaction space and observed a significant enrichment for genes involved in histone modification and chromatin remodeling. Specifically, we found that Npl3 genetically interacts with both Bre1, which mono-ubiquitinates histone H2B as part of the RAD6 Complex, and Ubp8, the de-ubiquitinase of the SAGA Complex. In support of these genetic data, we show that Bre1 physically interacts with Npl3 in an RNA-independent manner. Furthermore, using a genome-wide splicing microarray, we found that the known splicing defect of a strain lacking Npl3 is exacerbated by deletion of BRE1 or UBP8, a phenomenon phenocopied by a point mutation in H2B that abrogates ubiquitination. Intriguingly, even in the presence of wild-type NPL3, deletion of BRE1 exhibits a mild splicing defect and elicits a growth defect in combination with deletions of early and late splicing factors. Taken together, our data reveal a connection between Npl3 and an extensive array of chromatin factors and describe an uticipated functional link between histone H2B ubiquitination and pre-mRNA splicing.
What is the mode of inheritance of Facioscapulohumeral muscular dystrophy (FSHD)?
Facioscapulohumeral muscular dystrophy has an autosomal dominant inheritance pattern.
Extrapolating the figures from a previous study on FSHD in a province of The Netherlands to the entire Dutch population suggests that at present a nearly complete overview is obtained of all symptomatic kindred. In 139 families, domit inheritance was observed in 97, a pattern compatible with germline mosaicism in 6, while sporadic cases were found in 36 families. A mutation frequency of 9.6% was calculated. Mental retardation and severe retinal vasculopathy were reported in low frequencies (1%). Early onset was seen more frequently in sporadic cases. Chromosome 4 linkage appeared excluded in 3 of 22 autosomal-domit families. The clinical pictures in the linked and nonlinked families were identical. Facioscapulohumeral dystrophy (FSHD) is an autosomal-domit muscular disorder associated with a short (<35 kb) EcoRI/BlnI fragment resulting from deletion of an integral number of units of a 3.3-kb repeat located at 4q35. In this study, we determined fragment sizes separated by pulsed-field gel electrophoresis in a patient with an apparently sporadic case of FSHD and in his healthy family members. A 38-kb fragment was detected in the proband, in his older brother, and in their father. This finding prompted a clinical reevaluation of the father and brother. A subclinical phenotype restricted to abdominal muscle weakness was detected, and serum creatine kinase values were found to be elevated in both. The proband's brother also showed evidence of an independently occurring subtelomeric rearrangement of 4q35, which normally occurs in about 20% of the population. The identification of a "borderline" 38-kb EcoRI/BlnI fragment in an affected subject and his very mildly affected relatives extends the size range of disease alleles and expands existing data on the variable intrafamilial expressivity of FSHD. This study highlights the importance of a careful molecular and clinical analysis extended to family members of apparently sporadic cases with larger EcoRI/BlnI fragments for accurate diagnosis and appropriate genetic counseling in FSHD. Facioscapulohumeral muscular dystrophy (FSHD) is a slowly progressive myopathy with autosomal domit inheritance remarkable for its early involvement of facial musculature. The purpose of our study was to assess the rate of strength deterioration, functional condition and performance of activity of daily living of patients with FSHD in Taiwan. Twenty patients diagnosed with FSHD were included in this study. Manual muscle testing (MMT) was used to evaluate muscle strength. The Brooke and Vignos scales were used to assess upper and lower extremity function respectively, and the capability of the activity of daily living was measured by Barthel index. The result of the strength testing was characterized by the presence of a progressive asymmetrical muscular weakness in patients with FSHD. The mean muscular strength of the right extremity was weaker than its left counterparts (p < 0.05) and the shoulder muscle group was the weakest. According to the Brooke functional scale, 20% of our patients were graded as 1, 30% as grade 2, and 50% as grade 3. On the Vignos functional scale, 50% of patients fell into grade 1, 10% in grade 2, and 40% in grades 3-5. Vignos scale was significantly correlated with mean muscle strength (p < 0.05). The average value of Barthel index was 97.8 +/- 4.7. The muscle strength decline in this Taiwanese of FSHD population was more severe in shoulder girdle area. The mean muscle strength of the right extremity was weaker than the left. Most of our patients suffered from mild or moderate physical disability. Finding of these Taiwanese FSHD population is similar to those reported elsewhere in the world. A 60-year-old man diagnosed clinically with Becker's muscular dystrophy 20 years ago by another physician presented with gradually progressive proximal muscle weakness since teenage years. Family history revealed a strong paternal familial inheritance pattern of similar distribution of weakness-face, forearm flexion, knee extension and foot dorsiflexion. Work-ups revealed B12 deficiency and allele 1 deletion in fascioscapulohumeral muscular dystrophy (FSHD) DNA testing. FSHD is the third most common muscular dystrophy. Clinical diagnosis is made from the distinctive pattern of weakness, autosomal-domit inheritance, and confirmed by genetic testing. This case strongly demonstrates the importance of a thorough and careful clinical evaluation even in a case with a long standing diagnosis. Facioscapulohumeral muscular dystrophy (FSHD) is a neuromuscular disease, characterized by an autosomal domit mode of inheritance, facial involvement, and selectivity and asymmetry of muscle involvement. In general, FSHD typically presents before age 20 years. Usually, FSHD muscle involvement starts in the face and then progresses to the shoulder girdle, the humeral muscles and the abdominal muscles, and then the anterolateral compartment of the leg. Disease severity is highly variable and progression is very slow. About 20% of FSHD patients become wheelchair-bound. Lifespan is not shortened. The diagnosis of FSHD is based on a genetic test by which a deletion of 3.3kb DNA repeats (named D4Z4 and mapping to the subtelomeric region of chromosome 4q35) is identified. The progressive pattern of FSHD requires that the severity of symptoms as well as their physical, social and psychological impact be evaluated on a regular basis. A yearly assessment is recommended. Multidisciplinary management of FSHD--consisting of a combination of genetic counselling, functional assessment, an assessment by a physical therapist, prescription of symptomatic therapies and prevention of known complications of this disease--is required. Prescription of physical therapy sessions and orthopedic appliances are to be adapted to the patient's deficiencies and contractures. Facioscapulohumeral dystrophy (FSHD) is characterized by chromatin relaxation of the D4Z4 macrosatellite array on chromosome 4 and expression of the D4Z4-encoded DUX4 gene in skeletal muscle. The more common form, autosomal domit FSHD1, is caused by contraction of the D4Z4 array, whereas the genetic determits and inheritance of D4Z4 array contraction-independent FSHD2 are unclear. Here, we show that mutations in SMCHD1 (encoding structural maintece of chromosomes flexible hinge domain containing 1) on chromosome 18 reduce SMCHD1 protein levels and segregate with genome-wide D4Z4 CpG hypomethylation in human kindreds. FSHD2 occurs in individuals who inherited both the SMCHD1 mutation and a normal-sized D4Z4 array on a chromosome 4 haplotype permissive for DUX4 expression. Reducing SMCHD1 levels in skeletal muscle results in D4Z4 contraction-independent DUX4 expression. Our study identifies SMCHD1 as an epigenetic modifier of the D4Z4 metastable epiallele and as a causal genetic determit of FSHD2 and possibly other human diseases subject to epigenetic regulation.
Is Alu hypomethylation associated with breast cancer?
Yes, Alu elements were found to be hypomethylated in breast cancer, especially in the HER2-enriched subtype. Furthermore, Alu hypomethylation was identified as a late event during breast cancer progression, and in invasive breast cancer, tended to be associated with negative estrogen receptor status and poor disease-free survival of the patients.
The changes in DNA methylation status in cancer cells are characterized by hypermethylation of promoter CpG islands and diffuse genomic hypomethylation. Alu and long interspersed nucleotide element-1 (LINE-1) are non-coding genomic repetitive sequences and methylation of these elements can be used as a surrogate marker for genome-wide methylation status. This study was designed to evaluate the changes of Alu and LINE-1 hypomethylation during breast cancer progression from normal to pre-invasive lesions and invasive breast cancer (IBC), and their relationship with characteristics of IBC. We analyzed the methylation status of Alu and LINE-1 in 145 cases of breast samples including normal breast tissue, atypical ductal hyperplasia/flat epithelial atypia (ADH/FEA), ductal carcinoma in situ (DCIS) and IBC, and another set of 129 cases of IBC by pyrosequencing. Alu methylation showed no significant changes during multistep progression of breast cancer, although it tended to decrease during the transition from DCIS to IBC. In contrast, LINE-1 methylation significantly decreased from normal to ADH/FEA, while it was similar in ADH/FEA, DCIS and IBC. In IBC, Alu hypomethylation correlated with negative estrogen receptor (ER) status, and LINE-1 hypomethylation was associated with negative ER status, ERBB2 (HER2) amplification and p53 overexpression. Alu and LINE-1 methylation status was significantly different between breast cancer subtypes, and the HER2 enriched subtype had lowest methylation levels. In survival analyses, low Alu methylation status tended to be associated with poor disease-free survival of the patients. Our findings suggest that LINE-1 hypomethylation is an early event and Alu hypomethylation is probably a late event during breast cancer progression, and prominent hypomethylation of Alu and LINE-1 in HER2 enriched subtype may be related to chromosomal instability of this specific subtype.
Which proteins participate in the formation of the ryanodine receptor quaternary macromolecular complex?
Junctin is a major transmembrane protein in cardiac junctional sarcoplasmic reticulum, which forms a quaternary complex with the ryanodine receptor (Ca(2+) release channel), triadin, and calsequestrin.
Triadin 1 is a major transmembrane protein in cardiac junctional sarcoplasmic reticulum (SR), which forms a quaternary complex with the ryanodine receptor (Ca(2+) release channel), junctin, and calsequestrin. To better understand the role of triadin 1 in excitation-contraction coupling in the heart, we generated transgenic mice with targeted overexpression of triadin 1 to mouse atrium and ventricle, employing the alpha-myosin heavy chain promoter to drive protein expression. The protein was overexpressed 5-fold in mouse ventricles, and overexpression was accompanied by cardiac hypertrophy. The levels of two other junctional SR proteins, the ryanodine receptor and junctin, were reduced by 55% and 73%, respectively, in association with triadin 1 overexpression, whereas the levels of calsequestrin, the Ca(2+)-binding protein of junctional SR, and of phospholamban and SERCA2a, Ca(2+)-handling proteins of the free SR, were unchanged. Cardiac myocytes from triadin 1-overexpressing mice exhibited depressed contractility; Ca(2+) transients decayed at a slower rate, and cell shortening and relengthening were diminished. The extent of depression of cell shortening of triadin 1-overexpressing cardiomyocytes was rate-dependent, being more depressed under low stimulation frequencies (0.5 Hz), but reaching comparable levels at higher frequencies of stimulation (5 Hz). Spontaneously beating, isolated work-performing heart preparations overexpressing triadin 1 also relaxed at a slower rate than control hearts, and failed to adapt to increased afterload appropriately. The fast time inactivation constant, tau(1), of the l-type Ca(2+) channel was prolonged in transgenic cardiomyocytes. Our results provide evidence for the coordinated regulation of junctional SR protein expression in heart independent of free SR protein expression, and furthermore suggest an important role for triadin 1 in regulating the contractile properties of the heart during excitation-contraction coupling. OBJECTIVE: Junctin is a major transmembrane protein in cardiac junctional sarcoplasmic reticulum, which forms a quaternary complex with the ryanodine receptor (Ca(2+) release channel), triadin, and calsequestrin. METHODS: To better understand the role of junctin in excitation-contraction coupling in the heart, we generated transgenic mice with targeted overexpression of junctin to mouse heart, using the alpha-MHC promoter to drive protein expression. RESULTS: The protein was overexpressed 10-fold in mouse ventricles and overexpression was accompanied by cardiac hypertrophy (19%). The levels of two other junctional SR-proteins, the ryanodine receptor and triadin, were reduced by 32% and 23%, respectively. However, [3H]ryanodine binding and the expression levels of calsequestrin, phospholamban and SERCA2a remained unchanged. Cardiomyocytes from junctin-overexpressing mice exhibited impaired relaxation: Ca(2+) transients decayed at a slower rate and cell relengthening was prolonged. Isolated electrically stimulated papillary muscles from junctin-overexpressing hearts exhibited prolonged mechanical relaxation, and echocardiographic parameters of relaxation were prolonged in the living transgenic mice. The amplitude of caffeine-induced Ca(2+) transients was lower in cardiomyocytes from junctin-overexpressing mice. The inactivation kinetics of L-type Ca(2+) channel were prolonged in junctin-overexpressing cardiomyocytes using Ca(2+) or Ba(2+) as charge carriers. CONCLUSION: Our data provide evidence that cardiac-specific overexpression of junctin is accompanied by impaired myocardial relaxation with prolonged Ca(2+) transient kinetics on the cardiomyocyte level. In mammalian striated muscles, ryanodine receptor (RyR), triadin, junctin, and calsequestrin form a quaternary complex in the lumen of sarcoplasmic reticulum. Such intermolecular interactions contribute not only to the passive buffering of sarcoplasmic reticulum luminal Ca2+, but also to the active Ca2+ release process during excitation-contraction coupling. Here we tested the hypothesis that specific charged amino acids within the luminal portion of RyR mediate its direct interaction with triadin. Using in vitro binding assay and site-directed mutagenesis, we found that the second intraluminal loop of the skeletal muscle RyR1 (amino acids 4860-4917), but not the first intraluminal loop of RyR1 (amino acids 4581-4640) could bind triadin. Specifically, three negatively charged residues Asp4878, Asp4907, and Glu4908 appear to be critical for the association with triadin. Using deletional approaches, we showed that a KEKE motif of triadin (amino acids 200-232) is essential for the binding to RyR1. Because the second intraluminal loop of RyR has been previously shown to contain the ion-conducting pore as well as the selectivity filter of the Ca2+ release channel, and Asp4878, Asp4907, and Glu4908 residues are predicted to locate at the periphery of the pore assembly of the channel, our data suggest that a physical interaction between RyR1 and triadin could play an active role in the overall Ca2+ release process of excitation-contraction coupling in muscle cells. Junctin is a transmembrane protein of the cardiac junctional sarcoplasmic reticulum (SR) that binds to the ryanodine receptor, calsequestrin, and triadin 1. This quaternary protein complex is thought to facilitate SR Ca2+ release. To improve our understanding of the contribution of junctin to the regulation of SR function, we examined the age-dependent effects of junctin overexpression in the atrium of 3-, 6-, and 18-wk-old transgenic mice. The ratio of atrial weight and body weight was unchanged between junctin-overexpressing (JCN) and wild-type (WT) mice at all ages investigated (n=6-8). The protein expression of triadin 1 was decreased starting in 3-wk-old JCN atria (by 69%), whereas the expression of the ryanodine receptor was diminished in 6- (by 48%) and 18-wk-old (by 57%) JCN atria compared with age-matched WT atria. Force of contraction was decreased by 35% in 18-wk-old JCN compared with age-matched WT left atrial muscle strips, which was accompanied by a prolonged time of relaxation (48.1 +/- 0.9 vs. 44.2 +/- 0.8 ms, respectively, n=6-8, P <0.05). The spontaneous beating rate of isolated right atria was higher in 18-wk-old JCN mice compared with age-matched WT mice (389 +/- 10 vs. 357 +/- 6 beats/min, respectively, n=6-8, P <0.05). Heart rate was lower by 9% in telemetric ECG recordings in 18-wk-old JCN mice during stress tests. Three-week-old JCN atria exhibited a higher potentiation of force of contraction at rest pauses of 30 s (by 13%) and of 300 s (by 35%), suggesting increased SR Ca2+ content. This was consistent with the higher force of contraction in 3-wk-old JCN atria (by 29%) compared with age-matched WT atria (by 10%) under the administration of caffeine. We conclude that in 3-wk-old atria, junctin overexpression was associated with a reduced expression of triadin 1 resulting in a higher SR Ca2+ load without changes in contractility or heart rate. In 6-wk-old JCN atria, the compensatory downregulation of the ryanodine receptor may offset the effects of junctin overexpression. Finally, the progressive decrease in ryanodine receptor density may contribute to the decreased atrial contractility and lower heart rate during stress in 18-wk-old JCN mice. Calsequestrin, the major calcium sequestering protein in the sarcoplasmic reticulum of muscle, forms a quaternary complex with the ryanodine receptor calcium release channel and the intrinsic membrane proteins triadin and junctin. We have investigated the possibility that calsequestrin is a luminal calcium concentration sensor for the ryanodine receptor. We measured the luminal calcium concentration at which calsequestrin dissociates from the ryanodine receptor and the effect of calsequestrin on the response of the ryanodine receptor to changes in luminal calcium. We provide electrophysiological and biochemical evidence that: 1), luminal calcium concentration of >/=4 mM dissociates calsequestrin from junctional face membrane, whereas in the range of 1-3 mM calsequestrin remains attached; 2), the association with calsequestrin inhibits ryanodine receptor activity, but amplifies its response to changes in luminal calcium concentration; and 3), under physiological calcium conditions (1 mM), phosphorylation of calsequestrin does not alter its ability to inhibit native ryanodine receptor activity when the anchoring proteins triadin and junctin are present. These data suggest that the quaternary complex is intact in vivo, and provides further evidence that calsequestrin is involved in the sarcoplasmic reticulum calcium signaling pathway and has a role as a luminal calcium sensor for the ryanodine receptor. In cardiac muscle, junctin forms a quaternary protein complex with the ryanodine receptor (RyR), calsequestrin, and triadin 1 at the luminal face of the junctional sarcoplasmic reticulum (jSR). By binding directly the RyR and calsequestrin, junctin may mediate the Ca(2+)-dependent regulatory interactions between both proteins. To gain more insight into the underlying mechanisms of impaired contractile relaxation in transgenic mice with cardiac-specific overexpression of junctin (TG), we studied cellular Ca(2+) handling in these mice. We found that the SR Ca(2+) load was reduced by 22% in cardiomyocytes from TG mice. Consistent with this, the frequency of Ca(2+) sparks was diminished by 32%. The decay of spontaneous Ca(2+) sparks was prolonged by 117% in TG. This finding was associated with a lower Na(+)-Ca(2+) exchanger (NCX) protein expression (by 67%) and a higher basal RyR phosphorylation at Ser(2809) (by 64%) in TG. The shortening- and Delta[Ca](i)-frequency relationships (0.5-4 Hz) were flat in TG compared to wild-type (WT) which exhibited a positive staircase for both parameters. Furthermore, increasing stimulation frequencies hastened the time of relaxation and the decay of [Ca](i) by a higher percentage in TG. We conclude that the impaired relaxation in TG may result from a reduced NCX expression and/or a higher SR Ca(2+) leak. The altered shortening-frequency relationship in TG seems to be a consequence of an impaired excitation-contraction coupling with depressed SR Ca(2+) release at higher rates of stimulation. Our data suggest that the more prominent frequency-dependent hastening of relaxation in TG results from a stimulation of SR Ca(2+) transport reflected by corresponding changes of [Ca](i). Triadin and junctin are integral sarcoplasmic reticulum membrane proteins that form a macromolecular complex with the skeletal muscle ryanodine receptor (RyR1) but their roles in skeletal muscle calcium homeostasis remain incompletely understood. Here we report that delivery of siRNAs specific for triadin or junctin into C2C12 skeletal myoblasts reduced the expression of triadin and junctin in 8-day-old myotubes by 80 and 100%, respectively. Knocking down either triadin or junctin in these cells reduced Ca2+ release induced by depolarization (10mM KCl) by 20-25%. Unlike triadin knockdown myotubes, junctin knockdown and junctin/triadin double knockdown myotubes also had reduced Ca2+ release induced by 400 microM 4-chloro-m-cresol, 10mM caffeine, 400 microM UTP, or 1 microM thapsigargin. Thus, knocking down junctin compromised the Ca2+ stores in the sarcoplasmic reticulum of these cells. Our subsequent studies showed that in junctin knockdown myotubes at least two sarcoplasmic reticulum proteins (RyR1 and skeletal muscle calsequestrin) were down-regulated while these proteins' mRNA expression was not affected. The results suggest that triadin has a role in facilitating KCl depolarization-induced Ca2+ release in contrast to junctin which has a role in maintaining sarcoplasmic reticulum Ca2+ store size in C2C12 myotubes. Junctin, a 26 kDa intra-sarcoplasmic reticulum (SR) protein, forms a quaternary complex with triadin, calsequestrin and the ryanodine receptor (RyR) at the junctional SR membrane. The physiological role for junctin in the luminal regulation of RyR Ca(2+) release remains unresolved, but it appears to be essential for proper cardiac function since ablation of junctin results in increased ventricular automaticity. Given that the junctin levels are severely reduced in human failing hearts, we performed an in-depth study of the mechanisms affecting intracellular Ca(2+) homeostasis in junctin-deficient cardiomyocytes. In concurrence with sparks, JCN-KO cardiomyocytes display increased Ca(2+) transient amplitude, resulting from increased SR [Ca(2+)] ([Ca(2+)](SR)). Junctin ablation appears to affect how RyRs 'sense' SR Ca(2+) load, resulting in decreased diastolic SR Ca(2+) leak despite an elevated [Ca(2+)](SR). Surprisingly, the β-adrenergic enhancement of [Ca(2+)](SR) reverses the decrease in RyR activity and leads to spontaneous Ca(2+) release, evidenced by the development of spontaneous aftercontractions. Single channel recordings of RyRs from WT and JCN-KO cardiac SR indicate that the absence of junctin produces a dual effect on the normally linear response of RyRs to luminal [Ca(2+)]: at low luminal [Ca(2+)] (<1 mmol l(-1)), junctin-devoid RyR channels are less responsive to luminal [Ca(2+)]; conversely, high luminal [Ca(2+)] turns them hypersensitive to this form of channel modulation. Thus, junctin produces complex effects on Ca(2+) sparks, transients, and leak, but the luminal [Ca(2+)]-dependent dual response of junctin-devoid RyRs demonstrates that junctin normally acts as an activator of RyR channels at low luminal [Ca(2+)], and as an inhibitor at high luminal [Ca(2+)]. Because the crossover occurs at a [Ca(2+)](SR) that is close to that present in resting cells, it is possible that the activator-inhibitor role of junctin may be exerted under periods of prevalent parasympathetic and sympathetic activity, respectively. RATIONALE: Catecholaminergic polymorphic ventricular tachycardia is an inherited disease that predisposes to cardiac arrest and sudden death. The disease is associated with mutations in the genes encoding for the cardiac ryanodine receptor (RyR2) and cardiac calsequestrin (CASQ2). CASQ2 mutations lead to a major loss of CASQ2 monomers, possibly because of enhanced degradation of the mutant protein. The decrease of CASQ2 is associated with a reduction in the levels of Triadin (TrD) and Junctin (JnC), two proteins that form, with CASQ2 and RyR2, a macromolecular complex devoted to control of calcium release from the sarcoplasmic reticulum. OBJECTIVE: We intended to evaluate whether viral gene transfer of wild-type CASQ2 may rescue the broad spectrum of abnormalities caused by mutant CASQ2. METHODS AND RESULTS: We used an adeno-associated serotype 9 viral vector to express a green fluorescent protein-tagged CASQ2 construct. Twenty weeks after intraperitoneal injection of the vector in neonate CASQ2 KO mice, we observed normalization of the levels of calsequestrin, triadin, and junctin, rescue of electrophysiological and ultrastructural abnormalities caused by CASQ2 ablation, and lack of life-threatening arrhythmias. CONCLUSIONS: We have proven the concept that induction of CASQ2 expression in knockout mice reverts the molecular, structural, and electric abnormalities and prevents life-threatening arrhythmias in CASQ2-defective catecholaminergic polymorphic ventricular tachycardia mice. These data support the view that development of CASQ2 viral gene transfer could have clinical application. Calsequestrin (CSQ) is a Ca(2+) storage protein that interacts with triadin (TRN), the ryanodine receptor (RyR), and junctin (JUN) to form a macromolecular tetrameric Ca(2+) signaling complex in the cardiac junctional sarcoplasmic reticulum (SR). Heart-specific overexpression of CSQ in transgenic mice (TG(CSQ)) was associated with heart failure, attenuation of SR Ca(2+) release, and downregulation of associated junctional SR proteins, e.g., TRN. Hence, we tested whether co-overexpression of CSQ and TRN in mouse hearts (TG(CxT)) could be beneficial for impaired intracellular Ca(2+) signaling and contractile function. Indeed, the depressed intracellular Ca(2+) concentration ([Ca](i)) peak amplitude in TG(CSQ) was normalized by co-overexpression in TG(CxT) myocytes. This effect was associated with changes in the expression of cardiac Ca(2+) regulatory proteins. For example, the protein level of the L-type Ca(2+) channel Ca(v)1.2 was higher in TG(CxT) compared with TG(CSQ). Sarco(endo)plasmic reticulum Ca(2+)-ATPase 2a (SERCA2a) expression was reduced in TG(CxT) compared with TG(CSQ), whereas JUN expression and [(3)H]ryanodine binding were lower in both TG(CxT) and TG(CSQ) compared with wild-type hearts. As a result of these expressional changes, the SR Ca(2+) load was higher in both TG(CxT) and TG(CSQ) myocytes. In contrast to the improved cellular Ca(2+), transient co-overexpression of CSQ and TRN resulted in a reduced survival rate, an increased cardiac fibrosis, and a decreased basal contractility in catheterized mice, working heart preparations, and isolated myocytes. Echocardiographic and hemodynamic measurements revealed a depressed cardiac performance after isoproterenol application in TG(CxT) compared with TG(CSQ). Our results suggest that co-overexpression of CSQ and TRN led to a normalization of the SR Ca(2+) release compared with TG(CSQ) mice but a depressed contractile function and survival rate probably due to cardiac fibrosis, a lower SERCA2a expression, and a blunted response to β-adrenergic stimulation. Thus the TRN-to-CSQ ratio is a critical modulator of the SR Ca(2+) signaling.
What kind of chromatography is HILIC?
Hydrophilic Interaction Chromatography (HILIC)
Uric acid is the end-product of purine metabolism and a major antioxidant in humans. The concentrations of uric acid in plasma and urine are associated with various diseases and routinely measured in clinical and biomedical laboratories using enzymatic conversion and colorimetric measurement. In this study a hydrophilic interaction chromatographic (HILIC) method was developed for simultaneous determination of uric acid and creatinine, a biomarker of urine dilution and renal function, in human urine. Urine samples were pretreated by dilution, protein precipitation, centrifugation and filtration. Uric acid and creatinine were separated from other components in urine samples and quantified using HILIC chromatography. A linear relationship between the ratio of the peak area of the standards to that of the internal standard and the concentration of the standards was obtained for both uric acid and creatinine with the square of correlation coefficients >0.999 for both analytes. The detection limits were 0.04 μg/mL for creatinine and 0.06 μg/mL for uric acid. The described HILIC method has proved to be simple, accurate, robust and reliable. For the analysis of highly hydrophilic and polar compounds, Hydrophilic Interaction Chromatography (HILIC) has been established as a valuable complementary approach to reversed-phase liquid chromatography (RPLC). Moreover, the use of mobile phases with a high percentage of organic solvent in HILIC separation is beneficial for mass spectrometric (MS) detection, because of enhanced ionization which results in an increased sensitivity. In this review, various applications of HILIC are described for a number of environmental and food contamits together with detailed methodological descriptions and the advantages or drawbacks of HILIC compared to other LC methods are critically discussed. In the first part of the review, an overview is given of the work that has been carried out with HILIC for the analysis of pharmaceuticals and pesticides in environmental samples. HILIC has shown its applicability for polar pharmaceuticals, such as antibiotics, estrogens and their metabolites, drugs of abuse, cytostatics, metformin and contrast agents. In the pesticide group, HILIC chromatography was helpful for polar phenylurea and organophosphorus pesticides. The second part of the review focuses on the analysis of antibiotic residues in food and feed with HILIC, while in the pesticide group, HILIC experiments have been reported for dithiocarbamates and quaternary ammonium compounds. The last chapter gives an overview of the analysis by HILIC of miscellaneous analytes in aquatic and food/feed samples. BACKGROUND: In bioanalysis, phospholipids may affect the precision and accuracy of LC-MS/MS methods and compromise the quality of the results, especially when samples in complex biomatrices are extracted by protein precipitation techniques. RESULTS: It was found that the retentive behavior of both common pharmaceuticals and physiologically relevant phospholipids under bare silica hydrophilic-interaction LC (HILIC) is more predictable than under reversed-phase conditions. In particular, the retention time of phospholipids was not significantly affected by varying the salt and acid modifiers in the mobile phases, but common pharmaceuticals can be shifted away from these phospholipid interferences through mobile phase modifiers. Several mass spectrometric techniques were applied to confirm this finding. CONCLUSION: HILIC chromatography is a valued tool in the development of robust bioanalytical assays with minimal and predictable phospholipid interferences. Furthermore, addition of a small amount of ion-pairing additives can reliably move pharmaceutical compounds away from these suppressive regions. Hydrophilic-interaction liquid chromatography (HILIC) is a widely used technique for small polar molecule analysis and offers the advantage of improved sensitivity in mass spectrometry. Although HILIC is today frequently employed as an orthogonal fractionation method for peptides during the proteomic discovery phase, it is still seldom considered for quantification. In this study, the performances in terms of peak capacity and sensitivity of 3 HILIC columns were compared to traditional reversed phase liquid C(18) column in the context of targeted quantification of proteotypic peptides using selected reaction monitoring mode (SRM). The results showed that the maximum sensitivity in HILIC chromatography was achieved by using an amide column without salt buffer and that the signal increased compared to classic reversed phase chromatography. However, the intensity improvement is quite low compared to the one obtained for small molecules. This is due on one hand to a higher matrix effect in HILIC and on the other hand to a change of charge states of peptides in organic solvent (doubly charged to monocharged). The doubly charged ions can be more readily dissociated than singly charged ions, making them ideal for SRM peptide quantification. As a result "supercharging" reagents are added to the mobile phase to shift from predomit singly charged ions to the more favorable doubly charged species. Using such optimized conditions, peptide signal is improved by a factor of between two and ten for 88% of the peptides of the 81 peptides investigated. A hydrophilic interaction liquid chromatography-tandem mass spectrometry (HILIC LC-MS/MS) method was developed and validated to simultaneously quantify six aqueous choline-related compounds and eight major phospholipids classes in a single run. HILIC chromatography was coupled to positive ion electrospray mass spectrometry. A combination of multiple scan modes including precursor ion scan, neutral loss scan and multiple reaction monitoring was optimized for the determination of each compound or class in a single LC/MS run. This work developed a simplified extraction scheme in which both free choline and related compounds along with phospholipids were extracted into a homogenized phase using chloroform/methanol/water (1:2:0.8) and diluted into methanol for the analysis of target compounds in a variety of sample matrices. The analyte recoveries were evaluated by spiking tissues and food samples with two isotope-labeled internal standards, PC-d(3) and Cho-d(3). Recoveries of between 90% and 115% were obtained by spiking a range of sample matrices with authentic standards containing all 14 of the target analytes. The precision of the analysis ranged from 1.6% to 13%. Accuracy and precision was comparable to that obtained by quantification of selected phospholipid classes using (31)P NMR. A variety of sample matrices including egg yolks, human diets and animal tissues were analyzed using the validated method. The measurements of total choline in selected foods were found to be in good agreement with values obtained from the USDA choline database.
What is the effect of TRH on myocardial contractility?
TRH improves myocardial contractility
Thyrotropin-releasing hormone (TRH) improved mean arterial pressure (MAP) and myocardial contractility (dp/dtmax, -dp/dtmax, Vpm, and Vmax) and increased plasma epinephrine levels significantly at 10 min after TRH treatment in rabbits following shock, but the effects of TRH on MAP and myocardial contractility disappeared in reserpinized rabbits (4 mg/kg, 24 hr pre-treatment, iv). TRH had no effect on myocardial contractility and MAP at 20 and 30 min post-treatment in rabbits pre-treated with the beta adrenergic blocker propranolol (1 mg/kg, 1 hr before TRH treatment, iv), but the alpha adrenergic blocker phenoxybenzamine did not affect these responses to TRH. Experiments in vitro show that although TRH (10(-3) to 10(-8) M) had no direct effects on the isolated heart, left atrium, and aortic strip, it did potentiate the inotropic effects of isoprenaline and dopamine on the left atrium. These results suggest that the antishock effects of TRH are related to adrenergic systems, perhaps acting on the sympathomedullary system to secrete epinephrine and sensitize the beta receptors, but not alpha receptors. Thus, TRH improves cardiac contractility, cardiac output, and hemodynamics during hemorrhagic shock. The sensitization of the beta adrenergic and dopamine receptors may play an important role in the direct peripheral cardiovascular mechanism of TRH effects. Thyrotropin-releasing hormone (TRH) could improve mean arterial pressure (MAP), myocardial contractile parameters (+/- dp/dtmax, Vpm and Vmax) and increase plasma epinephrine level significantly at 10 min after TRH administration in hemorrhagic shock rabbits, but the action of TRH on MAP and the myocardial contractility did not appear in rabbits pre-treated with reserpine (4 mg/kg, 24 h pre-treatment, i.v.). TRH had no effects on myocardial contractility and MAP at 20 and 30 min after administration to rabbits pre-treated with beta-adrenergic blocker propranolol (1 mg/kg, 1 h before TRH injection i.v.), but it did exert effects on these parameters in rabbits pre-treated with alpha-adrenergic blocker phenoxybenzamine. Experiments in vitro showed that, although TRH (10(-4) M/L) had no direct effect on heart, left atrium and aortic strip, it did potentiate the inotropic effects of isoprenaline and dopamine on the left atrium. These results suggested that antishock effect of TRH is related to adrenergic system. TRH stimulates sympathomedullary system to secrete epinephrine and sensitize the beta-receptors, but not alpha-receptors. Thus, TRH improves cardiac contractility, cardiac output and hemodynamics during hemorrhagic shock. The sensitization of the beta- and dopamine receptors played an important role in producing direct peripheral actions of TRH. The effects of thyrotropin releasing hormone (TRH) on the contractility of electrically stimulated and perfused isolated rat hearts were investigated. TRH in the range of 0.1-10 mumol/l was found to exert a positive inotropic effect on cardiac contractility, which however qualitatively differed at lower vs. higher concentrations of the hormone: at 1 mumol/l, TRH was found to significantly enhance the rate of contraction as well as that of relaxation (by 23.2 +/- 3.7 and 27.8 +/- 7.7%, respectively), which culminated in an increased peak contractile force. However, at 10 mumol/l, the positive inotropic effect of TRH (i.e. the increase in peak contractile force) was smaller than at 1 mumol/l, which apparently was due to both a reduced TRH-induced elevation in the rate of contraction (12.4 +/- 3.2%) and a TRH-induced decrease in relaxation rate (11.1 +/- 8.1%). Since TRH is expressed in the heart, the above findings suggest that, in addition to its CNS-mediated cardiovascular effects, TRH modulates cardiac contractility as an autocrine regulator in a concentration-dependent manner, which likely involves more than one TRH receptor and associated signaling pathway. Thyrotropin-releasing hormone (TRH) and its mRNA have been identified in the rat heart, and TRH can enhance cardiomyocyte contractility in vivo. At present, little is known about cardiac TRH gene transcriptional regulation in the heart. Hormones and neurotransmitters, including thyroid hormone (T3), glucocorticoids, testosterone, and 5-HT initiate effects not only in the cardiovascular system, but also in the regulation of hypothalamic TRH. To clarify the potential roles of these modulators upon the cardiac TRH gene transcription, rat TRH promoter activity was assessed in rat embryonic myocyte cells (H9C2) by transient transfection assays. TRH promoter activity was stimulated significantly by dexamethasone (10(-4) M) and testosterone (10(-5) M), and was inhibited by T3 (10(-7) M). Interestingly, the neurotransmitter 5-HT stimulated TRH promoter activity in H9C2 cells, but not in HTB-11 cells. To further clarify this selective role of 5-HT on TRH promoter transcriptional activity in cardiac cells, 5-HT receptor antagonists and agonists were tested. A selective 5-HT2 receptor antagonist blocked 5-HT stimulation, whereas 5-HT agonist analogs caused augmentative effects when combined with 5-HT. Neither 5-HT nor any antagonists or agonists influenced H9C2 cell growth or morphology. These data suggest that 5-HT is an important transcriptional regulator of the cardiac TRH gene. BACKGROUND: We reported previously that left ventricular gene expression for thyrotropin-releasing hormone (TRH) precursor was increased in rats with heart failure 8 weeks after myocardial infarction (MI) and that early ACE inhibition tended to cause further myocardial induction of this gene. METHODS AND RESULTS: Here, we show that after MI, the expression of pro-TRH is induced in the heart coordinately with the protease PC1, an important enzyme in TRH biosynthesis. Pro-TRH gene expression was induced in cardiac interstitial cells after MI, and this effect was restricted to the heart, because no increase in TRH mRNA abundance was observed in the hypothalamus, kidney, or lung. Transcript abundance of pro-TRH can be increased in cultured cardiac fibroblasts by several adrenergic agonists, indicating that the adrenergic axis may play a regulatory role in cardiac TRH production. Acute intravenous administration of TRH to rats with ischemic cardiomyopathy caused a significant increase in heart rate, mean arterial pressure, cardiac output, stroke volume, and cardiac contractility. CONCLUSIONS: Taken together, these results indicate that TRH is specifically induced in the heart after MI and that it can increase cardiac performance in rats with ischemic cardiomyopathy. Thus, in addition to catecholamine and angiotensin II, pro-TRH/TRH may be another important axis that affects hemodynamics and cardiac function in heart failure.
Proteomic analyses need prior knowledge of the organism complete genome. Is the complete genome of the bacteria of the genus Arthrobacter available?
Yes, the complete genome sequence of Arthrobacter (two strains) is deposited in GenBank.
Arthrobacter phethrenivorans is the type species of the genus, and is able to metabolize phethrene as a sole source of carbon and energy. A. phethrenivorans is an aerobic, non-motile, and Gram-positive bacterium, exhibiting a rod-coccus growth cycle which was originally isolated from a creosote polluted site in Epirus, Greece. Here we describe the features of this organism, together with the complete genome sequence, and annotation. Arthrobacter sp. B6 is a Gram-positive, non-motile, facultative aerobic bacterium, isolated from the arsenic-contaminated aquifer sediment in the Datong basin, China. This strain displays high resistance to arsenic, and can dynamically transform arsenic under aerobic condition. Here, we described the high quality draft genome sequence, annotations and the features of Arthrobacter sp. B6. The G + C content of the genome is 64.67%. This strain has a genome size of 4,663,437 bp; the genome is arranged in 8 scaffolds that contain 25 contigs. From the sequences, 3956 protein-coding genes, 264 pseudo genes and 89 tRNA/rRNA-encoding genes were identified. The genome analysis of this strain helps to better understand the mechanism by which the microbe efficiently tolerates arsenic in the arsenic-contaminated environment. Author information: (1)State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, 150090, Harbin, China; Section of Sanitary Engineering, Department of Water Management, Delft University of Technology, 2628CN, Delft, The Netherlands. (2)State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, 150090, Harbin, China. (3)Section of Sanitary Engineering, Department of Water Management, Delft University of Technology, 2628CN, Delft, The Netherlands. (4)State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, 150090, Harbin, China. Electronic address: [email protected]. (5)State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, 150090, Harbin, China. Electronic address: [email protected]. Author information: (1)Department of Applied Chemistry, Graduate School of Engineering, University of Hyogo, Himeji, Hyogo, Japan. (2)Graduate School of Science and Engineering, Kagoshima University, Korimoto, Kagoshima, Japan. (3)Department of Applied Chemistry, Graduate School of Engineering, University of Hyogo, Himeji, Hyogo, Japan [email protected]. Author information: (1)Department of Biology, University of Florence, Florence, Italy. (2)Department of Experimental and Clinical Medicine, University of Florence, Florence, Italy. (3)Center for Integrative Medicine, Careggi University Hospital, University of Florence, Florence, Italy. (4)Department of Surgery and Translational Medicine, University of Florence, Florence, Italy. (5)Clinical Microbiology and Virology Unit, Careggi University Hospital, Florence, Italy. (6)Department of Biology, University of Florence, Florence, Italy [email protected]. Arthrobacter alpinus R3.8 is a psychrotolerant bacterial strain isolated from a soil sample obtained at Rothera Point, Adelaide Island, close to the Antarctic Peninsula. Strain R3.8 was sequenced in order to help discover potential cold active enzymes with biotechnological applications. Genome analysis identified various cold adaptation genes including some coding for anti-freeze proteins and cold-shock proteins, genes involved in bioremediation of xenobiotic compounds including naphthalene, and genes with chitinolytic and N-acetylglucosamine utilization properties and also plant-growth-influencing properties. In this genome report, we present a complete genome sequence of A. alpinus strain R3.8 and its annotation data, which will facilitate exploitation of potential novel cold-active enzymes.
What is the structural fold of bromodomain proteins?
The structure fold of the bromodomains is an all-alpha-helical fold, which includes a left-handed four-helix bundle topology, with two short additional helices in a long connecting loop.
Histone acetylation is important in chromatin remodelling and gene activation. Nearly all known histone-acetyltransferase (HAT)-associated transcriptional co-activators contain bromodomains, which are approximately 110-amino-acid modules found in many chromatin-associated proteins. Despite the wide occurrence of these bromodomains, their three-dimensional structure and binding partners remain unknown. Here we report the solution structure of the bromodomain of the HAT co-activator P/CAF (p300/CBP-associated factor). The structure reveals an unusual left-handed up-and-down four-helix bundle. In addition, we show by a combination of structural and site-directed mutagenesis studies that bromodomains can interact specifically with acetylated lysine, making them the first known protein modules to do so. The nature of the recognition of acetyl-lysine by the P/CAF bromodomain is similar to that of acetyl-CoA by histone acetyltransferase. Thus, the bromodomain is functionally linked to the HAT activity of co-activators in the regulation of gene transcription. TFIID is a large multiprotein complex that initiates assembly of the transcription machinery. It is unclear how TFIID recognizes promoters in vivo when templates are nucleosome-bound. Here, it is shown that TAFII250, the largest subunit of TFIID, contains two tandem bromodomain modules that bind selectively to multiply acetylated histone H4 peptides. The 2.1 angstrom crystal structure of the double bromodomain reveals two side-by-side, four-helix bundles with a highly polarized surface charge distribution. Each bundle contains an Nepsilon-acetyllysine binding pocket at its center, which results in a structure ideally suited for recognition of diacetylated histone H4 tails. Thus, TFIID may be targeted to specific chromatin-bound promoters and may play a role in chromatin recognition. The solution structure of the bromodomain from the human transcriptional coactivator GCN5 has been determined using NMR methods. The structure has a left-handed four-helix bundle topology, with two short additional helices in a long connecting loop. A hydrophobic groove and deep hydrophobic cavity are formed by loops at one end of the molecule. NMR binding experiments show that the cavity forms a specific binding pocket for the acetamide moiety. Peptides containing an N(epsilon)-acetylated lysine residue bind in this pocket with modest affinity (K(D) approximately 0.9 mM); no comparable binding occurs with unacetylated peptides. The GCN5 bromodomain binds the small ligands N(omega)-acetylhistamine and N-methylacetamide, confirming specificity for the alkyl acetamide moiety and showing that the primary element of recognition is simply the sterically unhindered terminal acetamide moiety of an acetylated lysine residue. Additional experiments show that binding is enhanced if the acetyl-lysine residue occurs within the context of a basic peptide and is inhibited by the presence of nearby acidic residues and by the carboxyl group of the free acetyl-lysine amino acid. The binding of the GCN5 bromodomain to acetylated peptides appears to have little additional sequence dependence, although weak interactions with other regions of the peptide are implicated by the binding data. Discrimination between ligands of positive and negative charge is attributed to the presence of several acidic residues located on the loops that form the sides of the binding pocket. Unlike the residues forming the acetamide binding cavity, these acidic side-chains are not conserved in other bromodomain sequences, suggesting that bromodomains might display differences in substrate selectivity and specificity as well as differences in function in vivo. BRD7 is an important protein tightly associated with Nasopharyngeal carcinoma (NPC). Overexpression of BRD7 inhibits NPC cell growth and cell cycle by transcriptionally regulating the cell cycle related genes. BRD7 contains a bromodomain that is found in many chromatin-associated proteins and in nearly all known nuclear histone acetyltransferases (HATs) and plays an important role in chromatin remodeling and transcriptional activation. Here, we report the solution structure of BRD7 bromodomain determined by NMR spectroscopy, and its binding specificity revealed by NMR titration with several acetylated histone peptides. We find that BRD7 bromodomain contains the typical left-handed four-helix bundle topology, and can bind with weak affinity to lysine-acetylated peptides derived from histone H3 with K9 or K14 acetylated and from histone H4 with K8, K12 or K16 acetylated. Our results show that BRD7 bromodomain lacks inherent binding specificity when binding to histones in vitro. Bromodomains represent an extensive family of evolutionarily conserved domains that are found in many chromatin-associated proteins such as histone acetyltransferases (HAT) and subunits of ATP-dependent chromatin-remodeling complexes. These domains are associated with acetylated lysine residues that bind both in vivo and in vitro; for example, they bind to the N-acetylated lysines of the histone tail of nucleosomes. In this report, we determined the structure of the bromodomain from human brahma-related gene 1 (BRG1) protein, a subunit of an ATP-dependent switching/sucrose nonfermenting (SWI/SNF) remodeling complex, and have also characterized its in vitro interaction with N-acetylated lysine peptides from histones. In addition to a typical all-alpha-helical fold that was observed in the bromodomains, we observed for the first time a small beta-sheet in the ZA loop region of the BRG1 protein. The BRG1 bromodomain exhibited binding, albeit weak, to acetylated peptides that were derived from histones H3 and H4. We have compared the acetyl-lysine binding sites of BRG1 bromodomain with the yGCN5 (general control of amino acid biosynthesis). By modeling the acetylated-lysine peptide into the BRG1 bromodomain structure, we were able to explain the weak binding of acetylated-lysine peptides to this bromodomain. BACKGROUND: Brd2 is a transcriptional regulator and belongs to BET family, a less characterized novel class of bromodomain-containing proteins. Brd2 contains two tandem bromodomains (BD1 and BD2, 46% sequence identity) in the N-terminus and a conserved motif named ET (extra C-terminal) domain at the C-terminus that is also present in some other bromodomain proteins. The two bromodomains have been shown to bind the acetylated histone H4 and to be responsible for mitotic retention on chromosomes, which is probably a distinctive feature of BET family proteins. Although the crystal structure of Brd2 BD1 is reported, no structure features have been characterized for Brd2 BD2 and its interaction with acetylated histones. RESULTS: Here we report the solution structure of human Brd2 BD2 determined by NMR. Although the overall fold resembles the bromodomains from other proteins, significant differences can be found in loop regions, especially in the ZA loop in which a two amino acids insertion is involved in an uncommon pi-helix, termed piD. The helix piD forms a portion of the acetyl-lysine binding site, which could be a structural characteristic of Brd2 BD2 and other BET bromodomains. Unlike Brd2 BD1, BD2 is monomeric in solution. With NMR perturbation studies, we have mapped the H4-AcK12 peptide binding interface on Brd2 BD2 and shown that the binding was with low affinity (2.9 mM) and in fast exchange. Using NMR and mutational analysis, we identified several residues important for the Brd2 BD2-H4-AcK12 peptide interaction and probed the potential mechanism for the specific recognition of acetylated histone codes by Brd2 BD2. CONCLUSION: Brd2 BD2 is monomeric in solution and dynamically interacts with H4-AcK12. The additional secondary elements in the long ZA loop may be a common characteristic of BET bromodomains. Surrounding the ligand-binding cavity, five aspartate residues form a negatively charged collar that serves as a secondary binding site for H4-AcK12. We suggest that Brd2 BD1 and BD2 may possess distinctive roles and cooperate to regulate Brd2 functions. The structure basis of Brd2 BD2 will help to further characterize the functions of Brd2 and its BET members.
List the endoscopic diagnoses that have been reported in children with autism
Endoscopic examinations in autistic children have been reported to show : I or II reflux esophagitis, Achalasia, chronic gastritis and chronic duodenitis, mild acute and chronic inflammation of the small bowel and colorectum and Ileo-colonic lymphoid nodular hyperplasia (LNH). The number of Paneth's cells in the duodenal crypts was found to be significantly elevated in autistic children compared with non-autistic control subjects. Low intestinal carbohydrate digestive enzyme activity was reported although there was no abnormality found in pancreatic function. Autistic children have ben reported to have an increased pancreatico-biliary fluid output after intravenous secretin administration.
We report three children with autistic spectrum disorders who underwent upper gastrointestinal endoscopy and intravenous administration of secretin to stimulate pancreaticobiliary secretion. All three had an increased pancreaticobiliary secretory response when compared with nonautistic patients (7.5 to 10 mL/min versus 1 to 2 mL/min). Within 5 weeks of the secretin infusion, a significant amelioration of the children's gastrointestinal symptoms was observed, as was a dramatic improvement in their behavior, manifested by improved eye contact, alertness, and expansion of expressive language. These clinical observations suggest an association between gastrointestinal and brain function in patients with autistic behavior. OBJECTIVES: Our aim was to evaluate the structure and function of the upper gastrointestinal tract in a group of patients with autism who had gastrointestinal symptoms. STUDY DESIGN: Thirty-six children (age: 5.7 +/- 2 years, mean +/- SD) with autistic disorder underwent upper gastrointestinal endoscopy with biopsies, intestinal and pancreatic enzyme analyses, and bacterial and fungal cultures. The most frequent gastrointestinal complaints were chronic diarrhea, gaseousness, and abdominal discomfort and distension. RESULTS: Histologic examination in these 36 children revealed grade I or II reflux esophagitis in 25 (69.4%), chronic gastritis in 15, and chronic duodenitis in 24. The number of Paneth's cells in the duodenal crypts was significantly elevated in autistic children compared with non-autistic control subjects. Low intestinal carbohydrate digestive enzyme activity was reported in 21 children (58.3%), although there was no abnormality found in pancreatic function. Seventy-five percent of the autistic children (27/36) had an increased pancreatico-biliary fluid output after intravenous secretin administration. Nineteen of the 21 patients with diarrhea had significantly higher fluid output than those without diarrhea. CONCLUSIONS: Unrecognized gastrointestinal disorders, especially reflux esophagitis and disaccharide malabsorption, may contribute to the behavioral problems of the non-verbal autistic patients. The observed increase in pancreatico-biliary secretion after secretin infusion suggests an upregulation of secretin receptors in the pancreas and liver. Further studies are required to determine the possible association between the brain and gastrointestinal dysfunctions in children with autistic disorder. OBJECTIVES: A relationship between autism and gastrointestinal (GI) immune dysregulation has been postulated based on incidence of GI complaints as well as macroscopically observed lymphonodular hyperplasia and microscopically determined enterocolitis in pediatric patients with autism. To evaluate GI immunity, we quantitatively assessed levels of proinflammatory cytokines, interleukin (IL)-6, IL-8, and IL-1beta, produced by intestinal biopsies of children with pervasive developmental disorders. METHODS: Fifteen patients, six with pervasive developmental disorders and nine age-matched controls, presenting for diagnostic colonoscopy were enrolled. Endoscopic biopsies were organ cultured, supernatants were harvested, and IL-6, IL-8, and IL-1beta levels were quantified by ELISA. Tissue histology was evaluated by blinded pathologists. RESULTS: Concentrations of IL-6 from intestinal organ culture supernatants of patients with pervasive developmental disorders (median 318.5 pg/ml, interquartile range 282.0-393.0 pg/ml) when compared with controls (median 436.9 pg/ml, interquartile range 312.6-602.5 pg/ml) were not significantly different (p = 0.0987). Concentrations of IL-8 (median 84,000 pg/ml, interquartile range 16,000-143,000 pg/ml) when compared with controls (median 177,000 pg/ml, interquartile range 114,000-244,000 pg/ml) were not significantly different (p = 0.0707). Concentrations of IL-1beta (median 0.0 pg/ml, interquartile range 0.0-94.7 pg/ml) when compared with controls (median 0.0 pg/ml, interquartile range 0.0-60.2 pg/ml) were not significantly different (p = 0.8826). Tissue histology was nonpathological for all patients. CONCLUSIONS: We have demonstrated no significant difference in production of IL-6, IL-8, and IL-1beta between patients with pervasive developmental disorders and age-matched controls. In general, intestinal levels of IL-6 and IL-8 were lower in patients with pervasive developmental disorders than in age-matched controls. These data fail to support an association between autism and GI inflammation. BACKGROUND: Intestinal mucosal pathology, characterized by ileo-colonic lymphoid nodular hyperplasia (LNH) and mild acute and chronic inflammation of the colorectum, small bowel and stomach, has been reported in children with autistic spectrum disorder (ASD). AIM: To assess ileo-colonic LNH in ASD and control children and to test the hypothesis that there is an association between ileo-colonic LNH and ASD in children. PATIENTS AND METHODS: One hundred and forty-eight consecutive children with ASD (median age 6 years; range 2-16; 127 male) with gastrointestinal symptoms were investigated by ileo-colonoscopy. Macroscopic and histological features were scored and compared with 30 developmentally normal (non-inflammatory bowel disease, non-coeliac disease) controls (median age 7 years; range 1-11; 25 male) showing mild non-specific colitis in 16 cases (13 male) and normal colonic histology in 14 cases (12 male). Seventy-four ASD children and 23 controls also underwent upper gastrointestinal endoscopy. The influence on ileal LNH of dietary restriction, age at colonoscopy, and co-existent LNH elsewhere in the intestine, was examined. RESULTS: The prevalence of LNH was significantly greater in ASD children compared with controls in the ileum (129/144 (90%) vs. 8/27 (30%), P < 0.0001) and colon (88/148 (59%) vs. 7/30 (23%), P = 0.0003), whether or not controls had co-existent colonic inflammation. The severity of ileal LNH was significantly greater in ASD children compared with controls, with moderate to severe ileal LNH present in 98 of 144 (68%) ASD children versus 4 of 27 (15%) controls (P < 0.0001). Severe ileal LNH was associated with co-existent colonic LNH in ASD children (P = 0.01). The presence and severity of ileal LNH was not influenced by either diet or age at colonoscopy (P = 0.2). Isolated ileal LNH without evidence of pathology elsewhere in the intestine was a rare event, occurring in less than 3% of children overall. On histopathological examination, hyperplastic lymphoid follicles are significantly more prevalent in the ileum of ASD children (84/138; 61%) compared with controls (2/23; 9%, P = 0.0001). CONCLUSION: Ileo-colonic LNH is a characteristic pathological finding in children with ASD and gastrointestinal symptoms, and is associated with mucosal inflammation. Differences in age at colonoscopy and diet do not account for these changes. The data support the hypothesis that LNH is a significant pathological finding in ASD children. Chronic gastrointestinal symptoms are commonly reported in autistic patients. Dysphagia is often present, and it is generally related to behavioral eating disorders. The association between autism and esophageal achalasia has not been described in literature yet. We report our experience with three cases of autistic children we recently treated for esophageal achalasia. In the first case (a 14-year-old male), achalasia was diagnosed with barium swallow and esophageal manometry and was successfully treated with three pneumatic endoscopic dilatations (follow-up: 3 years). In the second case (a 12-year-old female), achalasia was diagnosed with barium swallow and esophageal manometry and was treated with Heller myotomy after two unsuccessful pneumatic endoscopic attempts (follow-up: 3 months). In the last case, a 15-year-old male underwent barium swallow and endoscopy that confirmed achalasia. He was treated with Heller myotomy, and he is asymptomatic at a 6-month follow-up. To our knowledge, this is the first report of a possible association between autism and esophageal achalasia. Because of the rarity of both diseases, their association in the same patient is unlikely to be casual even if speculation on their common etiology is impossible at present. This finding needs further confirmation, but it is sufficient, in our opinion, to indicate proper evaluation with barium swallow and/or manometry in any autistic children with eating difficulty.
What are the outcomes of Renal sympathetic denervation?
Significant decreases and progressively higher reductions of systolic and diastolic blood pressure were observed after RSD. The complication rate was minimal. Renal sympathetic denervation also reduces heart rate, which is a surrogate marker of cardiovascular risk.
Despite the considerable advances in the treatment of hypertension that have been made over the past few decades, adequate management and control of this condition remains poor, and efforts are ongoing to develop new strategies to improve related outcomes. Novel therapeutic approaches to the management of systemic hypertension fall into two major categories: (i) those that seek to improve blood pressure-lowering efficacy using new therapeutic strategies in addition to standard non-pharmacological and pharmacological approaches and (ii) novel ways to optimize and improve the efficacy and utility of existing therapies. Novel procedure- and device-based strategies to control hypertension include renal sympathetic denervation and baroreflex sensitization. These two techniques will be the focus of the present review. Hypertension represents a significant global public health concern, contributing to vascular and renal morbidity, cardiovascular mortality, and economic burden. The opportunity to influence clinical outcomes through hypertension management is therefore paramount. Despite adherence to multiple available medical therapies, a significant proportion of patients have persistent blood pressure elevation, a condition termed resistant hypertension. Recent recognition of the importance of the renal sympathetic and somatic nerves in modulating blood pressure and the development of a novel procedure that selectively removes these contributors to resistant hypertension represents an opportunity to provide clinically meaningful benefit across wide and varied patient populations. Early clinical evaluation with catheter-based, selective renal sympathetic denervation in patients with resistant hypertension has mechanistically correlated sympathetic efferent denervation with decreased renal norepinephrine spillover and renin activity, increased renal plasma flow, and has demonstrated clinically significant, sustained reductions in blood pressure. The SYMPLICITY HTN-3 Trial is a pivotal study designed as a prospective, randomized, masked procedure, single-blind trial evaluating the safety and effectiveness of catheter-based bilateral renal denervation for the treatment of uncontrolled hypertension despite compliance with at least 3 antihypertensive medications of different classes (at least one of which is a diuretic) at maximal tolerable doses. The primary effectiveness endpoint is measured as the change in office-based systolic blood pressure from baseline to 6 months. This manuscript describes the design and methodology of a regulatory trial of selective renal denervation for the treatment of hypertension among patients who have failed pharmacologic therapy. Systemic hypertension represents a significant global concern, because it contributes to vascular and renal morbidity, cardiovascular mortality, and economic burden, hence the impact of hypertension is a major issue in public health worldwide. Improving high blood pressure management is therefore fundamental to influencing clinical outcomes. Despite adherence to multiple available medical therapies, a significant proportion of patients has persistent blood pressure elevation, a condition termed "resistant hypertension". Renal sympathetic innervations contribute to lack of response of anti-hypertensive drugs through an imbalance of regulatory mechanisms. Renal afferent nerve fibers are responsible for sympathetic activation and contribute to blood pressure homeostasis while afferent signals from the kidneys are integrated at the central nervous system and enhance sympathetic nerve discharge. In this regard, a novel strategy that selectively removes these hypertensive contributors represents a new therapeutic opportunity. Recently, a catheter-based method to induce renal sympathetic denervation has been introduced into daily practice. Clinical evaluation of selective renal sympathetic denervation demonstrated a decrease of renal norepinephrine spillover and renin activity, an increase of renal plasma flow, and has confirmed clinically significant, sustained reductions in blood pressure in patients with resistant hypertension. This review summarizes the available data on the role of sympathetic activation in the pathophysiology of hypertension and the current concepts in transcatheter renal artery ablation with radiofrequency delivery for systemic hypertension. Suggestions regarding targets for future systemic hypertension management are also described. Resistant hypertension is an increasingly prevalent health problem associated with important adverse cardiovascular outcomes. The pathophysiology that underlies this condition involves increased function of both the sympathetic nervous system and the renin-angiotensin II-aldosterone system. A crucial link between these 2 systems is the web of sympathetic fibres that course within the adventitia of the renal arteries. These nerves can be targeted by applying radiofrequency energy from the lumen of the renal arteries to renal artery walls (percutaneous renal sympathetic denervation [RSD]), an approach that has attracted great interest. This paper critically reviews the evidence supporting the use of RSD. Small studies suggest that RSD can produce dramatic blood pressure reductions: In the randomized Symplicity HTN-2 trial of 106 patients, the mean fall in blood pressure at 6 months in patients who received the treatment was 32/12 mm Hg. However, there are limitations to the evidence for RSD in the treatment of resistant hypertension. These include the small number of patients studied; the lack of any placebo-controlled evidence; the fact that blood pressure outcomes were based on office assessments, as opposed to 24-hour ambulatory monitoring; the lack of longer-term efficacy data; and the lack of long-term safety data. Some of these concerns are being addressed in the ongoing Renal Denervation in Patients With Uncontrolled Hypertension (Symplicity HTN-3) trial. The first percutaneous RSD system was approved by Health Canada in the spring of 2012. But until more and better-quality data are available, this procedure should generally be reserved for those patients whose resistant hypertension is truly uncontrolled. Renal afferent and efferent sympathetic nerves are involved in the regulation of blood pressure and have a pathophysiological role in hypertension. Renal sympathetic denervation is a novel therapeutic technique for the treatment of patients with resistant hypertension. Clinical trials of renal sympathetic denervation have shown significant reductions in blood pressure in these patients. Renal sympathetic denervation also reduces heart rate, which is a surrogate marker of cardiovascular risk. Conditions that are comorbid with hypertension, such as heart failure and myocardial hypertrophy, obstructive sleep apnoea, atrial fibrillation, renal dysfunction, and metabolic syndrome are closely associated with enhanced sympathetic activity. In experimental models and case-control studies, renal denervation has had beneficial effects on these conditions. Renal denervation could become a commonly used procedure to treat resistant hypertension and chronic diseases associated with enhanced sympathetic activation. Current work is focused on refining the techniques and interventional devices to provide safe and effective renal sympathetic denervation. Controlled studies in patients with mild-to-moderate, nonresistant hypertension and comorbid conditions such as heart failure, diabetes mellitus, sleep apnoea, and arrhythmias are needed to investigate the capability of renal sympathetic denervation to improve cardiovascular outcomes. 1. The authors review the concept of resistant hypertension and the involvement of the sympathetic nervous system in hypertension as a rational basis for the technique of renal sympathetic denervation (RSD) performed percutaneously. This revision is the result of an active search for scientific articles with the term "renal denervation" in the Medline and PubMed databases. The techniques and devices used in the procedure are presented, as well as clinical outcomes at six, 12 and 24 months after the intervention with the Symplicity catheter. Significant decreases and progressively higher reductions of systolic and diastolic blood pressure were observed after RSD. The complication rate was minimal. New devices for RSD and its ongoing clinical studies are cited. In conclusion, the RSD presents itself as an effective and safe approach to resistant hypertension. Results from ongoing studies and longer follow-up of these patients are expected to confirm the initial results and put into perspective the expansion of the procedure use in hypertension approach.
Which MAP kinase phosphorylates the transcription factor c-jun?
c-Jun is phosphorylated by c-Jun NH2-terminal kinase (JNK).
Tyrosine kinase growth factor receptors activate MAP kinase by a complex mechanism involving the SH2/3 protein Grb2, the exchange protein Sos, and Ras. The GTP-bound Ras protein binds to the Raf kinase and initiates a protein kinase cascade that leads to MAP kinase activation. Three MAP kinase kinase kinases have been described--c-Raf, c-Mos, and Mekk--that phosphorylate and activate Mek, the MAP kinase kinase. Activated Mek phosphorylates and activates MAP kinase. Subsequently, the activated MAP kinase translocates into the nucleus where many of the physiological targets of the MAP kinase signal transduction pathway are located. These substrates include transcription factors that are regulated by MAP kinase phosphorylation (e.g., Elk-1, c-Myc, c-Jun, c-Fos, and C/EBP beta). Thus the MAP kinase pathway represents a significant mechanism of signal transduction by growth factor receptors from the cell surface to the nucleus that results in the regulation of gene expression. Three MAP kinase homologs have been identified in the rat: Erk1, Erk2, and Erk3. Human MAP kinases that are similar to the rat Erk kinases have also been identified by molecular cloning. The human Erk1 protein kinase has been shown to be widely expressed as a 44-kDa protein in many tissues. The human Erk2 protein kinase is a 41-kDa protein that is expressed ubiquitously. In contrast, a human Erk3-related protein kinase has been found to be expressed at a high level only in heart muscle and brain. The loci of these MAP kinase genes are widely distributed within the human genome: erk2 at 22q11.2; erk1 at 16p11.2; and ek3-related at 18q12-21. In the yeast Saccharomyces cerevisiae, five MAP kinase gene homologs have been described: smkl, mpk1, hog1, fus3, and kss1. Together, these kinases are a more diverse group than the human erks that have been identified. Thus the erks are likely to represent only one subgroup of a larger human MAP kinase gene family. A candidate for this extended family of MAP kinases is the c-Jun NH2-terminal kinase (Jnk), which binds to and phosphorylates the transcription factor c-Jun at the activating sites Ser-63 and Ser-73. Evidence is presented here to demonstrate that Jnk is a distant relative of the MAP kinase group that is activated by dual phosphorylation at Tyr and Thr. In the CNS, astrocytes are significant sources of RANTES/CCL5 (regulated upon activation, normal T cell expressed and secreted), a CC-chemokine with important biological function. Astrocyte RANTES/CCL5 has been shown to be induced by interleukin-1 (IL-1), with interferon-gamma (IFNgamma) as a primer, but whether type I interferons play any role in the expression of RANTES/CCL5 is not known. In this report, we studied the detailed mechanism of RANTES/CCL5 induction in primary human astrocytes activated with IL-1 and IFNbeta. Ribonuclease protection assay and ELISA showed that IFNbeta, although not effective alone, increased IL-1-induced RANTES/CCL5 expression, but did not antagonize IFNgamma. IL-1 or IL-1/IFNbeta-induced RANTES/CCL5 expression was inhibited by the super-repressor IkappaBalpha or inhibitors of p38 or c-Jun N-terminal kinase (JNK) MAPKs (mitogen-activated protein kinases), but not by extracellular signal regulated kinases (ERK) inhibitors. IFNbeta enhanced IL-1-induced phosphorylation of p38 MAPK, but was not effective alone. Transfection with mutated RANTES/CCL5 promoter-reporter constructs revealed that kappaB, interferon-stimulated response element (ISRE) and CAATT-enhancer binding protein-beta (C/EBPbeta) sites all contributed to IL-1/IFNbeta-induced RANTES/CCL5 transcription. IFNbeta synergized with IL-1 to induce nuclear accumulation of C/EBPbeta protein. They also synergized to form nuclear ISRE complexes with Stat1, Stat2 and interferon regulatory factor-1 (IRF-1) proteins. Together, our results demonstrate that IFNbeta plays a positive regulatory role in the expression of RANTES/CCL5 in human astrocytes through several distinct mechanisms. c-Jun N-terminal kinases (JNKs) are a group of mitogen-activated protein kinase family members that are important in regulating cell growth, proliferation, and apoptosis. Activation of the JNK pathway has been implicated in the formation of several human tumors. We have previously demonstrated that a 55-kDa JNK isoform is constitutively activated in 86% of human brain tumors and more recently demonstrated that this isoform is either JNK2alpha2 or JNK2beta2. Importantly, we have also found that among the 10 known JNK isoforms, the JNK2 isoforms are unique in their ability to autophosphorylate in vitro and in vivo. This does not require the participation of any upstream kinases and also leads to substrate kinase activity in vitro and in vivo. To clarify the mechanism of JNK2alpha2 autoactivation, we have generated a series of chimeric cDNAs joining portions of JNK1alpha2, which does not have detectable autophosphorylation activity, with portions of JNK2alpha2, which has the strongest autophosphorylation activity. Through in vivo and in vitro kinase assays, we were able to define a domain ranging from amino acids 218 to 226 within JNK2alpha2 that is required for its autophosphorylation. Mutation of JNK2alpha2 to its counterpart of JNK1alpha2 in this region abrogated the autophosphorylation activity and c-Jun substrate kinase activity in vivo and in vitro. Notably, switching of JNK1alpha2 to JNK2alpha2 at this 9-amino acid site enabled JNK1alpha2 to gain the autophosphorylation activity in vivo and in vitro. We also found two other functional sites that participate in JNK2alpha2 activity. One site ranging from amino acids 363 to 382 of JNK2alpha2 is required for efficient c-Jun binding in vitro, and a site ranging from amino acids 383 to 424 enhances autophosphorylation intensity, although it is not required for triggering the autophosphorylation in vitro. These findings have uncovered the regions required for JNK2alpha2 autophosphorylation, and this information could be used as potential targets to block JNK2alpha2 activation. The c-Jun N-terminal kinases (JNKs) are members of the mitogen-activated protein kinase (MAPK) family and are activated by environmental stress. JNK is also activated by proinflammatory cytokines, such as TNF and IL-1, and Toll-like receptor ligands. This pathway, therefore, can act as a critical convergence point in immune system signaling for both adaptive and innate responses. Like other MAPKs, the JNKs are activated via the sequential activation of protein kinases that includes two dual-specificity MAP kinase kinases (MKK4 and MKK7) and multiple MAP kinase kinase kinases. MAPKs, including JNKs, can be deactivated by a specialized group of phosphatases, called MAP kinase phosphatases. JNK phosphorylates and regulates the activity of transcription factors other than c-Jun, including ATF2, Elk-1, p53 and c-Myc and non-transcription factors, such as members of the Bcl-2 family. The pathway plays a critical role in cell proliferation, apoptosis, angiogenesis and migration. In this review, an overview of the functions that are related to rheumatic diseases is presented. In addition, some diseases in which JNK participates will be highlighted. The c-Jun N-terminal kinase (JNK) pathway forms part of the mitogen-activated protein kinase (MAPK) signaling pathways comprising a sequential three-tiered kinase cascade. Here, an upstream MAP3K (MEKK1) phosphorylates and activates a MAP2K (MKK4 and MKK7), which in turn phosphorylates and activates the MAPK, JNK. The C-terminal kinase domain of MEKK1 (MEKK-C) is constitutively active, while MKK4/7 and JNK are both activated by dual phosphorylation of S/Y, and T/Y residues within their activation loops, respectively. While improvements in the purification of large quantities of active JNKs have recently been made, inadequacies in their yield, purity, and the efficiency of their phosphorylation still exist. We describe a novel and robust method that further improves upon the purification of large yields of highly pure, phosphorylated JNK1β1, which is most suitable for biochemical and biophysical characterization. Codon harmonization of the JNK1β1 gene was used as a precautionary measure toward increasing the soluble overexpression of the kinase. While JNK1β1 and its substrate ATF2 were both purified to >99% purity as GST fusion proteins using GSH-agarose affinity chromatography and each cleaved from GST using thrombin, constitutively-active MEKK-C and inactive MKK4 were separately expressed in E. coli as thioredoxin-His(6)-tagged proteins and purified using urea refolding and Ni(2+)-IMAC, respectively. Activation of JNK1β1 was then achieved by successfully reconstituting the JNK MAPK activation cascade in vitro; MEKK-C was used to activate MKK4, which in turn was used to efficiently phosphorylate and activate large quantities of JNK1β1. Activated JNK1β1 was thereafter able to phosphorylate ATF2 with high catalytic efficiency. Tylophorine, a phethroindolizidine alkaloid, is the major medicinal constituent of herb Tylophora indica. Tylophorine treatment increased the accumulation of c-Jun protein, a component of activator protein 1 (AP1), in carcinoma cells. An in vitro kinase assay revealed that the resultant c-Jun phosphorylation was primarily mediated via activated c-Jun N-terminal protein kinase (JNK). Moreover, flow cytometry indicated that ectopically overexpressed c-Jun in conjunction with tylophorine significantly increased the number of carcinoma cells that were arrested at the G1 phase. The tylophorine-mediated downregulation of cyclin A2 protein levels is known to be involved in the primary G1 arrest. Chromatin immunoprecipitation and reporter assays revealed that tylophorine enhanced the c-Jun downregulation of the cyclin A2 promoter activity upon increased binding of c-Jun to the deregulation AP1 site and decreased binding to the upregulation activating transcription factor (ATF) site in the cyclin A2 promoter, thereby reducing cyclin A2 expression. Further, biochemical studies using pharmacological inhibitors and RNA silencing approaches demonstrated that tylophorine-mediated elevation of the c-Jun protein level occurs primarily via two discrete prolonged signaling pathways: (i) the NF-κB/PKCδ_(MKK4)_JNK cascade, which phosphorylates c-Jun and increases its stability by slowing its ubiquitination, and (ii) the PI3K_PDK1_PP2A_eEF2 cascade, which sustains eukaryotic elongation factor 2 (eEF2) activity and thus c-Jun protein translation. To the best of our knowledge, this report is the first to demonstrate the involvement of c-Jun in the anticancer activity of tylophorine and the release of c-Jun translation from a global translational blockade via the PI3K_PDK1_eEF2 signaling cascade. Cellular inflammatory response plays an important role in ischemic brain injury and anti-inflammatory treatments in stroke are beneficial. Dietary supplementation with docosahexaenoic acid (DHA) shows anti-inflammatory and neuroprotective effects against ischemic stroke. However, its effectiveness and its precise modes of neuroprotective action remain incompletely understood. This study provides evidence of an alternative target for DHA and sheds light on the mechanism of its physiological benefits. We report a global inhibitory effect of 3 consecutive days of DHA preadministration on circulating and intracerebral cellular inflammatory responses in a rat model of permanent cerebral ischemia. DHA exhibited a neuroprotective effect against ischemic deficits by reduction of behavioral disturbance, brain infarction, edema and blood-brain barrier disruption. The results of enzymatic assay, Western blot, real-time reverse transcriptase polymerase chain reaction and flow cytometric analysis revealed that DHA reduced central macrophages/microglia activation, leukocyte infiltration and pro-inflammatory cytokine expression and peripheral leukocyte activation after cerebral ischemia. In parallel with these immunosuppressive phenomena, DHA attenuated post-stroke oxidative stress, c-Jun N-terminal kinase (JNK) phosphorylation, c-Jun phosphorylation and activating protein-1 (AP-1) activation but further elevated ischemia-induced NF-E2-related factor-2 (Nrf2) and heme oxygenase-1 (HO-1) expression. DHA treatment also had an immunosuppressive effect in lipopolysaccharide/interferon-γ-stimulated glial cultures by attenuating JNK phosphorylation, c-Jun phosphorylation and AP-1 activation and augmenting Nrf2 and HO-1 expression. In summary, we have shown that DHA exhibited neuroprotective and anti-inflammatory effects against ischemic brain injury and these effects were accompanied by decreased oxidative stress and JNK/AP-1 signaling as well as enhanced Nrf2/HO-1 expression. Many clinical cases have been reported where epilepsy profoundly influenced the pathophysiological function of the heart; however, the underlying mechanisms were not elucidated. We use the tremor (TRM) rat as an animal model of epilepsy to investigate the potential mechanisms of myocardial injury. Cardiac functions were assessed by arrhythmia score, heart rate, heart:body mass ratio, and hemodynamic parameters including left ventricular systolic pressure (LVSP), left ventricular end-diastolic pressure (LVEDP), and maximum rate of left ventricular pressure rise and fall (+dp/dtmax and -dp/dtmax). Catecholamine level was detected by HPLC. Apoptotic index was estimated by TUNEL assay. The expressions of Bcl-2, Bax, caspase-3, extracellular signal-regulated protein kinase (ERK), c-Jun NH2-terminal protein kinases (JNK), and p38 were evaluated by Western blot. The results indicated that there existed cardiac dysfunction and cardiomyocyte apoptosis, accompanied by increasing catecholamine levels in TRM rats. Further investigation revealed that apoptosis was mediated by reducing Bcl-2, upregulating Bax, and activating caspase-3. Additional experiments demonstrated that P-ERK1/2 was decreased, whereas P-JNK and P-p38 were up-regulated. Our results suggest that the sympathetic nervous system activation and cardiomyocyte apoptosis are involved in the myocardial injury of TRM rats. The mechanisms of apoptosis might be associated with the activation of the mitochondria-initiated and the mitogen-activated protein kinase pathways. BACKGROUND: The c-Jun N-terminal kinase (JNK) is thought to be involved in inflammation, proliferation and apoptosis. AIM: To examine the role of JNK isoforms in metastasis, proliferation, migration and invasion of the maligt melanoma (MM) cell lines SK-MEL-28, SK-MEL-3 and WM164, using a kinase-specific inhibitor or isoform-specific small interfering (si)RNAs. RESULTS: SK-MEL-3, a cell line established from metastatic MM, showed slightly increased phosphorylation of both JNK1 and JNK2, whereas WM164, a cell line derived from primary MM, showed significant phosphorylation of JNK1. A JNK inhibitor, SP600125, inhibited cell proliferation of SK-MEL-3 but not SK-MEL-28 or WM164. Transfection of JNK1-specific siRNA reduced the migratory activity of WM164 cells, while silencing of either JNK1 or JNK2 strongly suppressed the invasive activity of SK-MEL-3. CONCLUSIONS: Our study suggests that JNK isoforms have different roles in MM. Metastasis of MM may be regulated by JNK2, while invasion is regulated by both JNK1 and JNK2. JNK1 and JNK2 respectively mediate cell migration and cell proliferation. Further understanding of the specific roles of JNK isoforms in the pathogenesis of MM may lead to the development of therapies targeting specific isoforms. Alzheimer's disease (AD) is characterized by accumulation of two misfolded and aggregated proteins, β-amyloid and hyperphosphorylated tau. Both cellular systems responsible for clearance of misfolded and aggregated proteins, the lysosomal and the proteasomal, have been shown to be malfunctioning in the aged brain and more so in patients with neurodegenerative diseases, including AD. This malfunction could be contributing to β-amyloid and tau accumulation, eventually aggregating in plaques and tangles. We have investigated the impact of decreased proteasome activity on tau phosphorylation as well as on microtubule stability and transport. To do this, we used our recently developed neuronal model where human SH-SY5Y cells obtain neuronal morphology and function through differentiation. We found that exposure to low doses of the proteasome inhibitor MG-115 caused tau phosphorylation, microtubule destabilization and disturbed neuritic transport. Furthermore, reduced proteasome activity activated several proteins implicated in tau phosphorylation and AD pathology, including c-Jun N-terminal kinase, c-Jun and extracellular signal-regulated protein kinase (ERK) 1/2. Restoration of the microtubule transport was achieved by inhibiting ERK 1/2 activation, and simultaneous inhibition of both ERK 1/2 and c-Jun reversed the proteasome inhibition-induced tau phosphorylation. Taken together, this study suggests that a decrease in proteasome activity can, through activation of c-Jun and ERK 1/2, result in several events related to neurodegenerative diseases. Restoration of proteasome activity or modulation of ERK 1/2 and c-Jun function can open new treatment possibilities against neurodegenerative diseases such as AD. Bone degradation is a serious complication of chronic inflammatory diseases such as septic arthritis, osteomyelitis, and infected orthopedic implant failure. Up to date, effective therapeutic treatments for bacteria-caused bone destruction are limited. In our previous study, we found that LPS promoted osteoclast differentiation and activity through activation of mitogen-activated protein kinases (MAPKs) pathway such as c-Jun N-terminal kinases (JNK) and extracellular signal regulated kinase (ERK1/2). The current study was to evaluate the mechanism of LPS on the apoptosis and osteoblast differentiation in MC3T3-E1 cells. MC3T3-E1 osteoblasts were non-treated, treated with LPS. After treatment, the cell viability, the activity of alkaline phosphatase (ALP) and caspase-3 were measured. The expressions of osteoblast-specific genes and Bax, Bcl-2, and caspase-3 were determined by real-time quantitative polymerase chain reaction (qPCR). Protein levels of Bax, Bcl-2, caspase-3, and phosphorylation of MAPKs were measured using Western blotting assays. The MAPK signaling pathway was blocked by pretreatment with JNK inhibitor SP600125. LPS treatment induced a significant decrease in cell metabolism, viability, and ALP activity in MC3T3-E1 cells. LPS also significantly decreased mRNA expressions of osteoblast-related genes in MC3T3-E1 cells. On the other hand, LPS significantly upregulated mRNA expressions and protein levels of Bax and caspase-3 as well as activation of caspase-3, whereas decreased Bcl-2 expression in MC3T3-E1 cells. Furthermore, LPS significantly promoted MAPK pathway including the phosphorylation of JNK and the phosphorylation of ERK1/2; moreover, pretreatment with JNK inhibitor not only attenuated both of phosphorylation-JNK and ERK1/2 enhanced by LPS in MC3T3-E1 cells, but also reversed the downregulated expressions of osteoblast-specific genes including ALP and BSP induced by LPS. In conclusion, LPS could induce osteoblast apoptosis and inhibit osteoblast differentiation via activation of JNK pathway. Sinodielide A (SA) is a naturally occurring guaianolide, which is isolated from the root of Sinodielsia yunensis. This root, commonly found in Yun province, is used in traditional Chinese medicine as an antipyretic, analgesic and diaphoretic agent. A number of studies have reported that agents isolated from a species of Umbelliferae (Apiaceae) have antitumor activities. We previously reported, using combined treatments with this medicinal herb and hyperthermia at various temperatures, an enhanced cytotoxicity in the human prostate cancer androgen‑independent cell lines, PC3 and DU145, and analyzed the related mechanisms. In the present study, we investigated the effects of treatment with SA prior to hyperthermia on the thermosensitivity of DU145 cells, and the mechanisms related to the induction of apoptosis and G(2)/M cell cycle arrest via the activation of extracellular-regulated kinase (ERK)1/2, c-Jun N-terminal kinase (JNK) mitogen-activated protein kinase (MAPK) signaling pathways, as well as the phosphoinositide 3-kinase (PI3K)/Akt signaling pathways. Cells were exposed to hyperthermia alone (40-44˚C) or hyperthermia in combination with SA. Lethal damage to cells treated with mild hyperthermia (40 or 42˚C) for up to 6 h was slight; however, hyperthermia in combination with SA synergistically enhanced thermosensivity. Lethal damage to cells treated with acute hyperthermia (43 or 44˚C) was more severe, but these effects were also enhanced and were more significant by the combined treatment with SA. The kinetics of apoptosis induction and cell cycle distribution were analyzed by flow cytometry. In addition, the levels of ERK1/2, JNK and Akt were determined by western blot analysis. The incidence of apoptotic cells after treatment with SA (20.0 µM) at 37˚C for 4 h, hyperthermia (44˚C) alone for 30 min, and the combination in sequence were examined. The sub-G1 division (%) in the diagram obtained by flow cytometry was applied to that assay. The percentage of apoptotic cells (10.53±5.02%) was higher at 48 h as compared to 0, 12 and 24 h after treatment. The distribution of DU145 cells in the G2/M cell cycle phase was markedly increased after 24 h of heating at 44˚C and after the combined treatment with heating and SA. The phosphorylation of ERK1/2 was reduced following treatment with heating and SA, while the levels of phosphorylated JNK (p-JNK) were markedly increased immediately after heating at 44˚C and when heating was combined with SA. By contrast, the levels of phosphorylated Akt (p-Akt) were immediately increased only after heating at 44˚C. Thus, we concluded that SA exerts its thermosensitizing effects on DU145 cells by inhibiting the activation of the MAPK/ERK1/2 and PI3K/Akt signaling pathways. We previously reported that jellyfish collagen stimulates both the acquired and innate immune responses. In the acquired immune response, jellyfish collagen enhanced immunoglobulin production by lymphocytes in vitro and in vivo. Meanwhile, in the innate immune response jellyfish collagen promoted cytokine production and phagocytotic activity of macrophages. The facts that jellyfish collagen plays several potential roles in stimulating cytokine production by macrophages have further attracted us to uncover its mechanisms. We herein describe that the cytokine production-stimulating activity of jellyfish collagen was canceled by a Toll-like receptor 4 (TLR4) inhibitor. Moreover, jellyfish collagen stimulated phosphorylation of inhibitor of κBα (IκBα), promoted the translocation of nucleus factor-κB (NF-κB), and activated c-Jun N-terminal kinase (JNK). A JNK inhibitor also abrogated the cytokine production-stimulating activity of jellyfish collagen. These results suggest that jellyfish collagen may facilitate cytokine production by macrophages through activation of NF-κB and JNK via the TLR4 signaling pathways. Previous reports suggested that protoapigenone showed remarkable antitumor activities against a broad spectrum of human cancer cell lines, but had no effect on human lung adenocarcinoma A549 cell. The lack of effective remedies had necessitated the application of new therapeutic scheme. A novel compound RY10-4 which has the similar structure close to protoapigenone showed better antitumor activity. Treatment with RY10-4 inhibited the expression of pro-caspase-3, pro-caspase-9, Bcl-2 as well as phosphorylation of signal transducer and activator of transcription-3 (p-STAT3). It also reduced the expressions of matrix metalloproteinase-2 (MMP-2), matrix metalloproteinase-9 (MMP-9) and increases the expressions of reversion-inducing cysteine-rich protein with kazal motifs (RECK), as well as tissue inhibitor of metalloproteinase (TIMP) via inhibiting STAT3 by activating the mitogen-activated protein (MAP) kinases (the c-Jun N-terminal kinase (JNK), the p38 and extracellular signal-regulated kinase (ERK)) in A549 cells treated with RY10-4. Moreover, the cytotoxic effect of RY10-4 was induction of apoptosis in A549 cells by enhancing production of reactive oxygen species (ROS). Taken together, the observations suggested that RY10-4 had affected Bcl-2 family members, caspases, MMPs, TIMPs expressions and ROS production via inhibiting STAT3 activities through ERK and p38 pathways in A549 cells. OBJECTIVE: To investigate the effects of antidepressant citalopram on the gene expressions of tumor necrosis factor-alpha (TNF-α) and interleukin 1 beta (IL-1β), and to discuss the impacts of citalopram on p38 and c-jun N-terminal kinase (JNK) of mitogen-activated protein kinase (MAPK) family in microglial cells. METHODS: BV2 cells were induced by lipopolysaccharide (LPS) to produce TNF-α and IL-1β. After pretreatment with citalopram (20 μmol/L) for 4 h, the mRNA levels of TNF-α and IL-1β were measured by quantitative real-time PCR (qRT-PCR); after pretreatment for 24 h, the protein levels of TNF-α and IL-1β were analyzed by ELISA; the effects of citalopram on the phosphorylation of p38MAPK and JNK were observed after pretreatment for 30 min. RESULTS: Citalopram significantly inhibited the mRNA and protein expressions of TNF-α and IL-1β, and the phosphorylation of p38MAPK and JNK. CONCLUSION: Citalopram may play the anti-inflammatory role by inhibiting MAPK pathway in microglial cells. Steroid hormones exert genotropic effects through members of the nuclear hormone receptor family. In the present study, we examined the effects of 17β-estradiol (E2) on nitric oxide (NO) production following lipopolysaccharide (LPS) stimulation and investigated the mechanisms in mouse bone marrow-derived macrophages (BMMs). E2 alone did not affect NO production. In contrast, E2 inhibited LPS-induced production of NO in BMMs. Using a cell-impermeable E2 conjugated to BSA (E2-BSA), which has been used to investigate the nongenomic effects of estrogen, we found that the increase in NO production induced by LPS was also attenuated. In addition, the intracellular estrogen receptor blocker, ICI 182780, only partially antagonized the total effects of E2 on LPS-stimulated NO production capacity. E2 also attenuated the LPS activation of p38 mitogen-activated protein kinase (MAPK) but not that of extracellular-regulated protein kinase 1/2 (ERK1/2) and c-Jun NH2-terminal kinase (JNK). This attenuation was not abrogated by ICI 182780. Moreover, the p38 inhibitor, SB 203580, greatly reduced the LPS-induced NO production, and the remaining NO levels were no longer regulated by E2. Additionally, E2-BSA inhibited LPS-mediated changes in p38 MAPK activation to the same extent as E2. Moreover, E2 and E2-BSA inhibited LPS-induced activation of nuclear factor-kappa B (NF-κB) and activator protein 1 (AP-1). This inhibitory effect of E2 was only partially antagonized by ICI 182780. Taken together, these results suggest that E2 has an inhibitory effect on LPS-induced NO production in BMMs through inhibition of p38 MAPK phosphorylation, and blockade of NF-κB and AP-1 activation. These effects are mediated at least in part via a nongenomic pathway.
What is the meaning of the acronym "TAILS" used in protein N-terminomics?
TAILS stands for "Terminal Amine Isotopic Labeling of Substrates"
The neutrophil-specific protease membrane-type 6 matrix metalloproteinase (MT6-MMP)/MMP-25/leukolysin is implicated in multiple sclerosis and cancer yet remains poorly characterized. To characterize the biological roles of MT6-MMP, it is critical to identify its substrates for which only seven are currently known. Here, we biochemically characterized MT6-MMP, profiled its tissue inhibitor of metalloproteinase inhibitory spectrum, performed degradomics analyses, and screened 26 chemokines for cleavage using matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry. MT6-MMP processes seven each of the CXC and CC chemokine subfamilies. Notably, cleavage of the neutrophil chemoattractant CXCL5 activates the chemokine, thereby increasing its agonist activity, indicating a feed-forward mechanism for neutrophil recruitment. Likewise, cleavage also activated CCL15 and CCL23 to increase monocyte recruitment. Utilizing the proteomics approach proteomic identification of cleavage site specificity (PICS), we identified 286 peptidic cleavage sites spanning from P6 to P6' from which an unusual glutamate preference in P1 was identified. The degradomics screen terminal amine isotopic labeling of substrates (TAILS), which enriches for neo-N-terminal peptides of cleaved substrates, was used to identify 58 new native substrates in fibroblast secretomes after incubation with MT6-MMP. Vimentin, cystatin C, galectin-1, IGFBP-7, and secreted protein, acidic and rich in cysteine (SPARC) were among those substrates we biochemically confirmed. An extracellular "moonlighting" form of vimentin is a chemoattractant for THP-1 cells, but MT6-MMP cleavage abolished monocyte recruitment. Unexpectedly, the MT6-MMP-cleaved vimentin potently stimulated phagocytosis, which was not a property of the full-length protein. Hence, MT6-MMP regulates neutrophil and monocyte chemotaxis and by generating "eat-me" signals upon vimentin cleavage potentially increases phagocytic removal of neutrophils to resolve inflammation. Proteolysis represents one of the most tightly controlled physiological processes, as proteases create events that will typically commit pathways in an irreversible manner. Despite their implication in nearly all biological systems, our understanding of the role of proteases in disease pathology is often limited. Several approaches to studying proteolytic activity as it relates to biology, pathophysiology, and drug therapy have been published, including the recently described terminal amine isotopic labeling of substrates (TAILS) strategy by Kleifeld and colleagues. Here, we investigate TAILS as a methodology based on targeted enrichment and mass spectrometric detection of endogenous N-terminal peptides from clinically relevant biological samples and its potential to provide quantitative information on proteolysis and elucidation of the protease cleavage sites. While optimizing the most current protocol, by switching to a streamlined one-tube format and simplifying the reagents' removal steps, we demonstrate the advantages over previously published methods and provide solutions to some of the technical challenges presented in the Kleifeld publication. We also identify some of the current and unresolved limitations. We use human plasma as a model system to provide data, which illustrates some of the key analytical parameters of the modified TAILS procedure, including specificity, sensitivity, quantitative precision, and accuracy. Data analysis in proteomics is complex and with the extra challenges involved in the interpretation of data from N-terminomics experiments, this can be daunting.Therefore, we have devised a rational pipeline of steps to approach N-terminomics data analysis in a statistically based and valid manner. We have automated these steps in CLIPPER, an add-on to the Trans-Proteomic Pipeline(TPP). Applying CLIPPER to the analysis of N- terminomics data generated by terminal amine isotopic labeling of substrates (TAILS) enables high confidence peptide to protein assignment, protein N-terminal characterization and annotation, and for protease analysis readily allows protease substrate discovery with high confidence.
Do mutations of AKT1 occur in meningiomas?
Yes, AKT1 mutation occurs in meningiomas.
Meningiomas are the most common primary nervous system tumor. The tumor suppressor NF2 is disrupted in approximately half of all meningiomas, but the complete spectrum of genetic changes remains undefined. We performed whole-genome or whole-exome sequencing on 17 meningiomas and focused sequencing on an additional 48 tumors to identify and validate somatic genetic alterations. Most meningiomas had simple genomes, with fewer mutations, rearrangements and copy-number alterations than reported in other tumors in adults. However, several meningiomas harbored more complex patterns of copy-number changes and rearrangements, including one tumor with chromothripsis. We confirmed focal NF2 inactivation in 43% of tumors and found alterations in epigenetic modifiers in an additional 8% of tumors. A subset of meningiomas lacking NF2 alterations harbored recurrent oncogenic mutations in AKT1 (p.Glu17Lys) and SMO (p.Trp535Leu) and exhibited immunohistochemical evidence of activation of these pathways. These mutations were present in therapeutically challenging tumors of the skull base and higher grade. These results begin to define the spectrum of genetic alterations in meningiomas and identify potential therapeutic targets. We report genomic analysis of 300 meningiomas, the most common primary brain tumors, leading to the discovery of mutations in TRAF7, a proapoptotic E3 ubiquitin ligase, in nearly one-fourth of all meningiomas. Mutations in TRAF7 commonly occurred with a recurrent mutation (K409Q) in KLF4, a transcription factor known for its role in inducing pluripotency, or with AKT1(E17K), a mutation known to activate the PI3K pathway. SMO mutations, which activate Hedgehog signaling, were identified in ~5% of non-NF2 mutant meningiomas. These non-NF2 meningiomas were clinically distinctive-nearly always benign, with chromosomal stability, and originating from the medial skull base. In contrast, meningiomas with mutant NF2 and/or chromosome 22 loss were more likely to be atypical, showing genomic instability, and localizing to the cerebral and cerebellar hemispheres. Collectively, these findings identify distinct meningioma subtypes, suggesting avenues for targeted therapeutics. 1. Cancer Discov. 2013 Mar;3(3):OF13. doi: 10.1158/2159-8290.CD-RW2013-028. Epub 2013 Feb 7. Meningiomas arise from the arachnoid layer of the meninges that surround the brain and spine. They account for over one third of all primary central nervous system tumors in adults and confer a significant risk of location-dependent morbidity due to compression or displacement. A significant increase in risk of meningiomas is associated with neurofibromatosis type 2 (NF2) disease through mutation of the NF2 gene. In addition, approximately 5% of individuals with schwannomatosis disease develop meningiomas, through mutation of the SWI/SNF chromatin remodeling complex subunit, SMARCB1. Recently, a second SWI/SNF complex subunit, SMARCE1, was identified as a cause of clear cell meningiomas, indicating a wider role for this complex in meningioma disease. The sonic hedgehog (SHH)-GLI1 signaling pathway gene, SUFU, has also been identified as the cause of hereditary multiple meningiomas in a large Finnish family. The recent identification of somatic mutations in components of the SHH-GLI1 and AKT1-MTOR signaling pathways indicates the potential for cross talk of these pathways in the development of meningiomas. This review describes the known meningioma predisposition genes and their links to the recently identified somatic mutations.
What are the main indications of lacosamide?
Lacosamide is an anti-epileptic drug, licensed for refractory partial-onset seizures. In addition to this, it has demonstrated analgesic activity in various animal models. Apart from this, LCM has demonstrated potent effects in animal models for a variety of CNS disorders like schizophrenia and stress induced anxiety.
This paper comprises a series of experiments in rodent models of partial and generalized epilepsy which were designed to describe the anti-convulsant profile of the functionalized amino acid lacosamide. Lacosamide was effective against sound-induced seizures in the genetically susceptible Frings mouse, against maximal electroshock test (MES)-induced seizures in rats and mice, in the rat hippocampal kindling model of partial seizures, and in the 6Hz model of psychomotor seizures in mice. The activity in the MES test in both mice (4.5mg/kg i.p.) and rats (3.9 mg/kg p.o.) fell within the ranges previously reported for most clinically available anti-epileptic drugs. At both the median effective dose for MES protection, as well as the median toxic dose for rotorod impairment, lacosamide elevated the seizure threshold in the i.v. pentylenetetrazol seizure test, suggesting that it is unlikely to be pro-convulsant at high doses. Lacosamide was inactive against clonic seizures induced by subcutaneous administration of the chemoconvulsants pentylenetetrazol, bicuculline, and picrotoxin, but it did inhibit NMDA-induced seizures in mice and showed full efficacy in the homocysteine model of epilepsy. In summary, the overall anti-convulsant profile of lacosamide appeared to be unique, and the drug displayed a good margin of safety in those tests in which it was effective. These results suggest that lacosamide may have the potential to be clinically useful for at least the treatment of generalized tonic-clonic and partial-onset epilepsies, and support ongoing clinical trials in these indications. Lacosamide (LCM), (SPM 927, (R)-2-acetamido-N-benzyl-3-methoxypropionamide, previously referred to as harkoseride or ADD 234037) is a member of a series of functionalized amino acids that were specifically synthesized as anticonvulsive drug candidates. LCM has demonstrated antiepileptic effectiveness in different rodent seizure models and antinociceptive potential in experimental animal models that reflect distinct types and symptoms of neuropathic as well as chronic inflammatory pain. Recent results suggest that LCM has a dual mode of action underlying its anticonvulsant and analgesic activity. It was found that LCM selectively enhances slow inactivation of voltage-gated sodium channels without affecting fast inactivation. Furthermore, employing proteomic affinity-labeling techniques, collapsin-response mediator protein 2 (CRMP-2 alias DRP-2) was identified as a binding partner. Follow-up experiments confirmed a functional interaction of LCM with CRMP-2 in vitro. LCM did not inhibit or induce a wide variety of cytochrome P450 enzymes at therapeutic concentrations. In safety pharmacology and toxicology studies conducted in mice, rats, rabbits, and dogs, LCM was well tolerated. Either none or only minor side effects were observed in safety studies involving the central nervous, respiratory, gastrointestinal, and renal systems and there is no indication of abuse liability. Repeated dose toxicity studies demonstrated that after either intravenous or oral administration of LCM the adverse events were reversible and consisted mostly of exaggerated pharmacodynamic effects on the CNS. No genotoxic or carcinogenic effects were observed in vivo, and LCM showed a favorable profile in reproductive and developmental animal studies. Currently, LCM is in a late stage of clinical development as an adjunctive treatment for patients with uncontrolled partial-onset seizures, and it is being assessed as monotherapy in patients with painful diabetic neuropathy. Further trials to identify LCM's potential in pain and for other indications have been initiated. Collapsin response mediator protein-2 (DPYSL2 or CRMP2) is a multifunctional adaptor protein within the central nervous system. In the developing brain or cell cultures, CRMP2 performs structural and regulatory functions related to cytoskeletal dynamics, vesicle trafficking and synaptic physiology whereas CRMP2 functions in adult brain are still being elucidated. CRMP2 has been associated with several neuropathologic or psychiatric conditions including Alzheimer's disease (AD) and schizophrenia, either at the level of genetic polymorphisms; protein expression; post-translational modifications; or protein/protein interactions. In AD, CRMP2 is phosphorylated by glycogen synthase kinase-3β (GSK3β) and cyclin dependent protein kinase-5 (CDK5), the same kinases that act on tau protein in generating neurofibrillary tangles (NFTs). Phosphorylated CRMP2 collects in NFTs in association with the synaptic structure-regulating SRA1/WAVE1 (specifically Rac1-associated protein-1/WASP family verprolin-homologous protein-1) complex. This phenomenon could plausibly contribute to deficits in neural and synaptic structure that have been well documented in AD. This review discusses the essential biology of CRMP2 in the context of nascent data implicating CRMP2 perturbations as either a correlate of, or plausible contributor to, diverse neuropathologies. A discussion is made of recent findings that the atypical antidepressant tianeptine increases CRMP2 expression, whereas other, neuroactive small molecules including the epilepsy drug lacosamide and the natural brain metabolite lanthionine ketimine appear to bind CRMP2 directly with concomitant affects on neural structure. These findings constitute proofs-of-concept that pharmacological manipulation of CRMP2 is possible and hence, may offer new opportunities for therapy development against certain neurological diseases. PURPOSE OF REVIEW: There is a need for newer anti-epileptic drugs (AEDs) with improved efficacy and tolerability. This article reviews AEDs introduced since 2007 and investigational compounds in clinical development. RECENT FINDINGS: Two recently introduced AEDs, stiripentol and rufinamide, have been licensed exclusively for orphan indications, that is severe myoclonic epilepsy of infancy (stiripentol, Europe) and Lennox-Gastaut syndrome (rufinamide, Europe and the USA). This signals a welcome new trend to explore novel treatments in specific pediatric syndromes for which there are high therapeutic needs. Two additional AEDs, lacosamide and eslicarbazepine acetate, have been licensed recently for a more traditional indication, refractory partial-onset seizures. Although newly introduced agents given as adjunctive therapy have been found to be superior to placebo in reducing seizure frequency, the ultimate goal of sustained seizure freedom is rarely achieved. Therefore, the search for better agents should continue. Several investigational compounds are currently in various stages of clinical development. SUMMARY: The recent introduction of newer AEDs has enlarged the armamentarium against epilepsy. However, newer agents had only a modest impact on the probability of achieving long-term remission. Novel strategies for the discovery and development of truly innovative AEDs are sorely needed. Blood (serum/plasma) antiepileptic drug (AED) therapeutic drug monitoring (TDM) has proven to be an invaluable surrogate marker for individualizing and optimizing the drug management of patients with epilepsy. Since 1989, there has been an exponential increase in AEDs with 23 currently licensed for clinical use, and recently, there has been renewed and extensive interest in the use of saliva as an alternative matrix for AED TDM. The advantages of saliva include the fact that for many AEDs it reflects the free (pharmacologically active) concentration in serum; it is readily sampled, can be sampled repetitively, and sampling is noninvasive; does not require the expertise of a phlebotomist; and is preferred by many patients, particularly children and the elderly. For each AED, this review summarizes the key pharmacokinetic characteristics relevant to the practice of TDM, discusses the use of other biological matrices with particular emphasis on saliva and the evidence that saliva concentration reflects those in serum. Also discussed are the indications for salivary AED TDM, the key factors to consider when saliva sampling is to be undertaken, and finally, a practical protocol is described so as to enable AED TDM to be applied optimally and effectively in the clinical setting. Overall, there is compelling evidence that salivary TDM can be usefully applied so as to optimize the treatment of epilepsy with carbamazepine, clobazam, ethosuximide, gabapentin, lacosamide, lamotrigine, levetiracetam, oxcarbazepine, phenobarbital, phenytoin, primidone, topiramate, and zonisamide. Salivary TDM of valproic acid is probably not helpful, whereas for clonazepam, eslicarbazepine acetate, felbamate, pregabalin, retigabine, rufinamide, stiripentol, tiagabine, and vigabatrin, the data are sparse or nonexistent. Network analysis is an emerging tool for the study of complex systems. Antiepileptic drug (AED) polytherapy in children with medically intractable epilepsy may be considered a complex system, given the heterogeneity of drug combinations that are frequently modified according to clinical indications. The current article presents a concise review of network theory and its application to the characterization of AED use in children with refractory epilepsy. Current and previous AEDs prescribed to 27 children with refractory, localization-related epilepsy were recorded, and network theory was applied to identify patterns of drug administration. Of the fifteen unique AEDs prescribed, levetiracetam possessed the highest betweenness centrality within the network. Furthermore, first generation AEDs were often discontinued, while lacosamide and topiramate were most likely to be initiated. We also identified three subnetworks of AEDs that were commonly coadministered. We conclude that network analysis is an effective method to characterize the complexity of AED administration patterns in children with epilepsy with many promising future applications.
Which fusion protein is involved in the development of Ewing sarcoma?
Ewing sarcoma is the second most common bone malignancy in children and young adults. In almost 95% of the cases, it is driven by oncogenic fusion protein EWS/FLI1, which acts as an aberrant transcription factor, that upregulates or downregulates target genes, leading to cellular transformation.
The Ewing family of tumors harbors chromosomal translocations that join the N-terminal region of the EWS gene with the C-terminal region of several transcription factors of the ETS family, mainly FLI1, resulting in chimeric transcription factors that play a pivotal role in the pathogenesis of Ewing tumors. To identify downstream targets of the EWS/FLI1 fusion protein, we established 293 cells expressing constitutively either the chimeric EWS/FLI1 or wild type FLI1 proteins and used cDNA arrays to identify genes differentially regulated by EWS/FLI1. DAX1 (NR0B1), an unusual orphan nuclear receptor involved in gonadal development, sex determination and steroidogenesis, showed a consistent up-regulation by EWS/FLI1 oncoprotein, but not by wild type FLI1. Specific induction of DAX1 by EWS/FLI1 was confirmed in two independent cell systems with inducible expression of EWS/FLI1. We also analyzed the expression of DAX1 in Ewing tumors and derived cell lines, as well as in other nonrelated small round cell tumors. DAX1 was expressed in all Ewing tumor specimens analyzed, and in seven out of eight Ewing tumor cell lines, but not in any neuroblastoma or embryonal rhabdomyosarcoma. Furthermore, silencing of EWS/FLI1 by RNA interference in a Ewing tumor cell line markedly reduced the levels of DAX1 mRNA and protein, confirming that DAX1 up-regulation is dependent upon EWS/FLI1 expression. The high levels of DAX1 found in Ewing tumors and its potent transcriptional repressor activity suggest that the oncogenic effect of EWS/FLI1 may be mediated, at least in part, by the up-regulation of DAX1 expression. Our understanding of Ewing's sarcoma development mediated by the EWS/FLI fusion protein has been limited by a lack of knowledge regarding the tumor cell of origin. To circumvent this, we analyzed the function of EWS/FLI in Ewing's sarcoma itself. By combining retroviral-mediated RNA interference with reexpression studies, we show that ongoing EWS/FLI expression is required for the tumorigenic phenotype of Ewing's sarcoma. We used this system to define the full complement of EWS/FLI-regulated genes in Ewing's sarcoma. Functional analysis revealed that NKX2.2 is an EWS/FLI-regulated gene that is necessary for oncogenic transformation in this tumor. Thus, we developed a highly validated transcriptional profile for the EWS/FLI fusion protein and identified a critical target gene in Ewing's sarcoma development. Sarcomas account for less than 10% of all human maligcies that are believed to originate from as yet poorly defined mesenchymal progenitor cells. They constitute some of the most aggressive adult and childhood cancers in that they have a high metastatic proclivity and are typically refractory to conventional chemo- and radiation therapy. Ewing's sarcoma is a member of Ewing's family tumors (ESFT) and the second most common solid bone and soft tissue maligcy of children and young adults. It is associated in 85% of cases with the t(11;22)(q24:q12) chromosomal translocation that generates fusion of the 5' segment of the EWS gene with the 3' segment of the ETS family gene FLI-1. The resulting EWS-FLI-1 fusion protein is believed to behave as an aberrant transcriptional activator that contributes to ESFT development by altering the expression of its target genes in a permissive cellular environment. Although ESFTs are among the best studied sarcomas, the mechanisms involved in EWS-FLI-1-induced transformation require further elucidation and the primary cells from which ESFTs originate need to be identified. This review will highlight some of the most recent discoveries in the field of Ewing sarcoma biology and origins. Ewing sarcoma/primitive neuroectodermal tumors (EWS/PNET) are characterized by specific chromosomal translocations most often generating a chimeric EWS/FLI-1 gene. Depending on the number of juxtaposed exons assembled, several fusion types have been described with different incidences and prognoses. To assess the impact of each fusion type on the specific phenotypic, tumorigenic, and metastatic features of EWS/PNET, we developed an amenable system using a murine mesenchymal multipotent C3H10T1/2 cell line. Upon transduction of EWS/FLI-1, cells acquired dramatic morphological changes in vitro, including a smaller size and "neurite-like" membrane elongations. Chimeric fusion proteins conferred oncogenic properties in vitro, including anchorage-independent growth and an increased rate of proliferation. Furthermore, EWS/FLI-1 expression blocked mineralization, with concomitant repression of osteoblastic genes, and induced a dramatic repression of the adipocytic differentiation program. Moreover, EWS/FLI-1 promoted an aberrant neural phenotype by the de novo expression of specific neural genes. The intramuscular injection of transduced cells led to tumor development and the induction of overt osteolytic lesions. Analogously, to what was observed in human tumors, type 2 EWS/FLI-1 cells formed primary tumors in immunodeficient mice with a higher incidence and a lower latency than cells bearing types 1 and 3 fusions. By contrast, cells expressing types 2 and 3 fusions showed specific metastatic activity with a higher number of macroscopic metastases in soft tissues and osteolytic lesions in the limbs as compared to type-1-expressing cells. Therefore, the structure of each oncoprotein strongly influenced its tumorigenicity and metastagenicity. Thus, this model provides a basis for understanding the genetic determits involved in Ewing tumor development and metastatic activity and represents a cellular system to analyze other oncoproteins involved in human sarcomagenesis. Ewing's sarcomas are characterized by recurrent chromosomal translocations expressing EWS-ETS fusion proteins, the most common of which is EWS-FLI.(1-5) EWS-FLI is an oncogenic transcription factor that regulates genes involved in tumorigenesis.(6,7) Because the Ewing's sarcoma cell of origin remains unknown, a variety of model systems have been developed to study EWS-FLI fusions,(8-14) and multiple microarray experiments describing potential EWS-FLI target genes have been reported.(8,10,11,13,15-21) Each model has potential benefits and drawbacks, but a large-scale comparison of these has not been reported. Herein we report a meta-analysis of the genes that are dysregulated by EWS-FLI in Ewing's sarcoma model systems. In general, EWS-FLI gain- and loss-of-function models in human cell types were well correlated to patient-derived tumor samples, while murine models were not. Using frequency analysis of dysregulated genes across multiple model systems, we identified a conserved "core" EWS-FLI transcriptional signature. This signature contained many of the genes known to be involved in the tumorigenic phenotype of Ewing's sarcoma, and also contained genes that have not been previously reported. Comparisons between the core EWS-FLI signature and published mesenchymal stem cell data support the recent assertion that mesenchymal stem cells are likely the Ewing's sarcoma precursor cell.(15) These results demonstrate the utility of using comparative analysis to validate model systems and emphasize the unique potential of this approach to identify both oncogenic and background cell signatures. Ewing's tumour is the second most frequent primary tumour of bone. It is associated in 85% of cases with a specific and recurrent chromosome translocation, a t(11; 22)(q24; q12) which generates a fusion gene between the 5' part of EWS and the 3' part of FLI-1, a member of the ETS family. Less frequently, this gene fusion involves EWS and another member of the ETS family which can be: ERG, ETV1, E1AF or FEV depending on the cases. The EWS-ETS fusion is causative in the development of Ewing's tumour. Its mechanism of action mainly relies on the abnormal transcription regulation of key target genes which are involved in the regulation of cell cycle, signal transduction, migration. The cellular context within which EWS-FLI-1 exerts its oncogenic action is a long standing matter of debate. Recent data converge to suggest that the Ewing cell origin is a mesenchymal stem cell. Ewing's sarcoma is a maligt bone-associated tumor of children and young adults. Most cases of Ewing's sarcoma express the EWS/FLI fusion protein. EWS/FLI functions as an aberrant ETS-type transcription factor and serves as the master regulator of Ewing's sarcoma-transformed phenotype. We recently showed that EWS/FLI regulates one of its key targets, NR0B1, through a GGAA-microsatellite in its promoter. Whether other critical EWS/FLI targets are also regulated by GGAA-microsatellites was unknown. In this study, we combined transcriptional analysis, whole genome localization data, and RNA interference knockdown to identify glutathione S-transferase M4 (GSTM4) as a critical EWS/FLI target gene in Ewing's sarcoma. We found that EWS/FLI directly binds the GSTM4 promoter, and regulates GSTM4 expression through a GGAA-microsatellite in its promoter. Reduction of GSTM4 levels caused a loss of oncogenic transformation. Furthermore, reduction of GSTM4 resulted in an increased sensitivity of Ewing's sarcoma cells to chemotherapeutic agents, suggesting a role for this protein in drug resistance. Consistent with this hypothesis, patients with Ewing's sarcoma whose tumors had higher levels of GSTM4 expression had worse outcomes than those with lower expression levels. These data show that GSTM4 contributes to the cancerous behavior of Ewing's sarcoma and define a wider role for GGAA-microsatellites in EWS/FLI function than previously appreciated. These data also suggest a novel therapeutic resistance mechanism, in which the central oncogenic abnormality directly regulates a resistance gene. Ewing sarcoma family of tumors (ESFT) is a group of aggressive pediatric maligcies driven by the EWS-FLI1 fusion protein, an aberrant transcription factor up-regulating specific target genes, such as neuropeptide Y (NPY) and its Y1 and Y5 receptors (Y5Rs). Previously, we have shown that both exogenous NPY and endogenous NPY stimulate ESFT cell death via its Y1 and Y5Rs. Here, we demonstrate that this effect is prevented by dipeptidyl peptidases (DPPs), which cleave NPY to its shorter form, NPY(3-36), not active at Y1Rs. We have shown that NPY-induced cell death can be abolished by overexpression of DPPs and enhanced by their down-regulation. Both NPY treatment and DPP blockade activated the same cell death pathway mediated by poly(ADP-ribose) polymerase (PARP-1) and apoptosis-inducing factor (AIF). Moreover, the decrease in cell survival induced by DPP inhibition was blocked by Y1 and Y5R antagonists, confirming its dependence on endogenous NPY. Interestingly, similar levels of NPY-driven cell death were achieved by blocking membrane DPPIV and cytosolic DPP8 and DPP9. Thus, this is the first evidence of these intracellular DPPs cleaving releasable peptides, such as NPY, in live cells. In contrast, another membrane DPP, fibroblast activation protein (FAP), did not affect NPY actions. In conclusion, DPPs act as survival factors for ESFT cells and protect them from cell death induced by endogenous NPY. This is the first demonstration that intracellular DPPs are involved in regulation of ESFT growth and may become potential therapeutic targets for these tumors. Ewing's sarcoma, a maligt bone tumor of children and young adults, is a member of the small-round-blue-cell tumor family. Ewing's sarcoma family tumors (ESFTs), which include peripheral primitive neuroectodermal tumors (PNETs), are characterized by chromosomal translocations that generate fusions between the EWS gene and ETS-family transcription factors, most commonly FLI1. The EWS-FLI1 fusion oncoprotein represents an attractive therapeutic target for treatment of Ewing's sarcoma. The cell of origin of ESFT and the molecular mechanisms by which EWS-FLI1 mediates tumorigenesis remain unknown, and few animal models of Ewing's sarcoma exist. Here, we report the use of zebrafish as a vertebrate model of EWS-FLI1 function and tumorigenesis. Mosaic expression of the human EWS-FLI1 fusion protein in zebrafish caused the development of tumors with histology strongly resembling that of human Ewing's sarcoma. The incidence of tumors increased in a p53 mutant background, suggesting that the p53 pathway suppresses EWS-FLI1-driven tumorigenesis. Gene expression profiling of the zebrafish tumors defined a set of genes that might be regulated by EWS-FLI1, including the zebrafish ortholog of a crucial EWS-FLI1 target gene in humans. Stable zebrafish transgenic lines expressing EWS-FLI1 under the control of the heat-shock promoter exhibit altered embryonic development and defective convergence and extension, suggesting that EWS-FLI1 interacts with conserved developmental pathways. These results indicate that functional targets of EWS-FLI1 that mediate tumorigenesis are conserved from zebrafish to human and provide a novel context in which to study the function of this fusion oncogene. Ewing sarcoma family tumors (ESFT) are highly aggressive and highly metastatic tumors caused by a chromosomal fusion between the Ewing sarcoma protein (EWS) with the transcription factor FLI-1. However, expression of the EWS/FLI-1 chimeric oncogene by itself is insufficient for carcinogenesis, suggesting that additional events are required. Here, we report the identification of the Akt substrate PRAS40 as an EWS target gene. EWS negatively regulates PRAS40 expression by binding the 3' untranslated region in PRAS40 mRNA. ESFT cell proliferation was suppressed by treatment with an Akt inhibitor, and ESFT cell proliferation and metastatic growth were suppressed by siRNA-mediated PRAS40 knockdown. Furthermore, PRAS40 knockdown was sufficient to reverse an increased cell proliferation elicited by EWS knockdown. In support of a pathologic role for PRAS40 elevation in EFST, we documented inverse protein levels of EWS and PRAS40 in ESFT cells. Together, our findings suggest that PRAS40 promotes the development of ESFT and might therefore represent a novel therapeutic target in this aggressive disease. Ewing sarcoma is an aggressive pediatric cancer of the bone and soft tissue, in which patients whose tumors have a poor histologic response to initial chemotherapy have a poor overall prognosis. Therefore, it is important to identify molecules involved in resistance to chemotherapy. Herein, we show that the DNA repair protein and transcriptional cofactor, EYA3, is highly expressed in Ewing sarcoma tumor samples and cell lines compared with mesenchymal stem cells, the presumed cell-of-origin of Ewing sarcoma, and that it is regulated by the EWS/FLI1 fusion protein transcription factor. We further show that EWS/FLI1 mediates upregulation of EYA3 via repression of miR-708, a miRNA that targets the EYA3 3'-untranslated region, rather than by binding the EYA3 promoter directly. Importantly, we show that high levels of EYA3 significantly correlate with low levels of miR-708 in Ewing sarcoma samples, suggesting that this miR-mediated mechanism of EYA3 regulation holds true in human cancers. Because EYA proteins are important for cell survival during development, we examine, and show, that loss of EYA3 decreases survival of Ewing sarcoma cells. Most importantly, knockdown of EYA3 in Ewing sarcoma cells leads to sensitization to DNA-damaging chemotherapeutics used in the treatment of Ewing sarcoma, and as expected, after chemotherapeutic treatment, EYA3 knockdown cells repair DNA damage less effectively than their control counterparts. These studies identify EYA3 as a novel mediator of chemoresistance in Ewing sarcoma and define the molecular mechanisms of both EYA3 overexpression and of EYA3-mediated chemoresistance. Ewing sarcoma is the second most common bone maligcy in children and young adults. It is driven by oncogenic fusion proteins (i.e. EWS/FLI1) acting as aberrant transcription factors that upregulate and downregulate target genes, leading to cellular transformation. Thus, identificating these target genes and understanding their contribution to Ewing sarcoma tumorigenesis are key for the development of new therapeutic strategies. In this study we show that lysyl oxidase (LOX), an enzyme involved in maintaining structural integrity of the extracellular matrix, is downregulated by the EWS/FLI1 oncoprotein and in consequence it is not expressed in Ewing sarcoma cells and primary tumors. Using a doxycycline inducible system to restore LOX expression in an Ewing sarcoma derived cell line, we showed that LOX displays tumor suppressor activities. Interestingly, we showed that the tumor suppressor activity resides in the propeptide domain of LOX (LOX-PP), an N-terminal domain produced by proteolytic cleavage during the physiological processing of LOX. Expression of LOX-PP reduced cell proliferation, cell migration, anchorage-independent growth in soft agar and formation of tumors in immunodeficient mice. By contrast, the C-terminal domain of LOX, which contains the enzymatic activity, had the opposite effects, corroborating that the tumor suppressor activity of LOX is mediated exclusively by its propeptide domain. Finally, we showed that LOX-PP inhibits ERK/MAPK signalling pathway, and that many pathways involved in cell cycle progression were significantly deregulated by LOX-PP, providing a mechanistic explanation to the cell proliferation inhibition observed upon LOX-PP expression. In summary, our observations indicate that deregulation of the LOX gene participates in Ewing sarcoma development and identify LOX-PP as a new therapeutic target for one of the most aggressive paediatric maligcies. These findings suggest that therapeutic strategies based on the administration of LOX propeptide or functional analogues could be useful for the treatment of this devastating paediatric cancer. Fusion of the EWS gene to FLI1 produces a fusion oncoprotein that drives an aberrant gene expression program responsible for the development of Ewing sarcoma. We used a homogenous proximity assay to screen for compounds that disrupt the binding of EWS-FLI1 to its cognate DNA targets. A number of DNA-binding chemotherapeutic agents were found to non-specifically disrupt protein binding to DNA. In contrast, actinomycin D was found to preferentially disrupt EWS-FLI1 binding by comparison to p53 binding to their respective cognate DNA targets in vitro. In cell-based assays, low concentrations of actinomycin D preferentially blocked EWS-FLI1 binding to chromatin, and disrupted EWS-FLI1-mediated gene expression. Higher concentrations of actinomycin D globally repressed transcription. These results demonstrate that actinomycin D preferentially disrupts EWS-FLI1 binding to DNA at selected concentrations. Although the window between this preferential effect and global suppression is too narrow to exploit in a therapeutic manner, these results suggest that base-preferences may be exploited to find DNA-binding compounds that preferentially disrupt subclasses of transcription factors. EWS-FLI1 is an oncogenic fusion protein implicated in the development of Ewing's sarcoma family tumors (ESFT). Using our previously reported lead compound 2 (YK-4-279), we designed and synthesized a focused library of analogues. The functional inhibition of the analogues was measured by an EWS-FLI1/NR0B1 reporter luciferase assay and a paired cell screening approach measuring effects on growth inhibition for human cells containing EWS-FLI1 (TC32 and TC71) and control PANC1 cell lines devoid of the oncoprotein. Our data revealed that substitution of electron donating groups at the para-position on the phenyl ring was the most favorable for inhibition of EWS-FLI1 by analogs of 2. Compound 9u (with a dimethylamino substitution) was the most active inhibitor with GI50 = 0.26 ± 0.1 μM. Further, a correlation of growth inhibition (EWS-FLI1 expressing TC32 cells) and the luciferase reporter activity was established (R(2) = 0.84). Finally, we designed and synthesized a biotinylated analogue and determined the binding affinity for recombit EWS-FLI1 (Kd = 4.8 ± 2.6 μM). Ewing sarcoma is a maligt bone cancer that primarily occurs in children and adolescents. Eighty-five percent of Ewing sarcoma is characterized by the presence of the aberrant chimeric EWS/FLI1 fusion gene. Previously, we demonstrated that an interaction between EWS/FLI1 and wild-type EWS led to the inhibition of EWS activity and mitotic dysfunction. Although defective mitosis is considered to be a critical step in cancer initiation, it is unknown how interference with EWS contributes to Ewing sarcoma formation. Here, we demonstrate that EWS/FLI1- and EWS-knockdown cells display a high incidence of defects in the midzone, a midline structure located between segregating chromatids during anaphase. Defects in the midzone can lead to the failure of cytokinesis and can result in the induction of aneuploidy. The similarity among the phenotypes of EWS/FLI1- and EWS siRNA-transfected HeLa cells points to the inhibition of EWS as the key mechanism for the induction of midzone defects. Supporting this observation, the ectopic expression of EWS rescues the high incidence of midzone defects observed in Ewing sarcoma A673 cells. We discovered that EWS interacts with Aurora B kinase, and that EWS is also required for recruiting Aurora B to the midzone. A domain analysis revealed that the R565 in the RGG3 domain of EWS is essential for both Aurora B interaction and the recruitment of Aurora B to the midzone. Here, we propose that the impairment of EWS-dependent midzone formation via the recruitment of Aurora B is a potential mechanism of Ewing sarcoma development.
List Hemolytic Uremic Syndrome Triad.
Hemolytic uremic syndrome (HUS) is a clinical syndrome characterized by the triad of anaemia, thrombocytopenia, renal failure.
Hemolytic uremic syndrome is a rare entity in patients with carcinoma and presents with a triad of renal insufficiency, microangiopathic hemolytic anemia, and thrombocytopenia. We report this syndrome for the first time in a patient with small cell lung carcinoma. Spontaneous platelet aggregation of washed normal platelets was demonstrated using patient plasma. Circulating immune complex levels were not elevated. The entity completely resolved after treatment with plasma, vincristine, aspirin, and dipyridamole. The hemolytic-uremic syndrome is a pathology characterized by a triad consisting of acute renal failure, microangiopathic hemolytic anemia and thrombocytopenia, with complications of the central nervous system arising in a considerable number of cases. Altered cranial computerized tomography examinations usually reveal cerebral infarctions. We present here two cases in which diffuse hypodensity was observed in the white matter in addition to the infarcts. This hypodensity was reversible after resolution of the acute phase of the disease, as is also the case for the alterations described in uremic encephalopathy and in hypertensive encephalopathy of other etiologies. Acute renal insufficiency in the setting of hemolysis and thrombocytopenia, a triad that constitutes adult or pediatric hemolytic uremic syndrome, can be associated with or triggered by diverse conditions such as verocytotoxin-producing Escherichia coli, viral infections, pregcy, maligt hypertension, scleroderma, renal radiation, allograft rejection, lupus erythematosus, and assorted medications such as mitomycin C, cyclosporine, and oral contraceptives. Recurrent and de novo hemolytic uremic syndrome occur after renal transplantation. Relapses are also common and probably reflect incomplete resolution of the initial episode. The major differential diagnoses of hemolytic uremic syndrome in the renal allograft include acute vascular rejection, cyclosporine, FK506 or antilymphocyte antibody nephrotoxicity, and maligt hypertension, all of which may display overlapping clinical and histologic features with primary hemolytic uremic syndrome; in such instances, the exact diagnosis may be quite difficult. It is possible that the risk of recurrence may be reduced by proper timing of transplantation and suitable choice of immunosuppressive agents. Intensive plasmapheresis in conjunction with fresh frozen plasma and supportive management of renal failure may lessen mortality and morbidity even in recurrent hemolytic uremic syndrome after transplantation. CONTEXT: Hemolytic uremic syndrome is a rare condition compromising the clinical triad of acute renal failure, microangiopathic hemolytic anemia, and thrombocytopenia. Hemolytic uremic syndrome may be associated with a variety of etiologies, and chemotherapeutic agents have also been reported to be associated with hemolytic uremic syndrome, including mitomycin, cisplatin, bleomycin, and most recently gemcitabine. CASE REPORT: A 72-year-old Caucasian male treated with four cycles of gemcitabine at 1,000 mg/m2 developed clinical and laboratory findings compatible with hemolytic uremic syndrome. He developed microangiopathic hemolysis, rapidly declining renal function with proteinuria and hematuria, and renal biopsy revealed thrombotic microangiopathy. Hemodialysis, plasmapheresis, and corticosteroid therapy were utilized but the process ultimately was irreversible. CONCLUSION: With multiple reports of hemolytic uremic syndrome complicating gemcitabine therapy, it is imperative that clinicians heighten their awareness of this potentially lethal complication. Hemolytic uremic syndrome (HUS) is a triad of microangiopathic hemolytic anemia, thrombocytopenia, and acute renal failure. HUS is classified as either diarrhea associated, most commonly caused by infection with Escherichia coli O157, or the less common atypical HUS (aHUS), which may be familial or sporadic. Approximately 50% of patients with aHUS have mutations in one of the complement control proteins: factor H, factor I, or membrane cofactor protein (MCP). These proteins regulate complement activation through cofactor activity, the inactivation of C3b by limited proteolytic cleavage, a desirable event in the fluid phase (no target) or on healthy self-tissue (wrong target). Complement activation follows the endothelial cell injury that characterizes HUS. This disease represents a model of what takes place when inappropriate complement activation occurs on self-tissues due to the presence of mutated complement regulatory proteins. Screening for mutations in factor H, factor I, or MCP is expensive and time consuming. One approach is to perform antigenic screening for factor H and factor I deficiency and to look for low levels of MCP (CD46) expression by flow cytometry. Complement regulatory protein deficiency impacts treatment decisions as patients with aHUS have a recurrence rate in renal transplants of approximately 50%, whereas those with factor H mutations have an even higher risk (approximately 80%). By contrast, MCP deficiency can be corrected in part by a renal allograft. However, caution in the use of live-related donations is needed because of the high rates of incomplete penetrance of the described mutations. Hemolytic uremic syndrome is a triad of microangiopathic hemolytic anemia, thrombocytopenia, and acute renal failure. It is one of a group of conditions termed the thrombotic microangiopathies, which are characterized by prominent endothelial cell injury. It may be diarrheal-associated or atypical (aHUS). Evidence for a pathogenic role of the alternative pathway of complement was first suggested in 1974. Mutations in the complement regulatory proteins factor H, membrane cofactor protein (CD46), and factor I predispose to aHUS development. Mutations of the activating components factor B and complement C3 have also been reported. Penetrance is approximately 50%, suggesting other genetic and environmental modifiers are needed for disease expression. Identification of mutations is important owing to differences in mortality, renal survival, and outcome of renal transplantation. Current treatment is plasma infusion/exchange, but complement inhibitor therapy provides hope for the future. Hemolytic Uremic Syndrome (HUS) consists ofa triad of acquired hemolytic anemia, thrombocytopenia, and renal failure that occurs acutely in otherwise healthy individuals. HUS may be divided into two broad categories, typical, preceded by a diarrheal prodrome, and atypical. The clinical symptoms of HUS as well as its course, prognosis, and response to treatment appear to be significantly influenced by a number of factors, including age at onset, type and severity of underlying infections, and/or systemic diseases. A retrospective case series review of five patients diagnosed with Hemolytic Uremic Syndrome at the Pediatric University Hospital in Puerto Rico between 1997-2007 was performed. The study showed that the incidence of HUS in children in Puerto Rico is lower than other countries. However, the majority of cases have an atypical presentation, which places our patients at higher risk for life-threatening complications. BACKGROUND: Hemolytic uremic syndrome, one of the common causes of acute renal failure in children, is characterized by the triad of microangiopathy, haemolytic anemia, thrombocytopenia and acute renal failure. The diarrhoea-associated Hemolytic uremic syndrome is usually termed as a typical Hemolytic uremic syndrome. Streptococcus pneumoniae is an uncommon etiological pathogen for inducing Hemolytic uremic syndrome, and Streptococcus pneumoniae associated Hemolytic uremic syndrome is also termed as atypical hemolytic uremic syndrome. AIM: to report two pediatric cases of invasive S pneumoniae complicated with hemolytic uremic syndrome HUS. CASE REPORT: The first patient presented with pneumococcal pneumonia and empyema and the second patient presented with pneumococcal pneumonia and meningitis. The two patients were under one year of age and required peritoneal dialysis with improvement of renal function in one; the other died. CONCLUSION: Pneumococcal invasive disease may be a cause of severe HUS, so a high index of suspicion is mandatory to prompt appropriate diagnosis and management. BACKGROUND: Hemolytic uremic syndrome consists of a triad of acquired hemolytic anemia, thrombocytopenia and renal failure. AIM: Our objectives were to determine epidemiology, clinical and laboratory characteristics of patients with atypical hemolytic uremic syndrome (aHUS) to determine the relationship between the complement protein deficit and aHUS in the Tunisian population. METHODS: We studied retrospectively four cases of atypical HUS in adults admitted in the Nephrology Department of Fattouma Bourguiba Universitary Hospital in Monastir between 2000 and 2008. RESULTS: Three patients had renal failure that required dialysis. One of them received kidney transplantation with no further recurrence of aHUS. Three patients had normal C3, C4, CFH, and FB levels, and in all patients anti-FH autoantibodies were absent. The kidney biopsy of one patient showed in addition to lupus glomerulonephritis histological findings consistent with TMA. A decrease in C3, C4 and CFH levels in this patient was found both before and after the cure. CONCLUSION: Nephrologists should be aware of autoimmune conditions and genetic abnormalities of the complement regulatory genes as possible pathogenic mechanisms in atypical HUS patients. Hemolytic uremic syndrome (HUS) is a severe disease characterized by the clinical triad of hemolytic anemia, thrombocytopenia, and acute renal failure. HUS exists in two forms: the atypical diarrhea-negative HUS, which is often associated with complement disorders, and the more frequent diarrheal-associated typical HUS, which is caused by infections with enterohemorrhagic ESCHERICHIA COLI. The virulence factors of the latter have been studied well, and Shiga toxin (Stx)2 is reported to represent the most important one. In contrast, risk factors on the host side have not been intensively studied until recently: Complement activation products have been detected in the serum and plasma of HUS patients, and an in vitro study could show that Stx2 not only damages the kidney directly but also indirectly via complement, in two ways. First, it activates complement, and second, it delays the functions of its control protein factor H on the cell surface, both known to damage the kidney. BACKGROUND: Atypical hemolytic uremic syndrome (aHUS) is characterized by the triad of microangiopathic hemolytic anemia, thrombocytopenia, and renal impairment. Neonatal cases are extremely uncommon. Plasma therapy is the first choice therapy in patients with aHUS based on the belief of an underlying complement dysregulation. Alternatively, eculizumab, which targets complement 5, is used to block complement activation. CASE-DIAGNOSIS/TREATMENT: Sudden onset macroscopic hematuria, hypertension, and bruises over the entire body were noted in a 5 day-old newborn. Investigations revealed hemolytic anemia, thrombocytopenia, renal impairment, and a low serum C3, leading to the diagnosis of aHUS. Fresh frozen plasma (FFP) infusions and peritoneal dialysis for acute kidney injury were initiated. This approach yielded full renal and hematological remission. The patient was discharged with FFP infusions, but subsequently developed three life-threatening disease recurrences at 1, 3, and 6 months of age. The last relapse presented with uncontrolled hypertension and impaired renal function while the patient was receiving FFP infusions. After the first dose of eculizumab, his renal and hematological parameters returned to normal and his blood pressure normalized. Genetic screening of the CFH gene revealed a novel homozygous p. Tyr1177Cys mutation. CONCLUSION: Eculizumab can be considered as an alternative to plasma therapy in the treatment of specific patients with aHUS, even in infants. Hemolyitic uremic syndrome (HUS), characterized by triad of acute kidney injury, thrombocytopenia, and hemolytic anemia, has considerable morbidity and mortality and is known to be associated with diarrheal illness. It usually occurs after a diarrheal illness due to Shiga-toxin-producing Escherichia coli. Streptococcus pneumoniae is a rare but well recognized trigger for non-diarrhea associated HUS in children, but has not been reported in adults. We report a case of an adult presenting with pneumococcal pneumonia complicated by HUS and required renal replacement therapy. Hemolytic uremic syndrome (HUS) is a triad of microangiopathic hemolytic anemia, thrombocytopenia, and acute renal failure. The atypical form of HUS is a disease characterized by complement overactivation. Inherited defects in complement genes and acquired autoantibodies against complement regulatory proteins have been described. Incomplete penetrance of mutations in all predisposing genes is reported, suggesting that a precipitating event or trigger is required to unmask the complement regulatory deficiency. The underlying genetic defect predicts the prognosis both in native kidneys and after renal transplantation. The successful trials of the complement inhibitor eculizumab in the treatment of atypical HUS will revolutionize disease management. Hemolytic uremic syndrome (HUS) is a rare thrombotic complication characterized by a triad of microangiopathic hemolytic anemia, thrombocytopenia, and acute renal failure. HUS may be caused by several different conditions, including infection, maligcy, and chemotherapeutic agents, such as mitomycin, cisplatin, and most recently, gemcitabine. The outcome of gemcitabine-induced HUS is poor, and the disease has a high mortality rate. This study reports a case of gemcitabine-induced HUS in a patient with pancreatic cancer in Korea. Atypical hemolytic uremic syndrome (aHUS) is rare and comprises the triad of microangiopathic hemolytic anemia, thrombocytopenia, and acute kidney injury. Recently, abnormalities in the mechanisms underlying complement regulation have been focused upon as causes of aHUS. The prognosis for patients who present with aHUS is very poor, with the first aHUS attack being associated with a mortality rate of approximately 25%, and with approximately 50% of cases resulting in end-stage renal disease requiring dialysis. If treatment is delayed, there is a high risk of this syndrome progressing to renal failure. Therefore, we have developed diagnostic criteria for aHUS to enable its early diagnosis and to facilitate the timely initiation of appropriate treatment. We hope these diagnostic criteria will be disseminated to as many clinicians as possible and that they will be used widely. Atypical hemolytic uremic syndrome (aHUS) is a relatively rare disorder described by the triad of hemolytic anemia, thrombocytopenia, and renal failure. Atypical HUS could be genetic, acquired, or idiopathic (without known genetic changes or environmental triggers). Monoclonal protein has uncommonly been reported as a cause of microangiopathic hemolytic anemia (MAHA). We report a 59-year-old white man who presented with acute kidney injury (AKI) with MAHA and was given a diagnosis of aHUS with monoclonal gammopathy. His kidney function and proteinuria worsened with persistent hemolysis despite eculizumab and later cyclophosphamide and prednisone treatment. He responded well to VRD (bortezomib, lenalidomide, and dexamethasone) regimen. Renal function, proteinuria, and hemolysis all improved, and he was been in remission for more than 15 months. To our knowledge, this is the first report of successful treatment with bortezomib-based regimen for a patient with aHUS and monoclonal protein refractory to eculizumab therapy. Atypical hemolytic uremic syndrome (aHUS) is a rare disease characterized by the triad of microangiopathic hemolytic anemia, thrombocytopenia, and acute renal failure. The term aHUS was historically used to distinguish this disorder from Shiga-toxin producing Escherichia coli (STEC)-HUS. Many aHUS cases (approximately 70%) are reportedly caused by uncontrolled complement activation due to genetic mutations in the alternative pathway, including complement factor H (CFH), complement factor I (CFI), membrane cofactor protein (MCP), thrombomodulin (THBD), complement component C3 (C3), and complement factor B (CFB). Mutations in the coagulation pathway, such as diacylglycerol kinase ε (DGKE) and plasminogen, are also reported to be causes of aHUS. In this review, we have focused on aHUS due to complement dysfunction. aHUS is suspected based on plasma ADAMTS13 activity of 10% or more, and being negative for STEC-HUS, in addition to the aforementioned triad. Complement genetic studies provide a more specific diagnosis of aHUS. Plasma therapy is the first-line treatment for patients with aHUS and should be initiated as soon as the diagnosis is suspected. Recently, eculizumab, a humanized monoclonal antibody against C5, was shown to be an effective treatment for aHUS. Therefore, early diagnosis and identification of the underlying pathogenic mechanism is important for improving the outcome of aHUS. Hemolytic uremic syndrome (HUS) is a clinical syndrome characterized by the triad of thrombotic microangiopathy, thrombocytopenia, and acute kidney injury. Hemolytic uremic syndrome represents a heterogeneous group of disorders with variable etiologies that result in differences in presentation, management and outcome. In recent years, better understanding of the HUS, especially those due to genetic mutations in the alternative complement pathway have provided an update on the terminology, classification, and treatment of the disease. This review will provide the updated classification of the disease and the current diagnostic and therapeutic approaches on the complement-mediated HUS in addition to STEC-HUS which is the most common cause of the HUS in childhood.
Does physical activity influence gut hormones?
Yes.
Syrian golden hamsters when allowed free access to food and an exercise wheel will run long distances and develop hyperphagia and accelerated linear body growth with high circulating levels of growth hormone and insulin. Somatostatin, a widely distributed brain-gut neurohormonal peptide, modulates nutrient absorption and may regulate food intake. To examine the role of circulating plasma somatostatin-like immunoreactivity (SRIF-LI; pg/ml) in exercise induced hyperphagia 4 groups of animals were studied; an unrestricted exercise group (279.0 +/- 107.7, n = 10); a sedentary group (121.1 +/- 40.8, n = 8); a restricted exercise group (107.7 +/- 12.4, n = 6); and a restricted no exercise group (115.5 +/- 45.9, n = 9). Thus, the unrestricted exercise group has a significantly elevated SRIF-LI concentration (P less than 0.01) while there was no difference between the other 3 groups. The elevation of plasma SRIF-LI in the unrestricted exercise group may represent a response to modulate increased nutrient entry in this group or may represent an incompletely effective satiety signal. Leptin, an ob gene product of adipocytes, plays a key role in the control of food intake and energy expenditure but little is known about leptin response to strenuous exercise in fasted and fed subjects or before and after blood donation. This study was designed to determine the immediate effects of strenuous exercise in healthy volunteers under fasting or fed conditions and before and one day after blood donation (450 ml) on plasma levels of leptin and gut hormones [gastrin, cholecystokinin (CCK), pancreatic polypeptide (PP) and insulin], as well as on "stress" hormones (cortisol, catecholamines and growth hormone. Two groups (A and B) of healthy non-smoking male volunteers were studied. All subjects performed incremental exercise tests until exhaustion (up to maximal oxygen uptake--VO2max), followed by 2 h of rest session. Group A perfomed the tests on a treadmill, while group B on a cycloergometer. In group A, one exercise was performed under fasting conditions and the second following ingestion of a standard liquid meal. In group B, one exercise test was performed as a control test and the second 24 h after blood donation (450 ml). Blood samples were withdrawn 5 min before the start of the test, at the VO2max, and 2 h after finishing the exercise. No significant change in plasma teptin were observed both immediately and 2 h after the exercise in fasted subjects, but after the meal the plasma leptin at VO2max and 2 h after the test was significantly higher, while after blood donation was significantly reduced. The postprandial rise in plasma leptin was accompanied by a marked increment in gut hormones; gastrin, CCK and PP and stress hormones such as norepinephrine, cortisol and GH. These hormonal changes could contribute to the postprandial rise in plasma leptin concentrations, while the fall of leptin after blood donation could be attributed to the inadequate response of stress hormones and autonomic nervous system to exhausting exercise. We conclude that strenuous physical exercise; 1) fails to affect plasma leptin level but when performed after meal but not after blood withdrawal it results in an increase and fall in plasma leptin, and 2) the release of gut hormones (gastrin, CCK and PP) and stress hormones (norepinephrine, cortisol, GH) increase immediately after exercise independently of feeding or blood donation and 3) following blood donation the strenuous exercise resulted in a marked reduction in the plasma leptin, cortisol and GH concentrations, possibly due to the impairment in the autonomic nervous control of these hormones. BACKGROUND: Although hormonal responses to exercise performed in fed state are well documented, far less in known about the effect of a single exercise bout, performed after overnight fasting, on cardio-respiratory responses and hormones secretion. It has been reported that recently discovered hormones as leptin and ghrelin may affect cardiovascular responses at rest. However, their effect on the cardiovascular responses to exercise is unknown. AIMS: This study was designed to determine the effect of overnight fasting on cardio- respiratory responses during moderate incremental exercise. We have hypothesised that fasting / exercise induced changes in plasma leptin / ghrelin concentrations may influence cardiovascular response. MATERIAL AND METHODS: Eight healthy non-smoking men (means +/- SE.: age 23.0 +/- 0.5 years; body mass 71.9 +/- 1.5 kg; height 179.1 +/- 0.8 cm; BMI 22.42 +/- 0.49 kg x m(-2) with VO2max of 3.71 +/- 0.10 l x min(-1)) volunteered for this study. The subjects performed twice an incremental exercise test, with the increase of power output by 30 W every 3 minutes. Tests were performed in a random order: once in the feed state--cycling until exhaustion and second, about one week later, after overnight fasting--cycling until reaching 150 W. RESULTS: In the present study we have compared the results obtained during incremental exercise performed only up to 150 W (59 +/- 2 % of VO2max) both in fed and fasted state. Heart rate measured during exercise at each power output, performed in fasted state was by about 10 bt x min(-1) (p = 0.02) lower then in fed subjects. Respiratory quotient and plasma lactate concentration in fasted state were also significantly (p<0.001) lower than in the fed state. Pre-exercise plasma leptin and ghrelin concentrations were not significantly different in fed and fasted state. Exercise induced increase in hGH was not accompanied by a significant changes in the studied gut hormones such as ghrelin, leptin, and insulin, except for plasma gastrin concentration, which was significantly (p = 0.008) lower in fasting subjects at the power output of 150 W. Plasma [IL-6] at rest before exercise performed in fasted state was significantly (p = 0.03) elevated in relation to the fed state. This was accompanied by significantly higher (p = 0.047) plasma noradrenaline concentration. Plasma IL-6 concentration at rest in fed subjects was negatively correlated with plasma ghrelin concentration (r = -0.73, p < 0.05) and positively correlated with plasma insulin concentration (r = 0.78, p < 0.05). Significant negative correlation (r = -0.90; p < 0.05) was found between plasma insulin and ghrelin concentration at rest in fed subjects. CONCLUSIONS: We have concluded that plasma leptin and ghrelin concentrations have no significant effect on the fasting-induced attenuation of heart rate during exercise. We have postulated that this effect is caused by increased plasma norepinephrine concentration, leading to the increase in systemic vascular resistance and baroreceptor mediated vagal stimulation. Moreover we believe, that the fasting-induced significant increase in plasma IL-6 concentration at rest, accompanied by higher plasma norepinephrine concentration and lower RQ, belongs to the physiological responses, maintaining energy homeostasis in the fasting state. BACKGROUND: Serum leptin variation is commonly associated with fat percentage (%), body mass index (BMI), and activity. In this investigation, we report population differences in mean leptin levels in healthy men as well as associations with fat % and BMI that are independent of these factors and reflect likely variation resulting from chronic environmental conditions. METHODS: Serum leptin levels, fat %, and BMI were compared between lean American distance runners and healthy Ache Native Americans of Paraguay. Mean levels were compared as were the regressions between fat %, BMI, and leptin. Comparisons were performed between male American distance runners (n = 13, mean age 32.2 +/- 9.2 SD) and highly active male New World indigenous population (Ache of Paraguay, n = 20, mean age 32.8 +/- 9.2) in order to determine whether significant population variation in leptin is evident in physically active populations living under different ecological circumstances independent of adiposity and BMI. RESULTS: While the Ache were hypothesized to exhibit higher leptin due to significantly greater adiposity (fat %, Ache 17.9 +/- 1.8 SD; runners 9.7 +/- 3.2, p < 0.0001), leptin levels were nonetheless significantly higher in American runners (Ache 1.13 ng/ml +/- 0.38 SD; runners 2.19 +/- 1.15; p < 0.007). Significant differences in the association between leptin and fat % was also evident between Ache and runner men. Although fat % was significantly related with leptin in runners (r = 0.90, p < 0.0001) fat % was negatively related in Ache men (r = -0.50, p < 0.03). CONCLUSION: These results illustrate that chronic ecological conditions in addition to activity are likely factors that contribute to population variation in leptin levels and physiology. Population variation independent of adiposity should be considered to be an important source of variation, especially in light of ethnic and population differences in the incidence and etiology of obesity, diabetes, and other metabolic conditions. This study investigated the acute effects of exercise on the postprandial levels of appetite-related hormones and metabolites, energy intake (EI) and subjective measures of appetite. Ghrelin, polypeptide YY (PYY), glucagon-like peptide-1 (GLP-1) and pancreatic polypeptide (PP) were measured in the fasting state and postprandially in 12 healthy, normal-weight volunteers (six males and six females) using a randomised crossover design. One hour after a standardised breakfast, subjects either cycled for 60 min at 65% of their maximal heart rate or rested. Subjective appetite was assessed throughout the study using visual analogue scales and subsequent EI at a buffet meal was measured at the end (3-h post-breakfast and 1-h post-exercise). Exercise significantly increased mean PYY, GLP-1 and PP levels, and this effect was maintained during the post-exercise period for GLP-1 and PP. No significant effect of exercise was observed on postprandial levels of ghrelin. During the exercise period, hunger scores were significantly decreased; however, this effect disappeared in the post-exercise period. Exercise significantly increased subsequent absolute EI, but produced a significant decrease in relative EI after accounting for the energy expended during exercise. Hunger scores and PYY, GLP-1 and PP levels showed an inverse temporal pattern during the 1-h exercise/control intervention. In conclusion, acute exercise, of moderate intensity, temporarily decreased hunger sensations and was able to produce a short-term negative energy balance. This impact on appetite and subsequent energy homeostasis was not explained by changes in postprandial levels of ghrelin; however, 'exercise-induced anorexia' may potentially be linked to increased PYY, GLP-1 and PP levels. We examined whether changes in gut hormone levels due to a single bout of aerobic exercise differ between obese young males and normal controls, and attempted to determine the involvement of hormonal changes during exercise in the regulation of energy balance (EB) in these obese subjects. Seven obese and seven age-matched subjects of normal weight participated in exercise and rest sessions. Subjects consumed a standardized breakfast that was followed by constant cycling exercise at 50% VO(2max) or rest for 60 min. At lunch, a test meal was presented, and energy intake (EI) and relative energy intake (REI) were calculated. Blood samples were obtained at 30 min intervals during both sessions for measurement of glucose, insulin, glucagon, ghrelin, peptide YY (PYY), and glucagon-like peptide-1 (GLP-1). Plasma levels of PYY and GLP-1 were increased by exercise, whereas plasma ghrelin levels were unaffected by exercise. The areas under the curve (AUC) of the time courses of PYY and GLP-1 levels did not significantly differ between the two groups. In contrast, EI and REI were decreased by exercise in both groups, and energy deficit was significantly larger in obese subjects than in normal controls. The present findings suggest that short-term EB during a single exercise session might be regulated not by increased amounts of these gut hormones per se. There is growing interest in the effects of exercise on plasma gut hormone levels and subsequent energy intake (EI) but the effects of mode and exercise intensity on anorectic hormone profiles on subsequent EI remain to be elucidated. We aimed to investigate whether circulating peptide YY(3-36) (PYY(3-36)) and glucagon-like peptide-1 (GLP-1 or GCG as listed in the HUGO Database) levels depend on exercise intensity, which could affect subsequent EI. Ten young male subjects (mean+/-s.d., age: 23.4+/-4.3 years, body mass index: 22.5+/-1.0 kg/m(2), and maximum oxygen uptake (VO(2 max)): 45.9+/-8.5 ml/kg per min) received a standardized breakfast, which was followed by constant cycling exercise at 75% VO(2 max) (high intensity session), 50% VO(2 max) (moderate intensity session), or rest (resting session) for 30 min. At lunch, a test meal was presented, and EI was calculated. Blood samples were obtained during three sessions for measurements of glucose, insulin, PYY(3-36), and GLP-1, which includes GLP-1 (7-36) amide and GLP-1 (9-36) amide. Increases in blood PYY(3-36) levels were dependent on the exercise intensity (effect of session: P<0.001 by two-way ANOVA), whereas those in GLP-1 levels were similar between two different exercise sessions. Of note, increase in area under the curve values for GLP-1 levels was negatively correlated with decrease in the EI in each exercise session (high: P<0.001, moderate: P=0.002). The present findings raise the possibility that each gut hormone exhibits its specific blood kinetics in response to two different intensities of exercise stimuli and might play differential roles in regulation of EI after exercise. BACKGROUND: Short-term physical inactivity affects energy balance and is considered conducive to weigh gain. Long-term effects are unknown. OBJECTIVE: The objective of the study was to use a bed-rest model to determine the long-term effects of physical inactivity on energy balance regulation and test the effect of exercise training on energy balance adjustment to physical inactivity. DESIGN: Sixteen lean women were divided into two groups (n = 8 each): a control group subjected to a strict 60-d bed rest and an exercise group subjected to a combined aerobic/resistive exercise training concomitantly to bed rest. Body composition, spontaneous energy intake, hunger, total energy expenditure (TEE), and fasting gut hormones were measured. RESULTS: Based on bed-rest-induced body composition changes, the control group were in slight negative energy balance (-0.4 +/- 0.4 MJ/d; P = 0.01 vs. zero), essentially due to muscle atrophy (P < 0.001 vs. zero). The stable fat mass (P = 0.19 vs. zero), and the matching between spontaneous energy intake and TEE indicated, however, a stable energy balance. Hunger and gut hormones remained unchanged during the bed rest. In the exercise group, TEE was 24% higher than in the control group (P = 0.004). Unexpectedly, desire to consume food (P = 0.025) decreased and spontaneous energy intake (P = NS) was not stimulated, promoting a negative energy balance (-1.1 +/- 0.5 MJ/d, P = 0.0003 vs. zero). CONCLUSIONS: Energy balance is regulated during 2 months of physical inactivity, contrasting with short-term experiments. Conversely, exercise-induced energy expenditure in bed-resting subjects who have no spontaneous physical activity did not induce hunger and promoted a negative energy balance, suggesting a potential role of nonexercise physical activities in energy balance regulation. Recent studies suggest that spontaneous physical activity (SPA) may be under the non-conscious control of neuroendocrine circuits that are known to control food intake. To further elucidate endocrine gut-brain communication as a component of such circuitry, we here analyzed long-term and acute effects of the gastrointestinal hormones ghrelin and PYY 3-36 as well as their hypothalamic neuropeptide targets NPY, AgRP and POMC (alpha-MSH), on locomotor activity and home cage behaviors in rats. For the analysis of SPA, we used an automated infrared beam break activity measuring system, combined with a novel automated video-based behavior analysis system (HomeCageScan (HCS)). Chronic (one-month) peripheral infusion of ghrelin potently increased body weight and fat mass in rats. Such positive energy balance was intriguingly not due to an overall increased caloric ingestion, but was predomitly associated with a decrease in SPA. Chronic intracerebroventricular infusion (7 days) of ghrelin corroborated the decrease in SPA and suggested a centrally mediated mechanism. Central administration of AgRP and NPY increased food intake as expected. AgRP administration led to a delayed decrease in SPA, while NPY acutely (but transiently) increased SPA. Behavioral dissection using HCS corroborated the observed acute and transient increases of food intake and SPA by central NPY infusion. Acute central administration of alpha-MSH rapidly decreased food intake but did not change SPA. Central administration of the NPY receptor agonist PYY 3-36 transiently increased SPA. Our data suggest that the control of spontaneous physical activity by gut hormones or their neuropeptide targets may represent an important mechanistic component of energy balance regulation. Ghrelin and peptide YY (PYY) are newly recognized gut peptides involved in appetite regulation. Plasma ghrelin concentrations are elevated in fasting and suppressed following a meal, while PYY concentrations are suppressed in fasting and elevated postprandially. We determine whether ghrelin and PYY are altered by a low-fat, high-carbohydrate (10% fat, 75% carbohydrate) or moderate-fat, moderate-carbohydrate (35% fat, 50% carbohydrate) diet and; whether these peptides are affected by intense endurance running (which is likely to temporarily suppress appetite). Twenty-one endurance-trained runners followed a controlled diet (25% fat) and training regimen for 3 days before consuming the low-fat or isoenergetic moderate-fat diet for another 3 days in random cross-over fashion. On day 7 runners underwent glycogen restoration and then completed a 90-minute pre-loaded 10-km time trial on day 8, following a control breakfast. Blood samples were obtained on days 4 and 7 (fasting), and day 8 (non-fasting) before and after exercise for analysis of ghrelin, PYY, insulin and growth hormone (GH). Insulin, GH, Ghrelin and PYY changed significantly over time (p < 0.0001) but were not influenced by diet. Ghrelin was elevated during fasting (days 4 and 7), while insulin and PYY were suppressed. Following the pre-exercise meal, ghrelin was suppressed ~17% and insulin and PYY were elevated ~157 and ~40%, respectively, relative to fasting (day 7). Following exercise, PYY, ghrelin, and GH were significantly (p < 0.0001) increased by ~11, ~16 and ~813%, respectively. The noted disruption in the typical inverse relationship between ghrelin and PYY following exercise suggests that interaction of these peptides may be at least partially responsible for post-exercise appetite suppression. These peptides do not appear to be influenced by dietary fat intake. Nine female runners and ten walkers completed a 60 min moderate-intensity (70% VO(2)max) run or walk, or 60 min rest in counterbalanced order. Plasma concentrations of the orexogenic peptide ghrelin, anorexogenic peptides peptide YY (PYY), glucagon-like peptide-1 (GLP-1), and appetite ratings were measured at 30 min interval for 120 min, followed by a free-choice meal. Both orexogenic and anorexogenic peptides were elevated after running, but no changes were observed after walking. Relative energy intake (adjusted for cost of exercise/rest) was negative in the meal following running (-194 ± 206 kcal) versus walking (41 ± 196 kcal) (P = 0.015), although both were suppressed (P < 0.05) compared to rest (299 ± 308 and 284 ± 121 kcal, resp.). The average rate of change in PYY and GLP-1 over time predicted appetite in runners, but only the change in GLP-1 predicted hunger (P = 0.05) in walkers. Results provide evidence that exercise-induced alterations in appetite are likely driven by complex changes in appetite-regulating hormones rather than change in a single gut peptide. Sprint interval exercise improves several health markers but the appetite and energy balance response is unknown. This study compared the effects of sprint interval and endurance exercise on appetite, energy intake and gut hormone responses. Twelve healthy males [mean (SD): age 23 (3) years, body mass index 24.2 (2.9) kg m(-2), maximum oxygen uptake 46.3 (10.2) mL kg(-1) min(-1)] completed three 8 h trials [control (CON), endurance exercise (END), sprint interval exercise (SIE)] separated by 1 week. Trials commenced upon completion of a standardised breakfast. Sixty minutes of cycling at 68.1 (4.3) % of maximum oxygen uptake was performed from 1.75-2.75 h in END. Six 30-s Wingate tests were performed from 2.25-2.75 h in SIE. Appetite ratings, acylated ghrelin and peptide YY (PYY) concentrations were measured throughout each trial. Food intake was monitored from buffet meals at 3.5 and 7 h and an overnight food bag. Appetite (P < 0.0005) and acylated ghrelin (P < 0.002) were suppressed during exercise but more so during SIE. Peptide YY increased during exercise but most consistently during END (P < 0.05). Acylated ghrelin was lowest in the afternoon of SIE (P = 0.018) despite elevated appetite (P = 0.052). Exercise energy expenditure was higher in END than that in SIE (P < 0.0005). Energy intake was not different between trials (P > 0.05). Therefore, relative energy intake (energy intake minus the net energy expenditure of exercise) was lower in END than that in CON (15.7 %; P = 0.006) and SIE (11.5 %; P = 0.082). An acute bout of endurance exercise resulted in lower appetite perceptions in the hours after exercise than sprint interval exercise and induced a greater 24 h energy deficit due to higher energy expenditure during exercise. The present study determined the changes in appetite and appetite-regulating gut hormones during and following bouts of both rope skipping exercise (weight-bearing) and bicycle ergometer exercise (non-weight-bearing). After a 12-h fast, 15 young men (mean ± SD, age 24.4 ± 1.7 yrs, maximal oxygen uptake 47.0 ± 6.5 mL/kg/min) participated in three 160 min trials: (1) rope skipping exercise (295 ± 40 kcal, 3 sets × 10 min with 5-min interval, then rested for 120 min); (2) bicycle ergometer exercise (288 ± 36 kcal, 3 sets × 10 min with 5-min interval, then rested for 120 min); (3) control (rested for 160 min). Ratings of perceived hunger and acylated ghrelin were suppressed and total peptide YY (PYY) were increased during and immediately after exercise in both exercise trials, but glucagon liked peptide-1 was not changed. Furthermore, suppressed hunger during rope skipping exercise was greater than that during bicycle ergometer exercise, but there were no differences in acylated ghrelin and total PYY. These results indicate that weight-bearing exercise has a greater exercise-induced appetite suppressive effect compared with non-weight-bearing exercise, and both forms of exercise lowered acylated ghrelin and increased total PYY, but the changes did not differ significantly between exercise modes.
What are the effects of depleting protein km23-1 (DYNLRB1) in a cell?
The knockdown of km23-1 results in numerous effects at the cellular level, such as decreased cell migration. Additionaly, km23-1 is involved in signalling pathways and its knockdown results in decreased RhoA activation, inhibition of TGFβ-mediated activation of ERK and JNK, phosphorylation of c-Jun, transactivation of the c-Jun promoter and decreased TGFbeta responses.
We previously identified km23 as a novel TGFbeta receptor-interacting protein. Here we show that km23 is ubiquitously expressed in human tissues and that cell-type specific differences in endogenous km23 protein expression exist. In addition, we demonstrate that the phosphorylation of km23 is TGFbeta-dependent, in that EGF was unable to phosphorylate km23. Further, the kinase activity of both TGFbeta receptors appears to play a role in the TGFbeta-mediated phosphorylation of km23, although TGFbeta RII kinase activity is absolutely required for km23 phosphorylation. Blockade of km23 using small interfering RNAs significantly decreased key TGFbeta responses, including induction of fibronectin expression and inhibition of cell growth. Thus, our results demonstrate that km23 is required for TGFbeta induction of fibronectin expression and is necessary, but not sufficient, for TGFbeta-mediated growth inhibition. PURPOSE: A very high frequency of somatic mutations in the transforming growth factor-beta signaling component km23 has been reported in a small series of ovarian cancers (8 of 19, 42%). Functional studies showed that some mutations disrupt km23 function, resulting in aberrant transforming growth factor-beta signaling and presumably enhanced tumorigenicity. If verified, this would elevate mutation of km23 as the single most frequent somatic event in ovarian cancer. EXPERIMENTAL DESIGN: We sought to verify the frequency of silencing of km23 among 104 primary ovarian cancers (49 serous, 18 mucinous, 29 endometrioid/clear cell, and 8 undifferentiated) as well as 72 breast and 61 colorectal cancers by undertaking both somatic mutation and promoter methylation analyses. All four exons of km23 were individually amplified from genomic DNA with primers complementary to surrounding intronic sequences and analyzed by single-stranded conformational polymorphism analysis. RESULTS: Two germ line polymorphisms were identified, but none of the 237 tumors analyzed harbored somatic km23 mutations. In addition, promoter methylation analysis showed that in all cases, the 5' CpG island was unmethylated. CONCLUSIONS: Our data suggest that silencing of km23, either through somatic genetic mutation or promoter hypermethylation, is rare in ovarian, breast, and colorectal cancers. The reduced folate carrier (RFC) is a major folate transport system in mammalian cells. RFC is highly expressed in the intestine and believed to play a role in folate absorption. Studies from our laboratory and others have characterized different aspects of the intestinal folate absorption process, but little is known about possible existence of accessory protein(s) that interacts with RFC and influences its physiology and/or cell biology. We investigated this issue by employing a bacterial two-hybrid system to screen a BacterioMatch II human intestinal cDNA library using the large intracellular loop between transmembrane domains 6 and 7 of the human RFC (hRFC) as bait. Our screening has resulted in the identification of dynein light chain road block-1 (DYNLRB1) as an interacting partner with hRFC. Existence of a direct protein-protein interaction between hRFC and DYNLRB1 was confirmed by in vitro pull-down assay and in vivo mammalian two-hybrid luciferase assay and coimmunoprecipitation analysis. Furthermore, confocal imaging of live human intestinal epithelial HuTu-80 cells demonstrated colocalization of DYNLRB1 with hRFC. Coexpression of DYNLRB1 with hRFC led to a significant (P < 0.05) increase in folate uptake. On the other hand, inhibiting the endogenous DYNLRB1 with gene-specific small interfering RNA or pharmacologically with a specific inhibitor (vanadate) led to a significant (P < 0.05) decrease in folate uptake. This study demonstrates for the first time the identification of DYNLRB1 as an interacting protein partner with hRFC. Furthermore, DYNLRB1 appears to influence the function and cell biology of hRFC. We have previously reported that the dynein light chain (DLC) km23-1 is required for Smad2-dependent TGFbeta signaling. Here we describe another member of the km23/DYNLRB/LC7/robl family of DLCs, termed km23-2, which is also involved in TGFbeta signaling. We show not only that TGFbeta stimulates the interaction of km23-2 (DYNLRB2) with TGFbeta receptor II (TbetaRII) but also that TGFbeta regulates the interaction between km23-2 and endogenous TbetaRII in vivo. In addition, TGFbeta treatment causes km23-2 phosphorylation, whereas a kinase-deficient form of TbetaRII prevents km23-2 phosphorylation. In contrast to the km23-1 isoform, blockade of km23-2 expression using small interfering RNAs (siRNAs) decreased key TGFbeta/Smad3-specific responses, including the induction of both plasminogen activator inhibitor-1 (PAI-1) gene expression and p21 protein expression. Blockade of km23-1 expression had no effect on these two major TGFbeta/Smad3 responses under similar conditions. Further, km23-2 was required for TGFbeta stimulation of Smad3-dependent Smad-binding element (SBE)2-Luc transcriptional activity, but not for TGFbeta stimulation of Smad2-dependent activin responsive element (ARE)-Lux transcriptional activity. In order to assess the mechanisms underlying the preferential stimulation of Smad3- versus Smad2-specific TGFbeta responses, immunoprecipitation (IP)/blot analyses were performed, which demonstrate that TGFbeta stimulated preferential complex formation of km23-2 with Smad3, relative to Smad2. Collectively, our findings indicate that km23-2 is required for Smad3-dependent TGFbeta signaling. More importantly, we demonstrate that km23-2 has functions in TGFbeta signaling that are distinct from those for km23-1. This is the first report to describe a differential requirement for unique isoforms of a specific DLC family in Smad-specific TGFbeta signaling. km23-1 was originally identified as a TGFß receptor-interacting protein that plays an important role in TGFß signaling. Moreover, km23-1 is actually part of an ancient superfamily of NTPase-regulatory proteins, widely represented in archaea and bacteria. To further elucidate the function of km23-1, we identified novel protein interacting partners for km23-1 by using tandem affinity purification (TAP) and tandem mass spectrometry (MS). Here we show that km23-1 interacted with a class of proteins involved in actin-based cell motility and modulation of the actin cytoskeleton. We further showed that km23-1 modulates the formation of a highly organized stress fiber network. More significantly, we demonstrated that knockdown (KD) of km23-1 decreased RhoA activation in Mv1Lu epithelial cells. Finally, our results demonstrated for the first time that depletion of km23-1 inhibited cell migration of human colon carcinoma cells (HCCCs) in wound-healing assays. Overall, our findings demonstrate that km23-1 regulates RhoA and motility-associated actin modulating proteins, suggesting that km23-1 may represent a novel target for anti-metastatic therapy.
Treatment of which disease was investigated in the MR CLEAN study?
Multicenter Randomized CLinical trial of Endovascular treatment for Acute ischemic stroke in the Netherlands (MR CLEAN) study investigated endovascular treatment for acute ischemic stroke.
In 3 recent randomized controlled trials of intra-arterial treatment of acute ischemic stroke - IMS-III, SYNTHESIS and MR RESCUE - intra-arterial treatment increased the proportion of patients with recanalization and the treatment appeared safe. However, the trials did not show an effect on functional recovery, although a substantial effect could not be excluded. The delay between onset of symptoms and treatment was long, and stent retrievers were used in only a few patients. In our view, a rational and ethical approach would now be to treat quickly with IV rtPA and when possible, refer and include in new randomized clinical trials that compare intra-arterial treatment with standard care, such as MR CLEAN or BASICS in the Netherlands. BACKGROUND: Endovascular or intra-arterial treatment (IAT) increases the likelihood of recanalization in patients with acute ischemic stroke caused by a proximal intracranial arterial occlusion. However, a beneficial effect of IAT on functional recovery in patients with acute ischemic stroke remains unproven. The aim of this study is to assess the effect of IAT on functional outcome in patients with acute ischemic stroke. Additionally, we aim to assess the safety of IAT, and the effect on recanalization of different mechanical treatment modalities. METHODS/DESIGN: A multicenter randomized clinical trial with blinded outcome assessment. The active comparison is IAT versus no IAT. IAT may consist of intra-arterial thrombolysis with alteplase or urokinase, mechanical treatment or both. Mechanical treatment refers to retraction, aspiration, sonolysis, or use of a retrievable stent (stent-retriever). Patients with a relevant intracranial proximal arterial occlusion of the anterior circulation, who can be treated within 6 hours after stroke onset, are eligible. Treatment effect will be estimated with ordinal logistic regression (shift analysis); 500 patients will be included in the trial for a power of 80% to detect a shift leading to a decrease in dependency in 10% of treated patients. The primary outcome is the score on the modified Rankin scale at 90 days. Secondary outcomes are the National Institutes of Health stroke scale score at 24 hours, vessel patency at 24 hours, infarct size on day 5, and the occurrence of major bleeding during the first 5 days. DISCUSSION: If IAT leads to a 10% absolute reduction in poor outcome after stroke, careful implementation of the intervention could save approximately 1% of all new stroke cases from death or disability annually. TRIAL REGISTRATION: NTR1804 (7 May 2009)/ISRCTN10888758 (24 July 2012). INTRODUCTION: A recent randomized controlled trial (RCT), the Multicenter Randomized CLinical trial of Endovascular treatment for Acute ischemic stroke in the Netherlands (MR CLEAN), demonstrated better outcomes with endovascular treatment compared with medical therapy for acute ischemic stroke (AIS). However, previous trials have provided mixed results regarding the efficacy of endovascular treatment for AIS. A meta-analysis of all available trial data was performed to summarize the available evidence. METHODS: A literature search was performed to identify all prospective RCTs comparing endovascular therapies with medical management for AIS. Two datasets were created: (1) all patients randomized after confirmation of large vessel occlusion (LVO) (consistent with the contemporary standard of practice at the majority of centers); and (2) all patients with outcome data who underwent randomization regardless of qualifying vascular imaging. The pre-specified primary outcome measure was modified Rankin Scale score of 0-2 at 90 days. A fixed-effect model was used to determine significance. RESULTS: Five prospective RCTs comparing endovascular therapies with medical management were included in dataset 1 (1183 patients) and six were included in dataset 2 (1903 total patients). Endovascular therapies were associated with significantly improved outcomes compared with medical management (OR 1.67, 95% CI 1.29 to 1.16, p=0.0001) for patients with LVO (dataset 1). This benefit persisted when patients from all six RCTs were included, even in the absence of confirmation of LVO (OR 1.27, 95% CI 1.05 to 1.54, p=0.019; dataset 2). CONCLUSIONS: A meta-analysis of prospective RCTs comparing endovascular therapies with medical management demonstrates superior outcomes in patients randomized to endovascular therapy. BACKGROUND: In patients with acute ischemic stroke caused by a proximal intracranial arterial occlusion, intraarterial treatment is highly effective for emergency revascularization. However, proof of a beneficial effect on functional outcome is lacking. METHODS: We randomly assigned eligible patients to either intraarterial treatment plus usual care or usual care alone. Eligible patients had a proximal arterial occlusion in the anterior cerebral circulation that was confirmed on vessel imaging and that could be treated intraarterially within 6 hours after symptom onset. The primary outcome was the modified Rankin scale score at 90 days; this categorical scale measures functional outcome, with scores ranging from 0 (no symptoms) to 6 (death). The treatment effect was estimated with ordinal logistic regression as a common odds ratio, adjusted for prespecified prognostic factors. The adjusted common odds ratio measured the likelihood that intraarterial treatment would lead to lower modified Rankin scores, as compared with usual care alone (shift analysis). RESULTS: We enrolled 500 patients at 16 medical centers in The Netherlands (233 assigned to intraarterial treatment and 267 to usual care alone). The mean age was 65 years (range, 23 to 96), and 445 patients (89.0%) were treated with intravenous alteplase before randomization. Retrievable stents were used in 190 of the 233 patients (81.5%) assigned to intraarterial treatment. The adjusted common odds ratio was 1.67 (95% confidence interval [CI], 1.21 to 2.30). There was an absolute difference of 13.5 percentage points (95% CI, 5.9 to 21.2) in the rate of functional independence (modified Rankin score, 0 to 2) in favor of the intervention (32.6% vs. 19.1%). There were no significant differences in mortality or the occurrence of symptomatic intracerebral hemorrhage. CONCLUSIONS: In patients with acute ischemic stroke caused by a proximal intracranial occlusion of the anterior circulation, intraarterial treatment administered within 6 hours after stroke onset was effective and safe. (Funded by the Dutch Heart Foundation and others; MR CLEAN Netherlands Trial Registry number, NTR1804, and Current Controlled Trials number, ISRCTN10888758.).
Which factors activate zygotic gene expression during the maternal-to-zygotic transition in zebrafish?
Nanog, Pou5f1 and SoxB1 activate zygotic gene expression during the maternal-to-zygotic transition. Maternal Nanog, Pou5f1 and SoxB1 are required to initiate the zygotic developmental program and induce clearance of the maternal program by activating miR-430 expression.
After fertilization, maternal factors direct development and trigger zygotic genome activation (ZGA) at the maternal-to-zygotic transition (MZT). In zebrafish, ZGA is required for gastrulation and clearance of maternal messenger RNAs, which is in part regulated by the conserved microRNA miR-430. However, the factors that activate the zygotic program in vertebrates are unknown. Here we show that Nanog, Pou5f1 (also called Oct4) and SoxB1 regulate zygotic gene activation in zebrafish. We identified several hundred genes directly activated by maternal factors, constituting the first wave of zygotic transcription. Ribosome profiling revealed that og, sox19b and pou5f1 are the most highly translated transcription factors pre-MZT. Combined loss of these factors resulted in developmental arrest before gastrulation and a failure to activate >75% of zygotic genes, including miR-430. Our results demonstrate that maternal Nanog, Pou5f1 and SoxB1 are required to initiate the zygotic developmental program and induce clearance of the maternal program by activating miR-430 expression.
Is irritable bowel syndrome more common in women with endometriosis?
Yes, irritable bowel syndrome (IBS) is more common in women with endometriosis. It has been shown that 15% of the patients with endometriosis also had IBS. Women with endometriosis are more likely to have received a diagnosis of IBS. Endometriosis may coexist with or be misdiagnosed as IBS.
Both irritable bowel syndrome and endometriosis are common conditions, although symptomatic gastrointestinal endometriosis is extremely rare. We report the case of a patient initially thought to have irritable bowel syndrome, in whom the diagnosis of endometriosis only became clear following a laparotomy for small bowel obstruction. This case highlights the need to question the diagnosis in patients with irritable bowel syndrome when there is any uncertainty, and also to appreciate that other pathology can arise, even when the diagnosis is secure. Chronic symptoms of abdominal pain and irregular bowel habits in women evoke a broad differential diagnosis including irritable bowel syndrome, infection, malabsorption, and inflammatory bowel disease. Endometriosis, a common disorder in young women that can involve the intestinal tract, deserves consideration as well. Intestinal endometriosis is typically asymptomatic; however, when symptoms occur, they can mimic those of irritable bowel syndrome. Identifying intestinal endometriosis can be challenging, but historical points and key clinical features aid in diagnosis. OBJECTIVE: Authors report their experience about a case of intestinal endometriosis that lead cyclic and recurrent rectal bleeding in a fertile-age woman. DESIGN: Report of 1 case with multidisciplinary approach and surgical treatment. Surgical effectiveness evaluation and 2 years follow-up. Brief review on the recent literature and the diagnostic and therapeutic implications. SETTING: Section of General and Thoracic Surgery, Department of General Surgery, Emergency and Organ Transplantation, Policlinico "Paolo Giaccone", Palermo. INTERVENTION: After correct and sure diagnosis, the patient was submitted to sigmoid segmental resection with radical and curative intention. RESULTS: Complete recovery. Follow-up (24 months) negative. CONCLUSIONS: Diagnosis of endometriosis should be considered in women with recurrent monthly abdominal pain and bowel symptoms, especially if accompanied by gynaecologic complaints, even because the significant symptoms overlap with the irritable bowel syndrome (IBS) and makes the differentiation extremely difficult. Treatment of GI endometriosis is best approached in collaboration between gynaecologist experienced and intestinal surgeon. The high accuracy and low complications suggested that EUS-FNA was effective for the correct histologic diagnosis of intestinal endometriosis. The objective of this short review is to identify the particularities of women with endometriosis, especially those complaining of pain and with the most severe lesions. Genetic aberrations play, with a high probability, a major role in the development of this disease, its severity, its tendency to recur and also in its capacity to degenerate. The abnormalities of the endometrium, with exacerbated biological activities, are an example. The woman with endometriosis seems more sensitive to pain through various mechanisms, such as central hypersensitivity and decrease threshold to somatoceptive pain and several associated psychological disorders. Endometriosis is often associated with other painful conditions such as irritable bowel syndrome, interstitial cystitis and fibromyalgia. Finally, also appears also to have a higher risk to develop non Hodgkin's lymphoma or ovarian cancer. These particularities, some of them being still speculative or controversial, should be known in routine practise, in order to offer a better multidisciplinary management, not only for short term, but also long term issues. Endometriosis is defined as the presence of endometrial tissue outside the uterus. The bowel is not often affected. There are no specific clinical findings for intestinal endometriosis. It is typically asymptomatic, but sometimes can present with abdominal pain, diarrhoea, constipation or intestinal obstruction. Ileal perforation is a rare complication of intestinal endometriosis and only a few cases have been reported in the literature. Intestinal endometriosis can mimic many gastrointestinal diseases, such as irritable bowel syndrome, inflammatory bowel disease, infections and neoplasms. The diagnosis is made by laparoscopy or laparotomy. We present a case of a woman with intermittent abdominal pain and ileal perforation secondary to intestinal endometriosis. OBJECTIVE: To examine the headache characteristics of women with migraine and endometriosis (EM), and differences in the prevalence of comorbid conditions between female migraineurs with EM, without EM and nonheadache controls. BACKGROUND: Migraine and EM are common conditions in women of reproductive age, and both are influenced by ovarian hormones. The comorbidity of migraine and EM is newly recognized, but reasons for the association are uncertain. METHODS: This is a cross-sectional study of female headache outpatients and healthy controls conducted at University of Toledo and Duke University in 2005 and 2006. After a headache specialist determined headache frequency and diagnosis (based on criteria of the second International Classification of Headache Disorders), patients completed a self-administered electronic survey with information on demographics, headache-related disability, menstrual disorders, premenstrual dysphoric disorder (PMDD), vascular event risk, and comorbid conditions, including irritable bowel syndrome (IBS), fibromyalgia (FM), chronic fatigue syndrome (CFS), interstitial cystitis (IC), depression, and anxiety. RESULTS: Study enrolled 171 women with migraine and 104 controls. EM was reported more commonly in migraineurs than in controls (22% vs 9.6%, P < .01). Frequency of chronic headache was higher in migraineurs with EM compared to without EM (P= .002) and median headache-related disability scores were also higher in the EM group (P= .025). Symptoms of PMDD were more common in migraineurs, but frequency did not differ by EM status. Migraineurs with EM reported more menorrhagia, dysmenorrhea, and infertility compared to the migraine cohort without EM and to controls. Depression, anxiety, IBS, FM, CFS, and IC were more common in migraine with EM group than in controls. Anxiety (OR = 2.2, 95% CI 1.0-4.7), IC (OR = 10.6, 95% CI 1.9-56.5), and CFS (OR = 3.6, 95% CI 1.1-11.5) were more common in migraine with EM group, than in the cohort with migraine without EM. CONCLUSION: Prevalence of EM is higher in women with migraine than in nonheadache controls. Migraineurs with EM have more frequent and disabling headaches, and are more likely to have other comorbid conditions affecting mood and pain, compared to migraineurs without EM. Rectovaginal endometriosis is a severe variant of endometriosis. Common presenting symptoms for endometriosis include dysmenorrhoea, pelvic pain and dyspareunia. It is now recognised that there are other less traditional symptoms of endometriosis that are also relatively common. The aim of this study is to assess the relative strength of each of the potential symptoms of rectovaginal endometriosis and compare these with the laparoscopic and histological findings. In this retrospective, observational study the overall prevalence of rectovaginal endometriosis in the group was 31.4%. The presence of dyschesia gave a likelihood ratio of 1.27 (95% CI: 0.56 - 2.89) with a predictive prevalence of rectovaginal endometriosis of 37%. Apareunia and nausea or abdominal bloating were particularly strong markers for rectovaginal disease with a predictive prevalence of 87% and 89%, respectively. The classical symptoms often attributed to irritable bowel syndrome are also common in women with rectovaginal disease. In women, clinical studies suggest that functional pain syndromes such as irritable bowel syndrome, interstitial cystitis, and fibromyalgia, are co-morbid with endometriosis, chronic pelvic pain, and others diseases. One of the possible explanations for this phenomenon is visceral cross-sensitization in which increased nociceptive input from inflamed reproductive system organs sensitize neurons that receive convergent input from an unaffected visceral organ to the same dorsal root ganglion (DRG). The purpose of this study was to determine whether primary sensory neurons that innervate both visceral organs--the uterus and the colon--express nociceptive ATP-sensitive purinergic (P2X3) and capsaicin-sensitive vanilloid (TRPV1) receptors. To test this hypothesis, cell bodies of colonic and uterine DRG were retrogradely labeled with fluorescent tracer dyes micro-injected into the colon/rectum and uterus of rats. Ganglia were harvested, cryo-protected, and cut in 20-microm slices for fluorescent microscopy to identify positively stained cells. Up to 5% neurons were colon-specific or uterus-specific, and 10%-15% of labeled DRG neurons innervate both viscera in the lumbosacral neurons (L1-S3 levels). We found that viscerally labeled DRGs express nociceptive P2X3 and TRPV1 receptors. Our results suggest a novel form of visceral sensory integration in the DRG that may underlie co-morbidity of many functional pain syndromes. BACKGROUND: Endometriosis commonly presents with a range of symptoms none of which are particularly specific for the condition, often resulting in misdiagnosis or delay in diagnosis. AIM: To investigate gastrointestinal symptoms in women with endometriosis and compare their frequency with that of the classical gynaecological symptoms. METHODS: Systematic exploration of symptoms in a consecutive series of 355 women undergoing operative laparoscopy for suspected endometriosis. RESULTS: Endometriosis was confirmed by histology in 290 women (84.5%). Bowel lesions were present in only 7.6%. Ninety per cent of women had gastrointestinal symptoms, of which bloating was the most common (82.8%), but 71.3% also had other bowel symptoms. All gastrointestinal symptoms were similarly predictive of histologically confirmed endometriosis. Seventy-six women (21.4%) had previously been diagnosed with irritable bowel syndrome and 79% of them had endometriosis confirmed. CONCLUSION: Gastrointestinal symptoms are nearly as common as gynaecological symptoms in women with endometriosis and do not necessarily reflect bowel involvement. AIM: The aim of this study was to evaluate how many patients with endometriosis have concomitant irritable bowel syndrome (IBS) and/or constipation according to the Rome III criteria. Furthermore, the value of an additional gastroenterological consultation with therapeutic advice was evaluated. METHOD: Patients with proven endometriosis were included in a prospective, single-centre study. A questionnaire was undertaken regarding IBS and chronic constipation. Patients with symptoms consistent with the Rome III criteria for IBS were referred to our gastroenterological outpatient clinic. RESULTS: In total 101 patients were included. Endometriosis was diagnosed surgically in 97% and visually in the vagina in 3%. Fifteen per cent of the patients with endometriosis also had IBS and 14% of the patients with endometriosis had functional constipation without IBS. Of the 22 patients finally presenting to the gastroenterologist, five had a significant stenotic rectosigmoid lesion and were treated surgically. The remaining 17 patients were treated conservatively. Defecation symptoms improved in 86% and pain was reduced in 64%. CONCLUSION: In patients with endometriosis, 29% also had IBS or constipation. Referral to a gastroenterologist resulted in improvement of defaecation in 86%, and 64% reported a reduction in the degree of pain. BACKGROUND: Advances in understanding the epidemiology of endometriosis have lagged behind other diseases because of methodological problems related to disease definition and control selection. AIM: To identify possible risk factors associated with the development of endometriosis among a sample of Egyptian women. MATERIALS AND METHODS: A case-control study was conducted in the University Maternity Hospital and some private hospitals in Alexandria. The sample included 110 cases recently diagnosed with endometriosis and 220 hospital-based, age-matched controls. RESULTS: Using the logistic regression analysis, nulligravidae were four times more likely to develop endometriosis than gravid women [adjusted odds ratio (AOR)=4.0, 95% confidence interval (CI) (2.2-7.6)]. Short cycles were associated with approximately six times increase in risk of endometriosis [AOR=6.1, 95% CI (2.9-12.8)]. Women with irregular cycles were three times more likely to develop endometriosis than women with regular cycles [AOR=3.5, 95% CI (1.89-6.71)]. Similarly, women with a history of irritable bowel syndrome were twice as likely to develop endometriosis [AOR=1.9, 95% CI (1.03-3.87)]. Women who had one or more relatives with endometriosis were 1.2 times more likely to develop endometriosis [AOR=1.2, 95% CI (1.19-1.43)]. CONCLUSION AND RECOMMENDATIONS: Nulliparous and women reporting short and irregular cycles were at a significantly increased risk of developing endometriosis. A weak association between reported family history of endometriosis and history of irritable bowel syndrome and the development of endometriosis was also observed. Designing and implementing health education programs about endometriosis and its related risk factors should be a priority to ensure early diagnosis of the disease. INTRODUCTION: Intestinal endometriosis is often an infrequently considered diagnosis in female of childbearing age by general surgeon. There is a delay in diagnosis because of constellation of symptoms and lack of specific diagnostic modalities. Patients suffer from intestinal endometriosis for many years before they are diagnosed. Often, such patients are labelled with irritable bowel syndrome. Intestinal endometriosis has a diagnostic time delay of 8-11 years due to its non-specific clinical features and multi-system involvement. PRESENTATION OF CASE: Our patient was a 32 years old Caucasian female who was referred to us with features of intestinal obstruction. Despite repeated clinical assessments and use of different diagnostic modalities the diagnosis was still inconclusive even after 21 days of her first presentation to primary care physician. She had an exploratory laparotomy, sigmoid colectomy, and Hartmann's procedure with a temporary colostomy with us. Histopathology confirmed endometriosis and also showed melanosis coli. She was referred to the gynaecological team for review and follow up. DISCUSSION: Intestinal endometriosis should be considered as a differential diagnosis in female patients of childbearing age group presenting with non-specific gastrointestinal signs and symptoms. Our patient manifested intestinal endometriosis and melanosis coli on histopathology suggesting symptoms of long duration. CONCLUSION: Bowel endometriosis is a less considered and often ignored differential diagnosis in acute and chronic abdomen. This condition has considerable effect on patient's health both physically and psychologically. STUDY OBJECTIVE: Adult women with endometriosis are often diagnosed with comorbid pain, mood, and autoimmune conditions. This study aims to describe the occurrence of pain syndromes, mood conditions, and asthma in adolescents and young women with endometriosis evaluated at our medical center. DESIGN: Retrospective review of medical records. SETTING: Department of Obstetrics and Gynecology at a tertiary referral center. PARTICIPANTS: 138 adolescents/young women who were less than age 24 years at the time of their initial visit at our medical center, and whose surgical diagnosis of endometriosis was made at our institution or by outside institutions by the age of 21. INTERVENTIONS: None. MAIN OUTCOME MEASURES: Prevalence of comorbid pain syndromes (defined as interstitial cystitis, irritable bowel syndrome, chronic headaches, chronic low back pain, vulvodynia, fibromyalgia, temporomandibular joint disease, and chronic fatigue syndrome), mood conditions (defined as depression and anxiety), and asthma. RESULTS: Comorbid pain syndromes were found in 77 (56%) women, mood conditions in 66 (48%) women, and asthma in 31 (26%) women. Comparing endometriosis patients with and without comorbid pain syndromes, no differences were found in age at time of diagnosis, endometriosis symptoms, and endometriosis stage. Patients with comorbid pain syndromes were more likely to report mood conditions (62% vs 30% respectively, P < .001) and smoking (31% vs 10% respectively, P = .003), underwent more surgeries for endometriosis (median of 2 [range, 1-7] vs 1 [range, 1-5], P < .005), and were more likely to undergo appendectomy or cholecystectomy (30% vs 13%, P = .02). CONCLUSIONS: Comorbid pain syndromes, mood conditions and asthma are common in adolescents and young women with endometriosis.
What is evaluated using the EORTC QLQ – INFO25 questionnaire?
The European Organisation for Research and Treatment of Cancer Quality of Life Group information questionnaire (EORTC QLQ-INFO 25) evaluates the level of information patients have received in different areas of their disease, treatment and care, and evaluates qualitative aspects together with satisfaction with information.
Information is one of the main interventions given to cancer patients. Important research into information disclosure has been conducted and major advances have been made. We present the main theoretical models used to understand the information field and describe the current situation regarding the principal factors related to information: patients' needs, coping strategies, illness representations, cross-cultural differences, the role of the family, and strategies to enhance information giving, such as professional training and patient-targeted interventions. We highlight the need to assess patients' characteristics and desires through questionnaires and interviews and present the European Organisation for Research and Treatment of Cancer Quality of Life Group information questionnaire (EORTC QLQ-INFO 25). This instrument evaluates the level of information patients have received in different areas of their disease, treatment and care, and evaluates qualitative aspects. Finally, we describe the key areas of the information field and discuss how these areas could change in the future. INTRODUCTION: The EORTC QLQ-INFO25 evaluates the information received by cancer patients. This study assesses the psychometric properties of the QLQ-INFO25 when applied to a sample of Spanish patients. MATERIALS AND METHODS: A total of 169 patients with different cancers and stages of disease completed the EORTC QLQINFO25, the EORTC QLQ-C30 and the information scales of the inpatient satisfaction module EORTC IN-PATSAT32 on two occasions during the patients' treatment and follow- up period. Psychometric evaluation of the structure, reliability, validity and responsiveness to changes was conducted. Patient acceptability was assessed with a debriefing questionnaire. RESULTS: Multi-trait scaling confirmed the 4 multi-item scales (information about disease, medical tests, treatment and other services) and eight single items. All items met the standards for convergent validity and all except one met the standards of item discrimit validity. Internal consistency for all scales (α>0.70) and the whole questionnaire (α>0.90) was adequate in the three measurements, except information about the disease (0.67) and other services (0.68) in the first measurement, as was test-retest reliability (intraclass correlations >0.70). Correlations with related areas of IN-PATSAT32 (r>0.40) supported convergent validity. Divergent validity was confirmed through low correlations with EORTC QLQ-C30 scales (r<0.30). The EORTC QLQ-INFO-25 discriminated among groups based on gender, age, education, levels of anxiety and depression, treatment line, wish for information and satisfaction. One scale and an item showed changes over time. CONCLUSIONS: The EORTC QLQ-INFO 25 is a reliable and valid instrument when applied to a sample of Spanish cancer patients. These results are in line with those of the EORTC validation study. OBJECTIVE: Informational needs among cancer patients are similar, but the degree of information disclosure in different cultural areas varies. In this paper, we present the results of a cross-cultural study on information received. METHODS: The EORTC information questionnaire, EORTC QLQ-INFO25, was administered during the treatment process. This questionnaire evaluates the information that patients report they have received. Cross-cultural differences in information have been evaluated using statistical tests such as Kruskall-Wallis and multivariate models with covariates to account for differences in clinical and demographic characteristics across areas. RESULTS: Four hundred and fifty-one patients from three cultural areas, North-Middle Europe, South Europe, and Taiwan, were included in the study. Significant differences among the three cultural areas appeared in eight QLQ-INFO25 dimensions: information about the disease; medical tests; places of care; written information; information on CD/tape/video; satisfaction; wish for more information; and information helpfulness. North-Middle Europe patients received more written information (mean = 67.2 (North) and 33.8 (South)) and South Europe patients received more information on different places of care (mean = 24.7 (North) and 35.0 (South)). Patients from North-Middle Europe and South Europe received more information than patients from Taiwan about the disease (mean = 57.9, 60.6, and 47.1, respectively) and medical tests (70.9, 70.4, and 54.5), showed more satisfaction (64.8, 70.2, and 35.0), and considered the information more helpful (71.9, 73.9, and 50.4). These results were confirmed when adjusting for age, education, and disease stage. CONCLUSION: There are cross-cultural differences in information received. Some of these differences are based on the characteristics of each culture. BACKGROUND: Information is vital to cancer patients. Physician-patient communication in oncology presents specific challenges. The aim of this study was to evaluate self-reported information of cancer patients in ambulatory care at a comprehensive cancer centre and examine its possible association with patients' demographic and clinical characteristics. PATIENTS AND METHODS: This study included adult patients with solid tumours undergoing chemotherapy at the Institute Jules Bordet's Day Hospital over a ten-day period. EORTC QLQ-C30 and QLQ-INFO25 questionnaires were administered. Demographic and clinical data were collected. Descriptive and inferential statistics were used. RESULTS: 101 (99%) fully completed the questionnaires. They were mostly Belgian (74.3%), female (78.2%), with a mean age of 56.9 ± 12.8 years. The most frequent tumour was breast cancer (58.4%). Patients were well-informed about the disease and treatments, but presented unmet information domains. The Jules Bordet patients desired more information on treatment side effects, long-term outcome, nutrition, and recurrence symptoms. Patients on clinical trials reported having received less information about their disease and less written information than patients outside clinical trials. Higher information levels were associated with higher quality of life (QoL) scores and higher patient satisfaction. CONCLUSION: Patients were satisfied with the information they received and this correlated with higher QoL, but they still expressed unmet information wishes. Additional studies are required to investigate the quality of the information received by patients enrolled in clinical trials. INTRODUCTION: Developing a tool for measuring patient's needs is a vital step in the process of cancer treatment and research. In recent years, the European Organization for Research and Treatment of Cancer (EORTC) made a questionnaire to measure cancer patients' received information. Since validity and reliability of any instrument should be evaluated in the new environment and culture, the aim of this study was to assess the validity and reliability of the EORTC QLQ-INFO25 in Iranian cancer patients. MATERIALS AND METHODS: One hundred seventy-three patients with different stages of cancer filled questionnaire EORTC QLQ-INFO25, EORTC QLQ-C30, and EORTC IN-PATSAT32. Twenty-five patients answered the questionnaire twice at an interval of 2 weeks. Reliability and validity of the questionnaire was measured by Cronbach's alpha, interclass correlation, test retest, inter-rater agreement (IRA), and exploratory factorial analyses. RESULTS: Using a conservative approach, the IRA for the overall relevancy and clarity of the tool was 87/86% and 83.33%, respectively. Overall appropriateness and clarity were 94.13 and 91.87%, respectively. Overall integrity of the instrument was determined to be 85%. Cronbach's alpha coefficients for all domains and total inventory were top 70 and 90%, respectively. Interclass correlation index ranges between 0.708 and 0.965. Exploratory factorial analyses demonstrate six fields suitable for instrument. Correlation between areas of the questionnaires EORTC QLQ-INFO25 and EORTC in-Patsat32 represents the convergent validity of the questionnaire. Also, results show a standard divergent validity in all domains of the questionnaire (Rho <0.3). Low correlation between the areas of the questionnaires EORTC QLQ-INFO25 and EORTC QLQ-C30 (<0.3) demonstrates the divergence validity of the questionnaire. CONCLUSION: The results showed that Persian version of the questionnaire EORTC QLQ-INFO25 is a reliable and valid instrument for measuring the perception of information in cancer patients.
Does BNP increase after intensive exercise in athletes?
BNP and NTproBNP increase early after exercise in healthy athletes performing different types of sports. It is unknown the reason of this increase. The transient increases in BNP, NT-pro-BNP and troponin T are more likely to reflect myocardial stunning than cardiomyocyte damage.
BACKGROUND: Now that marathon racing is growing in popularity, many thousands of enthusiastic athletes are participating in various ultramarathons all over the world each year. However, it remains controversial whether such a sport contributes to the promotion of health. The occurrence of transient cardiac dysfunction and irreversible myocardial injury has been reported in association with such exercise in healthy individuals. Brain natriuretic peptide (BNP) is a cardiac hormone, as is atrial natriuretic peptide (ANP), and its measurement has been widely used for clinical evaluation of cardiac dysfunction. However, little is known about the response of plasma BNP to prolonged strenuous exercise. We hypothesized that confirmation of minimal cardiac dysfunction or myocardial injury may be made by measurements of plasma BNP. METHODS: Levels of plasma ANP, BNP, catecholamines, blood lactate, and serum cardiac troponin T (cTnT) were determined before and after a 100-km ultramarathon in 10 healthy men to examine the effects of the exercise on levels of ANP and BNP and correlations between the natriuretic peptides and cTnT as a marker for myocardial damage. RESULTS: Whereas all variables significantly increased after the race, increased levels of ANP and BNP were most strongly correlated with increases in cTnT levels. The cTnT level after the race was greater than the upper reference limit in 9 of 10 men. CONCLUSIONS: Such exercise significantly increased ANP and BNP levels in healthy men, and the increases could be partially attributed to myocardial damage during the race. The echocardiographic measures and plasma concentrations of either atrial natriuretic peptide (ANP) or brain natriuretic peptide (BNP) were compared in elite judo practitioners (static athletes), elite marathon runners (dynamic athletes) and healthy controls to investigate the relationship between the different types of left ventricular (LV) hypertrophy and plasma concentrations of natriuretic peptides in athletes. The LV mass and LV wall thickness of marathon runners and judo practitioners were significantly greater than those of controls. The LV end-diastolic dimension index was significantly larger in the marathon group, but smaller in the judo group. The left atrial dimension (LAD) index was significantly larger only in marathon runners. Plasma BNP concentrations were higher in both the judo and marathon groups than in controls, and positively correlated with LV mass as well as with deceleration time. Plasma ANP concentrations were significantly higher in marathon runners than in the controls and judo groups, and positively correlated with the LAD index, but negatively correlated with ejection fraction. Multivariate analyses showed that the type of athlete and LAD index were independent predictors of plasma BNP and ANP concentrations, respectively. Thus, there is an intimate link between plasma concentrations of natriuretic peptides and cardiac morphology in different types of athletes. For a further depiction of exercise-induced cardiac dysfunction, N-terminal pro-brain natriuretic peptide (NT-pro-BNP) and cardiac troponin T (cTnT) were measured in recreational cyclists (n = 29) during the Otztal Radmarathon 2004. In all subjects, NT-pro-BNP significantly increased from 28 +/- 21 to 278 +/- 152 ng/L immediately after the race (p <0.001), decreased again on the following day, and returned to baseline values 1 week later. The mean percentage increase in NT-pro-BNP was 1,128 +/- 803%. CTnT, negative in all subjects before the race, increased transiently in 13 athletes (45%), with levels ranging from 0.043 to 0.224 mug/L in 8 of them (28%). One day after competition, cTnT had normalized in all athletes. Because of the typical release of kinetics, the deflection of NT-pro-BNP is considered to be the adequate volume regulatory response of a hemodynamically stressed heart to prolonged strenuous exercise. The observed kinetics of cTnT substantiate a release from the free cytoplasmatic pool due to the half-life of cytosolic cTnT. In healthy cyclists, transient increases in NT-pro-BNP and cTnT are more likely to reflect cardiac fatigue than injury. BACKGROUND: Although elevated resting brain natriuretic peptide (BNP) concentrations reflect heart disease, the meaning of exercise-induced increases is poorly understood and has been examined in small groups only. Therefore, the present study aimed to examine the increase in N-terminal pro-brain natriuretic peptide (NT-proBNP) and relations to cardiac troponin I and T (cTnI, cTnT) elevations after prolonged strenuous exercise in a large cohort of athletes. METHODS: We examined exercise-induced changes in NT-proBNP, cTnI, and cTnT in 105 obviously healthy endurance athletes (40 +/- 8 years) before and after prolonged strenuous exercise. Blood samples were taken before, 15 minutes, and 3 hours after a marathon (n = 46), a 100-km run (n = 14), and a mountain bike marathon (n = 45). RESULTS: Eighty-one of 105 athletes exceeded the upper reference limit of NT-proBNP (males/females 88:153 ng/L) after exercise. NT-proBNP increased in all 3 events (P < .001) with the highest increase in the 100-km runners (median increase 200 ng/L; 25th/75th percentile 115/770 ng/L), which differed from the increase in the marathon (97 ng/L; 36/254 ng/L) or the mountain bike marathon (78 ng/L; 37/196 ng/L) (P < .01). Cardiac troponin I exceeded 0.04 microg/L in 74%; cTnT exceeded 0.01 microg/L in 47% of athletes after exercise. NT-proBNP was not related to exercise-induced increases in cTnI or cTnT, but correlated with exercise time (r = 0.55, P < .001). CONCLUSIONS: Increases in NT-proBNP can be found in a major part of obviously healthy athletes after prolonged strenuous exercise. The release of BNP during and after exercise may not result from myocardial damage but may have cytoprotective and growth-regulating effects. The different nature of exercise-induced increases in BNP and cardiac troponins has to be elucidated in the future. AIM: Brain natriuretic peptide (BNP) is a cardioactive molecule produced in the myocardium. BNP is a sensitive marker of cardiac failure and its measurement in blood could be useful to the diagnosis and the treatment of this disease. Sporting activities, especially endurance ones, can induce cardiac problems, owing to the high workload for the myocardium during long and ultralong heavy effort. There are 2 papers describing the behavior of BNP in endurance events. BNP was elevated in marathoners, immediately after the race and also after 4 h. We studied the behavior of BNP in the triathlon, which is a complex sport characterized by 3 different activities (swimming, cycling, running). METHODS: We recruited 49 athletes, all males, except for 4 females; 2 athletes did not finish the race and were not included in the statistical analysis in 2 different competitions. In these subjects we measured BNP using an immunological method before and after a triathlon. RESULTS: No statistical significance between BNP values, before and after the triathlon, was found. CONCLUSIONS: We found no significant differences between pre- and postcompetition BNP values. Moreover, the range of values in both the blood drawings are similar of those of the general population, representing the biological variability of the analyte. The values in regularly trained athletes,, are not different from the general population and BNP is not modified by a triathlon, a typical endurance sport performance. We can underline that BNP increases in plasma are induced by heavy pathologies and are not influenced by physical activities, even strenuous ones. The aim of this study was to examine cardiac dysfunction following ultra-endurance exercise in male athletes. Fourteen athletes (mean+/-SD, age 39+/-8 years) were evaluated before and after the European Championship in Triathlon 2003 using echocardiogram (ECG), cardiac markers [cardiac troponin T (cTnT) and pro-brain natriuretic peptide (pro-BNP)] and echocardiography. Conventional echocardiography techniques and new Doppler tissue imaging (DTI) modalities were applied before and immediately after the competition. Blood samples were drawn 1 week before, immediately after and 12-24 h post-competition. CTnT significantly increased immediately, but decreased to within normal limits 12-24 h post-competition. Pro-BNP was significantly increased immediately post-race (27+/-21 vs 7+/-2 pmol/L pre-race, P < or = 0.007), which 12-24 h later, decreased to 19+/-14 pmol/L (P = 0.07 vs pre-race). During echocardiography, no significant differences were found in regional or global systolic parameters. Early diastolic peak flow velocity (9+/-2, P = 0.04) and E/A ratio (2+/-1, P = 0.004) were increased pre-race and decreased significantly toward normal values. In one athlete, cTnT levels increased significantly and systolic velocities decreased, thus suggesting reversible cardiac fatigue. When using cardiac markers and echocardiographic findings, a triathlon was found to have no significant negative effects on left ventricular function or myocardial tissue in male athletes. PURPOSE: Transient cardiac ventricular dysfunction or sudden cardiac deaths have been reported for male athletes participating in marathon racing. Less is known about the myocardial response in females. We examined natriuretic peptides and cardiac troponins in female athletes after a marathon. METHODS: At the 31st real,- Berlin Marathon plasma levels of NT-pro-BNP, BNP, cTnI and cTnT were measured in 15 women (age 35+/-6 years; finishing times between 3:22 h and 5:21 h) at four different time points (before, immediately after, day one and day three). RESULTS: An increase in [NT-pro-BNP] was observed immediately after the marathon (median [NT-pro-BNP] before: 39.6 pg ml(-1), after: 138.6 pg ml(-1), p=0.003) with a further increase on day one. [BNP] did not increase immediately after the marathon but increased on day one (median [BNP] before: 15 pg ml(-1), day one: 27.35 pg ml(-1), p=0.006). On day three, [NT-pro-BNP] and [BNP] returned to initial values. [cTnI] was under the detection limit prior to the marathon in all runners. [cTnT] was under the detection limit before the marathon except in one runner who presented a concentration of 0.03 ng ml(-1). Cardiac troponins (median [cTnl] after: 0.098 ng ml(-1), p=0.028; median [cTnT] after: 0.032 ng ml(-1), p=0.012) increased immediately after the marathon and returned to initial values on day one [cTnT] and three [cTnI]. DISCUSSION: Parameters representing cardiac stress increased in females after a marathon. Different kinetics of natriuretic peptides BNP and NT-pro-BNP post-marathon could be due to their different half-lives and dependence on renal function. The increase of cTnI and cTnT may result from minor myocardial lesions. PURPOSES: To comprehensively investigate the cardiovascular consequences of a 160-km ultramarathon using traditional echocardiography, speckle tracking imaging, cardiac biomarkers, and heart rate variability (HRV) and to examine the relationship between the changes in these variables. METHODS: We examined athletes before an ultramarathon and reassessed all finishers immediately after the race. Left ventricular (LV) systolic (ejection fraction [EF], systolic blood pressure/end-systolic volume [SBP/ESV] ratio) and diastolic (ratio of early [E] to late [A], filling E:A) measurements were assessed using traditional echocardiography, whereas myocardial peak strain and strain rate were analyzed using speckle tracking. Cardiac biomarkers measured were cardiac troponin T (cTnT) and N-terminal pro-brain natriuretic peptide (NT-pro-BNP). HRV indices were assessed using standard frequency and time domain measures. RESULTS: Twenty-five athletes successfully completed the race (25.5 +/- 3.2 h). Significant pre- to postrace changes in EF (66.8 +/- 3.8 to 61.2 +/- 4.0 %, P < 0.05) and E:A ratio (1.62 +/- 0.37 to 1.35 +/- 0.33, P < 0.05) were reported. Peak strain was significantly decreased in all planes, with the largest reduction occurring circumferentially. NT-pro-BNP concentrations increased significantly (28 +/- 17.1 vs 795 +/- 823 ng x L, P < 0.05), whereas postrace cTnT were elevated in just five athletes (20%). No significant alterations in HRV were noted postrace. Reductions in LV function were not significantly associated with changes in cardiac biomarkers and/or HRV. CONCLUSIONS: Although the stress of an ultramarathon resulted in a mild reduction in LV function and biomarker release, the mechanisms behind such consequences remain unknown. It is likely that factors other than myocardial damage or strong vagal reactivation contributed to postexercise decreases in LV function after an ultramarathon.
What is the association of estrogen replacement therapy and intracranial meningioma risk?
The association between hormone replacement therapy and meningioma risk is controversial. Increased risk of meningioma was demonstrated in estrogen-only hormonal replacement therapy. However, other studies did not find an association between hormonal replacement therapy and meningioma risk.
Meningiomas are slow-growing benign brain tumors. The etiology of meningioma is largely unknown, and exposure to high-dose ionizing radiation and coexistence with certain rare genetic conditions explain only a small fraction of the incidence of the disease. The evidence that implicates gender-specific hormones in the pathogenesis of meningioma emanates from data showing increased growth of meningiomas during pregcy and change in size during menses. Observational data have identified the menopause and oophorectomy as conferring protection against the risk of developing meningiomas, while adiposity is positively associated with the disease. These tumors are also positively associated with breast cancer, although they express a different gonadal steroid receptor repertoire. About 70% of meningiomas express progesterone receptors, while fewer than 31% express estrogen receptors. These observations suggest that progesterone influences tumor growth. A progesterone antagonist such as mifepristone therefore may inhibit tumor growth. The use of hormone replacement therapy in symptomatic postmenopausal women either with previously treated disease or with dormant tumors is discussed, but remains controversial. Meningiomas occur more commonly in females. The coincidence between meningioma and breast cancer and case reports of tumor growth during pregcy support a hormonal hypothesis. A case control study was conducted to investigate this. Female subjects treated between 1987 and 1992 were identified from 3 hospitals in the Chicago area. Female spouses of male back pain patients were recruited as controls. A self-administered mail questionnaire focused on exogenous, endogenous and other hormonal factors, personal and family medical history as well as radiation exposures. Odds ratios and 95% confidence intervals were estimated using crude, stratified and multivariable logistic models including 219 cases and 260 controls. Participation rates were 86% among cases and 75% among controls. An increased odds ratio (OR) was observed comparing African Americans to Caucasians [OR = 2.4, 95% confidence interval (CI) = 1.0-6.1]. A protective effect was observed for pregcy, which increased with number and age at first pregcy. The odds ratio for 3 or more pregcies compared to none was 0.3 (95% CI = 0.2-0.6). Age at menarche or total period of hormonal activity was not protective. Ever smokers showed a decreased odds ratio for meningioma (OR = 0.6, 95% CI = 0.4-0.9). The increased odds ratios with African Americans was retained in post-menopausal women, while the protective odds ratios for pregcy, smoking and oral contraceptives (OCs) became stronger in pre-menopausal women. The pattern by duration and timing of use does not suggest an etiologic role for OCs or hormone replacement therapy. These data add to the evidence that factors known to influence endogenous hormones (pregcy and indirectly smoking) may have protective effects for meningiomas primarily in premenopausal women. The decision to commence or continue use of hormone replacement therapy or oral contraceptives in women presumed or known to be diagnosed with intracranial meningioma is a common clinical question in neurosurgery. A review of the English-language literature was undertaken to examine the association between the use of exogenous hormones and meningioma risk. Seven publications were identified, 6 of which met criteria for inclusion. No randomized clinical trial data were available, hence, results were collected from 2 population-based case-control studies, 2 hospital-based case-control studies, 1 nested case-control study drawn from a large national cohort, and 1 retrospective cohort study. At present, there is no statistical evidence of an increased risk of meningioma among users of oral contraceptives. Although not definitive, available data suggest an association between the use of hormone replacement therapy and increased meningioma risk. Further evaluation of exogenous hormone use in women with meningioma is needed with particular attention to stratification by hormone (ie, estrogen and/or progesterone) composition, duration of and age at use as well as tumor receptor subtype. We examined the relation between the use of hormone replacement therapy (HRT) and the incidence of central nervous system (CNS) tumours in a large prospective study of 1,147,894 postmenopausal women. Women were aged 56.6 years on average at entry, and HRT use was recorded at recruitment and updated, where possible, about 3 years later. During a mean follow-up of 5.3 years per woman, 1,266 CNS tumours were diagnosed, including 557 gliomas, 311 meningiomas and 117 acoustic neuromas. Compared with never users of HRT, the relative risks (RRs) for all incident CNS tumours, gliomas, meningiomas and acoustic neuromas in current users of HRT were 1.20 (95% CI: 1.05-1.36), 1.09 (95% CI: 0.89-1.32), 1.34 (95% CI: 1.03-1.75) and 1.58 (95% CI: 1.02-2.45), respectively, and there was no significant difference in the relative risks by tumour type (heterogeneity p = 0.2). In past users of HRT the relative risk was 1.07 (95% CI: 0.93-1.24) for all CNS tumours. Among current users of HRT, there was significant heterogeneity by the type of HRT with the users of oestrogen-only HRT at higher risk of all CNS tumours than users of oestrogen-progestagen HRT (RR = 1.42, 95% CI: 1.21-1.67 versus RR = 0.97, 95% CI: 0.82-1.16) (heterogeneity p < 0.001). Among current users of oestrogen-only and oestrogen-progestagen HRT, there was no significant heterogeneity by duration of use, hormonal constituent or mode of administration of HRT. BACKGROUND: Previous studies on association of exogenous female sex hormones and risk for meningioma have yielded conflicting results. The aim of this study was to evaluate the potential relation between prior use of menopausal hormone therapy or oral contraception and risk of meningioma. METHODS: This population-based case-control study was conducted during years 2000-2002 in Finland. All women aged 20-69 years with meningioma diagnosis were identified from five university hospitals, and frequency-matched controls were randomly chosen from population register. A total of 264 cases and 505 controls were interviewed on their use of menopausal hormone therapy, oral and other contraception, fertility treatment, treatment for gynecological problems, age at menarche, and number of children. We also analyzed separately tumors expressing progesterone or estrogen receptors. Of the successfully stained tumor specimens, 86.3% were positive for progesterone receptor and 50% for estrogen receptor. RESULTS: Postmenopausal hormonal treatment, use of contraceptives, or fertility treatment did not influence the risk of meningioma. In further analysis by hormone receptor status, there was some indication for an increased risk of progesterone receptor-positive meningiomas associated with oral contraceptive use (OR 1.39, 95% confidence interval 0.92-2.10) and other hormonal contraception (OR 1.50, 95% CI 0.95-2.36). CONCLUSIONS: Overall, we found little indication that reproductive factors or use of exogenous sex hormones affect meningioma risk. A retrospective study including more than 350,000 women, about 1400 of whom had developed meningioma, showed that the risk of meningioma was about twice as high in users of postmenopausal hormone replacement therapy as in non-users. Hormone replacement therapy should be discontinued if meningioma is diagnosed. The authors conducted a nationwide cohort study to evaluate the association between postmenopausal hormone therapy and meningioma incidence in Finland. All women who had used hormone therapy at least for 6 months at the age of 50 years or older during 1994-2009 were included. Women who had used postmenopausal hormone therapy were identified from the medical reimbursement register of the Social Insurance Institution (131,480 estradiol users and 131,248 estradiol-progestin users), and meningioma cases were identified from the Finnish Cancer Registry. During the average 9 years of follow-up, 289 estradiol users and 196 estradiol-progestin users were diagnosed with meningioma. Ever use of estradiol-only therapy was associated with an increased risk of meningioma (standardized incidence ratio = 1.29, 95% confidence interval: 1.15, 1.44). Among women who had been using estradiol-only therapy for at least 3 years, the incidence of meningioma was 1.40-fold higher (95% confidence interval: 1.18, 1.64; P < 0.001) than in the background population. In contrast, this risk was not increased in users of combination therapy (standardized incidence ratio = 0.93, 95% confidence interval: 0.80, 1.06). There was no difference in risk between continuous and sequential use of hormone therapy. Estradiol-only therapy was accompanied with a slightly increased risk of meningioma. OBJECT: The 2-fold higher incidence of meningioma in women compared with men has long suggested a role for hormonally mediated risk factors, but specific mechanisms remain elusive. METHODS: The study included data obtained in 1127 women 29-79 years of age with intracranial meningioma diagnosed among residents of Connecticut, Massachusetts, North Carolina, the San Francisco Bay Area, and 8 Texas counties between May 1, 2006, and October 6, 2011, and data obtained in 1092 control individuals who were frequency matched for age group and geography with meningioma patients. RESULTS: No association was observed for age at menarche, age at menopause, or parity and meningioma risk. Women who reported breastfeeding for at least 6 months were at reduced risk of meningioma (OR 0.78, 95% CI 0.63-0.96). A significant positive association existed between meningioma risk and increased body mass index (p < 0.01) while a significant negative association existed between meningioma risk and current smoking (p < 0.01). Among premenopausal women, current use of oral contraceptives was associated with an increased risk of meningiomas (OR 1.8, 95% CI 1.1-2.9), while current use of hormone replacement therapy among postmenopausal women was not associated with a significant elevation in risk (OR 1.1, 95% CI 0.74-1.67). There was no association between use of fertility medications and meningioma risk. CONCLUSIONS: The authors' study confirms associations for body mass index, breastfeeding, and cigarette smoking but provides little evidence for associations of reproductive and menstrual factors with meningioma risk. The relationship between current use of exogenous hormones and meningioma remains unclear, limited by the small numbers of patients currently on oral hormone medications and a lack of hormone receptor data for meningioma tumors. AIM: Several studies indicate that use of hormone replacement therapy (HRT) is associated with an increased risk of intracranial meningioma, while associations between HRT use and risk of other brain tumors have been less explored. We investigated the influence of HRT use on the risk of glioma in a nationwide setting. METHODS: Using population-based registries we conducted a case-control study nested in the Danish female population. We identified all women aged 55-84 years with a first diagnosis of histologically verified brain glioma during 2000-2009. Using risk-set sampling, each case was matched on birth year to eight population controls. Ever use of HRT was defined as ≥2 HRT prescriptions and categorized according to type (oestrogens only, combined oestrogen-progestagen and progestagen only) and duration of use (<1, ≥1 to <5, ≥5 to <10, and ≥10 years). We used conditional logistic regression to compute odds ratios (ORs), with 95% confidence intervals (CIs), for glioma associated with HRT use, adjusting for potential confounders. RESULTS: We identified 658 cases and 4350 controls. Ever use of HRT was associated with an OR of 0.9 (95% CI: 0.8-1.1) for glioma. For long-term use (≥10 years) we found ORs of 1.1 (95% CI: 0.7-1.7) for HRT overall, 1.6 (95% CI: 0.9-2.6) for oestrogen only, 0.8 (0.4-1.6) for combined oestrogen-progestagen, and 2.2 (0.9-5.5) for progestagen. Tests for trends were statistically non-significant in all strata. CONCLUSION: Use of HRT overall was not associated with an increased risk of glioma. However, our findings indicate that prolonged use of oestrogen only or progestagen may be associated with an increased risk of glioma. Female sex hormones are thought to affect women's risk of developing central nervous system (CNS) tumors. Some have reported an increased risk in users of menopausal hormone therapy (HT) but evidence is limited. In the UK General Practice Research Database we compared prospectively collected information on HT prescriptions in women aged 50-79 years with CNS tumors diagnosed in 1987-2011 with that in matched controls (four per case). Relative risks (RRs) in relation to prescribed HT were calculated overall and by CNS tumor subtype. Statistical tests are two-sided. For all CNS tumors (n = 3,500), glioma (n = 689), meningioma (n = 1,197), acoustic neuroma (n = 439), and pituitary tumors (n = 273) adjusted RRs for women prescribed HT versus not were, respectively, 1.21 (95% confidence intervals (CI) = 1.10-1.32, p < 0.0001), 1.14 (0.93-1.40, p = 0.2), 1.30 (1.11-1.51, p = 0.001), 1.37 (1.06-1.75, p = 0.01), and 1.35 (0.99-1.85, p = 0.06). There was no significant difference in risk by tumor subtype (p(heterogeneity) = 0.6). A meta-analysis was conducted, combining our results with those from other published studies with prospectively collected exposure information. The meta-analyses yielded significantly increased risks for all CNS tumors, glioma and meningioma in users of estrogen-only [1.35 (1.22-1.49), 1.23 (1.06-1.42) and 1.31 (1.20-1.43), respectively] but not estrogen-progestin HT [1.09 (0.99-1.19), 0.92 (0.78-1.08) and 1.05 (0.95-1.16), respectively]; these differences were statistically significant (p < 0.005 for each tumor type). There was no significant difference between glioma and meningioma risk in users of estrogen-only HT. The totality of the available evidence suggests an increased risk of all CNS tumors (and of glioma and meningioma separately) in users of estrogen-only HT. Absolute excess risk (2 per 10,000 users over 5 years) is small.
Are there web based self management strategies for chronic pain ?
Results suggest the potential value of self-management for chronic pain patients and the potential acceptability of web-based delivery of intervention content.
BACKGROUND: Internet-based interventions are increasingly used to support self-management of individuals with chronic illnesses. Web-based interventions may also be effective in enhancing self-management for individuals with chronic pain, but little is known about long-term effects. Research on Web-based interventions to support self-management following participation in pain management programs is limited. OBJECTIVE: The aim is to examine the long-term effects of a 4-week smartphone-intervention with diaries and therapist-written feedback following an inpatient chronic pain rehabilitation program, previously found to be effective at short-term and 5-month follow-ups. METHODS: 140 women with chronic widespread pain, participating in a 4-week inpatient rehabilitation program, were randomized into two groups: with or without a smartphone intervention after the rehabilitation. The smartphone intervention consisted of one face-to-face individual session and 4 weeks of written communication via a smartphone, consisting of three diaries daily to elicit pain-related thoughts, feelings, and activities, as well as daily personalized written feedback based on cognitive behavioral principles from a therapist. Both groups were given access to an informational website to promote constructive self-management. Outcomes were measured with self-reported paper-and-pencil format questionnaires with catastrophizing as the primary outcome measure. Secondary outcomes included daily functioning and symptom levels, acceptance of pain, and emotional distress. RESULTS: By the 11-month follow-up, the favorable between-group differences previously reported post-intervention and at 5-month follow-up on catastrophizing, acceptance, functioning, and symptom level were no longer evident (P>.10). However, there was more improvement in catastrophizing scores during the follow-up period in the intervention group (M=-2.36, SD 8.41) compared to the control group (M=.40, SD 7.20), P=.045. Also, per protocol within-group analysis showed a small positive effect (Cohen's d=.33) on catastrophizing in the intervention group (P=.04) and no change in the control group from the smartphone intervention baseline to 11-month follow-up. A positive effect (Cohen's d=.73) on acceptance was found within the intervention group (P<.001) but not in the control group. Small to large negative effects were found within the control group on functioning and symptom levels, emotional distress, and fatigue (P=.05) from the intervention baseline to the 11-month follow-up. CONCLUSION: The long-term results of this randomized trial are ambiguous. No significant between-group effect was found on the study variables at 11-month follow-up. However, the within-group analyses, comparing the baseline for the smartphone intervention to the 11-month data, indicated changes in the desired direction in catastrophizing and acceptance in the intervention group but not within the control group. This study provides modest evidence supporting the long-term effect of the intervention. TRIAL REGISTRATION: Clinicaltrials.gov NCT01236209; http://www.clinicaltrials.gov/ct2/show/NCT01236209 (Archived by WebCite at http://www.webcitation.org/6FF7KUXo0). BACKGROUND: Chronic low back pain is a common chronic condition whose treatment success can be improved by active involvement of patients. Patient involvement can be fostered by web-based applications combining health information with decision support or behaviour change support. These so-called Interactive Health Communication Applications (IHCAs) can reach great numbers of patients at low ficial cost and provide information and support at the time, place and learning speed patients prefer. However, high attrition often seems to decrease the effects of web-based interventions. Tailoring content and tone of IHCAs to the individual patient ́s needs might improve usage and therefore effectiveness. This study aims to evaluate a tailored IHCA for people with chronic low back pain combining health information with decision support and behaviour change support. METHODS/DESIGN: The tailored IHCA will be tested regarding effectiveness and usage against a standard website with identical content in a single-blinded randomized trial with a parallel design. The IHCA contains information on chronic low back pain and its treatment options including health behaviour change recommendations. In the intervention group the content is delivered in dialogue form, tailored to relevant patient characteristics (health literacy, coping style). In the control group there is no tailoring, a standard web-page is used for presenting the content. Participants are unaware of group assignment. Eligibility criteria are age ≥ 18 years , self- reported chronic low back pain, and Internet access. To detect the expected small effect (Cohen's d = 0.2), the sample aims to include 414 patients, with assessments at baseline, directly after the first on-page visit, and at 3-month follow-up using online self-report questionnaires. It is expected that the tailored IHCA has larger effects on knowledge and patient empowerment (primary outcomes) compared to a standard website. Secondary outcomes are website usage, preparation for decision making, and decisional conflict. DISCUSSION: IHCAs can be a suitable way to promote knowledge about chronic low back pain and self-management competencies. Results of the study can increase the knowledge on how to develop IHCAs which are more useful and effective for people suffering from chronic low back pain. TRIAL REGISTRATION: International Clinical Trials Registry DRKS00003322. OBJECTIVES: To describe the development of an interactive, web-based self-management intervention for opioid-treated, chronic pain patients with aberrant drug-related behavior. METHODS: Fifty-three chronic pain patients participated in either focus groups (N = 23) or individual feedback sessions (N = 30). Focus groups probed interest in and relevance of the planned content and structure of the program. Individual session participants reviewed draft program modules and provided feedback on acceptability, ease of use, and usefulness. Focus group transcripts were thematically analyzed, and summary statistics were performed on feedback data. RESULTS: Focus group participants stressed the need for additional pain management strategies and emphasized themes consistent with planned program content related to: 1) ambivalence about opioids; 2) reciprocal relationships among cognition, mood, and pain; 3) importance of recognizing physical limitations; and 4) effectiveness of goal setting for increasing motivation and functioning. Participants also offered insights on: 5) the loss of identity due to chronic pain; and 6) the desire to connect with pain peers to share strategies for managing daily life. Feedback session data demonstrate that participants believed that a web-based tool would be potentially useful and acceptable, and that exposure to program sections significantly increased participants' knowledge of key topics related to self-management of chronic pain. CONCLUSIONS: Results suggest the potential value of self-management for chronic pain patients and the potential acceptability of web-based delivery of intervention content. Focus group and feedback methodologies highlight the usefulness of including potential program users in intervention development. BACKGROUND: It is estimated that 30% of adults in the United States experience daily chronic pain. This results in a significant burden on the health care system, in particular primary care, and on the workplace. Chronic pain management with cognitive-behavioral psychological treatment is effective in reducing pain intensity and interference, health-related quality of life, mood, and return to work. However, the population of individuals with chronic pain far exceeds the population of therapists that can provide this care face-to-face. The use of tailored, Web-based interventions for the management of chronic pain could address limitations to access by virtue of its unlimited scalability. OBJECTIVE: To examine the effects of a tailored Web-based chronic pain management program on subjective pain, activity and work interference, quality of life and health, and stress. METHODS: Eligible participants accessed the online pain management program and informed consent via participating employer or health care benefit systems; program participants who completed baseline, 1-, and 6-month assessments were included in the study. Of the 645 participants, the mean age was 56.16 years (SD 12.83), most were female (447/645, 69.3%), and white (505/641, 78.8%). Frequent pain complaints were joint (249/645, 38.6%), back (218/645, 33.8%), and osteoarthritis (174/654, 27.0%). The online pain management program used evidence-based theories of cognitive behavioral intervention, motivational enhancement, and health behavior change to address self-management, coping, medical adherence, social support, comorbidities, and productivity. The program content was individually tailored on several relevant participant variables. RESULTS: Both pain intensity (mean 5.30, SD 2.46), and unpleasantness (mean 5.43, SD 2.52) decreased significantly from baseline to 1-month (mean 4.16, SD 2.69 and mean 4.24, 2.81, respectively) and 6-month (mean 3.78, SD 2.79 and mean 3.78, SD 2.79, respectively) assessments (P<.001). The magnitude of the 6-month effects were large. Trends for decreases in pain interference (36.8% reported moderate or enormous interference) reached significance at 6 months (28.9%, P<.001). The percentage of the sample reporting fair or poor quality of life decreased significantly from 20.6% at baseline to 16.5% at 6 months (P=.006). CONCLUSIONS: Results suggest that the tailored online chronic pain management program showed promising effects on pain at 1 and 6 months posttreatment and quality of life at 6 months posttreatment in this naturalistic study. Further research is warranted to determine the significance and magnitude of the intervention's effects in a randomized controlled trial. BACKGROUND: Fibromyalgia (FM) is a complex chronic pain condition that is difficult to treat. The prevailing approach is an integration of pharmacological, psycho-educational, and behavioral strategies. Information technology offers great potential for FM sufferers to systemically monitor symptoms as well as potential impacts of various management strategies. AIMS: This study aimed to evaluate effects of a web-based, self-monitoring and symptom management system (SMARTLog) that analyzes personal self-monitoring data and delivers data-based feedback over time. MATERIALS AND METHODS: Subjects were self-referred, anonymous, and recruited via publicity on FM advocacy websites. Standardized instruments assessed health status, self-efficacy, and locus of control at baseline and monthly during participation. Subjects were encouraged to complete the SMARTLog several times weekly. Within-subject, univariate, and multivariate analyses were used to derive classification trees for each user associating specific behavior variables with symptom levels over time. RESULTS: Moderate use (3 times weekly x 3 months) increased likelihood of clinically significant improvements in pain, memory, gastrointestinal problems, depression, fatigue, and concentration; heavy use (4.5 times weekly x five months) produced the above plus improvement in stiffness and sleep difficulties. CONCLUSIONS: Individualized, web-based behavioral self-monitoring with personally-tailored feedback can enable FM sufferers to significantly reduce symptom levels over time.
Is Weaver syndrome similar to Sotos?
Overgrowth conditions are a heterogeneous group of disorders characterised by increased growth and variable features, including macrocephaly, distinctive facial appearance and various degrees of learning difficulties and intellectual disability. Among them, Sotos and Weaver syndromes are clinically well defined and due to heterozygous mutations in NSD1 and EZH2, respectively. NSD1 and EZH2 are both histone-modifying enzymes
The syndromes of Sotos and Weaver are paradigmatic of the daily nosologic difficulties faced by clinical geneticists attempting to diagnose and counsel, and to give accurate prognoses in cases of extensive phenotypic overlap between molecularly undefined entities. Vertebrate development is constrained into only very few final or common developmental paths; therefore, no developmental anomaly seen in humans is unique to ("pathognomonic" of) one syndrome. Thus, it is not surprising that prenatal overgrowth occurs in several syndromes, including the Sotos and Weaver syndromes. Are they sufficiently different in other respects to allow the postulation of locus (rather than allele) heterogeneity? Phenotypic data in both conditions are biased because of ascertainment of propositi, and the apparent differences between them may be entirely artificial as they were between the G and BBB syndromes. On the other hand, the Sotos syndrome may be a cancer syndrome, the Weaver syndrome not (though a neuroblastoma was reported in the latter); in the former there is also remarkably advanced dental maturation rarely commented on in the latter. In Weaver syndrome there are more conspicuous contractures and a facial appearance that experts find convincingly different from that of Sotos individuals. Nevertheless, the hypothesis of locus heterogeneity is testable; at the moment we are inclined to favor the hypothesis of allele heterogeneity. An international effort is required to map, isolate, and sequence the causal gene or genes. Sotos syndrome is a childhood overgrowth syndrome characterized by a distinctive facial appearance, height and head circumference >97th percentile, advanced bone age, and developmental delay. Weaver syndrome is characterized by the same criteria but has its own distinctive facial gestalt. Recently, a 2.2-Mb chromosome 5q35 microdeletion, encompassing NSD1, was reported as the major cause of Sotos syndrome, with intragenic NSD1 mutations identified in a minority of cases. We evaluated 75 patients with childhood overgrowth, for intragenic mutations and large deletions of NSD1. The series was phenotypically scored into four groups, prior to the molecular analyses: the phenotype in group 1 (n=37) was typical of Sotos syndrome; the phenotype in group 2 (n=13) was Sotos-like but with some atypical features; patients in group 3 (n=7) had Weaver syndrome, and patients in group 4 (n=18) had an overgrowth condition that was neither Sotos nor Weaver syndrome. We detected three deletions and 32 mutations (13 frameshift, 8 nonsense, 2 splice-site, and 9 missense) that are likely to impair NSD1 functions. The truncating mutations were spread throughout NSD1, but there was evidence of clustering of missense mutations in highly conserved functional domains between exons 13 and 23. There was a strong correlation between presence of an NSD1 alteration and clinical phenotype, in that 28 of 37 (76%) patients in group 1 had NSD1 mutations or deletions, whereas none of the patients in group 4 had abnormalities of NSD1. Three patients with Weaver syndrome had NSD1 mutations, all between amino acids 2142 and 2184. We conclude that intragenic mutations of NSD1 are the major cause of Sotos syndrome and account for some Weaver syndrome cases but rarely occur in other childhood overgrowth phenotypes. Overgrowth syndromes such as Beckwith-Wiedemann syndrome, Sotos syndrome, and Weaver syndrome have an increased risk of neoplasia. Two previous cases of neuroblastoma have been reported in children with Weaver syndrome. We present a third description of a patient with Weaver syndrome and neuroblastoma. In a child with phenotypic characteristics consistent with Weaver syndrome, evaluation for neuroblastoma should be considered. Clinically, Weaver syndrome is closely related to Sotos syndrome, which is frequently caused by mutations in NSD1. This gene also encodes a histone methyltransferase, in this case with activity against histone H3 lysine 36. NSD1 is mutated in carcinoma of the upper aerodigestive tract (www.sanger.ac.uk/genetics/CGP/cosmic/) and also fuses to NUP98 in acute myeloid leukemia. Looking more widely, whole exome screens in lymphoma, multiple myeloma, renal carcinoma and other maligcies have identified genes encoding diverse histone modifiers as targets of somatic mutation. Strikingly, several of these (e.g. MLL2, EP300, CREBBP, ASXL1) are also mutated in human developmental disorders thus pointing towards a remarkable and unexpected convergence between somatic and germline genetics. BACKGROUND: Overgrowth conditions are a heterogeneous group of disorders characterised by increased growth and variable features, including macrocephaly, distinctive facial appearance and various degrees of learning difficulties and intellectual disability. Among them, Sotos and Weaver syndromes are clinically well defined and due to heterozygous mutations in NSD1 and EZH2, respectively. NSD1 and EZH2 are both histone-modifying enzymes. These two epigenetic writers catalyse two specific post-translational modifications of histones: methylation of histone 3 lysine 36 (H3K36) and lysine 27 (H3K27). We postulated that mutations in writers of these two chromatin marks could cause overgrowth conditions, resembling Sotos or Weaver syndromes, in patients with no NSD1 or EZH2 abnormalities. METHODS: We analysed the coding sequences of 14 H3K27 methylation-related genes and eight H3K36 methylation-related genes using a targeted next-generation sequencing approach in three Sotos, 11 'Sotos-like' and two Weaver syndrome patients. RESULTS: We identified two heterozygous mutations in the SETD2 gene in two patients with 'Sotos-like' syndrome: one missense p.Leu1815Trp de novo mutation in a boy and one nonsense p.Gln274* mutation in an adopted girl. SETD2 is non-redundantly responsible for H3K36 trimethylation. The two probands shared similar clinical features, including postnatal overgrowth, macrocephaly, obesity, speech delay and advanced carpal ossification. CONCLUSIONS: Our results illustrate the power of targeted next-generation sequencing to identify rare disease-causing variants. We provide a compelling argument for Sotos and Sotos-like syndromes as epigenetic diseases caused by loss-of-function mutations of epigenetic writers of the H3K36 histone mark.
Which enzyme is targeted by Evolocumab?
Evolocumab (AMG145) is a fully human monoclonal antibody to proprotein convertase subtilisin/kexin type 9 (PCSK9) that demonstrated marked reductions in plasma low-density lipoprotein cholesterol concentrations in statin-intolerant patients.
BACKGROUND: Evolocumab (AMG 145), a monoclonal antibody against proprotein convertase subtilisin/kexin type 9 (PCSK9), significantly reduced low-density lipoprotein cholesterol (LDL-C) in phase 2 studies of 12 weeks' duration. The longer-term efficacy and safety of PCSK9 inhibition remain undefined. METHODS AND RESULTS: Of 1359 randomized and dosed patients in the 4 evolocumab phase 2 parent studies, 1104 (81%) elected to enroll into the Open-Label Study of Long-term Evaluation Against LDL-C (OSLER) study. Regardless of their treatment assignment in the parent study, patients were randomized 2:1 to receive either open-label subcutaneous evolocumab 420 mg every 4 weeks with standard of care (SOC) (evolocumab+SOC, n=736) or SOC alone (n=368). Ninety-two percent of patients in the evolocumab+SOC group and 89% of patients in the SOC group completed 52 weeks of follow-up. Patients who first received evolocumab in OSLER experienced a mean 52.3% [SE, 1.8%] reduction in LDL-C at week 52 (P<0.0001). Patients who received 1 of 6 dosing regimens of evolocumab in the parent studies and received evolocumab+SOC in OSLER had persistent LDL-C reductions (mean reduction, 50.4% [SE, 0.8%] at the end of the parent study versus 52.1% [SE, 1.0%] at 52 weeks; P=0.31). In patients who discontinued evolocumab on entry into OSLER, LDL-C levels returned to near baseline levels. Adverse events and serious adverse events occurred in 81.4% and 7.1% of the evolocumab+SOC group patients and 73.1% and 6.3% of the SOC group patients, respectively. CONCLUSION: Evolocumab dosed every 4 weeks demonstrated continued efficacy and encouraging safety and tolerability over 1 year of treatment in the largest and longest evaluation of a PCSK9 inhibitor in hypercholesterolemic patients to date. CLINICAL TRIAL REGISTRATION URL: http://clinicaltrials.gov. Unique identifier: NCT01439880. Since 2010, mAbs has documented the biopharmaceutical industry's progress in transitioning antibody therapeutics to first Phase 3 clinical studies and regulatory review, and its success at gaining first marketing approvals for antibody-based products. This installment of the "Antibodies to watch" series outlines events anticipated to occur between December 2013 and the end of 2014, including first regulatory actions on marketing applications for vedolizumab, siltuximab, and ramucirumab, as well as the Fc fusion proteins Factor IX-Fc and Factor VIII-Fc; and the submission of first marketing applications for up to five therapeutics (secukinumab, ch14.18, onartuzumab, necitumumab, gevokizumab). Antibody therapeutics in Phase 3 studies are described, with an emphasis on those with study completion dates in 2014, including antibodies targeting interleukin-17a or the interleukin-17a receptor (secukinumab, ixekizumab, brodalumab), proprotein convertase subtilisin/kexin type 9 (alirocumab, evolocumab, bococizumab), and programmed death 1 receptor (lambrolizumab, nivolumab). Five antibodies with US Food and Drug Administration's Breakthrough Therapy designation (obinutuzumab, ofatumumab, lambrolizumab, bimagrumab, daratumumab) are also discussed. AIMS: Prior trials with monoclonal antibodies to proprotein convertase subtilizin/kexin type 9 (PCSK9) reported robust low density lipoprotein cholesterol (LDL-C) reductions. However, the ability to detect potentially beneficial changes in other lipoproteins such as lipoprotein (a), triglycerides, high-density lipoprotein cholesterol (HDL-C), and apolipoprotein (Apo) A1, and adverse events (AEs) was limited by sample sizes of individual trials. We report a pooled analysis from four phase 2 studies of evolocumab (AMG 145), a monoclonal antibody to PCSK9. METHODS AND RESULTS: The trials randomized 1359 patients to various doses of subcutaneous evolocumab every 2 weeks (Q2W) or 4 weeks (Q4W), placebo, or ezetimibe for 12 weeks; 1252 patients contributed to efficacy and 1314, to safety analyses. Mean percentage (95% CI) reductions in LDL-C vs. placebo ranged from 40.2% (44.6%, 35.8%) to 59.3% (63.7%, 54.8%) among the evolocumab groups (all P < 0.001). Statistically significant reductions in apolipoprotein B (Apo B), non-high-density lipoprotein cholesterol (non-HDL-C), triglycerides and lipoprotein (a) [Lp(a)], and increases in HDL-C were also observed. Adverse events (AEs) and serious AEs with evolocumab were reported in 56.8 and 2.0% of patients, compared with 49.2% and 1.2% with placebo. Adjudicated cardiac and cerebrovascular events were reported in 0.3 and 0% in the placebo and 0.9 and 0.3% in the evolocumab arms, respectively. CONCLUSION: In addition to LDL-C reduction, evolocumab, dosed either Q2W or Q4W, demonstrated significant and favourable changes in other atherogenic and anti-atherogenic lipoproteins, and was well tolerated over the 12-week treatment period. INTRODUCTION: Despite the proven efficacy of statins, they are often reported to be inadequate to achieve low-density lipoprotein cholesterol (LDL-C) goals (especially in high-risk patients). Moreover, a large number of subjects cannot tolerate statins or full doses of these drugs. Thus, there is a need for additional effective LDL-C reducing agents. AREAS COVERED: Evolocumab (AMG145) is a monoclonal antibody inhibiting the proprotein convertase subtilisin/kexin type 9 that binds to the liver LDL receptor and prevents it from normal recycling by targeting it for degradation. Phase I and II trials revealed that its subcutaneous injection, either alone or in combination with statins, is able to reduce LDL-C from 40 to 80%, apolipoprotein B100 from 30 to 59% and lipoprotein(a) from 18 to 36% in a dose-dependent manner. The incidence of side effects seems to be low and mainly limited to nasopharyngitis, injection site pain, arthralgia and back pain. EXPERT OPINION: Evolocumab is an innovative powerful lipid-lowering drug, additive to statins and with an apparently large therapeutic range associated to a low rate of mild adverse events. If available data will be confirmed in long-term trials with strong outcomes, Evolocumab will provide an essential tool to treat high-risk patients who need to reach ambitious LDL-C target. BACKGROUND: YUKAWA is a 12-week, randomized, double-blind, placebo-controlled, phase 2 study evaluating the efficacy and safety of evolocumab (AMG 145) in statin-treated Japanese patients at high cardiovascular risk. METHODS AND RESULTS: 310 eligible patients receiving stable statin (±ezetimibe) therapy were randomized to 1 of 6 treatments: placebo every 2 weeks (Q2W) or monthly (QM), evolocumab 70 mg or 140 mg Q2W, or evolocumab 280 mg or 420 mg QM. The primary endpoint was the percentage change from baseline in low-density lipoprotein cholesterol (LDL-C) measured by preparative ultracentrifugation (UC). Secondary endpoints included percentage changes in other lipid parameters and the proportion of patients with LDL-C <1.8 mmol/L. Mean (SD) age was 62 (10) years; 37% were female; and the mean (SD) baseline LDL-C was 3.7 (0.5) mmol/L (by UC). Mean (SE) changes vs. placebo in LDL-C were greatest in the high-dose groups: -68.6 (3.0) % and -63.9 (3.2) % with 140 mg Q2W and 420 mg QM dosing, respectively. Up to 96% of evolocumab-treated patients achieved LDL-C <1.8 mmol/L. Adverse events (AEs) were more frequent in evolocumab (51%) vs. placebo (38%) patients; 4 patients taking evolocumab discontinued treatment because of an AE. There were no significant differences in AE rates based on dose or dose frequency. CONCLUSIONS: In Japanese patients at high cardiovascular risk with hypercholesterolemia on stable statin therapy, evolocumab significantly reduced LDL-C and was well tolerated during this 12-week study. BACKGROUND: Evolocumab, a monoclonal antibody that inhibits proprotein convertase subtilisin/kexin type 9 (PCSK9), significantly reduced low-density lipoprotein (LDL) cholesterol levels in phase 2 studies. We conducted a phase 3 trial to evaluate the safety and efficacy of 52 weeks of treatment with evolocumab. METHODS: We stratified patients with hyperlipidemia according to the risk categories outlined by the Adult Treatment Panel III of the National Cholesterol Education Program. On the basis of this classification, patients were started on background lipid-lowering therapy with diet alone or diet plus atorvastatin at a dose of 10 mg daily, atorvastatin at a dose of 80 mg daily, or atorvastatin at a dose of 80 mg daily plus ezetimibe at a dose of 10 mg daily, for a run-in period of 4 to 12 weeks. Patients with an LDL cholesterol level of 75 mg per deciliter (1.9 mmol per liter) or higher were then randomly assigned in a 2:1 ratio to receive either evolocumab (420 mg) or placebo every 4 weeks. The primary end point was the percent change from baseline in LDL cholesterol, as measured by means of ultracentrifugation, at week 52. RESULTS: Among the 901 patients included in the primary analysis, the overall least-squares mean (±SE) reduction in LDL cholesterol from baseline in the evolocumab group, taking into account the change in the placebo group, was 57.0±2.1% (P<0.001). The mean reduction was 55.7±4.2% among patients who underwent background therapy with diet alone, 61.6±2.6% among those who received 10 mg of atorvastatin, 56.8±5.3% among those who received 80 mg of atorvastatin, and 48.5±5.2% among those who received a combination of 80 mg of atorvastatin and 10 mg of ezetimibe (P<0.001 for all comparisons). Evolocumab treatment also significantly reduced levels of apolipoprotein B, non-high-density lipoprotein cholesterol, lipoprotein(a), and triglycerides. The most common adverse events were nasopharyngitis, upper respiratory tract infection, influenza, and back pain. CONCLUSIONS: At 52 weeks, evolocumab added to diet alone, to low-dose atorvastatin, or to high-dose atorvastatin with or without ezetimibe significantly reduced LDL cholesterol levels in patients with a range of cardiovascular risks. (Funded by Amgen; DESCARTES ClinicalTrials.gov number, NCT01516879.). OBJECTIVES: The aim of this study was to compare biweekly and monthly evolocumab with placebo and oral ezetimibe in patients with hypercholesterolemia in a phase III trial. BACKGROUND: Evolocumab, a fully human monoclonal antibody against proprotein convertase subtilisin/kexin type 9 (PCSK9), significantly reduced LDL-C in phase II trials. METHODS: Patients 18 to 80 years of age with fasting low-density lipoprotein cholesterol (LDL-C) ≥100 and <190 mg/dl and Framingham risk scores ≤10% were randomized (1:1:1:1:2:2) to oral placebo and subcutaneous (SC) placebo biweekly; oral placebo and SC placebo monthly; ezetimibe and SC placebo biweekly; ezetimibe and SC placebo monthly; oral placebo and evolocumab 140 mg biweekly; or oral placebo and evolocumab 420 mg monthly. RESULTS: A total of 614 patients were randomized and administered doses. Evolocumab treatment reduced LDL-C from baseline, on average, by 55% to 57% more than placebo and 38% to 40% more than ezetimibe (p < 0.001 for all comparisons). Evolocumab treatment also favorably altered other lipoprotein levels. Treatment-emergent adverse events (AEs), muscle-related AEs, and laboratory abnormalities were comparable across treatment groups. CONCLUSIONS: In the largest monotherapy trial using a PCSK9 inhibitor to date, evolocumab yielded significant LDL-C reductions compared with placebo or ezetimibe and was well tolerated in patients with hypercholesterolemia. (Monoclonal Antibody Against PCSK9 to Reduce Elevated LDL-C in Subjects Currently Not Receiving Drug Therapy for Easing Lipid Levels-2 [MENDEL-2]; NCT01763827). OBJECTIVES: This study sought to evaluate the efficacy and safety of subcutaneous evolocumab compared with oral ezetimibe in hypercholesterolemic patients who are unable to tolerate effective statin doses. BACKGROUND: Statin intolerance, which is predomitly due to muscle-related side effects, is reported in up to 10% to 20% of patients. Evolocumab, a fully human monoclonal antibody to proprotein convertase subtilisin/kexin type 9 (PCSK9), demonstrated marked reductions in plasma low-density lipoprotein cholesterol (LDL-C) in a phase 2 study in statin-intolerant patients. METHODS: The GAUSS-2 (Goal Achievement after Utilizing an Anti-PCSK9 Antibody in Statin Intolerant Subjects) trial was a 12-week, double-blind study of randomized patients (2:2:1:1) to evolocumab 140 mg every two weeks (Q2W) or evolocumab 420 mg once monthly (QM) both with daily oral placebo or subcutaneous placebo Q2W or QM both with daily oral ezetimibe 10 mg. Co-primary endpoints were percent change from baseline in LDL-C at the mean of weeks 10 and 12, and at week 12. RESULTS: Three hundred seven patients (age 62 ± 10 years; LDL-C 193 ± 59 mg/dl) were randomized. Evolocumab reduced LDL-C from baseline by 53% to 56%, corresponding to treatment differences versus ezetimibe of 37% to 39% (p <0.001). Muscle adverse events occurred in 12% of evolocumab-treated patients and 23% of ezetimibe-treated patients. Treatment-emergent adverse events and laboratory abnormalities were comparable across treatment groups. CONCLUSIONS: Robust efficacy combined with favorable tolerability makes evolocumab a promising therapy for addressing the largely unmet clinical need in high-risk patients with elevated cholesterol who are statin intolerant. (Goal Achievement After Utilizing an Anti-PCSK9 Antibody in Statin Intolerant Subjects-2; NCT01763905). IMPORTANCE: In phase 2 studies, evolocumab, a fully human monoclonal antibody to PCSK9, reduced LDL-C levels in patients receiving statin therapy. OBJECTIVE: To evaluate the efficacy and tolerability of evolocumab when used in combination with a moderate- vs high-intensity statin. DESIGN, SETTING, AND PATIENTS: Phase 3, 12-week, randomized, double-blind, placebo- and ezetimibe-controlled study conducted between January and December of 2013 in patients with primary hypercholesterolemia and mixed dyslipidemia at 198 sites in 17 countries. INTERVENTIONS: Patients (n = 2067) were randomized to 1 of 24 treatment groups in 2 steps. Patients were initially randomized to a daily, moderate-intensity (atorvastatin [10 mg], simvastatin [40 mg], or rosuvastatin [5 mg]) or high-intensity (atorvastatin [80 mg], rosuvastatin [40 mg]) statin. After a 4-week lipid-stabilization period, patients (n = 1899) were randomized to compare evolocumab (140 mg every 2 weeks or 420 mg monthly) with placebo (every 2 weeks or monthly) or ezetimibe (10 mg or placebo daily; atorvastatin patients only) when added to statin therapies. MAIN OUTCOMES AND MEASURES: Percent change from baseline in low-density lipoprotein cholesterol (LDL-C) level at the mean of weeks 10 and 12 and at week 12. RESULTS: Evolocumab reduced LDL-C levels by 66% (95% CI, 58% to 73%) to 75% (95% CI, 65% to 84%) (every 2 weeks) and by 63% (95% CI, 54% to 71%) to 75% (95% CI, 67% to 83%) (monthly) vs placebo at the mean of weeks 10 and 12 in the moderate- and high-intensity statin-treated groups; the LDL-C reductions at week 12 were comparable. For moderate-intensity statin groups, evolocumab every 2 weeks reduced LDL-C from a baseline mean of 115 to 124 mg/dL to an on-treatment mean of 39 to 49 mg/dL; monthly evolocumab reduced LDL-C from a baseline mean of 123 to 126 mg/dL to an on-treatment mean of 43 to 48 mg/dL. For high-intensity statin groups, evolocumab every 2 weeks reduced LDL-C from a baseline mean of 89 to 94 mg/dL to an on-treatment mean of 35 to 38 mg/dL; monthly evolocumab reduced LDL-C from a baseline mean of 89 to 94 mg/dL to an on-treatment mean of 33 to 35 mg/dL. Adverse events were reported in 36%, 40%, and 39% of evolocumab-, ezetimibe-, and placebo-treated patients, respectively. The most common adverse events in evolocumab-treated patients were back pain, arthralgia, headache, muscle spasms, and pain in extremity (all <2%). CONCLUSIONS AND RELEVANCE: In this 12-week trial conducted among patients with primary hypercholesterolemia and mixed dyslipidemia, evolocumab added to moderate- or high-intensity statin therapy resulted in additional LDL-C lowering. Further studies are needed to evaluate the longer-term clinical outcomes and safety of this approach for LDL-C lowering. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT01763866. Proprotein convertase subtilisin/kexin type 9 (PCSK9) is a serine protease that plays an important role in the regulation of serum low-density lipoprotein (LDL) cholesterol by downregulation of LDL receptor, and as such is considered a novel target in cholesterol lowering therapy. In support of the drug development program for Evolocumab, a fully human IgG₂ antibody that targets PCSK9, a quantitative ELISA to measure free PCSK9 in human serum was developed. PCSK9 serves as a biomarker of pharmacological response during treatment, and measuring levels of the free ligand post-dosing was of interest as an aid to establishing the pharmacokinetic and pharmacodynamic properties of the therapeutic. Given the complexities associated with the measurement of free ligand in the presence of high concentrations of circulating drug, it was important to challenge the method with experiments designed to assess ex vivo conditions that have the potential to affect the binding equilibrium of drug and ligand within test samples during routine sampling handling and assay conditions. Herein, we report results of experiments that were conducted to characterize the assay in alignment with regulatory guidance and industry standards, and to establish evidence that the method is measuring the free ligand in circulation at the time serum was collected. A robust supporting data package was generated that demonstrates the method specifically and reproducibly measures the free ligand, and is suitable for its intended use. Statins remain the cornerstone of hypolipidaemic drug treatment. The recent American College of Cardiology (ACC)/American Heart Association (AHA) lipid guidelines suggest using percent reductions of low density lipoprotein cholesterol (LDL-C), according to cardiovascular disease (CVD) risk, rather than specific LDL-C targets. These guidelines raised concerns and other Societies (US, International, European) have not endorsed them. The implementation of previous guidelines in clinical practice is suboptimal due to attitudes of physicians and restrictions in health care systems. Monoclonal antibodies that inhibit proprotein convertase subtilisin/ kexin type 9 (PCSK9), which degrades the LDL receptor, like alirocumab and evolocumab, are in phase 3 trials. These drugs are suitable for statin intolerant or resistant patients, heterozygous familial hypercholesterolaemia (HeFH) and some forms of homozygous FH (HoFH). Mipomersen (antisense oligonucleotide against apolipoprotein B) and lomitapide (microsomal triglyceride transfer protein blocker) have already been approved for HoFH. Eventually, silencing micro-RNA oligonucleotides may also become available. The repair or silencing of genes implicated in hyperlipidaemia and/or atherosclerosis is also on the horizon. If the new therapeutic options mentioned above prove to be effective and safe then by combining them with statins and/or ezetimibe we should be able to effectively control acquired or hereditary dyslipidaemias and substantially further reduce CVD morbidity and mortality. Familial hypercholesterolemia (FH) is a common genetic disorder that presents with robust increases in low-density lipoprotein cholesterol (LDL-C) and can lead to premature cardiovascular disease. There are heterozygous and homozygous forms. The diagnosis is usually made based on blood cholesterol levels, clinical signs and family history. Genetic testing can be used to confirm the diagnosis. Effective lowering of LDL-C in FH can prevent cardiovascular morbidity and mortality, however, the disease remains greatly underdiagnosed. The mainstay of pharmacologic therapy in FH patients is high-dose statins, which are often combined with other lipid-lowering agents. The homozygous form is mainly treated with lipid apheresis. Guideline-recommended target levels of LDL-C are often not reached, making new treatment options desirable. Four classes of newer lipid-lowering drugs offer promising advances in treating FH, namely the apolipoprotein-B synthesis inhibitors (mipomersen), the microsomal transfer protein inhibitors (lomitapide), the cholesterol ester transfer protein inhibitors (anacetrapib, evacetrapib) and the proprotein convertase subtilisin/kexin type 9 inhibitors (evolocumab, alirocumab). In this review, the available evidence regarding the use of these drugs in patients with FH is discussed, with particular focus on their efficacy and safety. INTRODUCTION: To answer the need of a better low-density lipoprotein (LDL) cholesterol control in statin-treated patients at high risk for cardiovascular disease, new injectable lipid-lowering drugs with innovative mechanisms of action are in advanced phase of development or have just been approved. AREAS COVERED: Evolocumab and alirocumab are fully human monoclonal antibodies inhibiting the proprotein convertase subtilisin/kexin type 9 (PCSK9) that binds to hepatic LDL receptor and prevents it from normal recycling by targeting it for degradation. Mipomersen specifically binds to a segment of the human apolipoprotein B100 messenger RNA, blocking the translation of the gene product. Phase II (for evolocumab and alirocumab) and III (for evolocumab) trials show that PCSK9 inhibitors are equally well tolerated, with adverse events mainly limited to mild-to-moderate nasopharyngitis, injection-site pain, arthralgia and back pain. Mipomersen use is mainly associated to hepatosteatosis, increased transaminases (> 3 times the upper limit of normal), mild-to-moderate injection-site reactions and flu-like symptoms. EXPERT OPINION: PCSK9 inhibitors have demonstrated their good safety and tolerability in a large number of subjects with different clinical conditions, including statin-intolerance, enlarging their potential use in a broader range of patients. Further data on long-term mipomersen safety are required. A decade after our discovery of the involvement of proprotein convertase subtilisin/kexin type 9 (PCSK9) in cholesterol metabolism through the identification of the first mutations leading to hypercholesterolemia, PCSK9 has become one of the most promising targets in cholesterol and cardiovascular diseases. This challenging work in the genetics of hypercholesterolemia paved the way for a plethora of studies around the world allowing the characterization of PCSK9, its expression, its impact on reducing the abundance of LDL receptor, and the identification of loss-of-function mutations in hypocholesterolemia. We highlight the different steps of this adventure and review the published clinical trials especially those with the anti-PCSK9 antibodies evolocumab (AMG 145) and alirocumab (SAR236553/REGN727), which are in phase III trials. The promising results in lowering LDL cholesterol levels raise hope that the PCSK9 adventure will lead, after the large and long-term ongoing phase III studies evaluating efficacy and safety, to a new anticholesterol pharmacological class. Dyslipidaemia is a critical risk factor for the development of cardiovascular complications such as ischemic heart disease and stroke. Although statins are effective anti-dyslipidemic drugs, their usage is fraught with issues such as failure of adequate lipid control in 30% of cases and intolerance in select patients. The limited potential of other alternatives such as fibrates, bile acid sequestrants and niacin has spurred the search for novel drug molecules with better efficacy and safety. CETP inhibitors such as evacetrapib and anacetrapib have shown promise in raising HDL besides LDL lowering property. Microsomal triglyceride transfer protein (MTP) inhibitors such as lomitapide and Apo CIII inhibitors such as mipomersen have recently been approved in Familial Hypercholesterolemia but experience in the non-familial setting is pretty much limited. One of the novel anti-dyslipidemic drugs which is greatly anticipated to make a mark in LDL-C control is the PCSK9 inhibitors. Some of the anti-dyslipidemic drugs which work by PCSK9 inhibition include evolocumab, alirocumab and ALN-PCS. Other approaches that are being given due consideration include farnesoid X receptor modulation and Lp-PLA2 inhibition. While it may not be an easy proposition to dismantle statins from their current position as a cholesterol reducing agent and as a drug to reduce coronary and cerebro-vascular atherosclerosis, our improved understanding of the disease and appropriate harnessing of resources using sound and robust technology could make rapid in-roads in our pursuit of the ideal anti-dyslipidemic drug. The serine protease proprotein convertase subtilisin/kexin type 9 (PCSK9) binds to the low-density lipoprotein (LDL) receptor (LDLR) and directs it to lysosomes for intracellular degradation. This results in decreased numbers of LDLR available on the hepatic cell surface to bind LDL particles and remove them from the circulation and therefore to a subsequent increase in circulating LDL-cholesterol (LDL-C) plasma levels. Since 2003, when the role of PCSK9 in LDL-C metabolism was discovered, there have been major efforts to develop efficient and safe methods to inhibit it. Amongst those, monoclonal antibodies against PCSK9 are the furthest in development, with multiple phase 3 trials already published and with cardiovascular endpoint trials currently underway. Two fully human monoclonal antibodies, evolocumab (AMG 145) and alirocumab (REGN727/SAR236553), have been extensively studied in a wide range of subjects, such as those with statin intolerance, as an add-on to statin therapy, as a monotherapy and in patients with familial hypercholesterolemia. PCSK9 antibodies result in a consistent and robust decrease in LDL-C plasma levels ranging from 40% to 70%, either on top of statins or as a monotherapy. If the safety data from the on-going phase 3 trials remain as reassuring as the data available till now, PCSK9 antibodies will offer a novel, powerful therapeutic option to decrease LDL-C plasma levels and, hopefully, cardiovascular risk.
Are ultraconserved elements often transcribed?
Yes. Especially, a large fraction of non-exonic UCEs is transcribed across all developmental stages examined from only one DNA strand.
The identification of ultraconserved noncoding sequences in vertebrates has been associated with developmental regulators and DNA-binding proteins. One of the first of these was identified in the intergenic region between the Dlx-5 and Dlx-6 genes, members of the Dlx/dll homeodomain-containing protein family. In previous experiments, we showed that Sonic hedgehog treatment of forebrain neural explants results in the activation of Dlx-2 and the novel noncoding RNA (ncRNA), Evf-1. In this report, we show that the Dlx-5/6 ultraconserved region is transcribed to generate an alternatively spliced form of Evf-1, the ncRNA Evf-2. Evf-2 specifically cooperates with Dlx-2 to increase the transcriptional activity of the Dlx-5/6 enhancer in a target and homeodomain-specific manner. A stable complex containing the Evf-2 ncRNA and the Dlx-2 protein forms in vivo, suggesting that the Evf-2 ncRNA activates transcriptional activity by directly influencing Dlx-2 activity. These experiments identify a novel mechanism whereby transcription is controlled by the cooperative actions of an ncRNA and a homeodomain protein. The possibility that a subset of vertebrate ultraconserved regions may function at both the DNA and RNA level to control key developmental regulators may explain why ultraconserved sequences exhibit 90% or more conservation even after 450 million years of vertebrate evolution. BACKGROUND: Ultraconserved elements (UCEs) are highly constrained elements of mammalian genomes, whose functional role has not been completely elucidated yet. Previous studies have shown that some of them act as enhancers in mouse, while some others are expressed in both normal and cancer-derived human tissues. Only one UCE element so far was shown to present these two functions concomitantly, as had been observed in other isolated instances of single, non ultraconserved enhancer elements. RESULTS: We used a custom microarray to assess the levels of UCE transcription during mouse development and integrated these data with published microarray and next-generation sequencing datasets as well as with newly produced PCR validation experiments. We show that a large fraction of non-exonic UCEs is transcribed across all developmental stages examined from only one DNA strand. Although the nature of these transcripts remains a mistery, our meta-analysis of RNA-Seq datasets indicates that they are unlikely to be short RNAs and that some of them might encode nuclear transcripts. In the majority of cases this function overlaps with the already established enhancer function of these elements during mouse development. Utilizing several next-generation sequencing datasets, we were further able to show that the level of expression observed in non-exonic UCEs is significantly higher than in random regions of the genome and that this is also seen in other regions which act as enhancers. CONCLUSION: Our data shows that the concurrent presence of enhancer and transcript function in non-exonic UCE elements is more widespread than previously shown. Moreover through our own experiments as well as the use of next-generation sequencing datasets, we were able to show that the RNAs encoded by non-exonic UCEs are likely to be long RNAs transcribed from only one DNA strand. Although expression of non-protein-coding RNA (ncRNA) can be altered in human cancers, their functional relevance is unknown. Ultraconserved regions are noncoding genomic segments that are 100% conserved across humans, mice, and rats. Conservation of gene sequences across species may indicate an essential functional role, and therefore we evaluated the expression of ultraconserved RNAs (ucRNA) in hepatocellular cancer (HCC). The global expression of ucRNAs was analyzed with a custom microarray. Expression was verified in cell lines by real-time PCR or in tissues by in situ hybridization using tissue microarrays. Cellular ucRNA expression was modulated with siRNAs, and the effects on global gene expression and growth of human and murine HCC cells were evaluated. Fifty-six ucRNAs were aberrantly expressed in HepG2 cells compared with nonmaligt hepatocytes. Among these ucRNAs, the greatest change was noted for ultraconserved element 338 (uc.338), which was dramatically increased in human HCC compared with noncancerous adjacent tissues. Although uc.338 is partially located within the poly(rC) binding protein 2 (PCBP2) gene, the transcribed ncRNA encoding uc.338 is expressed independently of PCBP2 and was cloned as a 590-bp RNA gene, termed TUC338. Functional gene annotation analysis indicated predomit effects on genes involved in cell growth. These effects were experimentally demonstrated in both human and murine cells. siRNA to TUC338 decreased both anchorage-dependent and anchorage-independent growth of HCC cells. These studies identify a critical role for TUC338 in regulation of transformed cell growth and of transcribed ultraconserved ncRNA as a unique class of genes involved in the pathobiology of HCC. The relevance of the non-coding genome to human disease has mainly been studied in the context of the widespread disruption of microRNA (miRNA) expression and function that is seen in human cancer. However, we are only beginning to understand the nature and extent of the involvement of non-coding RNAs (ncRNAs) in disease. Other ncRNAs, such as PIWI-interacting RNAs (piRNAs), small nucleolar RNAs (snoRNAs), transcribed ultraconserved regions (T-UCRs) and large intergenic non-coding RNAs (lincRNAs) are emerging as key elements of cellular homeostasis. Along with microRNAs, dysregulation of these ncRNAs is being found to have relevance not only to tumorigenesis, but also to neurological, cardiovascular, developmental and other diseases. There is great interest in therapeutic strategies to counteract these perturbations of ncRNAs. OBJECTIVES: The development of colorectal cancer (CRC) is characterized by multiple genetic alterations. Transcribed ultraconserved regions (T-UCRs) are a subset of 481 sequences longer than 200 bp, which are absolutely conserved between orthologous regions of human, rat and mouse genomes, and are actively transcribed. It has recently been proven in cancer systems that differentially expressed T-UCRs could alter the functional characteristics of maligt cells. Genome-wide profiling revealed that T-UCRs have distinct signatures in human leukemia and carcinoma. METHODS: In our study, we examined the expression levels of uc.43, uc.73, uc.134, uc.230, uc.339, uc.388 and uc.399 in 54 samples of primary colorectal carcinomas and 15 samples of non-tumoral adjacent tissues by real-time PCR. T-UCR expression levels were also correlated with commonly used clinicopathological features of CRC. RESULTS: Expression levels of uc.73 (p = 0.0139) and uc.388 (p = 0.0325) were significantly decreased in CRC tissue, and uc.73 indicated a positive correlation with overall survival (p = 0.0315). The lower expression of uc.388 was associated with the distal location of CRC (p = 0.0183), but no correlation of any evaluated T-UCR with clinical stage, grade and tumor diameter was observed. CONCLUSION: Our preliminary results suggest that uc.73 and uc.388 could be potential diagnostic and prognostic biomarkers in CRC patients. Much effort in cancer research has focused on the tiny part of our genome that codes for mRNA. However, it has recently been recognized that microRNAs also contribute decisively to tumorigenesis. Studies have also shown that epigenetic silencing by CpG island hypermethylation of microRNAs with tumor suppressor activities is a common feature of human cancer. The importance of other classes of non-coding RNAs, such as long intergenic ncRNAs (lincRNAs) and transcribed ultraconserved regions (T-UCRs) as altered elements in neoplasia, is also gaining recognition. Thus, we wondered whether there were other ncRNAs undergoing CpG island hypermethylation-associated inactivation in cancer cells. We focused on the small nucleolar RNAs (snoRNAs), a subset of ncRNA with a wide variety of cellular functions, such as chemical modification of RNA, pre-RNA processing and control of alternative splicing. By data mining snoRNA databases and the scientific literature, we selected 49 snoRNAs that had a CpG island within ≤ 2 Kb or that were processed from a host gene with a 5'-CpG island. Bisulfite genomic sequencing of multiple clones in normal colon mucosa and the colorectal cancer cell line HCT-116 showed that 46 snoRNAs were equally methylated in the two samples: completely unmethylated (n = 26) or fully methylated (n = 20). Most interestingly, the host gene-associated 5'-CpG islands of the snoRNAs SNORD123, U70C and ACA59B were hypermethylated in the cancer cells but not in the corresponding normal tissue. CpG island hypermethylation was associated with the transcriptional silencing of the respective snoRNAs. Results of a DNA methylation microarray platform in a comprehensive collection of normal tissues, cancer cell lines and primary maligcies demonstrated that the observed hypermethylation of snoRNAs was a common feature of various tumor types, particularly in leukemias. Overall, our findings indicate the existence of a new subclass of ncRNAs, snoRNAs, that are targeted by epigenetic inactivation in human cancer. Co-option of cis-regulatory modules has been suggested as a mechanism for the evolution of expression sites during development. However, the extent and mechanisms involved in mobilization of cis-regulatory modules remains elusive. To trace the history of non-coding elements, which may represent candidate ancestral cis-regulatory modules affirmed during chordate evolution, we have searched for conserved elements in tunicate and vertebrate (Olfactores) genomes. We identified, for the first time, 183 non-coding sequences that are highly conserved between the two groups. Our results show that all but one element are conserved in non-syntenic regions between vertebrate and tunicate genomes, while being syntenic among vertebrates. Nevertheless, in all the groups, they are significantly associated with transcription factors showing specific functions fundamental to animal development, such as multicellular organism development and sequence-specific DNA binding. The majority of these regions map onto ultraconserved elements and we demonstrate that they can act as functional enhancers within the organism of origin, as well as in cross-transgenesis experiments, and that they are transcribed in extant species of Olfactores. We refer to the elements as 'Olfactores conserved non-coding elements'. Recent data have linked hypoxia, a classic feature of the tumor microenvironment, to the function of specific microRNAs (miRNAs); however, whether hypoxia affects other types of noncoding transcripts is currently unknown. Starting from a genome-wide expression profiling, we demonstrate for the first time a functional link between oxygen deprivation and the modulation of long noncoding transcripts from ultraconserved regions, termed transcribed-ultraconserved regions (T-UCRs). Interestingly, several hypoxia-upregulated T-UCRs, henceforth named 'hypoxia-induced noncoding ultraconserved transcripts' (HINCUTs), are also overexpressed in clinical samples from colon cancer patients. We show that these T-UCRs are predomitly nuclear and that the hypoxia-inducible factor (HIF) is at least partly responsible for the induction of several members of this group. One specific HINCUT, uc.475 (or HINCUT-1) is part of a retained intron of the host protein-coding gene, O-linked N-acetylglucosamine transferase, which is overexpressed in epithelial cancer types. Consistent with the hypothesis that T-UCRs have important function in tumor formation, HINCUT-1 supports cell proliferation specifically under hypoxic conditions and may be critical for optimal O-GlcNAcylation of proteins when oxygen tension is limiting. Our data gives a first glimpse of a novel functional hypoxic network comprising protein-coding transcripts and noncoding RNAs (ncRNAs) from the T-UCRs category. Long non-coding RNAs (lncRNAs) are transcripts longer than ~200 nucleotides with little or no protein-coding capacity. Growing evidence shows that lncRNAs present important function in development and are associated with many human diseases such as cancers, Alzheimer disease, and heart diseases. Transcribed ultraconserved region (T-UCR) transcripts are a novel class of lncRNAs transcribed from ultraconserved regions (UCRs). UCRs are absolutely conserved (100%) between the orthologous regions of the human, rat, and mouse genomes. The UCRs are frequently located at fragile sites and at genomic regions involved in cancers. Recent data suggest that T-UCRs are altered at the transcriptional level in human tumorigenesis and the aberrant T-UCRs expression profiles can be used to differentiate human cancer types. The profound understanding of T-UCRs can throw new light on the pathogenesis of human cancers.
What is the methyl donor of DNA (cytosine-5)-methyltransferases?
S-adenosyl-L-methionine (AdoMet, SAM) is the methyl donor of DNA (cytosine-5)-methyltransferases. DNA (cytosine-5)-methyltransferases catalyze the transfer of a methyl group from S-adenosyl-L-methionine to the C-5 position of cytosine residues in DNA.
The properties of the methyl-directed DNA (cytosine-5-)-methyltransferase (EC 2.1.1.37) suggest that it is the enzyme that maintains patterns of methylation in the human genome. Proposals for the enzyme's mechanism of action suggest that 5-methyldeoxycytidine is produced from deoxycytidine via a dihydrocytosine intermediate. We have used an oligodeoxynucleotide containing 5-fluorodeoxycytidine as a suicide substrate to capture the enzyme and the dihydrocytosine intermediate. Gel retardation experiments demonstrate the formation of the expected covalent complex between duplex DNA containing 5-fluorodeoxycytidine and the human enzyme. Formation of the complex was dependent upon the presence of the methyl donor S-adenosylmethionine, suggesting that it comprises an enzyme-linked 5-substituted dihydrocytosine moiety in DNA. Dihydrocytosine derivatives are extremely labile toward hydrolytic deamination in aqueous solution. Because C-to-T transition mutations are especially prevalent at CG sites in human DNA, we have used high-performance liquid chromatography to search for thymidine that might be generated by hydrolysis during the methyl transfer reaction. Despite the potential for deamination inherent in the formation of the intermediate, the methyltransferase did not produce detectable amounts of thymidine. The data suggest that the ability of the human methyltransferase to preserve genetic information when copying a methylation pattern (i.e., its fidelity) is comparable to the ability of a mammalian DNA polymerase to preserve genetic information when copying a DNA sequence. Thus the high frequency of C-to-T transitions at CG sites in human DNA does not appear to be due to the normal enzymatic maintece of methylation patterns. In the absence of DNA substrate, the DNA methyltransferase (MTase) M.BspRI can methylate itself using the methyl donor S-adenosyl-L-methionine (AdoMet). The methyl group is transferred to two Cys residues of the MTase. The DNA (cytosine-5)-methyltransferase (m5C-MTase) M.BspRI is able to accept the methyl group from the methyl donor S-adenosyl-L-methionine (AdoMet) in the absence of DNA. Transfer of the methyl group to the enzyme is a slow reaction relative to DNA methylation. Self-methylation is dependent on the native conformation of the enzyme and is inhibited by S-adenosyl-L-homocysteine, DNA and sulfhydryl reagents. Amino acid sequencing of proteolytic peptides obtained from M.BspRI, which had been methylated with [methyl-3H]AdoMet, and thin layer chromatography of the modified amino acid identified two cysteines, Cys156 and Cys181 that bind the methyl group in form of S-methylcysteine. One of the acceptor residues, Cys156 is the highly conserved cysteine which plays the role of the catalytic nucleophile of m5C-MTases. The product of the dcm gene is the only DNA cytosine-C5 methyltransferase of Escherichia coli K-12; it catalyses transfer of a methyl group from S-adenosyl methionine (SAM) to the C-5 position of the inner cytosine residue of the cognate sequence CCA/TGG. Sequence-specific, covalent crosslinking of the enzyme to synthetic oligonucleotides containing 5-fluoro-2'-deoxycytidine is demonstrated. This reaction is abolished if serine replaces the cysteine at residue #177 of the enzyme. These results lend strong support to a catalytic mechanism in which an enzyme sulfhydryl group undergoes Michael addition to the C5-C6 double bond, thus activating position C-5 of the substrate DNA cytosine residue for electrophilic attack by the methyl donor SAM. The enzyme is capable of self-methylation in a DNA-independent reaction requiring SAM and the presence of cysteine at position #177. Deoxycytosine methylase (Dcm) enzyme activity causes mutagenesis in vitro either directly by enzyme-induced deamination of cytosine to uracil in the absence of the methyl donor, S-adenosylmethionine (SAM), or indirectly through spontaneous deamination of [5-methyl]cytosine to thymine. Using a Lac reversion assay, we investigated the contribution of the first mechanism to Dcm mutagenesis in vivo by lowering the levels of SAM. Escherichia coli SAM levels were lowered by reducing SAM synthetase activity via the introduction of a metK84 allele or by hydrolyzing SAM using the bacteriophage T3 SAM hydrolase. The metK84 strains exhibited increased C-to-T mutagenesis. Expression of the T3 SAM hydrolase gene, under the control of the arabinose-inducible P(BAD) promoter, effectively reduced Dcm-mediated genomic DNA methylation. However, increased mutagenesis was not observed until extremely high arabinose concentrations were used, and genome methylation at Dcm sites was negligible. Rotation of a DNA or RNA nucleotide out of the double helix and into a protein pocket ('base flipping') is a mechanistic feature common to some DNA/RNA-binding proteins. Here, we report the structure of HhaI methyltransferase in complex with DNA containing a south-constrained abasic carbocyclic sugar at the target site in the presence of the methyl donor byproduct AdoHcy. Unexpectedly, the locked south pseudosugar appears to be trapped in the middle of the flipping pathway via the DNA major groove, held in place primarily through Van der Waals contacts with a set of invariant amino acids. Molecular dynamics simulations indicate that the structural stabilization observed with the south-constrained pseudosugar will not occur with a north-constrained pseudosugar, which explains its lowered binding affinity. Moreover, comparison of structural transitions of the sugar and phosphodiester backbone observed during computational studies of base flipping in the M.HhaI-DNA-AdoHcy ternary complex indicate that the south-constrained pseudosugar induces a conformation on the phosphodiester backbone that corresponds to that of a discrete intermediate of the base-flipping pathway. As previous crystal structures of M.HhaI ternary complex with DNA displayed the flipped sugar moiety in the antipodal north conformation, we suggest that conversion of the sugar pucker from south to north beyond the middle of the pathway is an essential part of the mechanism through which flipping must proceed to reach its final destination. We also discuss the possibility of the south-constrained pseudosugar mimicking a transition state in the phosphodiester and sugar moieties that occurs during DNA base flipping in the presence of M.HhaI.
Is peripheral neuroepithelioma related to Ewing sarcoma?
Experimental data support the concept that Ewing sarcoma and peripheral neuroepithelioma are both peripheral primitive neuroectodermal neoplasms, differing only in the extent of neuroectodermal phenotype and morphological differentiation.
The histogenesis of Ewing sarcoma, the second most frequent bone tumor in humans, remains controversial. Four Ewing cell lines were analyzed by immunological methods. A panel of antibodies directed to T, B, and myelomonocytic markers gave negative results. Surface antigens recognized on Ewing cells were found to be related to the neuroectoderm lineage. Ganglioside GD2, a marker of neuroectodermal tissues and tumors, was present on all lines. These were also stained by the mouse monoclonal antibody HNK-1, which detects a carbohydrate epitope present on several glycoconjugates of the nervous system, including two glycoproteins, the myelin-associated glycoprotein and the neural cell-adhesion molecule (N-CAM), and an acidic glycolipid of the peripheral nervous system. The P61 monoclonal antibody, which reacts with a peptide moiety of N-CAM, and a rabbit antiserum, raised to purified mouse N-CAM and not recognizing the HNK-1-defined epitope, were also reactive. By contrast, all antibodies specific for hematopoietic cell surface antigens were totally negative. Besides these antigenic features, Ewing sarcoma cells are characterized by a specific t(11;22)(q24;q12) translocation also observed in neuroepithelioma, a neuroectodermal tumor, suggesting a possible evolutionary related origin. The recent finding that the human N-CAM gene is located at the vicinity of the breakpoint on chromosome 11 indicates that it might be involved in genetic rearrangements occurring in this region. Ewing's sarcoma (ES) and peripheral neuroepithelioma (PN) are closely related tumors, and it can be difficult to distinguish them from other small-round-cell tumors (SRCTs). The glycoprotein p30/32MIC2 is highly, but not exclusively, expressed in both ES and PN. Although the monoclonal antibody (Mab) HBA71, which reacts with P30/32MIC2, has been reported to be relatively specific and highly sensitive for both neoplasms, it is not readily available. Yet, Mab O13 is commercially available, and it purportedly displays the same immunostaining characteristics as HBA71. Because O13 has not been studied extensively, we immunostained 21 ES/PNs and 147 other tumors or lesions that might show SRCT-like features with O13. The results were similar to those reported for HBA71. We found O13 to be 100% sensitive for ES/PN; and, no immunostaining was noted on the SRCTs often included in the differential diagnosis of ES/PN (i.e., conventional neuroblastoma, rhabdomyosarcoma, and non-lymphoblastic lymphomas). But, O13 immunoreacted with lymphoblastic lymphomas and some other tumors and normal tissues. Nonetheless, this nonspecific reactivity should not cause diagnostic problems, if an antibody panel containing anti-desmin and anti-leukocyte common antigen is used in conjunction with O13. We conclude that, within the proper diagnostic context, strong immunoreactivity of a SRCT tumor for O13 should be considered good evidence that the tumor is ES/PN. Large group of small-round-cell tumours of soft tissues and bone represents a complex diagnostic problem for the pathologists. Neuronal nature of many tumours from this group is proven by means of new methods--immunophenotypic analysis, tissue culture, cytogenetics. Peripheral neuroepithelioma, Ewing tumour, primitive neuroectodermal tumour (PNET), Askin tumour belong to these neoplasms. These tumours anatomically have no connection with the structures of the central nervous system or autonomous sympathetic nervous system. Ewing's sarcoma of bone (ESB) and peripheral neuroepithelioma (PN) are frequently considered to be different tumors. Some researchers have suggested that PN is morphologically a neuroectodermal Ewing's sarcoma. We sought to determine the extent of neuroectodermal features in conventional ESB on direct patient material (25 cases) and to compare these tumors with a similar group of readily diagnosed PNs (10 cases). Light microscopic, ultrastructural, and immunophenotypic parameters were assessed and compared for both groups. The avidin-biotin complex method was used. All tumors were antigenically intact since all stained for vimentin or at least one marker. Neuroectodermal antigens (neuron-specific enolase, Leu-7 [HNK-1], neurofilament 200 kd, and S100) were found in nine of 10 cases of PN and in 17 of 25 cases of ESB. In ESB, an atypical light microscopic appearance correlated with the presence of neuroectodermal features in most cases, but neuroectodermal phenotype was more frequent (68%) than morphological evidence of neuroectodermal differentiation (36%). These data support the concept that ESB and PN are both peripheral primitive neuroectodermal neoplasms, differing only in extent of neuroectodermal phenotype and morphological differentiation. The eleventh cytogenetically analyzed Askin's tumour, diagnosed in a two-year-old girl, is reported. Chromosomal analysis revealed a pseudodiploid karyotype of tumour cells with translocations of t(11;22)(q24;q12) and der(4)t(2;4)(q24;q35). The observed t(11;22)(q24;q12) is not only a unique characteristic of all cytogenetically analyzed Askin's tumours but it also occurs in 92-100% of peripheral neuroepithelioma and of Ewing's sarcoma, irrespective of its osseous or extraosseous localization. This genetical similarity further supports a nosological concept according to which Askin's tumour, Ewing's sarcoma and peripheral neuroepithelioma represent phenotypic variations of the same tumour, namely the peripheral primitive neuroectodermal tumour. The term "small round-cell tumor" describes a group of highly aggressive maligt tumors composed of relatively small and monotonous undifferentiated cells with high nuclear to cytoplasmic ratios. This group includes Ewing's sarcoma (ES), peripheral neuroepithelioma (aka, primitive neuroectodermal tumor or extraskeletal ES), peripheral neuroblastoma ("classic-type"), rhabdomyosarcoma, desmoplastic small round-cell tumor, lymphoma, leukemia, small-cell osteosarcoma, small-cell carcinoma (either undifferentiated or neuroendocrine), olfactory neuroblastoma, cutaneous neuroendocrine carcinoma (aka, Merkel-cell carcinoma), small-cell melanoma, and mesenchymal chondrosarcoma. Their clinical presentations often overlap, thus making a definitive diagnosis problematic in some cases. Yet, a clear understanding of their clinicopathologic features usually allows for a confident diagnosis, especially if immunohistochemistry is used. The following is a review of the immunohistochemistry of this small round-cell tumor group. Ewing's sarcoma/peripheral primitive neuroectodermal tumors (ES/pPNET) are a group of small round cell sarcomas that show varying degrees of neuroectodermal differentiation characterized by translocation involving the EWS gene. Uterine ES/pPNET is a rare entity. A 29-year-old Chinese female who presented with abdominal swelling and pain was diagnosed with a primary uterine ES/pPNET on the basis of clinicopathologic, immunohistochemical and fluorescence in situ hybridization (FISH) data. She was given a multimodal treatment, including neoadjuvant, 95% cytoreductive, chemotherapy and radiotherapy. The patient is currently alive with persistent disease after 18 months of follow-up. We emphasized the crucial role of molecular techniques in the differential diagnosis of small round cell tumors in this unusual location. Multimodal therapy may improve the outcomes of patients.
Which signaling pathway does sonidegib inhibit?
Sonidegib is a Hedghog signalling pathway inhibitor.
PURPOSE: This phase I trial was undertaken to determine the maximum tolerated dose (MTD), dose-limiting toxicities (DLT), safety, tolerability, pharmacokinetics, pharmacodynamics, and preliminary antitumor activity of the novel smoothened inhibitor sonidegib (LDE225), a potent inhibitor of hedgehog signaling, in patients with advanced solid tumors. EXPERIMENTAL DESIGN: Oral sonidegib was administered to 103 patients with advanced solid tumors, including medulloblastoma and basal cell carcinoma (BCC), at doses ranging from 100 to 3,000 mg daily and 250 to 750 mg twice daily, continuously, with a single-dose pharmacokinetics run-in period. Dose escalations were guided by a Bayesian logistic regression model. Safety, tolerability, efficacy, pharmacokinetics, and biomarkers in skin and tumor biopsies were assessed. RESULTS: The MTDs of sonidegib were 800 mg daily and 250 mg twice daily. The main DLT of reversible grade 3/4 elevated serum creatine kinase (18% of patients) was observed at doses ≥ the MTD in an exposure-dependent manner. Common grade 1/2 adverse events included muscle spasm, myalgia, gastrointestinal toxicities, increased liver enzymes, fatigue, dysgeusia, and alopecia. Sonidegib exposure increased dose proportionally up to 400 mg daily, and displayed nonlinear pharmacokinetics at higher doses. Sonidegib exhibited exposure-dependent reduction in GLI1 mRNA expression. Tumor responses observed in patients with medulloblastoma and BCC were associated with evidence of hedgehog pathway activation. CONCLUSIONS: Sonidegib has an acceptable safety profile in patients with advanced solid tumors and exhibits antitumor activity in advanced BCC and relapsed medulloblastoma, both of which are strongly associated with activated hedgehog pathway, as determined by gene expression. Treatment of myelofibrosis (MF), a BCR-ABL-negative myeloproliferative neoplasm, is challenging. The only current potentially curative option, allogeneic hematopoietic stem cell transplant, is recommended for few patients. The remaining patients are treated with palliative therapies to manage MF-related anemia and splenomegaly. Identification of a mutation in the Janus kinase 2 (JAK2) gene (JAK2 V617F) in more than half of all patients with MF has prompted the discovery and clinical development of inhibitors that target JAK2. Although treatment with JAK2 inhibitors has been shown to improve symptom response and quality of life in patients with MF, these drugs do not alter the underlying disease; therefore, novel therapies are needed. The hedgehog (Hh) signaling pathway has been shown to play a role in normal hematopoiesis and in the tumorigenesis of hematologic maligcies. Moreover, inhibitors of the Hh pathway have been shown to inhibit growth and self-renewal capacity in preclinical models of MF. In a mouse model of MF, combined inhibition of the Hh and JAK pathways reduced JAK2 mutant allele burden, reduced bone marrow fibrosis, and reduced white blood cell and platelet counts. Preliminary clinical data also suggest that inhibition of the Hh pathway, alone or in combination with JAK2 inhibition, may enable disease modification in patients with MF. Future studies, including one combining the Hh pathway inhibitor sonidegib and the JAK2 inhibitor ruxolitinib, are underway in patients with MF and will inform whether this combination approach can lead to true disease modification. PURPOSE: The absorption, distribution, metabolism, and excretion of the hedgehog pathway inhibitor sonidegib (LDE225) were determined in healthy male subjects. METHODS: Six subjects received a single oral dose of 800 mg ¹⁴C-sonidegib (74 kBq, 2.0 µCi) under fasting conditions. Blood, plasma, urine, and fecal samples were collected predose, postdose in-house (days 1-22), and during 24-h visits (weekly, days 29-43; biweekly, days 57-99). Radioactivity was determined in all samples using accelerator mass spectrometry (AMS). Liquid chromatography-tandem mass spectrometry (LC-MS/MS) was used to determine concentrations of sonidegib and its main circulating metabolite in plasma. Metabolite profiles and structures were determined in pooled plasma, urine, and fecal samples using high-performance LC-AMS and LC-MS/MS, respectively. RESULTS: A single dose of ¹⁴C-sonidegib was well tolerated in healthy subjects. Unchanged sonidegib and total radioactivity reached peak concentration in plasma by 2 and 3 h, respectively, and demonstrated similarly long half-lives of 319 and 331 h, respectively. Absorbed sonidegib (estimated 6-7 %) was extensively distributed, and the approximate terminal volume of distribution was 2,500 L. Unchanged sonidegib and a metabolite resulting from amide hydrolysis were the major circulating components (36.4 and 15.4 % of radioactivity area under the curve, respectively). Absorbed sonidegib was eliminated predomitly through oxidative metabolism of the morpholine part and amide hydrolysis. Unabsorbed sonidegib was excreted through the feces. Metabolites in excreta accounted for 4.49 % of the dose (1.20 % in urine, 3.29 % in feces). The recovery of radioactivity in urine and feces was essentially complete (95.3 ± 1.93 % of the dose in five subjects; 56.9 % of the dose in one subject with incomplete feces collection suspected). CONCLUSIONS: Sonidegib exhibited low absorption, was extensively distributed, and was slowly metabolized. Elimination of absorbed sonidegib occurred largely by oxidative and hydrolytic metabolism. BACKGROUND: Oral hedgehog inhibitors (HHIs) have shown significant efficacy in the treatment of basal cell carcinoma (BCC). The evaluation of tumor regression has been performed using clinical photography and radiographic scans. Noninvasive imaging techniques, such as reflectance confocal microscopy (RCM) and high-definition optical coherence tomography (HD-OCT), have been shown to be valuable in detecting BCC in the skin. OBJECTIVE: We monitored HHI-treated BCC using RCM and HD-OCT in vivo and correlated morphologic changes seen on imaging to changes in traditional histopathology. METHODS: Six BCCs in 5 patients receiving HHIs (vismodegib or sonidegib) were examined by RCM and HD-OCT before and during treatment. Characteristic features were compared to histopathologic findings, including immunohistochemical analysis. RESULTS: Characteristic features of BCC in RCM and HD-OCT decreased or disappeared completely during HHI treatment. Half of the clinically complete responding tumors still featured tumor residue. Pseudocystic structures ("empty" tumor nests in imaging) and widespread fibrosis (coarse bright fibers) were new findings and could be confirmed by histopathology. LIMITATIONS: Our study was limited by the number of tumor samples and imaging timepoints. CONCLUSION: Using RCM and HD-OCT, HHI-induced regression of BCC can be visualized noninvasively in the skin. The formation of pseudocysts and fibrosis were characteristic signs of BCC response to HHIs. PURPOSE: Distinct molecular subgroups of medulloblastoma, including hedgehog (Hh) pathway-activated disease, have been reported. We identified and clinically validated a five-gene Hh signature assay that can be used to preselect patients with Hh pathway-activated medulloblastoma. EXPERIMENTAL DESIGN: Gene characteristics of the Hh medulloblastoma subgroup were identified through published bioinformatic analyses. Thirty-two genes shown to be differentially expressed in fresh-frozen and formalin-fixed paraffin-embedded tumor samples and reproducibly analyzed by RT-PCR were measured in matched samples. These data formed the basis for building a multi-gene logistic regression model derived through elastic net methods from which the five-gene Hh signature emerged after multiple iterations. On the basis of signature gene expression levels, the model computed a propensity score to determine Hh activation using a threshold set a priori. The association between Hh activation status and tumor response to the Hh pathway inhibitor sonidegib (LDE225) was analyzed. RESULTS: Five differentially expressed genes in medulloblastoma (GLI1, SPHK1, SHROOM2, PDLIM3, and OTX2) were found to associate with Hh pathway activation status. In an independent validation study, Hh activation status of 25 medulloblastoma samples showed 100% concordance between the five-gene signature and Affymetrix profiling. Further, in medulloblastoma samples from 50 patients treated with sonidegib, all 6 patients who responded were found to have Hh-activated tumors. Three patients with Hh-activated tumors had stable or progressive disease. No patients with Hh-nonactivated tumors responded. CONCLUSIONS: This five-gene Hh signature can robustly identify Hh-activated medulloblastoma and may be used to preselect patients who might benefit from sonidegib treatment. The Hedgehog (Hh) signaling pathway is critical for embryonic development. In adult tissues, Hh signaling is relatively quiescent with the exception of roles in tissue maintece and repair. Aberrant activation of Hh signaling is implicated in multiple aspects of transformation, including the maintece of the cancer stem cell (CSC) phenotype. Preclinical studies indicate that CSCs from many tumor types are sensitive to Hh pathway inhibition and that Hh-targeted therapeutics block many aspects of transformation attributed to CSCs, including drug resistance, relapse, and metastasis. However, to date, Hh inhibitors, specifically those targeting Smoothened [such as vismodegib, BMS-833923, saridegib (IPI-926), sonidegib/erismodegib (LDE225), PF-04449913, LY2940680, LEQ 506, and TAK-441], have demonstrated good efficacy as monotherapy in patients with basal cell carcinoma and medulloblastoma, but have shown limited activity in other tumor types. This lack of success is likely due to many factors, including a lack of patient stratification in early trials, cross-talk between Hh and other oncogenic signaling pathways that can modulate therapeutic response, and a limited knowledge of Hh pathway activation mechanisms in CSCs from most tumor types. Here, we discuss Hh signaling mechanisms in the context of human cancer, particularly in the maintece of the CSC phenotype, and consider new therapeutic strategies that hold the potential to expand considerably the scope and therapeutic efficacy of Hh-directed anticancer therapy. BACKGROUND: Patients with advanced basal cell carcinoma have limited treatment options. Hedgehog pathway signalling is aberrantly activated in around 95% of tumours. We assessed the antitumour activity of sonidegib, a Hedgehog signalling inhibitor, in patients with advanced basal cell carcinoma. METHODS: BOLT is an ongoing multicentre, randomised, double-blind, phase 2 trial. Eligible patients had locally advanced basal cell carcinoma not amenable to curative surgery or radiation or metastatic basal cell carcinoma. Patients were randomised via an automated system in a 1:2 ratio to receive 200 mg or 800 mg oral sonidegib daily, stratified by disease, histological subtype, and geographical region. The primary endpoint was the proportion of patients who achieved an objective response, assessed in the primary efficacy analysis population (patients with fully assessable locally advanced disease and all those with metastatic disease) with data collected up to 6 months after randomisation of the last patient. This trial is registered with ClinicalTrials.gov, number NCT01327053. FINDINGS: Between July 20, 2011, and Jan 10, 2013, we enrolled 230 patients, 79 in the 200 mg sonidegib group, and 151 in the 800 mg sonidegib group. Median follow-up was 13·9 months (IQR 10·1-17·3). In the primary efficacy analysis population, 20 (36%, 95% CI 24-50) of 55 patients receiving 200 mg sonidegib and 39 (34%, 25-43) of 116 receiving 800 mg sonidegib achieved an objective response. In the 200 mg sonidegib group, 18 (43%, 95% CI 28-59) patients who achieved an objective response, as assessed by central review, were noted among the 42 with locally advanced basal cell carcinoma and two (15%, 2-45) among the 13 with metastatic disease. In the 800 mg group, 35 (38%, 95% CI 28-48) of 93 patients with locally advanced disease had an objective response, as assessed by central review, as did four (17%, 5-39) of 23 with metastatic disease. Fewer adverse events leading to dose interruptions or reductions (25 [32%] of 79 patients vs 90 [60%] of 150) or treatment discontinuation (17 [22%] vs 54 [36%]) occurred in patients in the 200 mg group than in the 800 mg group. The most common grade 3-4 adverse events were raised creatine kinase (five [6%] in the 200 mg group vs 19 [13%] in the 800 mg group) and lipase concentration (four [5%] vs eight [5%]). Serious adverse events occurred in 11 (14%) of 79 patients in the 200 mg group and 45 (30%) of 150 patients in the 800 mg group. INTERPRETATION: The benefit-to-risk profile of 200 mg sonidegib might offer a new treatment option for patients with advanced basal cell carcinoma, a population that is difficult to treat. FUNDING: Novartis Pharmaceuticals Corporation.
In which phase of the cell cycle arrest is impaired in Fanconi anemia?
In response to damage induced by DNA cross-linking agents, the S-phase checkpoint is inefficient in Fanconi anemia (FA) cells, leading to accumulation of secondary lesions, such as single- and double-strand breaks and gaps. The prolonged time in G2 phase seen in FA cells therefore exists in order to allow the cells to remove lesions which accumulated during the preceding abnormal S phase.
Fanconi anemia (FA) is a genetic disorder defined by cellular hypersensitivity to DNA cross-linking agents, such as mitomycin C (MMC). MMC causes increased FA cell death, chromosome breakage, and accumulation in the G2 phase of the cell cycle. Recently, Fanconi anemia complementation group C (fac) gene knock-out mice have been developed, and SV40-transformed fibroblasts were established from fac homozygous knock-out (-/-), heterozygous (+/-), and wild-type mice (+/+). MMC sensitivity of these cell lines was assessed by three methods: colony-formation assay in the presence of MMC, chromosome breakage, and cell cycle analysis to detect G2 phase arrest. The fac knock-out fibroblasts (-/-) showed a significantly higher sensitivity to MMC than did fibroblasts from wild-type (+/+) or heterozygous (+/-) mice (three experiments). In addition, we analyzed hematopoietic progenitor colony assays of bone marrow cells from fac knock-out (-/-) and heterozygous (+/-) mice. CFU-E, BFU-E, and CFU-GM colony formation from fac nullizygous mouse progenitors was markedly diminished by MMC when compared to growth of progenitors from heterozygous mice. These results show that fac knock-out mouse cells mimic the behavior of human FA-C patient cells in terms of MMC hypersensitivity. The fac knock-out mouse may be used to model some aspects of human FA and should be useful for understanding the function of the FAC protein. Fanconi anemia (FA) is an inherited cancer-susceptibility disorder, characterized by genomic instability, hypersensitivity to DNA cross-linking agents, and a prolonged G2 phase of the cell cycle. We observed a marked dose-dependent accumulation of FA cells in the G2 compartment after treatment with 4,5',8-trimethylpsoralen (Me(3)Pso) in combination with 365 nm irradiation. Using bivariate DNA distribution methodology, we determined the proportion of replicating and arresting S-phase cells and observed that, whereas normal cells arrested DNA replication in the presence of Me(3)Pso cross-links and monoadducts, FA lymphoblasts failed to arrest DNA synthesis. Taken together, the above data suggest that, in response to damage induced by DNA cross-linking agents, the S-phase checkpoint is inefficient in FA cells. This would lead to accumulation of secondary lesions, such as single- and double-strand breaks and gaps. The prolonged time in G2 phase seen in FA cells therefore exists in order to allow the cells to remove lesions which accumulated during the preceding abnormal S phase. Fanconi anemia (FA) is a human genetic disorder characterized by hypersensitivity to DNA crosslinking agents. Its cellular phenotypes include increased chromosome breakage and a marked cell-cycle delay with 4N DNA content after introduction of interstrand DNA crosslinks (ICL). To further understand the nature of this delay previously described as a G2/M arrest, we introduced ICL specifically during G2 and monitored the cells for passage into mitosis. Our results showed that, even at the highest doses, postreplication ICL produced neither G2/M arrest nor chromosome breakage in FA-A or FA-C cells. This suggests that, similar to wild-type cells, DNA replication is required to trigger both responses. Therefore, the 4N cell DNA content observed in FA cells after ICL treatment also represents incomplete DNA replication and arrest in late S phase. FA fibroblasts from complementation groups A and C were able to recover from the ICL-induced cell-cycle arrest, but took approximately 3 times longer than controls. These results indicate that the FA pathway is required for the efficient resolution of ICL-induced S-phase arrest. The genetic syndrome Fanconi anemia (FA) is characterized by aplastic anemia, cancer predisposition and hypersensitivity to DNA interstrand crosslinks (ICLs). FA proteins (FANCs) are thought to work in pathway(s) essential for dealing with crosslinked DNA. FANCs interact with other proteins involved in both DNA repair and S-phase checkpoint such as BRCA1, ATM and the RAD50/MRE11/NBS1 (RMN) complex. We deciphered the previously undefined pathway(s) leading to the ICLs-induced S-phase checkpoint and the role of FANCs in this process. We found that ICLs activate a branched pathway downstream of the ATR kinase: one branch depending on CHK1 activity and the other on the FANCs-RMN complex. The transient slow-down of DNA synthesis was abolished in cells lacking ATR, whereas CHK1-siRNA-treated cells, NBS1 or FA cells showed partial S-phase arrest. CHK1 RNAi in NBS1 or FA cells abolished the S-phase checkpoint, suggesting that CHK1 and FANCs/NBS1 proteins work on parallel pathways. Furthermore, we found that ICLs trigger ATR-dependent FANCD2 phosphorylation and FANCD2/ATR colocalization. This study demonstrates a novel relationship between the FA pathway(s) and the ATR kinase.
Which DNA sequences are more prone for the formation of R-loops?
R-loops, transcriptionally-induced RNA:DNA hybrids, occurring at repeat tracts (CTG)n, (CAG)n, (CGG)n, (CCG)n and (GAA)n, are associated with diseases including myotonic dystrophy, Huntington's disease, fragile X and Friedreich's ataxia. Physiological R-loop formation at CpG island promoters can contribute to DNA replication origin specification at these regions, the most efficient replication initiation sites in mammalian cells. R-loops may also possess beneficial effects, as their widespread formation has been detected over CpG island promoters in human genes. R-loops are particularly enriched over G-rich terminator elements.
Immunoglobulin H class-switch recombination (CSR) occurs between switch regions and requires transcription and activation-induced cytidine deaminase (AID). Transcription through mammalian switch regions, because of their GC-rich composition, generates stable R-loops, which provide single-stranded DNA substrates for AID. However, we show here that the Xenopus laevis switch region S(mu), which is rich in AT and not prone to form R-loops, can functionally replace a mouse switch region to mediate CSR in vivo. X. laevis S(mu)-mediated CSR occurred mostly in a region of AGCT repeats targeted by the AID-replication protein A complex when transcribed in vitro. We propose that AGCT is a primordial CSR motif that targets AID through a non-R-loop mechanism involving an AID-replication protein A complex. R-loops are structures where an RNA strand is base paired with one DNA strand of a DNA duplex, leaving the displaced DNA strand single-stranded. Stable R-loops exist in vivo at prokaryotic origins of replication, the mitochondrial origin of replication, and mammalian immunoglobulin (Ig) class switch regions in activated B lymphocytes. All of these R-loops arise upon generation of a G-rich RNA strand by an RNA polymerase upon transcription of a C-rich DNA template strand. These R-loops are of significant length. For example, the R-loop at the col E1 origin of replication appears to be about 140 bp. Our own lab has focused on class switch regions, where the R-loops can extend well over a kilobase in length. Here, methods are described for detection and analysis of R-loops in vitro and in vivo. Transcription stimulates the genetic instability of trinucleotide repeat sequences. However, the mechanisms leading to transcription-dependent repeat length variation are unclear. We demonstrate, using biochemical and genetic approaches, that the formation of stable RNA.DNA hybrids enhances the instability of CTG.CAG repeat tracts. In vitro transcribed CG-rich repeating sequences, unlike AT-rich repeats and nonrepeating sequences, form stable, ribonuclease A-resistant structures. These RNA.DNA hybrids are eliminated by ribonuclease H treatment. Mutation in the rnhA1 gene that decreases the activity of ribonuclease HI stimulates the instability of CTG.CAG repeats in E. coli. Importantly, the effect of ribonuclease HI depletion on repeat instability requires active transcription. We also showed that transcription-dependent CTG.CAG repeat instability in human cells is stimulated by siRNA knockdown of RNase H1 and H2. In addition, we used bisulfite modification, which detects single-stranded DNA, to demonstrate that the nontemplate DNA strand at transcribed CTG.CAG repeats remains partially single-stranded in human genomic DNA, thus indicating that it is displaced by an RNA.DNA hybrid. These studies demonstrate that persistent hybrids between the nascent RNA transcript and the template DNA strand at CTG.CAG tracts promote instability of DNA trinucleotide repeats. In this issue of Molecular Cell, Ginno et al. (2012) describe unusual sequence features at promoter CpG islands that can lead to formation of persistent RNA-DNA hybrids (R loops), which are proposed to prevent genomic DNA methylation. Friedreich ataxia (FRDA) and Fragile X syndrome (FXS) are among 40 diseases associated with expansion of repeated sequences (TREDs). Although their molecular pathology is not well understood, formation of repressive chromatin and unusual DNA structures over repeat regions were proposed to play a role. Our study now shows that RNA/DNA hybrids (R-loops) form in patient cells on expanded repeats of endogenous FXN and FMR1 genes, associated with FRDA and FXS. These transcription-dependent R-loops are stable, co-localise with repressive H3K9me2 chromatin mark and impede RNA Polymerase II transcription in patient cells. We investigated the interplay between repressive chromatin marks and R-loops on the FXN gene. We show that decrease in repressive H3K9me2 chromatin mark has no effect on R-loop levels. Importantly, increasing R-loop levels by treatment with DNA topoisomerase inhibitor camptothecin leads to up-regulation of repressive chromatin marks, resulting in FXN transcriptional silencing. This provides a direct molecular link between R-loops and the pathology of TREDs, suggesting that R-loops act as an initial trigger to promote FXN and FMR1 silencing. Thus R-loops represent a common feature of nucleotide expansion disorders and provide a new target for therapeutic interventions. Pif1 family helicases are conserved from bacteria to humans. Here, we report a novel DNA patrolling activity which may underlie Pif1's diverse functions: a Pif1 monomer preferentially anchors itself to a 3'-tailed DNA junction and periodically reel in the 3' tail with a step size of one nucleotide, extruding a loop. This periodic patrolling activity is used to unfold an intramolecular G-quadruplex (G4) structure on every encounter, and is sufficient to unwind RNA-DNA heteroduplex but not duplex DNA. Instead of leaving after G4 unwinding, allowing it to refold, or going beyond to unwind duplex DNA, Pif1 repeatedly unwinds G4 DNA, keeping it unfolded. Pif1-induced unfolding of G4 occurs in three discrete steps, one strand at a time, and is powerful enough to overcome G4-stabilizing drugs. The periodic patrolling activity may keep Pif1 at its site of in vivo action in displacing telomerase, resolving R-loops, and keeping G4 unfolded during replication, recombination and repair.DOI: http://dx.doi.org/10.7554/eLife.02190.001. The uticipated widespread occurrence of stable hybrid DNA/RNA structures (R-loops) in human cells and the increasing evidence of their involvement in several human maligcies have invigorated the research on R-loop biology in recent years. Here we propose that physiological R-loop formation at CpG island promoters can contribute to DNA replication origin specification at these regions, the most efficient replication initiation sites in mammalian cells. Quite likely, this occurs by the strand-displacement reaction activating the formation of G-quadruplex structures that target the origin recognition complex (ORC) in the single-stranded conformation. In agreement with this, we found that R-loops co-localize with the ORC within the same CpG island region in a significant fraction of these efficient replication origins, precisely at the position displaying the highest density of G4 motifs. This scenario builds on the connection between transcription and replication in human cells and suggests that R-loop dysregulation at CpG island promoter-origins might contribute to the phenotype of DNA replication abnormalities and loss of genome integrity detected in cancer cells.
Mutation of which gene is implicated in the familial isolated pituitary adenoma?
Mutation of aryl hydrocarbon receptor interacting protein (AIP) gene was implicated in the familial isolated pituitary adenoma (FIPA) syndrome. About 20% of the families with FIPA harbor inactivating mutation in AIP gene.
CONTEXT: An association between germline aryl hydrocarbon receptor-interacting protein (AIP) gene mutations and pituitary adenomas was recently shown. OBJECTIVE: The objective of the study was to assess the frequency of AIP gene mutations in a large cohort of patients with familial isolated pituitary adenoma (FIPA). DESIGN: This was a multicenter, international, collaborative study. SETTING: The study was conducted in 34 university endocrinology and genetics departments in nine countries. PATIENTS: Affected members from each FIPA family were studied. Relatives of patients with AIP mutations underwent AIP sequence analysis. MAIN OUTCOME MEASURES: Presence/absence and description of AIP gene mutations were the main outcome measures. INTERVENTION: There was no intervention. RESULTS: Seventy-three FIPA families were identified, with 156 patients with pituitary adenomas; the FIPA cohort was evenly divided between families with homogeneous and heterogeneous tumor expression. Eleven FIPA families had 10 germline AIP mutations. Nine mutations, R16H, G47_R54del, Q142X, E174frameshift, Q217X, Q239X, K241E, R271W, and Q285frameshift, have not been described previously. Tumors were significantly larger (P = 0.0005) and diagnosed at a younger age (P = 0.0006) in AIP mutation-positive vs. mutation-negative subjects. Somatotropinomas predominated among FIPA families with AIP mutations, but mixed GH/prolactin-secreting tumors, prolactinomas, and nonsecreting adenomas were also noted. Approximately 85% of the FIPA cohort and 50% of those with familial somatotropinomas were negative for AIP mutations. CONCLUSIONS: AIP mutations, of which nine new mutations have been described here, occur in approximately 15% of FIPA families. Although pituitary tumors occurring in association with AIP mutations are predomitly somatotropinomas, other tumor types are also seen. Further study of the impact of AIP mutations on protein expression and activity is necessary to elucidate their role in pituitary tumorigenesis in FIPA. Pituitary adenomas occur in a familial setting in multiple endocrine neoplasia type 1 (MEN1) and Carney's complex (CNC), which occur due to mutations in the genes MEN1 and PRKAR1A respectively. Isolated familial somatotropinoma (IFS) is also a well-described clinical syndrome related only to patients with acrogigantism. Pituitary adenomas of all types--not limited to IFS--can occur in a familial setting in the absence of MEN1 and CNC; this phenotype is termed familial isolated pituitary adenomas (FIPA). Over the past 7 years, we have described over 90 FIPA kindreds. In FIPA, both homogeneous and heterogeneous pituitary adenoma phenotypes can occur within families; virtually all FIPA kindreds contain at least one prolactinoma or somatotropinoma. FIPA differs from MEN1 in terms of a lower proportion of prolactinomas and more frequent somatotropinomas in the FIPA cohort. Patients with FIPA are significantly younger at diagnosis and have significantly larger pituitary adenomas than matched sporadic pituitary adenoma counterparts. A minority of FIPA families overall (15%) exhibit mutations in the aryl hydrocarbon receptor-interacting protein (AIP) gene; AIP mutations are present in only half of IFS kindreds occurring as part of the FIPA cohort. In families with AIP mutations, pituitary adenomas have a penetrance of over 50%. AIP mutations are extremely rare in patients with sporadic pituitary adenomas. This review deals with pituitary adenomas that occur in a familial setting, describes in detail the clinical, pathological, and genetic features of FIPA, and addresses aspects of the clinical approach to FIPA families with and without AIP mutations. Pituitary adenomas can occur in a familial context, or they can be isolated cases, sometimes due to a predisposing syndrome. In multiple endocrine neoplasia type 1, they often associate with a mutation of the menin gene, a tumor-suppressing gene. A new germinal mutation predisposing to the development of multiple endocrine neoplasias has recently been identified in MENI-negative subjects on the gene CDKN1B encoding for p27(kip1)protein. Carney Complex syndrome--a rare disease--is in more than 60% of the cases linked to the inactivation mutation of a gene located on 17q22-24 that encodes the regulatory subunit 1 of protein kinase A, PRKARIA. Isolated familial pituitary adenomas represent 1.9 to 3.2% of the population of subjects presenting a pituitary adenoma. Low penetrance non-sense mutations, Q14X, IVS3-IG>A and R304X, in 11q12-11q13 region encoding AIP protein, (Aryl hydrocarbon receptor Interacting Protein), have been described by Vierimaa et al, in Finish patients with pituitary adenoma predispositions. Familial pituitary adenoma is a rare syndrome which may present either as isolated lesions, or in association with other endocrine tumors, for example in the frame of multiple endocrine neoplasia (MEN-1) or Carney complex (CNC). The most frequently described forms of familial isolated pituitary adenoma (FIPA) are familial somatotropinomas or prolactinomas. Recently, some cases of familial isolated somatotropinoma have been associated with germline mutations in the aryl hydrocarbon receptor interacting protein (AIP) gene. The present report shows heterogeneous FIPA with 3 subtypes of tumor in 3 individuals of the same family: somatotropinoma in the proband, giant prolactinoma in a brother, and gonadotroph cell macroadenoma in the father. A prospective survey also suggested the occurrence of a silent microadenoma in the proband's sister. Clinical screening was performed in the 3 affected members, the 4th suspected case, and 9 additional, asymptomatic relatives. They had no clinical evidence of associated endocrine lesion suggesting MEN-1 or CNC. Genetic screening for germline mutation of the MEN-1, the gene encoding the protein kinase A (PKA) type 1 alpha regulatory subunit (R1 alpha) (PRKAR1alpha) and AIP gene was negative in 2 affected members. In conclusion, these data suggest that familial pituitary adenomas can occur with a heterogeneous functional pattern that is distinguished from MEN-1 or CNC. The absence of mutation of the recently described AIP gene suggests the implication of other predisposing gene(s). Collaborative, multicentric studies are needed to further define the location of gene(s) involved in heterogeneous FIPA. Familial pituitary adenomas occurr in the classical syndromes of MEN1 and Carney Complex as well as in Familial Isolated Pituitary Adenomas (FIPA), an autosomal domit disease with incomplete penetrance. In some families and also rarely in sporadic tumours germline mutations of a gene located on chromosome 11q13 known as the aryl hydrocarbon receptor interacting protein have been found. This article discusses the AIP mutations in these groups and the different molecular interactions of AIP that may play a role in pituitary tumour formation. Familial isolated pituitary adenoma (FIPA) is an autosomal domit condition with variable genetic background and incomplete penetrance. Germline mutations of the aryl hydrocarbon receptor interacting protein (AIP) gene have been reported in 15-40% of FIPA patients. Limited data are available on the functional consequences of the mutations or regarding the regulation of the AIP gene. We describe a large cohort of FIPA families and characterize missense and silent mutations using minigene constructs, luciferase and beta-galactosidase assays, as well as in silico predictions. Patients with AIP mutations had a lower mean age at diagnosis (23.6+/-11.2 years) than AIP mutation-negative patients (40.4+/-14.5 years). A promoter mutation showed reduced in vitro activity corresponding to lower mRNA expression in patient samples. Stimulation of the protein kinase A-pathway positively regulates the AIP promoter. Silent mutations led to abnormal splicing resulting in truncated protein or reduced AIP expression. A two-hybrid assay of protein-protein interaction of all missense variants showed variable disruption of AIP-phosphodiesterase-4A5 binding. In summary, exonic, promoter, splice-site, and large deletion mutations in AIP are implicated in 31% of families in our FIPA cohort. Functional characterization of AIP changes is important to identify the functional impact of gene sequence variants. The identification of mutations in the Aryl hydrocarbon receptor interacting protein (AIP) gene in a subset of familial isolated pituitary adenoma (FIPA) cases has recently expanded our understanding of the pathophysiology of inherited pituitary adenoma disorders. However, a genetic cause of has not yet been determined in the majority (85%) of FIPA families and half of the families with isolated familial somatotropinoma. Several studies and reviews have assessed the genetic and clinical features of AIP-mutated FIPA patients, which range from a complete lack of symptoms in adult/elderly individuals to large, aggressive early-onset pituitary tumors. In this study, we aimed to briefly revise the data available for the 11q13 locus and other additional loci that have been implicated in genetic susceptibility to FIPA: 2p16-12; 3q28; 4q32.3-4q33; chr 5, 8q12.1, chr 14, 19q13.4 and 21q22.1. These candidate regions may contain unidentified gene(s) that can be potentially disrupted in AIP-negative FIPA families. A better knowledge of these susceptibility loci may disclose modifier genes that are likely to play exacerbating or protective roles in the phenotypic diversity of AIP-mutated families. Familial acromegaly may occur as a component of syndromes of multiple endocrine neoplasia or as isolated familial somatotropinoma (IFS), which is included in the spectrum of familial isolated pituitary adenoma (FIPA). We review the pathogenesis of IFS, from the detection of loss of heterozygosity at chromosome 11q13 and establishment of linkage to this chromosome region to the description of germline mutations in the aryl hydrocarbon receptor-interacting protein (AIP) gene. Approximately 40% of IFS families harbor an AIP mutation. In addition, we summarize the clinical features of IFS families with AIP mutations: The adenomas are diagnosed at a young age and are larger than in IFS patients without AIP mutations or in sporadic somatotropinomas, indicating more aggressive disease. Multiple endocrine neoplasia type 1 (MEN1) and type 2 (MEN2) are major genetic disorders carrying a high risk of endocrine tumor development. The mutated genes were identified in 1993 (MEN2-RET) and 1997 (MEN1), enabling genetic testing and functional studies. Genetic analysis has led to new clinical and therapeutic strategies for MEN1/2 patients, and has improved our understanding of the pathways underlying the development of such tumors, which occur in an autosomal domit manner and with high penetrance. The MEN1 gene encodes menin, a protein involved in many cell functions, such as transcription, genome stability, cell cycling and apoptosis. The MEN1 gene has 10 exons, and its exhaustive analysis in MEN1 patients helps guide their management. MEN2 is related to activating missense mutations in the RET protooncogene, which encodes a tyrosine kinase receptor (TKR). RET activation occurs upon autodimerization induced by the binding of specific ligands belonging to glial cell-derived neurotrophic factor-like family (GFL) proteins, regulated by coreceptors. The position of missense mutations--in the extracellular or intracellular TK domains--influences the aggressiveness of the most frequent maligcy, medullary thyroid carcinoma, establishing a genotype-phenotype correlation. We also briefly describe the genetic basis of three other inherited states predisposing individuals to endocrine tumors, namely Carney's syndrome, hyperparathyroidism type 2 (HRPT2) and familial isolated pituitary adenoma (FIPA), which are related to inactivating mutations in the PRKAR1-alpha, HRPT2 and AIP genes, respectively. Mutations of the aryl hydrocarbon receptor interacting protein (AIP) gene are associated with pituitary adenomas that usually occur as familial isolated pituitary adenomas (FIPA). Detailed pathological and tumor genetic data on AIP mutation-related pituitary adenomas are not sufficient. Non-identical twin females presented as adolescents to the emergency department with severe progressive headache caused by large pituitary macroadenomas require emergency neurosurgery; one patient had incipient pituitary apoplexy. Post-surgically, the patients were found to have silent somatotrope adenomas on pathological examination. Furthermore, the light microscopic, immunohistochemical, and electron microscopic studies demonstrated tumors of virtually identical characteristics. The adenomas were accompanied by multiple areas of pituitary hyperplasia, which stained positively for GH, indicating somatotrope hyperplasia. Genetic analyses of the FIPA kindred revealed a novel E216X mutation of the AIP gene, which was present in both the affected patients and the unaffected father. Molecular analysis of surgical specimens revealed loss of heterozygosity (LOH) in the adenoma but showed that LOH was not present in the hyperplastic pituitary tissue from either patient. AIP immunostaining confirmed normal staining in the hyperplastic tissue and decreased staining in the adenoma in the tumors from both patients. These results demonstrate that patients with AIP germline mutation can present with silent somatotrope pituitary adenomas. The finding of somatotrope hyperplasia unaccompanied by AIP LOH suggests that LOH at the AIP locus might be a late event in a potential progression from hyperplastic to adenomatous tissue. Germline mutations in the aryl hydrocarbon receptor-interacting protein gene (AIP) predispose to young-onset pituitary tumours, most often to GH- or prolactin-secreting adenomas, and most of these patients belong to familial isolated pituitary adenoma families. The molecular pathway initiated by the loss-of-function AIP mutations leading to pituitary tumour formation is unknown. AIP, a co-chaperone of heat-shock protein 90 and various nuclear receptors, belongs to the family of tetratricopeptide repeat (TPR)-containing proteins. It has three antiparallel α-helix motifs (TPR domains) that mediate the interaction of AIP with most of its partners. In this review, we summarise the known interactions of AIP described so far. The identification of AIP partners and the understanding of how AIP interacts with these proteins might help to explain the specific phenotype of the families with heterozygous AIP mutations, to gain deeper insight into the pathological process of pituitary tumour formation and to identify novel drug targets. Familial pituitary adenomas occur in multiple endocrine neoplasia type 1, Carney complex, as well as in familial isolated pituitary adenoma syndrome. Familial isolated pituitary adenoma syndrome is an autosomal domit disease with incomplete penetrance. Pituitary adenomas occur in familial setting but without any other specific tumors. In 20-40% of families with this syndrome, mutations have been identified in the aryl hydrocarbon receptor interacting protein gene while in the rest of the families the causative gene or genes have not been identified. Families carrying aryl hydrocarbon receptor interacting protein gene mutations have a distinct phenotype with younger age at diagnosis and a predomice of somatotroph and lactotroph adenomas. Germline mutations of the aryl hydrocarbon receptor interacting protein gene can be occasionally identified in usually young-onset seemingly sporadic cases. Genetic and clinical testing of relatives of patients with aryl hydrocarbon receptor interacting protein gene mutations can lead to earlier diagnosis and treatment at an earlier stage of the pituitary tumor. BACKGROUND: The paradox of pituitary tumours is that persistent growth is so atypical. By definition, all pituitary microadenomas regain complete trophic stability after an initial period of deregulated growth. Unlike tumours in many other organ systems, concern about significant growth of macroadenoma remts after debulking is minimal. Despite reports of a relatively high prevalence of aneuploidy and clonal skewing in these tumours, prolonged efforts to implicate classical proto-oncogene activation and tumour suppressor mutations have been of limited success. No histological or molecular markers reliably predict behaviour. To date, the number of molecular genetic factors unequivocally linked to pituitary tumours can be counted on the fingers of one hand: (1) GNAS1 activation in acromegaly; (2) the MENIN and p27Kip1 (CDKN1B) mutations associated with multiple endocrine neoplasia type 1; (3) mutations of PRKA1RA with loss of 17q22-24 in Carney complex, and (4) aryl hydrocarbon receptor interacting protein gene mutations in 15% of familial isolated pituitary adenomas and 50% of familial isolated acromegaly. Together, these account for only a small proportion (<5%) of sporadic pituitary macroadenomas. CONCLUSION: In most instances, we still do not know what causes quantitative aberrations in trophic behaviour. Familial isolated pituitary adenoma (FIPA) occurs in families and is unrelated to multiple endocrine neoplasia type 1 and Carney complex. Mutations in AIP account only for 15-25% of FIPA families. CDKN1B mutations cause MEN4 in which affected patients can suffer from pituitary adenomas. With this study, we wanted to assess whether mutations in CDKN1B occur among a large cohort of AIP mutation-negative FIPA kindreds. Eighty-eight AIP mutation-negative FIPA families were studied and 124 affected subjects underwent sequencing of CDKN1B. Functional analysis of putative CDKN1B mutations was performed using in silico and in vitro approaches. Germline CDKN1B analysis revealed two nucleotide changes: c.286A>C (p.K96Q) and c.356T>C (p.I119T). In vitro, the K96Q change decreased p27 affinity for Grb2 but did not segregate with pituitary adenoma in the FIPA kindred. The I119T substitution occurred in a female patient with acromegaly. p27(I119T) shows an abnormal migration pattern by SDS-PAGE. Three variants (p.S56T, p.T142T, and c.605+36C>T) are likely nonpathogenic because In vitro effects were not seen. In conclusion, two patients had germline sequence changes in CDKN1B, which led to functional alterations in the encoded p27 proteins in vitro. Such rare CDKN1B variants may contribute to the development of pituitary adenomas, but their low incidence and lack of clear segregation with affected patients make CDKN1B sequencing unlikely to be of use in routine genetic investigation of FIPA kindreds. However, further characterization of the role of CDKN1B in pituitary tumorigenesis in these and other cases could help clarify the clinicopathological profile of MEN4. Pituitary adenomas represent a group of functionally diverse neoplasms with relatively high prevalence in the general population. Most occur sporadically, but inherited genetic predisposing factors are increasingly recognized. Familial isolated pituitary adenoma is a recently defined clinical entity, and is characterized by hereditary presentation of pituitary adenomas in the absence of clinical and genetic features of syndromic disease such as multiple endocrine neoplasia type 1 and Carney complex. Familial isolated pituitary adenoma is inherited in an autosomal domit manner and accounted for approximately 2-3% of pituitary tumors in some series. Germline mutations in the aryl-hydrocarbon interacting protein gene are identified in around 25% of familial isolated pituitary adenoma kindreds. Pituitary adenomas with mutations of the aryl-hydrocarbon interacting protein gene are predomitly somatotropinomas and prolactinomas, but non-functioning adenomas, Cushing disease, and thyrotropinoma may also occur. These tumors may present as macroadenomas in young patients and are often relatively difficult to control. Furthermore, recent evidence indicates that aryl-hydrocarbon interacting protein gene mutations occur in >10% of patients with sporadic macroadenomas that occur before 30 years of age, and in >20% of children with macroadenomas. Genetic screening for aryl-hydrocarbon interacting protein gene mutations is warranted in selected high-risk patients who may benefit from early recognition and follow-up. Familial isolated pituitary adenoma (FIPA) is an autosomal domit disease, characterized by low penetrance, early-onset disease, more invasive tumor growth, as well as somatotroph and lactotroph adenomas in most cases. It has been indicated that the aryl hydrocarbon receptor interacting protein (AIP) gene is a tumor suppressor gene. Many heterozygous mutations have been discovered in AIP in about 20% of FIPA families. However, the exact molecular mechanism by which its disfunction promotes tumorigenesis of pituitary is unclear. Pituitary adenomas are one of the most frequent intracranial tumors and occur with a prevalence of approximately 1:1000 in the developed world. Pituitary adenomas have a serious disease burden, and their management involves neurosurgery, biological therapies, and radiotherapy. Early diagnosis of pituitary tumors while they are smaller may help increase cure rates. Few genetic predictors of pituitary adenoma development exist. Recent years have seen two separate, complimentary advances in inherited pituitary tumor research. The clinical condition of familial isolated pituitary adenomas (FIPA) has been described, which encompasses the familial occurrence of isolated pituitary adenomas outside of the setting of syndromic conditions like multiple endocrine neoplasia type 1 and Carney complex. FIPA families comprise approximately 2% of pituitary adenomas and represent a clinical entity with homogeneous or heterogeneous pituitary adenoma types occurring within the same kindred. The aryl hydrocarbon receptor interacting protein (AIP) gene has been identified as causing a pituitary adenoma predisposition of variable penetrance that accounts for 20% of FIPA families. Germline AIP mutations have been shown to associate with the occurrence of large pituitary adenomas that occur at a young age, predomitly in children/adolescents and young adults. AIP mutations are usually associated with somatotropinomas, but prolactinomas, nonfunctioning pituitary adenomas, Cushing disease, and other infrequent clinical adenoma types can also occur. Gigantism is a particular feature of AIP mutations and occurs in more than one third of affected somatotropinoma patients. Study of pituitary adenoma patients with AIP mutations has demonstrated that these cases raise clinical challenges to successful treatment. Extensive research on the biology of AIP and new advances in mouse Aip knockout models demonstrate multiple pathways by which AIP may contribute to tumorigenesis. This review assesses the current clinical and therapeutic characteristics of more than 200 FIPA families and addresses research findings among AIP mutation-bearing patients in different populations with pituitary adenomas. CONTEXT: The molecular pathogenesis of primary hyperparathyroidism is still largely unknown. The aryl hydrocarbon receptor interacting protein (AIP) gene has a major role in the pathogenesis of familial isolated pituitary adenoma. OBJECTIVE: We evaluated the involvement of the AIP gene in sporadic parathyroid adenomas. PATIENTS AND DESIGN: We performed direct sequencing and multiplex ligation-dependent probe amplification analyses of the AIP gene in a large series of sporadic parathyroid adenomas. Loss of heterozygosity (LOH) at the AIP locus was studied, and aryl hydrocarbon receptor interacting protein immunostaining was also performed. In addition, alterations in the MEN1 gene were studied. RESULTS: A somatic AIP mutation, substitution of arginine with glutamine at codon 304 (R304Q), was identified in 2 of 132 tumors. The mutation was germline in both cases despite the nonfamilial presentation. Heterozygous AIP large deletions were detected in 29 cases including 1 of the 2 mutated tumors, confirming a biallelic inactivation of the AIP gene. The AIP-mutated tumor with LOH showed decreased AIP immunostaining compared with normal parathyroid. LOH at the MEN1 locus, which often shared LOH at the AIP locus, was found in one third of tumors. Somatic MEN1 mutations were found in the 1 of the 2 AIP-mutated tumors and in 22 parathyroid adenomas. In addition, multiplex ligation-dependent probe amplification analysis revealed 1 large deletion of the MEN1 gene in 1 patient. CONCLUSIONS: The AIP gene is rarely involved in parathyroid adenomas, but the germline nature of the mutations suggests that it might predispose to primary hyperparathyroidism. MEN1 gene alterations occur in a substantial proportion of sporadic parathyroid adenomas. Pituitary adenomas are common tumors of the adenohypophysis which can cause considerable morbidity, due to excessive hormonal secretion or compression and local invasion of surrounding structures. The vast majority of pituitary adenomas occur sporadically. Altered gene expression is commonly detected but somatic mutations, epigenetic changes and abnormal microRNAs have also been described. Occurrence of GNAS mutations at a postzygotic stage lead to McCune-Albright syndrome (MAS), a disease causing endocrine hyperfunction and tumors in several organs, including the pituitary. Familial pituitary adenomas occur as part of a syndrome affecting other organs, such as in MEN1 or Carney complex, or occur with pituitary adenomas only as in familial isolated pituitary adenoma (FIPA). FIPA, an autosomal-domit disease with variable penetrance, is explained in 20% of patients by germline mutations in the tumor suppressor aryl hydrocarbon receptor interacting protein(AIP), while no gene abnormality has been identified to date in the majority of the FIPA families. AIP mutation-positive patients have a characteristic clinical phenotype with usually young- or childhood-onset growth hormone (GH) and/or prolactin (PRL)-secreting adenomas and can be seen in cases with no apparent family history as well. Understanding the tumorigenic process in AIP-positive and AIP-negative FIPA patients could result in better diagnostic and treatment options for both familial and sporadic cases. Aryl hydrocarbon receptor-interacting protein (AIP) is associated with 15-20% of familial isolated pituitary adenomas and 50-80% of cases with AIP mutation exhibit a somatotropinoma. Herein we report clinical characteristics of a large family where AIP R304X variants have been identified. AIP mutation analysis was performed on a large (n = 52) Turkish family across six generations. Sella MRIs of 30 family members were obtained. Basal pituitary hormone levels were evaluated in 13 family members harboring an AIP mutation. Thirteen of 52 family members (25%) were found to have a heterozygous nonsense germline R304X mutation in the AIP gene. Seven of the 13 mutation carriers (53.8%) had current or previous history of pituitary adenoma. Of these 7 mutation carriers, all but one had somatotropinoma/somatolactotropinoma (85.7% of the pituitary adenomas). Of the 6 acromegaly patients with AIP mutation (F/M: 3/3) the mean age at diagnosis of acromegaly was 32 ± 10.3 years while the mean age of symptom onset was 24.8 ± 9.9 years. Three of the six (50%) acromegaly cases with AIP mutation within the family presented with a macroadenoma and none presented with gigantism. Biochemical disease control was achieved in 66.6% (4/6) of the mutation carriers with acromegaly after a mean follow-up period of 18.6 ± 17.6 years. Common phenotypic characteristics of familial pituitary adenoma or somatotropinoma due to AIP mutation vary between families or even between individuals within a family. OBJECTIVE: The aryl hydrocarbon receptor interacting protein gene (AIP) is associated with pituitary adenoma (PA). AIP has not been sequenced in East Asian PA populations, so we performed this study in a Han Chinese cohort. DESIGN: Our study included six familial PA pedigrees comprising 16 patients and 27 unaffected relatives, as well as 216 sporadic PA (SPA) patients and 100 unrelated healthy controls. METHODS: AIP sequencing was carried out on genomic DNA isolated from blood samples. Multiplex ligation-dependent probe amplification and microsatellite marker analyses on DNA from the paired tumor tissues were performed for loss of heterozygosity analysis. RESULTS: We identified three common and four rare single nucleotide polymorphisms (SNPs), one intron insertion, one novel synonymous variant, four novel missense variants, and a reported nonsense mutation in three familial isolated PA (FIPA) cases from the same family. Large genetic deletions were not observed in the germline but were seen in the sporadic tumor DNA from three missense variant carriers. The prevalence of AIP pathogenic variants in PA patients here was low (3.88%), but was higher in somatotropinoma patients (9.30%), especially in young adults (≤30 years) and pediatric (≥18 years) paients (17.24% and 25.00% respectively). All AIP variant patients suffered from macroadenomas. However, the AIP mutation rate in FIPA families was low in this cohort (16.67%, 1/6 families). CONCLUSION: AIP gene mutation may not be frequent in FIPA or SPA from the Han Chinese population. AIP sequencing and long-term follow-up investigations should be performed for young patients with large PAs and their families with PA predisposition. CONTEXT: Germline AIP mutations usually cause young-onset acromegaly with low penetrance in a subset of familial isolated pituitary adenoma families. We describe our experience with a large family with R304* AIP mutation and discuss some of the diagnostic dilemmas and management issues. OBJECTIVE: The aim of the study was to identify and screen mutation carriers in the family. PATIENTS: Forty-three family members participated in the study. SETTING: The study was performed in university hospitals. OUTCOME: We conducted genetic and endocrine screening of family members. RESULTS: We identified 18 carriers of the R304* mutation, three family members with an AIP-variant A299V, and two family members who harbored both changes. One of the two index cases presented with gigantism and pituitary apoplexy, the other presented with young-onset acromegaly, and both had surgery and radiotherapy. After genetic and clinical screening of the family, two R304* carriers were diagnosed with acromegaly. They underwent transsphenoidal surgery after a short period of somatostatin analog treatment. One of these two patients is in remission; the other achieved successful pregcy despite suboptimal control of acromegaly. One of the A299V carrier family members was previously diagnosed with a microprolactinoma; we consider this case to be a phenocopy. Height of the unaffected R304* carrier family members is not different compared to noncarrier relatives. CONCLUSIONS: Families with AIP mutations present particular problems such as the occurrence of large invasive tumors, poor response to medical treatment, difficulties with fertility and management of pregcy, and the finding of AIP sequence variants of unknown significance. Because disease mostly develops at a younger age and penetrance is low, the timing and duration of the follow-up of carriers without overt disease requires further study. The psychological and ficial impact of prolonged clinical screening must be considered. Excellent relationships between the family, endocrinologists, and geneticists are essential, and ideally these families should be managed in centers with specialist expertise. Although the cause of familial isolated pituitary adenoma (FIPA) remains unknown in many cases, germline mutations in the aryl hydrocarbon receptor-interacting protein (AIP) gene were identified in approximately 20 % of families with FIPA. We investigated the AIP gene mutation by a standard sequencing method in 12 members of a Japanese two-generation FIPA family, which includes 3 patients with early-onset acromegaly. Multiplex ligation-dependent probe amplification analysis in a tumor sample was attempted to examine the loss of heterozygosity (LOH) in the locus. The effect of the detected mutation on cell proliferation was investigated. A germline mutation of c.943C > T (p.Q315X) generating an AIP protein with the C-terminal end deleted was found in the FIPA family. Biallelic inactivation of AIP by a combination of the germline mutation and LOH at 11q13 was confirmed in the tumor. The nonsense mutation disrupted the ability to inhibit cell proliferation. We conclude that p.Q315X mutation in the AIP gene is a pathogenic variant and the C-terminal region of AIP plays an important role in the predisposition to pituitary adenomas.
which mutations of troponin C gene have been found to cause hypertrophic cardiomyopathy?
The following mutations of troponin C gene have been found to cause hypertrophic cardiomyopathy: L29Q; A8V; A31S; E134D; c.363dupG; A23Q; D145E and C84Y
We investigated structural and functional aspects of the first mutation in TNNC1, coding for the calcium-binding subunit (cTnC) of cardiac troponin, which was detected in a patient with hypertrophic cardiomyopathy [ Hoffmann B, Schmidt-Traub H, Perrot A, Osterziel KJ & Gessner R (2001) Hum Mut17, 524]. This mutation leads to a leucine-glutamine exchange at position 29 in the nonfunctional calcium-binding site of cTnC. Interestingly, the mutation is located in a putative interaction site for the nonphosphorylated N-terminal arm of cardiac troponin I (cTnI) [ Finley NL, Abbott MB, Abusamhadneh E, Gaponenko V, Dong W, Seabrook G, Howarth JW, Rana M, Solaro RJ, Cheung HC et al. (1999) EJB Lett453, 107-112]. According to peptide array experiments, the nonphosphorylated cTnI arm interacts with cTnC around L29. This interaction is almost abolished by L29Q, as observed upon protein kinase A-dependent phosphorylation of cTnI at serine 22 and serine 23 in wild-type troponin. With CD spectroscopy, minor changes are observed in the backbone of Ca2+-free and Ca2+-saturated cTnC upon the L29Q replacement. A small, but significant, reduction in calcium sensitivity was detected upon measuring the Ca2+-dependent actomyosin subfragment 1 (actoS1)-ATPase activity and the sliding velocity of thin filaments. The maximum actoS1-ATPase activity, but not the maximum sliding velocity, was significantly enhanced. In addition, we performed our investigations at different levels of protein kinase A-dependent phosphorylation of cTnI. The in vitro assays mainly showed that the Ca2+ sensitivity of the actoS1-ATPase activity, and the mean sliding velocity of thin filaments, were no longer affected by protein kinase A-dependent phosphorylation of cTnI owing to the L29Q exchange in cTnC. The findings imply a hindered transduction of the phosphorylation signal from cTnI to cTnC. The cardiac troponin C (cTnC) mutation, L29Q, has been found in a patient with familial hypertrophic cardiomyopathy. We previously showed that L29, together with neighboring residues, Asp2, Val28, and Gly30, plays an important role in determining the Ca(2+) affinity of site II, the regulatory site of mammalian cardiac troponin C (McTnC). Here we report on the Ca(2+) binding characteristics of L29Q McTnC and D2N/V28I/L29Q/G30D McTnC (NIQD) utilizing the Phe(27) --> Trp (F27W) substitution, allowing one to monitor Ca(2+) binding and release. We also studied the effect of these mutants on Ca(2+) activation of force generation in single mouse cardiac myocytes using cTnC replacement, together with sarcomere length (SL) dependence. The Ca(2+)-binding affinity of site II of L29Q McTnC(F27W) and NIQD McTnC(F27W) was approximately 1.3- and approximately 1.9-fold higher, respectively, than that of McTnC(F27W). The Ca(2+) disassociation rate from site II of L29Q McTnC(F27W) and NIQD McTnC(F27W) was not significantly different than that of control (McTnC(F27W)). However, the rate of Ca(2+) binding to site II was higher in L29Q McTnC(F27W) and NIQD McTnC(F27W) relative to control (approximately 1.5-fold and approximately 2.0-fold respectively). The Ca(2+) sensitivity of force generation was significantly higher in myocytes reconstituted with L29Q McTnC (approximately 1.4-fold) and NIQD McTnC (approximately 2-fold) compared with those reconstituted with McTnC. Interestingly, the change in Ca(2+) sensitivity of force generation in response to an SL change (1.9, 2.1, and 2.3 mum) was significantly reduced in myocytes containing L29Q McTnC or NIQD McTnC. These results demonstrate that the L29Q mutation enhances the Ca(2+)-binding characteristics of cTnC and that when incorporated into cardiac myocytes, this mutant alters myocyte contractility. Hypertrophic Cardiomyopathy (HCM) is a common primary cardiac disorder defined by a hypertrophied left ventricle, is one of the main causes of sudden death in young athletes, and has been associated with mutations in most sarcomeric proteins (tropomyosin, troponin T and I, and actin, etc.). Many of these mutations appear to affect the functional properties of cardiac troponin C (cTnC), i.e., by increasing the Ca(2+)-sensitivity of contraction, a hallmark of HCM, yet surprisingly, prior to this report, cTnC had not been classified as a HCM-susceptibility gene. In this study, we show that mutations occurring in the human cTnC (HcTnC) gene (TNNC1) have the same prevalence (~0.4%) as well established HCM-susceptibility genes that encode other sarcomeric proteins. Comprehensive open reading frame/splice site mutation analysis of TNNC1 performed on 1025 unrelated HCM patients enrolled over the last 10 years revealed novel missense mutations in TNNC1: A8V, C84Y, E134D, and D145E. Functional studies with these recombit HcTnC HCM mutations showed increased Ca(2+) sensitivity of force development (A8V, C84Y and D145E) and force recovery (A8V and D145E). These results are consistent with the HCM functional phenotypes seen with other sarcomeric-HCM mutations (E134D showed no changes in these parameters). This is the largest cohort analysis of TNNC1 in HCM that details the discovery of at least three novel HCM-associated mutations and more strongly links TNNC1 to HCM along with functional evidence that supports a central role for its involvement in the disease. This study may help to further define TNNC1 as an HCM-susceptibility gene, a classification that has already been established for the other members of the troponin complex. Recently four new hypertrophic cardiomyopathy mutations in cardiac troponin C (cTnC) (A8V, C84Y, E134D, and D145E) were reported, and their effects on the Ca(2+) sensitivity of force development were evaluated (Landstrom, A. P., Parvatiyar, M. S., Pinto, J. R., Marquardt, M. L., Bos, J. M., Tester, D. J., Ommen, S. R., Potter, J. D., and Ackerman, M. J. (2008) J. Mol. Cell. Cardiol. 45, 281-288). We performed actomyosin ATPase and spectroscopic solution studies to investigate the molecular properties of these mutations. Actomyosin ATPase activity was measured as a function of [Ca(2+)] utilizing reconstituted thin filaments (TFs) with 50% mutant and 50% wild type (WT) and 100% mutant cardiac troponin (cTn) complexes: A8V, C84Y, and D145E increased the Ca(2+) sensitivity with only A8V demonstrating lowered Ca(2+) sensitization at the 50% ratio when compared with 100%; E134D was the same as WT at both ratios. Of these four mutants, only D145E showed increased ATPase activation in the presence of Ca(2+). None of the mutants affected ATPase inhibition or the binding of cTn to the TF measured by co-sedimentation. Only D145E increased the Ca(2+) affinity of site II measured by 2-(4'-(2''-iodoacetamido)phenyl)aminonaphthalene-6-sulfonic acid fluorescence in isolated cTnC or the cTn complex. In the presence of the TF, only A8V was further sensitized to Ca(2+). Circular dichroism measurements in different metal-bound states of the isolated cTnCs showed changes in the secondary structure of A8V, C84Y, and D145E, whereas E134D was the same as WT. PyMol modeling of each cTnC mutant within the cTn complex revealed potential for local changes in the tertiary structure of A8V, C84Y, and D145E. Our results indicate that 1) three of the hypertrophic cardiomyopathy cTnC mutants increased the Ca(2+) sensitivity of the myofilament; 2) the effects of the mutations on the Ca(2+) affinity of isolated cTnC, cTn, and TF are not sufficient to explain the large Ca(2+) sensitivity changes seen in reconstituted and fiber assays; and 3) changes in the secondary structure of the cTnC mutants may contribute to modified protein-protein interactions along the sarcomere lattice disrupting the coupling between the cross-bridge and Ca(2+) binding to cTnC. The role of the C-domain sites of cardiac troponin C in the modulation of the calcium signal remains unclear. In this study, we investigated the effects of hypertrophic cardiomyopathy-linked mutations A8V, E134D, and D145E in cardiac troponin C on the properties of the C-domain sites. The A8V mutation had essentially no effect on the calcium or magnesium binding properties of the C-domain sites, while the mutation E134D moderately decreased calcium and magnesium binding affinities. On the other hand, the D145E mutation affected cooperative interactions between sites III and IV, significantly reducing the calcium binding affinity of both sites. Binding of the anchoring region of cardiac troponin I (corresponding to residues 34-71) to cardiac troponin C with the D145E mutation was not able to recover normal calcium binding to the C-domain. Experiments utilizing the fluorescent hydrophobic probe bis-ANS suggest that the D145E mutation dramatically reduced the extent of calcium-induced hydrophobic exposure by the C-domain. At high nonphysiological calcium concentration, A8V, E134D, and D145E mutations minimally affected the affinity of cardiac troponin C for the regulatory region of cardiac troponin I (corresponding to residues 128-180). In contrast, at lower physiological calcium concentration, the D145E mutation led to an approximately 8-fold decrease in the affinity of cardiac troponin C for the regulatory region of cardiac troponin I. Our results suggest that calcium binding properties of the C-domain sites might be important for the proper regulatory function of cardiac troponin C. PurposeHypertrophic cardiomyopathy is the most common cause of sudden death in young people, including trained athletes, and is caused by mutations in genes encoding proteins of the cardiac sarcomere. Mutations in the Troponin C gene (TNNC1) are a rare genetic cause of hypertrophic cardiomyopathy. We describe a novel type of mutation (c.363dupG) in Troponin C, a rare form of hypertrophic cardiomyopathy. METHODS: A family in which a 19-year-old asymptomatic male died of sudden cardiac death due to hypertrophic cardiomyopathy was genetically studied by sequencing 17 genes associated with hypertrophic cardiomyopathy or its phenocopies. RESULTS: A c.363dupG mutation in Troponin C was identified, and tested across the family. CONCLUSIONS: We report the first frameshift mutation (c.363dupG or p.Gln122AlafsX30) in Troponin C causing hypertrophic cardiomyopathy (and sudden cardiac death) in a 19-year-old male, and have demonstrated that the mutation segregates with hypertrophic cardiomyopathy within the family. The objective of this work was to investigate the effect of hypertrophic cardiomyopathy-linked A8V and E134D mutations in cardiac troponin C (cTnC) on the response of reconstituted thin filaments to calcium upon phosphorylation of cardiac troponin I (cTnI) by protein kinase A. The phosphorylation of cTnI at protein kinase A sites was mimicked by the S22D/S23D double mutation in cTnI. Our results demonstrate that the A8V and E134D mutations had no effect on the extent of calcium desensitization of reconstituted thin filaments induced by cTnI pseudophosphorylation. However, the A8V mutation enhanced the effect of cTnI pseudophosphorylation on the rate of dissociation of calcium from reconstituted thin filaments and on the calcium dependence of actomyosin ATPase. Consequently, while the A8V mutation still led to a slower rate of dissociation of calcium from reconstituted thin filaments upon pseudophosphorylation of cTnI, the ability of the A8V mutation to decrease the rate of calcium dissociation was weakened. In addition, the ability of the A8V mutation to sensitize actomyosin ATPase to calcium was weakened after cTnI was replaced by the phosphorylation mimetic of cTnI. Consistent with the hypothesis that the E134D mutation is benign, it exerted a minor to no effect on the rate of dissociation of calcium from reconstituted thin filaments or on the calcium sensitivity of actomyosin ATPase, regardless of the cTnI phosphorylation status. In conclusion, our study enhances our understanding of how cardiomyopathy-linked cTnC mutations affect the response of reconstituted thin filaments to calcium upon cTnI phosphorylation. Defined as clinically unexplained hypertrophy of the left ventricle, hypertrophic cardiomyopathy (HCM) is traditionally understood as a disease of the cardiac sarcomere. Mutations in TNNC1-encoded cardiac troponin C (cTnC) are a relatively rare cause of HCM. Here, we report clinical and functional characterization of a novel TNNC1 mutation, A31S, identified in a pediatric HCM proband with multiple episodes of ventricular fibrillation and aborted sudden cardiac death. Diagnosed at age 5, the proband is family history-negative for HCM or sudden cardiac death, suggesting a de novo mutation. TnC-extracted cardiac skinned fibers were reconstituted with the cTnC-A31S mutant, which increased Ca(2+) sensitivity with no effect on the maximal contractile force generation. Reconstituted actomyosin ATPase assays with 50% cTnC-A31S:50% cTnC-WT demonstrated Ca(2+) sensitivity that was intermediate between 100% cTnC-A31S and 100% cTnC-WT, whereas the mutant increased the activation of the actomyosin ATPase without affecting the inhibitory qualities of the ATPase. The secondary structure of the cTnC mutant was evaluated by circular dichroism, which did not indicate global changes in structure. Fluorescence studies demonstrated increased Ca(2+) affinity in isolated cTnC, the troponin complex, thin filament, and to a lesser degree, thin filament with myosin subfragment 1. These results suggest that this mutation has a direct effect on the Ca(2+) sensitivity of the myofilament, which may alter Ca(2+) handling and contribute to the arrhythmogenesis observed in the proband. In summary, we report a novel mutation in the TNNC1 gene that is associated with HCM pathogenesis and may predispose to the pathogenesis of a fatal arrhythmogenic subtype of HCM. The Ca(2+) binding properties of the FHC-associated cardiac troponin C (cTnC) mutation L29Q were examined in isolated cTnC, troponin complexes, reconstituted thin filament preparations, and skinned cardiomyocytes. While higher Ca(2+) binding affinity was apparent for the L29Q mutant in isolated cTnC, this phenomenon was not observed in the cTn complex. At the level of the thin filament in the presence of phosphomimetic TnI, L29Q cTnC further reduced the Ca(2+) affinity by 27% in the steady-state measurement and increased the Ca(2+) dissociation rate by 20% in the kinetic studies. Molecular dynamics simulations suggest that L29Q destabilizes the conformation of cNTnC in the presence of phosphomimetic cTnI and potentially modulates the Ca(2+) sensitivity due to the changes of the opening/closing equilibrium of cNTnC. In the skinned cardiomyocyte preparation, L29Q cTnC increased Ca(2+) sensitivity in a highly sarcomere length (SL)-dependent manner. The well-established reduction of Ca(2+) sensitivity by phosphomimetic cTnI was diminished by 68% in the presence of the mutation and it also depressed the SL-dependent increase in myofilament Ca(2+) sensitivity. This might result from its modified interaction with cTnI which altered the feedback effects of cross-bridges on the L29Q cTnC-cTnI-Tm complex. This study demonstrates that the L29Q mutation alters the contractility and the functional effects of the phosphomimetic cTnI in both thin filament and single skinned cardiomyocytes and importantly that this effect is highly sarcomere length dependent.
What is known about the effect of acupuncture in smoking cessation ?
Ear acupressure (EAP) and ear acupuncture have been used for smoking cessation, and some positive results have been reported. Auricular (ear) acupressure has been purported to be beneficial in achieving smoking cessation in some studies, while in others has been deemed insignificant. The combined acupuncture-education group showing the greatest effect from treatment.
BACKGROUND: Tobacco smoking is a major cause of preventable disease and premature death. Physicians should play an active role in the control of smoking by encouraging cessation and helping the smoker to choose the most suitable aid to cessation. AIM: To evaluate a simple, ear acupuncture treatment for the cessation of smoking. METHOD: Randomized, single-blind, placebo-controlled trial of 78 currently smoking volunteers from the general public. Volunteers attended an acupuncture clinic in a general practice setting and were given a single treatment of electroacupuncture using two needles at either an active or a placebo site plus self-retained ear seeds for two weeks. The major outcome measure was biochemically validated total cessation of smoking at six months. RESULTS: A total of 12.5% of the active treatment group compared with 0% of the placebo group ceased smoking at six months (P = 0.055, 95% confidence interval -0.033 to 0.323). CONCLUSION: This simple ear electroacupuncture treatment was significantly more effective in helping volunteers to quit smoking than placebo treatment. A double blind, randomized, placebo-controlled clinical study was conducted to evaluate the efficacy of laser acupuncture treatment in adolescent smokers. Three hundred and thirty adolescent smokers at the Smoking Cessation Clinic of Child Guidance Clinic, Institute of Health, Singapore, were randomly assigned in equal numbers to laser acupuncture treatment and sham acupuncture (control) groups. The proportions of patients with complete smoking cessation after completing treatment for four weeks were 21.9% in the treatment group and 21.4% in the control group. At three months post-treatment, the rates for complete cessation were 24.8% and 26.2%, respectively. Thus, there was no significant difference in the rates of smoking cessation in the treatment and control groups. OBJECTIVES: This study examined the effect of acupuncture alone and in combination with education on smoking cessation and cigarette consumption. METHODS: We prospectively studied 141 adults in a quasi-factorial design using acupuncture, sham acupuncture, and education. RESULTS: All groups showed significant reductions in smoking and posttreatment cigarette consumption, with the combined acupuncture-education group showing the greatest effect from treatment. The trend continued in follow-up; however, significant differences were not maintained. Greater pack-year history (i.e. the number of years smoking multiplied by baseline number of cigarettes smoked per year, divided by 20 cigarettes per pack) negatively correlated with treatment effect. Trend analysis suggested 20 pack-years as the cutoff point for this correlation. CONCLUSIONS: Acupuncture and education, alone and in combination, significantly reduce smoking; however, combined they show a significantly greater effect, as seen in subjects with a greater pack-year history. BACKGROUND: In complementary medicine literature studies on long-term observation of one of its methods are rare. OBJECTIVE: The present study is an evaluation of the smoking behavior of patients treated with ear acupuncture for smoking cessation. Additionally we investigated factors that favor or impede smoking cessation. PATIENTS AND METHODS: 249 patients who had undergone ear acupuncture for smoking cessation between 1985 and 1998 in a practice in Aarau (Switzerland) were asked before the first treatment to fill in a form regarding their smoking behavior and retrospectively in autumn 1998 a questionnaire regarding the success of therapy. Ear acupuncture treatment consisted of 2 consultations at an interval of 10 days. The responder rate was 53.8% (134 questionnaires were returned). Finally the data of 126 persons could be evaluated. RESULTS: The Kaplan Meier analysis of the abstinence time yielded a one-year success rate of 41.1%. Men gave up smoking more easily than women. Start of smoking as well as start of treatment between the age of 20 and 40 years were favorable conditions for smoking cessation. People who had smoked 20 cigarettes or more per day before treatment profited the best. For people who smoked as a way of passing the time or because of tediousness it was easier to stop smoking than for people smoking because of nervousness. People living in a non-smoker household were able to stop smoking significantly easier than persons living in a smoker household. CONCLUSIONS: With a one-year success rate of 41.1% ear acupuncture is a competitive alternative to orthodox medicine withdrawal methods. Acupuncture treatment can be applied and adapted individually, furthermore it is economical and without side effects. The use of alternative medicine for smoking cessation have been increasing steadily in recent years. A series of clinical group studies was performed to clarify the effect, outcome and success rate of an acupuncture treatment for smoking cessation. This study was conducted for four weeks using 238 smoking students at 2 high schools. The subjects were separated into two groups: 159 students were treated with acupuncture on the anti-smoking acupoints of the ear, which is known to be effective for cessation of smoking (case group), and 79 students were treated at other sites of the ear (control group). The acupuncture treatment was alternately administered at each side of the ears on a weekly basis for 4 weeks. The smoking cessation success was only 1 case (0.6%) in the case group and none in the control group after 4 weeks. The change in the taste of tobacco and the intensity of the desire to smoke were not significantly different between the case and control groups, but the case group showed a tendency of reduction in the taste of tobacco and the intensity of the desire to smoke. In addition, the reduction in cigarette consumption was not significant, but the tendency of reduction in the study group was significant. It is believed that the site of auricular acupuncture for smoking cessation is not important. However, there was a significant tendency in terms of the reduction in cigarette consumption, the taste of tobacco and the intensity of the desire to smoke in the case group, indicating that auricular acupuncture in smoking cessation has some effect. OBJECTIVES: This study aimed to develop an Internet-assisted smoking cessation program accompanied with auricular acupressure, and compare the quit rate and self-efficacy of youth smokers receiving auricular acupressure with and without the Internet-assisted smoking cessation program. DESIGN: A Website was constructed on IBM Websphere 5.0 and DB2 database using HTML, Javascript, and JSP. A quasiexperimental research design was adopted. Subjects were assigned nonrandomly to two groups. Group 1 received auricular acupressure plus the Internet-assisted smoking cessation program, whereas group 2 received auricular acupressure only. MEASUREMENTS: The data of demographic factors, serum cotinine, quitting rate, nicotine dependence, and self-efficacy of subjects were collected before and after a 4-week intervention. RESULTS: After intervention, the quit rate was 15.78% in group 1 and 2.56% in group 2. Nicotine dependence was significantly lowered in group 1, but remained unchanged in group 2. The improvement of self-efficacy between groups 1 and 2 was significantly different. CONCLUSIONS: The combination of auricular acupressure and Internet-assisted smoking cessation program was more efficacious than auricular acupressure alone in terms of quit rate. BACKGROUND: Tobacco smoking is responsible for human diseases of the lung, heart, circulatory system and various kinds of cancers, and is a serious public health problem worldwide. Acupuncture has been promoted as a treatment modality for smoking cessation. However, its efficacy still remains controversial. METHODS: We conducted a prospective, randomized, controlled trial using auricular acupuncture for smoking cessation in 131 adults who wanted to stop smoking. Thirteen subjects withdrew from the study and 118 subjects were included in the final analyses (mean age, 53.7 +/- 16.8 years; 100 males, 18 females). The treatment group (n = 59) received auricular acupuncture in Shen Men, Sympathetic, Mouth and Lung points for 8 weeks. The control group (n = 59) received sham acupuncture in non-smoking-cessation-related auricular acupoints (Knee, Elbow, Shoulder and Eye points). The enrolled subjects were then followed monthly for 6 months after stopping the acupuncture treatment. RESULTS: Between both groups before acupuncture treatment, there was no significant difference with regard to gender, mean age, education level, and mean values for the age at which smoking started, smoking duration, daily number of cigarettes smoked and nicotine dependent score. At the end of treatment, cigarette consumption had significantly decreased in both groups, but only the treatment group showed a significant decrease in the nicotine withdrawal symptom score. Smoking cessation rate showed no significant difference between the treatment group (27.1%) and the control group (20.3%) at the end of treatment. There was also no significant difference in the smoking cessation rate between the treatment group (16.6%) and the control group (12.1%) at the end of follow-up. There were no major side effects of auricular acupuncture in both groups. CONCLUSION: Our results showed that auricular acupuncture did not have a better efficacy in smoking cessation compared to sham acupuncture. Combined acupuncture with behavior counseling or with nicotine replacement therapy should be used in further smoking cessation trials to enhance the success rate of smoking cessation. OBJECTIVE: To observe therapeutic effect of acupuncture combined with auricular point sticking and pressing for smoking cessation. METHODS: Body acupoints for acupuncture, Jieyan (two horizontal fingers above styloid process of radius), Shenmen (HT 7), Zhongwan (CV 12), Zusanli (ST 36), Sanyingjiao (SP 6). Main ear acupoints: Kou (mouth), Fei (lung), Shenmen, and adjuvant ear points: Shenshangxian (adrenal gland), Wei (stomach), Xin (heart), Neifenmi (endocrine), Qiguan (trachea), Gan (liver). The treatment was given once daily, 6 sessions constituting one course, and the therapeutic effects were observed after 4 courses. RESULTS: Thirty-six were cured, 12 cases were effective, 5 cases were ineffective. CONCLUSION: Acupuncture combined with auricular point sticking and pressing has reliable therapeutic effect for smoking cessation, but it is needed that the patient cooperates actively and has the will of smoking cessation, so as to avoid re-taking smoking. BACKGROUND: Tobacco smoking is still a worldwide health risk. Current pharmacotherapies have at best, a success rate of no more than 50%. Auricular (ear) acupressure has been purported to be beneficial in achieving smoking cessation in some studies, while in others has been deemed insignificant. We hereby describe the protocol for a three-arm randomised controlled trial to examine the possible benefits of self-administered acupressure for smoking cessation. METHODS: Sixty consenting participants with confirmed habit of tobacco smoking will be recruited and randomized into three arms to receive either auricular acupressure at five true acupoints (NADA protocol), auricular acupressure at five sham points, or no auricular acupressure at all. Participants having auricular acupressure will exert firm pressure to each acupoint bilaterally via the bead in the attached plasters whenever they feel the urge to smoke. The treatment phase will last for six weeks during which all participants will be assessed weekly to review their smoking log, state of abstinence, end-exhalation carbon monoxide levels and possible adverse effects including withdrawal reactions and stress levels. At any time, a successful quit date will be defined with continuous abstinence for the following consecutive 7 days. From then on, participants will be evaluated individually for continuous abstinence rate (CAR), end-exhalation carbon monoxide levels and adverse effects of stress and withdrawal at specified intervals up to 26 weeks. Expectancy of treatment will be assessed with a four-item Borkovec and Nau self-assessment credibility scale during and after intervention. DISCUSSION: We incorporate validated outcome measures of smoking cessation into our randomised controlled trial design with the objectives to evaluate the feasibility and possible benefits of self-administered auricular acupressure as a non-invasive alternative to pharmacotherapy for smoking cessation. TRIAL REGISTRATION: ClinicalTrials.gov: NCT01389622 (registered Jul 7 2011). BACKGROUND: Smoking is the largest preventable cause of death and disease worldwide but smokers often fail to quit due to nicotine withdrawal symptoms. Current available pharmaceutical therapies may assist with smoking cessation but may have side effects. Ear acupressure (EAP) and ear acupuncture have been used for smoking cessation, and some positive results have been reported. The aim of the study is to assess the efficacy and safety of EAP in assisting individuals to quit smoking and/or support them in the management of nicotine withdrawal symptoms. METHODS: This study will be a randomised, single-blind, sham-controlled study conducted at RMIT University in Melbourne, Australia. Adult smokers will be randomly assigned to receive EAP specifically for smoking cessation or nonspecific EAP treatments. After a 2-week run-in, participants will be treated once a week for 8 weeks and followed up for 12 weeks. The primary outcome measures will be 7 day point-prevalence cessation rate by self-report validated by expired carbon monoxide and nicotine withdrawal symptoms measured by the Mood and Physical Symptoms Score questionnaire. Secondary outcomes will be self-reported usage of nicotine replacement therapies, cigarette consumption, body weight change and quality of life. The safety end point will be self-reported adverse events associated with EAP. Intention-to-treat analysis will be applied. DISCUSSION: Findings from this study will determine if this EAP intervention alone can be an effective and safe therapy to assist with smoking cessation and the management of nicotine withdrawal symptoms.
Which post-translational histone modifications are characteristic of constitutive heterochromatin?
H3K9me3 is the major marker of constitutive heterochromatin. Other histone methylation marks usually found in constitutive heterochromatin, are H4K20me3 and H3K79me3. Classical histone modifications associated with heterochromatin include H3K9me2, H3K27me1 and H3K27me2. Histone H3 trimethylation at lysine 36 is associated with constitutive and facultative heterochromatin. H3S10 phosphorylation marks constitutive heterochromatin during interphase in early mouse embryos until the 4-cell stage
Histone methylation was first described more than 35 years ago, but its role has remained enigmatic. Proposed functions range from transcriptional regulation to the higher-order packaging of chromatin in preparation for mitotic condensation. Histone methylation can occur on Arg or Lys residues, with an exquisite site selectivity for Lys methylation at specific positions in the N-termini of histones H3 and H4. Thus, Lys methylation joins acetylation and phosphorylation as a third component of a 'histone code' that modifies the underlying chromatin structure of the genetic information. Notably, in contrast to acetylation and phosphorylation, Lys methylation appears to be a relatively stable histone modification, thereby providing an ideal epigenetic mark for more long-term maintece of chromatin states. The recent discovery of the first histone Lys methyltransferase has allowed the identification of a molecular mechanism in which the specific methylation of histone H3 at Lys9 generates a binding site for heterochromatin-associated proteins. These findings have broad implications for the overall functional organization of chromosome structure at constitutive heterochromatin (e.g. centromeres) and for chromatin-dependent inheritance of gene expression patterns. This review discusses how understanding this methylation system should address some of the long-standing mysteries of heterochromatin. Post-translational modifications of histone amino termini are an important regulatory mechanism that induce transitions in chromatin structure, thereby contributing to epigenetic gene control and the assembly of specialized chromosomal subdomains. Methylation of histone H3 at lysine 9 (H3-Lys9) by site-specific histone methyltransferases (Suv39h HMTases) marks constitutive heterochromatin. Here, we show that H3-Lys9 methylation also occurs in facultative heterochromatin of the inactive X chromosome (Xi) in female mammals. H3-Lys9 methylation is retained through mitosis, indicating that it might provide an epigenetic imprint for the maintece of the inactive state. Disruption of the two mouse Suv39h HMTases abolishes H3-Lys9 methylation of constitutive heterochromatin but not that of the Xi. In addition, HP1 proteins, which normally associate with heterochromatin, do not accumulate with the Xi. These observations suggest the existence of an Suv39h-HP1-independent pathway regulating H3-Lys9 methylation of facultative heterochromatin. In eukaryotes, histone methylation is an epigenetic mechanism associated with a variety of functions related to gene regulation or genomic stability. Recently analyzed H3K9 methyltransferases (HMTases) as SUV39H1, Clr4p, DIM-5, Su(var)3-9 or SUVH2 are responsible for the establishment of histone H3 lysine 9 methylation (H3K9me), which is intimately connected with heterochromatinization. In this review, available data will be evaluated concerning (1) the phylogenetic distribution of H3K9me as heterochromatin-specific histone modification and its evolutionary stability in relation to other epigenetic marks, (2) known families of H3K9 methyltransferases, (3) their responsibility for the formation of constitutive heterochromatin and (4) the evolution of Su(var)3-9-like and SUVH-like H3K9 methyltransferases. Compilation and parsimony analysis reveal that histone H3K9 methylation is, next to histone deacetylation, the evolutionary most stable heterochromatic mark, which is established by at least two subfamilies of specialized heterochromatic HMTases in almost all studied eukaryotes. Centromeres are the fragments of DNA that are responsible for proper chromosome segregation. They consist of centromeric chromatin surrounded by blocks of pericentric heterochromatin, playing an important role in centromere function. In somatic cells, the pericentric domains have a specific pattern of epigenetic modifications of core histones and contain specific pericentric proteins. These features are probably more important for the centromere function than the sequence of the centromeric DNA itself. In somatic cells, the HP1alpha and HP1beta proteins are indispensable for constitutive heterochromatin formation and maintece. We have analyzed the localization of these proteins in the primordial, growing, fully-grown, and maturing mouse oocytes. Additionally, we have analyzed post-translational modifications of histone H3, which can influence HP1alpha and HP1beta association with the heterochromatin. We showed that the regions of constitutive heterochromatin have a distinct pattern of histone H3 acetylation and di-, and trimethylation of its lysine 9. We demonstrated that HP1beta protein was present in pericentric chromatin domains in primordial oocytes, growing (transcriptionally active) oocytes, and in fully-grown oocytes, and was released to the cytoplasm after germinal vesicle breakdown. In contrast, the HP1alpha was never detected in primordial oocytes, was first detected in pericentric heterochromatin in growing oocytes, dissociated from pericentric heterochromatin in fully-grown oocytes, and it was never detected in maturing oocytes. The presence of HP1alpha and HP1beta proteins on the heterochromatin of transcriptionally active oocytes and their absence in transcriptionally silent oocytes suggest that they are necessary for the repression of RNA synthesis in heterochromatin domains of transcribing oocytes. Herpesvirus latency is generally thought to be governed by epigenetic modifications, but the dynamics of viral chromatin at early timepoints of latent infection are poorly understood. Here, we report a comprehensive spatial and temporal analysis of DNA methylation and histone modifications during latent infection with Kaposi Sarcoma-associated herpesvirus (KSHV), the etiologic agent of Kaposi Sarcoma and primary effusion lymphoma (PEL). By use of high resolution tiling microarrays in conjunction with immunoprecipitation of methylated DNA (MeDIP) or modified histones (chromatin IP, ChIP), our study revealed highly distinct landscapes of epigenetic modifications associated with latent KSHV infection in several tumor-derived cell lines as well as de novo infected endothelial cells. We find that KSHV genomes are subject to profound methylation at CpG dinucleotides, leading to the establishment of characteristic global DNA methylation patterns. However, such patterns evolve slowly and thus are unlikely to control early latency. In contrast, we observed that latency-specific histone modification patterns were rapidly established upon a de novo infection. Our analysis furthermore demonstrates that such patterns are not characterized by the absence of activating histone modifications, as H3K9/K14-ac and H3K4-me3 marks were prominently detected at several loci, including the promoter of the lytic cycle transactivator Rta. While these regions were furthermore largely devoid of the constitutive heterochromatin marker H3K9-me3, we observed rapid and widespread deposition of H3K27-me3 across latent KSHV genomes, a bivalent modification which is able to repress transcription in spite of the simultaneous presence of activating marks. Our findings suggest that the modification patterns identified here induce a poised state of repression during viral latency, which can be rapidly reversed once the lytic cycle is induced. X chromosome inactivation (XCI) is the transcriptional silencing of one X in female mammals, balancing expression of X genes between females (XX) and males (XY). In placental mammals non-coding XIST RNA triggers silencing of one X (Xi) and recruits a characteristic suite of epigenetic modifications, including the histone mark H3K27me3. In marsupials, where XIST is missing, H3K27me3 association seems to have different degrees of stability, depending on cell-types and species. However, the complete suite of histone marks associated with the Xi and their stability throughout cell cycle remain a mystery, as does the evolution of an ancient mammal XCI system. Our extensive immunofluorescence analysis (using antibodies against specific histone modifications) in nuclei of mammals distantly related to human and mouse, revealed a general absence from the mammalian Xi territory of transcription machinery and histone modifications associated with active chromatin. Specific repressive modifications associated with XCI in human and mouse were also observed in elephant (a distantly related placental mammal), as was accumulation of XIST RNA. However, in two marsupial species the Xi either lacked these modifications (H4K20me1), or they were restricted to specific windows of the cell cycle (H3K27me3, H3K9me2). Surprisingly, the marsupial Xi was stably enriched for modifications associated with constitutive heterochromatin in all eukaryotes (H4K20me3, H3K9me3). We propose that marsupial XCI is comparable to a system that evolved in the common therian (marsupial and placental) ancestor. Silent chromatin of the early inactive X was exapted from neighbouring constitutive heterochromatin and, in early placental evolution, was augmented by the rise of XIST and the stable recruitment of specific histone modifications now classically associated with XCI. The mammalian genome contains numerous regions known as facultative heterochromatin, which contribute to transcriptional silencing during development and cell differentiation. We have analyzed the pattern of histone modifications associated with facultative heterochromatin within the mouse imprinted Snurf-Snrpn cluster, which is homologous to the human Prader-Willi syndrome genomic region. We show here that the maternally inherited Snurf-Snrpn 3-Mb region, which is silenced by a potent transcription repressive mechanism, is uniformly enriched in histone methylation marks usually found in constitutive heterochromatin, such as H4K20me3, H3K9me3, and H3K79me3. Strikingly, we found that trimethylated histone H3 at lysine 36 (H3K36me3), which was previously identified as a hallmark of actively transcribed regions, is deposited onto the silenced, maternally contributed 3-Mb imprinted region. We show that H3K36me3 deposition within this large heterochromatin domain does not correlate with transcription events, suggesting the existence of an alternative pathway for the deposition of this histone modification. In addition, we demonstrate that H3K36me3 is markedly enriched at the level of pericentromeric heterochromatin in mouse embryonic stem cells and fibroblasts. This result indicates that H3K36me3 is associated with both facultative and constitutive heterochromatin. Our data suggest that H3K36me3 function is not restricted to actively transcribed regions only and may contribute to the composition of heterochromatin, in combination with other histone modifications. Non-coding transcription can trigger histone post-translational modifications forming specialized chromatin. In fission yeast, heterochromatin formation requires RNAi and the histone H3K9 methyltransferase complex CLRC, composed of Clr4, Raf1, Raf2, Cul4, and Rik1. CLRC mediates H3K9 methylation and siRNA production; it also displays E3-ubiquitin ligase activity in vitro. DCAFs act as substrate receptors for E3 ligases and may couple ubiquitination with histone methylation. Here, structural alignment and mutation of signature WDxR motifs in Raf1 indicate that it is a DCAF for CLRC. We demonstrate that Raf1 promotes H3K9 methylation and siRNA amplification via two distinct, separable functions. The association of the DCAF Raf1 with Cul4-Rik1 is critical for H3K9 methylation, but dispensable for processing of centromeric transcripts into siRNAs. Thus the association of a DCAF, Raf1, with its adaptor, Rik1, is required for histone methylation and to allow RNAi to signal to chromatin. Phosphorylation of histone H3 at Ser10 (H3S10P) has been linked to a variety of cellular processes, such as chromosome condensation and gene activation/silencing. Remarkably, in mammalian somatic cells, H3S10P initiates in the pericentromeric heterochromatin during the late G2 phase, and phosphorylation spreads throughout the chromosomes arms in prophase, being maintained until the onset of anaphase when it gets dephosphorylated. Considerable studies have been carried out about H3S10P in different organisms; however, there is little information about this histone modification in mammalian embryos. We hypothesized that this epigenetic modification could also be a marker of pericentromeric heterochromatin in preimplantation embryos. We therefore followed the H3S10P distribution pattern in the G1/S and G2 phases through the entire preimplantation development in in vivo mouse embryos. We paid special attention to its localization relative to another pericentromeric heterochromatin marker, HP1β and performed immunoFISH using specific pericentromeric heterochromatin probes. Our results indicate that H3S10P presents a remarkable distribution pattern in preimplantation mouse embryos until the 4-cell stage and is a better marker of pericentromeric heterochromatin than HP1β. After the 8-cell stage, H3S10P kinetic is more similar to the somatic one, initiating during G2 in chromocenters and disappearing upon telophase. Based on these findings, we believe that H3S10P is a good marker of pericentromeric heterochromatin, especially in the late 1- and 2-cell stages as it labels both parental genomes and that it can be used to further investigate epigenetic regulation and heterochromatin mechanisms in early preimplantation embryos.
GV1001 vaccine targets which enzyme?
GV1001 is a 16-amino-acid vaccine peptide derived from the human telomerase reverse transcriptase sequence. It has been developed as a vaccine against various cancers.
Pancreatic cancer has a very high mortality rate and affects approximately 230,000 individuals worldwide. Gemcitabine has become established as the standard therapy for advanced pancreatic cancer; however, the survival advantage is small. Adjuvant chemotherapy using either 5-fluorouracil or gemcitabine is now established in pancreatic cancer as an alternative therapy. Combinations of gemcitabine with either platin agents or capecitabine may be advantageous. Anti-EGFR and anti-VEGF agents have been unsuccessful but multiple tyrosine kinase inhibitors are under investigation. Of the increasing number of immunological agents, the GV1001 antitelomerase vaccine holds some interest. Targeted agents against important mitogenic pathways, including MEK/ERK, Src, PI3K/Akt, mTOR, Hedgehog and NF-kappaB, as well as agents targeting histone deacetylase, poly(ADP-ribose) polymerase, heat shock protein 90 and other agents such as beta-lapachone, hold considerable interest for further development. However, the probability of individual success is low. BACKGROUND: There is currently no curative therapy for cutaneous T cell lymphoma (CTCL). New therapies are therefore needed. Telomerase, the enzyme that allows for unrestricted cell divisions of cancer cells, is a promising target for cancer therapy. The telomerase-specific peptide vaccination GV1001 has shown promising results in previous studies. Since telomerase is expressed in maligt cells of CTCL, GV1001 vaccination in CTCL is a promising new therapeutic approach. OBJECTIVE: We sought to investigate the efficacy of GV1001 vaccination in CTCL patients and characterize the induced immune response. METHODS: Six CTCL patients were vaccinated with the GV-peptide using granulocyte/macrophage colony-stimulating factor as adjuvant. Objective clinical response and the T cell response were assessed. RESULTS: None of the patients demonstrated objective clinical response to the vaccination whereas one patient showed disease progression. 1/6 patients acquired a GV1001-specifc T cell response with a Th1 cytokine profile and expression of skin-homing receptors. This hTERT-specific T cell response was not associated with beneficial modulation of the tumor-infiltrating leukocytes. Furthermore, removal of regulatory T cells did not enhance responsiveness to GV1001 in vitro in any of the patients analyzed. CONCLUSIONS: Our results suggest that the GV1001 vaccination is not effective in CTCL patients and disease progression in 1/6 patients raises concerns about its safety. By analyzing skin-homing properties of GV1001-specific T cells and the involvement of regulatory T cells we nevertheless provide insight into vaccine-induced immune responses which may help to improve vaccine strategies in CTCL. PURPOSE: The study is a proof-of-principle trial evaluating toxicity, immune response, and clinical response in melanoma patients after combined therapy with temozolomide and the telomerase peptide vaccine GV1001. Our previous GV1001 trials showed immune responses in approximately 60% of lung or pancreatic cancer patients. EXPERIMENTAL DESIGN: Twenty-five subjects with advanced stage IV melanoma (M1B or M1C) received concomitant temozolomide and GV1001. Temozolomide was administered 200 mg/m² orally for 5 days every fourth week, and GV1001 as eight injections over 11 weeks. Immune response was evaluated by delayed type hypersensitivity, T-cell proliferation, and cytokine assays. The immunologic responders continued monthly vaccination. RESULTS: The treatment was well tolerated. A GV1001-specific immune response was shown in 18 of 23 evaluated subjects (78%). Patients developing long-term T-cell memory survived more than those rapidly losing their responses. The immune response exhibited several characteristics of possible clinical significance including high IFNγ/IL-10 ratios, polyfunctional cytokine profiles, and recognition of naturally processed antigens. Survival compared favorably with matched controls from a benchmark meta-analysis (1 year: 44% vs. 24%, 2 years: 16% vs. 6.6%). The clinical responses developed gradually over years, contrary to what is expected from chemotherapy. Five patients developed partial tumor regression and six more recorded stable disease. One patient has no remaining disease on fluorodeoxyglucose positron emission tomography scans after 5 years. CONCLUSIONS: The immunologic response rate is considerable compared with previous GV1001 trials without concomitant chemotherapy, although low toxicity is retained. The results warrant further studies of GV1001/temozolomide treatment and support the general concept of combining cancer vaccination with chemotherapy. Telomeres are protective caps at the ends of human chromosomes. Telomeres shorten with each successive cell division in normal human cells whereas, in tumors, they are continuously elongated by human telomerase reverse transcriptase (hTERT). Telomerase is overexpressed in 80-95% of cancers and is present in very low levels or is almost undetectable in normal cells. Because telomerase plays a pivotal role in cancer cell growth it may serve as an ideal target for anticancer therapeutics. Inhibition of telomerase may lead to a decrease of telomere length resulting in cell senescence and apoptosis in telomerase positive tumors. Several strategies of telomerase inhibition are reviewed, including small molecule inhibitors, antisense oligonucleotides, immunotherapies and gene therapies, targeting the hTERT or the ribonucleoprotein subunit hTER. G-quadruplex stabilizers, tankyrase and HSP90 inhibitors targeting telomere and telomerase assembly, and T-oligo approach are also covered. Based on this review, the most promising current telomerase targeting therapeutics are the antisense oligonucleotide inhibitor GRN163L and immunotherapies that use dendritic cells (GRVAC1), hTERT peptide (GV1001) or cryptic peptides (Vx-001). Most of these agents have entered phase I and II clinical trials in patients with various tumors, and have shown good response rates as evidenced by a reduction in tumor cell growth, increased overall disease survival, disease stabilization in advanced staged tumors and complete/partial responses. Most therapeutics have shown to be more effective when used in combination with standard therapies, resulting in concomitant telomere shortening and tumor mass shrinkage, as well as preventing tumor relapse and resistance to single agent therapy. A reverse-transcriptase-subunit of telomerase (hTERT) derived peptide, GV1001, has been developed as a vaccine against various cancers. Previously, we have shown that GV1001 interacts with heat shock proteins (HSPs) and penetrates cell membranes to be localized in the cytoplasm. In this study, we have found that GV1001 lowered the level of intracellular and surface HSPs of various cancer cells. In hypoxic conditions, GV1001 treatment of cancer cells resulted in decreases of HSP90, HSP70, and HIF-1α. Subsequently, proliferation of cancer cells and synthesis of VEGF were significantly reduced by treatment using GV1001 in hypoxic conditions. In an experiment using a nude mouse xenograft model, GV1001 exerted a similar tumor suppressive effect, further confirming its anti-tumor efficacy. Higher apoptotic cell death, reduced proliferation of cells, and fewer blood vessels were observed in GV1001-treated tumors compared to control. In addition, significant reduction of Tie2+ CD11b+ monocytes, which were recruited by VEGF from tumor cells and play a critical role in angiogenesis, was observed in GV1001-treated tumors. Collectively, the results suggest that GV1001 possesses potential therapeutic efficacy in addition to its ability to induce anti-cancer immune responses by suppressing both HSP70 and HSP90. GV1001 is a 16-amino-acid vaccine peptide derived from the human telomerase reverse transcriptase sequence. We investigated the effects of GV1001 against β-amyloid (Aβ) oligomer-induced neurotoxicity in rat neural stem cells (NSCs). Primary culture NSCs were treated with several concentrations of GV1001 and/or Aβ₂₅₋₃₅ oligomer for 48 hours. GV1001 protected NSCs against the Aβ₂₅₋₃₅ oligomer in a concentration-dependent manner. Aβ₂₅₋₃₅ concentration dependently decreased viability, proliferation, and mobilization of NSCs and GV1001 treatment restored the cells to wild-type levels. Aβ₂₅₋₃₅ increased free radical levels in rat NSCs while combined treatment with GV1001 significantly reduced these levels. In addition, GV1001 treatment of Aβ₂₅₋₃₅-injured NSCs increased the expression level of survival-related proteins, including mitochondria-associated survival proteins, and decreased the levels of death and inflammation-related proteins, including mitochondria-associated death proteins. Together, these results suggest that GV1001 possesses neuroprotective effects against Aβ₂₅₋₃₅ oligomer in NSCs and that these effects are mediated through mimicking the extra-telomeric functions of human telomerase reverse transcriptase, including the induction of cellular proliferation, anti-apoptotic effects, mitochondrial stabilization, and anti-aging and anti-oxidant effects. BACKGROUND: Ischemia reperfusion injury (IRI) is a common complication after kidney transplantation. Peptide GV1001 is a peptide vaccine representing a 16-amino acid human telomerase reverse transcriptase sequence, which has been reported to possess potential antineoplastic and anti-inflammatory activity. This study aimed to investigate the potential effects of peptide GV1001 on renal IRI. METHODS: Peptide GV1001 was subcutaneously administered to C57BL6/J mice 30 minutes before and 12 hours after bilateral IRI. Sham operation and phosphate-buffered saline (PBS) injection were used as controls. Blood and renal tissues were harvested at 1 day after IRI. RESULTS: Peptide GV1001 treatment significantly attenuated renal functional deterioration after IRI (peptide GV1001 group vs PBS group; blood urea nitrogen, P < .05; creatinine, P < .05). Peptide GV1001 treatment also attenuated renal tissue injury (tubular injury score; the peptide GV1001 group vs PBS group; P < .001). Renal apoptosis was also lower in the peptide GV1001 group. Immunohistochemical studies showed that IRI increased perirenal infiltration of both neutrophils and macrophages, and that peptide GV1001 significantly attenuated this process. Expression of interleukin-6 and monocyte chemotactic protein-1 was significantly reduced by peptide GV1001 treatment. CONCLUSIONS: Peptide GV1001 ameliorates acute renal IRI by reducing inflammation and apoptosis; therefore, it is promising as a potential therapeutic agent for renal IRI. The mechanisms of protection should be explored in further studies. Telomerase is expressed in 85-90 % of pancreatic adenocarcinomas and might be a target for active cancer immunotherapy. A study was conducted to investigate safety and immunogenicity in non-resectable pancreatic carcinoma patients using a 16-amino acid telomerase peptide (GV1001) for vaccination in combination with GM-CSF and gemcitabine as first line treatment. Three different vaccine treatment schedules were used; [A (n=6), B (n=6) and C (n=5)]. Groups A/B received GV1001, GM-CSF and gemcitabine concurrently. Group C received initially GV1001 and GM-CSF while gemcitabine was added at disease progression. Group D (n=4) was treated with gemcitabine alone. Adverse events (AE) related to vaccination were mild (grades I-II). Grade III AEs were few and transient. An induced GV 1001‑specific immune response was defined as an increase ≥2 above the baseline value in one of the assays (DTH, proliferation, ELISPOT and cytokine secretion assays, respectively). A telomerase‑specific immune response was noted in 4/6 patients in group A, 4/6 patients in group B and 2/5 patients in group C. An induced ras‑specific immune response (antigenic spreading) was seen in 5 of the 17 patients. The cytokine pattern was that of a Th1-like profile. A treatment induced telomerase or ras response was also noted in group D. All responses were weak and transient. A significant decrease in regulatory T-cells over time was noted in patients in groups A and B (p<0.05). Telomerase vaccination (GV1001) in combination with chemotherapy appeared to be safe but the immune responses were weak and transient. Measures have to be taken to optimize immune responses of GV1001 for it to be considered of clinical interest. BACKGROUND: We aimed to assess the efficacy and safety of sequential or simultaneous telomerase vaccination (GV1001) in combination with chemotherapy in patients with locally advanced or metastatic pancreatic cancer. METHODS: TeloVac was a three-group, open-label, randomised phase 3 trial. We recruited patients from 51 UK hospitals. Eligible patients were treatment naive, aged older than 18 years, with locally advanced or metastatic pancreatic ductal adenocarcinoma, and Eastern Cooperative Oncology Group performance status of 0-2. Patients were randomly assigned (1:1:1) to receive either chemotherapy alone, chemotherapy with sequential GV1001 (sequential chemoimmunotherapy), or chemotherapy with concurrent GV1001 (concurrent chemoimmunotherapy). Treatments were allocated with equal probability by means of computer-generated random permuted blocks of sizes 3 and 6 in equal proportion. Chemotherapy included six cycles of gemcitabine (1000 mg/m(2), 30 min intravenous infusion, at days 1, 8, and 15) and capecitabine (830 mg/m(2) orally twice daily for 21 days, repeated every 28 days). Sequential chemoimmunotherapy included two cycles of combination chemotherapy, then an intradermal lower abdominal injection of granulocyte-macrophage colony-stimulating factor (GM-CSF; 75 μg) and GV1001 (0·56 mg; days 1, 3, and 5, once on weeks 2-4, and six monthly thereafter). Concurrent chemoimmunotherapy included giving GV1001 from the start of chemotherapy with GM-CSF as an adjuvant. The primary endpoint was overall survival; analysis was by intention to treat. This study is registered as an International Standard Randomised Controlled Trial, number ISRCTN4382138. FINDINGS: The first patient was randomly assigned to treatment on March 29, 2007, and the trial was terminated on March 27, 2011. Of 1572 patients screened, 1062 were randomly assigned to treatment (358 patients were allocated to the chemotherapy group, 350 to the sequential chemoimmunotherapy group, and 354 to the concurrent chemoimmunotherapy group). We recorded 772 deaths; the 290 patients still alive were followed up for a median of 6·0 months (IQR 2·4-12·2). Median overall survival was not significantly different in the chemotherapy group than in the sequential chemoimmunotherapy group (7·9 months [95% CI 7·1-8·8] vs 6·9 months [6·4-7·6]; hazard ratio [HR] 1·19, 98·25% CI 0·97-1·48, p=0·05), or in the concurrent chemoimmunotherapy group (8·4 months [95% CI 7·3-9·7], HR 1·05, 98·25% CI 0·85-1·29, p=0·64; overall log-rank of χ(2)2df=4·3; p=0·11). The commonest grade 3-4 toxic effects were neutropenia (68 [19%] patients in the chemotherapy group, 58 [17%] patients in the sequential chemoimmunotherapy group, and 79 [22%] patients in the concurrent chemoimmunotherapy group; fatigue (27 [8%] in the chemotherapy group, 35 [10%] in the sequential chemoimmunotherapy group, and 44 [12%] in the concurrent chemoimmunotherapy group); and pain (34 [9%] patients in the chemotherapy group, 39 [11%] in the sequential chemoimmunotherapy group, and 41 [12%] in the concurrent chemoimmunotherapy group). INTERPRETATION: Adding GV1001 vaccination to chemotherapy did not improve overall survival. New strategies to enhance the immune response effect of telomerase vaccination during chemotherapy are required for clinical efficacy. FUNDING: Cancer Research UK and KAEL-GemVax.
Which is the E3 ubiquitin ligase which ubiquitinates IkB leading to its proteasomal degradation?
IκB degradation involves ubiquitination mediated by a specific E3 ubiquitin ligase SCF(β-TrCP). SCF(β-TrCP) -mediated IκB ubiquitination and degradation is a very efficient process, often resulting in complete degradation of the key inhibitor IκBα within a few minutes of cell stimulation.
NF-kappaB (nuclear factor-kappaB) is a collective name for inducible dimeric transcription factors composed of members of the Rel family of DNA-binding proteins that recognize a common sequence motif. NF-kappaB is found in essentially all cell types and is involved in activation of an exceptionally large number of genes in response to infections, inflammation, and other stressful situations requiring rapid reprogramming of gene expression. NF-kappaB is normally sequestered in the cytoplasm of nonstimulated cells and consequently must be translocated into the nucleus to function. The subcellular location of NF-kappaB is controlled by a family of inhibitory proteins, IkappaBs, which bind NF-kappaB and mask its nuclear localization signal, thereby preventing nuclear uptake. Exposure of cells to a variety of extracellular stimuli leads to the rapid phosphorylation, ubiquitination, and ultimately proteolytic degradation of IkappaB, which frees NF-kappaB to translocate to the nucleus where it regulates gene transcription. NF-kappaB activation represents a paradigm for controlling the function of a regulatory protein via ubiquitination-dependent proteolysis, as an integral part of a phosphorylationbased signaling cascade. Recently, considerable progress has been made in understanding the details of the signaling pathways that regulate NF-kappaB activity, particularly those responding to the proinflammatory cytokines tumor necrosis factor-alpha and interleukin-1. The multisubunit IkappaB kinase (IKK) responsible for inducible IkappaB phosphorylation is the point of convergence for most NF-kappaB-activating stimuli. IKK contains two catalytic subunits, IKKalpha and IKKbeta, both of which are able to correctly phosphorylate IkappaB. Gene knockout studies have shed light on the very different physiological functions of IKKalpha and IKKbeta. After phosphorylation, the IKK phosphoacceptor sites on IkappaB serve as an essential part of a specific recognition site for E3RS(IkappaB/beta-TrCP), an SCF-type E3 ubiquitin ligase, thereby explaining how IKK controls IkappaB ubiquitination and degradation. A variety of other signaling events, including phosphorylation of NF-kappaB, hyperphosphorylation of IKK, induction of IkappaB synthesis, and the processing of NF-kappaB precursors, provide additional mechanisms that modulate the level and duration of NF-kappaB activity. Although constitutive activation of beta-catenin/Tcf signalling is implicated in the development of human cancers, the mechanisms by which the beta-catenin/Tcf pathway promotes tumorigenesis are incompletely understood. Messenger RNA turnover has a major function in regulating gene expression and is responsive to developmental and environmental signals. mRNA decay rates are dictated by cis-acting elements within the mRNA and by trans-acting factors, such as RNA-binding proteins (reviewed in refs 2, 3). Here we show that beta-catenin stabilizes the mRNA encoding the F-box protein betaTrCP1, and identify the RNA-binding protein CRD-BP (coding region determit-binding protein) as a previously unknown target of beta-catenin/Tcf transcription factor. CRD-BP binds to the coding region of betaTrCP1 mRNA. Overexpression of CRD-BP stabilizes betaTrCP1 mRNA and elevates betaTrCP1 levels (both in cells and in vivo), resulting in the activation of the Skp1-Cullin1-F-box protein (SCF)(betaTrCP) E3 ubiquitin ligase and in accelerated turnover of its substrates including IkappaB and beta-catenin. CRD-BP is essential for the induction of both betaTrCP1 and c-Myc by beta-catenin signalling in colorectal cancer cells. High levels of CRD-BP that are found in primary human colorectal tumours exhibiting active beta-catenin/Tcf signalling implicates CRD-BP induction in the upregulation of betaTrCP1, in the activation of dimeric transcription factor NF-kappaB and in the suppression of apoptosis in these cancers. The nuclear factor-κB (NF-κB) signaling pathway is a busy ground for the action of the ubiquitin-proteasome system; many of the signaling steps are coordinated by protein ubiquitination. The end point of this pathway is to induce transcription, and to this end, there is a need to overcome a major obstacle, a set of inhibitors (IκBs) that bind NF-κB and prohibit either the nuclear entry or the DNA binding of the transcription factor. Two major signaling steps are required for the elimination of the inhibitors: activation of the IκB kinase (IKK) and degradation of the phosphorylated inhibitors. IKK activation and IκB degradation involve different ubiquitination modes; the latter is mediated by a specific E3 ubiquitin ligase SCF(β-TrCP) . The F-box component of this E3, β-TrCP, recognizes the IκB degron formed following phosphorylation by IKK and thus couples IκB phosphorylation to ubiquitination. SCF(β-TrCP) -mediated IκB ubiquitination and degradation is a very efficient process, often resulting in complete degradation of the key inhibitor IκBα within a few minutes of cell stimulation. In vivo ablation of β-TrCP results in accumulation of all the IκBs and complete NF-κB inhibition. As many details of IκB-β-TrCP interaction have been worked out, the development of β-TrCP inhibitors might be a feasible therapeutic approach for NF-κB-associated human disease. However, we may still need to advance our understanding of the mechanism of IκB degradation as well as of the diverse functions of β-TrCP in vivo.
Is c-met involved in the activation of the Akt pathway?
HGF-induced activation of c-Met is playing a pivotal role in the stimulation of c-Src activation, resulting in induction of phosphatidylinositol 3-kinase complexes p85α/p110α and p85α/p110δ, which is required for Akt-mediated activation of mammalian target of rapamycin, with consequent inhibition of IκB kinase and nuclear factor-κB activation, resulting in enhanced cell survival.
Acute irreparable UV-induced DNA damage leads to apoptosis of epidermal keratinocytes (KC) and the formation of sunburn cells, whereas less severely damaged cells survive but harbor the potential of tumor formation. Here we report that hepatocyte growth factor/scatter factor (HGF/SF) prevents UVB-induced apoptosis in primary KC cultured in vitro. When we analyzed the signaling pathways initiated by the HGF/SF receptor c-met, we found that the phosphatidylinositol (PI) 3-kinase and its downstream-element AKT and the mitogen-activated protein (MAP) kinase were activated. Inhibition of PI 3-kinase led to a complete abrogation of the anti-apoptotic effect of HGF/SF, whereas blockade of the MAP kinase pathway had no effect. In contrast to the observation with primary KC, HGF/SF could not enhance survival after UVB irradiation of HaCaT and A431 cell lines, despite the fact that in these cells the PI 3-kinase and MAP kinase pathways were also activated by HGF/SF. Cell cycle analysis of KC revealed a G(2)/M arrest after UVB irradiation and a complete loss of proliferating cells. Because HGF/SF in the skin is produced by dermal fibroblasts, our findings suggest that the HGF/SF-mediated rescue of KC from apoptosis represents an important paracrine loop by which UVB-damaged KC can be kept alive to maintain the epidermal barrier function but cannot further proliferate, thereby preventing the induction of epithelial skin tumors. The mechanisms by which growth factors trigger signal transduction pathways leading to protection against apoptosis are of great interest. In this study, we investigated the effect of hepatocyte growth factor (HGF/SF) and epidermal growth factor (EGF) on adriamycin (ADR)-induced apoptosis. Treatment of human epithelial MKN74 cells with ADR, a DNA topoisomerase IIalpha inhibitor, caused apoptosis. However, cells pretreated with HGF/SF, but not those pretreated with EGF, were resistant to this apoptosis. The protective effect of HGF/SF against the ADR-induced apoptosis was abolished in the presence of either LY294002, an inhibitor of phosphatidylinositol-3'-OH kinase (PI3-K) or 1L-6-hydroxymethyl-chiro-inositol 2-(R)-2-O-methyl-3-O-octadecylcarbonate, an inhibitor of Akt, thus implicating the activation of PI3-K-Akt signaling in the antiapoptotic action of HGF/SF. Immunoblotting analysis revealed that HGF/SF stimulated the sustained phosphorylation of Akt for several hours but that EGF stimulated the phosphorylation only transiently. Furthermore, ADR-induced activation of caspase-9, a downstream molecule of Akt, was inhibited for at least 24 h after HGF/SF stimulation, but it was not affected by EGF stimulation. Cell-surface biotin-labeling analysis showed that the HGF/SF receptor remained on the cell surface until at least 30 min after HGF/SF addition but that the EGF receptor level on the cell surface was attenuated at an earlier time after EGF addition. These results indicate that HGF/SF, but not EGF, transmitted protective signals against ADR-induced apoptosis by causing sustained activation of the PI3-K-Akt signaling pathway. Furthermore, the difference in antiapoptotic capacity between HGF/SF and EGF is explained, at least in part, by the delayed down-regulation of the HGF/SF receptor. This study determines the effect of hepatocyte growth factor (HGF) on post-infarction left ventricular (LV) remodeling and cardiac function. In mice, on day 1 after myocardial infarction (MI), HGF (0.45 mg/kg per day) was injected into the tail vein for 7 days (n = 12). In the control mice (n = 12), 0.9% sodium chloride was injected instead of HGF. Hemodynamic data were obtained in vehicle treated control and HGF-treated hearts 4 weeks after the onset of MI. In the HGF-treated group, cardiac function was well preserved as indicated by LV pressure-volume relationship. These mice exhibited better LV systolic and diastolic function. The infarcted LV wall in HGF-treated heart was thicker as compared to vehicle treated group. Fibrosis and infarct size of the ventricular wall was significantly reduced in the HGF-treated hearts. 5-Bromo-2'-deoxy-uridine (BrdU) and Ki67 positive cardiomyocytes were observed in the border area of the HGF-treated infarcted hearts. c-Met and c-kit positive cardiomyocytes were observed in the border area and epicardium. Angiogenesis was significantly enhanced in HGF-treated hearts as determined by vessel density per unit area. A significant reduction in apoptosis in the HGF-treated hearts was observed compared with control hearts, and was strongly associated with increased Akt activation. Treatment with HGF improved heart function through angiogenesis, ventricular wall thickening, and hypertrophy of cardiomyocytes. The antiapoptotic effect of HGF was mediated by activation of PI3-kinase/Akt pathway. PURPOSE: The inhibitor of the apoptosis protein (IAP) family members, such as the X-linked IAP (XIAP), survivin, and livin, are essential for cell survival and antiapoptosis in colorectal cancer cells. We hypothesized that the hepatocyte growth factor (HGF) activation in colorectal cancer via c-Met receptor regulates IAP proteins through Akt signaling. EXPERIMENTAL DESIGN: The level of IAPs and C-Met mRNA expression was assessed using a quantitative real-time reverse transcriptase-PCR (RT-PCR) assay on colorectal normal mucosa (n = 13), adenomas (n = 6), and colorectal cancer tumors (n = 50). The role of HGF/C-Met pathway through Akt and XIAP was investigated by small interfering RNA (siRNA) and quantitative RT-PCR analysis of colorectal cancer lines. RESULTS: Of the IAPs, only XIAP showed significant correlation to tumor development and progression. XIAP mRNA level in primary colorectal cancer was significantly higher than that in colorectal normal mucosa (P = 0.01); liver metastases was significantly higher than primary colorectal cancer tumors (P = 0.04); and primary colorectal cancer N1/N2 cases were significantly higher than N0 cases (P = 0.008). HGF stimulation of colorectal cancer lines enhanced XIAP mRNA expression but not other IAPs. Activation of XIAP expression by HGF was inhibited by siRNA targeting Akt1 and Akt2. CONCLUSIONS: Activation of C-MET enhances XIAP through the Akt pathway. XIAP up-regulation was shown to be correlated to colorectal cancer tumor progression. The Akt-XIAP pathway may be a potential molecular target for regulating colorectal cancer progression. Hepatocyte growth factor (HGF) is a pleiotropic cytokine promoting proliferation, migration and survival in several cell types. HGF and its cognate receptor c-Met are expressed in cardiac cells during early cardiogenesis, but data concerning its role in cardiac differentiation of embryonic stem cells (ESCs) and the underlying molecular mechanisms involved are limited. In the present study we show that HGF significantly increases the number of beating embryoid bodies of differentiating ESCs without affecting beating frequency. Furthermore, HGF up-regulates the expression of the cardiac-specific transcription factors Nkx 2.5 and GATA-4 and of markers of differentiated cardiomyocytes, i.e. alpha-MHC, beta-MHC, ANF, MLC2v and Troponin T. The HGF-induced increase in Nkx 2.5 expression was inhibited by co-treatment with the PI3 kinase inhibitors Wortmannin and LY294002, but not by its inactive homolog LY303511, suggesting an involvement of the PI3 kinase/Akt pathway in this effect. We conclude that HGF is an important growth factor involved in cardiac differentiation and/or proliferation of ESCs and may therefore be critical for the in vitro generation of pre- or fully differentiated cardiomyocytes as required for clinical use of embryonic stem cells in cardiac diseases. The FasL-Fas couple is a general death mediator whose activated signals lead to caspase-8 activation and apoptosis in adult hepatocytes. Suppression of caspase-8 activation and cell death is a protective mechanism modulated by the FLICE-Like Inhibitory Protein (FLIP). Although hepatocyte growth factor (HGF) and its receptor Met are known to mediate cell survival in developing livers, the molecular mechanisms involved in this process are poorly understood. We show here that Met activation by HGF impairs Fas-triggered apoptosis of primary embryonic hepatocytes and cell survival correlates with inhibition of caspase-8 and caspase-3 activities. Furthermore, we found that HGF treatment prevents degradation of FLIPL triggered by Fas activation. In contrast to this, Met activation does not modulate FLIPL levels and its stability in untreated cells, thus showing the specificity of this regulatory mechanism for embryonic hepatocyte survival. Knocking down FLIP expression abolishes the ability of Met to inhibit Fas-triggered hepatocyte death, demonstrating the functional requirement of FLIP in HGF anti-apoptotic signals. By combining genetic and pharmacological approaches, we also demonstrate that the PI3K-Akt pathway is required in embryonic hepatocytes to prevent Fas-triggered FLIP degradation and death. Thus, Met acting on PI3K and Akt ensures high levels of FLIPL, and disruption of this pathway contributes to hepatic apoptosis and possibly to Fas-related liver diseases. PURPOSE: Uveal melanoma is the most common primary intraocular maligcy in adult humans. Unlike cutaneous melanoma, uveal melanoma disseminates preferentially to the liver through the hematogenous system. To date, the mechanism underlying this metastatic homing is largely unknown. This study investigated the effect of hepatocyte growth factor (HGF)-triggered signaling pathways to identify the role of HGF and its downstream effectors in inducing the migration of uveal melanoma cells. METHODS: Migration of uveal melanoma cells was measured by in vitro wound healing and transwell migration assays. The expression and translocation of c-Met were detected using indirect immunofluorescence. The activation of extracellular signal-regulated kinase (ERK)1/2 and phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt) pathways was analyzed using specific antibodies against phospho-ERK1/2 and phospho-Akt. The impact of HGF treatment on the expression of cell adhesion molecules was measured using Western blotting. RESULTS: HGF was found to enhance cell migration, and that HGF-induced migration depends on PI3K/Akt pathway. The activation of PI3K/Akt pathway induced by the HGF/c-Met axis is involved in the downregulation of cell adhesion molecules E-cadherin and beta-catenin, contributing to the attenuation of cell-cell adhesion and promoting the enhanced motility and migration of uveal melanoma cells. On HGF stimulation, receptor c-Met is translocated to the nucleus in a ligand-dependent manner, suggesting that c-Met may modulate the expression of genes involved in melanoma cell migration. CONCLUSIONS: Data from this study directly linked the central PI3K/Akt pathway to uveal melanoma migration and pointed to new avenues for therapeutic intervention in hepatic metastasis. During central nervous system development, growth factors and their associated receptor protein tyrosine kinases regulate many neuronal functions such as neurite extension and dendrite maturation. Hepatocyte growth factor (HGF) and its receptor, c-Met, can promote formation of neurites and enhance elaboration of dendrites in mature neurons, but their effects on the early stages of dendrite maturation in hippocampal neurons and the signaling pathways by which they promote dendrite formation have not been studied. Exogenous HGF treatment effectively enhanced the phosphorylation and activation of c-Met in cultured hippocampal neurons at 4 days in vitro. HGF treatment increased the number of dendrites and promoted dendrite elongation in these neurons. Consistent with these results, HGF activated Akt, which phosphorylates glycogen synthase kinase-3beta (GSK-3beta) to inactivate it, and reduced phosphorylation of microtubule-associated protein 2 (MAP2), which can promote microtubule polymerization and dendrite elongation when dephosphorylated. Conversely, pharmacological inhibition of c-Met with its specific inhibitor, PHA-665752, or genetic knock-down of c-Met with short hairpin RNAs (shRNAs) suppressed HGF-induced phosphorylation of Akt and GSK-3beta, increased phosphorylation of MAP2, and reduced dendrite number and length in cultured hippocampal neurons. Moreover, suppressing c-Met with PHA-665752 or by shRNA decreased MAP2 expression. Inhibiting Akt activity with the phosphoinositide-3-kinase inhibitor LY294002 or Akt inhibitor X suppressed HGF-induced phosphorylation of GSK-3beta, increased MAP2 phosphorylation, and blocked the ability of HGF to enhance dendritic length. These observations indicate that HGF and c-Met can regulate the early stages of dendrite maturation via activation of the Akt/GSK-3beta pathway. The development of the mammary gland requires an integrated response to specific growth factors and steroid hormones. Hepatocyte growth factor (HGF) and its tyrosine kinase receptor, MET, are expressed and temporally regulated during mammary development and differentiation. Epidermal growth factor receptor (EGFR) and its ligands have also been implicated in mammary gland growth and morphogenesis. Since both cytokines seem to exert a morphogenic program in this tissue, we have investigated the possible concerted action of EGF and HGF on the HC11 cell line, a widely used model of nontumorigenic mammary cells. Western blot analysis indicated that HC11 expressed MET and EGFR, and showed ERK1/2 and AKT activation following HGF or EGF treatment. Analysis by real-time PCR and western blot showed that after an EGF but not HGF or insulin-like growth factor-I treatment, HC11 mammary cells exhibited an increase in MET expression at both the mRNA and protein levels, which was dependent on the AKT pathway. Simultaneous treatment with HGF and EGF increased proliferation, scatter, and invasion as assessed by cell count, cell cycle, scatter, and transwell assays. AKT inhibition did not influence the cooperation on proliferation or invasion after HGF+EGF treatment, while ERK1/2 inhibition abolished MET/EGFR cooperation on proliferation. HGF+EGF treatment increased the duration of ERK1/2 and AKT activation compared to HGF or EGF alone. All these data indicate that a crosstalk between the EGF and HGF pathways in mammary epithelial cells may modulate the development of the mammary gland. Certain tumor cell responses to the growth factor-inducible early response gene product CCN1/Cyr61 overlap with those induced by the hepatocyte growth factor (HGF)/c-Met signaling pathway. In this study, we investigate if Cyr61 is a downstream effector of HGF/c-Met pathway activation in human glioma cells. A semiquantitative immunohistochemical analysis of 112 human glioma and normal brain specimens showed that levels of tumor-associated Cyr61 protein correlate with tumor grade (P < 0.001) and with c-Met protein expression (r(2) = 0.4791, P < 0.0001). Purified HGF rapidly upregulated Cyr61 mRNA (peak at 30 minutes) and protein expression (peak at 2 hours) in HGF(-)/c-Met(+) human glioma cell lines via a transcription- and translation-dependent mechanism. Conversely, HGF/c-Met pathway inhibitors reduced Cyr61 expression in HGF(+)/c-Met(+) human glioma cell lines in vitro and in HGF(+)/c-Met(+) glioma xenografts. Targeting Cyr61 expression with small interfering RNA (siRNA) inhibited HGF-induced cell migration (P < 0.01) and cell growth (P < 0.001) in vitro. The effect of Cyr61 on HGF-induced Akt pathway activation was also examined. Cyr61 siRNA had no effect on the early phase of HGF-induced Akt phosphorylation (Ser(473)) 30 minutes after stimulation with HGF. Cyr61 siRNA inhibited a second phase of Akt phosphorylation measured 12 hours after cell stimulation with HGF and also inhibited HGF-induced phosphorylation of the Akt target glycogen synthase kinase 3alpha. We treated preestablished subcutaneous glioma xenografts with Cyr61 siRNA or control siRNA by direct intratumoral delivery. Cyr61 siRNA inhibited Cyr61 expression and glioma xenograft growth by up to 40% in a dose-dependent manner (P < 0.05). These results identify a Cyr61-dependent pathway by which c-Met activation mediates cell growth, cell migration, and long-lasting signaling events in glioma cell lines and possibly astroglial maligcies. Hepatocyte growth factor modulates activation and antigen-presenting cell function of dendritic cells. However, the molecular basis for immunoregulation of dendritic cells by hepatocyte growth factor is undefined. In the current study, we demonstrate that hepatocyte growth factor exhibits inhibitory effect on dendritic cell activation by blocking IκB kinase activity and subsequent nuclear factor-κB activation. Inhibition of IκB kinase is mediated by hepatocyte growth factor-induced activation of c-Src. Proximal signaling events induced in dendritic cells by hepatocyte growth factor include a physical association of c-Src with the hepatocyte growth factor receptor c-MET and concomitant activation of c-Src. Activation of c-Src in turn establishes a complex consisting of phosphatidylinositol 3-kinase and c-MET, and promotes downstream activation of the phosphatidylinositol 3-kinase/AKT pathway and mammalian target of rapamycin. Blocking activation of c-Src, phosphatidylinositol 3-kinase and mammalian target of rapamycin prevents hepatocyte growth factor-induced inhibition of IκB kinase, nuclear factor-κB and dendritic cell activation. Notably, hepatocyte growth factor-stimulated c-Src activation results in induction of phosphatidylinositol 3-kinase complexes p85α/p110α and p85α/p110δ, which is required for activation of mammalian target of rapamycin, and consequent inhibition of IκB kinase and nuclear factor-κB activation. Our findings, for the first time, have identified the c-Src-phosphatidylinositol 3-kinase-AKT-mammalian target of rapamycin pathway that plays a pivotal role in mediating the inhibitory effects of hepatocyte growth factor on dendritic cell activation by blocking nuclear factor-κB signaling. Hepatocyte growth factor (HGF) is up-regulated in tissue repair and has been implicated in playing a role in this process through its anti-apoptotic and proliferative activities. Cyclooxygenase-2 (COX-2) is an inducible enzyme in the biosynthetic pathway of prostaglandins, and its activation has been shown to play an important role in cell growth. We previously reported that HGF significantly inhibited anoikis, possibly through the up-regulation of COX-2 expression in the endometrial RL95-2 cancer cell line. Here, we report that i) treatment of RL95-2 cells with HGF resulted in phosphorylation of the HGF receptor c-Met, activation of Akt and IκB, translocation of NF-κB into the nucleus, and up-regulation of COX-2 mRNA; ii) the IκB-α phosphorylation inhibitor BAY11-7082 and the selective COX-2 inhibitor CAY10452 blocked HGF-mediated anoikis resistance in RL95-2 cells; and iii) HGF induced migration and invasion in RL95-2 cells, while the phosphatidylinositol 3-kinase (PI3K) inhibitor LY294002 and CAY10452 blocked these effects of HGF stimulation. Our data suggest that HGF possesses chemotactic ability, has anti-apoptosis action, and induces cellular infiltration via the PI3K/Akt pathway; it also triggers NF-κB activation and up-regulates COX-2 gene expression in endometrial cancer cells. Osteosarcoma is a common maligt bone tumor. Cisplatin (CDDP) achieves a high response rate in osteosarcoma. However, osteosarcoma usually exhibits cisplatin resistance. Many members of receptor tyrosine kinases (RTKs)(1) have been demonstrated to be overexpressed and constitutively activated in various tumors including osteosarcoma, resulting in maligt progression and insensitivity to chemotherapy. Hepatocyte growth factor receptor (HGFR/c-Met) also appears overexpressed and activated in osteosarcoma cells. Nevertheless, which role of c-Met activation in cisplatin efficacy against osteosarcoma cells remains still elusive. This study found that inhibition of c-Met activity by PHA-665752 or blockade of the interaction of autocrined HGF with c-Met with neutralizing anti-HGF antibody promoted cisplatin efficacy in osteosarcoma cells, while addition of recombit human HGF (rh-HGF) counteracts cisplatin cytotoxicity. Specifically, we demonstrated that inhibition of c-Met activity led to suppression of the PI3K-Akt pathway, thus enhancing cisplatin chemosensitivity. Our study clearly suggests that inhibition of c-Met activity can effectively sensitize osteosarcoma cells to cisplatin via suppression of the PI3K-Akt signaling. Epithelial-mesenchymal transition (EMT) has recently been studied to elucidate mechanisms of the liver metastatic process. We investigated EMT in the process of liver metastasis and the effects of chemotherapy on EMT cells as therapeutic strategy for colorectal liver metastasis. We used the CT26 murine colorectal carcinoma cell line to create an in vivo mouse liver metastasis model. Liver tumors were stained immuno-histochemically. Expression of proteins associated with TGF-β/Smad and hepatocyte growth factor (HGF)/c-Met pathways were investigated by western blotting. Cells with c-Met mRNA knockdown by siRNA techniques showed clearly reduced liver metastases compared with regular cells at 21 days. TGF-β and HGF induced EMT expression, but signal transduction was quite different. TGF-β induced ERK, but not Akt phosphory-lation. HGF mediated both ERK and Akt phosphorylation. Akt inhibitor blocked Akt phosphorylation but did not affect TGF-β-induced activation of ERK, Snail and Slug. U-0126 did not reduce Snail activity by TGF-β at a concentration to block ERK phosphorylation. However, Akt inhibitor and U-0126 completely inhibited HGF-induced Slug activation. 5-FU mediated cell death in the EMT process induced by TGF-β more effectively than HGF. ERK/Akt signaling, but not the Smad pathway, may be one of the main processes in HGF-induced EMT, despite the Smad pathway, but not ERK/Akt, being critical for TGF-β-induced EMT. The MAPK/Akt pathway is indispensable in HGF/c-Met signaling. The ERK/Akt pathway particularly may be critical in the HGF-induced EMT process. However, long-term use of chemotherapeutic agents may induce drug resistance and distant metastases through EMT-related signaling pathway activation. A better understanding of the pathophysiology and evolution of non-small cell lung cancer (NSCLC) has identified a number of molecular targets and spurred development of novel targeted therapeutic agents. The MET receptor tyrosine kinase and its ligand hepatocyte growth factor (HGF) are implicated in tumor cell proliferation, migration, invasion, and angiogenesis in a broad spectrum of human cancers, including NSCLC. Amplification of MET has been reported in approximately 5%-22% of lung tumors with acquired resistance to small-molecule inhibitors of the epidermal growth factor receptor (EGFR). Resistance to EGFR inhibitors is likely mediated through downstream activation of the phosphoinositide 3-kinase /AKT pathway. Simultaneous treatment of resistant tumors with a MET inhibitor plus an EGFR inhibitor can abrogate activation of downstream effectors of cell growth, proliferation, and survival, thereby overcoming acquired resistance to EGFR inhibitors. Development and preclinical testing of multiple agents targeting the HGF-MET pathway, including monoclonal antibodies targeting HGF or the MET receptor and small-molecule inhibitors of the MET tyrosine kinase, have confirmed the crucial role of this pathway in NSCLC. Several agents are now in phase III clinical development for the treatment of NSCLC. This review summarizes the role of MET in the pathophysiology of NSCLC and in acquired resistance to EGFR inhibitors and provides an update on progress in the clinical development of inhibitors of MET for treatment of NSCLC.
Is pregnancy an additional risk during during H1N1 infection?
Pregnant women are at increased risk for complications from pandemic influenza H1N1 virus infection. Pregnant women, because of their altered immunity and physiological adaptations, are at higher risk of developing pulmonary complications, especially in the second and third trimesters. Pregnancy, particularly during the third trimester, increases the risk of complications and early antiviral treatment is associated with improved outcomes.
BACKGROUND: Pregt women have been identified as a group at risk of increased morbidity and mortality associated with the pandemic H1N1 influenza A 2009 (H1N1/09) outbreak. METHODS: Six hospitals in the state of Victoria, Australia, contributed retrospective and prospective demographic and clinical data, reason for admission data, and maternal and fetal outcome data for women with laboratory-confirmed H1N1/09 admitted to the hospital from 20 May 2009 through 31 July 2009. RESULTS: Forty-three cases were reported during the study period, including 8 intensive care unit admissions, 1 maternal death, 2 fetal deaths, and 1 neonatal death. The most common reason for admission was uncomplicated influenza-like illness. Patients hospitalized for uncomplicated influenza-like illness had a length of stay significantly less than those with confirmed pneumonia. Thirty-six percent of women delivered during the hospitalization. Of the women delivering before 37 weeks' gestation, almost all had pneumonia. Almost half of our case series had no other comorbidity, a large proportion (77%) of women received antivirals, and 56% received antibiotics. The incidence of hospitalization was estimated at 0.46% (95% confidence interval, 0.31%-0.66%) of all 6094 pregt women in the third trimester during the 3-month study period. The incidence of hospitalization in the second trimester was estimated at 0.21% (95% confidence interval, 0.11%-0.36%). CONCLUSIONS: This case series confirms a high number of complications in pregt women due to pandemic H1N1/09. Many of these women had comorbidities, although almost 50% of the women in this case series who required hospitalization did not have an additional risk factor other than being pregt. BACKGROUND: Pregt women have been identified as a group at risk, both for respiratory complications than for the admissions to the Intensive Care Unit (ICU) during the 2009 H1N1 influenza pandemic (pdm). The purpose of this prospective register-based cohort-study was to characterize the clinical virulence of the pdm (H1N1/09)v during pregcy in La Réunion. METHODS/PRINCIPAL FINDINGS: Over a twelve-week pdm wave (13 July to 3 October 2009), 294 pregt women presented with an influenza-like illness (ILI) to one of the three maternity departments of the South Reunion area, Indian Ocean. Out of these, 278 were checked by RT-PCR for influenza viruses (157 positive and 121 negative, of whom, 141 with pdm flu and 132 with ILIs of non pdm origin, 5 untyped). The median body temperature was higher in women experiencing pdm flu than in those with non pdm ILI (38.9 degrees C versus 38.3 degrees C, P<0.0001), without evidence linked to circulating viremia. Oseltamivir was given for 86% of pdm flu cases in a median time inferior than 48 hrs (range 0-7 days). The hospitalization rate for pdm flu was of 60% and not associated with underlying conditions. Six viral pneumonia and fourteen asthma attacks were observed among 84 hospitalized pdm flu cases, of whom, only one led to the ICU for an acute lung injury. No maternal death occurred during the pdm wave. None adverse pregcy outcome was associated with pdm flu. No congenital birth defect, nor early-onset neonatal influenza infection was attributable to pdm flu exposure. CONCLUSIONS/SIGNIFICANCE: This report mitigates substantially the presumed severity of pandemic H1N1/09 influenza infection during pregcy. The reasons for which the clinical burden of H1N1/09 influenza virus may differ worldwide raise questions about a differential local viral-strain effect and public health preparedness, notably in timely access to special care and antiviral treatments. BACKGROUND: Emerging data suggest that pregcy conveys high risk for severe complications from the 2009 pandemic influenza A virus (2009 H1N1) infection. CASE: We describe an infected pregt woman with critical illness owing to acute respiratory distress syndrome despite previous vaccination. Early serologic testing indicated absent immunity, followed 11 days later by a robust immune response. The patient required mechanical ventilation for 11 days, but ultimately improved, and was discharged home on hospital day 14. CONCLUSION: With the expectation that 2009 H1N1 will continue to cause disease in the immediate future, the virus has been included as a component of the 2010-2011 seasonal influenza vaccine. Vaccination of pregt women is strongly encouraged. However, regardless of vaccination history, clinicians should remain vigilant for 2009 H1N1 infection when the virus is in circulation, and should not delay antiviral treatment of pregt women with suspected influenza. AIM: Evaluation of alterations of immune response regulation and possible risk of antenatal development of fetus in postvaccination period in pregt women immunized against influenza A (H1N1). MATERIALS AND METHODS: Women were vaccinated with MonoGrippol plus vaccine in the II trimester of physiological pregcy. At certain intervals ofthe vaccination period (before the vaccination, 7 and 30 days after the vaccination) major biochemical markers in blood sera (alanine aminotransferase, aspartate aminotransferase, lactate dehydrogenase, alkaline phosphatase, creatinine, urea) and levels of key cytokines in spontaneous and stimulated test (IL-1alpha, IL-1RA, IL-2, IL-4, IL-10, IFNgamma, TNFalpha) were evaluated. Vaccination safety for the fetus and trophoblast development was evaluated by using human chorionic gonadotropin (HCG), alpha-fetoprotein (AFP) and trophoblasitc beta-1-glycoprotein (TBG) levels. RESULTS: During vaccination in 13% of cases mild local reactions were noted, in 26.1%--general systemic reactions in the form of weakness, dizziness and headaches. Levels of major biochemical markers at days 7 and 30 after the vaccination did not have any significant difference from the initial values (p > 0.05). Cytokine levels in spontaneous and stimulated tests also did not change significantly. Markers of the course of pregcy and fetus development (HCG, AFP and TBG) in the two groups observed had comparable values. CONCLUSION: Vaccination of pregt women against influenza A (H1N1) by Russian subunit formulation (MonoGrippol plus) showed reactogenicity comparable to control group by the level of influence on general metabolic and immunologic homeostasis and on the course of pregcy, which is an evidence of its safety. OBJECTIVES: To describe the clinical characteristics of the pregt women who were hospitalized in a tertiary referral hospital with pandemic influenza H1N1 2009 virus infection and neonatal outcomes from October 2009 to December 2009 during which the pandemic influenza cases peaked in Turkey. MATERIALS AND METHODS: Twenty-five pregt women who were hospitalized with influenza-like illness and who had laboratory confirmation for pandemic influenza H1N1 virus infection were evaluated prospectively. RESULTS: Of the 25 patients, 4 (16%) were in the first trimester, 8 (32%) were in the second trimester, and 13 (52%) were in the third trimester. The median time from the onset of symptoms to the initiation of antiviral therapy was 1 day (range 1-9 days). Nineteen (76%) patients received oseltamivir treatment. It took 1.6 days on the average for the fever defervescence after the initiation of treatment or hospitalization. Of the 14 patients who underwent chest radiography, three had findings consistent with pneumonia. The mean duration of hospitalization was 4.8 days. Four women (16%) were admitted to an intensive care unit, but there were no maternal or neonatal deaths in this series. At the time of their H1N1 hospitalization, seven women delivered by cesarean at 33-40 weeks gestation, two vaginally at 38 weeks gestation, and two had an abortion at 10 weeks and 16 weeks of gestation, respectively. None of the infants had any evidence of influenza infection. CONCLUSION: Pregt women are at increased risk for complications from pandemic influenza H1N1 virus infection. Timely medical attention with early recourse to antiviral therapy is associated with a better outcome in H1N1-affected pregt women. The aim of this study was to verify whether pregcy was a risk factor for death in influenza A (H1N1)/2009 infection. We compared the case-fatality rates for pandemic influenza among non-pregt women of childbearing age and pregt women, besides investigating other factors that differentiated the groups in relation to the outcomes. The data were collected from the National Information System on Diseases of Notification (SINAN), of the Ministry of Health. The study used cases with laboratory confirmation and included 1,861 women from 10 to 49 years of age, of whom 352 were pregt. The case-fatality rate during the 2009 pandemic was 4.5% for pregt women and 6.4% for non-pregt women (p = 0.197). Logistic regression did not show an association between pregcy and death (OR = 0.7; 95%CI: 0.41-1.21). However, there were significant differences between the two groups in relation to mean age, treatment with oseltamivir, schooling, and presence of other risk factors. OBJECTIVE: Because pregcy suppresses the immune system, women at any stage of pregcy are more susceptible to bacterial and viral infection. Pregt women might thus be at increased risk of complications from pandemic H1N1 virus infection, and illness may progress rapidly. CASE REPORT: A 23-year-old primigravida at 9 weeks' gestation was presented to our institution because of the sudden onset of sore throat, fever, chills, and vomiting for 5 days. She was diagnosed with early pregcy H1N1 infection, vulvar herpes infection, and impending intravascular disseminated coagulopathy. Oseltamivir (Tamiflu) 75 mg and valacyclovir 500 mg were then administered orally twice daily for 5 days. The patient's fever, chills, and vomiting subsided 2 days later. The real-time reverse-transcriptase polymerase chain reaction (RT-PCR) analysis of nasal discharge for influenza virus types A and B showed positive results for the A/H1N1 influenza virus. The early pregcy was terminated by therapeutic curettage at the patient's request. The surgical specimen revealed products of conception with the presence of necrotic chorionic villi, and focal lymphocytes in decidual tissue. RT-PCR analysis of gestational tissue for A/H1N1 was negative. CONCLUSION: Pregt women with H1N1 infection seem to benefit from antiviral therapy. OBJECTIVE: To investigate whether an adjuvanted pandemic A/H1N1 2009 influenza vaccine in pregcy was associated with an increased risk of fetal death. DESIGN: Nationwide register based cohort study. SETTING: Denmark. PARTICIPANTS: All clinically recognised singleton pregcies that ended between November 2009 and September 2010. Individual level data on exposure to an inactivated AS03 pandemic A/H1N1 2009 influenza vaccine (Pandemrix) and potential confounders were linked to the study cohort using a unique person identifier. MAIN OUTCOME MEASURES: The primary outcome measure was risk of fetal death (spontaneous abortion and stillbirth combined) in H1N1 vaccinated compared with unvaccinated pregcies, adjusting for propensity scores. Secondary outcome measures were spontaneous abortion (between seven and 22 weeks' gestation) and stillbirth (after 22 completed weeks' gestation). RESULTS: The cohort comprised 54,585 pregcies; 7062 (12.9%) women were vaccinated against pandemic A/H1N1 2009 influenza during pregcy. Overall, 1818 fetal deaths occurred (1678 spontaneous abortions and 140 stillbirths). Exposure to the H1N1 vaccine was not associated with an increased risk of fetal death (adjusted hazard ratio 0.79, 95% confidence interval 0.53 to 1.16), or the secondary outcomes of spontaneous abortion (1.11, 0.71 to 1.73) and stillbirth (0.44, 0.20 to 0.94). Estimates for fetal death were similar in pregt women with (0.82, 0.44 to 1.53) and without comorbidities (0.77, 0.47 to 1.25). CONCLUSION: This large cohort study found no evidence of an increased risk of fetal death associated with exposure to an adjuvanted pandemic A/H1N1 2009 influenza vaccine during pregcy. BACKGROUND: A(H1N1)v2009 influenza vaccination of pregt women was a challenge for health care providers, as little safety data were available. METHODS: We prospectively followed the pregcies of women who were vaccinated at any time during pregcy or ≤ 4 weeks prior to conception and compared these outcomes to a control cohort matched by the estimated date of birth. Primary endpoints: rate of spontaneous abortion and major malformations. Secondary endpoints: preeclampsia, gestational age at birth, and birth weight. RESULTS: Pregcy outcome of 323 women immunized with adjuvanted or non-adjuvanted A(H1N1)v2009 influenza vaccines from 2009-09-28 to 2010-03-31 were compared to 1329 control subjects. The risk for spontaneous abortions (HR 0.89; 95% CI 0.36-2.19) and the rate of major malformations (all trimesters: OR 0.87; 95% CI 0.38-1.77; preconception and first trimester exposure: OR 0.79; 95% CI 0.13-2.64) did not vary between the two cohorts. Furthermore, there was no increase in preeclampsia, prematurity, and intrauterine growth retardation in the vaccinated cohort. CONCLUSION: The results of our study do not indicate a risk for the pregt woman and the developing embryo/fetus after H1N1 vaccination. We provide and apply methods novel in observational studies on pregcy outcome, especially if a single dose exposure is investigated. The Influenza A H1N1 pandemic (A H1N1) occurred between June 2009 and August 2010. Although the pandemic is now over, the virus has emerged as the predomit strain in the current seasonal influenza phase in the northern hemisphere. The A H1N1 influenza is a novel strain of the influenza A virus and is widely known as swine flu. The virus contains a mixture of genetic material from human, pig and bird flu virus. It is a new variety of flu which people have not had much immunity to. Much has been learnt from the Pandemic of 2009/2010 but the messages about vaccination and treatment seem to be taken slowly by the clinical profession. Most people affected by the virus, including pregt women, suffer a mild viral illness, and make a full recovery. The median duration of illness is around seven days. This influenza typically affects the younger age group i.e. from the ages of 5-65 years. Current experience shows that the age group experiencing increased morbidity and mortality rates are in those under 65 years of age. Pregt women, because of their altered immunity and physiological adaptations, are at higher risk of developing pulmonary complications, especially in the second and third trimesters. In the United Kingdom, twelve maternal deaths were reported to be associated with the H1N1 virus during the pandemic and clear avoidable factors were identified (Modder, Review of Maternal Deaths in the UK related to A H1N1 2009 influenza (CMACE). www.cmace.org.uk, 2010). The pregcy outcomes were also poor for women who were affected by the virus with a fivefold increase in the perinatal mortality rate and threefold increase in the preterm delivery rate (Yates et al. Health Technol Assess 14(34):109-182, 2010). There continues to be a low uptake of the flu vaccine and commencement of antiviral treatment for pregt women. BACKGROUND: Pregt women were at increased risk for serious outcomes of 2009 pandemic influenza A virus subtype H1N1 (influenza A[H1N1]pdm09) infection, but little is known about the overall impact of the pandemic on neonatal and maternal outcomes. METHODS: We identified live births that occurred from 1 July 2008 through 31 May 2010 in 5 Kaiser Permanente regions. Pregt women were considered to have influenza if they had a positive result of a laboratory test for influenza virus or if they received a diagnosis of influenza during a period in which seasonal influenza virus or A(H1N1)pdm09 was the predomit circulating virus. RESULTS: There were 111 158 births from 109 015 pregcies involving 107 889 mothers; 368 pregt women (0.3%) received a diagnosis of influenza due to seasonal virus, and 959 (0.9%) received a diagnosis of influenza due to A(H1N1)pdm09; 107 688 did not receive an influenza diagnosis. Pregt women with influenza due to A(H1N1)pdm09 were more likely than women with seasonal influenza infection to be hospitalized within 30 days of the diagnosis (27% vs 12%; odds ratio [OR], 2.84 [95% confidence interval {CI}, 2.01-4.02]). Pregt women with A(H1N1)pdm09 who started antiviral treatment ≥2 days after the diagnosis were significantly more likely to be hospitalized than those who started antiviral treatment <2 days after diagnosis (OR, 3.43 [95% CI, 1.55-7.56]). Mothers with seasonal influenza virus infection had an increased risk for having a small-for-gestational-age infant (OR, 1.59 [95% CI, 1.15-2.20]). CONCLUSIONS: In this large, geographically diverse population, A(H1N1)pdm09 infection increased the risk for hospitalization during pregcy. Late initiation of antiviral treatment was also associated with an increased risk for hospitalization. Although influenza is usually a self-limited disease, patients who develop complications are at increased risk of hospitalization, intensive care unit admission and death. Since preventive and early therapeutic measures should be prioritized in higher risk patients, identification of the risk factors for severe infection is important from a public health perspective. Risk factors for complications in pandemics may show some differences with regard to seasonal influenza. During the influenza A(H1N1)pmd09 pandemic, although many cases occurred in younger adults, the risk factors identified for severe infections and complications were similar to those for seasonal influenza, including chronic respiratory, renal, liver, and heart diseases. Aged patients, although less frequently affected, were also at higher risk. Obesity, and particularly morbid obesity (>40 body mass index) has been noted as a significant risk factor for severe disease in the 2009 influenza pandemic. Some interesting recent studies provide insights into the biological reasons behind the poor outcomes in morbidly obese patients. In terms of pregcy, the studies have shown contradictory results due to variations in methodology and medical care. However, it seems that pregcy, particularly during the third trimester, increases the risk of complications, and that early antiviral treatment is associated with improved outcomes. OBJECTIVE: To evaluate associations between laboratory-confirmed 2009 H1N1 influenza infection and obstetric and neonatal outcomes. STUDY DESIGN: A multicenter cohort study was performed comparing laboratory-confirmed cases of 2009 H1N1 infection during pregcy (N=142) with matched controls (N=710). Subanalysis was also performed comparing severely infected (hospitalized) women with controls. RESULT: No outcome differences were noted in comparing all women with H1N1 with controls. Women with severe infection had a higher incidence of delivering a small for gestational age (SGA) infant: 18.8% (6/32) versus 7.4% (52/707), adjusted odds ratio 2.35 (95% confidence interval 1.03, 5.36, P=0.02). Mean birth weight was 3013.0 g among severely infected women and 3223.3 g in controls (P=0.08), and incidence of preterm delivery was 25.0% (8/32) and 11.6% (82/710) (P=0.08), respectively. CONCLUSION: Pregt women with mild clinical illness secondary to 2009 H1N1 were not at a greater risk of adverse pregcy outcomes. However, severely infected women were more likely to deliver SGA infants.
Are long non coding RNAs as conserved in sequence as protein coding genes?
No. Most long non coding RNAs (lncRNAs) are under lower sequence constraints than protein-coding genes.
Experimental evidence suggests that half or more of the mammalian transcriptome consists of noncoding RNA. Noncoding RNAs are divided into short noncoding RNAs (including microRNAs) and long noncoding RNAs (lncRNAs). We defined complementary DNAs (cDNAs) lacking any positive-strand open reading frames (ORFs) longer than 30 amino acids, as well as cDNAs lacking any evidence of interspecies conservation of their longer-than-30-amino acid ORFs, as noncoding. We have identified 5446 lncRNA genes in the human genome from approximately 24,000 full-length cDNAs, using our new ORF-prediction pipeline. We combined them nonredundantly with lncRNAs from four published sources to derive 6736 lncRNA genes. In an effort to distinguish standalone and antisense lncRNA genes from database artifacts, we stratified our catalog of lncRNAs according to the distance between each lncRNA gene candidate and its nearest known protein-coding gene. We concurrently examined the protein-coding capacity of known genes overlapping with lncRNAs. Remarkably, 62% of known genes with "hypothetical protein" names actually lacked protein-coding capacity. This study has greatly expanded the known human lncRNA catalog, increased its accuracy through manual annotation of cDNA-to-genome alignments, and revealed that a large set of hypothetical-protein genes in GenBank lacks protein-coding capacity. In addition, we have developed, independently of existing NCBI tools, command-line programs with high-throughput ORF-finding and BLASTP-parsing functionality, suitable for future automated assessments of protein-coding capacity of novel transcripts. BACKGROUND: Long considered to be the building block of life, it is now apparent that protein is only one of many functional products generated by the eukaryotic genome. Indeed, more of the human genome is transcribed into noncoding sequence than into protein-coding sequence. Nevertheless, whilst we have developed a deep understanding of the relationships between evolutionary constraint and function for protein-coding sequence, little is known about these relationships for non-coding transcribed sequence. This dearth of information is partially attributable to a lack of established non-protein-coding RNA (ncRNA) orthologs among birds and mammals within sequence and expression databases. RESULTS: Here, we performed a multi-disciplinary study of four highly conserved and brain-expressed transcripts selected from a list of mouse long intergenic noncoding RNA (lncRNA) loci that generally show pronounced evolutionary constraint within their putative promoter regions and across exon-intron boundaries. We identify some of the first lncRNA orthologs present in birds (chicken), marsupial (opossum), and eutherian mammals (mouse), and investigate whether they exhibit conservation of brain expression. In contrast to conventional protein-coding genes, the sequences, transcriptional start sites, exon structures, and lengths for these non-coding genes are all highly variable. CONCLUSIONS: The biological relevance of lncRNAs would be highly questionable if they were limited to closely related phyla. Instead, their preservation across diverse amniotes, their apparent conservation in exon structure, and similarities in their pattern of brain expression during embryonic and early postnatal stages together indicate that these are functional RNA molecules, of which some have roles in vertebrate brain development. Large numbers of long RNAs with little or no protein-coding potential [long noncoding RNAs (lncRNAs)] are being identified in eukaryotes. In parallel, increasing data describing the expression profiles, molecular features and functions of individual lncRNAs in a variety of systems are accumulating. To enable the systematic compilation and updating of this information, we have developed a database (lncRNAdb) containing a comprehensive list of lncRNAs that have been shown to have, or to be associated with, biological functions in eukaryotes, as well as messenger RNAs that have regulatory roles. Each entry contains referenced information about the RNA, including sequences, structural information, genomic context, expression, subcellular localization, conservation, functional evidence and other relevant information. lncRNAdb can be searched by querying published RNA names and aliases, sequences, species and associated protein-coding genes, as well as terms contained in the annotations, such as the tissues in which the transcripts are expressed and associated diseases. In addition, lncRNAdb is linked to the UCSC Genome Browser for visualization and Noncoding RNA Expression Database (NRED) for expression information from a variety of sources. lncRNAdb provides a platform for the ongoing collation of the literature pertaining to lncRNAs and their association with other genomic elements. lncRNAdb can be accessed at: http://www.lncrnadb.org/. Thousands of long noncoding RNAs (lncRNAs) have been found in vertebrate animals, a few of which have known biological roles. To better understand the genomics and features of lncRNAs in invertebrates, we used available RNA-seq, poly(A)-site, and ribosome-mapping data to identify lncRNAs of Caenorhabditis elegans. We found 170 long intervening ncRNAs (lincRNAs), which had single- or multiexonic structures that did not overlap protein-coding transcripts, and about sixty antisense lncRNAs (ancRNAs), which were complementary to protein-coding transcripts. Compared to protein-coding genes, the lncRNA genes tended to be expressed in a stage-dependent manner. Approximately 25% of the newly identified lincRNAs showed little signal for sequence conservation and mapped antisense to clusters of endogenous siRNAs, as would be expected if they serve as templates and targets for these siRNAs. The other 75% tended to be more conserved and included lincRNAs with intriguing expression and sequence features associating them with processes such as dauer formation, male identity, sperm formation, and interaction with sperm-specific mRNAs. Our study provides a glimpse into the lncRNA content of a nonvertebrate animal and a resource for future studies of lncRNA function. BACKGROUND: The HOX gene clusters are thought to be highly conserved amongst mammals and other vertebrates, but the long non-coding RNAs have only been studied in detail in human and mouse. The sequencing of the kangaroo genome provides an opportunity to use comparative analyses to compare the HOX clusters of a mammal with a distinct body plan to those of other mammals. RESULTS: Here we report a comparative analysis of HOX gene clusters between an Australian marsupial of the kangaroo family and the eutherians. There was a strikingly high level of conservation of HOX gene sequence and structure and non-protein coding genes including the microRNAs miR-196a, miR-196b, miR-10a and miR-10b and the long non-coding RNAs HOTAIR, HOTAIRM1 and HOXA11AS that play critical roles in regulating gene expression and controlling development. By microRNA deep sequencing and comparative genomic analyses, two conserved microRNAs (miR-10a and miR-10b) were identified and one new candidate microRNA with typical hairpin precursor structure that is expressed in both fibroblasts and testes was found. The prediction of microRNA target analysis showed that several known microRNA targets, such as miR-10, miR-414 and miR-464, were found in the tammar HOX clusters. In addition, several novel and putative miRNAs were identified that originated from elsewhere in the tammar genome and that target the tammar HOXB and HOXD clusters. CONCLUSIONS: This study confirms that the emergence of known long non-coding RNAs in the HOX clusters clearly predate the marsupial-eutherian divergence 160 Ma ago. It also identified a new potentially functional microRNA as well as conserved miRNAs. These non-coding RNAs may participate in the regulation of HOX genes to influence the body plan of this marsupial. A large proportion of functional sequence within mammalian genomes falls outside protein-coding exons and can be transcribed into long RNAs. However, the roles in mammalian biology of long noncoding RNA (lncRNA) are not well understood. Few lncRNAs have experimentally determined roles, with some of these being lineage-specific. Determining the extent by which transcription of lncRNA loci is retained or lost across multiple evolutionary lineages is essential if we are to understand their contribution to mammalian biology and to lineage-specific traits. Here, we experimentally investigated the conservation of lncRNA expression among closely related rodent species, allowing the evolution of DNA sequence to be uncoupled from evolution of transcript expression. We generated total RNA (RNAseq) and H3K4me3-bound (ChIPseq) DNA data, and combined both to construct catalogues of transcripts expressed in the adult liver of Mus musculus domesticus (C57BL/6J), Mus musculus castaneus, and Rattus norvegicus. We estimated the rate of transcriptional turnover of lncRNAs and investigated the effects of their lineage-specific birth or death. LncRNA transcription showed considerably greater gain and loss during rodent evolution, compared with protein-coding genes. Nucleotide substitution rates were found to mirror the in vivo transcriptional conservation of intergenic lncRNAs between rodents: only the sequences of noncoding loci with conserved transcription were constrained. Finally, we found that lineage-specific intergenic lncRNAs appear to be associated with modestly elevated expression of genomically neighbouring protein-coding genes. Our findings show that nearly half of intergenic lncRNA loci have been gained or lost since the last common ancestor of mouse and rat, and they predict that such rapid transcriptional turnover contributes to the evolution of tissue- and lineage-specific gene expression. The human genome contains many thousands of long noncoding RNAs (lncRNAs). While several studies have demonstrated compelling biological and disease roles for individual examples, analytical and experimental approaches to investigate these genes have been hampered by the lack of comprehensive lncRNA annotation. Here, we present and analyze the most complete human lncRNA annotation to date, produced by the GENCODE consortium within the framework of the ENCODE project and comprising 9277 manually annotated genes producing 14,880 transcripts. Our analyses indicate that lncRNAs are generated through pathways similar to that of protein-coding genes, with similar histone-modification profiles, splicing signals, and exon/intron lengths. In contrast to protein-coding genes, however, lncRNAs display a striking bias toward two-exon transcripts, they are predomitly localized in the chromatin and nucleus, and a fraction appear to be preferentially processed into small RNAs. They are under stronger selective pressure than neutrally evolving sequences-particularly in their promoter regions, which display levels of selection comparable to protein-coding genes. Importantly, about one-third seem to have arisen within the primate lineage. Comprehensive analysis of their expression in multiple human organs and brain regions shows that lncRNAs are generally lower expressed than protein-coding genes, and display more tissue-specific expression patterns, with a large fraction of tissue-specific lncRNAs expressed in the brain. Expression correlation analysis indicates that lncRNAs show particularly striking positive correlation with the expression of antisense coding genes. This GENCODE annotation represents a valuable resource for future studies of lncRNAs. Tinkering with pre-existing genes has long been known as a major way to create new genes. Recently, however, motherless protein-coding genes have been found to have emerged de novo from ancestral non-coding DNAs. How these genes originated is not well addressed to date. Here we identified 24 hominoid-specific de novo protein-coding genes with precise origination timing in vertebrate phylogeny. Strand-specific RNA-Seq analyses were performed in five rhesus macaque tissues (liver, prefrontal cortex, skeletal muscle, adipose, and testis), which were then integrated with public transcriptome data from human, chimpanzee, and rhesus macaque. On the basis of comparing the RNA expression profiles in the three species, we found that most of the hominoid-specific de novo protein-coding genes encoded polyadenylated non-coding RNAs in rhesus macaque or chimpanzee with a similar transcript structure and correlated tissue expression profile. According to the rule of parsimony, the majority of these hominoid-specific de novo protein-coding genes appear to have acquired a regulated transcript structure and expression profile before acquiring coding potential. Interestingly, although the expression profile was largely correlated, the coding genes in human often showed higher transcriptional abundance than their non-coding counterparts in rhesus macaque. The major findings we report in this manuscript are robust and insensitive to the parameters used in the identification and analysis of de novo genes. Our results suggest that at least a portion of long non-coding RNAs, especially those with active and regulated transcription, may serve as a birth pool for protein-coding genes, which are then further optimized at the transcriptional level. Long noncoding RNAs (lncRNAs) have gained widespread attention in recent years as a potentially new and crucial layer of biological regulation. lncRNAs of all kinds have been implicated in a range of developmental processes and diseases, but knowledge of the mechanisms by which they act is still surprisingly limited, and claims that almost the entirety of the mammalian genome is transcribed into functional noncoding transcripts remain controversial. At the same time, a small number of well-studied lncRNAs have given us important clues about the biology of these molecules, and a few key functional and mechanistic themes have begun to emerge, although the robustness of these models and classification schemes remains to be seen. Here, we review the current state of knowledge of the lncRNA field, discussing what is known about the genomic contexts, biological functions, and mechanisms of action of lncRNAs. We also reflect on how the recent interest in lncRNAs is deeply rooted in biology's longstanding concern with the evolution and function of genomes. Novel, profound and unexpected roles of long non-coding RNAs (lncRNAs) are emerging in critical aspects of gene regulation. Thousands of lncRNAs have been recently discovered in a wide range of mammalian systems, related to development, epigenetics, cancer, brain function and hereditary disease. The structural biology of these lncRNAs presents a brave new RNA world, which may contain a diverse zoo of new architectures and mechanisms. While structural studies of lncRNAs are in their infancy, we describe existing structural data for lncRNAs, as well as crystallographic studies of other RNA machines and their implications for lncRNAs. We also discuss the importance of dynamics in RNA machine mechanism. Determining commonalities between lncRNA systems will help elucidate the evolution and mechanistic role of lncRNAs in disease, creating a structural framework necessary to pursue lncRNA-based therapeutics.
Mutation of which gene is implicated in the Brain-lung-thyroid syndrome?
Brain-lung-thyroid syndrome (BLTS) characterized by congenital hypothyroidism, respiratory distress syndrome, and benign hereditary chorea is caused by thyroid transcription factor 1 (NKX2-1/TTF1) mutations.
Thyroid transcription factor 1 (NKX2-1/TITF1) mutations cause brain-lung-thyroid syndrome, characterized by congenital hypothyroidism (CH), infant respiratory distress syndrome (IRDS) and benign hereditary chorea (BHC). The objectives of the present study were (i) detection of NKX2-1 mutations in patients with CH associated with pneumopathy and/or BHC, (ii) functional analysis of new mutations in vitro and (iii) description of the phenotypic spectrum of brain-lung-thyroid syndrome. We identified three new heterozygous missense mutations (L176V, P202L, Q210P), a splice site mutation (376-2A-->G), and one deletion of NKX2-1 at 14q13. Functional analysis of the three missense mutations revealed loss of transactivation capacity on the human thyroglobulin enhancer/promoter. Interestingly, we showed that deficient transcriptional activity of NKX2-1-P202L was completely rescued by cotransfected PAX8-WT, whereas the synergistic effect was abolished by L176V and Q210P. The clinical spectrum of 6 own and 40 published patients with NKX2-1 mutations ranged from the complete triad of brain-lung-thyroid syndrome (50%), brain and thyroid disease (30%), to isolated BHC (13%). Thyroid morphology was normal (55%) and compensated hypothyroidism occurred in 61%. Lung disease occurred in 54% of patients (IRDS at term 76%; recurrent pulmonary infections 24%). On follow-up, 20% developed severe chronic interstitial lung disease, and 16% died. In conclusion, we describe five new NKX2.1 mutations with, for the first time, complete rescue by PAX8 of the deficient transactivating capacity in one case. Additionally, our review shows that the majority of affected patients display neurological and/or thyroidal problems and that, although less frequent, lung disease is responsible for a considerable mortality. Mutations in NKX2-1 cause neurological, pulmonary, and thyroid hormone impairment. Recently, the disease was named brain-lung-thyroid syndrome. Here, we report three patients with brain-lung-thyroid syndrome. All patients were unable to walk until 24 months of age, and still have a staggering gait, without mental retardation. They have also had choreoathetosis since early infancy. Genetic analysis of NKX2-1 revealed a novel missense mutation (p.Val205Phe) in two patients who were cousins and their maternal families, and a novel 2.6-Mb deletion including NKX2-1 on chromosome 14 in the other patient. Congenital hypothyroidism was not detected on neonatal screening in the patient with the missense mutation, and frequent respiratory infections were observed in the patient with the deletion in NKX2-1. Oral levodopa did not improve the gait disturbance or involuntary movement. The results of (99m)Tc-ECD single-photon emission computed tomography (ECD-SPECT) analyzed using the easy Z-score imaging system showed decreased cerebral blood flow in the bilateral basal ganglia, especially in the caudate nuclei, in all three patients, but no brain magnetic resoce imaging (MRI) abnormalities. These brain nuclear image findings indicate that NKX2-1 haploinsufficiency causes dysfunction of the basal ganglia, especially the caudate nuclei, resulting in choreoathetosis and gait disturbance in this disease. BACKGROUND: NKX2.1 mutations have been identified in patients displaying complete or partial brain-lung-thyroid syndrome, which can include benign hereditary chorea (BHC), hypothyroidism and/or lung disease. AIMS AND METHODS: We evaluated the recently developed Multiplex Ligation-dependent Probe Amplification (MLPA) method to assess the relative copy number of genes. The goal was to determine if MLPA could improve, in addition to direct sequencing, the detection rate of NKX2.1 mutations in a phenotype-selected cohort of 24 patients affected by neurological, thyroid and/or pulmonary disorders. RESULTS: Direct sequencing revealed two heterozygous mutations. Using MLPA, we identified two further heterozygous NKX2.1 gene deletions. MLPA increased the detection rate by 50%. All patients with gene deletions identified were affected by BHC and congenital hypothyroidism. CONCLUSION: MLPA should be considered as a complementary tool in patients with partial or total brain-lung-thyroid syndrome when direct sequencing failed to identify NKX2.1 mutations. All patients with an NKX2.1 mutation had BHC and congenital hypothyroidism, emphasizing the high prevalence of these signs associated with defective NKX2.1 alleles. Brain-lung-thyroid syndrome (BLTS) characterized by congenital hypothyroidism, respiratory distress syndrome, and benign hereditary chorea is caused by thyroid transcription factor 1 (NKX2-1/TTF1) mutations. We report the clinical and molecular characteristics of four cases presenting with primary hypothyroidism, respiratory distress, and neurological disorder. Two of the four patients presenting with the triad of BLTS had NKX2-1 mutations, and one of these NKX2-1 [c.890_896del (p.Ala327Glyfs*52)] is a novel variant. The third patient without any identified NKX2-1 mutations was a carrier of mitochondrial mutation; this raises the possibility of mitochondrial mutations contributing to thyroid dysgenesis. Although rare, the triad of congenital hypothyroidism, neurological, and respiratory signs is highly suggestive of NKX2-1 anomalies. Screening for NKX2-1 mutations in patients with thyroid, lung, and neurological abnormalities will enable a unifying diagnosis and genetic counseling for the affected families. In addition, identification of an NKX2-1 defect would be helpful in allaying the concerns about inadequate thyroxine supplementation as the cause of neurological defects observed in some children with congenital hypothyroidism. AIM: Benign hereditary chorea is a domitly inherited, childhood-onset hyperkinetic movement disorder characterized by non-progressive chorea and variable degrees of thyroid and respiratory involvement. Loss-of-function mutations in NKX2.1, a gene vital to the normal development and function of the brain, lungs, and thyroid, have been identified in a number of individuals. METHOD: Clinical data from individuals with benign hereditary chorea identified through paediatric neurology services were collected in a standardized format. The NKX2.1 gene was analysed by Sanger sequencing, multiplex ligation-dependent probe amplification, and microarray analysis. RESULTS: Six of our cohort were female and four male, median age at assessment was 8 years 6 months (range 1 y 6 mo-18 y). We identified 10 probands with NKX2.1 mutations; nine of these mutations are novel (including two whole-gene deletions) and one has been previously reported. Of the 10 individuals, eight presented with muscle hypotonia and four had evidence of hypothyroidism or respiratory involvement. Only three out of the 10 individuals had the full triad of 'brain-lung-thyroid syndrome' symptoms. Additional clinical characteristics occurring in individual participants included growth hormone deficiency, pes cavus, kyphosis, duplex kidney, and obsessive-compulsive disorder. INTERPRETATION: Our data suggest that the neurological phenotype is prominent in this condition and that many patients with benign hereditary chorea do not have the classic triad of brain-lung-thyroid syndrome. The extended phenotype may include obsessive-compulsive disorder and skeletal abnormalities. OBJECTIVES: To verify the involvement of NKX2-1 gene in infants with brain-lung-thyroid (BLT) syndrome and hypothyroid phenotypes variable among congenital hypothyroidism (CH) or idiopathic mild hypothyroidism (IMH) of postnatal onset. METHODS: The candidates were selected by a case-finding approach in 130 CH and 53 IMH infants. The NKX2-1 gene was analyzed by direct sequencing and multiplex ligation-dependent probe amplification. The variants were studied in vitro, by expression analyses and luciferase bioassay. RESULTS: Four cases (3 CH and 1 IMH) consistent with BLT syndrome were identified. Two children were affected with respiratory distress and CH, but wild-type NKX2-1 gene. The remaining two presented choreic movements and no pulmonary involvement, but discrepant thyroid phenotypes: one had severe CH with lingual ectopy and the other one IMH with gland in situ. They were carriers of new de novo heterozygous frameshift mutations of NKX2-1 (c.177delG and c.153_166del14). The c.177delG leads to a prematurely truncated protein (p.H60TfsX11) with undetectable activity in vitro. The c.153_166del14 leads to the generation of an elongated aberrant protein (p.A52RfsX351) able to translocate into the nucleus, but completely inactive on a responsive promoter. CONCLUSIONS: Two novel heterozygous frameshift mutations of NKX2-1 were identified in 2 cases selected on the basis of a BLT-like phenotype among 183 hypothyroid infants. The atypical hypothyroid phenotypes of these 2 children (CH with lingual ectopy or IMH of postnatal onset) further expand the clinical spectrum that can be associated with NKX2-1 mutations.
What is clathrin?
Clathrin helps build small vesicles in order to safely transport molecules within and between cells.
Author information: (1)Department of Cell Biology and Physiology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA. [email protected] Author information: (1)Department of Cell Biology and Physiology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States of America. [email protected] Bacterial pathogens recruit clathrin upon interaction with host surface receptors during infection. Here, using three different infection models, we observed that host-pathogen interactions induce tyrosine phosphorylation of clathrin heavy chain. This modification was critical for recruitment of actin at bacteria-host adhesion sites during bacterial internalization or pedestal formation. At the bacterial interface, clathrin assembled to form coated pits of conventional size. Because such structures cannot internalize large particles such as bacteria, we propose that during infection, clathrin-coated pits serve as platforms to initiate actin rearrangements at bacteria-host adhesion sites. We then showed that the clathrin-actin interdependency is initiated by Dab2 and depends on the presence of clathrin light chain and its actin-binding partner Hip1R, and that the fully assembled machinery can recruit Myosin VI. Together, our study highlights a physiological role for clathrin heavy chain phosphorylation and reinforces the increasingly recognized function of clathrin in actin cytoskeletal organization in mammalian cells. The molecular mechanism responsible for capturing, sorting and retrieving vesicle membrane proteins following triggered exocytosis is not understood. Here we image the post-fusion release and then capture of a vesicle membrane protein, the vesicular acetylcholine transporter, from single vesicles in living neuroendocrine cells. We combine these measurements with super-resolution interferometric photo-activation localization microscopy and electron microscopy, and modelling to map the ometer-scale topography and architecture of the structures responsible for the transporter's capture following exocytosis. We show that after exocytosis, the transporter rapidly diffuses into the plasma membrane, but most travels only a short distance before it is locally captured over a dense network of membrane-resident clathrin-coated structures. We propose that the extreme density of these structures acts as a short-range diffusion trap. They quickly sequester diffusing vesicle material and limit its spread across the membrane. This system could provide a means for clathrin-mediated endocytosis to quickly recycle vesicle proteins in highly excitable cells. Exposure to oparticles during pregcy is a public concern, because oparticles may pass from the mother to the fetus across the placenta. The purpose of this study was to determine the possible translocation pathway of gold oparticles across the maternal-fetal barrier as well as the toxicity of intravenously administered gold oparticles to the placenta and fetus. Pregt ICR mice were intravenously injected with 0.01% of 20- and 50-nm gold oparticle solutions on the 16th and 17th days of gestation. There was no sign of toxic damage to the placentas as well as maternal and fetal organs of the mice treated with 20- and 50-nm gold oparticles. ICP-MS analysis demonstrated significant amounts of gold deposited in the maternal livers and placentas, but no detectable level of gold in the fetal organs. However, electron microscopy demonstrated an increase of endocytic vesicles in the cytoplasm of syncytiotrophoblasts and fetal endothelial cells in the maternal-fetal barrier of mice treated with gold oparticles. Clathrin immunohistochemistry and immunoblotting showed increased immunoreactivity of clathrin protein in the placental tissues of mice treated with 20- and 50-nm gold oparticles; clathrin immunopositivity was observed in syncytiotrophoblasts and fetal endothelial cells. In contrast, caveolin-1 immunopositivity was observed exclusively in the fetal endothelium. These findings suggested that intravenous administration of gold oparticles may upregulate clathrin- and caveolin-mediated endocytosis at the maternal-fetal barrier in mouse placenta. Clathrin-coated vesicles (CCVs) are formed at the plasma membrane and act as vectors for endocytosis. They also assemble at the trans-Golgi network (TGN), but their exact function at this organelle is unclear. Recent studies have examined the effects on vacuolar and secretory protein transport of knockout mutations of the adaptor protein 1 (AP1) μ-adaptin subunit AP1M, but these investigations do not clarify the situation. These mutations lead to the abrogation of multiple trafficking pathways at the TGN and cannot be used as evidence in favour of CCVs being agents for receptor-mediated export of vacuolar proteins out of the TGN. This transport process could just as easily occur through the maturation of the TGN into intermediate compartments that subsequently fuse with the vacuole. Author information: (1)Department of Cellular and Physiological Sciences, Faculty of Medicine, University of British Columbia, Vancouver, BC Canada V6T 1Z3. Electronic address: [email protected]. (2)Department of Cellular and Physiological Sciences, Faculty of Medicine, University of British Columbia, Vancouver, BC Canada V6T 1Z3. Electronic address: [email protected]. (3)Department of Cellular and Physiological Sciences, Faculty of Medicine, University of British Columbia, Vancouver, BC Canada V6T 1Z3. Electronic address: [email protected]. (4)Department of Radiology, College of Human Medicine, Michigan State University, Grand Rapids, MI 49503, USA. Electronic address: J'[email protected]. We reported the first small molecule inhibitors of the interaction between the clathrin N-terminal domain (TD) and endocyctic accessory proteins (i.e., clathrin inhibition1). Initial screening of a ∼17 000 small molecule ChemBioNet library identified 1. Screening of an existing in-house propriety library identified four substituted 1,8-napthalimides as ∼80-120 μM clathrin inhibitors. Focused library development gave 3-sulfo-N-(4-aminobenzyl)-1,8-naphthalimide, potassium salt (18, IC50 ≈ 18 μM). A second library targeting the 4-aminobenzyl moiety was developed, and four analogues displayed comparable activity (26, 27, 28, 34 with IC50 values of 22, 16, 15, and 15 μM respectively) with a further four (24, 25, 32, 33) more active than 18 with IC50 values of 10, 6.9, 12, and 10 μM, respectively. Docking studies rationalized the structure-activity relationship (SAR) with the biological data. 3-Sulfo-N-benzyl-1,8-naphthalimide, potassium salt (25) with an IC50 ≈ 6.9 μM, is the most potent clathrin terminal domain-amphiphysin inhibitor reported to date. Macromolecules gain access to the cytoplasm of eukaryotic cells using one of several ways of which clathrin-dependent endocytosis is the most researched. Although the mechanism of clathrin-mediated endocytosis is well understood in general, novel adaptor proteins that play various roles in ensuring specific regulation of the mentioned process are being discovered all the time. This review provides a detailed account of the mechanism of clathrin-mediated internalization of activated G protein-coupled receptors, as well as a description of the major proteins involved in this process. Clathrin-mediated endocytosis is a central and well-studied trafficking process in eukaryotic cells. How this process is initiated is likely to be a critical point in regulating endocytic activity spatially and temporally, but the underlying mechanisms are poorly understood. During the early stages of endocytosis three components-adaptor and accessory proteins, cargo, and lipids-come together at the plasma membrane to begin the formation of clathrin-coated vesicles. Although different models have been proposed, there is still no clear picture of how these three components cooperate to initiate endocytosis, which may indicate that there is some flexibility underlying this important event.
What are the main results of PRKAR1A Knockdown?
Suppression of protein kinase A regulatory subunit 1 alpha (PRKAR1A) has been proven to inhibit cholangiocarcinoma (CCA) cell growth and enhance apoptosis. Also, Knockdown of the cAMP-dependent protein kinase (PKA) Type Ialpha regulatory subunit in mouse oocytes disrupts meiotic arrest and results in meiotic spindle defects.
In mammalian oocytes, cyclic AMP-dependent protein kinase (PKA) is responsible for maintaining meiotic arrest. We examined the role of the predomit regulatory subunit, RIalpha in regulating PKA activity during mouse oocyte maturation by knocking down the protein levels using an RNA interference approach. In oocytes in which RIalpha protein was reduced to non-detectable levels, compensatory decreases were also observed in the RIIalpha and catalytic (Calpha) subunit levels. These oocytes resumed meiosis, despite culture under conditions that maintain elevated intracellular cAMP levels, suggesting that the remaining Calpha was not sufficient to maintain meiotic arrest. The resulting eggs, however, displayed meiotic spindle abnormalities and abnormal cleavage planes leading to extrusion of large polar bodies. These results demonstrate that RIalpha is required for regulating PKA activity in maturing oocytes and that compensatory upregulation of RII does not occur. Furthermore, we implicate PKA as a modulator of spindle morphology and function during meiosis. Suppression of protein kinase A regulatory subunit 1 alpha (PRKAR1A) has been proven to inhibit cholangiocarcinoma (CCA) cell growth and enhance apoptosis. In the present study, we aimed to determine synergistic and/or additive effects of chemotherapeutic agents, including protein kinase inhibitors (i.e. sorafenib, sunitinib, gefitinib, Met inhibitor) and conventional chemotherapeutic drugs (i.e. 5-fluorouracil, doxorubicin, paclitaxel, gemcitabine), in PRKARIA knockdown CCA cell lines. The results revealed that PRKAR1A suppressed CCA cell lines demonstrated enhanced sensitivity to some chemotherapeutic drugs when compared to control cells. Moreover, PRKAR1A knockdown in combination with either sorafenib or 5-fluorouracil increased apoptotic effects on CCA cell lines. Therefore, selective inhibition of PRKAR1A appears to enhance the growth inhibitory effects of chemotherapeutic drugs as well as induce apoptotic cell death. Our findings suggest that additional suppression of PRKAR1A expression may increase the efficacy of conventional CCA chemotherapeutic treatment. Clinical studies in CCA patients now need to be conducted. Carney complex (CNC) is a hereditary disease associating cardiac myxoma, spotty skin pigmentation and endocrine overactivity. CNC is caused by inactivating mutations in the PRKAR1A gene encoding PKA type I alpha regulatory subunit (RIα). Although PKA activity is enhanced in CNC, the mechanisms linking PKA dysregulation to endocrine tumorigenesis are poorly understood. In this study, we used Förster resoce energy transfer (FRET)-based sensors for cAMP and PKA activity to define the role of RIα in the spatiotemporal organization of the cAMP/PKA pathway. RIα knockdown in HEK293 cells increased basal as well as forskolin or prostaglandin E1 (PGE1)-stimulated total cellular PKA activity as reported by western blots of endogenous PKA targets and the FRET-based global PKA activity reporter, AKAR3. Using variants of AKAR3 targeted to subcellular compartments, we identified similar increases in the response to PGE1 in the cytoplasm and at the outer mitochondrial membrane. In contrast, at the plasma membrane, the response to PGE1 was decreased along with an increase in basal FRET ratio. These results were confirmed by western blot analysis of basal and PGE1-induced phosphorylation of membrane-associated vasodilator-stimulated phosphoprotein. Similar differences were observed between the cytoplasm and the plasma membrane in human adrenal cells carrying a RIα inactivating mutation. RIα inactivation also increased cAMP in the cytoplasm, at the outer mitochondrial membrane and at the plasma membrane, as reported by targeted versions of the cAMP indicator Epac1-camps. These results show that RIα inactivation leads to multiple, compartment-specific alterations of the cAMP/PKA pathway revealing new aspects of signaling dysregulation in tumorigenesis.
Is TENS machine effective in pain?
Transcutaneous electrical nerve stimulation is widely used in pain management
The hypoalgesic effect of transcutaneous electrical nerve stimulation (TENS) at 2 different frequencies was assessed under double-blind conditions using a standardised form of the submaximum effort tourniquet technique. For the purpose of pain induction, 32 healthy naive female subjects attended on 2 occasions, the first during which baseline data were obtained and the second during which the women were randomly allocated to 1 of 4 groups: Control, Placebo, TENS-1 (110 Hz) or TENS-2 (4 Hz). In the treatment groups, 2 hydrogel electrodes were positioned over Erb's point and lateral to C6 and C7 vertebral spines. A TENS machine was applied for 10 min before the cuff was inflated and remained on for the duration of the pain procedure (12 min). Pain was measured using visual analogue scales (VAS) and the McGill Pain Questionnaire (MPQ) to assess 'current pain intensity' and 'worst pain experienced', respectively. Analysis of VAS scores showed significant differences between groups (ANOVA, P = 0.02), with the TENS-2 group showing a greater hypoalgesic effect than the other groups. One-factor ANOVA showed no significant differences in MPQ scores between groups. The results of this study have provided evidence of the hypoalgesic effects of TENS upon experimental ischaemic pain which were found to be frequency specific with the lower frequency used here (4 Hz) demonstrating the only significant effect. Transcutaneous electrical nerve stimulation is widely used in pain management but its effectiveness depends on the stimulation being targeted appropriately. This article, the second in a two-part series, outlines how to set up and use a TENS machine to achieve the most effective results.
Is there any algorithm for enhancer identification from chromatin state?
yes
The chemical modification of histones at specific DNA regulatory elements is linked to the activation, inactivation and poising of genes. A number of tools exist to predict enhancers from chromatin modification maps, but their practical application is limited because they either (i) consider a smaller number of marks than those necessary to define the various enhancer classes or (ii) work with an excessive number of marks, which is experimentally unviable. We have developed a method for chromatin state detection using support vector machines in combination with genetic algorithm optimization, called ChromaGenSVM. ChromaGenSVM selects optimum combinations of specific histone epigenetic marks to predict enhancers. In an independent test, ChromaGenSVM recovered 88% of the experimentally supported enhancers in the pilot ENCODE region of interferon gamma-treated HeLa cells. Furthermore, ChromaGenSVM successfully combined the profiles of only five distinct methylation and acetylation marks from ChIP-seq libraries done in human CD4(+) T cells to predict ∼21,000 experimentally supported enhancers within 1.0 kb regions and with a precision of ∼90%, thereby improving previous predictions on the same dataset by 21%. The combined results indicate that ChromaGenSVM comfortably outperforms previously published methods and that enhancers are best predicted by specific combinations of histone methylation and acetylation marks. Transcriptional enhancers play critical roles in regulation of gene expression, but their identification in the eukaryotic genome has been challenging. Recently, it was shown that enhancers in the mammalian genome are associated with characteristic histone modification patterns, which have been increasingly exploited for enhancer identification. However, only a limited number of cell types or chromatin marks have previously been investigated for this purpose, leaving the question uswered whether there exists an optimal set of histone modifications for enhancer prediction in different cell types. Here, we address this issue by exploring genome-wide profiles of 24 histone modifications in two distinct human cell types, embryonic stem cells and lung fibroblasts. We developed a Random-Forest based algorithm, RFECS (Random Forest based Enhancer identification from Chromatin States) to integrate histone modification profiles for identification of enhancers, and used it to identify enhancers in a number of cell-types. We show that RFECS not only leads to more accurate and precise prediction of enhancers than previous methods, but also helps identify the most informative and robust set of three chromatin marks for enhancer prediction.
Which enzyme is targeted by the drug Imetelstat?
Imetelstat sodium (GRN163L), is a 13-mer oligonucleotide N3'→P5' thio-phosphoramidate lipid conjugate, which represents the latest generation of telomerase inhibitors targeting the template region of the human functional telomerase RNA subunit. In preclinical trials, this compound has been found to inhibit telomerase activity in multiple cancer cell lines, as well as in vivo xenograft mouse models.
Telomeres and telomerase play essential roles in the regulation of the lifespan of human cells. While normal human somatic cells do not or only transiently express telomerase and therefore shorten their telomeres with each cell division, most human cancer cells typically express high levels of telomerase and show unlimited cell proliferation. High telomerase expression allows cells to proliferate and expand long-term and therefore supports tumor growth. Owing to the high expression and its role, telomerase has become an attractive diagnostic and therapeutic cancer target. Imetelstat (GRN163L) is a potent and specific telomerase inhibitor and so far the only drug of its class in clinical trials. Here, we report on the structure and the mechanism of action of imetelstat as well as about the preclinical and clinical data and future prospects using imetelstat in cancer therapy. Nucleic acids analogues, i.e., oligonucleotide N3'-->P5' phosphoramidates and N3'-->P5' thio-phosphoramidates, containing 3'-amino-3'-deoxy nucleosides with various 2'-substituents were synthesized and extensively studied. These compounds resist nuclease hydrolysis and form stable duplexes with complementary native phosphodiester DNA and, particularly, RNA strands. An increase in duplexes' melting temperature, DeltaT(m), relative to their phosphodiester counterparts, reaches 2.2-4.0 degrees per modified nucleoside. 2'-OH- (RNA-like), 2'-O-Me-, and 2'-ribo-F-nucleoside substitutions result in the highest degree of duplex stabilization. Moreover, under close to physiological salt and pH conditions, the 2'-deoxy- and 2'-fluoro-phosphoramidate compounds form extremely stable triple-stranded complexes with either single- or double-stranded phosphodiester DNA oligonucleotides. Melting temperature, T(m), of these triplexes exceeds T(m) values for the isosequential phosphodiester counterparts by up to 35 degrees . 2'-Deoxy-N3'-->P5' phosphoramidates adopt RNA-like C3'-endo or N-type nucleoside sugar-ring conformations and hence can be used as stable RNA mimetics. Duplexes formed by 2'-deoxy phosphoramidates with complementary RNA strands are not substrates for RNase H-mediated cleavage in vitro. Oligonucleotide phosphoramidates and especially thio-phosphoramidates conjugated with lipid groups are cell-permeable and demonstrate high biological target specific activity in vitro. In vivo, these compounds show good bioavailability and efficient biodistribution to all major organs, while exerting acceptable toxicity at therapeutically relevant doses. Short oligonucleotide N3'-->P5' thio-phosphoramidate conjugated to 5'-palmitoyl group, designated as GRN163L (Imetelstat), was recently introduced as a potent human telomerase inhibitor. GRN163L is not an antisense agent; it is a direct competitive inhibitor of human telomerase, which directly binds to the active site of the enzyme and thus inhibits its activity. This compound is currently in multiple Phase-I and Phase-I/II clinical trials as potential broad-spectrum anticancer agent. Cancer stem cells (CSC) are rare drug-resistant cancer cell subsets proposed to be responsible for the maintece and recurrence of cancer and metastasis. Telomerase is constitutively active in both bulk tumor cell and CSC populations but has only limited expression in normal tissues. Thus, inhibition of telomerase has been shown to be a viable approach in controlling cancer growth in nonclinical studies and is currently in phase II clinical trials. In this study, we investigated the effects of imetelstat (GRN163L), a potent telomerase inhibitor, on both the bulk cancer cells and putative CSCs. When breast and pancreatic cancer cell lines were treated with imetelstat in vitro, telomerase activity in the bulk tumor cells and CSC subpopulations were inhibited. Additionally, imetelstat treatment reduced the CSC fractions present in the breast and pancreatic cell lines. In vitro treatment with imetelstat, but not control oligonucleotides, also reduced the proliferation and self-renewal potential of MCF7 mammospheres and resulted in cell death after <4 weeks of treatment. In vitro treatment of PANC1 cells showed reduced tumor engraftment in nude mice, concomitant with a reduction in the CSC levels. Differences between telomerase activity expression levels or telomere length of CSCs and bulk tumor cells in these cell lines did not correlate with the increased sensitivity of CSCs to imetelstat, suggesting a mechanism of action independent of telomere shortening for the effects of imetelstat on the CSC subpopulations. Our results suggest that imetelstat-mediated depletion of CSCs may offer an alternative mechanism by which telomerase inhibition may be exploited for cancer therapy. Specific information about how telomerase acts in vivo is necessary for understanding telomere dynamics in human tumor cells. Our results imply that, under homeostatic telomere length-maintece conditions, only one molecule of telomerase acts at each telomere during every cell division and processively adds ∼60 nt to each end. In contrast, multiple molecules of telomerase act at each telomere when telomeres are elongating (nonequilibrium conditions). Telomerase extension is less processive during the first few weeks following the reversal of long-term treatment with the telomerase inhibitor Imetelstat (GRN163L), a time when Cajal bodies fail to deliver telomerase RNA to telomeres. This result implies that processing of telomerase by Cajal bodies may affect its processivity. Overexpressed telomerase is also less processive than the endogenously expressed telomerase. These findings reveal two major distinct extension modes adopted by telomerase in vivo. Breast cancer is a progressive and potentially fatal disease that affects women of all ages. Like all progressive diseases, early and reliable diagnosis is the key for successful treatment and annihilation. Biomarkers serve as indicators of pathological, physiological, or pharmacological processes. Her2/neu, CA15.3, estrogen receptor (ER), progesterone receptor (PR), and cytokeratins are biomarkers that have been approved by the Food and Drug Administration for disease diagnosis, prognosis, and therapy selection. The structural and functional complexity of protein biomarkers and the heterogeneity of the breast cancer pathology present challenges to the scientific community. Here we review estrogen receptor-related putative breast cancer biomarkers, including those of putative breast cancer stem cells, a minor population of estrogen receptor negative tumor cells that retain the stem cell property of self-renewal. We also review a few promising cytoskeleton targets for ER alpha negative breast cancer. Recently, there has been renewed interest in the role of tumor stem cells (TSCs) in tumorigenesis, chemoresistance, and relapse of maligt tumors including osteosarcoma. The potential exists to improve osteosarcoma treatment through characterization of TSCs and identification of therapeutic targets. Using transcriptome, proteome, immunophenotyping for cell-surface markers, and bioinformatic analyses, heterogeneous expression of previously reported TSC or osteosarcoma markers, such as CD133, nestin, POU5F1 (OCT3/4), NANOG, SOX2, and aldehyde dehydrogenase, among others, was observed in vitro. However, consistently significantly lower CD326, CD24, CD44, and higher ABCG2 expression in TSC-enriched as compared with un-enriched osteosarcoma cultures was observed. In addition, consistently higher CBX3 expression in TSC-enriched osteosarcoma cultures was identified. ABCA5 was identified as a putative biomarker of TSCs and/or osteosarcoma. Lastly, in a high-throughput screen we identified epigenetic (5-azacytidine), anti-microtubule (vincristine), and anti-telomerase (3,11-difluoro-6,8,13-trimethyl- 8H-quino [4,3,2-kl] acridinium methosulfate; RHPS4)-targeted therapeutic agents as candidates for TSC ablation in osteosarcoma. INTRODUCTION: Physiologically relevant pre-clinical ex vivo models recapitulating CNS tumor micro-environmental complexity will aid development of biologically-targeted agents. We present comprehensive characterization of tumor aggregates generated using the 3D Rotary Cell Culture System (RCCS). METHODS: CNS cancer cell lines were grown in conventional 2D cultures and the RCCS and comparison with a cohort of 53 pediatric high grade gliomas conducted by genome wide gene expression and microRNA arrays, coupled with immunohistochemistry, ex vivo magnetic resoce spectroscopy and drug sensitivity evaluation using the histone deacetylase inhibitor, Vorinostat. RESULTS: Macroscopic RCCS aggregates recapitulated the heterogeneous morphology of brain tumors with a distinct proliferating rim, necrotic core and oxygen tension gradient. Gene expression and microRNA analyses revealed significant differences with 3D expression intermediate to 2D cultures and primary brain tumors. Metabolic profiling revealed differential profiles, with an increase in tumor specific metabolites in 3D. To evaluate the potential of the RCCS as a drug testing tool, we determined the efficacy of Vorinostat against aggregates of U87 and KNS42 glioblastoma cells. Both lines demonstrated markedly reduced sensitivity when assaying in 3D culture conditions compared to classical 2D drug screen approaches. CONCLUSIONS: Our comprehensive characterization demonstrates that 3D RCCS culture of high grade brain tumor cells has profound effects on the genetic, epigenetic and metabolic profiles of cultured cells, with these cells residing as an intermediate phenotype between that of 2D cultures and primary tumors. There is a discrepancy between 2D culture and tumor molecular profiles, and RCCS partially re-capitulates tissue specific features, allowing drug testing in a more relevant ex vivo system. Many current chemotherapies function by damaging genomic DNA in rapidly dividing cells ultimately leading to cell death. This therapeutic approach differentially targets cancer cells that generally display rapid cell division compared to normal tissue cells. However, although these treatments are initially effective in arresting tumor growth and reducing tumor burden, resistance and disease progression eventually occur. A major mechanism underlying this resistance is increased levels of cellular DNA repair. Most cells have complex mechanisms in place to repair DNA damage that occurs due to environmental exposures or normal metabolic processes. These systems, initially overwhelmed when faced with chemotherapy induced DNA damage, become more efficient under constant selective pressure and as a result chemotherapies become less effective. Thus, inhibiting DNA repair pathways using target specific small molecule inhibitors may overcome cellular resistance to DNA damaging chemotherapies. Non-homologous end joining a major mechanism for the repair of double-strand breaks (DSB) in DNA is regulated in part by the serine/threonine kinase, DNA dependent protein kinase (DNA-PK). The DNA-PK holoenzyme acts as a scaffold protein tethering broken DNA ends and recruiting other repair molecules. It also has enzymatic activity that may be involved in DNA damage signaling. Because of its' central role in repair of DSBs, DNA-PK has been the focus of a number of small molecule studies. In these studies specific DNA-PK inhibitors have shown efficacy in synergizing chemotherapies in vitro. However, compounds currently known to specifically inhibit DNA-PK are limited by poor pharmacokinetics: these compounds have poor solubility and have high metabolic lability in vivo leading to short serum half-lives. Future improvement in DNA-PK inhibition will likely be achieved by designing new molecules based on the recently reported crystallographic structure of DNA-PK. Computer based drug design will not only assist in identifying novel functional moieties to replace the metabolically labile morpholino group but will also facilitate the design of molecules to target the DNA-PKcs/Ku80 interface or one of the autophosphorylation sites. Evidence continues to accumulate showing that tumors contain a minority population of cells responsible for tumor initiation, growth, and recurrence. These are termed "cancer stem cells" (CSCs). Functional assays have identified the self-renewal and tumor-initiation capabilities of CSCs. Moreover, recent studies have revealed that these CSCs is responsible for chemotherapy resistance within a tumor. Several mechanisms of chemoresistance have been proposed, including increased Wnt/β-catenin and Notch signaling, as well as high expression levels of adenosine triphosphate-binding cassette transporters, an active DNA repair capacity, and slow rate of self-renewal. Nanoscale drug-delivery systems, which transport therapeutically active molecules, prolong circulation, and improve biodistribution in the body, may allow more effective and specific therapies to address the challenges posed by CSCs. In particular, some ovehicles are being exploited for selective drug delivery to CSCs and show promising results. In this review, we highlight the mechanisms of drug resistance and the novel strategies using oscale drugs to eliminate CSCs. The emergence of diseases associated with telomere dysfunction, including AIDS, aplastic anemia and pulmonary fibrosis, has bolstered interest in telomerase activators. We report identification of a new small molecule activator, GRN510, with activity ex vivo and in vivo. Using a novel mouse model, we tested the potential of GRN510 to limit fibrosis induced by bleomycin in mTERT heterozygous mice. Treatment with GRN510 at 10 mg/kg/day activated telomerase 2-4 fold both in hematopoietic progenitors ex vivo and in bone marrow and lung tissue in vivo, respectively. Telomerase activation was countered by co-treatment with Imetelstat (GRN163L), a potent telomerase inhibitor. In this model of bleomycin-induced fibrosis, treatment with GRN510 suppressed the development of fibrosis and accumulation of senescent cells in the lung via a mechanism dependent upon telomerase activation. Treatment of small airway epithelial cells (SAEC) or lung fibroblasts ex vivo with GRN510 revealed telomerase activating and replicative lifespan promoting effects only in the SAEC, suggesting that the mechanism accounting for the protective effects of GRN510 against induced lung fibrosis involves specific types of lung cells. Together, these results support the use of small molecule activators of telomerase in therapies to treat idiopathic pulmonary fibrosis. Telomerase comprises a reverse transcriptase and an internal RNA template that maintains telomeres in many eukaryotes, and it is a well-validated cancer target. However, there is a dearth of small molecules with efficacy against human telomerase in vivo. We developed a surrogate yeast high-throughput assay to identify human telomerase inhibitors. The reversibility of growth arrest induced by active human telomerase was assessed against a library of 678 compounds preselected for bioactivity in S. cerevisiae. Four of eight compounds identified reproducibly restored growth to strains expressing active human telomerase, and three of these four compounds also specifically inhibited purified human telomerase in vitro. These compounds represent probes for human telomerase function, and potential entry points for development of lead compounds against telomerase-positive cancers. Telomerase is a cellular ribonucleoprotein reverse transcriptase that plays a crucial role in telomere maintece. This enzyme is expressed in approximately 90% of human tumors, but not in the majority of normal somatic cells. imetelstat sodium (GRN163L), is a 13-mer oligonucleotide N3'→P5' thio-phosphoramidate lipid conjugate, which represents the latest generation of telomerase inhibitors targeting the template region of the human functional telomerase RNA (hTR) subunit. In preclinical trials, this compound has been found to inhibit telomerase activity in multiple cancer cell lines, as well as in vivo xenograft mouse models. Currently, GRN163L is being investigated in several clinical trials, including a phase II human non‑small cell lung cancer clinical trial, in a maintece setting following standard doublet chemotherapy. In addition to the inhibition of telomerase activity in cancer cell lines, GRN163L causes morphological cell rounding changes, independent of hTR expression or telomere length. This leads to the loss of cell adhesion properties; however, the mechanism underlying this effect is not yet fully understood. In the present study, we observed that GRN163L treatment leads to the loss of adhesion in A549 lung cancer cells, due to decreased E-cadherin expression, leading to the disruption of the cytoskeleton through the alteration of actin, tubulin and intermediate filament organization. Consequently, the less adherent cancer cells initially cease to proliferate and are arrested in the G1 phase of the cell cycle, accompanied by decreased matrix metalloproteinase-2 (MMP-2) expression. These effects of GRN163L are independent of its telomerase catalytic activity and may increase the therapeutic efficacy of GRN163L by decreasing the adhesion, proliferation and metastatic potential of cancer cells in vivo. Tumor relapse after radiotherapy is a great concern in the treatment of high-grade gliomas. Inhibition of the PI3-kinase/AKT pathway is known to radiosensitize cancer cells and to delay their DNA repair after irradiation. In this study, we show that the radiosensitization of CB193 and T98G, two high-grade glioma cell lines, by the PI3K inhibitor LY294002, correlates with the induction of G1 and G2/M arrest, but is inconsistently linked to a delayed DNA double-strand break (DSBs) repair. The PI3K/AKT pathway has been shown to activate radioprotective factors such as telomerase, whose inhibition may contribute to the radiosensitization of cancer cells. However, we show that radiation upregulates telomerase activity in LY-294002-treated glioma cells as well as untreated controls, demonstrating a PI3K/AKT-independent pathway of telomerase activation. Our study suggests that radiosensitizing strategies based on PI3-kinase inhibition in high-grade gliomas may be optimized by additional treatments targeting either telomerase activity or telomere maintece. In the era of new and mostly effective therapeutic protocols, multiple myeloma still tends to be a hard-to-treat hematologic cancer. This hallmark of the disease is in fact a sequel to drug resistant phenotypes persisting initially or emerging in the course of treatment. Furthermore, the heterogeneous nature of multiple myeloma makes treating patients with the same drug challenging because finding a drugable oncogenic process common to all patients is not yet feasible, while our current knowledge of genetic/epigenetic basis of multiple myeloma pathogenesis is outstanding. Nonetheless, bone marrow microenvironment components are well known as playing critical roles in myeloma tumor cell survival and environment-mediated drug resistance happening most possibly in all myeloma patients. Generally speaking, however; real mechanisms underlying drug resistance in multiple myeloma are not completely understood. The present review will discuss the latest findings and concepts in this regard. It reviews the association of important chromosomal translocations, oncogenes (e.g. TP53) mutations and deranged signaling pathways (e.g. NFκB) with drug response in clinical and experimental investigations. It will also highlight how bone marrow microenvironment signals (Wnt, Notch) and myeloma cancer stem cells could contribute to drug resistance in multiple myeloma.
Which interleukins are inhibited by Dupilumab?
Dupilumab, a fully human monoclonal antibody that blocks interleukin-4 and interleukin-13, has shown efficacy in patients with asthma and elevated eosinophil levels.
PURPOSE OF REVIEW: A small proportion of patients with asthma have severe disease characterized by persistent airflow obstruction, airway hyperresponsiveness and eosinophilic airway inflammation. This review focuses on the clinical efficacy of inhibiting T helper 2-cytokine-mediated inflammatory responses using monoclonal antibodies directed against immunoglobulin E (IgE), interleukin (IL)-5, and IL-4/IL-13 in patients with severe refractory asthma. RECENT FINDINGS: The heterogeneity of airway inflammation in severe asthma has led to the recognition of multiple pathophysiologically distinct severe asthma endotypes. Biomarkers are being developed and evaluated to identify these endotypes and to guide the use of specific biologics in the appropriate patients who remain uncontrolled on high doses of inhaled corticosteroids and long-acting bronchodilators or oral corticosteroids. Examples include the efficacy of omalizumab in patients with severe refractory atopic asthma characterized by raised serum total IgE, mepolizumab, reslizumab, and benralizumab in patients with recurrent eosinophilic exacerbations characterized by blood and sputum eosinophilia despite high doses of corticosteroids, and lebrikizumab, pitrakinra, dupilumab, and tralokinumab that target the IL-4/IL-13 signalling pathways in patients with eosinophilic asthma or raised serum periostin. SUMMARY: In severe refractory asthma, both an understanding of the underlying pathophysiologic mechanisms driving airway inflammation and the identification of appropriate biomarkers in individual patients are critical in guiding the use of biologics and monoclonal antibodies that target the specific pathological processes. Simultaneously with the steady progress towards a better knowledge of the pathobiology of asthma, the potential usefulness of anticytokine therapies is emerging as one of the key concepts in the newly developing treatments of this widespread airway disease. In particular, given the key role played by interleukin (IL)-4 and IL-13 in the pathophysiology of the most typical aspects of asthma, such as chronic airway inflammation, tissue remodeling, and bronchial hyperresponsiveness, these pleiotropic cytokines are now considered as suitable therapeutic targets. Among the recently developed antiasthma biologic drugs, the monoclonal antibody dupilumab is very promising because of its ability to inhibit the biological effects of both IL-4 and IL-13. Indeed, dupilumab prevents IL-4/13 interactions with the α-subunit of the IL-4 receptor complex. A recent trial showed that in patients with difficult-to-control asthma, dupilumab can markedly decrease asthma exacerbations and improve respiratory symptoms and lung function; these effects were paralleled by significant reductions in T-helper 2-associated inflammatory biomarkers. However, further larger and longer trials are required to extend and validate these preliminary results, and also to carefully study the safety and tolerability profile of dupilumab. BACKGROUND: Severe atopic dermatitis (AD) has a high unmet need for effective and safe therapeutics. In early-phase trials, dupilumab, a fully human mAb targeting IL-4 receptor α, markedly improved disease activity, but the effect of IL-4/IL-13 blockade on AD at the molecular level has not been characterized. OBJECTIVES: We sought to evaluate dupilumab modulation of the AD molecular signature. METHODS: We performed transcriptomic analyses of pretreatment and posttreatment skin biopsy specimens from patients with moderate-to-severe AD treated weekly with 150 or 300 mg of dupilumab or placebo. RESULTS: Exacerbation of the AD transcriptome was observed in placebo-treated patients. Dupilumab improved the AD signature in a dose-dependent manner. Expression of genes upregulated in AD lesions decreased in patients treated with dupilumab by 26% (95% CI, 21% to 32%) and 65% (95% CI, 60% to 71%) for treatment with 150 and 300 mg, respectively. Genes downregulated in AD lesions increased by 21% (95% CI, 16% to 27%) and 32% (95% CI, 26% to 37%) with dupilumab (150 and 300 mg, respectively). The molecular changes paralleled improvements in clinical scores. A dupilumab treatment signature of 821 probes (>2-fold change, P < .05) significantly modulated in the 300-mg dupilumab group at week 4 compared with baseline was identified in this sample set. Significant (P < .05) decreases in mRNA expression of genes related to hyperplasia (K16 and MKI67), T cells, and dendritic cells (CD1b and CD1c) and potent inhibition of TH2-associated chemokines (CCL17, CCL18, CCL22, and CCL26) were noted without significant modulation of TH1-associated genes (IFNG). CONCLUSIONS: This is the first report showing rapid improvement of the AD molecular signature with targeted anti-IL-4 receptor α therapy. These data suggest that IL-4 and IL-13 drive a complex, TH2-centered inflammatory axis in patients with AD. An update to the atopic dermatitis (AD) practice parameter was published in 2013 using an established grading system for determining category of evidence and strength of recommendation. Since the previous update in 2004, a number of seminal observations regarding skin barrier and immune dysregulation in AD have been made with important therapeutic implications. A key addition to the treatment algorithm based on our understanding that normal-appearing skin in patients with AD is not normal is proactive therapy. Studies with both topical steroids and a topical calcineurin inhibitor have shown that in patients with relapsing AD, if they are able to clear or almost clear their eczema, then twice-weekly proactive treatment of normal-appearing skin that tends to flare leads to better disease control. For difficult-to-manage patients, the value of wet wrap therapy is reaffirmed in the practice parameter update. In addition, allergen immunotherapy is now a consideration in select patients with AD and aeroallergen sensitivity. Beyond the practice parameter, novel approaches to filaggrin deficiency are being evaluated. With respect to immune dysregulation, dupilumab, a fully human monoclonal antibody directed at the IL-4 receptor alpha subunit was recently shown to be effective in treating adults with moderate-to-severe AD. Currently the only approved drug available for the systemic therapy of atopic dermatitis is cyclosporine; however, based on current data from published studies, azathioprine, methotrexate, and mycophenolate mofetil or mycophenolic acid can be administered off-label. Some biologics on the market that have been approved for other indications (ustekinumab, rituximab, tocilizumab) have been successfully used in a few patients with atopic dermatitis. The world's first prospective controlled studies with the biologic human anti-IL4R antibody dupilumab for the indication "atopic dermatitis" were published in 2014. These motivated (1) to extend the studies to dupilumab and (2) to clinically test antagonization of other target molecules of TH2 polarized, atopic inflammation, e.g., IL-13, IL-31, IL-22, TSLP, and CRTH2. A number of clinical trials are currently recruiting in this area and will provide interesting new insights for future therapeutic approaches in atopic dermatitis.
Which human genes are more commonly related to craniosynostosis?
The genes that are most commonly linked to craniosynostoses are the members of the Fibroblast Growth Factor Receptor family FGFR3 and to a lesser extent FGFR1 and FGFR2. Some variants of the disease have been associated with the triplication of the MSX2 gene and mutations in NELL-1. NELL-1 is being regulated bu RUNX2, which has also been associated to cases of craniosynostosis. Other genes reported to have a role in the development of the disease are RECQL4, TWIST, SOX6 and GNAS.
Recently, a unique Pro250Arg point mutation in fibroblast growth factor receptor 3 (FGFR3) was reported in 61 individuals with coronal craniosynostosis from 20 unrelated families [Muenke et al. (1997): Am J Hum Genet 60:555-564]. The discovery of this apparently common mutation has resulted in the definition of a recognizable syndrome, through analysis of subtle clinical findings in families who were previously thought to have a variety of other craniosynostosis syndromes. Previous diagnoses in some of these families have included Jackson-Weiss, Saethre-Chotzen, and Pfeiffer syndromes, as well as Adelaide-type craniosynostosis and brachydactyly-craniosynostosis syndrome [Adès et al. (1994): Am J Med Genet 51:121-130; von Gernet et al. (1996): Am J Med Genet 63:177-184; Reardon et al. (1997): J Med Genet 34:632-636; Bellus et al. (1996): Nat Genet 14:174-176; Hollaway et al. (1995): Hum Mol Genet 4:681-683; Glass et al. (1994): Clin Dysmorphol 3:215-223]. There appears to be a need to further delineate the phenotype associated with this common mutation in FGFR3. We compare the clinical characteristics of previously reported cases of this unique Pro250Arg mutation with those of two additional families and suggest that this syndrome with a unique mutational basis be designated coronal craniosynostosis with brachydactyly and carpal/tarsal coalition due to Pro250Arg mutation in FGFR3 gene, to emphasize the distinctive findings which may be present even in the absence of coronal craniosynostosis. Throughout its complex morphogenesis, the vertebrate skull must at once protect the brain and expand to accommodate its growth. A key structural adaptation that allows this dual role is the separation of the bony plates of the skull with sutures, fibrous joints that serve as growth centers and allow the calvarial bones to expand as the brain enlarges. Craniosynostosis, the premature fusion of one or more calvarial bones with consequent abnormalities in skull shape, is a common developmental anomaly that disrupts this process. We found previously that a single amino acid substitution in the homeodomain of the human MSX2 gene is associated with the autosomal domit disorder craniosynostosis, Boston type. This mutation enhances the affinity of Msx2 for its target sequence, suggesting that the mutation acts by a domit positive mechanism. Consistent with this prediction, we showed that general overexpression of Msx2 under the control of the broadly expressed CMV promoter causes the calvarial bones to invade the sagittal suture. Here we use tissue-specific overexpression of Msx2 within the calvarial sutures to address the developmental mechanisms of craniosynostosis and skull morphogenesis. We demonstrate that a segment of the Msx2 promoter directs reporter gene expression to subsets of cells within the sutures. In late embryonic and neonatal stages, this promoter is expressed in undifferentiated mesenchymal cells medial to the growing bone. By P4, promoter activity is reduced in the suture, exhibiting a punctate pattern in undifferentiated osteoblastic cells in the outer margin of the osteogenic front. Overexpression of Msx2 under the control of this promoter is sufficient to enhance parietal bone growth into the sagittal suture by P6. This phenotype is preceded by an increase in both the number and the BrdU labeling of osteoblastic cells in the osteogenic fronts of the calvarial bones. These findings suggest that an important early event in MSX2-mediated craniosynostosis in humans is a transient retardation of osteogenic cell differentiation in the suture and a consequent increase in the pool of osteogenic cells. A unique Pro250Arg mutation in fibroblast growth factor receptor 3 (FGFR3) was recently found in patients with non-syndromic craniosynostosis. We studied 18 Taiwan Chinese patients with various types of craniosynostosis to evaluate if this mutation is also prevalent in the Chinese population. Genomic DNA was analysed by polymerase chain reaction based restriction analysis and direct sequencing to identify the Pro250Arg mutation in FGFR3. Five (28%) of 18 probands were heterozygous for the Pro250Arg mutation. Only those patients with coronal synostosis carried this mutation. CONCLUSION: Our findings suggest that all patients with coronal synostosis should be examined for this unique mutation. Mutations in the fibroblast growth factor receptor 1, 2 and 3 (FGFR1, -2 and -3) and TWIST genes have been identified in several syndromic forms of craniosynostosis. There remains, however, a significant number of patients with non-syndromic craniosynostosis in whom no genetic cause can be identified. We describe a novel heterozygous mutation of FGFR2 (943G --> T, encoding the amino acid substitution Ala315Ser) in a girl with non-syndromic unicoronal craniosynostosis. The mutation is also present in her mother and her maternal grandfather who have mild facial asymmetry but do not have craniosynostosis. None of these individuals has the Crouzonoid appearance typically associated with FGFR2 mutations. However, the obstetric history revealed that the proband was in persistent breech presentation in utero and was delivered by Caesarean section, at which time compression of the skull was apparent. We propose that this particular FGFR2 mutation only confers a predisposition to craniosynostosis and that an additional environmental insult (in this case foetal head constraint associated with breech position) is necessary for craniosynostosis to occur. To our knowledge, this is the first report of an interaction between a weakly pathogenic mutation and intrauterine constraint, leading to craniosynostosis. Recently, the substitution of proline 250 by arginine in the fibroblast growth factor receptor 3 (FGFR3) gene, has been identified in patients with craniosynostosis and defines a new syndrome on a molecular basis. We report a 1-year-1-month-old female with bilateral coronal craniosynostosis who had the P250R mutation in FGFR3 gene detected by DNA sequencing. She had brachycephaly, temporal bossing, high and flat forehead, hypertelorism, mild proptosis, low set ears and no digital abnormalities. She underwent surgical repair at 7 months and her cosmetic problems were improved. Her development was normal up to 13 months of age. DNA analysis from her parents showed that her father had the same mutation. The phenotypes of the P250R mutation in the FGFR3 syndrome are variable even within the same family, but main characteristic clinical features are follows, 1) lateral or bilateral coronal craniosynostosis, 2) mild hand and foot anomalies, and 3) sensory deafness. In FGFR3 syndrome the diagnosis of P250R mutation by polymerase chain reaction (PCR) is very easy and important for early diagnosis and genetic counseling. Apert (Ap) syndrome is characterized by premature cranial suture ossification caused by fibroblast growth factor receptor 2 (FGFR-2) mutations. We studied the role of cadherins and signaling events in the phenotypic alterations induced by the Ap FGFR-2 S252W mutation in mutant immortalized fetal human calvaria osteoblasts. The FGFR-2 mutation caused increased expression of the osteoblast markers alkaline phosphatase (ALP), type 1 collagen (COLIA1), and osteocalcin (OC) in long-term culture. The mutation also increased cell-cell aggregation, which was suppressed by specific neutralizing anti-N- and anti-E-cadherin antibodies. Mutant osteoblasts showed increased N- and E-cadherin, but not N-cell adhesion molecule (N-CAM) messenger RNA (mRNA) and protein levels. This was confirmed in vivo by the abundant immunoreactive N- and E-cadherins in preosteoblasts in the Ap suture whereas N-CAM and alpha- and beta-catenins were unaffected. Neutralizing anti-N-cadherin antibody or N-cadherin antisense (AS) oligonucleotides but not anti-E-cadherin antibody or AS reduced ALP activity as well as ALP, COLIA1, and OC mRNA overexpression in mutant osteoblasts. Analysis of signal transduction revealed increased phospholipase Cgamma (PLCgamma) and protein kinase Calpha (PKCalpha) phosphorylation and increased PKC activity in mutant cells in basal conditions. Inhibition of PKC by calphostin C or the PKCalpha-specific inhibitor Gö6976 suppressed the increased N-cadherin mRNA and protein levels as well as the overexpression of ALP, COLIA1, and OC mRNA in mutant cells. Thus, N-cadherin plays a role in the activation of osteoblast differentiation marker genes in mutant osteoblasts and PKCalpha signaling appears to be involved in the increased N-cadherin and osteoblast gene expression induced by the S252W FGFR-2 mutation in human osteoblasts. Familial craniosynostosis due to Pro250Arg mutation in the fibroblast growth factor receptor 3 gene. Most mutations in Crouzon, Pfeiffer, and Apert syndromes are in the extracellular, third immunoglobulin-like domain and adjacent linker regions (exons IIIa and IIIc) of the fibroblast growth factor receptor 2 (FGFR2) gene. Using the published primers for PCR, a patient with Crouzon syndrome was found to be homozygous for a mutation that results in a Q289P amino acid substitution in FGFR2. Two additional patients; one with Apert syndrome and P253R mutation, the other with Pfeiffer syndrome and S267P mutation, also appeared to be homozygous. Using a new primer located 146 bp 5' of exon IIIa for PCR followed by sequencing revealed an A to G polymorphism at -62 [corrected] position of exon IIIa. All three patients were heterozygous for both the mutation and the polymorphism. These results indicate that the polymorphism and the mutation are not on the same chromosome. The single nucleotide polymorphism is located at the second to the last base of the 3' end of the published primer. This primer mismatch caused the failure of amplification of the normal chromosome and thus, the apparent homozygosity. The frequency of this novel polymorphism was determined to be 0.03 by studying 326 chromosomes from the general population. We propose that a new primer should be used for mutational analysis of exon IIIa of FGFR2 to avoid misdiagnosis caused by primer mismatch. A unique Pro250Arg point mutation in fibroblast growth factor receptor 3 (FGFR3) was initially reported by Bellus et al. [1996: Nat Genet 14:174-176] and the phenotype subsequently by Muenke et al. [1997: Am J Hum Genet 60:555-564], Reardon et al. [1997: J Med Genet 34:632-636], and Graham et al. [1998: Am J Med Genet 77:322-329]. These authors emphasized the pleiotropic nature of this form of coronal craniosynostosis, including brachydactyly with carpal and/or tarsal coalitions, with other anomalies at lower frequency. We report on a family with autosomal domit coronal synostosis, segmentation and fusion anomalies of the vertebra and ribs, and Sprengel shoulder due to the Pro250Arg mutation. We also report a single case with an identical phenotype without the mutation. One of the genes involved in craniosynostosis syndromes is the fibroblast growth factor receptor 2 (FGFR2) gene, a tyrosine kinase receptor gene. Upon ligand binding the FGFR2 receptors dimerise, and this is followed by activation of the intracellular tyrosine kinase domains. This initiates a cascade of signals that influence cell division and differentiation. FGFR2 mutations have been found in the Apert, Crouzon and Pfeiffer craniosynostosis syndromes. Most mutations are gain of function mutations, inducing ligand-independent receptor activation or altered ligand binding. With the exception of Apert syndrome, there is no clear genotype-phenotype correlation. Many different mutations have been found in Pfeiffer and Crouzon syndrome, but all of the mutations occur in the same extracellular region of the receptor. Identical mutations have been found in Pfeiffer and Crouzon syndrome. So within one family, both Crouzon and Pfeiffer syndrome may occur. Mutations in other FGFR-genes have also been found in craniosynostosis syndromes. Craniosynostosis caused by genetic factors includes a heterogeneous group of over 100 syndromes, most with autosomal domit inheritance. Mutations in five genes (FGFR1-, -2, -3, TWIST, and MSX2) causing craniosynostosis as the main clinical feature were described. In most of these conditions, there are also limb malformations. We report a two-generation kindred segregating microcornea, optic nerve alterations and cataract since childhood, craniosynostosis, and distal limb alterations, with a great clinical intrafamilial variability. The ophthalmological problems here described seem to be unique to this genealogy while similar feet alterations were apparently only described in two other affected siblings with acro-cranial-facial dysostosis syndrome (ADS). However, ADS has an autosomal recessive inheritance instead of the domit pattern of the present genealogy. The candidate exons of the five genes previously mentioned were tested through sequencing analysis presenting normal results in all cases. Therefore, clinical and laboratory analyses in our patients suggest that their phenotype represents a new syndrome very likely caused by mutation in a gene different from those studied. Craniosynostosis is a congenital developmental disorder involving premature fusion of cranial sutures, which results in an abnormal shape of the skull. Significant progress in understanding the molecular basis of this phenotype has been made for a small number of syndromic craniosynostosis forms. Nevertheless, in the majority of the approximately 100 craniosynostosis syndromes and in non-syndromic craniosynostosis the underlying gene defects and pathomechanisms are unknown. Here we report on a male infant presenting at birth with brachycephaly, proptosis, midfacial hypoplasia, and low set ears. Three dimensional cranial computer tomography showed fusion of the lambdoid sutures and distal part of the sagittal suture with a gaping anterior fontanelle. Mutations in the genes for FGFR2 and FGFR3 were excluded. Standard chromosome analysis revealed a de novo balanced translocation t(9;11)(q33;p15). The breakpoint on chromosome 11p15 disrupts the SOX6 gene, known to be involved in skeletal growth and differentiation processes. SOX6 mutation screening of another 104 craniosynostosis patients revealed one missense mutation leading to the exchange of a highly conserved amino acid (p.D68N) in a single patient and his reportedly healthy mother. The breakpoint on chromosome 9 is located in a region without any known or predicted genes but, interestingly, disrupts patches of evolutionarily highly conserved non-genic sequences and may thus led to dysregulation of flanking genes on chromosome 9 or 11 involved in skull vault development. The present case is one of the very rare reports of an apparently balanced translocation in a patient with syndromic craniosynostosis, and reveals novel candidate genes for craniosynostoses and cranial suture formation. We studied the transcriptional regulation of NELL-1, a craniosynostosis-related gene. We identitifed three OSE2 elements in the NELL-1 promoter that are directly bound and transactivated by Runx2. Forced expression of Runx2 induces NELL-1 expression in rat calvarial cells. INTRODUCTION: We previously reported the upregulation of NELL-1 in human craniosynostosis and the overexpression of Nell-1 in transgenic animals that induced premature suture closure associated with increased osteoblast differentiation. To study the transcriptional regulation of NELL-1, we analyzed the 5' flanking region of the human NELL-1 gene. We identified three osteoblast specific binding elements 2 (OSE2) sites (A, B, and C) within 2.2 kb upstream of the transcription start site and further studied the functionality of these sites. MATERIALS AND METHODS: An area of 2.2 kb and a truncated 325 bp, which lacked the three OSE sites, were cloned into a luciferase reporter gene, and co-transfected with Runx2 expression plasmid. The three OSE2 sites were individually mutated and co-transfected with Runx2 expression plasmid into Saos2 cells. Gel shifts and supershifts with Runx2 antibodies were used to determine specific binding to OSE2 sites. CHIP assays were used to study in vivo binding of Runx2 to the Nell-1 promoter. Runx2 expression plasmid was transfected into wildtype and Runx2(-/-) calvarial cells. Nell-1, osteocalcin, and Runx2 expression levels were measured using RT-PCR. RESULTS: Addition of Runx2 dose-dependently increased the luciferase activity in the human NELL-1 promoter-luciferase p2213. The p325 truncated NELL-1 construct showed significantly lower basal level of activity. Nuclear extract from Saos2 cells formed complexes with site A, B, and C probes and were supershifted with Runx2 antibody. Mutation of sites A, B, and C significantly decreased basal promoter activity. Furthermore, mutation of sites B and C had a blunted response to Runx2, whereas mutation of site A had a lesser effect. Runx2 bound to NELL-1 promoter in vivo. Transfection of Runx2 in rat osteoblasts upregulated Nell-1 and Ocn expression, and in Runx2 null calvarial cells, both Nell-1 and Ocn expression were rescued. CONCLUSIONS: Runx2 directly binds to the OSE2 elements and transactivates the human NELL-1 promoter. These results suggest that Nell-1 is likely a downstream target of Runx2. These findings may also extend our understanding of the molecular mechanisms governing the pathogenesis of craniosynostosis. Craniosynostosis is a common birth defect ( approximately 1/3,000 births) resulting from chromosome imbalances, gene mutations or unknown causes. We report a 6-month-old female with multiple sutural synostosis and prenatal onset growth deficiency, developmental delay, facial dysmorphism, congenital heart defect, and inguinal hernia. An integrated approach of standard cytogenetics, mBAND, locus-specific FISH, and 75 kb resolution array-CGH disclosed a complex chromosome 5 rearrangement, resulting in 3 paracentric inversions, 2 between-arm insertions, and partial duplication of 5q35. An extra copy of the MSX2 gene, which maps within the duplicated segment and is mutated in Boston-type craniosynostosis, was confirmed by molecular cytogenetic studies. Our study confirms that early fusion of cranial sutures commonly observed in the dup(5q) syndrome is caused by triplication of the MSX2 gene and strongly supports the crucial role of this gene in the development of craniofacial structures. We report on a 6-month-old boy with craniosynostosis, pseudohypoparathyroidism type 1a (PHP1A), and a GNAS gene mutation. He had synostoses of the coronal, frontal, and sagittal sutures, brachyturricephaly, and hydrocephaly. He also had congenital hypothyroidism, round face, full cheeks, shortness of limbs, mild developmental delay, and muscular hypotonia. Because of progressive hydrocephaly, the synostosis was corrected surgically but circulatory decompensation led to disseminated intravascular coagulation and cerebral infarctions. Our patient died 8 days later. Postmortem molecular studies of GNAS, the gene for guanine nucleotide-binding protein, alpha-stimulating activity polypeptide (gene for PHP1A), identified a de novo heterozygous 3 bp in frame deletion predicting a deletion of the asparagine residue at position 377 (deltaN377). This is the second report of this mutation. Results of molecular studies of craniosynostosis genes (FGFR2, FGFR3) and of numerous genetic variants predisposing to bleeding disorders were normal. We question whether craniosynostosis and trauma-induced bleeding disorder may be manifestations of PHP1A, or if our patient had two or three different congenital disorders. OBJECTIVES: We describe the first cohort-based analysis of the impact of genetic disorders in craniosynostosis. We aimed to refine the understanding of prognoses and pathogenesis and to provide rational criteria for clinical genetic testing. METHODS: We undertook targeted molecular genetic and cytogenetic testing for 326 children who required surgery because of craniosynostosis, were born in 1993-2002, presented to a single craniofacial unit, and were monitored until the end of 2007. RESULTS: Eighty-four children (and 64 relatives) had pathologic genetic alterations (86% single-gene mutations and 14% chromosomal abnormalities). The FGFR3 P250R mutation was the single largest contributor (24%) to the genetic group. Genetic diagnoses accounted for 21% of all craniosynostosis cases and were associated with increased rates of many complications. Children with an initial clinical diagnosis of nonsyndromic craniosynostosis were more likely to have a causative mutation if the synostoses were unicoronal or bicoronal (10 of 48 cases) than if they were sagittal or metopic (0 of 55 cases; P = .0003). Repeat craniofacial surgery was required for 58% of children with single-gene mutations but only 17% of those with chromosomal abnormalities (P = .01). CONCLUSIONS: Clinical genetic assessment is critical for the treatment of children with craniosynostosis. Genetic testing of nonsyndromic cases (at least for FGFR3 P250R and FGFR2 exons IIIa/c) should be targeted to patients with coronal or multisuture synostoses. Single-gene disorders that disrupt physiologic signaling in the cranial sutures often require reoperation, whereas chromosomal abnormalities follow a more-indolent course, which suggests a different, secondary origin of the associated craniosynostosis.
Are transcribed ultraconserved regions involved in cancer?
Yes, it appears that there is widespread T-UCR (Transcribed - UltraConserved Region) involvement in diverse cellular processes that are deregulated in the process of tumourigenesis. Transcribed ultraconserved regions (T-UCRs) are a subset of 481 sequences longer than 200 bp, which are absolutely conserved between orthologous regions of human, rat and mouse genomes, and are actively transcribed. It has recently been proven in cancer systems that differentially expressed T-UCRs could alter the functional characteristics of malignant cells.
Different classes of non-coding RNAs, including microRNAs, have recently been implicated in the process of tumourigenesis. In this study, we examined the expression and putative functions of a novel class of non-coding RNAs known as transcribed ultraconserved regions (T-UCRs) in neuroblastoma. Genome-wide expression profiling revealed correlations between specific T-UCR expression levels and important clinicogenetic parameters such as MYCN amplification status. A functional genomics approach based on the integration of multi-level transcriptome data was adapted to gain insights into T-UCR functions. Assignments of T-UCRs to cellular processes such as TP53 response, differentiation and proliferation were verified using various cellular model systems. For the first time, our results define a T-UCR expression landscape in neuroblastoma and suggest widespread T-UCR involvement in diverse cellular processes that are deregulated in the process of tumourigenesis. During recent years, novel approaches and new technologies have revealed a startling level of complexity of higher eukaryotes' transcriptome. A large proportion of the transcriptional output is represented by protein noncoding RNAs (ncRNAs) that arise from the "dark matter" of the genome. Focus on such sequences has revealed numerous RNA subtypes with several functions in RNA processing and gene expression regulation, and deep sequencing studies imply that many remain to be discovered. This review gives a picture of the state of the art of a novel class of long ncRNA known as transcribed-ultraconserved regions (T-UCRs). Most recent studies show that they are significantly altered in adult chronic lymphocytic leukemias, carcinomas, and pediatric neuroblastomas, leading to the hypothesis that UCRs may play a role in tumorigenesis and promising innovative future T-UCR-based therapeutic approaches. OBJECTIVES: The development of colorectal cancer (CRC) is characterized by multiple genetic alterations. Transcribed ultraconserved regions (T-UCRs) are a subset of 481 sequences longer than 200 bp, which are absolutely conserved between orthologous regions of human, rat and mouse genomes, and are actively transcribed. It has recently been proven in cancer systems that differentially expressed T-UCRs could alter the functional characteristics of maligt cells. Genome-wide profiling revealed that T-UCRs have distinct signatures in human leukemia and carcinoma. METHODS: In our study, we examined the expression levels of uc.43, uc.73, uc.134, uc.230, uc.339, uc.388 and uc.399 in 54 samples of primary colorectal carcinomas and 15 samples of non-tumoral adjacent tissues by real-time PCR. T-UCR expression levels were also correlated with commonly used clinicopathological features of CRC. RESULTS: Expression levels of uc.73 (p = 0.0139) and uc.388 (p = 0.0325) were significantly decreased in CRC tissue, and uc.73 indicated a positive correlation with overall survival (p = 0.0315). The lower expression of uc.388 was associated with the distal location of CRC (p = 0.0183), but no correlation of any evaluated T-UCR with clinical stage, grade and tumor diameter was observed. CONCLUSION: Our preliminary results suggest that uc.73 and uc.388 could be potential diagnostic and prognostic biomarkers in CRC patients. Much effort in cancer research has focused on the tiny part of our genome that codes for mRNA. However, it has recently been recognized that microRNAs also contribute decisively to tumorigenesis. Studies have also shown that epigenetic silencing by CpG island hypermethylation of microRNAs with tumor suppressor activities is a common feature of human cancer. The importance of other classes of non-coding RNAs, such as long intergenic ncRNAs (lincRNAs) and transcribed ultraconserved regions (T-UCRs) as altered elements in neoplasia, is also gaining recognition. Thus, we wondered whether there were other ncRNAs undergoing CpG island hypermethylation-associated inactivation in cancer cells. We focused on the small nucleolar RNAs (snoRNAs), a subset of ncRNA with a wide variety of cellular functions, such as chemical modification of RNA, pre-RNA processing and control of alternative splicing. By data mining snoRNA databases and the scientific literature, we selected 49 snoRNAs that had a CpG island within ≤ 2 Kb or that were processed from a host gene with a 5'-CpG island. Bisulfite genomic sequencing of multiple clones in normal colon mucosa and the colorectal cancer cell line HCT-116 showed that 46 snoRNAs were equally methylated in the two samples: completely unmethylated (n = 26) or fully methylated (n = 20). Most interestingly, the host gene-associated 5'-CpG islands of the snoRNAs SNORD123, U70C and ACA59B were hypermethylated in the cancer cells but not in the corresponding normal tissue. CpG island hypermethylation was associated with the transcriptional silencing of the respective snoRNAs. Results of a DNA methylation microarray platform in a comprehensive collection of normal tissues, cancer cell lines and primary maligcies demonstrated that the observed hypermethylation of snoRNAs was a common feature of various tumor types, particularly in leukemias. Overall, our findings indicate the existence of a new subclass of ncRNAs, snoRNAs, that are targeted by epigenetic inactivation in human cancer. Recent data have linked hypoxia, a classic feature of the tumor microenvironment, to the function of specific microRNAs (miRNAs); however, whether hypoxia affects other types of noncoding transcripts is currently unknown. Starting from a genome-wide expression profiling, we demonstrate for the first time a functional link between oxygen deprivation and the modulation of long noncoding transcripts from ultraconserved regions, termed transcribed-ultraconserved regions (T-UCRs). Interestingly, several hypoxia-upregulated T-UCRs, henceforth named 'hypoxia-induced noncoding ultraconserved transcripts' (HINCUTs), are also overexpressed in clinical samples from colon cancer patients. We show that these T-UCRs are predomitly nuclear and that the hypoxia-inducible factor (HIF) is at least partly responsible for the induction of several members of this group. One specific HINCUT, uc.475 (or HINCUT-1) is part of a retained intron of the host protein-coding gene, O-linked N-acetylglucosamine transferase, which is overexpressed in epithelial cancer types. Consistent with the hypothesis that T-UCRs have important function in tumor formation, HINCUT-1 supports cell proliferation specifically under hypoxic conditions and may be critical for optimal O-GlcNAcylation of proteins when oxygen tension is limiting. Our data gives a first glimpse of a novel functional hypoxic network comprising protein-coding transcripts and noncoding RNAs (ncRNAs) from the T-UCRs category.
In which breast cancer patients can palbociclib be used?
Palbociclib is useful for women with hormone receptor-positive, human epidermal growth factor receptor 2-negative breast cancer.
Women with hormone receptor-positive, human epidermal growth factor receptor 2- negative breast cancer-the most common subtype-have new options as palbociclib and similar drugs debut. This article outlines the rationale and evidence for their use.
Do patients with Pendred syndrome present congenital deafness?
Congenital deafness is one of the characteristics of Pendred syndrome patients.
Although 5% of all cases of congenital deafness are caused by Pendred's syndrome, there are few reports in the literature. Seven patients with Pendred's syndrome in three families living in the same village were detected. For that reason, the syndrome is reviewed in light of the literature. The sex distribution of the patients with Pendred's syndrome and their families was recorded. We tested for thyroxine, triiodothyronine, thyroid-stimulating hormone, triiodothyronine resin uptake, and perchlorate, and performed caloric testing. In one patient, subtotal thyroidectomy was performed. In the histopathologic study, a thyroid nodule filled with colloid was found. Chromosome studies showed no anomalies in any patient. Five of the patients were deaf-mutes. We observed that the parents were cousins in all three families. These families also had healthy children, and the existence of the syndrome in both sexes points to an autosomal recessive trait. OBJECTIVE: Pendred's syndrome is an association between congenital neurosensory deafness and goitre with abnormal discharge of iodide following perchlorate challenge, indicating a defect of iodide organification. Although Pendred's syndrome may cause up to 7.5% of all cases of congenital deafness, the molecular basis of the association between the hearing loss and the thyroid organification defect remains unknown. We chose to investigate the role of the thyroid peroxidase (TPO) gene as the genetic defect in Pendred's syndrome. DESIGN: A highly informative variable number tandem repeat (VNTR), located 1.5 kb downstream of exon 10 of the TPO gene, was used to search for genetic linkage in multiple sibships affected by Pendred's syndrome. PATIENTS: Seven kindreds were recruited from the UK, each with at least two affected members. We have also examined a large inbred Israeli family with two affected offspring and five unaffected children. MEASUREMENTS: Individuals were assigned affected status based on the characteristic clinical features of Pendred's syndrome, namely the presence of congenital sensorineural hearing loss and the appearance in early life of a goitre. Additionally, at least one affected member from each sibship had a characteristic positive perchlorate discharge test (Morgans & Trotter, 1958). PCR amplification of genomic DNA at the TPO VNTR allowed assignment of genotypes to each individual and the calculation of a two-point LOD score. RESULTS: In six of the nine sibships analysed we found obligatory recombination between TPO and Pendred's syndrome. Non-complementation observed in affected parents with an affected offspring excluded TPO in an affected sibship with genotype sharing and supports a hypothesis of genetic homogeneity for Pendred's syndrome. In two sibships, mutation of the TPO gene as the cause of Pendred's syndrome could not be excluded. CONCLUSIONS: These data suggest that defects at the thyroid peroxidase locus on chromosome 2 are not the major cause of Pendred's syndrome. Pendred's syndrome is manifested by congenital sensorineural deafness in association with familial goiter due to defective organic binding of iodine in the thyroid gland. The majority of patients with Pendred's syndrome are euthyroid. We report on an unusual case of a patient with Pendred's syndrome presenting with amenorrhea and late-onset hypothyroidism. Pendred syndrome is an autosomal recessive disorder characterized by goiter and congenital deafness. The primary defect is not yet known, although the gene causing Pendred syndrome has been localized very recently on chromosome 7q, a region that also contains a gene responsible for nonsyndromal hearing loss (DFNB4). We confirmed linkage to this chromosome 7 region in five Pendred families originating from different ethnic groups, with a highest cumulative lod score of 8.26 for marker D7S501. In combination with previous reports, our results define a candidate region for the Pendred gene of 1.7 cM flanked by markers D7S501 and D7S692. Pendred syndrome comprises the association of severe congenital sensorineural deafness with thyroid pathology. Although it is the commonest form of syndromic hearing loss, the primary genetic defect remains unknown. The variable clinical presentation allied to the difficulty in securing the diagnosis have resulted in relatively poor documentation of the radiological features of this syndrome. We now present data on 40 patients, all complying with strict diagnostic criteria for the disorder, and describe our experience of the prevalence of specific malformations of the inner ear as well as comparing the relative merits of computed tomography (CT) and magnetic resoce imaging (MRI) in the investigation of this inherited condition. Deficiency of the interscalar septum in the distal coils of the cochlea (Mondini deformity) was found to be a common but probably not a constant feature of Pendred syndrome. However, enlargement of the endolymphatic sac and duct in association with a large vestibular aqueduct was present in all 20 patients examined by MRI. We conclude that thin section high resolution MRI on a T2 protocol in the axial and sagittal planes is the imaging investigation of choice. Pendred's syndrome is an autosomal recessive disease characterized by goiter, impaired iodide organification, and congenital sensorineural deafness. The gene mutated in Pendred's syndrome, PDS (Pendred's syndrome gene), was cloned very recently and encodes the putative sulfate transporter pendrin. Pendred's syndrome may account for up to 10% of the cases with hereditary hearing loss, and pendrin mutations have also been found in a kindred with non-syndromic deafness. In this study, 41 individuals from a large, highly inbred pedigree from Northeastern Brazil were examined for features of Pendred's syndrome. Linkage studies and sequence analysis of the coding region of the PDS gene were performed with DNA from 36 individuals. The index patient, with the classical triad of deafness, positive perchlorate test, and goiter, was found to be homozygous for a deletion of thymidine 279 in exon 3, resulting in a frameshift and a premature stop codon at amino acid 96. This alteration resulted in truncation of the protein in the first transmembrane domain. Two other patients with deafness were found to be homozygous for this mutation; 19 were heterozygous and 14 were homozygous for the wild type allele. Surprisingly, 6 deaf individuals in this kindred were not homozygous for the PDS gene mutation; 3 were heterozygous and 3 were homozygous for the wild type allele, suggesting a probable distinct genetic cause for their deafness. All 3 homozygous individuals for the PDS mutation had goiters. However, goiters were also found in 10 heterozygous individuals and in 6 individuals without the PDS mutation and are most likely caused by iodine deficiency. In conclusion, we identified a novel mutation in the PDS gene causing Pendred's syndrome. The comparison of phenotype and genotype reveals, however, that phenocopies generated by distinct environmental and/or genetic causes are present in this kindred and that the diagnosis of Pendred's syndrome may be difficult without molecular analysis. Pendred's syndrome is an autosomal recessive disease characterized by goiter and congenital sensorineural deafness. Most patients with Pendred's syndrome are euthyroid, but the perchlorate test is positive indicating an impaired iodide organification. The sensorineural deafness is typically associated with a malformation of the inner ear, referred to as Mondini cochlea. The incidence of Pendred's syndrome is thought to be as high as 7.5 to 10 in 100,000 individuals, and it has been estimated to account for about 10% of the cases with hereditary deafness. Linkage of Pendred's syndrome to chromosome 7q22-31.1 was first established in 1996, and the Pendred's syndrome gene (PDS gene) was cloned in 1997. The PDS gene encodes pendrin, a highly hydrophobic 780 aminoacid protein with 11 transmembrane domains. Its function is unknown. Sequence comparison reveals a very high homology to several sulfate transporters suggesting that it could be a sulfate or anion transporter. A wide spectrum of mutations in the PDS gene has now been associated with Pendred's syndrome. Molecular analysis of the PDS gene is useful to make a definite diagnosis in familial and sporadic cases with Pendred's syndrome, and will be helpful for determining the true prevalence of this disorder. Pendred syndrome is the autosomal recessively transmitted association of familial goiter and congenital deafness. There is no specific biochemical marker of this disease, and the diagnosis depends upon the demonstration of the triad of congenital sensorineural hearing loss, goiter, and abnormal perchlorate discharge test. Pendred syndrome is caused by mutations within the putative ion transporter gene (PDS gene), located on chromosome 7q. A wide variation in the clinical presentation of this condition, and its well documented phenotypic overlap with other thyroid disorders (such as Hashimoto's thyroiditis), can lead to diagnostic difficulties. The potential for misdiagnosis increases when these disorders occur coincidentally in the same family. We describe a kindred in which Pendred syndrome, autoimmune thyroiditis, and simple goiter coexisted, to highlight these diagnostic pitfalls and to illustrate the use of mutational analysis in resolving diagnostic confusion. Pendred syndrome is an autosomal recessive disorder characterized by congenital deafness and goiter. The gene responsible for this syndrome is located on chromosome 7q31. The disorder is related to a defect in iodine organification, but the molecular basis of the defect remains unknown. We report two cases of Pendred syndrome, a young woman and her brother. The patients presented deafness, goiter that appeared in the prepubertal years, and a positive perchloriate discharge test. The genetic factors, clinical features, and diagnosis are reviewed. Although the textbook view of Pendred syndrome is that of an autosomal recessive condition characterized by deafness and goitre, it is increasingly clear that not all such patients present this classical clinical picture. Malformations of the inner ear, specifically enlargement of the vestibular aqueduct, are common in Pendred syndrome and mutations in the PDS (Pendred Syndrome) gene have been recorded in patients presenting with deafness and vestibular aqueduct dilatation only, without other features of Pendred syndrome. Since this is the most common radiological malformation of the cochlea in deaf patients, we investigated what proportion of such cases were due to mutation of the PDS gene. We assessed 57 patients referred with radiological evidence of vestibular aqueduct enlargement, by history, clinical examination, perchlorate discharge test and molecular analysis of the PDS locus. Forty-one patients (72%) had unequivocal evidence of Pendred syndrome. The finding of a single heterozygous mutation at the PDS gene in a further eight was strongly suggestive of a critical role for pendrin, the protein product of the PDS gene, in the generation of enlarged vestibular aqueducts in at least 86% (49/57 cases) of patients with this radiological malformation. Securing the diagnosis of Pendred syndrome may be difficult, especially in the single case. Goitre is an inconstant finding, and the perchlorate discharge test, although helpful, is of diagnostic value only if abnormal. Enlargement of the vestibular aqueduct should be considered as the most likely presentation of Pendred syndrome and should prompt specific investigation of that diagnostic possibility. Pendred syndrome might henceforth be recharacterized as deafness with enlargement of the vestibular aqueduct, which is sometimes associated with goitre. In this article we describe detailed pathological and molecular genetics studies in a consanguineous kindred with Pendred's syndrome. The index patient was a 53-year-old female patient with congenital deafness and goiter. Her parents were first-degree cousins. She had a large goiter (150 g) that had been present since childhood. One of her sisters and a niece are also deaf and have goiter as well. The presence of Pendred's syndrome was confirmed by a positive perchlorate test and the demonstration of a Mondini malformation. Thyroid function tests (under levothyroxine [LT4] therapy) were in the euthyroid range with a thyrotropin [TSH] level of 2.8 microU/mL (0.2-3.2), a serum total thyroxine (T4) of 90 nmol/L (54-142), and a serum total triiodothyronine (T3) of 2.7 nmol/L (0.8-2.4). Total thyroidectomy was performed, and the mass in the right lobe was found to have invaded adjacent tissues. The histopathological findings were consistent with a follicular carcinoma with areas of anaplastic transformation and lung metastasis. The patient was treated twice with 100 mCi 131iodine (3,700 MBq) and received suppressive doses of LT4. Postoperatively, the serum thyroglobulin (Tg) levels remained markedly elevated (2,352 to 41,336 ng/mL). The patient died of a sudden severe episode of hemoptysis. Sequence analysis of the PDS gene performed with DNA from the two relatives with Pendred's syndrome revealed the presence of a deletion of thymidine 279 in exon 3, a point mutation that results in a frameshift and a premature stop codon at codon 96 in the pendrin molecule. We concluded that prolonged TSH stimulation because of iodine deficiency or dyshormonogenesis in combination with mutations of oncogenes and/or tumor suppressor genes, may result in the development of follicular thyroid carcinomas that undergo transformation into anaplastic cancers. It is likely that these pathogenetic mechanisms have been involved in the development of aggressive metastatic thyroid cancer in this unusual patient with Pendred's syndrome. Deafness means partial or complete hearing impairment and is one of the most prevalent sensory defects in humans. It can be due to genetic or environmental causes or a combination of both and may be Syndromic (associated with additional clinical features) or nonsyndromic (no other recognizable abnormal associated phenotype). The overall impact of hearing impairment is greatly influenced by the severity of hearing defect and by the age of onset. If defect is severe and presents in early childhood, it has dramatic effect on speech acquisition and thereby cognitive and psychosocial development. The mutations shown in the paper results in the conformational changes of protein and influence the phenotype of the affected individuals. For recessive cases of deafness it is possible to reduce the incidence of deafness by carrier screening in the families with multiple affected individuals and genetic counselling. Pendred Syndrome can be characterized by the triad composed of familial goitre, abnormal perchlorate discharge and congenital deafness. Pendred syndrome and non-syndromic recessive deafness associated with enlarged vestibular aqueduct (NSRD with EVA) are caused by mutations in the SLC26A4 (PDS) gene. Unlike NSRD with EVA, Pendred syndrome is characterized by goiter, which may be present after early adulthood. However, the clinical diagnosis of these two disorders is difficult in deaf children. Expression of the SLC26A4 gene may be responsible for iodide transport in the thyroid as well as for formation and function of the inner ear. Here, we analyzed the SLC26A4 gene and performed thyroid function tests (FT3, FT4, TSH, and Thyroglobulin) on six congenitally deaf infants (mean age 2.7 years) with EVA. Mutation of the SLC26A4 gene was identified in five patients: four were compound heterozygous (H723R/919-2A>G, H723R/IVS15+5G>A, H723R/R581S, IVS7-2A>G/IVS8+1G>A), the fifth had a frameshift mutation (322delC). All the patients demonstrated an elevation of serum thyroglobulin level. FT3 level was elevated in four of the five patients. The patient who did not have a detectable gene mutation showed normal thyroid function. We conclude that the mutations in the SLC26A4 gene identified here are highly associated with high serum thyroglobulin levels in congenital and deafness infants. These mutations may be of value for the diagnosis of Pendred syndrome and NSRD with EVA. Pendred syndrome is an autosomal recessive disorder characterized by congenital sensorineural deafness, goiter, and impaired iodide organification. It is caused by mutations in the PDS gene. Most published mutation studies of Pendred syndrome have dealt with Western populations. In this study, we examined clinical and molecular characteristics of 16 affected individuals in 6 unrelated Thai families. Of all the affected, 100% (16/16) had bilateral deafness, 68.8% (11/16) goiters, and 25% (4/16) hypothyroidism. Follicular thyroid carcinoma and Hürthle cell adenoma were found in affected members of a family, raising the possibility of an increased risk of thyroid carcinoma in Pendred syndrome patients. Sequence analysis of the entire coding region of the PDS gene successfully identified all 12 mutant alleles in these 6 families. The 12 identified mutant alleles constituted 6 distinct mutations including 3 splice site mutations (IVS4-1G>A, IVS7-2A>G, IVS9- 1G>A), one frame shift mutation (1548insC) and 2 missense mutations (T67S, H723R). Eight mutations out of 12 were constituted by IVS7- 2A>G and 1548insC, each one being present in 4 distinct alleles in our studied group. The identification of these two frequent PDS mutations will facilitate the molecular diagnosis of Pendred syndrome in Thai populations. In addition, three newly identified mutations, T67S, IVS4-1G>A, and IVS9-1G>A, were not observed in 50 unrelated healthy Thai controls. CONTEXT: Goiter and deafness can be associated in some genetic syndromes, e.g. Pendred syndrome (PS) and resistance to thyroid hormone (RTH). PS is an autosomal recessive disorder characterized by goiter and sensorineural hearing impairment with an enlarged vestibular aqueduct bilaterally. RTH is an autosomal domit condition of reduced tissue sensitivity to thyroid hormone in which goiter is very frequent and hearing loss occurs in about 20% of patients. OBJECTIVE, PATIENTS, AND DESIGN: The objective of this study was to identify the cause of goiter and deafness in two sisters born to healthy unrelated parents. We present their history, clinical presentation, and follow-up and report the results of molecular genetic investigations. RESULTS: The elder sister had an elevated TSH level at newborn screening followed by subclinical hypothyroidism, childhood-onset goiter, and bilateral progressive sensorineural hearing impairment with enlarged vestibular aqueducts, consistent with a diagnosis of PS. Her younger sister had congenital goiter, elevated free T3 and free T4 concentrations with unsuppressed TSH, sinus tachycardia, and bilateral progressive sensorineural hearing impairment with enlarged vestibular aqueducts. This clinical presentation was consistent with a diagnosis of RTH, in which, however, inner ear malformations are uncommon. Interestingly, molecular genetic testing showed that, whereas the elder sister is affected by PS, the younger sister has both PS (due to compound heterozygous SLC26A4 mutations) and RTH (due to a novel de novo heterozygous THRB mutation). CONCLUSIONS: This is the first report of the cooccurrence, in the same individual, of PS and RTH, two genetic syndromes both associated with goiter and hearing impairment. Pendred syndrome (PDS) is an autosomal recessive disorder characterized by congenital deafness, goiter and iodide organification defect. Presence of inner ear malformations is essential for the clinical diagnosis. Most individuals with PDS are clinically and biochemically euthyroid. Mutations in the PDS gene encoding pendrin protein have been shown to be associated with PDS. It has been recently demonstrated that some families with features of PDS do not have the inner ear malformations and mutations in the PDS gene. This condition has been named as "pseudo-Pendred syndrome" (pseudo-PDS), and has been hypothesized to be of autoimmune origin. Here we report four siblings who have goiter, severe hypothyroidism, a positive perchlorate discharge test and sensorineural deafness, but not the inner ear abnormality which is diagnostic for PDS. We suggest that thyroid peroxidase (TPO) gene should be analyzed in pseudo-PDS patients with congenital goitrous hypothyroidism and deafness. INTRODUCTION: Pendred syndrome, a combination of sensorineural deafness, impaired organification of iodide in the thyroid and goitre, results from biallelic defects in pendrin (encoded by SLC26A4), which transports chloride and iodide in the inner ear and thyroid respectively. Recently, pendrin has also been identified in the kidneys, where it is found in the apical plasma membrane of non-α-type intercalated cells of the cortical collecting duct. Here, it functions as a chloride-bicarbonate exchanger, capable of secreting bicarbonate into the urine. Despite this function, patients with Pendred syndrome have not been reported to develop any significant acid-base disturbances, except a single previous reported case of metabolic alkalosis in the context of Pendred syndrome in a child started on a diuretic. CASE REPORT: We describe a 46-year-old female with sensorineural deafness and hypothyroidism, who presented with severe hypokalaemic metabolic alkalosis during inter-current illnesses on two occasions, and who was found to be homozygous for a loss-of-function mutation (V138F) in SLC26A4. Her acid-base status and electrolytes were unremarkable when she was well. CONCLUSION: This case illustrates that, although pendrin is not usually required to maintain acid-base homeostasis under ambient condition, loss of renal bicarbonate excretion by pendrin during a metabolic alkalotic challenge may contribute to life-threatening acid-base disturbances in patients with Pendred syndrome. Pendred syndrome and DFNB4 (autosomal recessive nonsyndromic congenital deafness, locus 4) are associated with autosomal recessive congenital sensorineural hearing loss and mutations in the SLC26A4 gene. Extensive allelic heterogeneity, however, necessitates analysis of all exons and splice sites to identify mutations for individual patients. Although Sanger sequencing is the gold standard for mutation detection, screening methods supplemented with targeted sequencing can provide a cost-effective alternative. One such method, denaturing high-performance liquid chromatography, was developed for clinical mutation detection in SLC26A4. However, this method inherently cannot distinguish homozygous changes from wild-type sequences. High-resolution melting (HRM), on the other hand, can detect heterozygous and homozygous changes cost-effectively, without any post-PCR modifications. We developed a closed-tube HRM mutation detection method specific for SLC26A4 that can be used in the clinical diagnostic setting. Twenty-eight primer pairs were designed to cover all 21 SLC26A4 exons and splice junction sequences. Using the resulting amplicons, initial HRM analysis detected all 45 variants previously identified by sequencing. Subsequently, a 384-well plate format was designed for up to three patient samples per run. Blinded HRM testing on these plates of patient samples collected over 1 year in a clinical diagnostic laboratory accurately detected all variants identified by sequencing. In conclusion, HRM with targeted sequencing is a reliable, simple, and cost-effective method for SLC26A4 mutation screening and detection. Thyroid hormones are essential for normal development and metabolism. Their synthesis requires transport of iodide into thyroid follicles. The mechanisms involving the apical efflux of iodide into the follicular lumen are poorly elucidated. The discovery of mutations in the SLC26A4 gene in patients with Pendred syndrome (congenital deafness, goiter, and defective iodide organification) suggested a possible role for the encoded protein, pendrin, as an apical iodide transporter. We determined whether TSH regulates pendrin abundance at the plasma membrane and whether this influences iodide efflux. Results of immunoblot and immunofluorescence experiments reveal that TSH and forskolin rapidly increase pendrin abundance at the plasma membrane through the protein kinase A pathway in PCCL-3 rat thyroid cells. The increase in pendrin membrane abundance correlates with a decrease in intracellular iodide as determined by measuring intracellular (125)iodide and can be inhibited by specific blocking of pendrin. Elimination of the putative protein kinase A phosphorylation site T717A results in a diminished translocation to the membrane in response to forskolin. These results demonstrate that pendrin translocates to the membrane in response to TSH and suggest that it may have a physiological role in apical iodide transport and thyroid hormone synthesis. OBJECTIVES: Mutations in the SLC26A4 gene (7q22.3-7q31.1) are considered one of the most common causes of genetic hearing loss. There are two clinical forms related to these mutations: syndromic and non-syndromic deafness. The first one is named Pendred Syndrome (PS) when deafness is associated with thyroid goiter; the second is called DFNB4, when no other symptoms are present. Both are transmitted as an autosomal recessive trait, but simple heterozygotes can develop both forms of deafness. Actually it is thought that Pendred Syndrome occurs when both alleles of SLC26A4 gene are mutated; DFNB4 seems due to monoallelic mutations. PS and DFNB4 can be associated with inner ear malformations. In most of the cases (around 80%), these consist in Enlarged Vestibular Aqueduct (EVA). EVA can also be present without SLC26A4 mutations. Understanding the role of new SLC26A4 variants should facilitate clinical assessment, as well as diagnostic and therapeutic approaches. This investigation aims to detect and report genetic causes of two unrelated Italian boys with hearing loss. METHODS: Patients and family members underwent clinical, audiological and genetic evaluations. To identify genetic mutations, DNA sequencing of SLC26A4 gene (including all 21 exons, exon-intron boundaries and promoter region) was carried out. RESULTS: Both probands were affected by congenital, progressive and fluctuating mixed hearing loss. Temporal bone imaging revealed a bilateral EVA with no other abnormalities in both cases. Probands were heterozygotes for previously undescribed mutations in the SLC26A4 gene: R409H/IVS2+1delG (proband 1) and L236P/K590X (proband 2). No other mutations were detected in GJB2, GJB6 genes or mitochondrial DNA (mit-DNA). CONCLUSIONS: The IVS2+1delG and K590X mutations have not yet been described in literature but there is some evidence to suggest that they have a pathological role. The results underlined the importance of considering the complete DNA sequencing of the SLC26A4 gene for differential molecular diagnosis of deafness, especially in those patients affected by congenital, progressive and fluctuating mixed hearing loss with bilateral EVA.
List side effects of SGLT2 inhibitors?
SGLT2 inhibitors can be associated with urogenital infections related to the enhanced glycosuria, and low blood pressure.
BACKGROUND: The kidney plays an important role in glucose metabolism, and has been considered a target for therapeutic intervention. The sodium-glucose cotransporter type 2 (SGLT2) mediates most of the glucose reabsorption from the proximal renal tubule. Inhibition of SGLT2 leads to glucosuria and provides a unique mechanism to lower elevated blood glucose levels in diabetes. The purpose of this review is to explore the physiology of SGLT2 and discuss several SGLT2 inhibitors which have clinical data in patients with type 2 diabetes. METHODS: We performed a PubMed search using the terms "SGLT2" and "SGLT2 inhibitor" through April 10, 2012. Published articles, press releases, and abstracts presented at national and international meetings were considered. RESULTS: SGLT2 inhibitors correct a novel pathophysiological defect, have an insulin-independent action, are efficacious with glycosylated hemoglobin reduction ranging from 0.5% to 1.5%, promote weight loss, have a low incidence of hypoglycemia, complement the action of other antidiabetic agents, and can be used at any stage of diabetes. They are generally well tolerated. However, due to side effects, such as repeated urinary tract and genital infections, increased hematocrit, and decreased blood pressure, appropriate patient selection for drug initiation and close monitoring after initiation will be important. Results of ongoing clinical studies of the effect of SGLT2 inhibitors on diabetic complications and cardiovascular safety are crucial to determine the risk-benefit ratio. A recent decision by the Committee for Medicinal Products for Human Use of the European Medicines Agency has recommended approval of dapagliflozin for the treatment of type 2 diabetes as an adjunct to diet and exercise, in combination with other glucose-lowering medicinal products, including insulin, and as a monotherapy for metformin-intolerant patients. Clinical research also remains to be carried out on the long-term effects of glucosuria and other potential effects of SGLT2 inhibitors, especially in view of the observed increase in the incidence of bladder and breast cancer. SGLT2 inhibitors represent a promising approach for the treatment of diabetes, and could potentially be an addition to existing therapies. Canagliflozin, an oral inhibitor of sodium/glucose cotransporter 2 (SGLT2) in the kidneys, leads to glucosuria and provides a unique mechanism to lower blood glucose levels in diabetes. It corrects a novel pathophysiological defect, has an insulin-independent action, reduces HbA1c by 0.5 to 1.1%, promotes weight loss, has a low incidence of hypoglycemia, complements the action of other antidiabetic agents, can be used at any stage of diabetes and appears to be safe in patients with compromised renal function. Due to side effects such as urinary tract and genital infections and decrease in blood pressure, proper patient selection for drug initiation and close monitoring will be important. Results of ongoing cardiovascular safety trials are important to determine the risk-benefit ratio. Canagliflozin is the first oral SGLT2 inhibitor approved in the U.S. market and it represents a promising approach for the treatment of diabetes in this era of increasing obesity. AIMS: Urinary tract infection (UTI) is a common clinical problem in diabetic patients; however, the relationship between UTI and glucosuria remains uncertain. To investigate the relationship, we examined the effect of glucosuria induced by sodium glucose cotransporter 2 (SGLT2) inhibitors on the progression of UTI in mice. METHODS: From 1 day before transurethral inoculation with Candida albicans, female mice were treated orally once a day with an SGLT2 inhibitor in different treatment regimens: (i) dapagliflozin at 10 mg/kg for 2, 3 or 7 days, (ii) dapagliflozin at 0.1, 1 or 10 mg/kg for 3 days and (iii) dapagliflozin, canagliflozin or tofogliflozin at 10 mg/kg for 3 days. To evaluate the ascending UTI, the kidneys were removed 6 days after the inoculation, and the number of viable C. albicans cells in kidney was measured as colony-forming units (CFU). RESULTS: In mice treated with dapagliflozin, the number of C. albicans CFU in kidney increased in accordance with both treatment duration and dose. The number of CFU significantly increased when mice were treated with 10 mg/kg dapagliflozin or canagliflozin but not tofogliflozin. With dapagliflozin and canagliflozin, urine glucose concentration (UGC) significantly increased up to 24 h after drug administration; with tofogliflozin, UGC significantly increased only up to 12 h after drug administration. CONCLUSIONS: Our data indicate that increased susceptibility to UTI is associated with a persistent increase in UGC. Treatment of type 2 diabetes (T2DM) continues to present challenges, with significant proportion of patients failing to achieve and maintain glycemic targets. Despite the availability of many oral antidiabetic agents, therapeutic efficacy is offset by side effects such as weight gain and hypoglycemia. Therefore, the search for novel therapeutic agents with an improved benefit-risk profile continues. Recent research has focused on the kidney as a potential therapeutic target, especially because maximal renal glucose reabsorption is increased in T2DM. Under normal physiological conditions, nearly all filtered glucose is reabsorbed in the proximal tubule of the nephron, principally via the sodium-glucose cotransporter 2 (SGLT2). SGLT2-inhibitors are a new class of oral antidiabetics, which reduce hyperglycemia by increasing urinary glucose excretion independently of insulin secretion or action. Clinical results are promising with significant lowering of HbA1c without increased risk of hypoglycemia, reduction of body weight and reduction of systolic blood pressure. Dapagliflozin is the first highly selective SGLT2-inhibitor approved by the European Medecine Agency. Canagliflozin and empagliflozin are undergoing phase III trials. Actual safety issues are an increased risk for genital- and urinary tract infections and a possible increased risk for bladder and breast cancer. This led to refusal of dapagliflozin by the Food and Drug Administration (FDA). A large randomized control trial is therefore warranted by the FDA. This review provides an overview of the current evidence available so far on the therapeutic potential of the SGLT2-inhibitors for the treatment of T2DM. Type 2 diabetes is characterized by decreased insulin secretion and sensitivity. The available oral anti-diabetic drugs act on many different molecular sites. The most used of oral anti-diabetic agents is metformin that activates glucose transport vesicles to the cell surface. Others are: the sulphonylureas; agents acting on the incretin system; GLP-1 agonists; dipetidylpeptidase-4 inhibitors; meglinitide analogues; and the thiazolidinediones. Despite these many drugs acting by different mechanisms, glycaemic control often remains elusive. None of these drugs have a primary renal mechanism of action on the kidneys, where almost all glucose excreted is normally reabsorbed. That is where the inhibitors of glucose reuptake (sodium-glucose cotransporter 2, SGLT2) have a unique site of action. Promotion of urinary loss of glucose by SGLT2 inhibitors embodies a new principle of control in type 2 diabetes that has several advantages with some urogenital side-effects, both of which are evaluated in this review. Specific approvals include use as monotherapy, when diet and exercise alone do not provide adequate glycaemic control in patients for whom the use of metformin is considered inappropriate due to intolerance or contraindications, or as add-on therapy with other anti-hyperglycaemic medicinal products including insulin, when these together with diet and exercise, do not provide adequate glycemic control. The basic mechanisms are improved β-cell function and insulin sensitivity. When compared with sulphonylureas or other oral antidiabetic agents, SGLT2 inhibitors provide greater HbA1c reduction. Urogenital side-effects related to the enhanced glycosuria can be troublesome, yet seldom lead to discontinuation. On this background, studies are analysed that compare SGLT2 inhibitors with other oral antidiabetic agents. Their unique mode of action, unloading the excess glycaemic load, contrasts with other oral agents that all act to counter the effects of diabetic hyperglycaemia. Inhibitors of sodium-glucose co-transporter type 2 (SGLT2) are proposed as a novel approach for the management of type 2 diabetes mellitus (T2DM). Several compounds are already available in many countries (dapagliflozin, canagliflozin, empagliflozin and ipragliflozin) and some others are in a late phase of development. The available SGLT2 inhibitors share similar pharmacokinetic characteristics, with a rapid oral absorption, a long elimination half-life allowing once-daily administration, an extensive hepatic metabolism mainly via glucuronidation to inactive metabolites, the absence of clinically relevant drug-drug interactions and a low renal elimination as parent drug. SGLT2 co-transporters are responsible for reabsorption of most (90 %) of the glucose filtered by the kidneys. The pharmacological inhibition of SGLT2 co-transporters reduces hyperglycaemia by decreasing renal glucose threshold and thereby increasing urinary glucose excretion. The amount of glucose excreted in the urine depends on both the level of hyperglycaemia and the glomerular filtration rate. Results of numerous placebo-controlled randomised clinical trials of 12-104 weeks duration have shown significant reductions in glycated haemoglobin (HbA1c), resulting in a significant increase in the proportion of patients reaching HbA1c targets, and a significant lowering of fasting plasma glucose when SGLT2 inhibitors were administered as monotherapy or in addition to other glucose-lowering therapies including insulin in patients with T2DM. In head-to-head trials of up to 2 years, SGLT2 inhibitors exerted similar glucose-lowering activity to metformin, sulphonylureas or sitagliptin. The durability of the glucose-lowering effect of SGLT2 inhibitors appears to be better; however, this remains to be more extensively investigated. The risk of hypoglycaemia was much lower with SGLT2 inhibitors than with sulphonylureas and was similarly low as that reported with metformin, pioglitazone or sitagliptin. Increased renal glucose elimination also assists weight loss and could help to reduce blood pressure. Both effects were very consistent across the trials and they represent some advantages for SGLT2 inhibitors when compared with other oral glucose-lowering agents. The pharmacodynamic response to SGLT2 inhibitors declines with increasing severity of renal impairment, and prescribing information for each SGLT2 inhibitor should be consulted regarding dosage adjustments or restrictions in moderate to severe renal dysfunction. Caution is also recommended in the elderly population because of a higher risk of renal impairment, orthostatic hypotension and dehydration, even if the absence of hypoglycaemia represents an obvious advantage in this population. The overall effect of SGLT2 inhibitors on the risk of cardiovascular disease is unknown and will be evaluated in several ongoing prospective placebo-controlled trials with cardiovascular outcomes. The impact of SGLT2 inhibitors on renal function and their potential to influence the course of diabetic nephropathy also deserve more attention. SGLT2 inhibitors are generally well-tolerated. The most frequently reported adverse events are female genital mycotic infections, while urinary tract infections are less commonly observed and generally benign. In conclusion, with their unique mechanism of action that is independent of insulin secretion and action, SGLT2 inhibitors are a useful addition to the therapeutic options available for the management of T2DM at any stage in the natural history of the disease. Although SGLT2 inhibitors have already been extensively investigated, further studies should even better delineate the best place of these new glucose-lowering agents in the already rich armamentarium for the management of T2DM. SGLT2 (Sodium Glucose co-Transporter 2 Inhibitors) inhibitors are a new group of oral medications for the treatment of type 2 diabetes mellitus patients. These medications interfere with the process of glucose reabsorption in the proximal convoluted tubules in the kidneys, therefore increasing both glucose and water diuresis. SGLT2 inhibitors were found to be effective in lowering HbA1c levels in double-blinded studies, both as monotherapy and in combination with other oral hypoglycemic medications of various other mechanisms of action. SGLT2 Inhibitors are not a risk factor for hypoglycemia and are suitable for combination with insulin therapy. Their unique mode of action, relying on glomerular filtration, make these medication unsuitable for usage as treatment for type 2 diabetes patients who are also suffering from moderate to severe renal failure. Their main adverse effects are increased risk for urinary and genital tract infections. The following review describes the relevant pathophysiology addressed by these novel medications, evidence for efficacy and the safety profile of SGLT2 Inhibitors.
Is CD56 useful in Ewing sarcoma prognosis?
Excellent prognosis in a subset of patients with Ewing sarcoma identified at diagnosis by CD56 using flow cytometryIn patients with localized nonpelvic disease, those expressing low/negative CD56 had 100% PFS versus 40% in the high expressing group (P = 0.02)
A thorough literature search revealed no previous reports of this entity, and we are the first to describe a case of a high-grade sarcoma arising from a recurrent immature teratoma misdiagnosed as growing teratoma syndrome. The patient was a 23-yr-old female, diagnosed at the age of 20 with a Stage IIIB immature ovarian teratoma. After surgery and chemotherapy, the patient developed multiple liver and pelvic masses that were diagnosed as mature teratomas based on small samples obtained by computed tomography-guided core biopsy. Three years after diagnosis the patient presented with severe respiratory difficulty and following resection, the final pathology revealed multiple tumors with foci of high grade sarcoma compatible with primitive neuroectodermal tumor/extraskeletal Ewing sarcoma based on morphology and immunohistochemistry (CD99, CD56). However, on the basis of further immunostaining and fluorescent in situ hybridization studies negative for rearrangement of EWSR1, the final pathologic diagnosis was high-grade unspecified (undifferentiated) sarcoma. This case illustrates the pitfalls of biopsying 1 site in a patient with recurrence of a heterogeneous tumor such as immature ovarian teratoma, especially when rendering a benign diagnosis such as growing teratoma syndrome. It is of utmost importance to adequately sample large-volume recurrent teratomas, and we suggest biopsying several different sites, to increase the likelihood of detecting a maligt component.
What is the method FASP used for?
Filter Aided Sample Preparation (FASP), a type of proteomic reactor, in which samples dissolved in sodium dodecyl sulfate (SDS) are digested in an ultrafiltration unit.
Chlorobaculum (Cba.) tepidum is a green sulfur bacterium that oxidizes sulfide, elemental sulfur, and thiosulfate for photosynthetic growth. To gain insight into the sulfur metabolism, the proteome of Cba. tepidum cells sampled under different growth conditions has been quantified using a rapid gel-free, filter-aided sample preparation (FASP) protocol with an in-solution isotopic labeling strategy. Among the 2245 proteins predicted from the Cba. tepidum genome, approximately 970 proteins were detected in unlabeled samples, whereas approximately 630-640 proteins were detected in labeled samples comparing two different growth conditions. Wild-type cells growing on thiosulfate had an increased abundance of periplasmic cytochrome c-555 and proteins of the periplasmic thiosulfate-oxidizing SOX enzyme system when compared with cells growing on sulfide. A dsrM mutant of Cba. tepidum, which lacks the dissimilatory sulfite reductase DsrM protein and therefore is unable to oxidize sulfur globules to sulfite, was also investigated. When compared with wild type, the dsrM cells exhibited an increased abundance of DSR enzymes involved in the initial steps of sulfur globule oxidation (DsrABCL) and a decreased abundance of enzymes putatively involved in sulfite oxidation (Sat-AprAB-QmoABC). The results show that Cba. tepidum regulates the cellular levels of enzymes involved in sulfur metabolism and other electron-transferring processes in response to the availability of reduced sulfur compounds. Analytical advantages of using multiple enzymes for sample digestion (MED), primarily an increase of sequence coverage, have been reported in several studies. However, this approach is only rarely used, mainly because it requires additional sample and mass spectrometric measurement time. We have previously described Filter Aided Sample Preparation (FASP), a type of proteomic reactor, in which samples dissolved in sodium dodecyl sulfate (SDS) are digested in an ultrafiltration unit. In FASP, such as in any other preparation protocol, a portion of sample remains after digestion and peptide elution. Making use of this fact, we here develop a protocol enabling consecutive digestion of the sample with two or three enzymes. By use of the FASP method, peptides are liberated after each digestion step and remaining material is subsequently cleaved with the next proteinase. We observed excellent performance of the ultrafiltration devices in this mode, allowing efficient separation of orthogonal populations of peptides, resulting in an increase in the numbers of identified peptides and proteins. At the low microgram level, we found that the consecutive use of endoproteinases LysC and trypsin enabled identification of up to 40% more proteins and phosphorylation sites in comparison to the commonly used one-step tryptic digestion. MED-FASP offers efficient exploration of previously unused sample material, increasing depth of proteomic analyses and sequence coverage. Zymogen granule (ZG) constituents play important roles in pancreatic injury and disease. In previous studies, proteomic analyses with rat zymogen granules were separated by two-dimensional gel electrophoresis or one-dimensional SDS-PAGE, followed by in-gel tryptic digestion. In order to overcome the disadvantage of in-gel digestion and to carry out further in-depth proteomic analysis of the zymogen granules, in this study, by combining a filter-aided sample preparation method and fully automated 2D-LC-MS/MS technique, 800 ZG proteins were identified with at least two unique peptides for each protein, 75% of which have not been previously reported. The identified proteins revealed broad diversity in protein identity and function. This is the largest dataset of ZG proteome, and also the first dataset of the mouse ZG proteome, which may help elucidate on the molecular architecture of ZGs and their functions. The expanding use of surfactants for proteome sample preparations has prompted the need to systematically optimize the application and removal of these MS-deleterious agents prior to proteome measurements. Here we compare four detergent cleanup methods (trichloroacetic acid (TCA) precipitation, chloroform/methanol/water (CMW) extraction, a commercial detergent removal spin column method (DRS) and filter-aided sample preparation (FASP)) to provide efficiency benchmarks with respect to protein, peptide, and spectral identifications in each case. Our results show that for protein-limited samples, FASP outperforms the other three cleanup methods, while at high protein amounts, all the methods are comparable. This information was used to investigate and contrast molecular weight-based fractionated with unfractionated lysates from three increasingly complex samples ( Escherichia coli K-12, a five microbial isolate mixture, and a natural microbial community groundwater sample), all of which were prepared with an SDS-FASP approach. The additional fractionation step enhanced the number of protein identifications by 8% to 25% over the unfractionated approach across the three samples. The performance of two proteomic sample preparation methods, "pseudoshotgun" (PSG) and filter-aided sample preparation (FASP) were compared in terms of the number of identified proteins, representation of cellular component GO (gene ontology) categories in the obtained list of proteins, and the efficiency of both methods in the proteomic analysis of a very low number of cells. Both methods were combined to obtain a proteomic profile of a short-term culture (passage 3) of melanoma cells, established in our laboratory from a human metastatic melanoma lesion. The data revealed that with FASP, usually more proteins are identified than with PSG when analyzing a higher number of cells (≥ 5000/injection), whereas PSG is favorable when analyzing only a very small amount of cells (250-500/injection). PSG and FASP, however, are complementary techniques, as combining both methods further increases the number of identified proteins. Moreover, we show that it is feasible to identify a substantial number of proteins from only 250 cells/injection that is equivalent to 60 ng of protein. A novel form of ovomacroglobulin/ovostatin (OVOS2) predicted from EST data was previously identified in the chicken ovarian cancer model using a mass spectrometry-based shotgun label-free proteomics strategy. The quantitative label-free data from plasma showed a significant increase over time with the spontaneous onset and progression of ovarian cancer making it a potential protein biomarker for further study. Two other proteins of interest identified from this initial study included vitellogenin-1 (Vit-1), a lipid-transport protein tied to egg production, and transthyretin (TTR), a retinol binding transport protein currently used in the clinical management of ovarian cancer. A multiplexed protein cleavage isotope dilution mass spectrometry (PC-IDMS) assay was developed to quantify OVOS2, Vit-1, and TTR by selected reaction monitoring (SRM). A total of 6 stable isotope labeled (SIL) peptide standards were used in the assay with three tryptic peptides from OVOS2, one for Vit-1, and two for TTR. The assay was developed for use with un-depleted raw plasma combined with the filter assisted sample preparation (FASP) method and its use was also demonstrated for matched ovary tissue samples. The PC-IDMS data for the two TTR peptides did not correlate with each other with more than a 10-fold difference in concentration for all 5 time points measured. The PC-IDMS data from the longitudinal plasma samples correlated well for OVOS2 and Vit-1 whereas TTR was inconclusive. Interestingly, the absolute amount for one of the OVOS2 SIL peptides was 2-fold less compared with the other two SIL peptides. These data illustrate the successes and challenges of qualifying quantitative levels of proteins from an in-gel digestion sample preparation followed by LC-MS/MS (GeLC) label-free discovery-based approach to a targeted SRM-based quantitative assay in plasma and tissues. This work presents a comparative evaluation of several detergent-based sample preparation workflows for the MS-based analysis of bacterial proteomes, performed using the model organism Escherichia coli. Initially, RapiGest- and SDS-based buffers were compared for their protein extraction efficiency and quality of the MS data generated. As a result, SDS performed best in terms of total protein yields and overall number of MS identifications, mainly due to a higher efficiency in extracting high molecular weight (MW) and membrane proteins, while RapiGest led to an enrichment in periplasmic and fimbrial proteins. Then, SDS extracts underwent five different MS sample preparation workflows, including: detergent removal by spin columns followed by in-solution digestion (SC), protein precipitation followed by in-solution digestion in ammonium bicarbonate or urea buffer, filter-aided sample preparation (FASP), and 1DE separation followed by in-gel digestion. On the whole, about 1000 proteins were identified upon LC-MS/MS analysis of all preparations (>1100 with the SC workflow), with FASP producing more identified peptides and a higher mean sequence coverage. Each protocol exhibited specific behaviors in terms of MW, hydrophobicity, and subcellular localization distribution of the identified proteins; a comparative assessment of the different outputs is presented. Preserved clinical material is a unique source for proteomic investigation of human disorders. Here we describe an optimized protocol allowing large scale quantitative analysis of formalin fixed and paraffin embedded (FFPE) tissue. The procedure comprises four distinct steps. The first one is the preparation of sections from the FFPE material and microdissection of cells of interest. In the second step the isolated cells are lysed and processed using 'filter aided sample preparation' (FASP) technique. In this step, proteins are depleted from reagents used for the sample lysis and are digested in two-steps using endoproteinase LysC and trypsin. After each digestion, the peptides are collected in separate fractions and their content is determined using a highly sensitive fluorescence measurement. Finally, the peptides are fractionated on 'pipette-tip' microcolumns. The LysC-peptides are separated into 4 fractions whereas the tryptic peptides are separated into 2 fractions. In this way prepared samples allow analysis of proteomes from minute amounts of material to a depth of 10,000 proteins. Thus, the described workflow is a powerful technique for studying diseases in a system-wide-fashion as well as for identification of potential biomarkers and drug targets. Primary tissue samples are valuable resources for investigators interested in understanding disease. In order to maximize the information content that can be gained from these precious samples, proper storage, handling, and preparation are essential. Some tissue preservation techniques utilize the cryopreservation medium, optimal cutting temperature (OCT) compound. While this medium provides benefits for traditional molecular studies, certain components can interfere with mass spectrometric analyses. Mass spectrometry based proteomics is a growing field with many applications for disease research. Our goal is to determine a reliable method for separating the proteins from the contaminating species in OCT embedded samples, thus making these samples compatible with mass spectrometric analyses. The novel applications of ether-methanol precipitation, filter-aided sample preparation (FASP), and SDS-PAGE provide researchers with protocols for removing OCT contaminating species from valuable samples. The results presented in this study show that all three methods reproducibly remove OCT; however, precipitation and FASP outperform SDS-PAGE by common proteomic metrics. Discovery-based proteomic studies aim to answer important biological questions by identifying as many proteins as possible. In order to accomplish this lofty goal, an effort must be placed on determining an optimal workflow that maximizes protein identifications. In this study, we compare protein extraction, digestion and fractionation methods for bottom-up proteomics using a human colon cancer cell line as our model system. Four different buffers for protein extraction, two digestion approaches, as well as three sample fractionation methods were evaluated in order to determine an accessible workflow that gives maximal protein identifications. Samples comparing these workflows were analyzed via UPLC paired with tandem MS on a Q-Exactive mass spectrometer. Our goal is to determine an optimal workflow to enable users to maximize protein identifications. Our results show that an increased number of confident protein identifications are attained with a filter-aided digestion approach as compared to an in-solution digestion. Overall SDS-PAGE fractionation leads to higher numbers of identifications than SCX SpinTip and reverse phased cartridge platforms. The novel aspect of this work is the comparison of two readily available, offline platforms for fractionation in reference to a traditional technique, SDS-PAGE. Deamidation of asparagine and glutamine residues is a common post-translational modification. Researchers often rely on mass spectrometric based proteomic techniques for the identification of these post-translational sites. Mass spectral analysis of deamidated peptides is complicated and often misassigned due to overlapping (13)C peak of the amidated form with the deamidated monoisotopic peak; these two peaks are only separated by 19.34 mDa. For proper assignment, it is inherently important to use a mass spectrometer with high mass measurement accuracy and high resolving power. Herein, mouse brain tissue lysate was prepared using filter-aided sample preparation (FASP) method and Stage Tip fractionation followed by analysis on a oLC coupled with a quadrupole orbitrap (Q-Exactive) mass spectrometer to accurately identify more than 5400 proteins. Mass spectral data was processed using MASCOT and ProteoIQ for accurate identification of peptides and proteins. MASCOT search values for precursor and MS/MS mass tolerances were investigated, and it was determined that data searched with greater than 5 ppm precursor mass tolerance resulted in the misassignment of deamidated peptides. Peptides that were identified with a mass measurement accuracy of ±5 ppm were correctly assigned. In this work, for the first time, hydrazide functionalized PAMAM was designed and synthesized for efficient and selective enrichment of N-linked glycopeptides from complex biological samples using FASP (filter-aided sample preparation) mode.
What is the role of extracellular signal-related kinases 1 and 2 (ERK1/2) proteins in craniosynostosis?
Reduced dosage of ERF, which encodes an inhibitory ETS transcription factor directly bound by ERK1/2 causes complex craniosynostosis (premature fusion of the cranial sutures) in humans and mice. Features of this newly recognized clinical disorder include multiple-suture synostosis, craniofacial dysmorphism, Chiari malformation and language delay.
The extracellular signal-related kinases 1 and 2 (ERK1/2) are key proteins mediating mitogen-activated protein kinase signaling downstream of RAS: phosphorylation of ERK1/2 leads to nuclear uptake and modulation of multiple targets. Here, we show that reduced dosage of ERF, which encodes an inhibitory ETS transcription factor directly bound by ERK1/2 (refs. 2,3,4,5,6,7), causes complex craniosynostosis (premature fusion of the cranial sutures) in humans and mice. Features of this newly recognized clinical disorder include multiple-suture synostosis, craniofacial dysmorphism, Chiari malformation and language delay. Mice with functional Erf levels reduced to ∼30% of normal exhibit postnatal multiple-suture synostosis; by contrast, embryonic calvarial development appears mildly delayed. Using chromatin immunoprecipitation in mouse embryonic fibroblasts and high-throughput sequencing, we find that ERF binds preferentially to elements away from promoters that contain RUNX or AP-1 motifs. This work identifies ERF as a novel regulator of osteogenic stimulation by RAS-ERK signaling, potentially by competing with activating ETS factors in multifactor transcriptional complexes.
Are there any urine biomarkers for chronic kidney disease?
Chronic kidney disease (CKD), is a progressive loss in renal function over a period of months or years. The symptoms of worsening kidney function are non-specific, and might include feeling generally unwell and experiencing a reduced appetite. Often, chronic kidney disease is diagnosed as a result of screening of people known to be at risk of kidney problems, such as those with high blood pressure or diabetes and those with a blood relative with chronic kidney disease. Chronic kidney disease may also be identified when it leads to one of its recognized complications, such as cardiovascular disease, anemia or pericarditis. It is differentiated from acute kidney disease in that the reduction in kidney function must be present for over 3 months.
There is a strong association between both acute and chronic dysfunction of the heart and kidneys with respect to morbidity and mortality. The complex interrelationships of longitudinal changes in both organ systems have been difficult to describe and fully understand due to a lack of categorization of the common clinical scenarios where these phenomena are encountered. Thus, cardiorenal syndromes (CRSs) have been subdivided into five syndromes which represent clinical vignettes in which both the heart and the kidney are involved in bidirectional injury and dysfunction via a final common pathway of cell-to-cell death and accelerated apoptosis mediated by oxidative stress. Types 1 and 2 involve acute and chronic cardiovascular disease (CVD) scenarios leading to acute kidney injury (AKI) or accelerated chronic kidney disease (CKD). Types 3 and 4 describe AKI and CKD, respectively, leading primarily to heart failure, although it is possible that acute coronary syndromes, stroke, and arrhythmias could be CVD outcomes in these forms of CRS. Finally, CRSs type 5 describe a systemic insult to both heart and the kidneys, such as sepsis, where both organs are injured simultaneously in persons with previously normal heart and kidney function at baseline. Both blood and urine biomarkers, including the assessment of catalytic iron, a critical element to the generation of oxygen-free radicals and oxidative stress, are reviewed in this paper. Cardiorenal syndromes (CRS) have been subclassified as five defined entities which represent clinical circumstances in which both the heart and the kidney are involved in a bidirectional injury and dysfunction via a final common pathway of cell-to-cell death and accelerated apoptosis mediated by oxidative stress. Types 1 and 2 involve acute and chronic cardiovascular disease (CVD) scenarios leading to acute kidney injury or accelerated chronic kidney disease. Types 2 and 3 describe acute and chronic kidney disease leading primarily to heart failure, although it is possible that acute coronary syndromes, stroke, and arrhythmias could be CVD outcomes in these forms of CRS. Finally, CRS type 5 describes a simultaneous insult to both heart and kidneys, such as sepsis, where both organs are injured simultaneously. Both blood and urine biomarkers are reviewed in this paper and offer a considerable opportunity to enhance the understanding of the pathophysiology and known epidemiology of these recently defined syndromes. A growing number of patients are recognised to have chronic kidney disease (CKD). However, only a minority will progress to end-stage renal disease requiring dialysis or transplantation. Currently available diagnostic and staging tools frequently fail to identify those at higher risk of progression or death. Furthermore within specific disease entities there are shortcomings in the prediction of the need for therapeutic interventions or the response to different forms of therapy. Kidney and urine proteomic biomarkers are considered as promising diagnostic tools to predict CKD progression early in diabetic nephropathy, facilitating timely and selective intervention that may reduce the related health-care expenditures. However, independent groups have not validated these findings and the technique is not currently available for routine clinical care. Furthermore, there are gaps in our understanding of predictors of progression or need for therapy in non-diabetic CKD. Presumably, a combination of tissue and urine biomarkers will be more informative than individual markers. This review identifies clinical questions in need of an answer, summarises current information on proteomic biomarkers and CKD, and describes the European Kidney and Urine Proteomics initiative that has been launched to carry out a clinical study aimed at identifying urinary proteomic biomarkers distinguishing between fast and slow progressors among patients with biopsy-proven primary glomerulopathies. INTRODUCTION: Conventional markers of acute kidney injury (AKI) lack diagnostic accuracy and are expressed only late after cardiac surgery with cardiopulmonary bypass (CPB). Recently, interest has focused on hepcidin, a regulator of iron homeostasis, as a unique renal biomarker. METHODS: We studied 100 adult patients in the control arm of a randomized, controlled trial http://www.clinicaltrials.gov/NCT00672334 who were identified as being at increased risk of AKI after cardiac surgery with CPB. AKI was defined according to the Risk, Injury, Failure, Loss, End-stage renal disease classification of AKI classification stage. Samples of plasma and urine were obtained simultaneously (1) before CPB (2) six hours after the start of CPB and (3) twenty-four hours after CPB. Plasma and urine hepcidin 25-isoforms were quantified by competitive enzyme-linked immunoassay. RESULTS: In AKI-free patients (N = 91), urine hepcidin concentrations had largely increased at six and twenty-four hours after CPB, and they were three to seven times higher compared to patients with subsequent AKI (N = 9) in whom postoperative urine hepcidin remained at preoperative levels (P = 0.004, P = 0.002). Furthermore, higher urine hepcidin and, even more so, urine hepcidin adjusted to urine creatinine at six hours after CPB discriminated patients who did not develop AKI (area under the curve (AUC) receiver operating characteristic curve 0.80 [95% confidence interval (95% CI) 0.71 to 0.87] and 0.88 [95% CI 0.78 to 0.97]) or did not need renal replacement therapy initiation (AUC 0.81 [95% CI 0.72 to 0.88] 0.88 [95% CI 0.70 to 0.99]) from those who did. At six hours, urine hepcidin adjusted to urine creatinine was an independent predictor of ruling out AKI (P = 0.011). Plasma hepcidin did not predict no development of AKI. The study findings remained essentially unchanged after excluding patients with preoperative chronic kidney disease. CONCLUSIONS: Our findings suggest that urine hepcidin is an early predictive biomarker of ruling out AKI after CPB, thereby contributing to early patient risk stratification. Acute kidney injury (AKI) in hospitalized patients is independently associated with increased morbidity and mortality in pediatric and adult populations. Continued reliance on serum creatinine and urine output to diagnose AKI has resulted in our inability to provide successful therapeutic and supportive interventions to prevent and mitigate AKI and its effects. Research efforts over the last decade have focused on the discovery and validation of novel urinary biomarkers to detect AKI prior to a change in kidney function and to aid in the differential diagnosis of AKI. The aim of this article is to review the AKI biomarker literature with a focus on the context in which they should serve to add to the clinical context facing physicians caring for patients with, or at-risk for, AKI. The optimal and appropriate utilization of AKI biomarkers will only be realized by understanding their characteristics and placing reasonable expectations on their performance in the clinical arena. CONTEXT: Kidney-related pathologies have increasing prevalence rates, produce a considerable ficial burden, and are characterized by elevated levels of oxidative stress (OS). OBJECTIVE: This review examines relationships between chronic kidney disease (CKD) and markers of OS and antioxidant status (AS). METHODS: A systematic review of MEDLINE-indexed clinical trials, randomized controlled trials and comparative studies that examined OS and AS was performed. RESULTS AND CONCLUSION: Several markers emerged as well-suited indicators of OS and AS in CKD: malondialdehyde, F2-isoprostanes, lipid hydroperoxides, asymmetric dimethylarginine, 8-oxo-7,8-dihydro-2'-deoxyguanosine, protein carbonyls, advanced oxidation protein products and glutathione-related activity. Novel biomarkers may improve our ability to predict which patients with chronic kidney disease (CKD) are at higher risk for progressive loss of renal function. Here, we assessed the performance of urine neutrophil gelatinase-associated lipocalin (NGAL) for outcome prediction in a diverse cohort of 3386 patients with CKD in the Chronic Renal Insufficiency Cohort study. In this cohort, the baseline mean estimated glomerular filtration rate (eGFR) was 42.4 ml/min per 1.73 m(2), the median 24-h urine protein was 0.2 g/day, and the median urine NGAL concentration was 17.2 ng/ml. Over an average follow-up of 3.2 years, there were 689 cases in which the eGFR was decreased by half or incident end-stage renal disease developed. Even after accounting for eGFR, proteinuria, and other known CKD progression risk factors, urine NGAL remained a significant independent risk factor (Cox model hazard ratio 1.70 highest to lowest quartile). The association between baseline urine NGAL levels and risk of CKD progression was strongest in the first 2 years of biomarker measurement. Within this time frame, adding urine NGAL to a model that included eGFR, proteinuria, and other CKD progression risk factors led to net reclassification improvement of 24.7%, but the C-statistic remained nearly identical. Thus, while urine NGAL was an independent risk factor of progression among patients with established CKD of diverse etiology, it did not substantially improve prediction of outcome events. BACKGROUND: Chronic kidney disease (CKD) affects up to 16% of the adult population and is associated with significant morbidity and mortality. People at highest risk from progressive CKD are defined by a sustained decline in estimated glomerular filtration rate (eGFR) and/or the presence of significant albuminuria/proteinuria and/or more advanced CKD. Accurate mapping of the bio-clinical determits of this group will enable improved risk stratification and direct the development of better targeted management for people with CKD. METHODS/DESIGN: The Renal Impairment In Secondary Care study is a prospective, observational cohort study, patients with CKD 4 and 5 or CKD 3 and either accelerated progression and/or proteinuria who are managed in secondary care are eligible to participate. Participants undergo a detailed bio-clinical assessment that includes measures of vascular health, periodontal health, quality of life and socio-economic status, clinical assessment and collection of samples for biomarker analysis. The assessments take place at baseline, and at six, 18, 36, 60 and 120 months; the outcomes of interest include cardiovascular events, progression to end stage kidney disease and death. DISCUSSION: The determits of progression of chronic kidney disease are not fully understood though there are a number of proposed risk factors for progression (both traditional and novel). This study will provide a detailed bio-clinical phenotype of patients with high-risk chronic kidney disease (high risk of both progression and cardiovascular events) and will repeatedly assess them over a prolonged follow up period. Recruitment commenced in Autumn 2010 and will provide many outputs that will add to the evidence base for progressive chronic kidney disease. BACKGROUND: The Canadian Study of Prediction of Death, Dialysis and Interim Cardiovascular Events (CanPREDDICT) is a large, prospective, pan-Canadian, cohort study designed to improve our understanding of determits of renal and cardiovascular (CV) disease progression in patients with chronic kidney disease (CKD). The primary objective is to clarify the associations between traditional and newer biomarkers in the prediction of specific renal and CV events, and of death in patients with CKD managed by nephrologists. This information could then be used to better understand biological variation in outcomes, to develop clinical prediction models and to inform enrolment into interventional studies which may lead to novel treatments. METHODS/DESIGNS: Commenced in 2008, 2546 patients have been enrolled with eGFR between 15 and 45 ml/min 1.73m2 from a representative sample in 25 rural, urban, academic and non academic centres across Canada. Patients are to be followed for an initial 3 years at 6 monthly intervals, and subsequently annually. Traditional biomarkers include eGFR, urine albumin creatinine ratio (uACR), hemoglobin (Hgb), phosphate and albumin. Newer biomarkers of interest were selected on the basis of biological relevance to important processes, commercial availability and assay reproducibility. They include asymmetric dimethylarginine (ADMA), N-terminal pro-brain natriuretic peptide (NT-pro-BNP), troponin I, cystatin C, high sensitivity C-reactive protein (hsCRP), interleukin-6 (IL6) and transforming growth factor beta 1 (TGFβ1). Blood and urine samples are collected at baseline, and every 6 monthly, and stored at -80°C. Outcomes of interest include renal replacement therapy, CV events and death, the latter two of which are adjudicated by an independent panel. DISCUSSION: The baseline distribution of newer biomarkers does not appear to track to markers of kidney function and therefore may offer some discriminatory value in predicting future outcomes. The granularity of the data presented at baseline may foster additional questions.The value of the cohort as a unique resource to understand outcomes of patients under the care of nephrologists in a single payer healthcare system cannot be overstated. Systematic collection of demographic, laboratory and event data should lead to new insights. The mean age of the cohort was 68 years, 90% were Caucasian, 62% were male, and 48% had diabetes. Forty percent of the cohort had eGFR between 30-45 mL/min/1.73m², 22% had eGFR values below 20 mL/min/1.73m²; 61% had uACR < 30. Serum albumin, hemoglobin, calcium and 25-hydroxyvitamin D (25(OH)D) levels were progressively lower in the lower eGFR strata, while parathyroid hormone (PTH) levels increased. Cystatin C, ADMA, NT-proBNP, hsCRP, troponin I and IL-6 were significantly higher in the lower GFR strata, whereas 25(OH)D and TGFβ1 values were lower at lower GFR. These distributions of each of the newer biomarkers by eGFR and uACR categories were variable. In the current study, we measured urinary angiotensinogen (AGT) through enzyme-linked immunoadsordent assay (ELISA) and analyzed its correlation with intrarenal renin-angiotensin system (RAS) activity in 128 chronic kidney disease (CKD) patients. Urinary and plasma renin activity, AGT, angiotensin II (Ang II) and aldosterone levels were also measured by radioimmunoassay (RIA) or ELISA in these participants. Further, the expression level of intrarenal renin, AGT, Ang II and Ang II receptors were examined by immunohistochemistry staining (IHCS) in 72 CKD patients. Their correlations with urinary AGT were also analyzed. We found that the urinary AGT level was positively correlated with hypertension (ρ = 0.28, P < 0.01), urinary protein (r = 0.38, P < 0.01), urinary Ang II (r = 0.29, P < 0.05), urinary type IV collagen (Col IV) (r = 0.56, P < 0.01), and was negatively correlated with estimated glomerular filtration rate (eGFR) (r = -0.28, P < 0.01), urinary sodium (r = -0.22, P < 0.05) and serum AGT (r = -0.27, P < 0.01). Multiple regression analysis indicated low serum AGT (P < 0.01), high urinary protein (P < 0.01), high urinary Ang II (P < 0.05) and high urinary Col IV (P < 0.01) were correlated significantly with high urinary AGT. Urinary AGT level was positively correlated with intrarenal expression level of AGT (ρ = 0.46, P < 0.01), Ang II (ρ = 0.56, P < 0.01) and Ang II type 1 receptor (ρ = 0.32, P < 0.01), as detected by IHCS. Together, these data suggest that urinary AGT might be a potential biomarker of intrarenal RAS and Ang II activities in CKD patients. BACKGROUND: The inclining incidence of chronic kidney disease which has led to high mortality and immense medical burden over the past decades has become a distressing concern in epidemiology. Unfortunately, the number of biomarkers that allow the monitoring of chronic kidney disease (CKD) is limited. Neutrophil gelatinase-associated lipocalin (NGAL) is an emerging biomarker which has been shown to be able to diagnose kidney injuries. METHODS: Eighty-one nondiabetic patients with chronic kidney disease, stage 2 to 5, were recruited for this study, and 17 healthy volunteers with eGFR greater than 90 mL/minute/1.73m(2) were selected as the control group. RESULTS: Our study demonstrated that the pNGAL level is elevated during CKD, and the pNGL level has a strong correlation with the concentration of sCr and eGFR. CONCLUSIONS: Plasma neutrophil gelatinase-associated lipocalin is a potent tool in the diagnosis of chronic kidney diseases and is shown to have high correlation with serum creatinine and estimated glomerular filtration rate. Inflammation is a common phenotype for cardiometabolic disorders. In this study, we attempted to investigate inter-relationships between metabolic syndrome (MetS), C-reactive protein (an inflammatory biomarker) and chronic kidney disease (CKD). We performed a cross-sectional analysis of data from a representative sample of 4425 Chinese adults in Taiwan. The MetS was defined by a unified criteria set by several major organizations. A CKD event was defined as an estimated glomerular filtration rate (eGFR) <60 mL/min per 1.73 m(2). Additionly, a CRP cutpoint of 3 mg/L was used to differentiate high and low CRP levels. Overall, 1000 participants had MetS, resulting in a prevalence rate of 22.6%. High CRP level was noted in 782 (17.6%) subjects. In addition, a total of 508 (11.5%) persons qualified as having CKD. Subjects with the MetS had 1.55-fold [95% confidence interval (CI), 1.03-2.32] increased odds of CKD compared with their counterparts without the MetS after multiple adjustments. In addition, there was a significantly graded relationship between increasing levels of serum CRP and prevalent CKD (p for trend = 0.001). Participants in the highest category of serum CRP had a significantly elevated odds of CKD as compared with those in the lowest category [odds ratio (OR), 1.60; 95% CI, 1.21-2.12]. However, there was no interaction in excess of additive scale between the presence of MetS and high CRP level (p = 0.83). These findings suggest that MetS and high CRP were independently associated with increased prevalence of CKD in Chinese adults. Liver-type fatty acid binding protein (L-FABP) is a 14kDa protein found in the cytoplasm of human renal proximal tubules. Fatty acids are bound with L-FABP and transported to the mitochondria or peroxisomes, where fatty acids are beta-oxidized, and this may play a role in fatty acid homeostasis. Moreover, L-FABP has high affinity and capacity to bind long-chain fatty acid oxidation products, and may be an effective endogenous antioxidant. Renal L-FABP is rarely expressed in the kidneys of rodents. In order to evaluate the pathological dynamics of renal L-FABP in kidney disease, human L-FABP chromosomal transgenic mice were generated. Various stress, such as massive proteinuria, hyperglycemia, hypertension, and toxins overloaded in the proximal tubules were revealed to up-regulate the gene expression of renal L-FABP and increase the excretion of L-FABP derived from the proximal tubules into urine. In clinical studies of chronic kidney disease (CKD), urinary L-FABP accurately reflected the degree of tubulointerstitial damage and correlated with the rate of CKD progression. Furthermore, a multicenter trial has shown that urinary L-FABP is more sensitive than urinary protein in predicting the progression of CKD. With respect to diabetic nephropathy and acute kidney disease (AKI), urinary L-FABP is an early diagnostic of kidney disease or a predictive marker for renal prognosis. After many clinical studies, urinary L-FABP was approved as a new tubular biomarker promulgated by the Ministry of Health, Labour and Welfare in Japan. BACKGROUND: Urine albumin is the primary biomarker for detection and monitoring of kidney damage. Because fixed decision criteria are used to identify patients with increased values, we investigated if commonly used routine measurement procedures gave comparable results. METHODS: Results from 17 commercially available urine albumin measurement procedures were investigated vs an isotope dilution mass spectrometry (IDMS) procedure. Nonfrozen aliquots of freshly collected urine from 332 patients with chronic kidney disease, diabetes, cardiovascular disease, and hypertension were distributed to manufacturers to perform urine albumin measurements according to the respective instructions for use for each procedure. Frozen aliquots were used for measurements by the IDMS procedure. An error model was used to determine imprecision and bias components. RESULTS: Median differences between the largest positive and negative biases vs IDMS were 45%, 37%, and 42% in the concentration intervals of 12-30 mg/L, 31-200 mg/L, and 201-1064 mg/L, respectively. Biases varied with concentration for most procedures and exceeded ± 10% over the concentration interval for 14 of 16 quantitative procedures. Mean biases ranged from -35% to 34% at 15 mg/L. Dilution of samples with high concentrations introduced bias for 4 procedures. The combined CV was >10% for 5 procedures. It was not possible to estimate total error due to dependence of bias on concentration. CVs for sample-specific influences were 0% to 15.2%. CONCLUSIONS: Bias was the domit source of disagreement among routine measurement procedures. Consequently, standardization efforts will improve agreement among results. Variation of bias with concentration needs to be addressed by manufacturers. In patients with resistant hypertension (RH) we investigated the importance of urinary neutrophil gelatinase-associated lipocalin (uNGAL- a chemiluminescent microparticle immunoassay (CMIA) method became using (Abbott Diagnostics) for the measurement of NGAL in urine samples) and incidence of chronic kidney disease using the Modification of Diet in Renal Disease Study (MDRD) and Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equations in estimating glomerular filtration rate (eGFR) based on standardised serum creatinine method traceable to isotope dilution mass spectrometry (IDMS) method. It would have been difficult to predict that levels of these biomarker would perform better organ damage than traditional measurements of kidney function such as standardised serum creatinine, MDRD, or CKD-EPI equations in special population such as RH. Serum creatinine concentrations were measured in 50 patients (24M:26F from RH Registar in Clinical Hospital Merkur) by the kinetic Jaffe method. There were no significant differences between the GFR values derived by MDRD and CKD-EPI equations in the group of patients with RH. 62% of patients have eGFR > 60 mL/minl/1.73 m2, while a 38% of patients have eGFR < 60 mL/min/1.73 m2. The measurement of NGAL in urine samples of 40 patients with RH showed no difference and seems to be of no use in further determination of renal impairement. Higher value of uNGAL in some resistant hypertension patients could have link in the repair stage after AKI and would reveal pathways that could link AKI and CKD. End-stage renal disease (ESRD) requires for its treatment permanent dialysis or kidney transplantation (KT). KT is the best clinical treatment, however, the early function of the allograft varies depending on multiple factors associated with cold ischemia time (CIT) and the allograft rejection process. It is known that serum creatinine is an insensitive and late marker for predicting graft recovery after KT, mainly in patients with delayed graft function (DGF). Neutrophil gelatinase-associated lipocalin (NGAL) is produced in the distal nephron and it is one of the most promising novel biomarkers for acute kidney injury (AKI) and chronic kidney disease (CKD). NGAL has been proposed to be a predictor of organ recovery from DGF after KT from donors after cardiac death. Because nonrenal diseases can also induce NGAL, more information is necessary to validate the sensitivity and specificity of urine and plasma NGAL in clinical samples. The exosomes are vesicles released into the urine from the kidney epithelium and they have been proposed as better source to explore as biomarker of renal dysfunction. The molecular composition of the urinary exosomes could be representative of the physiological or physiopathologic condition of the urinary system. We propose that determination of NGAL in urinary exosomes is a better predictor of kidney dysfunction after KT than other urinary fractions. We analyzed 15 kidney allograft recipients, with a mean age of 36 years (range, 16-60 years) and 75% were male: 11 living donors (LD) and 4 deceased donors (DD). The average length of CIT was 14 hours in DD and less than 1 hour in LD. Three patient developed DGF. Using Western blot analysis, NGAL was detectable in the cellular and exosomal fraction of the urine. The exosomes expressed higher levels of NGAL than the cellular fraction. The expression of NGAL was observed from the first day after transplantation. In the cellular fraction of the urine, no significant differences of NGAL were observed between the patients. However, the median of NGAL expression in the exosomes fraction was significantly higher in DD patient, from the first day after KT (P < .05). Moreover, we noticed that NGAL expression in exosomes remained elevated in the patients with DGF compared with non-DGF patients (P < .05). Considering the highest abundance of NGAL in the urinary exosomes and its correlation with DGF patients, we suggest the exosomal fraction as a more sensitive substrate to evaluate early biomarkers of DGF after KT.
What is being measured with an accelerometer in back pain patients
Accelerometer assessment measuring overall physical activity (PAL), constant strain postures (CSP), standing time (ST) and lying time (LT)... The following parameters of physical activity were recorded: time upright (standing or walking), time standing, time walking, and step count.
We studied the temporal relationship between pain and activity in patients with acute or chronic low back pain. We studied 15 patients with acute low back pain and 15 patients with chronic low back pain over 3 wk. The activity levels were collected automatically using a wrist accelerometer and were sampled every minute. The pain levels were recorded at least every 90 min using a pocket-sized electronic diary. The time series from each patient were then analyzed using the cross-correlation function at various time offsets. We found that during the first 7 days of acute low back pain, there was a significant (P < 0.01) degree of cross-correlation between activity and pain. On average, pain followed activity by approximately 30 min. As these patients improved and reported less pain, the relationship between activity and pain disappeared. There was no such relationship at any point among the patients with chronic low back pain. BACKGROUND: In LBP patients, the relationship between pain and physical activity remains unclear. Whereas a negative relationship between pain and self-reported physical activity was found, this relation disappeared in the case of overt behavioral data (e.g., accelerometer). Cognitive-behavioral models of the development of chronic pain suggest subgroups with signs of physical underuse and overuse. AIMS: To examine if patients with pain-related adaptive, endurance and fear-avoidance coping differ in pain, self-reported physical function and overt physical activity 6 months after disc surgery. METHODS: 24 patients completed questionnaires (Von Korff chronic pain grade (CPG), Kiel pain inventory (KPI), Funktionsfragebogen Hannover-Rücken FFbH-R) and underwent an 8-h accelerometer assessment in their daily life (physical activity level (PAL), number of constant postures (CP)). The KPI differed between adaptive coping (AC) (N=9), fear avoidance coping (FAC) (N=1) and endurance coping (EC) (N=14). RESULTS: In the whole group, pain intensity was negative related to self-reported physical activity whereas PAL and CP displayed no correlation with pain. EC patients showed significantly higher pain scores and lower self-reported physical functioning compared to AC but the same level of PAL and furthermore, a significantly higher number of CPs in daily life. The visual inspection of the FAC patient revealed also high pain, low physical functioning and low overt physical activity. CONCLUSIONS: The assessment of pain-related coping modes yielded an important differentiation between subgroups of LBP patients 6 months after surgery. Endurance copers displayed signs of overuse in their daily behavior in spite of pain than adaptive copers. The one fear avoidance coper tends to do less physical activity in the sense of underuse. There may be a relationship between sleep and pain in patients with chronic back pain. We collected day-time pain and nighttime activity data from 18 patients diagnosed with chronic back pain. The patients were followed for 6 days and 5 nights. Pain levels were collected every 90 min between 0800 hours and 2,200 hours using a computerized electronic diary. Activity levels were collected using a wrist accelerometer (Actiwatch AW-64). The Actiwatch sampled activity counts every 1 min. Patients were asked to wear the Actiwatch on their non-domit arm. The pain level measurements were interpolated using cubic splines. A mean pain level was calculated for each period 0800 hours to 2,200 hours as well as for the 6-day period. The difference between the mean pain levels for the 6-day period and each 0800 hours to 2,200 hours period was calculated for each patient. Nighttime activity data were analyzed using the Actiwatch Sleep Analysis software. Correlations were calculated between the Actiwatch Sleep Analysis variables and the mean pain level differences for each patient and period. The correlation analysis was performed with SPSS 7.5. We were unable to show any significant relationships.A different approach to analyze the data was used. A Self-Organizing Map (SOM) Neural Network was trained using the original nighttime activity level time series from 10 randomly selected patients. Recall was then performed on all the activity level data. Correlations were calculated between the pain level variance for the 6-day period for each patient and the corresponding difference in the SOM output coordinates. The correlation was found to be r = 0.73, p < 0.01). We conclude that daytime pain levels are not directly correlated with sleep in the following night and that sleep is not directly correlated with daytime pain levels on the following day in this group of patients. There appears to be a correlation between the difference in nighttime activity levels and patterns and the daytime pain variance. Patients who experience large fluctuations in daytime pain levels also show a higher variability in their nighttime activity levels and patterns. Even though we were unable to show a direct relationship between daytime pain and sleep, it may be reasonable to assume that better pain control resulting in less daytime pain fluctuations can provide more stable nighttime activity levels and patterns in this limited group of patients. By using a neural network model, we were able to extract information from the nighttime activity levels even though a traditional statistical analysis was unsuccessful. BACKGROUND: Normalization of activities in daily living is an important goal in rehabilitation treatment of chronic lower back pain (CLBP) patients. Clinicians indicate that CLBP patients often show deconditioning but also CLBP patients who seem to be too active are seen. The objective of the present cross-sectional study was to gain more insight into the daily activity pattern of CLBP patients compared to controls, using accelerometry. METHODS: Daily activities were assessed by measuring body movement with a tri-axial accelerometer that was worn for seven consecutive days during waking hours. Measurements were performed in the daily environment (in-doors and out-doors) of the participant. Differences between activity level, time of day and work status were tested. RESULTS: Data were obtained from 29 CLBP patients and 20 controls. Results show that the overall activity levels of patients (mean 0.75; SD 0.43) are not significantly different from those of controls (mean 0.71; SD 0.44). However, patients show significantly higher activity levels in the morning (p<0.001) and significantly lower activity levels in the evening (p<0.01) compared to controls. No significant differences in activity levels were found between leisure time and working days within either group; furthermore no significant differences in activity levels were found between patients with different work status. CONCLUSION: Overall activity levels do not differ significantly between CLBP patients and controls, but the distribution of activities over the day differs significantly. BACKGROUND: The present study aims to determine the time spent in different static trunk postures during a typical working day of workers in a special school for the severe handicaps. METHODS: Eighteen workers with low back pain (LBP) and fifteen asymptomatic workers were recruited. A cross-sectional design was employed to study the time spent in different static trunk postures which was recorded by a biaxial accelerometer attached to the T12 level of the back of the subjects. RESULTS: The results of ANCOVA revealed that subjects with LBP spent significantly longer percentage of time in static trunk posture when compared to normal (p < 0.05). It was also shown that they spent significantly longer time in trunk flexion for more than 10 degrees (p < 0.0125). CONCLUSION: An innovative method has been developed for continuous tracking of spinal posture, and this has potential for widespread applications in the workplace. The findings of the present investigation suggest that teachers in special schools are at increased risk of getting LBP. In order to minimise such risk, frequent postural change and awareness of work posture are recommended. The aim of this cross-sectional pilot-study was to investigate the relationship between psychological distress and free-living physical activity (PA) in individuals with chronic low back pain (CLBP). Thirty-eight participants with non-specific CLBP (29=distressed; 9=non-distressed) were recruited. PA levels were measured using an accelerometer (activPAL activity monitor) over a one week period. The following parameters of physical activity were recorded: time upright (standing or walking), time standing, time walking, and step count. Psychological distress was assessed using a modified version of the distress risk assessment method (DRAM) which is a combination of somatic anxiety and depressive symptoms. The Distressed group spent significantly less time upright over a mean 24h day (-1.47h, 95% CI -2.70 to -0.23h, p<0.05), attributable to 1.01h less standing and 0.46h less walking. Depressive symptoms were a statistically significant independent predictor of time upright (beta=-0.49, p<0.05). This pilot-study found that individuals with CLBP and elevated levels of distress spend less time upright than their non-distressed counterparts. Clinically, when treating individuals with CLBP and elevated distress levels, free-living PA may be low and interventions aimed at increasing upright activity may be appropriate. In patients with low back pain (LBP), physical functioning may be negatively influenced by both expectations on pain and pain-related fear. It is unclear whether these factors influence both physical functioning in the laboratory as well as in daily life. The aim of this study was to test if a combination of persistent overprediction of pain and fear of movement predicts lab-based performance and whether these factors are relevant for predicting daily-life functioning. One hundred and twenty four patients with subacute LBP performed a laboratory-based performance test twice. Maximum voluntary contraction, pre-test pain expectations, perceived pain during testing and fear of movement were measured. Patients were classified as correct or incorrect predictors, based on differences between expected and perceived pain on the second attempt. Next, physical activity in daily life was measured with an accelerometer. In explaining physical functioning in the laboratory and in daily life an interaction effect between fear and pain prediction was observed. In overpredictors, fear was negatively associated with lab-based performance (beta=-0.48, p<0.01), and positively associated with daily-life functioning (beta=0.50, p<0.05). No significant association between fear and performance or daily-life functioning were found in correct predictors. In contrast to correct predictors, in overpredictors lab-based performance and daily-life functioning was additionally explained by fear of movement. Thus it appears that fear of movement is only predictive of performance in patients with LBP who simultaneously overpredict the consequences of movements in terms of painfulness. Patients with chronic pain may have difficulties estimating their own physical activity level in daily life. Pain-related factors such as depression and pain intensity may affect a patients' ability to estimate their own daily life activity level. This study evaluates whether patients with Chronic Low Back Pain (CLBP) who are more depressed and/or report more pain indeed have a lower objectively assessed daily life activity level or whether they only perceive their activity level as lower. Patients with CLBP were included in a cross-sectional study. During 14days physical activity in daily life was measured, with both an electronic diary and an accelerometer. Multilevel analyses were performed to evaluate whether a higher level of depression and/or pain intensity was associated with a lower objectively assessed activity level or the discrepancy between the self-reported and objectively assessed daily life activity levels. Results, based on 66 patients with CLBP (mean RDQ score 11.8), showed that the objectively assessed daily life activity level is not associated with depression or pain intensity. There was a moderate association between the self-reported and objectively assessed activity levels (beta=0.39, p<0.01). The discrepancy between the two was significantly and negatively related to depression (beta=-0.19, p=0.01), indicating that patients who had higher levels of depression judged their own activity level to be relatively low compared to their objectively assessed activity level. Pain intensity was not associated with the perception of a patient's activity level (beta=0.12, ns). OBJECTIVE: To compare self-report measures of daily activities with objective activity data to determine whether patients with chronic lower back pain report their activity levels as accurately as controls do. DESIGN: A cross-sectional study was performed in patients and controls. SETTING: The study was carried out in the daily environment of the subjects. SUBJECTS: Thirty-two chronic lower back pain patients with symptoms more than three months and 20 healthy controls from the Netherlands, aged 18-65 years. MAIN MEASURES: A tri-axial accelerometer was worn for five weekdays and the Baecke Physical Activity Questionnaire was filled in. Pearson's correlation was calculated to get insight in the awareness of patients and controls. Comparisons of the relationship between the objective and subjective scores of each individual patient with those of the group of controls were used to allocate each patient into subgroups: overestimators, underestimators and aware patients. Physical and psychological characteristics of these groups were explored. RESULTS: Patients showed weak correlations between the objective and subjective scores of physical activity and appear to have problems in estimating their activity levels (r = -0.27), in contrast to controls who showed strong correlations between the objective and subjective scores (r = 0.66). Comparison of the individual relationships of patients with those of controls showed that 44% of the patients were not aware of their activity level. There were relatively more underestimators (30%) than overestimators (14%). Physical characteristics between the three groups tended to be different. CONCLUSIONS: Patient self-reports about their activity level are relatively inaccurate when compared to objective measurements. PURPOSE: This study examines the relationship between low back pain, disability and fatigue and overt physical activity with respect to fear-avoidance and endurance-related subgroups. METHOD: 49 patients completed questionnaires (Pain, Disability, Fatigue, Depression, Pain-responses pattern) 6 months after lumbar disc surgery and underwent an 8-hour accelerometer assessment measuring overall physical activity (PAL), constant strain postures (CSP), standing time (ST) and lying time (LT). Four subgroups, representing patterns of distress-endurance (DER), eustress-endurance (EER), fear-avoidance (FAR) and adaptive responses (AR) due to the avoidance-endurance model of pain-regulation were investigated. RESULTS: Multivariate analyses of covariance revealed significantly higher pain, disability and fatigue in FAR compared to AR patients and, as expected lower PAL and CSP in FAR than in endurance patients. Both endurance groups revealed higher pain accompanied by higher accelerometer-based physical activity (PAL, CSP) than AR and FAR patients. Most of the subgroup differences displayed moderate to high effect sizes. CONCLUSIONS: The results indicate different pathways to chronic pain and disability with physical underuse in FAR patients and overuse/overload in endurance patients suggesting the need for individually targeted cognitive-behavioral treatments in the maladaptive groups. Implications for Rehabilitation Improving the return to a normal physical activity level is an important goal for the rehabilitation of patients after lumbar disc surgery. Different pathways to chronic pain and disability with physical underuse in fear-avoidance patients and overuse in endurance patients should be considered. Different pain-related pain response pattern, based on the avoidance-endurance model, indicate the need for individual targeting of rehabilitation programs.
List the releases of JASPAR database
JASPAR, JASPAR CORE, JASPAR FAM, JASPAR phyloFACTS, JASPAR 2008 update, JASPAR 2010, JASPAR 2014.
The analysis of regulatory regions in genome sequences is strongly based on the detection of potential transcription factor binding sites. The preferred models for representation of transcription factor binding specificity have been termed position-specific scoring matrices. JASPAR is an open-access database of annotated, high-quality, matrix-based transcription factor binding site profiles for multicellular eukaryotes. The profiles were derived exclusively from sets of nucleotide sequences experimentally demonstrated to bind transcription factors. The database is complemented by a web interface for browsing, searching and subset selection, an online sequence analysis utility and a suite of programming tools for genome-wide and comparative genomic analysis of regulatory regions. JASPAR is available at http://jaspar. cgb.ki.se. JASPAR is a popular open-access database for matrix models describing DNA-binding preferences for transcription factors and other DNA patterns. With its third major release, JASPAR has been expanded and equipped with additional functions aimed at both casual and power users. The heart of the JASPAR database-the JASPAR CORE sub-database-has increased by 12% in size, and three new specialized sub-databases have been added. New functions include clustering of matrix models by similarity, generation of random matrices by sampling from selected sets of existing models and a language-independent Web Service applications programming interface for matrix retrieval. JASPAR is available at http://jaspar.genereg.net. JASPAR (http://jaspar.genereg.net) is the largest open-access database of matrix-based nucleotide profiles describing the binding preference of transcription factors from multiple species. The fifth major release greatly expands the heart of JASPAR-the JASPAR CORE subcollection, which contains curated, non-redundant profiles-with 135 new curated profiles (74 in vertebrates, 8 in Drosophila melanogaster, 10 in Caenorhabditis elegans and 43 in Arabidopsis thaliana; a 30% increase in total) and 43 older updated profiles (36 in vertebrates, 3 in D. melanogaster and 4 in A. thaliana; a 9% update in total). The new and updated profiles are mainly derived from published chromatin immunoprecipitation-seq experimental datasets. In addition, the web interface has been enhanced with advanced capabilities in browsing, searching and subsetting. Finally, the new JASPAR release is accompanied by a new BioPython package, a new R tool package and a new R/Bioconductor data package to facilitate access for both manual and automated methods.
List symptoms of the IFAP syndrome.
The IFAP syndrome is a rare X-linked genetic disorder characterized by the triad of follicular ichthyosis, atrichia, and photophobia.
We report on a boy with short stature, mental retardation, seizures, follicular ichthyosis, generalized alopecia, hypohydrosis, enamel dysplasia, photophobia, congenital aganglionic megacolon, inguinal hernia, vertebral, renal and other anomalies, and a normal chromosome constitution. The clinical findings include all the features that dermotrichic and ichthyosis follicularis-alopecia-photophobia (IFAP) syndrome have in common and in addition those that characterize IFAP syndrome (photophobia, recurrent respiratory infections, etc.), those that are present only in dermotrichic syndrome (nail anomalies, hypohydrosis, megacolon, vertebral defects, etc.) and additional ones (enamel dysplasia, renal anomalies, inguinal hernia, etc.). Two maternal uncles were referred as being affected by alopecia and ichthyosis suggesting X-linked recessive transmission. Various hypotheses concerning the relationship between the 2 syndromes and the present case are discussed. We describe an 18-month-old male infant suffering from the ichthyosis follicularis, atrichia, and photophobia (IFAP) syndrome and further delineate the clinical phenotype. Severe retardation of growth and psychomotor development, chill-like seizures, bronchial asthma, urticaria, a proneness to skin infections and transient nail dystrophy observed in our patient are non-obligatory manifestations of this disorder. Histological examination of the atrichia revealed poorly developed, shortened hair follicles and a complete absence of sebaceous glands. The sex ratio of published cases suggests an X-linked recessive inheritance. The marked clinical variability of the IFAP syndrome might be the expression of a contiguous gene defect. A diagnosis of IFAP (ichthyosis follicularis with atrichia and photophobia) syndrome was established in a 1-year-old boy with congenital hairlessness, generalized ichthyotic skin changes with follicular hyperkeratoses, and photophobia. IFAP syndrome is considered to be an X-linked recessive trait. The phenotype present in female carriers has so far not been delineated. A 2-year-old sister had atrophoderma and ichthyotic skin lesions arranged in a linear pattern and a large noncicatrical bald patch on her scalp. Similarly, the mother had linear lesions of scaling and atrophy as well as circumscribed hairless areas involving the scalp, the axillary region, and the lower legs. Sweat testing by means of iodine starch-reaction visualized hypohidrotic linear lesions corresponding to the areas of hyperkeratosis and atrophy. In both mother and daughter the lesions followed the lines of Blaschko, whereas the boy was diffusely affected. Family history showed that the boy's maternal uncle who had died at age 1 year was likewise affected with the same disorder. Moreover, the maternal grandmother had reportedly bald patches on her scalp and very dry skin. This is the first report to document linear skin lesions visualizing lyonization in women heterozygous for IFAP syndrome. A boy with congenital atrichia, ichthyosis follicular, keratitis, cutaneous infections and a huge inguinal hernia, but without deafness is reported. We believe it represents a new case of a rare X-linked recessive syndrome known as ichthyosis follicularis, alopecia, photophobia syndrome (IFAP). The differential diagnosis from keratitis ichthyosis deafness is discussed. The cutaneous infections seen in our case suggest the possibility of considering a genetic link between these syndromes. The IFAP syndrome is characterized by the congenital onset of ichthyosis follicularis, absence of hair, and photophobia. A limited number of patients with the disorder have been described, and X-linked recessive inheritance has been proposed. Two unrelated female patients with a complete IFAP syndrome are reported. Both patients show a diffuse distribution of the disorder without linear arrangement. Because the suggested X-linked recessive pattern of inheritance is unlikely in these patients, a different way of transmission or, alternatively, genetic heterogeneity of the disorder has to be considered. Two brothers with ichthyosis follicularis, noncicatricial universal alopecia, photophobia, hyerkeratotic psoriasis-like lesions, nails dystrophy, inguineal herniae, cryptorchidism, short stature, seizures, and psychomotor developmental delay are described. These features correspond to the ichthyosis follicularis, alopecia, photophobia (IFAP) syndrome. The youngest brother had in addition a bilateral absence of 4th fingers and camptodactyly, features never reported in patients with IFAP syndromes. PURPOSE: To report the ocular findings in two siblings with IFAP and their mother and to review the natural course of the keratopathy of this disease. METHODS: Clinical ophthalmological examination of all patients and fundus photography of the carrier mother were performed. RESULTS: Both affected male children had severe photophobia, total superficial and deep corneal vascularization, and reduction of vision to counting fingers.The mother had tortuous retinal vessels. CONCLUSIONS: Males with IFAP have an inexorable progression of corneal vascularization and loss of vision. Retinal vascular tortuosity may be another clinical sign of carrier status in females. We describe a 3-year-old male patient with the ichthyosis follicularis, alopecia and photophobia (IFAP) syndrome, who developed cutaneous and ocular involvement in infancy. In addition, he had growth retardation and borderline intelligence; no other systemic involvement was found on detailed investigation. A moderate response to acitretin therapy (1 mg/kg) administered for 6 months was observed, with improvement in cutaneous features and corneal erosions and no change in alopecia or photophobia. Ichthyosis follicularis, alopecia and photophobia (IFAP) is a rare genodermatosis. Most patients have been men without significant family history. We present the largest kindred of IFAP reported to date in the medical literature clearly demonstrating X-linked inheritance. The gene defect has recently been mapped to Xp22.11-p22.13. Missense mutations of the gene, MBTPS2, which codes for an intramembrane zinc metalloprotease essential for cholesterol homeostasis and endoplasmic reticulum stress response, are associated with the IFAP phenotype in this kindred. We describe the clinical features and discuss the differential diagnosis of IFAP. Our proband has benefited from treatment with acitretin. BACKGROUND: Ichthyosis follicularis, atrichia, and photophobia (IFAP) syndrome is a rare congenital disorder. Missense mutations in the membrane-bound transcription factor protease, site 2 (MBTPS2) gene have recently been identified in patients with IFAP. OBJECTIVE: To determine whether Chinese patients with IFAP have MBTPS2 mutations. METHODS: We observed a large IFAP pedigree of 5 generations in a Chinese family and performed MBTPS2 molecular analysis. RESULTS: The male proband was severely affected. He presented with hyperextensibility of the interphalangeal joints of the fingers in addition to previously reported clinical manifestations. Clinically affected female patients had hairless patches on the scalp, ichthyosiform skin changes, hypotrichosis, hyperkeratosis, nail dystrophy, and brown scaly plaques, some of which were arranged in a linear pattern following the lines of Blaschko. Molecular analysis identified a novel missense mutation in exon 11 and confirmed cosegregation of the missense mutation with the disease in this family. LIMITATIONS: It is unclear whether hyperextensibility of the fingers was nosologically related to IFAP syndrome or was a coincidental finding. CONCLUSION: This report provides further evidence for the genetic basis of IFAP syndrome and enlarges the phenotypic spectrum and number of MBTPS2 mutations. We confirm that MBTPS2 mutations cause IFAP in patients of Chinese origin. Mutations in MBTPS2 have been reported to cause a broad phenotypic spectrum of X-linked genodermatoses, including IFAP (ichthyosis follicularis; atrichia and photophobia) syndrome (OMIM 308205) with or without BRESHECK (brain anomalies, retardation of mentality and growth, ectodermal dysplasia, skeletal malformations, Hirschsprung disease, ear deformity and deafness, eye hypoplasia, cleft palate, cryptorchidism, and kidney dysplasia/hypoplasia) syndrome, keratosis follicularis spinulosa decalvans (KFSD; OMIM 308800) and an X-linked form of Olmsted syndrome. We report a recurrent intronic mutation in MBTPS2 (c.671-9T>G) in a Chinese patient with the typical triad of IFAP syndrome (i.e. ichthyosis, atrichia and photophobia), along with pachyonychia, palmoplantar and periorificial keratoderma, which were reminiscent of Olmsted syndrome. Interestingly, this mutation was previously reported in two cases of IFAP without keratoderma, which suggests clinical heterogeneicity of the same mutation in MBTPS2. The concomitance of Olmsted syndrome-like features in this patient with IFAP may challenge the existence of the X-linked form of Olmsted syndrome as an independent condition.
Which gene is required for the efficient function of clopidogrel?
The prodrug clopidogrel requires activation by cytochrome P-450 (CYP) enzymes for its antiplatelet effect. Variability in clopidogrel response might be influenced by polymorphisms in genes coding for drug metabolism enzymes (cytochrome P450 CYP2C19), transport proteins (P-glycoprotein) and/or target proteins for the drug (adenosine diphosphate-receptor P2Y12). The CYP2C19 loss-of-function alleles had a gene dose effect on the pharmacodynamics and composite ischemic events of clopidogrel in our study population. Neither the ABCB1 nor the PON1 genotype significantly influenced the antiplatelet effect and clinical outcomes of clopidogrel in these patients
BACKGROUND AND PURPOSE: There is considerable variability in the antiplatelet effects of the thienopyridine agent "clopidogrel." We tested for an association of gene sequence variations in P2Y12 and occurrence of neurological adverse events in patients with symptomatic peripheral artery disease (PAD) during clopidogrel treatment. METHODS: We studied 137 patients undergoing antiplatelet therapy with clopidogrel and 336 patients with aspirin for the occurrence of neurological events (ischemic stroke and/or carotid revascularization). Prevalence of 2 previously described exonic polymorphisms of the P2Y12 gene, 34C>T and 52G>T, was determined by polymerase chain reaction. RESULTS: Genotype frequencies for mutated, heterozygous, and wild-type alleles for the 34C>T and the 52G>T polymorphisms were 9% (n=40), 44% (n=210), and 47% (n=223), and 4% (n=17), 27% (n=127), and 70% (n=329), respectively. During the median follow-up of 21 months, neurological events occurred in 8% of patients. In patients with aspirin therapy, neither polymorphism was associated with neurological events. However, in clopidogrel patients, carriers of at least one 34T allele had a 4.02-fold increased adjusted risk for neurological events compared with carriers of only 34C alleles (95% confidence interval, 1.08 to 14.9). Neither polymorphism was associated with all-cause mortality. CONCLUSIONS: In PAD patients, clopidogrel response variability exists, which may result in increased risk for cerebrovascular events. Sequence alterations of the target receptor gene represent one possible mechanism for clopidogrel failure. Whether identification of the 34C>T polymorphism as a contributor to this process could serve as risk stratification tool, an indicator for higher clopidogrel doses, or the use of alternate agents warrants further investigation. OBJECTIVES: This study assessed the effect of pharmacogenetics on the antiplatelet effect of clopidogrel. BACKGROUND: Variability in clopidogrel response might be influenced by polymorphisms in genes coding for drug metabolism enzymes (cytochrome P450 [CYP] family), transport proteins (P-glycoprotein) and/or target proteins for the drug (adenosine diphosphate-receptor P2Y12). METHODS: Sixty patients undergoing elective percutaneous coronary intervention in the randomized PRINC (Plavix Response in Coronary Intervention) trial had platelet function measured using the VerifyNow P2Y12 analyzer after a 600-mg or split 1,200-mg loading dose and after a 75- or 150-mg daily maintece dosage. Polymerase chain reaction-based genotyping evaluated polymorphisms in the CYP2C19, CYP2C9, CYP3A4, CYP3A5, ABCB1, P2Y12, and CES genes. RESULTS: CYP2C19*1*1 carriers had greater platelet inhibition 2 h after a 600-mg dose (median: 23%, range: 0% to 66%), compared with platelet inhibition in CYP2C19*2 or *4 carriers (10%, 0% to 56%, p = 0.029) and CYP2C19*17 carriers (9%, 0% to 98%, p = 0.026). CYP2C19*2 or *4 carriers had greater platelet inhibition with the higher loading dose than with the lower dose at 4 h (37%, 8% to 87% vs. 14%, 0% to 22%, p = 0.002) and responded better with the higher maintece dose regimen (51%, 15% to 86% vs. 14%, 0% to 67%, p = 0.042). CONCLUSIONS: Carriers of the CYP2C19*2 and *4 alleles showed reduced platelet inhibition after a clopidogrel 600-mg loading dose but responded to higher loading and maintece dose regimens. Genotyping for the relevant gene polymorphisms may help to individualize and optimize clopidogrel treatment. (Australia New Zealand Clinical Trials Registry; ACTRN12606000129583). AIM: To determine the effect of various SNPs on post-clopidogrel platelet reactivity and clinical outcome. MATERIALS & METHODS: Cytochrome 2C19 (CYP2C19) loss-of-function (LOF; *2, *3) and gain-of-function (GOF; *17) allelic variants, together with ABCB1 (3435 C→T and 2677 G→T/A) and paraoxonase-1 (PON-1; 192 Q→R) SNPs were analyzed in 189 patients after elective stent implantation who participated in a randomized, placebo-controlled trial (NCT00638326). Platelet reactivity was determined with light transmission aggregometry and vasodilator stimulated phosphoprotein phosphorylation (VASP-PRI) 12-24 h after 600 mg clopidogrel. High on-treatment platelet reactivity (HTPR) was defined according to the consensus definition (ADP 5 µM >46%; VASP-PRI>50%). RESULTS: In the case of CYP2C19 genotypes, a gene-dose effect was observed in ADP reactivity with the lowest values in GOF homozygotes and the highest degree in patients carrying two LOF alleles. The odds for HTPR also increased with the number of LOF alleles. There were no significant differences in platelet reactivity according to PON-1 or ABCB1 genotypes. In multivariate analysis, the presence of a CYP2C19 LOF allele turned out to be the independent determit of HTPR. Although the study was not powered to clinical outcome (not LOF heterozygotes), only patients with two LOF alleles had a significantly higher risk for cardiovascular death, myocardial infarction or unplanned target vessel revascularization at 1 year compared with non-LOF carriers. CONCLUSION: Genetic variants in CYP2C19 have a gene-dose effect on post-clopidogrel platelet reactivity, with homozygote LOF carriers having the highest risk for HTPR and for adverse ischemic events. Neither ABCB1 nor PON-1 genotypes significantly influenced platelet reactivity or outcome. PURPOSE: Chinese people are more frequent carriers of cytochrome P450 2C19 (CYP2C19) loss-of-function alleles than Caucasians. The effect of the ATP-binding cassette, sub-family B, member 1 (ABCB1), and paraoxonase 1 (PON1) variants on platelet reactivity and clinical outcomes of clopidogrel treatment has not yet been reported in Chinese patients after percutaneous coronary intervention. The aim of this study was to investigate the effect of the CYP2C19, ABCB1, and PON1 variants on clopidogrel pharmacodynamics and clinical outcomes in these patients. METHODS: Six hundred and seventy patients after percutaneous coronary intervention were enrolled in a single-center registry. The antiplatelet effect of clopidogrel was assessed by thromboelastography, and the CYP2C19, ABCB1, and PON1 genotypes were detected by the ligase detection reaction. Primary clinical endpoints included cardiovascular death, nonfatal myocardial infarction, target vessel revascularization, and stent thrombosis. The secondary clinical endpoints were thrombolysis in myocardial infarction bleeding. The follow-up period was 12 months. RESULTS: The frequency of the CYP2C19 loss-of-function alleles was relatively high (57.3 %). The risk of a low response to clopidogrel and composite ischemic events increased with the number of CYP2C19 loss-of-function alleles. However, there were not significant differences in clopidogrel pharmacodynamics and clinical outcomes across the ABCB1 and PON1 genotype groups; bleeding was not significantly different across the CYP2C19, ABCB1, and PON1 genotype groups. CONCLUSIONS: The CYP2C19 loss-of-function alleles had a gene dose effect on the pharmacodynamics and composite ischemic events of clopidogrel in our study population. Neither the ABCB1 nor the PON1 genotype significantly influenced the antiplatelet effect and clinical outcomes of clopidogrel in these patients. BACKGROUND: The CYP2C19 G681A single polymorphism has been proven to affect clopidogrel responsiveness. However, the effect of coexisting polymorphisms of other genes has not yet been reported in the Chinese population. This study investigated the effect of coexisting polymorphisms of CYP2C19 and P2Y12 on clopidogrel responsiveness and adverse clinical events in Chinese patients. METHODS: In 577 Han Chinese patients undergoing stent placement because of acute coronary syndrome had platelet reactivity assessed by thromboelastography, and the CYP2C19 G681A and P2Y12 C34T polymorphisms were detected by the ligase detection reaction. Primary clinical endpoints included cardiovascular death, nonfatal myocardial infarction, target vessel revascularization, and stent thrombosis. The secondary clinical endpoints were thrombolysis in myocardial infarction bleeding. The follow-up period was 12 months. RESULTS: Genotyping revealed 194 carriers of the wild type GG genotype of CYP2C19 and the wild type CC genotype of P2Y12 (group 1), 102 carriers of the wild type GG genotype of CYP2C19 and the mutational T allele of P2Y12 (group 2), 163 carriers of the mutational A allele of CYP2C19 and the wild type CC genotype of P2Y12 (group 3), and 118 carriers of the mutational A allele of CYP2C19 and the mutational T allele of P2Y12 (group 4). Group 4 had the lowest ADP-inhibition (49.74 ± 32.61) and the highest prevalence of clopidogrel low response (29.7%) of the four groups. The rate of the composite of primary clinical endpoints increased more in group 4 (8.5%) than in the other three groups; the rate of composite primary endpoints in group 2 (2.9%) and group 3 (3.7%) were not significantly different than that of group 1 (1.5%). CONCLUSION: Coexisting polymorphisms of different genes affected clopidogrel responsiveness and clinical outcome more than single polymorphism in Chinese patients with acute coronary syndrome undergoing percutaneous coronary intervention.
Is valproic acid effective for glioblastoma treatment?
Yes, valproic acid prolong survival of glioblastoma patients. Valproic acid is an antiepileptic agent with histone deacetylase inhibitor activity shown to sensitize glioblastoma cells to radiation in preclinical models.
PURPOSE: Valproic acid (VA) is an antiepileptic drug (AED) and histone deacetylase (HDAC) inhibitor taken by patients with glioblastoma (GB) to manage seizures, and it can modulate the biologic effects of radiation therapy (RT). We investigated whether VA use during RT for GB was associated with overall survival (OS). METHODS AND MATERIALS: Medical records of 544 adults with GB were retrospectively reviewed. Analyses were performed to determine the association of Radiation Therapy Oncology Group recursive partitioning analysis (RTOG RPA) class, seizure history, and concurrent temozolomide (TMZ) and AED use during RT with OS. RESULTS: Seizures before the end of RT were noted in 217 (40%) patients, and 403 (74%) were taking an AED during RT; 29 (7%) were taking VA. Median OS in patients taking VA was 16.9 months (vs 13.6 months taking another AED, P=.16). Among patients taking an AED during RT, OS was associated with VA (P=.047; hazard ratio [HR], 0.67; 95% confidence interval [CI], 0.27-1.07), and RTOG RPA class (P<.0001; HR, 1.49; 95% CI, 1.37-1.61). Of the 5 most common AEDs, only VA was associated with OS. Median OS of patients receiving VA and TMZ during RT was 23.9 months (vs 15.2 months for patients taking another AED, P=.26). When the analysis was restricted to patients who received concurrent TMZ, VA use was marginally associated with OS (P=.057; HR, 0.54; 95% CI, -0.09 to 1.17), independently of RTOG RPA class and seizure history. CONCLUSIONS: VA use during RT for GB was associated with improved OS, independently of RTOG RPA, seizure history, and concurrent TMZ use. Further studies of treatment that combines HDAC inhibitors and RT are warranted. BACKGROUND: To examine the efficacy of valproic acid (VPA) given either with or without levetiracetam (LEV) on seizure control and on survival in patients with glioblastoma multiforme (GBM) treated with chemoradiation. METHODS: A retrospective analysis was performed on 291 patients with GBM. The efficacies of VPA and LEV alone and as polytherapy were analyzed in 181 (62%) patients with seizures with a minimum follow-up of 6 months. Cox-regression survival analysis was performed on 165 patients receiving chemoradiation with temozolomide of whom 108 receiving this in combination with VPA for at least 3 months. RESULTS: Monotherapy with either VPA or LEV was instituted in 137/143 (95.8%) and in 59/86 (68.6%) on VPA/LEV polytherapy as the next regimen. Initial freedom from seizure was achieved in 41/100 (41%) on VPA, in 16/37 (43.3%) on LEV, and in 89/116 (76.7%) on subsequent VPA/LEV polytherapy. At the end of follow-up, seizure freedom was achieved in 77.8% (28/36) on VPA alone, in 25/36 (69.5%) on LEV alone, and in 38/63 (60.3%) on VPA/LEV polytherapy with ongoing seizures on monotherapy. Patients using VPA in combination with temozolomide showed a longer median survival of 69 weeks (95% confidence interval [CI]: 61.7-67.3) compared with 61 weeks (95% CI: 52.5-69.5) in the group without VPA (hazard ratio, 0.63; 95% CI: 0.43-0.92; P = .016), adjusting for age, extent of resection, and O(6)-DNA methylguanine-methyltransferase promoter methylation status. CONCLUSIONS: Polytherapy with VPA and LEV more strongly contributes to seizure control than does either as monotherapy. Use of VPA together with chemoradiation with temozolomide results in a 2-months' longer survival of patients with GBM. PURPOSE: Glioblastoma multiforme (GBM) is the most lethal type of primary brain tumor, and patients that undergo the maximum tumor resection that is safely possible and standard radiochemotherapy only achieve a median survival time of 14.6 months. Several clinical studies have reported that valproic acid could prolong survival of GBM patients. However, the results of these studies are inconsistent. We examined relevant studies and conducted a meta-analysis to assess the effects of VPA on survival times and recurrence. METHODS: A bibliographic search was performed in the EMBASE, MEDLINE, ClinicalTrials.gov and Cochrane Central Register of the Controlled Trials databases to identify potentially relevant articles or conference abstracts that investigated the effects of VPA on the outcome of glioma patients. Five observational studies were included. RESULTS: Pooled estimates of the hazard ratio (HR) and 95% confidence intervals (CI) were calculated. Our meta-analysis confirmed the benefit of using VPA (HR, 0.56; 95% CI, 0.44-0.71). Sub-group analysis shows that patients treated with VPA had a hazard ratio of 0.74 with a 95% confidence interval of 0.59-0.94 vs. patients treated by other-AEDs and a hazard ratio of 0.66 with a 95% confidence interval of 0.52-0.84 vs. patients treated by administration of non-AEDs. No heterogeneity was observed in the subset analysis. CONCLUSION: The results of our study suggest that glioblastoma patients may experience prolonged survival due to VPA administration. Sub-analysis confirmed the benefit of VPA use compared to a non-AEDs group and an other-AEDs group. Further RCTs of this subject should be performed.
Which transcription factor is considered as a master regulator of lysosomal genes?
Transcription factor EB (TFEB) is a master regulator of lysosomal biogenesis and autophagy, driving lysosome adaptation to environmental cues, such as starvation, and therefore targeting of TFEB may provide a novel therapeutic strategy for modulating lysosomal function in human disease.
Mammalian target of rapamycin (mTOR) complex 1 (mTORC1) is an important, highly conserved, regulator of cell growth. Ancient among the signals that regulate mTORC1 are nutrients. Amino acids direct mTORC1 to the surface of the late endosome/lysosome, where mTORC1 becomes receptive to other inputs. However, the interplay between endosomes and mTORC1 is poorly understood. Here, we report the discovery of a network that links mTORC1 to a critical component of the late endosome/lysosome, the V-ATPase. In an unbiased screen, we found that mTORC1 regulated the expression of, among other lysosomal genes, the V-ATPases. mTORC1 regulates V-ATPase expression both in cells and in mice. V-ATPase regulation by mTORC1 involves a transcription factor translocated in renal cancer, TFEB. TFEB is required for the expression of a large subset of mTORC1 responsive genes. mTORC1 coordinately regulates TFEB phosphorylation and nuclear localization and in a manner dependent on both TFEB and V-ATPases, mTORC1 promotes endocytosis. These data uncover a regulatory network linking an oncogenic transcription factor that is a master regulator of lysosomal biogenesis, TFEB, to mTORC1 and endocytosis. The lysosome plays a key role in cellular homeostasis by controlling both cellular clearance and energy production to respond to environmental cues. However, the mechanisms mediating lysosomal adaptation are largely unknown. Here, we show that the Transcription Factor EB (TFEB), a master regulator of lysosomal biogenesis, colocalizes with master growth regulator mTOR complex 1 (mTORC1) on the lysosomal membrane. When nutrients are present, phosphorylation of TFEB by mTORC1 inhibits TFEB activity. Conversely, pharmacological inhibition of mTORC1, as well as starvation and lysosomal disruption, activates TFEB by promoting its nuclear translocation. In addition, the transcriptional response of lysosomal and autophagic genes to either lysosomal dysfunction or pharmacological inhibition of mTORC1 is suppressed in TFEB-/- cells. Interestingly, the Rag GTPase complex, which senses lysosomal amino acids and activates mTORC1, is both necessary and sufficient to regulate starvation- and stress-induced nuclear translocation of TFEB. These data indicate that the lysosome senses its content and regulates its own biogenesis by a lysosome-to-nucleus signalling mechanism that involves TFEB and mTOR. Loss-of-function diseases are often caused by destabilizing mutations that lead to protein misfolding and degradation. Modulating the innate protein homeostasis (proteostasis) capacity may lead to rescue of native folding of the mutated variants, thereby ameliorating the disease phenotype. In lysosomal storage disorders (LSDs), a number of highly prevalent alleles have missense mutations that do not impair the enzyme's catalytic activity but destabilize its native structure, resulting in the degradation of the misfolded protein. Enhancing the cellular folding capacity enables rescuing the native, biologically functional structure of these unstable mutated enzymes. However, proteostasis modulators specific for the lysosomal system are currently unknown. Here, we investigate the role of the transcription factor EB (TFEB), a master regulator of lysosomal biogenesis and function, in modulating lysosomal proteostasis in LSDs. We show that TFEB activation results in enhanced folding, trafficking and lysosomal activity of a severely destabilized glucocerebrosidase (GC) variant associated with the development of Gaucher disease (GD), the most common LSD. TFEB specifically induces the expression of GC and of key genes involved in folding and lysosomal trafficking, thereby enhancing both the pool of mutated enzyme and its processing through the secretory pathway. TFEB activation also rescues the activity of a β-hexosaminidase mutant associated with the development of another LSD, Tay-Sachs disease, thus suggesting general applicability of TFEB-mediated proteostasis modulation to rescue destabilizing mutations in LSDs. In summary, our findings identify TFEB as a specific regulator of lysosomal proteostasis and suggest that TFEB may be used as a therapeutic target to rescue enzyme homeostasis in LSDs. The mTORC1 complex supports cell growth and proliferation in response to energy levels, growth factors, and nutrients. The Rag guanosine triphosphatases (GTPases) activate mTORC1 in response to amino acids by promoting its redistribution to lysosomes. In this paper, we identify a novel role for Rags in controlling activation of transcription factor EB (TFEB), a master regulator of autophagic and lysosomal gene expression. Interaction of TFEB with active Rag heterodimers promoted recruitment of TFEB to lysosomes, leading to mTORC1-dependent phosphorylation and inhibition of TFEB. The interaction of TFEB with Rags required the first 30 residues of TFEB and the switch regions of the Rags G domain. Depletion or inactivation of Rags prevented recruitment of TFEB to lysosomes, whereas expression of active Rags induced association of TFEB with lysosomal membranes. Finally, Rag GTPases bound and regulated activation of microphthalmia-associated transcription factor, suggesting a broader role for Rags in the control of gene expression. Our work provides new insight into the molecular mechanisms that link nutrient availability and TFEB localization and activation. When the levels of intracellular amino acids are high, RRAG GTPases recruit MTORC1 to lysosomes and promote its activation. We found that RRAGs also recruit specific MTORC1 substrates to the lysosomal surface, thus facilitating MTORC1-mediated phosphorylation and regulation. In particular, active RRAGs interact with the transcription factor EB (TFEB), the master regulator of a gene network that promotes lysosomal biogenesis and autophagy. Redistribution to lysosomes is critical for MTORC1-dependent inactivation of TFEB under nutrient-rich conditions. Therefore, RRAGs play a critical role coordinating nutrient availability and cellular clearance. The lysosomal-autophagic pathway is activated by starvation and plays an important role in both cellular clearance and lipid catabolism. However, the transcriptional regulation of this pathway in response to metabolic cues is uncharacterized. Here we show that the transcription factor EB (TFEB), a master regulator of lysosomal biogenesis and autophagy, is induced by starvation through an autoregulatory feedback loop and exerts a global transcriptional control on lipid catabolism via Ppargc1α and Ppar1α. Thus, during starvation a transcriptional mechanism links the autophagic pathway to cellular energy metabolism. The conservation of this mechanism in Caenorhabditis elegans suggests a fundamental role for TFEB in the evolution of the adaptive response to food deprivation. Viral delivery of TFEB to the liver prevented weight gain and metabolic syndrome in both diet-induced and genetic mouse models of obesity, suggesting a new therapeutic strategy for disorders of lipid metabolism. For a long time, lysosomes were considered merely to be cellular 'incinerators' involved in the degradation and recycling of cellular waste. However, now there is compelling evidence indicating that lysosomes have a much broader function and that they are involved in fundamental processes such as secretion, plasma membrane repair, signalling and energy metabolism. Furthermore, the essential role of lysosomes in autophagic pathways puts these organelles at the crossroads of several cellular processes, with significant implications for health and disease. The identification of a master regulator, transcription factor EB (TFEB), that regulates lysosomal biogenesis and autophagy has revealed how the lysosome adapts to environmental cues, such as starvation, and targeting TFEB may provide a novel therapeutic strategy for modulating lysosomal function in human disease. OBJECTIVE: Recent reports of a proatherogenic phenotype in mice with macrophage-specific autophagy deficiency have renewed interest in the role of the autophagy-lysosomal system in atherosclerosis. Lysosomes have the unique ability to process both exogenous material, including lipids and autophagy-derived cargo such as dysfunctional proteins/organelles. We aimed to understand the effects of an atherogenic lipid environment on macrophage lysosomes and to evaluate novel ways to modulate this system. APPROACH AND RESULTS: Using a variety of complementary techniques, we show that oxidized low-density lipoproteins and cholesterol crystals, commonly encountered lipid species in atherosclerosis, lead to profound lysosomal dysfunction in cultured macrophages. Disruptions in lysosomal pH, proteolytic capacity, membrane integrity, and morphology are readily seen. Using flow cytometry, we find that macrophages isolated from atherosclerotic plaques also display features of lysosome dysfunction. We then investigated whether enhancing lysosomal function can be beneficial. Transcription factor EB (TFEB) is the only known transcription factor that is a master regulator of lysosomal biogenesis although its role in macrophages has not been studied. Lysosomal stress induced by chloroquine or atherogenic lipids leads to TFEB nuclear translocation and activation of lysosomal and autophagy genes. TFEB overexpression in macrophages further augments this prodegradative response and rescues several deleterious effects seen with atherogenic lipid loading as evidenced by blunted lysosomal dysfunction, reduced secretion of the proinflammatory cytokine interleukin-1β, enhanced cholesterol efflux, and decreased polyubiquitinated protein aggregation. CONCLUSIONS: Taken together, these data demonstrate that lysosomal function is markedly impaired in atherosclerosis and suggest that induction of a lysosomal biogenesis program in macrophages has antiatherogenic effects. Cerium oxide oparticles (oceria) are widely used in a variety of industrial applications including UV filters and catalysts. The expanding commercial scale production and use of ceria oparticles have inevitably increased the risk of release of oceria into the environment as well as the risk of human exposure. The use of oceria in biomedical applications is also being currently investigated because of its recently characterized antioxidative properties. In this study, we investigated the impact of ceria oparticles on the lysosome-autophagy system, the main catabolic pathway that is activated in mammalian cells upon internalization of exogenous material. We tested a battery of ceria oparticles functionalized with different types of biocompatible coatings (N-acetylglucosamine, polyethylene glycol and polyvinylpyrrolidone) expected to have minimal effect on lysosomal integrity and function. We found that ceria oparticles promote activation of the transcription factor EB, a master regulator of lysosomal function and autophagy, and induce upregulation of genes of the lysosome-autophagy system. We further show that the array of differently functionalized ceria oparticles tested in this study enhance autophagic clearance of proteolipid aggregates that accumulate as a result of inefficient function of the lysosome-autophagy system. This study provides a mechanistic understanding of the interaction of ceria oparticles with the lysosome-autophagy system and demonstrates that ceria oparticles are activators of autophagy and promote clearance of autophagic cargo. These results provide insights for the use of oceria in biomedical applications, including drug delivery. These findings will also inform the design of engineered oparticles with safe and precisely controlled impact on the environment and the design of otherapeutics for the treatment of diseases with defective autophagic function and accumulation of lysosomal storage material. Canonical Wnt signaling plays an important role in development and disease, regulating transcription of target genes and stabilizing many proteins phosphorylated by glycogen synthase kinase 3 (GSK3). We observed that the MiT family of transcription factors, which includes the melanoma oncogene MITF (micropthalmia-associated transcription factor) and the lysosomal master regulator TFEB, had the highest phylogenetic conservation of three consecutive putative GSK3 phosphorylation sites in animal proteomes. This finding prompted us to examine the relationship between MITF, endolysosomal biogenesis, and Wnt signaling. Here we report that MITF expression levels correlated with the expression of a large subset of lysosomal genes in melanoma cell lines. MITF expression in the tetracycline-inducible C32 melanoma model caused a marked increase in vesicular structures, and increased expression of late endosomal proteins, such as Rab7, LAMP1, and CD63. These late endosomes were not functional lysosomes as they were less active in proteolysis, yet were able to concentrate Axin1, phospho-LRP6, phospho-β-catenin, and GSK3 in the presence of Wnt ligands. This relocalization significantly enhanced Wnt signaling by increasing the number of multivesicular bodies into which the Wnt signalosome/destruction complex becomes localized upon Wnt signaling. We also show that the MITF protein was stabilized by Wnt signaling, through the novel C-terminal GSK3 phosphorylations identified here. MITF stabilization caused an increase in multivesicular body biosynthesis, which in turn increased Wnt signaling, generating a positive-feedback loop that may function during the proliferative stages of melanoma. The results underscore the importance of misregulated endolysosomal biogenesis in Wnt signaling and cancer. Lysosomes are ubiquitous membrane-enclosed organelles filled with an acidic interior and are central to the autophagic, endocytic, or phagocytic pathway. In contrast to its classical function as the waste management machinery, lysosomes are now considered to be an integral part of various cellular signaling processes. The diverse functionality of this single organelle requires a very complex and coordinated regulation of its activity with transcription factor EB (TFEB), a master regulator of lysosomal biogenesis, at its core. However, mechanisms by which TFEB is regulated are poorly understood. This study demonstrates that gemfibrozil, an agonist of peroxisome proliferator-activated receptor (PPAR) α, alone and in conjunction with all-trans-retinoic acid is capable of enhancing TFEB in brain cells. We also observed that PPARα, but not PPARβ and PPARγ, is involved in gemfibrozil-mediated up-regulation of TFEB. Reporter assay and chromatin immunoprecipitation studies confirmed the recruitment of retinoid X receptor α, PPARα, and PGC1α on the PPAR-binding site on the Tfeb promoter as well. Subsequently, the drug-mediated induction of TFEB caused an increase in lysosomal protein and the lysosomal abundance in cell. Collectively, this study reinforces the link between lysosomal biogenesis and lipid metabolism with TFEB at the crossroads. Furthermore, gemfibrozil may be of therapeutic value in the treatment of lysosomal storage disorders in which autophagy-lysosome pathway plays an important role.
Which antibiotics target peptidoglycan biosynthesis?
Under some conditions, both ramoplanin and vancomycin probes produce helicoid staining patterns along the cylindrical walls of B. subtilis cells. This work has implications for the design of ramoplanin derivatives and may influence how other proposed substrate binding antibiotics are studied. This was confirmed by in vitro studies involving a wall-membrane particulate fraction from Gaffkya homari in which peptidoglycan synthesis from UDP-MurNAc-tetrapeptide was inhibited by ramoplanin but not by vancomycin. New results support a two-state model for septal and peripheral PG synthesis at mid-cell, involvement of essential cell division proteins in PG remodeling, and mid-cell localization of proteins that organize PG biosynthesis and that form the protein translocation apparatus.
Mersacidin is an antibiotic peptide produced by Bacillus sp. strain HIL Y-85,54728 that belongs to the group of lantibiotics. Its activity in vivo against methicillin-resistant Staphylococcus aureus strains compares with that of the glycopeptide antibiotic vancomycin (S. Chatterjee, D. K. Chatterjee, R. H. Jani, J. Blumbach, B. N. Ganguli, N. Klesel, M. Limbert, and G. Seibert, J. Antibiot. 45:839-845, 1992). Incubation of Staphylococcus simulans 22 with mersacidin resulted in the cessation of growth and slow lysis. Biosyntheses of DNA, RNA, and protein were not affected, whereas incorporation of glucose and D-alanine was inhibited and a regular reduction in the level of cell wall thickness was observed. Thus, unlike type A lantibiotics, mersacidin does not form pores in the cytoplasmic membrane but rather inhibits cell wall biosynthesis. Comparison with tunicamycin-treated cells indicated that peptidoglycan rather than teichoic acid metabolism is primarily affected. Mersacidin caused the excretion of a putative cell wall precursor into the culture supernatant. The formation of polymeric peptidoglycan was effectively inhibited in an in vitro assay, probably on the level of transglycosylation. In contrast to vancomycin, the activity of mersacidin was not antagonized by the tripeptide diacetyl-L-Lys-D-Ala-D-Ala, indicating that on the molecular level its mode of action differs from those of glycopeptide antibiotics. These data together with electron microscopy suggest that mersacidin acts on a novel target, which opens new perspectives for the treatment of methicillin-resistant S. aureus. The lantibiotic mersacidin has been previously reported to interfere with bacterial peptidoglycan biosynthesis, [Brötz, H., Bierbaum, G., Markus, A., Molitor, E. & Sahl, H.-G. (1995) Antimicrob. Agents Chemother. 39, 714-719]. Here, we focus on the target reaction and describe a mersacidin-induced accumulation of UDP-N-acetylmuramoyl-pentapeptide, indicating that inhibition of peptidoglycan synthesis occurs after the formation of cytoplasmic precursors. In vitro studies involving a wall-membrane particulate fraction of Bacillus megaterium KM demonstrated that mersacidin did not prevent the synthesis of lipid II [undecaprenyl-diphosphoryl-N-acetylmuramoyl-(pentapeptide)-N-ac ety lglucosamine] but specifically the subsequent conversion of this intermediate into polymeric nascent glycan strands by transglycosylation. Comparison with other inhibitors of transglycosylation shows that the effective concentration of mersacidin in vitro is in the range of that of the glycopeptide antibiotic vancomycin but 2-3 orders of magnitude higher than that of the competitive enzyme inhibitor moenomycin. The analogy to the glycopeptides may hint at an interaction of mersacidin with the peptidoglycan precursor rather than with the enzyme. Unlike vancomycin however, mersacidin inhibits peptidoglycan formation from UDP-N-acetylmuramoyl-tripeptide and is active against Enterococcus faecium expressing the vanA resistance gene cluster. This indicates that the molecular target site of mersacidin differs from that of vancomycin and that no cross-resistance exists between the two antibiotics. Vancomycin binds to bacterial cell-wall intermediates to achieve its antibiotic effect. Infections of vancomycin-resistant enterococci are, however, becoming an increasing problem; the bacteria are resistant because they synthesize different cell-wall intermediates. The enzymes involved in cell-wall biosynthesis, therefore, are potential targets for combating this resistance. Recent biochemical and crystallographic results are providing mechanistic and structural details about some of these targets. Mycobacterium smegmatis is a fast-growing nonpathogenic species particularly useful in studying basic cellular processes of relevance to pathogenic mycobacteria. This study focused on the D-alanine racemase gene (alrA), which is involved in the synthesis of D-alanine, a basic component of peptidoglycan that forms the backbone of the cell wall. M. smegmatis alrA null mutants were generated by homologous recombination using a kanamycin resistance marker for insertional inactivation. Mutants were selected on Middlebrook medium supplemented with 50 mM D-alanine and 20 microg of kanamycin per ml. These mutants were also able to grow in standard and minimal media without D-alanine, giving rise to colonies with a drier appearance and more-raised borders than the wild-type strain. The viability of the mutants and independence of D-alanine for growth indicate that inactivation of alrA does not impose an auxotrophic requirement for D-alanine, suggesting the existence of a new pathway of D-alanine biosynthesis in M. smegmatis. Biochemical analysis demonstrated the absence of any detectable D-alanine racemase activity in the mutant strains. In addition, the alrA mutants displayed hypersusceptibility to the antimycobacterial agent D-cycloserine. The MIC of D-cycloserine for the mutant strain was 2.56 microg/ml, 30-fold less than that for the wild-type strain. Furthermore, this hypersusceptibility was confirmed by the bactericidal action of D-cycloserine on broth cultures. The kinetic of killing for the mutant strain followed the same pattern as that for the wild-type strain, but at a 30-fold-lower drug concentration. This effect does not involve a change in the permeability of the cell wall by this drug and is consistent with the identification of D-alanine racemase as a target of D-cycloserine. This outcome is of importance for the design of novel antituberculosis drugs targeting peptidoglycan biosynthesis in mycobacteria. The muraymycins, a family of nucleoside-lipopeptide antibiotics, were purified from the extract of Streptomyces sp. LL-AA896. The antibiotics were purified by chromatographic methods and characterized by NMR spectroscopy, degradation studies, and mass spectrometry. The structures of 19 compounds were established. The muraymycins constitute a new antibiotic family whose core structure contains a glycosylated uronic acid derivative joined by an aminopropane group to a hexahydro-2-imino-4-pyrimidylglycyl residue (epicapreomycidine) containing dipeptide that is further extended by a urea-valine moiety. Members of this family show broad-spectrum in vitro antimicrobial activity against a variety of clinical isolates (MIC 2 to >64 mug/mL). The muraymycins inhibited peptidoglycan biosynthesis. The fatty acid substituent and the presence or absence of the amino sugar play important roles in biological activity. One of the most active compounds, muraymycin A1, demonstrated protection in vivo against Staphylococcus aureus infection in mice (ED50 1.1 mg/kg). The peptidoglycan (PG) layers surrounding bacterial cells play an important role in determining cell shape. The machinery controlling when and where new PG is made is not understood, but is proposed to involve interactions between bacterial actin homologs such as Mbl, which forms helical cables within cells, and extracellular multiprotein complexes that include penicillin-binding proteins. It has been suggested that labeled antibiotics that bind to PG precursors may be useful for imaging PG to help determine the genes that control the biosynthesis of this polymer. Here, we compare the staining patterns observed in Bacillus subtilis using fluorescent derivatives of two PG-binding antibiotics, vancomycin and ramoplanin. The staining patterns for both probes exhibit a strong dependence on probe concentration, suggesting antibiotic-induced perturbations in PG synthesis. Ramoplanin probes may be better imaging agents than vancomycin probes because they yield clear staining patterns at concentrations well below their minimum inhibitory concentrations. Under some conditions, both ramoplanin and vancomycin probes produce helicoid staining patterns along the cylindrical walls of B. subtilis cells. This sidewall staining is observed in the absence of the cytoskeletal protein Mbl. Although Mbl plays an important role in cell shape determination, our data indicate that other proteins control the spatial localization of the biosynthetic complexes responsible for new PG synthesis along the walls of B. subtilis cells. Specific drug-sensing systems that coordinate appropriate genetic responses assure the survival of microorganisms in the presence of antibiotics. We report on the development and application of a microtiter plate-based bioassay for the identification of antibiotics interfering with the lipid II cycle essential for peptidoglycan biosynthesis. A Bacillus subtilis reporter strain sensing specifically lipid II - interfering cell wall biosynthesis stress (T. Mascher, S.L. Zimmer, T.-A. Smith and J. Helmann, Antibiotic-inducible promoter regulated by the cell envelope stress-sensing two-component system LiaRS of Bacillus subtilis; Antimicrob. Agents Chemother., Vol 48 (2004) pp. 2888-2896) was analyzed in the presence of different lantibiotics. We could show dose-dependent cell wall biosynthesis stress of reporter cells in response to the action of the lantibiotics subtilin produced by B. subtilis, epidermin and gallidermin of Staphylococcus epidermidis or S. gallinarum, respectively, in both, agar-plate and liquid culture-based assays. Surprisingly, also cinnamycin of Streptomyces cinnamoneus cinnamoneus), previously known to bind specifically to phosphatidylethanolamin of biological membranes, provoked strong cell wall biosynthetic stress. Our results show that our system can be used for screening purposes, for example to discover novel inhibitors of cell wall biosynthesis. BACKGROUND: Staphylococcus aureus is a highly adaptable human pathogen and there is a constant search for effective antibiotics. Fosfomycin is a potent irreversible inhibitor of MurA, an enolpyruvyl transferase that uses phosphoenolpyruvate as substrate. The goal of this study was to identify the pathways and processes primarily affected by fosfomycin at the genome-wide transcriptome level to aid development of new drugs. RESULTS: S. aureus ATCC 29213 cells were treated with sub-MIC concentrations of fosfomycin and harvested at 10, 20 and 40 minutes after treatment. S. aureus GeneChip statistical data analysis was complemented by gene set enrichment analysis. A visualization tool for mapping gene expression data into biological pathways was developed in order to identify the metabolic processes affected by fosfomycin. We have shown that the number of significantly differentially expressed genes in treated cultures increased with time and with increasing fosfomycin concentration. The target pathway - peptidoglycan biosynthesis - was upregulated following fosfomycin treatment. Modulation of transport processes, cofactor biosynthesis, energy metabolism and nucleic acid biosynthesis was also observed. CONCLUSIONS: Several pathways and genes downregulated by fosfomycin have been identified, in contrast to previously described cell wall active antibiotics, and was explained by starvation response induced by phosphoenolpyruvate accumulation. Transcriptomic profiling, in combination with meta-analysis, has been shown to be a valuable tool in determining bacterial response to a specific antibiotic. Charophytes is a green algal group closely related to land plants. We investigated the effects of antibiotics that interfere with peptidoglycan biosynthesis on chloroplast division in the desmid Closterium peracerosum-strigosum-littorale complex. To detect cells just after division, we used colchicine, which inhibits Closterium cell elongation after division. Although normal Closterium cells had two chloroplasts before and after cell division, cells treated with ampicillin, D-cycloserine, or fosfomycin had only one chloroplast after cell division, suggesting that the cells divided without chloroplast division. The antibiotics bacitracin and vancomycin showed no obvious effect. Electron microscopic observation showed that irregular-shaped chloroplasts existed in ampicillin-treated Closterium cells. Because antibiotic treatments resulted in the appearance of long cells with irregular chloroplasts and cell death, we counted cell types in the culture. The results suggested that cells with one chloroplast appeared first and then a huge chloroplast was generated that inhibited cell division, causing elongation followed by cell death. In this study, global intra- and extracellular metabolic profiles were exploited to investigate the impact of antibiotic compounds with different cellular targets on the metabolome of Staphylococcus aureus HG001. Primary metabolism was largely covered, yet uncommon staphylococcal metabolites were detected in the cytosol of S. aureus, including sedoheptulose-1,7-bisphosphate and the UDP-MurNAc-pentapeptide with an alanine-seryl residue. By comparing the metabolic profiles of unstressed and stressed staphylococcal cells in a time-dependent manner, we found far-ranging effects within the metabolome. For each antibiotic compound, accumulation as well as depletion of metabolites was detected, often comprising whole biosynthetic pathways, such as central carbon and amino acid metabolism and peptidoglycan, purine, and pyrimidine synthesis. Ciprofloxacin altered the pool of (deoxy)nucleotides as well as peptidoglycan precursors, thus linking stalled DNA and cell wall synthesis. Erythromycin tended to increase the amounts of intermediates of the pentose phosphate pathway and lysine. Fosfomycin inhibited the first enzymatic step of peptidoglycan synthesis, which was followed by decreased levels of peptidoglycan precursors but enhanced levels of substrates such as UDP-GlcNAc and alanine-alanine. In contrast, vancomycin and ampicillin inhibited the last stage of peptidoglycan construction on the outer cell surface. As a result, the amounts of UDP-MurNAc-peptides drastically increased, resulting in morphological alterations in the septal region and in an overall decrease in central metabolite levels. Moreover, each antibiotic affected intracellular levels of tricarboxylic acid cycle intermediates.
Can Levoxyl (levothyroxine sodium) cause insomnia?
Levoxyl monotherapy is associated with increased insomnia compared to a combination of levothyroxine and liothyronine.
OBJECTIVES: To examine the efficacy of combination therapy with levothyroxine and liothyronine in improvement of general health, psychological problems, and metabolic status in primary hypothyroidism. METHODS: Seventy-one patients diagnosed with primary hypothyroidism were randomly allocated into two study groups: the first group received usual dose of levothyroxine and the second group received combination of levothyroxine and liothyronine for at least 4 months. The main outcomes were psychosocial problems (Goldberg's General Health Questionnaire, GHQ-28), bodyweight, heart rate, blood pressure, and serum lipid levels. RESULTS: In both groups serum thyroid-stimulating hormone levels remained unchanged compared with baseline. Psychosocial scores, body weight, heart rate, blood pressure, and lipid profile in the two groups remained constant. The only exception was a small but significant reduction in anxiety/insomnia in combined treatment group as compared with monotherapy. CONCLUSIONS: The data do not support the hypothesis that combined therapy improves the well-being and general health of patients.
Is fatigue prevalent in patients receiving treatment for glioblastoma?
Yes, fatigue is a common complication of glioblastoma patients receiving chemotherapy or radiotherapy.
In the 1950's it was first observed that mammalian cells exposed to the halogenated deoxyuridines were more sensitive to ultraviolet light and radiation than untreated cells. This prompted early clinical trials with bromodeoxyuridine (BUdR) which showed mixed results. More recently, several Phase I studies, while establishing the feasibility of continuous intravenous (IV) infusion of BUdR, have reported significant dose limiting skin and bone marrow toxicities and have questioned the optimal method of BUdR delivery. To exploit the high mitotic activity of maligt gliomas relative to surrounding normal brain tissue, we have developed a permanently implantable infusion pump system for safe, continuous intraarterial (IA) internal carotid BUdR delivery. Since July 1985, 23 patients with maligt brain tumors (18 grade 4, 5 grade 3) have been treated in a Phase I clinical trial using IA BUdR (400-600 mg/m2/day X 8 1/2 weeks) and focal external beam radiotherapy (59.4 Gy at 1.8 Gy/day in 6 1/2 weeks). Following initial biopsy/surgery the infusion pump system was implanted; BUdR infusion began 2 weeks prior to and continued throughout the 6 1/2 week course of radiotherapy. There have been no vascular complications. Side-effects in all patients have included varying degrees of anorexia, fatigue, ipsilateral forehead dermatitis, blepharitis, and conjunctivitis. Myelosuppression requiring dose reduction occurred in one patient. An overall Kaplan-Meier estimated median survival of 20 months has been achieved. As in larger controlled series, histologic grade and age are prognostically significant. We have shown in a Phase I study that IA BUdR radiosensitization is safe, tolerable, may lead to improved survival, and appears to be an efficacious primary treatment of maligt gliomas. OBJECTIVES: The optimal treatment for elderly patients (age >70 years) with glioblastoma (GBM) remains controversial. We conducted a prospective trial in 43 consecutive elderly patients with GBM treated with hypofractionated radiotherapy (RT) followed by adjuvant temozolomide. PATIENTS AND METHODS: Forty-three patients 70 years of age or older with a newly diagnosed GBM and a Karnofsky performance status (KPS) > or = 60 were treated with hypofractionated RT (6 fractions of 5 Gy each for a total of 30 Gy over 2 weeks) followed by up to 12 cycles of adjuvant temozolomide (150-200 mg/m(2) for 5 days during each 28 day cycle). The HRQOL was assessed with the EORTC Quality of Life Questionnaire C30. The primary endpoint was overall survival (OS). Secondary endpoints included progression free survival (PFS), toxicity and quality of life. RESULTS: The median OS was 9.3 months and the median PFS was 6.3 months. The 6 and 12 month survival rates were 86% and 35%, respectively. The 6 and 12 month PFS rates were 55% and 12%, respectively. In multivariate analysis KPS was the only significant independent predictive factor of survival (P = 0.008). Neurological deterioration occurred during or after RT in 16% of patients and was resolved in most cases with the use of steroids. Grade 3-4 hematologic toxicity occurred in 28% of patients during the adjuvant chemotherapy treatment with temozolomide. The treatment had no negative effect on HRQOL, however, fatigue (P = 0.02) and constipation (P = 0.01) scales worsened over time. CONCLUSIONS: Hypofractionated RT followed by temozolomide may provide survival benefit maintaining a good quality of life in elderly patients with GBM. It may represent a reasonable therapeutic approach especially in patients with less favourably prognostic factors. A retrospective evaluation of single agent bevacizumab in adults with recurrent glioblastoma (GBM) with an objective of determining progression free survival (PFS). There is no standard therapy for recurrent GBM after failure of alkylator-based chemotherapy. A total of 50 adults, ages 36-70 years (median 64), with recurrent GBM were treated. All patients had previously been treated with surgery, concurrent radiotherapy and temozolomide, post-radiotherapy temozolomide and in 34 patients, one salvage regimen (PCV: 21, cyclophosphamide: 13). A total of 13 patients underwent repeat surgery. Patients were treated at first or second recurrence with bevacizumab, once every 2 weeks, defined as a single cycle. Neurological evaluation was performed every 2 weeks and neuroradiographic assessment following the initial 2 cycles of bevacizumab and subsequently after every 4 cycles of bevacizumab. A total of 468 cycles of bevacizumab (median 2 cycles; range 1-30) was administered. Bevacizumab-related toxicity included fatigue (16 patients; 4 grade 3), leukopenia (9; 1 grade 3), anemia (5; 0 grade 3), hypertension (7; 1 grade 3), deep vein thrombosis (4; 1 grade 3) and wound dehiscence (2; 1 grade 3). 21 patients (42%) demonstrated a partial radiographic response and 29 (58%) progressive disease following 1-2 cycles of bevacizumab. Time to tumor progression ranged from 0.5 to 15 months (median: 1.0 months). Survival ranged from 2 to 17 months (median: 8.5 months). 6-month and 12-month PFS were 42% and 22% respectively. Single agent bevacizumab demonstrated efficacy and acceptable toxicity in this cohort of adults with recurrent alkylator-refractory GBM. The objective of this phase II single-arm study was to evaluate the efficacy and safety of pazopanib, a multi-targeted tyrosine kinase inhibitor, against vascular endothelial growth factor receptor (VEGFR)-1, -2, and -3, platelet-derived growth factor receptor-alpha and -beta, and c-Kit, in recurrent glioblastoma. Patients with < or =2 relapses and no prior anti-VEGF/VEGFR therapy were treated with pazopanib 800 mg daily on 4-week cycles without planned interruptions. Brain magnetic resoce imaging and clinical reassessment were made every 8 weeks. The primary endpoint was efficacy as measured by 6-month progression-free survival (PFS6). Thirty-five GBM patients with a median age of 53 years and median Karnofsky performance scale of 90 were accrued. Grade 3/4 toxicities included leukopenia (n = 1), lymphopenia (n = 2), thrombocytopenia (n = 1), ALT elevation (n = 3), AST elevation (n = 1), CNS hemorrhage (n = 1), fatigue (n = 1), and thrombotic/embolic events (n = 3); 8 patients required dose reduction. Two patients had a partial radiographic response by standard bidimensional measurements, whereas 9 patients (6 at the 8-week point and 3 only within the first month of treatment) had decreased contrast enhancement, vasogenic edema, and mass effect but <50% reduction in tumor. The median PFS was 12 weeks (95% confidence interval [CI]: 8-14 weeks) and only 1 patient had a PFS time > or =6 months (PFS6 = 3%). Thirty patients (86%) had died and median survival was 35 weeks (95% CI: 24-47 weeks). Pazopanib was reasonably well tolerated with a spectrum of toxicities similar to other anti-VEGF/VEGFR agents. Single-agent pazopanib did not prolong PFS in this patient population but showed in situ biological activity as demonstrated by radiographic responses. ClinicalTrials.gov identifier: NCT00459381. PURPOSE: Amplification of the epidermal growth factor receptor (EGFR) gene represents one of the most frequent gene alterations in glioblastoma (GBM). In the current study, we evaluated gefitinib, a potent EGFR inhibitor, in the treatment of adults with newly diagnosed GBM. METHODS AND MATERIALS: Ninety-eight patients (96 evaluable) were accrued between May 18, 2001, and August 2, 2002. All were newly diagnosed GBM patients who were clinically and radiographically stable/improved after radiation treatment (enrollment within 5 weeks of radiation completion). No prior chemotherapy was permitted. EGFR amplification/mutation, as assessed by fluorescence in situ hybridization and immunohistochemistry, was not required for treatment with gefitinib but was studied when tissues were available. Gefitinib was administered at 500 mg each day; for patients receiving dexamethasone or enzyme-inducing (CYP3A4) agents, dose was escalated to a maximum of 1,000 mg QD. Treatment cycles were repeated at 4-week intervals with brain magnetic resoce imaging at 8-week intervals. RESULTS: Overall survival (OS; calculated from time of initial surgery) at 1 year (primary end point) with gefitinib was 54.2%, which was not statistically different compared with that of historical control population (48.9%, data from three previous Phase III North Central Cancer Treatment Group studies of newly diagnosed GBM patients). Progression-free survival (PFS) at 1 year post-RT (16.7%) was also not significantly different to that of historical controls (30.3%). Clinical outcome was not affected by EGFR status (amplification or vIII mutation). Fatigue (41%), rash (62%), and loose stools (58%) constituted the most frequent adverse events, the majority of these being limited to Grade 1/2. Of note, the occurrence of drug-related adverse effects, such as loose stools was associated with improved OS. CONCLUSIONS: In our evaluation of nearly 100 patients with newly diagnosed GBM, treatment with adjuvant gefitinib post-radiation was not associated with significant improvement in OS or PFS. However, patients who experienced gefitinib-associated adverse effects (rash/diarrhea) did demonstrate improved OS. BACKGROUND: The authors evaluated a 3-week schedule of bevacizumab in patients with recurrent high-grade glioma (HGG). METHODS: Patients received bevacizumab 15 mg/kg every 3 weeks and were evaluated every 6 weeks until tumor progression. Tissue correlates were used to quantify tumor content of vascular endothelial growth factor A (VEGFA) and vascular endothelial growth factor receptor-2 (VEGFR2). RESULTS: Of 61 patients who were treated (35 men and 26 women; median age, 52 years; age range, 21-78 years), 50 patients had glioblastoma multiforme (GBM), and 11 patients had anaplastic glioma (AG). The median number of previous chemotherapies was 2 (range, 1-5 previous chemotherapies), and 16 patients had received ≥3 previous chemotherapies. The median number of bevacizumab doses was 4 (range, 1-20 doses), and 45% of patients received >5 doses. The toxicities observed were primarily grade 1 and 2, and the most common were fatigue, hypertension, and headache. One grade 2 intratumoral bleed and 1 bowel perforation were reported. For patients with GBM, the 6-month progression-free survival rate was 25%, the median time to tumor progression was 10.8 weeks, and the median overall survival was 25.6 weeks. The best response included a partial response in 15 patients (24.5%) and stable disease in 31 patients (50.8%) patients; radiographic recurrence patterns included increased changes in fluid attenuation inversion recovery (24%) and multifocal recurrence (20%). The median survival after bevacizumab failure was 10 weeks. The ratio of tumor VEGFA/VEGFR2 was increased in patients aged >55 years; an increased VEGFA/VEGFR2 ratio was correlated nonsignificantly with decreased survival (P = .052). CONCLUSIONS: An every-3-week schedule of bevacizumab had antitumor activity and was relatively nontoxic for patients with recurrent HGG. The predictive value of VEGFA/VEGFR2 in tumor will require validation in a larger patient cohort. External beam radiation therapy (XRT) with concomitant temozolomide and 6 cycles of adjuvant temozolomide (5/28-day schedule) improves survival in patients with newly diagnosed glioblastoma compared with XRT alone. Studies suggest that dose-dense temozolomide schedules and addition of cytostatic agents may further improve efficacy. This factorial design phase I/II protocol tested dose-dense temozolomide alone and combined with cytostatic agents. Patients with newly diagnosed glioblastoma received fractionated XRT to 60 Gy concomitant with temozolomide (75 mg/m²)/day for 42 days). In the phase I portion, patients with stable disease or radiologic response 1 month after chemoradiation were randomized to adjuvant temozolomide alone (150 mg/m²/day, 7/14-day schedule) or with doublet combinations of thalidomide (400 mg/day), isotretinoin (100 mg/m²/day), and/or celecoxib (400 mg twice daily), or all 3 agents. Toxicity was assessed after 4 weeks. Among 54 patients enrolled (median age, 52 years; median Karnofsky performance status, 90), adjuvant treatment was not administered to 12 (22%), primarily because of disease progression (n = 10). All combinations were well tolerated. Grade 3/4 lymphopenia developed in 63% of patients, but no related infections occurred. One patient treated with temozolomide plus isotretinoin plus thalidomide had dose-limiting grade 3 fatigue and rash, and 1 patient receiving all 4 agents had dose-limiting grade 4 neutropenia. Venous thrombosis occurred in 7 patients, 4 of whom received thalidomide. From study entry, median survival was 20 months and the 2-year survival rate was 40%. Multiple cytostatic agents can be safely combined with dose-dense temozolomide. The factorial-based phase II portion of this study is currently ongoing. OBJECTIVE: The combination of irinotecan-bevacizumab is effective in patients with glioblastoma relapse but fatigue is a commonly reported side effect. The objective of this study was to evaluate the level and evolution of fatigue in a series of patients treated with therapeutic combination. PATIENTS AND METHODS: We used two self-evaluation tools to quantify the physical and emotional aspects of this fatigue. The Norris Visual Analog Scale (VAS Norris) and the Multidimensional Fatigue Inventory-20 (MFI) tools were undertaken by 39 patients with glioblastoma relapse treated with irinotecan-bevacizumab, initially before the first cycle and thereafter with each cycle up until tumor progression. RESULTS: Analysis of the results of the VAS Norris scale did not demonstrate an increase in emotional fatigue but did show an increase in physical fatigue that did not reach statistical significance. With regards to the MFI 20 tool, analysis of the results demonstrated a significant increase in general (P=0.0260) as well as physical (P=0.0141) fatigue but there was no difference in the other indices. CONCLUSION: This study demonstrated a progressive increase in physical fatigue in patients with glioblastoma relapse treated with irinotecan-bevacizumab. We suspect that this is as a direct consequence of the treatment. There are however other confounding factors: insidious tumour progression not detected on follow-up imaging or delayed side effects of the initial radiotherapy-chemotherapy. PURPOSE: Radiotherapy (RT) and chemotherapy may prolong survival in older patients (age ≥70 years) with glioblastoma multiforme (GBM), although the survival benefits remain poor. This Phase II multicenter study was designed to evaluate the efficacy and safety of an abbreviated course of RT plus concomitant and adjuvant temozolomide (TMZ) in older patients with GBM. PATIENTS AND METHODS: Seventy-one eligible patients 70 years of age or older with newly diagnosed GBM and a Karnofsky performance status ≥60 were treated with a short course of RT (40 Gy in 15 fractions over 3 weeks) plus TMZ at the dosage of 75 mg/m(2) per day followed by 12 cycles of adjuvant TMZ (150-200 mg/m(2) for 5 days during each 28-day cycle). The primary endpoint was overall survival (OS). Secondary endpoints included progression-free survival and toxicity. RESULTS: The Median OS was 12.4 months, and the 1-year and 2-year OS rates were 58% and 20%, respectively. The median and 1-year rates of progression-free survival were 6 months and 20%, respectively. All patients completed the planned programme of RT. Grade 3 or 4 adverse events occurred in 16 patients (22%). Grade 3 and 4 neutropenia and/or thrombocytopenia occurred in 10 patients (15%), leading to the interruption of treatment in 6 patients (8%). Nonhematologic Grade 3 toxicity was rare, and included fatigue in 4 patients and cognitive disability in 1 patient. CONCLUSIONS: A combination of an abbreviated course of RT plus concomitant and adjuvant TMZ is well tolerated and may prolong survival in elderly patients with GBM. Future randomized studies need to evaluate the efficacy and toxicity of different schedules of RT in association with chemotherapy. Vorinostat, a histone deacetylase (HDAC) inhibitor, has shown evidence of single-agent activity in glioblastoma (GBM), and in preclinical studies, we have demonstrated significant synergistic cytotoxicity between HDAC inhibitors and proteasome inhibitors in GBM cell lines. We therefore conducted a phase II trial to evaluate the efficacy of vorinostat in combination with the proteasome inhibitor bortezomib in patients with recurrent GBM. Vorinostat was administered at a dose of 400 mg daily for 14 days of a 21-day cycle, and bortezomib was administered at a dose of 1.3 mg/m(2) intravenously on days 1, 4, 8, and 11 of the cycle. A total of 37 patients were treated, and treatment was well tolerated: grade 3, 4 nonhematologic toxicity occurred in 30% of patients and consisted mainly of fatigue (14%) and neuropathy (5%); grade 3, 4 hematologic toxicity occurred in 37% of patients and consisted of thrombocytopenia (30%), lymphopenia (4%), and neutropenia (4%). The trial was closed at the predetermined interim analysis, with 0 of 34 patients being progression-free at 6 months. One patient achieved a partial response according to the Macdonald criteria. The median time to progression for all patients was 1.5 months (range, 0.5-5.6 months), and median overall survival (OS) was 3.2 months. Patients who had received prior bevacizumab therapy had a shorter time to progression and OS, compared with those who had not. On the basis of the results of this phase II study, further evaluation of the vorinostat-bortezomib combination in GBM patients in this dose and schedule is not recommended. Single-agent sunitinib, an oral small molecule inhibitor of multiple tyrosine kinase receptors, was evaluated for treatment of patients with recurrent glioblastoma (GB) and anaplastic astrocytoma (AA). Fourteen AA and 16 GB patients, all previously treated with surgery, radiotherapy, and temozolomide, were enrolled in a prospective phase II study at either first or second relapse. Patients were treated with daily sunitinib for 4 consecutive weeks, followed by a 2-week break. For AA patients, the most common side effects were fatigue (86 %), diarrhea (43 %), hand-foot syndrome (36 %), neutropenia (36 %), thrombocytopenia (36 %), and nausea (29 %). In the GB cohort, the most common side effects were fatigue (56 %), diarrhea (44 %), neutropenia (31 %), and thrombocytopenia (25 %). Six of 14 (43 %) AA and 5 of 16 (31 %) GB patients experienced grade 3 or greater toxicities. Five patients discontinued study due to drug toxicities. There were no partial or complete responses in either cohort; 8/14 (57 %) AA and 5/16 (31 %) GB patients had stable disease at the first planned assessment. Progression-free survival at 6 months was 21.5 % (AA) and 16.7 % (GB). Median overall survival was 12.1 months (AA) and 12.6 months (GB). These results are comparable to those reported in the literature in patients treated with standard cytotoxic therapies. This is the largest reported trial of sunitinib in recurrent maligt astrocytic gliomas to date, as well as contains the largest AA cohort. Nonetheless, sunitinib did not demonstrate significant anti-glioma activity in patients with recurrent maligt astrocytic gliomas. The Radiation Therapy Oncology Group (RTOG) initiated the single-arm, phase II study 9806 to determine the safety and efficacy of daily thalidomide with radiation therapy in patients with newly diagnosed glioblastoma. Patients were treated with thalidomide (200 mg daily) from day one of radiation therapy, increasing by 100-200 to 1,200 mg every 1-2 weeks until tumor progression or unacceptable toxicity. The median survival time (MST) of all 89 evaluable patients was 10 months. When compared with the historical database stratified by recursive partitioning analysis (RPA) class, this end point was not different [hazard ratio (HR) = 1.18; 95 % CI: 0.95-1.46; P = 0.93]. The MST of RPA class III and IV patients was 13.9 versus 12.5 months in controls (HR = 0.99; 95 % CI: 0.73-1.36; P = 0.48), and 4.3 versus 8.6 months in RPA class V controls (HR = 1.63, 95 % CI: 1.17-2.27; P = 0.99). In all, 34 % of patients discontinued thalidomide because of adverse events or refusal. The most common grade 3-4 toxicities were venous thrombosis, fatigue, skin reactions, encephalopathy, and neuropathy. In conclusion, thalidomide given simultaneously with radiation therapy was safe, but did not improve survival in patients with newly diagnosed glioblastoma. BACKGROUND: Bevacizumab, a humanized recombit anti-vascular endothelial growth factor antibody, was approved in Canada in 2010 for the treatment of high-grade glioma. We report the effectiveness and safety of bevacizumab in the treatment of patients with recurrent high-grade gliomas at a single institution. METHODS: Twenty-seven consecutive patients with high-grade glioma (anaplastic glioma and glioblastoma) at first or subsequent relapse were treated with bevacizumab alone or in combination with chemotherapy. The primary endpoint was progression-free survival (PFS) and secondary endpoints were objective response rate, six month PFS, overall survival (OS), and safety profile. RESULTS: The clinical benefit rate (complete and partial responses plus stable disease) was 59%. Median PFS was 4.3 (95% CI, 3.0-10.9) months, with a six month PFS rate of 43%. Median OS after current relapse was 8.9 (95% CI, 5.8-not reached) months. Ten episodes of grade 3/4 adverse events were observed in nine patients, including fatigue (n = 3), thrombocytopenia (n = 4), and myelotoxicity, febrile neutropenia, and pulmonary embolism (each n = 1). CONCLUSIONS: We consider the efficacy and safety profile of bevacizumab is comparable to other cohorts of patients treated for recurrent high-grade glioma at other international institutions. PURPOSE: To describe the quality of life (QOL) in elderly patients with glioblastoma (GBM) treated with an abbreviated course of radiation therapy (RT; 40 Gy in 15 fractions) plus concomitant and adjuvant temozolomide (TMZ). METHODS AND MATERIALS: Health-related QOL (HRQOL) was assessed by European Organisation for Research and Treatment of Cancer (EORTC) Quality of Life Questionnaire Core-30 (QLQ-C30, version 3) and EORTC Quality of Life Questionnaire Brain Cancer Module (QLQ-BN20). Changes from baseline in the score of 9 preselected domains (global QLQ, social functioning, cognitive functioning, emotional functioning, physical functioning, motor dysfunction, communication deficit, fatigue, insomnia) were determined 4 weeks after RT and thereafter every 8 weeks during the treatment until disease progression. The proportion of patients with improved HRQOL scores, defined as a change of 10 points or more, and duration of changes were recorded. RESULTS: Sixty-five patients completed the questionnaires at baseline. The treatment was consistently associated with improvement or stability in most of the preselected HRQOL domains. Global health improved over time; mean score differed by 9.6 points between baseline and 6-month follow-up (P=.03). For social functioning and cognitive functioning, mean scores improved over time, with a maximum difference of 10.4 points and 9.5 points between baseline and 6-month follow-up (P=.01 and P=.02), respectively. By contrast, fatigue worsened over time, with a difference in mean score of 5.6 points between baseline and 4-month follow-up (P=.02). CONCLUSIONS: A short course of RT in combination with TMZ in elderly patients with GBM was associated with survival benefit without a negative effect on HRQOL until the time of disease progression.
List two common features of Tay syndrome.
Tay syndrome is a rare autosomal recessive genetic disorder characterized by congenital ichthyosis and trichothiodystrophy (abnormal brittle hair). Other less common features of this syndrome are photosensitivity, low birth weight, short stature, mental retardation, delayed neuromuscular development and other CNS anomalies, dysplasia of nails, hypoplasia of subcutaneous fatty tissue, prematurely aged facial appearance, hypogonadism, cataracts, osteosclerosis, dysphonia, and increased susceptibility to infections.
Trichothiodystrophy (brittle sulfur-deficient hair) is a marker for several autosomal recessive neurocutaneous syndromes with neurological manifestations and mental retardation. In Tay syndrome, the trichothiodystrophy is accompanied by congenital ichthyosis, short stature, delayed physical and mental development and pyramidal tract signs with increase in muscular tone and brisk tendon reflexes. The pathogenesis of these neurological manifestations is not fully elucidated. We present a case of Tay syndrome in which a cranial MRI revealed an almost total lack of myelin within the cerebral hemispheres and a patchy hypomyelination of the cerebellum. In accordance, a strongly prolonged visual evoked response pointed to a dysfunction of the white matter in Tay syndrome. This paper reports on the orthopaedic rehabilitation of a patient with Tay-syndrome. Tay-syndrome is a rare monogen-inherited ektodermal dysplastic syndrome with ichtyosis, fragility of the hair and physical and mental retardation. The congenital ichtyosis is ubiquitous. Only the skin on the flexion side of the extremity joints are not involved (orthocerathosis combined with paraceratotic strings). In this case, a young boy developed bilateral subluxation of the hips and was not able to stand or walk freely. Contemporary pre- and neonatal care has prolonged the survival of newborns with severe genodermatoses, including this syndrome. In this case, it has provided the necessity for orthopaedic treatment of the problems caused by osteosclerosis and muscular spasticity. Trichothiodystrophy comprises a heterogeneous group of autosomal recessive entities. This fact gives rise to different interrelated neuroectodermal disorders. From a structural point of view these features are the result of the low tissue sulfur content. We report a case of trichothiodystrophy initially classified as Tay syndrome that based on clinical features, complementary exams as well as on the disease evolution was labelled as PIBIDS syndrome. Tay syndrome or IBIDS is a rare autosomal recessive genetic disorder characterized by congenital ichthyosis and abnormal brittle hair (trichothiodystrophy). Other features include photosensitivity, abnormal nails and multiple developmental defects affecting organs mainly derived from neuroectoderm. The exact prevalence of this condition is not known, but up to 1991, clinical data of 15 cases with IBIDS were published .We report a case of Tay syndrome with additional features of Duane's retraction syndrome and Perthes disease, which have not yet been reported in literature.
Which cell types are known to be driving Rheumatoid Arthritis?
Macrophages, T cells and their respective cytokines play a pivotal role in RA. Rheumatoid arthritis synovial fibroblasts (RASFs) constitute a quite unique cell type that distinguishes RA from other inflammatory conditions of the joints. Activated synovial fibroblasts (SFs) have the ability to invade joint cartilage, actively contributing to joint destruction in RA.
The proteins of homeobox (HOX) genes are transcription regulators involved in cell type-specific differentiation and patterning of the body plan in vertebrates. Particularly, the HOXD family is involved in limb formation in mice and chicks. There is also some evidence that the HOXD9 gene, a member of the HOXD family, is involved in the pathology of rheumatoid arthritis (RA). The purpose of the present study was to determine if the HOXD9 protein was expressed in RA synovium and then to characterize the HOXD9-expressing cell. Western blotting and immunohistochemical analysis showed that the HOXD9 protein was expressed in the synovium from patients with RA, but not in those from patients with osteoarthritis or healthy individuals. The HOXD9-positive cells were localized in both the lining and sublining areas of the synovium. Furthermore, fluorescent double-staining showed that the HOXD9 protein was expressed in fibroblast-like synoviocytes (FLS). These findings not only indicate that the HOXD9 gene is exclusively expressed in the RA synovium but also suggest that the HOXD9 gene contributes to the pathology of rheumatoid arthritis through the FLS. OBJECTIVE: Treatment of rheumatoid arthritis (RA) with tumor necrosis factor (TNF) antagonists is highly effective, but their mechanisms of action are not completely clear. Since anti-TNF therapy induces a decrease in synovial cellularity, this study focused on the modulation of RA synovial apoptosis following treatment with either soluble TNF receptor (etanercept) or TNF chimeric monoclonal antibody (infliximab). METHODS: Apoptosis (TUNEL and active caspase 3 staining) and cell surface markers were evaluated by immunohistochemistry in synovial biopsy samples obtained before and after 8 weeks of treatment with etanercept (12 patients) or infliximab (9 patients). We also determined by flow cytometry the in vitro effect of etanercept and infliximab on apoptosis of RA mononuclear cells derived from the synovial fluid (SF) and peripheral blood (PB). RESULTS: Eight weeks of treatment with etanercept and with infliximab significantly increased synovial apoptosis. This change was accompanied by a significant decrease in the synovial monocyte/macrophage population. The decrease in lymphocyte numbers did not reach statistical significance. In vitro, 24 hours of incubation with either etanercept or infliximab induced apoptosis of the SF monocyte/macrophage population. PB monocyte/macrophages were less susceptible to anti-TNF-mediated apoptosis. No changes in the rate of apoptosis were observed in the lymphocyte population derived from either SF or PB. CONCLUSION: In RA patients, both etanercept and infliximab are able to induce cell type-specific apoptosis in the monocyte/macrophage population. This suggests a potential pathway that would account for the diminished synovial inflammation and the decreased numbers of synovial macrophages evident after TNF blockade. Rheumatoid arthritis (RA) is a chronic autoimmune-disease of unknown origin that primarily affects the joints and ultimately leads to their destruction. The involvement of immune cells is a general hallmark of autoimmune-related disorders. In this regard, macrophages, T cells and their respective cytokines play a pivotal role in RA. However, the notion that RA is a primarily T-cell-dependent disease has been strongly challenged during recent years. Rather, it has been understood that resident, fibroblast-like cells contribute significantly to the perpetuation of disease, and that they may even play a role in its initiation. These rheumatoid arthritis synovial fibroblasts (RASFs) constitute a quite unique cell type that distinguishes RA from other inflammatory conditions of the joints. A number of studies have demonstrated that RASFs show alterations in morphology and behaviour, including molecular changes in signalling cascades, apoptosis responses and in the expression of adhesion molecules as well as matrix-degrading enzymes. These changes appear to reflect a stable activation of RASFs, which occurs independently of continuous exogenous stimulation. As a consequence, RASFs are no longer considered passive bystanders but active players in the complex intercellular network of RA. Rheumatoid arthritis (RA) is characterized by the recruitment of leukocytes and the accumulation of inflammatory mediators within the synovial compartment. Release of the chemokine CCL18 has been widely attributed to antigen-presenting cells, including macrophages and dendritic cells. This study investigates the production of CCL18 in polymorphonuclear neutrophils (PMN), the predomit cell type recruited into synovial fluid (SF). Microarray analysis, semiquantitative and quantitative reverse transcriptase polymerase chain reaction identified SF PMN from patients with RA as a novel source for CCL18 in diseased joints. Highly upregulated expression of other chemokine genes was observed for CCL3, CXCL8 and CXCL10, whereas CCL21 was downregulated. The chemokine receptor genes were differentially expressed, with upregulation of CXCR4, CCRL2 and CCR5 and downregulation of CXCR1 and CXCR2. In cell culture experiments, expression of CCL18 mRNA in blood PMN was induced by tumor necrosis factor alpha, whereas synthesis of CCL18 protein required additional stimulation with a combination of IL-10 and vitamin D3. In comparison, recruited SF PMN from patients with RA were sensitized for CCL18 production, because IL-10 alone was sufficient to induce CCL18 release. These results suggest a release of the T cell-attracting CCL18 by PMN when recruited to diseased joints. However, its production is tightly regulated at the levels of mRNA expression and protein synthesis. Fibroblast-like synoviocytes (FLS) are resident mesenchymal cells of synovial joints that have been recognized to play an increasingly important role in the pathogenesis of rheumatoid arthritis (RA). Activation of FLS in the setting of RA leads to the production of a broad array of cell surface and soluble mediators that help to recruit, retain, and activate both cells of the immune system and resident joint cells, leading to the promotion of ongoing inflammation and tissue destruction. The ability of FLS to stimulate both inflammation and tissue damage suggests that this cell type may be a unique target for the treatment of inflammatory arthritis. Greater understanding of how FLS are activated and how they interact with other cells in the RA synovium may provide insights that allow development of novel agents for RA therapy. Mesenchymal stromal cells (MSCs) represent a unique cell type with anti-proliferative effects on activated T and B cells. Based on our observation of differences between rheumatoid arthritis and osteoarthritis bone marrow B cells we hypothesized that rheumatoid arthritis bone marrow MSCs may enhance B-cell survival. We aimed to compare the effect of rheumatoid arthritis and osteoarthritis bone marrow-derived MSCs (rheumatoid arthritis MSCs, osteoarthritis MSCs) on the survival of healthy donor purified B cells. Rheumatoid arthritis and osteoarthritis MSCs were isolated from patients undergoing hip replacement surgery, and cultured in vitro for 2-5 passages. Washed cells were co-cultured with CD20+ B cells for 30-90 hours. Cell survival was analysed using 7-amino-actinomycin D labelling by flow cytometry. Expression of mRNA and protein was determined by RT-PCR and flow cytomery. Co-culture with both rheumatoid arthritis MSCs and osteoarthritis MSCs significantly enhanced B-cell survival, the effect being more prominent in rheumatoid arthritis MSCs. Both types of MSCs displayed expression of B cell-activating factor mRNA and protein. Blocking B cell-activating factor signalling from MSCs by specific anti-B cell-activating factor and anti-B cell-activating factor receptor antibodies weakly reversed the effect of MSCs on B-cell survival mainly in rheumatoid arthritis MSCs. MSC interaction with B cells provides stimuli for B-cell survival and therefore may contribute to the pathogenesis of rheumatoid arthritis. MSC-derived factors other than B cell-activating factor are likely to contribute to this effect. This feature is more prominent in rheumatoid arthritis MSCs, possibly due to the B cell-activating factor. Cell migration is a central part of physiological and pathophysiological processes including wound healing, immune defense, matrix remodeling and organ homeostasis. Different cell types have migratory potential including cells of the immune system and cells required in wound healing and tissue repair. These cells migrate locally through the tissue to the site of damage. The fibroblast is a central cell type of wound healing. In rheumatoid arthritis (RA), activated synovial fibroblasts (SFs) have the ability to invade joint cartilage, actively contributing to joint destruction in RA. Recently, RASFs have been shown to be able to migrate to non-affected areas and joints through the blood stream and to invade distant cartilage. RASFs most likely use similar mechanisms comparable to lymphocytes and tumor cells for long-distance and vascular trans-migration. Future experiments will address the goal to keep the transformed-appearing fibroblasts in the affected joints using therapeutical strategies that inhibit the pathophysiological changes of transformed-appearing RASFs but do not interfere with the physiological processes of 'normal' fibroblasts. IL-1R-associated kinases (IRAKs) are important mediators of MyD88-dependent signaling by the TLR/IL-1R superfamily and facilitate inflammatory responses. IRAK4 and IRAK1 function as active kinases and as scaffolds for protein-protein interactions. We report that although IRAK1/4 kinase activity is essential for human plasmacytoid dendritic cell (pDC) activation, it is dispensable in B, T, dendritic, and monocytic cells, which is in contrast with an essential active kinase role in comparable mouse cell types. An IRAK1/4 kinase inhibitor abrogated TLR7/9-induced IFN-α responses in both mouse and human pDCs, but other human immune cell populations activated via TLR7/9 or IL-1R were refractory to IRAK4 kinase inhibition. Gene ablation experiments using small interfering RNA demonstrated an essential scaffolding role for IRAK1 and IRAK4 in MyD88-dependent signaling. Finally, we demonstrate that autoimmune patient (systemic lupus erythematosus and rheumatoid arthritis) serum activates both pDC and B cells, but IRAK1/4 kinase inhibition affects only the pDC response, underscoring the differential IRAK1/4 functional requirements in human immune cells. These data reveal important species differences and elaborate cell type requirements for IRAK1/4 kinase activity. PURPOSE OF REVIEW: A significant number of loci implicated in rheumatoid arthritis (RA) susceptibility have been highlighted by genome-wide association studies (GWAS). Here, we review the recent advances of GWAS in understanding the genetic architecture of RA, and place these findings in the context of RA pathogenesis. RECENT FINDINGS: Although the interpretation of GWAS findings in the context of the disease biology remains challenging, interesting observations can be highlighted. Integration of GWAS results with cell-type specific gene expression or epigenetic marks have highlighted regulatory T cells and CD4 memory T cells as critical cell types in RA. In addition, many genes in RA loci are involved in the nuclear factor-kappaB signaling pathway or the Janus kinase (JAK)-signal transducers and activators of transcription (STAT) signaling pathway. The observation that these pathways are targeted by several approved drugs used to treat the symptoms of RA highlights the promises of human genetics to provide insights in the disease biology, and help identify new therapeutic targets. SUMMARY: These findings highlight the promises and need of future studies investigating causal genes and underlined mechanisms in GWAS loci to advance our understanding of RA.
What is the association between personality trait of neuroticism and risk for Alzheimer's disease?
High neuroticism is associated with increased risk to develop Alzheimer's disease. Greater neuroticism is also associated more advanced Alzheimer's disease neuropathology and younger age of dementia onset. Neuroticism's association with late-life dementia mainly reflects vulnerability to stress and anxiety. Neuroticism moderates the relationship between APOE-4 genotype and cognitive outcomes in elderly. Neuroticism also predicts Mild Cognitive Impairment, Aging-Associated Cognitive Decline and cognitive decline among elderly. Alzheimer's disease patients have greater neuroticism relative to controls.
Using the NEO Personality Inventory (NEO-PI), we evaluated caregivers' perceptions of personality prior to symptom onset and current personality in 36 individuals with a clinical diagnosis of dementia of the Alzheimer's type (DAT). Caregivers also completed the self form of the NEO-PI and an index of objective and subjective burden. Personality change in DAT was consistent with previous reports of increased neuroticism, decreased extraversion, and decreased conscientiousness, with smaller decreases in openness and agreeableness. Significant relationships were found among perceived present patient personality, caregiver personality, and caregiver burden. Regression analyses indicated that present patient conscientiousness and caregiver neuroticism were the best predictors of both objective and subjective burden, and these variables were found to contribute independently to caregivers' reported level of burden. To the extent that caregivers perceive specific behaviors and interferences negatively, cognitive and supportive interventions are likely to prove extremely beneficial. OBJECTIVE: To identify specific premorbid personality traits in patients with Alzheimer's disease (AD). DESIGN: A prospective case-control study. SETTING: A memory clinic of a department of geriatric medicine in a teaching hospital. PATIENTS: Fifty-six consecutive patients with probable AD. Sixty-five controls with Parkinson's disease (PD). MEASURES: Premorbid personality traits were assessed using the relative rating version of the Munich Personality Test (MPT). RESULTS: The AD patients showed higher neuroticism than the controls with PD (p=0.013). In comparison with MPT normative values for psychiatric inpatients, the AD patients scored significantly (p<0.05) lower on neuroticism and higher on frustration tolerance and rigidity. CONCLUSION: Our results support the assumption of specific premorbid characteristics in AD patients, ie increased neuroticism and rigidity. More research is needed to confirm the existence of typical premorbid personality traits in AD. Studying the cognitive and immunological changes that occur in old age as well as genetic function have been considered an important subject to differentiate between normal brain aging and early dementia especially Alzheimer's disease. The aim of this study is to stress on age-related neuropsychological and electrophysiological (P(300)) changes in normal Egyptian subjects, to throw light on the value of genetic (Apo-E(4) genotype) and immunological markers [interleukin-6 (IL-6) and intercellular adhesion molecules (ICAM-1) in the serum] as tools used in early detection of cognitive decline in cerebral aging. Ninety-four normal Egyptian subjects (below and above 60 years) were submitted to the following: (1) neuropsychological tests for testing memory, perception, psychomotor performance and attention, (2) Eysenck Personality Questionnaire (EPQ) for personality traits, (3) event-related potential study (P(300), latency and amplitude), (4) genetic test for detection of Apolipoprotein E genotype and (5) immunological studies including detection of the level of IL-6 and ICAM-1 in serum. There was a significant impairment of memory, psychomotor performance and perception in elderly subjects particularly males and subjects with low level of education. Regarding personality, significantly high scores were obtained in neuroticism scale of EPQ in elderly subjects. Apo-E(3)/E(3) was the most common genotype encountered in Egyptian subjects (49.1%). It was found that subjects with Apo-E(4) genotype did significantly worse in scores of intentional memory test (sensory memory) when compared with other genotypes. Statistically significant impairment in attention and sensory memory was found in subjects with high IL-6 level. This could not be detected in subjects with high ICAM-1 level. In conclusion, advancing age and lower levels of education are considered risk factors for cognitive decline in normal brain aging. Neuropsychological tests remain as the highly sensitive tools for detection of early cognitive impairment. Neurotic traits are more encountered in old age. Apo-E(4) genotype is associated with significant sensory (intentional) memory impairment. High IL-6 level in the serum is accompanied by significant impairment in attention and sensory (intentional) memory. The association between distress proneness and cognitive decline was examined in older residents of a biracial community in Chicago. At baseline, participants completed four cognitive tests that yielded a global measure (baseline mean=101.2; standard deviation (SD)=7.8), and a brief measure of the tendency to experience negative emotions (mean=16.5; SD=6.7) based on the Neuroticism scale of the NEO Five-Factor Inventory. Cognitive testing was repeated twice at three-year intervals. In mixed models that controlled age, sex, race, and education, for each point on the distress proneness scale, global cognitive score was 0.12 unit lower at baseline (p<0.001) and annual rate of decline increased by 0.01 unit (p=0.002), or about 2%. Thus, cognitive decline was about 30% faster in a person highly prone to distress (score=24, 90th percentile) compared to the one low in distress proneness (score=9, 10th percentile). This effect was unchanged after controlling for level of cognitive activity or excluding people with cognitive impairment at baseline, but it was reduced to a trend (p=0.059) after controlling for depressive symptoms. The results suggest that the tendency to experience psychological distress is associated with increased cognitive decline in old age. OBJECTIVE: The objective of this study was to test the association of the personality traits of neuroticism and extraversion with risk of death in old age. METHODS: A census was taken of a geographically defined urban community in Chicago, and those aged 65 years or older were invited to participate in an in-home interview; 6158 (79% of those eligible) did so. The interview included brief measures of neuroticism and extraversion, medical history, and questions about current participation in cognitive, social, and physical activities. Vital status was subsequently monitored. The association of each trait with risk of death was examined in a series of accelerated failure-time models that controlled for age, sex, race, and education. RESULTS: During a mean of more than 6 years of observation, 2430 persons (39.5%) died. A high level of neuroticism (score = 27; 90th percentile) was associated with a 33% increase in risk of death compared with a low level of neuroticism (score = 9; 10th percentile). A high level of extraversion (score = 33; 90th percentile) was associated with a 21% decrease in risk of death compared with a low level (score = 18; 10th percentile). Adjustment for medical conditions and health-related variables did not substantially affect results, but adjusting for baseline levels of cognitive, social, and physical activity reduced the association of both traits with mortality. CONCLUSIONS: The results suggest that higher extraversion and lower neuroticism are associated with reduced risk of mortality in old age and that these associations are mediated in part by personality-related patterns of cognitive, social, and physical activity. Clinical and pathological data from the Rush Memory and Aging Project were used to test the hypothesis that distress proneness is associated with increased risk of Alzheimer's disease (AD). More than 600 older persons without dementia completed a 6-item measure of neuroticism, a stable indicator of proneness to psychological distress. At annual intervals thereafter, they underwent uniform evaluations that included clinical classification of AD and administration of 18 cognitive tests. Those who died underwent brain autopsy from which composite measures of AD pathology were derived. During a mean of about 3 years of follow-up, 55 people were clinically diagnosed with AD. In analyses that controlled for age, sex, and education, persons with a high level of distress proneness (score = 24, 90th percentile) were 2.7 times more likely to develop AD than those not prone to distress (score = 6, 10th percentile). Adjustment for depressive symptomatology or frequency of cognitive, social, and physical activity did not substantially change this effect. Distress proneness was also associated with more rapid cognitive decline. Among 45 participants who died and underwent brain autopsy, distress proneness was unrelated to diverse measures of AD pathology and was inversely related to cognition after controlling for AD pathology. The results support the hypothesis that distress proneness is associated with increased risk of dementia and suggest that neurobiologic mechanisms other than AD pathology may underlie the association. OBJECTIVE: The objective of this study was to test whether common age-related neuropathology could account for the relation of chronic distress to dementia. METHODS: In a selected cohort of more than 1000 older Catholic clergy members undergoing annual clinical evaluations, 326 persons died, of whom 306 (94%) underwent brain autopsy, the results of which were available in 219 (mean age at death = 85.4, standard deviation [SD] = 6.6; mean postmortem interval = 7.6 hours, SD = 6.9). A composite measure of chronic distress was constructed from standard measures of two traits, neuroticism and anxiety proneness, completed at baseline, and of depressive symptoms, completed annually. Dementia was diagnosed according to standard criteria and cognition was assessed with previously established composite measures based on a uniform clinical evaluation that took place a mean of 9.1 months before death (SD = 9.5). On postmortem examination, levels of amyloid-beta and tau-positive neurofibrillary tangles and the presence of Lewy bodies were quantified in six brain regions, and the number and location of chronic cerebral infarctions were noted. RESULTS: In analyses that controlled for age, sex, education, amyloid, tangles, Lewy bodies, and cerebral infarction, higher level of chronic distress was associated with a higher likelihood of dementia and lower level of cognition proximate to death. Chronic distress was not correlated with any form of neuropathology, including limbic, neocortical, and global indices, and did not modify the association of pathology with cognition. CONCLUSIONS: Chronic psychological distress is associated with late-life dementia but not with its leading causes, suggesting that novel neurodeteriorative mechanisms may be involved. BACKGROUND: There may be important public health implications of increasing our knowledge of factors associated with age of dementia onset. The pre-morbid personality domain of Neuroticism constituted an interesting and theoretically plausible, yet uninvestigated, candidate for such an association. We aimed to examine whether midlife Neuroticism was associated with earlier age of onset of Alzheimer's disease (AD). METHOD: This was a case-comparison study of 213 patients with probable AD. Detailed clinical information was collected for all patients including age of onset of dementia symptoms. One or two knowledgeable informants rated each patient's midlife personality retrospectively using the Neuroticism, Extraversion, Openness Five-Factor Inventory (NEO-FFI) questionnaire. The relationship between midlife Neuroticism and age of dementia onset was evaluated using both correlational analysis and backward linear regression analysis. RESULTS: Midlife Neuroticism predicted younger age of dementia onset in females but not in males. The association found in females was independent of pre-morbid history of affective disorder. CONCLUSIONS: This finding and its potential mechanism warrant further investigation. OBJECTIVE: High neuroticism has been associated with a greater risk of dementia, and an active/socially integrated lifestyle with a lower risk of dementia. The aim of the current study was to explore the separate and combined effects of neuroticism and extraversion on the risk of dementia, and to examine whether lifestyle factors may modify this association. METHODS: A population-based cohort of 506 older people with no dementia from the Kungsholmen Project, Stockholm, Sweden, was followed up for an average of 6 years. Personality traits were assessed using the Eysenck Personality Inventory. Dementia was diagnosed by specialists according to DSM-III-R criteria. RESULTS: Neither high neuroticism nor low extraversion alone was related to significantly higher incidence of dementia. However, among people with an inactive or socially isolated lifestyle, low neuroticism was associated with a decreased dementia risk (hazard ratio [HR] = 0.51, 95% confidence interval [CI] = 0.27-0.96). When compared to persons with high neuroticism and high extraversion, a decreased risk of dementia was detected in individuals with low neuroticism and high extraversion (HR = 0.51, 95% CI = 0.28-0.94), but not among persons with low neuroticism and low extraversion (HR = 0.95, 95% CI = 0.57-1.60), nor high neuroticism and low extraversion (HR = 0.97 95% CI = 0.57-1.65). Stratified analysis by lifestyle showed that the inverse association of low neuroticism and high extraversion in combination was present only among the inactive or socially isolated persons. CONCLUSION: Low neuroticism in combination with high extraversion is the personality trait associated with the lowest dementia risk; however, among socially isolated individuals even low neuroticism alone seems to decrease dementia risk. [Correction Notice: An erratum for this article was reported in Vol 26(2) of Psychology and Aging (see record 2011-05802-001). This article contains an error in the Discussion, under the Implications, Caveats, Future Directions heading. The third paragraph includes the sentences that should have been removed. The corrected paragraph appears in the correction.] We conducted secondary analyses to determine the relationship between longstanding personality traits and risk for Alzheimer's disease (AD) among 767 participants 72 years of age or older who were followed for more than 6 years. Personality was assessed with the NEO-FFI. We hypothesized that elevated Neuroticism, lower Openness, and lower Conscientiousness would be independently associated with risk of AD. Hypotheses were supported. The finding that AD risk is associated with elevated Neuroticism and lower Conscientiousness can be added to the accumulating literature documenting the pathogenic effects of these two traits. The link between lower Openness and AD risk is consistent with recent findings on cognitive activity and AD risk. Findings have implications for prevention research and for the conceptualization of the etiology of AD. OBJECTIVE: To identify the components of the neuroticism trait most responsible for its association with cognitive decline and dementia in old age. DESIGN: Longitudinal clinical-pathologic cohort study. SETTING: Chicago metropolitan area. PARTICIPANTS: A total of 785 older persons without dementia completed standard self-report measures of six components of neuroticism and then had annual clinical evaluations for a mean of 3.4 years and brain autopsy in the event of death. MEASUREMENTS: Incidence of clinically diagnosed Alzheimer disease (AD), change in global and specific cognitive functions, and postmortem measures of plaques and tangles, cerebral infarction, and Lewy bodies. RESULTS: During follow-up, 94 individuals developed AD. Higher levels of anxiety and vulnerability to stress were associated with increased risk of AD and more rapid decline in global cognition, with no effects for the other four trait components. In analyses of specific cognitive systems, neuroticism subscales were related to decline in episodic memory, working memory, and perceptual speed, but not in semantic memory or visuospatial ability. No component of neuroticism was related to the neuropathologic lesions most commonly associated with late-life dementia. CONCLUSIONS: Neuroticism's association with late-life dementia mainly reflects vulnerability to stress and anxiety and their correlation with decline in the ability to process and retain new information. OBJECTIVE: To investigate personality traits in patients with Alzheimer disease, compared with mentally healthy control subjects. We compared both current personality characteristics using structured interviews as well as current and previous personality traits as assessed by proxies. METHOD: Fifty-four patients with mild Alzheimer disease and 64 control subjects described their personality traits using the Structured Interview for the Five-Factor Model. Family members filled in the Revised NEO Personality Inventory, Form R, to evaluate their proxies' current personality traits, compared with 5 years before the estimated beginning of Alzheimer disease or 5 years before the control subjects. RESULTS: After controlling for age, the Alzheimer disease group presented significantly higher scores than normal control subjects on current neuroticism, and significantly lower scores on current extraversion, openness, and conscientiousness, while no significant difference was observed on agreeableness. A similar profile, though less accentuated, was observed when considering personality traits as the patients' proxies remembered them. Diachronic personality assessment showed again significant differences between the 2 groups for the same 4 domains, with important personality changes only for the Alzheimer disease group. CONCLUSIONS: Group comparison and retrospective personality evaluation are convergent. Significant personality changes follow a specific trend in patients with Alzheimer disease and contrast with the stability generally observed in mentally healthy people in their personality profile throughout their lives. Whether or not the personality assessment 5 years before the current status corresponds to an early sign of Alzheimer disease or real premorbid personality differences in people who later develop Alzheimer disease requires longitudinal studies. OBJECTIVE: People with Alzheimer's disease (AD) commonly exhibit changes in personality that sometimes precede the other early clinical manifestations of the condition, such as cognitive impairment and mood changes. Although these personality changes reflect the impact of progressive brain damage, there are several possible patterns of personality change with dementia. Early identification of personality change might assist with the timely diagnosis of AD. The objective of this study was to review studies of personality change in AD. METHODS: Systematic searches of the PubMed, Ovid Medline, EBSCOhost, PsychINFO and CINAHL databases were undertaken from inception to November 2009. Published studies of informant-rated personality traits in AD patients were identified. Studies that mapped changes in traits from the five-factor model of personality which includes factors for Neuroticism, Extraversion, Openness, Agreeableness and Conscientiousness, were selected for analysis. The change in each of these five traits was calculated as the mean difference in score before and after the diagnosis of AD. RESULTS: There was a mean increase in Neuroticism of 10-20 T scores (equivalent to 1-2 SD), a decrease of the same magnitude in Extraversion, consistently reduced Openness and Agreeableness, and a marked decrease in Conscientiousness of about 20-30 T scores (equivalent to 2-3 SD). These changes were systematic and consistent. Particularly striking was the similarity of both the magnitude and direction of change in all studies reviewed. CONCLUSIONS: Conscientiousness and Neuroticism are the personality traits that exhibit the most change in dementia. These traits might be useful early markers of dementia. We examined the association of social activity with cognitive decline in 1138 persons without dementia at baseline with a mean age of 79.6 (SD = 7.5) who were followed for up to 12 years (mean = 5.2; SD = 2.8). Using mixed models adjusted for age, sex, education, race, social network size, depression, chronic conditions, disability, neuroticism, extraversion, cognitive activity, and physical activity, more social activity was associated with less cognitive decline during average follow-up of 5.2 years (SD = 2.7). A one point increase in social activity score (range = 1-4.2; mean = 2.6; SD = 0.6) was associated with a 47% decrease in the rate of decline in global cognitive function (p < .001). The rate of global cognitive decline was reduced by an average of 70% in persons who were frequently socially active (score = 3.33, 90th percentile) compared to persons who were infrequently socially active (score = 1.83, 10th percentile). This association was similar across five domains of cognitive function. Sensitivity analyses revealed that individuals with the lowest levels of cognition or with mild cognitive impairment at baseline did not drive this relationship. These results confirm that more socially active older adults experience less cognitive decline in old age. OBJECTIVES: We tested the hypothesis that neuroticism moderates the association between APOE (apolipoprotein E) genotype and two major outcomes, cognitive function and Alzheimer disease. We also explored whether other personality dimensions (extraversion, openness to experience, agreeableness, and conscientiousness) moderate the associations of APOE with these outcomes. DESIGN: Primary analyses of existing randomized clinical trial data. SAMPLE: Six-hundred two older adults (mean age of 78 years at baseline). MEASUREMENTS: APOE genotype, the NEO-Five Factor Inventory, the Alzheimer's Disease Assessment Scale-Cognitive: measured every 6 months for 6.5 years) and relevant covariates. RESULTS: Fully adjusted multivariate analyses showed that the association between the presence of APOE [Latin Small Letter Open E]-4 allele(s) and both outcomes was evident among individuals with high levels of neuroticism and extraversion but not among persons with low levels of these traits. CONCLUSIONS: Phenotypic personality dimensions, primarily neuroticism and extraversion, moderate the relationship between APOE [Latin Small Letter Open E]-4 genotype and cognitive outcomes among older adults. Future research is needed to elucidate the physiological processes involved in these particular phenotype-genotype interactions.
What is the mode of action of everolimus?
Everolimus is a drug that binds to mTORC1 and inhibits activation of the mTOR signalling pathway. It is used in targeted cancer therapy protocols or after transplantation for maintenance immunosuppression, against allograft rejection.
BACKGROUND: Target of rapamycin inhibitors (TOR-I) have a novel mode of action but uncertain clinical role. We performed a systematic review of randomized trials where immunosuppressive regimens containing TOR-I were compared with other regimens as initial therapy for kidney transplant recipients. METHODS: Databases (inception, June 2005) and conference proceedings (1996-2005) were searched. Two independent reviewers assessed trials for eligibility and quality. Results at 1 year, are expressed as relative risk (RR), where values<1 favor TOR-I, or lower dose of TOR-I, and for continuous outcomes are expressed as weighted mean difference (WMD), both expressed with 95% confidence intervals (CI). RESULTS: Thirty-three trials (142 reports) were included (27 trials of sirolimus, 5 of everolimus, and 1 of head-to-head comparison). When TOR-I replaced calcineurin inhibitors (CNI) (8 trials with 750 participants), there was no difference in acute rejection (RR, 1.03; 95% CI, 0.74-1.44), but serum creatinine was lower (WMD, -18.31 micromol/L; 95% CI, -30.96 to -5.67) and bone marrow more suppressed (leukopenia: RR 2.02; 95% CI, 1.12-3.66; thrombocytopenia: RR, 6.97; 95% CI, 2.97-16.36; and anaemia: RR, 1.67; 95% CI, 1.27-2.20). When TOR-I replaced antimetabolites (11 trials with 3966 participants), acute rejection and cytomegalovirus infection (CMV) were reduced (RR, 0.84; 95% CI, 0.71-0.99; RR, 0.49; 95% CI, 0.37-0.65, respectively), but hypercholesterolemia was increased (RR, 1.65; 95% CI, 1.32-2.06). When low- was compared with high-dose TOR-I, with equal CNI dose (10 trials with 3,175 participants), rejection was increased (RR, 1.23; 95% CI, 1.06-1.43) but calculated glomerular filtration rate (GFR) higher (WMD, 4.27 mL/min; 95% CI, 1.12-7.41), and when lower-dose TOR-I and standard-dose CNI were compared with higher-dose TOR-I and reduced CNI, acute rejection was reduced (RR, 0.67; 95% CI, 0.52-0.88), but calculated GFR was also reduced (WMD, -9.46 mL/min; 95% CI, -12.16 to -6.76). There was no significant difference in mortality, graft loss, or maligcy risk for TOR-I in any comparison. CONCLUSIONS: TOR-I have been evaluated in four different primary immunosuppressive algorithms: as replacement for CNI and antimetabolites, in combination with CNI at low and high doses, and with a variable dose of CNI. Generally, surrogate endpoints for graft survival favor TOR-I (lower risk of acute rejection and higher GFR), and surrogate endpoints for patient outcomes are worsened by TOR-I (bone marrow suppression and lipid disturbance). Long-term hard-endpoint data from methodologically robust randomized trials are still required. Acute rejection episodes are now as low as 5-20% in the first year after renal transplantation; however, graft half-life has remained almost unchanged in the last decade. This statistic is mainly attributable to the side effects of immunosuppression, with loss of allografts due to the chronic allograft nephropathy that is a consequence of calcineurin inhibitor toxicity or hypertension. Patient death due to cardiovascular events, infections and maligcy also contribute to allograft loss. The introduction of the inhibitors of the mammalian target of rapamycin sirolimus and everolimus in renal transplantation has increased the repertoire of immunosuppressive protocols substantially. They have a different mode of action and a different side effect profile (i.e. lower nephrotoxicity, less hypertension and less neoplastic potential) than the calcineurin inhibitors. The inhibitors of the mammalian target of rapamycin therefore provide an especially promising alternative for the maintece immunosuppression after renal transplantation. This overview provides a summary of the current literature on inhibitors of the mammalian target of rapamycin, with a special focus on sirolimus. BACKGROUND/AIM: The mode of action of the somatostatin analog octreotide on neuro-endocrine tumour proliferation is largely unknown. Overexpression of the proto-oncogene Akt/PKB (protein kinase B) has been demonstrated in certain neuro-endocrine tumours: Akt activates downstream proteins including mTOR and p70S6K, which play an important role in cell proliferation. RAD001 (everolimus) is a novel agent that is being trialled in the treatment of neuro-endocrine tumours, and is known to interact with mTOR. We explored the mechanism of action of octreotide, RAD001, and their combination on cell proliferation and kinase activation in a neuro-endocrine tumour cell line (rat insulinoma cell line, INS1). METHODS: Proliferation assays were used to determine the effects of octreotide, RAD001, and their combination on cell proliferation. Western blotting was used to characterize the expression of phosphorylated Akt, phosphorylated TSC2, phosphorylated mTOR, and phosphorylated 70S6K. RESULTS: Treatment with octreotide and RAD001 inhibited proliferation and attenuated phosphorylation of all downstream targets of Akt: TSC2, mTOR, and p70S6K. CONCLUSIONS: In this cell model, octreotide and RAD001 appear to act through a similar pathway and inhibit the Akt-mTOR-p70S6 kinase pathway downstream of Akt. There may be some overlapping effects of the two inhibitors on the mTOR pathway, although it is likely that other additional effects may differentiate the two agents. Targeted therapies are widely used in cancer because of their effectiveness, even in tumours that are resistant to conventional chemotherapy such as kidney or hepatocellular carcinomas. There are different families classified according to their mode of action. The antiangiogenics block tumor angiogenesis by acting on VEGF or its receptor. The main molecules are bevacizumab, sunitinib, and sorafinib. HER inhibitors work by blocking these receptors, which control different signaling intracellular pathways, and include an inhibitor of HER2, trastuzumab, and various inhibitors of HER1, or EGFR, including cetuximab, erlotinib, and gefitinib. Inhibitors of KIT, a membrane receptor, are mainly represented by imatinib, an inhibitor of tyrosine kinase. Finally, mTOR inhibitors act on the signaling pathway PI3K/AKT/mTOR, and key molecules are temsirolimus, everolimus, and deforolimus. The mammalian target of rapamycin(mTOR)and its molecular pathways are supposed to be activated frequently in human renal cell carcinoma as well as other cancers. It has a kinase activity for 40S ribosomal protein kinase and eukaryotic translation initiation factor 4E-binding protein 1. These proteins, when phosphorylated, promote protein translation and RNA transcription in the nutrient-rich condition. mTOR inhibitors such as Temsirolimus (CCI779) and Everolimus (RAD001) are effective for suppressing cell growth with inhibiting mTOR kinase activity. Rapamycin and its related analogs such as Temsirolimus and Everolimus are less toxic for humans compared with other anti-VEGFR inhibitors and has been used as an immunosuppressive agent. These agents have an inhibitory activity against the mTORC1 complex. Since they do not have inhibitory activity against mTORC2 complex, the ability of mTOR inhibition by Temsirolimus is supposed to be 40 to 50% of full inhibition in mTOR kinase. Temsirolimus has modest anticancer activity against advanced clinical RCC patients with poor risk. The objective response rate was only 7%, 26% of patients experienced minor responses and another 17% of patients had stable disease that lasted 6 months. The median time to tumor progression and median survival for the study patients were 5.8 and 15.0 months, respectively. The overall survival of patients treated with Temsirolimus alone was statistically longer than in those treated with IFN alone in the 626 cases in phase II study. Combinations of mTOR with other anti- VEGFR agents were not effective. Vertical therapies of mTOR inhibitor in combination with AKT inhibitors, or newly development of stronger mTOR kinase which can suppress both mTORC1 and mTORC2 are planned at present. Mammalian target of rapamycin (mTOR) is a key protein kinase controlling signal transduction from various growth factors and upstream proteins to the level of mRNA translation and ribosome biogenesis, with pivotal regulatory effects on cell cycle progression, cellular proliferation and growth, autophagy and angiogenesis. The mTOR pathway, and its upstream regulators in the PI3K/PTEN/AKT cascade, are altered in a variety of experimental and human maligcies.This has led to the prediction that mTOR inhibitors may be used as anticancer agents. With the recent approval of two mTOR-targeted drugs (temsirolimus and everolimus) for the treatment of renal cell carcinoma and mantle cell lymphoma, this paradigm has been effectively translated into the clinical setting. In this review, we discuss mTOR biology and regulation, the mode of action of mTOR inhibitors as anti-cancer agents, and current clinical evidence supporting the use of rapamycin-like mTOR inhibitors in cancer treatment. Sorafenib and sunitinib are inhibitors of receptor protein tyrosine kinases (TKIs) and are approved for the treatment of metastatic renal cell carcinoma (mRCC). Although the mTOR inhibitor everolimus is effective for the treatment of patients who have failed TKI therapy, it is important to consider all available treatment options before switching therapy mode of action. Herein, we report outcomes in patients with mRCC switched to sorafenib following disease progression on sunitinib treatment. The medical records of 35 patients treated between November 2006 and November 2009 at two large referral centers in Greece were retrospectively analyzed for time-to-progression (TTP), overall survival (OS), and tolerability of sorafenib after sunitinib. Median TTP and OS on sorafenib were 4.9 and 11.5 months, respectively. Among 33 patients evaluable for tumor response, three had a partial response and 17 achieved disease stabilization (objective response rate 8.5%; total clinical benefit rate 57%). Sorafenib was well tolerated, with mostly grade 1/2 adverse events and no treatment-related deaths. Sorafenib was effective and well tolerated in this group of patients. The TTP with sorafenib following sunitinib was comparable to outcomes reported previously, providing further support that TKIs should be used in sequence before switching to an mTOR inhibitor. AIM: To describe drugs used in renal cell carcinoma. METHOD: Pubmed search for efficacy, mode of action and side effects for each molecule. Additional data were searched from the French regulatory agencies websites (HAS and ANSM). RESULTS: Since 2007, a total of three different therapeutic classes in the management of metastatic renal cell carcinoma are available. These three classes are tyrosine kinase inhibitors with sunitinib and sorafenib, the anti-VEGF antibodies (bevacizumab which is associated with alpha interferon in the treatment of advanced kidney cancer) and mTOR inhibitors with temsirolimus and everolimus. These targeted therapies are a major progress in the treatment of patients with metastatic kidney cancer. The side effects encountered with these molecules are numerous but serious side effects are less than 5% of all reported side effects. CONCLUSIONS: A better understanding of molecular mechanisms has enabled the development of new therapies for the treatment of metastatic renal cell carcinoma. In the future, a personalized approach taking into account the biology of each tumor could be created to provide a more targeted treatment.
Have Quantitative Trait Loci affecting splicing (splicing QTLs) been linked to disease?
Yes, mutations in the DNA that affect the splicing pattern of genes have been linked in transcriptome population studies to a number of diseases.
BACKGROUND: To elucidate mechanisms involved in multiple sclerosis (MS), we studied genetic regulation of experimental autoimmune encephalomyelitis (EAE) in rats, assuming a conservation of pathogenic pathways. In this study, we focused on Eae23, originally identified to regulate EAE in a (LEW.1AV1xPVG.1AV1)F2 cross. Our aim was to determine whether one or more genes within the 67 Mb region regulate EAE and to define candidate risk genes. METHODOLOGY/PRINCIPAL FINDINGS: We used high resolution quantitative trait loci (QTL) analysis in the 10th generation (G10) of an advanced intercross line (AIL) to resolve Eae23 into two QTLs that independently regulate EAE, namely Eae23a and Eae23b. We established a congenic strain to validate the effect of this region on disease. PVG alleles in Eae23 resulted in significant protection from EAE and attenuated CNS inflammation/demyelination. Disease amelioration was accompanied with increased levels of Foxp3(+) cells in the CNS of the congenic strain compared to DA. We then focused on candidate gene investigation in Eae23b, a 9 Mb region linked to all clinical phenotypes. Affymetrix exon arrays were used to study expression of the genes in Eae23b in the parental strains, where none showed differential expression. However, we found lower expression of exon 4 of ZEB1, which is specific for splice-variant Zfhep1. ZEB1 is an interleukin 2 (IL2) repressor involved in T cell development. The splice-specific variance prompted us to next analyze the expression of ZEB1 and its two splice variants, Zfhep1 and Zfhep2, in both lymph node and spleen. We demonstrated that ZEB1 splice-variants are differentially expressed; severity of EAE and higher IL2 levels were associated with down-regulation of Zfhep1 and up-regulation of Zfhep2. CONCLUSIONS/SIGNIFICANCE: We speculate that the balance between splice-variants of ZEB1 could influence the regulation of EAE. Further functional studies of ZEB1 and the splice-variants may unravel novel pathways contributing to MS pathogenesis and inflammation in general. The spontaneously hypertensive rat (SHR) is a widely used rodent model of hypertension and metabolic syndrome. Previously we identified thousands of cis-regulated expression quantitative trait loci (eQTLs) across multiple tissues using a panel of rat recombit inbred (RI) strains derived from Brown Norway and SHR progenitors. These cis-eQTLs represent potential susceptibility loci underlying physiological and pathophysiological traits manifested in SHR. We have prioritized 60 cis-eQTLs and confirmed differential expression between the parental strains by quantitative PCR in 43 (72%) of the eQTL transcripts. Quantitative trait transcript (QTT) analysis in the RI strains showed highly significant correlation between cis-eQTL transcript abundance and clinically relevant traits such as systolic blood pressure and blood glucose, with the physical location of a subset of the cis-eQTLs colocalizing with "physiological" QTLs (pQTLs) for these same traits. These colocalizing correlated cis-eQTLs (c3-eQTLs) are highly attractive as primary susceptibility loci for the colocalizing pQTLs. Furthermore, sequence analysis of the c3-eQTL genes identified single nucleotide polymorphisms (SNPs) that are predicted to affect transcription factor binding affinity, splicing and protein function. These SNPs, which potentially alter transcript abundance and stability, represent strong candidate factors underlying not just eQTL expression phenotypes, but also the correlated metabolic and physiological traits. In conclusion, by integration of genomic sequence, eQTL and QTT datasets we have identified several genes that are strong positional candidates for pathophysiological traits observed in the SHR strain. These findings provide a basis for the functional testing and ultimate elucidation of the molecular basis of these metabolic and cardiovascular phenotypes.
Which technique is used for detection of EWS/FLI1 fusion transcripts?
Molecular detection of EWS-FLI1 chimeric transcripts in Ewing family tumors is carried out by reverse transcription-polymerase chain reaction (RT-PCR).
The t(11.22)(q24.q12) results in expression of a chimeric RNA product, EWS-FLI1. This RNA product is expressed in over 85% of tumours belonging to the Ewing's family, and is increasingly used as a definitive characteristic of these tumours. In this study, we evaluated reverse transcriptase-polymerase chain (RT-PCR) for EWS-FLI1 fusion transcripts in 18 neurally derived small round cell tumours. These included six Ewing's family tumours and 12 neuroblastomas. EWS-FLI1 fusion transcripts were identified in all six Ewing's tumours, but also in two of the 12 neuroblastomas. One neuroblastoma contained the classic type 1 fusion transcript, and the second a type 1 transcript containing a 66 bp (base pair) insert that was not derived from the EWS or FLI1 gene. The presence of EWS-FLI1 fusion products in RNA extracted from primary neuroblastoma suggests the identification of EWS-FLI1 fusion transcripts is not pathognomonic for tumours of the Ewing's family. The clinical significance of these fusion transcripts in neuroblastoma is not known. Chromosomal translocations generating unique chimeric genes are highly characteristic of specific sarcomas, and their use as diagnostic markers has been suggested. From a diagnostic pathologic point of view, detection of such cytogenetic or molecular aberrations applicable to routinely processed archival tissue specimens is considered a powerful tool for tumor diagnosis. To assess the feasibility and reliability of the molecular detection of the transcript originating from the chimeric gene in paraffin-embedded tumor specimens, we performed a nested reverse transcription-polymerase chain reaction (RT-PCR)-based assay to detect the EWS-FLI1 chimeric message in a series of Ewing family tumors. Of 24 paraffin-embedded tumor specimens from 23 cases analyzed, the chimeric message was detectable in 20 (83%) specimens from 20 cases (87%) by this nested RT-PCR assay, whereas none of 7 small round cell tumors not from this family (3 alveolar rhabdomyosarcomas, 2 neuroblastomas, 2 maligt lymphomas) showed detectable chimeric messages. In the sequence analysis of the PCR products, the amplified chimeric messages contained the junctions between exon 7 of the EWS gene and any one of exons 5, 6 and 8 of the FLI1 gene. The detection process was usually completed within 3 days, except for the subseqent sequence analysis. Our results endorse the use of this molecular assay as an ancillary technique in the diagnosis of Ewing family tumors using paraffin-embedded material. OBJECTIVE: To investigate the expression of EWS-FLI1/ERG fusion transcript resulting from t(11;12)(q24;12) in paraffin-embedded tissues and its diagnostic implication for Ewing's sarcoma/peripheral primitive neuroectodermal tumors (ES/pPNET). METHODS: One-step reverse transcriptase-polymerase chain reaction (RT-PCR) was employed to detect a characteristic EWS-FLI1/ERG fusion transcript in 25 cases of ES/pPNET and 15 cases of other small round cell tumors (including 8 cases of rhabdomyosarcoma, 4 cases of synovial sarcoma, 2 cases of neuroblastoma and 1 case of lymphoma) using formalin-fixed and paraffin-embedded tissues. RESULTS: EWS-FLI1/ERG fusion transcript was detected in 20 of the 25 ES/pPNET cases (80%). The 15 non-ES/pPNET control cases were negative for EWS-FLI1/ERG fusion transcript. CONCLUSIONS: Detection of EWS-FLI1/ERG fusion transcript is a reliable index for molecular diagnosis of ES/pPNET. One-step RT-PCR is a practical method for such analysis in routine paraffin-embedded tumor tissues. BACKGROUND: Ewing's sarcoma/peripheral primitive neuroectodermal tumor (ES/pPNET) is often difficult to distinguish from other small round cell tumors. The EWS-Ets gene fusions that result from chromosomal translocations in this tumor provide potential molecular diagnostic markers. To apply these molecular markers to commonly available archival materials, we evaluated the feasibility of detecting EWS-Ets including EWS-Fli1 and EWS-ERG fusion transcripts in paraffin-embedded tissues and its diagnostic value for detecting ES/pPNET. METHODS: Thirteen paraffin-embedded samples of ES/pPNETs were retrieved from archives. Thirteen cases of other tumors with small round cell features (including rhabdomyosarcoma, neuroblastoma, lymphoma, small cell carcinoma, and desmoplastic small round cell tumor) were used as negative controls. Beta-actin and beta2-microglobulin were used as internal controls. A nested reverse transcriptase-polymerase chain reaction (RT-PCR)-based assay was performed to detect the EWS-Fli1 and EWS-ERG fusion transcripts. RESULTS: Beta-actin and beta2-microglobulin were detected in 10/13 and 13/13 ES/pPNETs, respectively. EWS-Fli1 fusion transcripts were detected in 11 of 13 (85%) ES/pPNETs. Three chimeric transcripts, all EWS-Fli1, were detected in ES/pPNET samples. Among 11 EWS-Fli1-positive cases, 7 cases had a type I fusion transcript involving fusion of EWS exon 7 with Fli1 exon 6, 2 cases had a type II fusion transcript involving EWS exon 7 with Fli1 exon 5, and 2 cases expressed fusion transcripts involving EWS exon 7 and Fli1 exon 8. Type I EWS-Fli1 fusion predominated over other types. Fusion types could not be distinguished in the remaining 2 cases. Thirteen negative controls did not show detectable chimeric messages. There was a significant relationship between EWS-Fli1 fusion transcripts and CD99 expression. CONCLUSIONS: Molecular detection of EWS-Fli1 fusion transcripts in formalin-fixed paraffin-embedded material by nested RT-PCR is feasible and is useful for the diagnosis and differential diagnosis of ES/pPNETs. We evaluated the feasibility and usefulness of reverse transcriptase-polymerase chain reaction (RT-PCR) on fine-needle aspirates for categorization of small blue round cell tumors (SBRCTs). A total of 51 cases, including 25 Ewing sarcoma/peripheral primitive neuroectodermal tumors (PNETs), 11 rhabdomyosarcomas, 13 neuroblastomas, and 2 desmoplastic small round cell tumors (DSRCTs) were analyzed. The detection of the EWS-FLI1 (20/25) and EWS-ERG (4/25) fusion transcripts resolved 24 of 25 cases of Ewing sarcoma/PNET. The PAX3/7-FKHR fusion transcript was detected in 2 of 4 cases of alveolar rhabdomyosarcoma and the EWS-WT1 transcript in both cases of DSRCT. Tyrosine hydroxylase and 3,4-dihydroxyphenylalanine (dopa) decarboxylase transcripts were demonstrated in 10 of 13 cases of neuroblastoma. In comparison, immunocytochemical analysis resolved 19 (76%) of 25 Ewing sarcomas, 9 (82%) of 11 rhabdomyosarcomas, 6 (46%) of 13 neuroblastomas, and 1 (50%) of 2 DSRCTs. Overall, RT-PCR resolved 38 (86%) of 44 vs 35 (69%) of 51 cases by immunocytochemical analysis. RT-PCR is easily applied to fine-needle aspirates of SBRCT and greatly facilitates accurate tumor typing. We report the case of a patient in whom the diagnosis of Ewing sarcoma arising from a soft tissue was made after successful treatment of diffuse large B-cell lymphoma. A 65-year-old woman presented with a rapidly growing mass in her left scapular region 8 years after successful chemotherapy with the cyclophosphamide, hydroxydaunomycin hydrochloride, vincristine, prednisolone regimen for diffuse large B-cell lymphoma. Computed tomographic examination and magnetic resoce imaging of the thorax revealed an intramuscular tumour measuring 40 mm in size in the left scapular region. Histopathological examination of an open biopsy specimen revealed a small round cell tumour that showed positive staining for CD99. Fluorescence in situ hybridization showed a split signal by a break-apart probe for the EWS gene in chromosome 22q12. Reverse transcriptase-polymerase chain reaction confirmed the expression of EWS-FLI1 fusion transcripts. Based on these findings, the patient was diagnosed as having secondary Ewing sarcoma. Despite adjuvant chemotherapy, however, she died of pulmonary metastases 2 years after the diagnosis of Ewing sarcoma. Therapy-related haematological maligcies with balanced translocations have been reported previously. A mechanism similar to that underlying the development of secondary maligcy might explain the occurrence of this solid cancer. Over the years, a wide clinicopathological spectrum has been identified within Ewing family of tumors (EFTs). As these tumors are chemosensitive, their correct and timely identification is necessary. The aims of this study were (1) to present the diverse clinicopathological and molecular profile of EFTs in our settings, (2) to identify a pragmatic approach for diagnosing EFTs, especially for application of ancillary techniques, namely RT-PCR for specific transcripts (EWS-FLI1, EWS-ERG) and FISH for EWSR1 gene rearrangement, in certain cases and (3) to show the utility of tissue microarray in establishing a new FISH test. Fifty-eight EFTs were identified in 38 males and 20 females within an age-range of 1-65 years (median, 16), mostly in lower extremities (14) (24.1 %). Therapeutically, most patients underwent neoadjuvant chemotherapy with subsequent surgery. Histopathologically, diagnosis of EFTs was initially offered in 41/58 (70.6 %) tumors. On review, 59 % tumors showed diffuse pattern, while 41 % displayed rosettes. Immunohistochemically, tumor cells were mostly diffusely positive for CD99 (48/52) (92.3 %); FLI-1 (17/18) (94.4 %); variably for BCL2 (16/18) (88.8 %), synaptophysin (6/20) (35 %), S100-P (2/7) (28.5 %), CD56 (2/5) (40 %), NSE (2/5) (40 %), calponin (3/4) (75 %), EMA (5/24) (20.8 %) and CK (3/24) (12.5 %), the latter two mostly focally. Fifty five tumors were EWS-FLI1 positive, while a single tumor was EWS-ERG positive. Sensitivity for PCR was 61 %. EWSR1 rearrangement was detected by FISH in 12/13 Ewing sarcomas/PNETs. Sensitivity for EWSR1 test was 92.3 % and specificity was 100 %. Thirty-eight tumors, including 14 molecular confirmed EFTs and 21 other tumors were tested for EWSR1 rearrangement. Among 21 unrelated tumors, EWSR1 rearrangement was detected in few myoepithelial tumors, occasional desmoplastic small round cell tumor and an extraskeletal myxoid chondrosarcoma. Further, a tissue microarray with a separate set of 8 EFTs, confirmed at another laboratory was analysed for validation of EWSR1 rearrangement test. 23/28 (82.1 %) tissue cores of the tissue microarray, stained by FISH were interpretable, including EWSR1 rearrangement, detected in 20/28 tissue cores; not detected in 3 liver cores and uninterpretable in 5 (17.8 %) cores. Classical EFTs can be diagnosed with diffuse, membranous CD99 positivity, intranuclear FLI1 positivity and LCA negativity in maligt round cells. In unconventional cases, it is indispensable to reveal the concomitant fusion m-RNA by RT-PCR. In case of negative molecular results, it is necessary to prove EWSR1 rearrangement by FISH. These tests should be interpreted with clinicopathological correlation. Tissue microarrays for FISH are useful during validation of a new test, especially when sarcomas like EFTs show less genetic heterogeneity within tumor cells.
Does the CTCF protein co-localize with cohesin?
Recent genome-wide studies mapping the binding sites of CTCF and its interacting partner, cohesin, using chromatin immunoprecipitation coupled with deep sequencing (ChIP-seq) revealded that CTCF globally co-localizes with cohesin.
Cohesin is required to prevent premature dissociation of sister chromatids after DNA replication. Although its role in chromatid cohesion is well established, the functional significance of cohesin's association with interphase chromatin is not clear. Using a quantitative proteomics approach, we show that the STAG1 (Scc3/SA1) subunit of cohesin interacts with the CCTC-binding factor CTCF bound to the c-myc insulator element. Both allele-specific binding of CTCF and Scc3/SA1 at the imprinted IGF2/H19 gene locus and our analyses of human DM1 alleles containing base substitutions at CTCF-binding motifs indicate that cohesin recruitment to chromosomal sites depends on the presence of CTCF. A large-scale genomic survey using ChIP-Chip demonstrates that Scc3/SA1 binding strongly correlates with the CTCF-binding site distribution in chromosomal arms. However, some chromosomal sites interact exclusively with CTCF, whereas others interact with Scc3/SA1 only. Furthermore, immunofluorescence microscopy and ChIP-Chip experiments demonstrate that CTCF associates with both centromeres and chromosomal arms during metaphase. These results link cohesin to gene regulatory functions and suggest an essential role for CTCF during sister chromatid cohesion. These results have implications for the functional role of cohesin subunits in the pathogenesis of Cornelia de Lange syndrome and Roberts syndromes. The cohesin complex is best known for its role in sister chromatid cohesion. Over the past few years, it has become apparent that cohesin also regulates gene expression, but the mechanisms by which it does so are unknown. Recently, three groups mapped numerous cohesin-binding sites in mammalian chromosomes and found substantial overlap with the CCCTC-binding factor (CTCF).1-3 CTCF is an insulator protein that blocks enhancer-promoter interactions, and the investigators found that cohesin also contributes to this activity. Thus, these studies demonstrate at least one mechanism by which cohesin can control gene expression. The human interleukin-3 (IL-3) and granulocyte-macrophage colony-stimulating-factor (GM-CSF, or CSF2) gene cluster arose by duplication of an ancestral gene. Although just 10 kb apart and responsive to the same signals, the IL-3 and GM-CSF genes are nevertheless regulated independently by separate, tissue-specific enhancers. To understand the differential regulation of the IL-3 and GM-CSF genes we have investigated a cluster of three ubiquitous DNase I-hypersensitive sites (DHSs) located between the two genes. We found that each site contains a conserved CTCF consensus sequence, binds CTCF, and recruits the cohesin subunit Rad21 in vivo. The positioning of these sites relative to the IL-3 and GM-CSF genes and their respective enhancers is conserved between human and mouse, suggesting a functional role in the organization of the locus. We found that these sites effectively block functional interactions between the GM-CSF enhancer and either the IL-3 or the GM-CSF promoter in reporter gene assays. These data argue that the regulation of the IL-3 and the GM-CSF promoters depends on the positions of their enhancers relative to the conserved CTCF/cohesin-binding sites. We suggest that one important role of these sites is to enable the independent regulation of the IL-3 and GM-CSF genes. Cohesin is a DNA-binding protein complex that is essential for sister chromatid cohesion and facilitates the repair of damaged DNA. In addition, cohesin has important roles in regulating gene expression, but the molecular mechanisms of this function are poorly understood. Recent experiments have revealed that cohesin binds to the same sites in mammalian genomes as the zinc finger transcription factor CTCF. At a few loci CTCF has been shown to function as an enhancer-blocking transcriptional insulator, and recent observations indicate that this function depends on cohesin. Here we review what is known about the roles of cohesin and CTCF in regulating gene expression in mammalian cells, and we discuss how cohesin might mediate the insulator function of CTCF. CTCF sites are abundant in the genomes of diverse species but their function is enigmatic. We used chromosome conformation capture to determine long-range interactions among CTCF/cohesin sites over 2 Mb on human chromosome 11 encompassing the beta-globin locus and flanking olfactory receptor genes. Although CTCF occupies these sites in both erythroid K562 cells and fibroblast 293T cells, the long-range interaction frequencies among the sites are highly cell type specific, revealing a more densely clustered organization in the absence of globin gene activity. Both CTCF and cohesins are required for the cell-type-specific chromatin conformation. Furthermore, loss of the organizational loops in K562 cells through reduction of CTCF with shRNA results in acquisition of repressive histone marks in the globin locus and reduces globin gene expression whereas silent flanking olfactory receptor genes are unaffected. These results support a genome-wide role for CTCF/cohesin sites through loop formation that both influences transcription and contributes to cell-type-specific chromatin organization and function. The cohesin protein complex holds sister chromatids in dividing cells together and is essential for chromosome segregation. Recently, cohesin has been implicated in mediating transcriptional insulation, via its interactions with CTCF. Here, we show in different cell types that cohesin functionally behaves as a tissue-specific transcriptional regulator, independent of CTCF binding. By performing matched genome-wide binding assays (ChIP-seq) in human breast cancer cells (MCF-7), we discovered thousands of genomic sites that share cohesin and estrogen receptor alpha (ER) yet lack CTCF binding. By use of human hepatocellular carcinoma cells (HepG2), we found that liver-specific transcription factors colocalize with cohesin independently of CTCF at liver-specific targets that are distinct from those found in breast cancer cells. Furthermore, estrogen-regulated genes are preferentially bound by both ER and cohesin, and functionally, the silencing of cohesin caused aberrant re-entry of breast cancer cells into cell cycle after hormone treatment. We combined chromosomal interaction data in MCF-7 cells with our cohesin binding data to show that cohesin is highly enriched at ER-bound regions that capture inter-chromosomal loop anchors. Together, our data show that cohesin cobinds across the genome with transcription factors independently of CTCF, plays a functional role in estrogen-regulated transcription, and may help to mediate tissue-specific transcriptional responses via long-range chromosomal interactions. Cellular metabolism alters patterns of gene expression through a variety of mechanisms, including alterations in histone modifications and transcription factor activity. Nicotinamide adenine dinucleotide (NAD)-dependent proteins such as poly(ADP ribose) polymerases (PARPs) and sirtuin deacetylases play important roles in this regulation, thus NAD provides a crucial link between metabolism and these cellular signaling processes. Here, we found that lowering NAD levels in mouse primary cortical neurons led to decreased activity-dependent BDNF expression. The altered BDNF transcription occurred independently of Sirt or Parp activities; instead, low NAD levels promoted increased DNA methylation of the activity-dependent BDNF promoter. Increased methylation at this promoter triggered the dissociation of the insulator protein CTCF as well as the accompanying cohesin from the BDNF locus. The loss of these proteins resulted in histone acetylation and methylation changes at this locus consistent with chromatin compaction and gene silencing. Because BDNF is critical for neuronal function, these results suggest that age- or nutrition-associated declines in NAD levels as well as deficits in cohesin function associated with disease modulate BDNF expression and could contribute to cognitive impairment. Recent studies have shown that the protein CTCF, which plays an important role in insulation and in large-scale organization of chromatin within the eukaryotic nucleus, depends for both activities on recruitment of the cohesin complex. We show here that the interaction of CTCF with the cohesin complex involves direct contacts between the cohesin subunit SA2 and specific regions of the C-terminal tail of CTCF. All other cohesin components are recruited through their interaction with SA2. Expression in vivo of CTCF mutants lacking the C-terminal domain, or with mutations at sites within it required for SA2 binding, disrupts the normal expression profile of the imprinted genes IGF2-H19 and also results in a loss of insulation activity. Taken together, our results demonstrate that specific sites on the C terminus of CTCF are essential for cohesin binding and insulator function. The only direct interaction between CTCF and cohesin involves contact with SA2, which is external to the cohesin ring. This suggests that in recruiting cohesin to CTCF, SA2 could bind first and the ring could assemble subsequently. The cohesin complex holds sister chromatids together and is essential for chromosome segregation. Recently, cohesins have been implicated in transcriptional regulation and insulation through genome-wide colocalization with the insulator protein CTCF, including involvement at the imprinted H19/Igf2 locus. CTCF binds to multiple imprinted loci and is required for proper imprinted expression at the H19/Igf2 locus. Here we report that cohesins colocalize with CTCF at two additional imprinted loci, the Dlk1-Dio3 and the Kcnq1/Kcnq1ot1 loci. Similar to the H19/Igf2 locus, CTCF and cohesins preferentially bind to the Gtl2 differentially methylated region (DMR) on the unmethylated maternal allele. To determine the functional importance of the binding of CTCF and cohesins at the three imprinted loci, CTCF and cohesins were depleted in mouse embryonic fibroblast cells. The monoallelic expression of imprinted genes at these three loci was maintained. However, mRNA levels for these genes were typically increased; for H19 and Igf2 the increased level of expression was independent of the CTCF-binding sites in the imprinting control region. Results of these experiments demonstrate an unappreciated role for CTCF and cohesins in the repression of imprinted genes in somatic cells. CCCTC-binding factor (CTCF) is a master organizer of genome spatial organization and plays an important role in mediating extensive chromatin interactions. Circular chromosome conformation capture (4C) is a high-throughput approach that allows genome-wide screening for unknown potential interaction partners. Using a conserved CTCF binding site on the Bcl11b locus as bait, an interaction partner at the Arhgap6 locus on a different chromosome was identified by 4C. Additional experiments verified that the interchromatin interaction between the Bcl11b and Arhgap6 loci was cell-type specific, which was cooperatively mediated by CTCF and cohesin. Functional analysis showed that the interchromatin interaction partners were repressing regulatory elements. These results indicate that interaction chromatin loops regulate the expression of the relevant genes. During the last decades our view of the genome organization has changed. We moved from a linear view to a looped view of the genome. It is now well established that inter- and intra-connections occur between chromosomes and play a major role in gene regulations. These interconnections are mainly orchestrated by the CTCF protein, which is also known as the "master weaver" of the genome. Recent advances in sequencing and genome-wide studies revealed that CTCF binds to DNA at thousands of sites within the human genome, providing the possibility to form thousands of genomic connection hubs. Strikingly, two histone variants, namely H2A.Z and H3.3, strongly co-localize at CTCF binding sites. In this article, we will review the recent advances in CTCF biology and discuss the role of histone variants H2A.Z and H3.3 at CTCF binding sites. The somatic recombination of lymphocyte antigen receptor loci is integral to lymphocyte differentiation and adaptive immunity. Here we review the relation of this highly choreographed process with the zinc finger protein CTCF and with cohesin, a protein complex best known for its essential functions in post-replicative DNA repair and chromosome segregation during the cell cycle. At lymphocyte antigen receptor loci, CTCF and cohesin shape long-range interactions and contribute to V(D)J recombination by facilitating lineage- and developmental-stage-specific transcription and accessibility. Extraordinary single-cell diversity is generated in the vertebrate nervous system by the combinatorial expression of the clustered protocadherin genes (Pcdhα, -β, and -γ). This diversity is generated by a combination of stochastic promoter choice and alternative pre-mRNA splicing. Here we show that both the insulator-binding protein CTCF and the cohesin complex subunit Rad21 bind to two highly conserved DNA sequences, the first within and the second downstream of transcriptionally active Pcdhα promoters. Both CTCF and Rad21 bind to these sites in vitro and in vivo, this binding directly correlates with alternative isoform expression, and knocking down CTCF expression reduces alternative isoform expression. Remarkably, a similarly spaced pair of CTCF/Rad21 binding sites was identified within a distant enhancer element (HS5-1), which is required for normal levels of alternative isoform expression. We also identify an additional, unique regulatory role for cohesin, as Rad21 binds to another enhancer (HS7) independently of CTCF, and knockdown of Rad21 reduces expression of the constitutive, biallelically expressed Pcdhα isoforms αc1 and αc2. We propose that CTCF and the cohesin complex initiate and maintain Pcdhα promoter choice by mediating interactions between Pcdhα promoters and enhancers. Eukaryotic genomes are organized into higher order chromatin architectures by protein-mediated long-range interactions in the nucleus. CCCTC-binding factor (CTCF), a sequence-specific transcription factor, serves as a chromatin organizer in building this complex chromatin structure by linking chromosomal domains. Recent genome-wide studies mapping the binding sites of CTCF and its interacting partner, cohesin, using chromatin immunoprecipitation coupled with deep sequencing (ChIP-seq) revealded that CTCF globally co-localizes with cohesin. This partnership between CTCF and cohesin is emerging as a novel and perhaps pivotal aspect of gene regulatory mechanisms, in addition to playing a role in the organization of higher order chromatin architecture. The contribution of human subtelomeric DNA and chromatin organization to telomere integrity and chromosome end protection is not yet understood in molecular detail. Here, we show by ChIP-Seq that most human subtelomeres contain a CTCF- and cohesin-binding site within ∼1-2 kb of the TTAGGG repeat tract and adjacent to a CpG-islands implicated in TERRA transcription control. ChIP-Seq also revealed that RNA polymerase II (RNAPII) was enriched at sites adjacent to the CTCF sites and extending towards the telomere repeat tracts. Mutation of CTCF-binding sites in plasmid-borne promoters reduced transcriptional activity in an orientation-dependent manner. Depletion of CTCF by shRNA led to a decrease in TERRA transcription, and a loss of cohesin and RNAPII binding to the subtelomeres. Depletion of either CTCF or cohesin subunit Rad21 caused telomere-induced DNA damage foci (TIF) formation, and destabilized TRF1 and TRF2 binding to the TTAGGG proximal subtelomere DNA. These findings indicate that CTCF and cohesin are integral components of most human subtelomeres, and important for the regulation of TERRA transcription and telomere end protection. The closely linked human protocadherin (Pcdh) α, β, and γ gene clusters encode 53 distinct protein isoforms, which are expressed in a combinatorial manner to generate enormous diversity on the surface of individual neurons. This diversity is a consequence of stochastic promoter choice and alternative pre-mRNA processing. Here, we show that Pcdhα promoter choice is achieved by DNA looping between two downstream transcriptional enhancers and individual promoters driving the expression of alternate Pcdhα isoforms. In addition, we show that this DNA looping requires specific binding of the CTCF/cohesin complex to two symmetrically aligned binding sites in both the transcriptionally active promoters and in one of the enhancers. These findings have important implications regarding enhancer/promoter interactions in the generation of complex Pcdh cell surface codes for the establishment of neuronal identity and self-avoidance in individual neurons. Current epigenomics approaches have facilitated the genome-wide identification of regulatory elements based on chromatin features and transcriptional regulator binding and have begun to map long-range interactions between regulatory elements and their targets. Here, we focus on the emerging roles of CTCF and the cohesin in coordinating long-range interactions between regulatory elements. We discuss how species-specific transposable elements may influence such interactions by remodeling the CTCF binding repertoire and suggest that cohesin's association with enhancers, promoters, and sites defined by CTCF binding has the potential to form developmentally regulated networks of long-range interactions that reflect and promote cell-type-specific transcriptional programs. DNA binding factors are essential for regulating gene expression. CTCF and cohesin are DNA binding factors with central roles in chromatin organization and gene expression. We determined the sites of CTCF and cohesin binding to DNA in mouse brain, genome wide and in an allele-specific manner with high read-depth ChIP-seq. By comparing our results with existing data for mouse liver and embryonic stem (ES) cells, we investigated the tissue specificity of CTCF binding sites. ES cells have fewer unique CTCF binding sites occupied than liver and brain, consistent with a ground-state pattern of CTCF binding that is elaborated during differentiation. CTCF binding sites without the canonical consensus motif were highly tissue specific. In brain, a third of CTCF and cohesin binding sites coincide, consistent with the potential for many interactions between cohesin and CTCF but also many instances of independent action. In the context of genomic imprinting, CTCF and/or cohesin bind to a majority but not all differentially methylated regions, with preferential binding to the unmethylated parental allele. Whether the parental allele-specific methylation was established in the parental germlines or post-fertilization in the embryo is not a determit in CTCF or cohesin binding. These findings link CTCF and cohesin with the control regions of a subset of imprinted genes, supporting the notion that imprinting control is mechanistically diverse. BACKGROUND: Recent studies suggested that human/mammalian genomes are divided into large, discrete domains that are units of chromosome organization. CTCF, a CCCTC binding factor, has a diverse role in genome regulation including transcriptional regulation, chromosome-boundary insulation, DNA replication, and chromatin packaging. It remains unclear whether a subset of CTCF binding sites plays a functional role in establishing/maintaining chromatin topological domains. RESULTS: We systematically analysed the genomic, transcriptomic and epigenetic profiles of the CTCF binding sites in 56 human cell lines from ENCODE. We identified ~24,000 CTCF sites (referred to as constitutive sites) that were bound in more than 90% of the cell lines. Our analysis revealed: 1) constitutive CTCF loci were located in constitutive open chromatin and often co-localized with constitutive cohesin loci; 2) most constitutive CTCF loci were distant from transcription start sites and lacked CpG islands but were enriched with the full-spectrum CTCF motifs: a recently reported 33/34-mer and two other potentially novel (22/26-mer); 3) more importantly, most constitutive CTCF loci were present in CTCF-mediated chromatin interactions detected by ChIA-PET and these pair-wise interactions occurred predomitly within, but not between, topological domains identified by Hi-C. CONCLUSIONS: Our results suggest that the constitutive CTCF sites may play a role in organizing/maintaining the recently identified topological domains that are common across most human cells. The chromatin regulatory factors CTCF and cohesin have been implicated in the coordinated control of multiple gene loci in Epstein-Barr virus (EBV) latency. We have found that CTCF and cohesin are highly enriched at the convergent and partially overlapping transcripts for the LMP1 and LMP2A genes, but it is not yet known how CTCF and cohesin may coordinately regulate these transcripts. We now show that genetic disruption of this CTCF binding site (EBVΔCTCF166) leads to a deregulation of LMP1, LMP2A, and LMP2B transcription in EBV-immortalized B lymphocytes. EBVΔCTCF166 virus-immortalized primary B lymphocytes showed a decrease in LMP1 and LMP2A mRNA and a corresponding increase in LMP2B mRNA. The reduction of LMP1 and LMP2A correlated with a loss of euchromatic histone modification H3K9ac and a corresponding increase in heterochromatic histone modification H3K9me3 at the LMP2A promoter region in EBVΔCTCF166. Chromosome conformation capture (3C) revealed that DNA loop formation with the origin of plasmid replication (OriP) enhancer was eliminated in EBVΔCTCF166. We also observed that the EBV episome copy number was elevated in EBVΔCTCF166 and that this was not due to increased lytic cycle activity. These findings suggest that a single CTCF binding site controls LMP2A and LMP1 promoter selection, chromatin boundary function, DNA loop formation, and episome copy number control during EBV latency. Runx1 is a transcription factor essential for definitive hematopoiesis. In all vertebrates, the Runx1 gene is transcribed from two promoters: a proximal promoter (P2), and a distal promoter (P1). We previously found that runx1 expression in a specific hematopoietic cell population in zebrafish embryos depends on cohesin. Here we show that zebrafish runx1 is directly bound by cohesin and CCCTC binding factor (CTCF) at the P1 and P2 promoters, and within the intron between P1 and P2. Cohesin initiates expression of runx1 in the posterior lateral mesoderm and influences promoter use, while CTCF represses its expression in the newly emerging cells of the tail bud. The intronic binding sites for cohesin and CTCF coincide with histone modifications that confer enhancer-like properties, and two of the cohesin/CTCF sites behaved as insulators in an in vivo assay. The identified cohesin and CTCF binding sites are likely to be cis-regulatory elements (CREs) for runx1 since they also recruit RNA polymerase II (RNAPII). CTCF depletion excluded RNAPII from two intronic CREs but not the promoters of runx1. We propose that cohesin and CTCF have distinct functions in the regulation of runx1 during zebrafish embryogenesis, and that these regulatory functions are likely to involve runx1 intronic CREs. Cohesin (but not CTCF) depletion enhanced RUNX1 expression in a human leukemia cell line, suggesting conservation of RUNX1 regulation through evolution.
What is the application of the Bimolecular Fluorescence Complementation (BiFC) assay in Drosophila embryos?
Bimolecular fluorescence complementation (BiFC) is a powerful method for studying protein-protein interactions in different cell types and organisms. This method was recently developed in the fruit fly Drosophila melanogaster, allowing analyzing protein interaction properties in a physiologically relevant developing context.
Protein-protein interactions play a pivotal role in coordinating many cellular processes. Determination of subcellular localization of interacting proteins and visualization of dynamic interactions in living cells are crucial to elucidate cellular functions of proteins. Using fluorescent proteins, we previously developed a bimolecular fluorescence complementation (BiFC) assay and a multicolor BiFC assay to visualize protein-protein interactions in living cells. However, the sensitivity of chromophore maturation of enhanced yellow fluorescent protein (YFP) to higher temperatures requires preincubation at lower temperatures prior to visualizing the BiFC signal. This could potentially limit their applications for the study of many signaling molecules. Here we report the identification of new fluorescent protein fragments derived from Venus and Cerulean for BiFC and multicolor BiFC assays under physiological culture conditions. More importantly, the newly identified combinations exhibit a 13-fold higher BiFC efficiency than originally identified fragments derived from YFP. Furthermore, the use of new combinations reduces the amount of plasmid required for transfection and shortens the incubation time, leading to a 2-fold increase in specific BiFC signals. These newly identified fluorescent protein fragments will facilitate the study of protein-protein interactions in living cells and whole animals under physiological conditions. A variety of experimental methods have been developed for the analysis of protein interactions. The majority of these methods either require disruption of the cells to detect molecular interactions or rely on indirect detection of the protein interaction. The bimolecular fluorescence complementation (BiFC) assay provides a direct approach for the visualization of molecular interactions in living cells and organisms. The BiFC approach is based on the facilitated association between two fragments of a fluorescent protein when the fragments are brought together by an interaction between proteins fused to the fragments. The BiFC approach has been used for visualization of interactions among a variety of structurally diverse interaction partners in many different cell types. It enables detection of transient complexes as well as complexes formed by a subpopulation of the interaction partners. It is essential to include negative controls in each experiment in which the interface between the interaction partners has been mutated or deleted. The BiFC assay has been adapted for simultaneous visualization of multiple protein complexes in the same cell and the competition for shared interaction partners. A ubiquitin-mediated fluorescence complementation assay has also been developed for visualization of the covalent modification of proteins by ubiquitin family peptides. These fluorescence complementation assays have a great potential to illuminate a variety of biological interactions in the future. BACKGROUND: Protein interactions control the regulatory networks underlying developmental processes. The understanding of developmental complexity will, therefore, require the characterization of protein interactions within their proper environment. The bimolecular fluorescence complementation (BiFC) technology offers this possibility as it enables the direct visualization of protein interactions in living cells. However, its potential has rarely been applied in embryos of animal model organisms and was only performed under transient protein expression levels. RESULTS: Using a Hox protein partnership as a test case, we investigated the suitability of BiFC for the study of protein interactions in the living Drosophila embryo. Importantly, all BiFC parameters were established with constructs that were stably expressed under the control of endogenous promoters. Under these physiological conditions, we showed that BiFC is specific and sensitive enough to analyse dynamic protein interactions. We next used BiFC in a candidate interaction screen, which led to the identification of several Hox protein partners. CONCLUSION: Our results establish the general suitability of BiFC for revealing and studying protein interactions in their physiological context during the rapid course of Drosophila embryonic development.
Which pathological condition of the heart is known as hypertrophic cardiomyopathy (HCM)?
Hypertrophic cardiomyopathy (HCM) has been recently recognized as the most common inherited cardiovascular disorder, affecting 1 in 500 adults worldwide. HCM is characterized by myocyte hypertrophy resulting in thickening of the ventricular wall, myocyte disarray, interstitial and/or replacement fibrosis, decreased ventricular cavity volume and diastolic dysfunction. HCM is also the most common cause of sudden death in the young particularly among athletes. A large proportion of patients diagnosed with HCM have mutations in sarcomeric proteins. HCM is the most prevalent genetic disorder affecting the heart and is typically inherited in an autosomal dominant pattern. Adults with cardiomyopathy suffer SCD or adverse events such as stroke and heart failure from HCM.
Hypertrophic cardiomyopathy (HCM) is a clinically heterogeneous autosomal domit heart disease characterised by left ventricular hypertrophy in the absence of another cardiac or systemic disease that is capable of producing significant wall thickening. Microscopically it is characterised by cardiomyocyte hypertrophy, myofibrillar disarray and fibrosis. The phenotypic expression of HCM is multifactorial, with the majority of cases occurring secondary to mutations in genes encoding the sarcomere proteins. In conjunction with the genetic heterogeneity of HCM, phenotypic expression also exhibits a high level of variability even within families with the same aetiological mutation, and may be influenced by additional genetic factors. Polymorphisms of the renin-angiotensin-aldosterone system (RAAS) represent an attractive hypothesis as potential disease modifiers, as these genetic variants alter the 'activation status' of the RAAS, which leads to more left ventricular hypertrophy through different pathways. The main objective of this review is to provide an overview of the role of different polymorphisms identified in the RAAS, in patients with HCM. BACKGROUND: Hypertrophic cardiomyopathy (HCM) is a clinically heterogeneous genetic heart disease characterized by left ventricular hypertrophy in the absence of another disease that could explain the wall thickening. Elucidation of the genetic basis of HCM lead to the identification of several genes encoding sarcomeric proteins, such as MYH7, MYBPC3, TPM1, TNNT2, and TNNI3. Sarcomeric genes are mutated in approximately 40% of HCM patients and a possible explanation for the incomplete yield of mutation-positive HCM may be somatic mutations. METHODS AND RESULTS: We studied 104 unrelated patients with non-familial HCM. Patients underwent clinical evaluation and mutation screening of 5 genes implicated in HCM (MYH7, MYBPC3, TPM1, TNNT2, and TNNI3) in genomic DNA isolated from resected cardiac tissue; 41 of 104 were found to carry a mutation, but as several patients carried the same mutations, the total amount of different mutations was 37; 20 of these mutations have been previously described, and pathogenicity has been assessed. To determine the effect of the 17 new mutations an in silico assay was performed and it predicted that 4 variants were damaging mutations. All identified variants were also seen in the DNA isolated from the corresponding blood, which demonstrated the absence of somatic mutations. CONCLUSIONS: Somatic mutations in MYH7, MYBPC3, TPM1, TNNT2, and TNNI3 do not represent an important etiologic pathway in HCM. PURPOSE: To present an overview of clinical issues related to adults with hypertrophic cardiomyopathy (HCM), their presenting symptoms, diagnosis, physical examination findings, treatment, and follow-up care. DATA SOURCES: A comprehensive search of Medline (PubMed) and CINAHL was conducted using the key terms HCM, treatment, diagnosis, sudden cardiac death (SCD), and complications. This search yielded 21 articles used for this article. There were three reference books used for background, diagnosis, and treatment information as well. CONCLUSIONS: Although HCM is the most prevalent genetic disorder affecting the heart, it often goes undiagnosed until midlife after patients show symptoms of myocardial remodeling. Adults with cardiomyopathy suffer SCD or adverse events such as stroke and heart failure from HCM. Early diagnosis will prevent SCD, improve quality of life, and slow patient's progression to heart failure. IMPLICATIONS FOR PRACTICE: Early recognition of HCM in adults by their primary care providers will improve patients' quality of life and reduce incidence of SCD, heart failure, and stroke. Hypertrophic cardiomyopathy (HCM) is a genetic cardiomyopathy. The prevalence of phenotypic expression, in the absence of another systemic or cardiac disease causing increased left ventricular (LV) wall thickness, is estimated to be 1:500. The frequency of clinical presentation is far less, highlighting the need for a non-invasive diagnostic imaging tool. Echocardiography is readily available and allows for structural characterization and hemodynamic assessment of the hypertrophic heart and to screen patients at-risk for HCM, such as first degree relatives of affected individuals, and differentiate HCM from the athletic heart. Echocardiography can also be used to assess for anatomic abnormalities of the mitral valve apparatus that may exacerbate LV outflow track obstruction and to further risk stratify patients during exercise. Finally, echocardiography plays an integral role in guiding alcohol septal ablation procedures. Hypertrophic cardiomyopathy (HCM) has been recently recognized as the most common inherited cardiovascular disorder, affecting 1 in 500 adults worldwide. HCM is characterized by myocyte hypertrophy resulting in thickening of the ventricular wall, myocyte disarray, interstitial and/or replacement fibrosis, decreased ventricular cavity volume and diastolic dysfunction. HCM is also the most common cause of sudden death in the young. A large proportion of patients diagnosed with HCM have mutations in sarcomeric proteins. However, it is unclear how these mutations lead to the cardiac phenotype, which is variable even in patients carrying the same causal mutation. Abnormalities in calcium cycling, oxidative stress, mitochondrial dysfunction and energetic deficiency have been described constituting the basis of therapies in experimental models of HCM and HCM patients. This review focuses on evidence supporting the role of cellular metabolism and mitochondria in HCM. AIMS: Familial hypertrophic cardiomyopathy (HCM) is one the most common heart disorders, with gene mutations in the cardiac sarcomere. Studying HCM with patient-specific induced pluripotent stem-cell (iPSC)-derived cardiomyocytes (CMs) would benefit the understanding of HCM mechanism, as well as the development of personalized therapeutic strategies. METHODS AND RESULTS: To investigate the molecular mechanism underlying the abnormal CM functions in HCM, we derived iPSCs from an HCM patient with a single missense mutation (Arginine442Glycine) in the MYH7 gene. CMs were next enriched from HCM and healthy iPSCs, followed with whole transcriptome sequencing and pathway enrichment analysis. A widespread increase of genes responsible for 'Cell Proliferation' was observed in HCM iPSC-CMs when compared with control iPSC-CMs. Additionally, HCM iPSC-CMs exhibited disorganized sarcomeres and electrophysiological irregularities. Furthermore, disease phenotypes of HCM iPSC-CMs were attenuated with pharmaceutical treatments. CONCLUSION: Overall, this study explored the possible patient-specific and mutation-specific disease mechanism of HCM, and demonstrates the potential of using HCM iPSC-CMs for future development of therapeutic strategies. Additionally, the whole methodology established in this study could be utilized to study mechanisms of other human-inherited heart diseases. Hypertrophic cardiomyopathy (HCM) is the most common cause of sudden cardiac death (SCD) in the young, particularly among athletes. Identifying high risk individuals is very important for SCD prevention. The purpose of this review is to stress that noninvasive diagnostic testing is important for risk assessment. Extreme left ventricular hypertrophy and documented ventricular tachycardia and fibrillation increase the risk of SCD. Fragmented QRS and T wave inversion in multiple leads are more common in high risk patients. Cardiac magnetic resoce imaging provides complete visualization of the left ventricular chamber, allowing precise localization of the distribution of hypertrophy and measurement of wall thickness and cardiac mass. Moreover, with late gadolinium enhancement, patchy myocardial fibrosis within the area of hypertrophy can be detected, which is also helpful in risk stratification. Genetic testing is encouraged in all cases, especially in those with a family history of HCM and SCD. Familial hypertrophic cardiomyopathy (HCM), due to point mutations in genes for sarcomere proteins such as myosin, occurs in 1/500 people and is the most common cause of sudden death in young individuals. Similar mutations in skeletal muscle, e.g., in the MYH7 gene for slow myosin found in both the cardiac ventricle and slow skeletal muscle, may also cause severe disease but the severity and the morphological changes are often different. In HCM, the modified protein function leads, over years to decades, to secondary remodeling with substantial morphological changes, such as hypertrophy, myofibrillar disarray, and extensive fibrosis associated with severe functional deterioration. Despite intense studies, it is unclear how the moderate mutation-induced changes in protein function cause the long-term effects. In hypertrophy of the heart due to pressure overload (e.g., hypertension), mechanical stress in the myocyte is believed to be major initiating stimulus for activation of relevant cell signaling cascades. Here it is considered how expression of mutated proteins, such as myosin or regulatory proteins, could have similar consequences through one or both of the following mechanisms: (1) contractile instabilities within each sarcomere (with more than one stable velocity for a given load), (2) different tension generating capacities of cells in series. These mechanisms would have the potential to cause increased tension and/or stretch of certain cells during parts of the cardiac cycle. Modeling studies are used to illustrate these ideas and experimental tests are proposed. The applicability of similar ideas to skeletal muscle is also postulated, and differences between heart and skeletal muscle are discussed. Hypertrophic cardiomyopathy (HCM) is a primary disease of the cardiac muscle that occurs mainly due to mutations (>1,400 variants) in genes encoding for the cardiac sarcomere. HCM, the most common familial form of cardiomyopathy, affecting one in every 500 people in the general population, is typically inherited in an autosomal domit pattern, and presents variable expressivity and age-related penetrance. Due to the morphological and pathological heterogeneity of the disease, the appearance and progression of symptoms is not straightforward. Most HCM patients are asymptomatic, but up to 25% develop significant symptoms, including chest pain and sudden cardiac death. Sudden cardiac death is a dramatic event, since it occurs without warning and mainly in younger people, including trained athletes. Molecular diagnosis of HCM is of the outmost importance, since it may allow detection of subjects carrying mutations on HCM-associated genes before development of clinical symptoms of HCM. However, due to the genetic heterogeneity of HCM, molecular diagnosis is difficult. Currently, there are mainly four techniques used for molecular diagnosis of HCM, including Sanger sequencing, high resolution melting, mutation detection using DNA arrays, and next-generation sequencing techniques. Application of these methods has proven successful for identification of mutations on HCM-related genes. This review summarizes the features of these technologies, highlighting their strengths and weaknesses. Furthermore, current therapeutics for HCM patients are correlated with clinically observed phenotypes and are based on the alleviation of symptoms. This is mainly due to insufficient knowledge on the mechanisms involved in the onset of HCM. Tissue engineering alongside regenerative medicine coupled with otherapeutics may allow fulfillment of those gaps, together with screening of novel therapeutic drugs and target delivery systems.
What is the genetic basis of Rubinstein-Taybi syndrome?
Rubinstein-Taybi syndrome (RTS) is a rare autosomal dominant disorder (prevalence 1:125,000) characterised by broad thumbs and halluces, facial dysmorphism, psychomotor development delay, skeletal defects, abnormalities in the posterior fossa and short stature. The known genetic causes are a microdeletion at 16p13.3 or mutations or deletions of the cAMP-response element binding protein-BP (CREBBP) (50-60% of the cases) and of the homologous gene E1A-binding protein (EP300) at 22q13 (5%). Direct sequencing of CREBBP performed in 13 RSTS patients identified the three zinc fingers (CH1, CH2, CH3) and HAT domain as mutational hotspots. Thus about 55% of patients have cytogenetic or molecular abnormalities in the Crebbp or E1A binding protein p300 (Ep300) gene, leaving the diagnosis in 45% of patients to rest on clinical features only.
The Rubinstein-Taybi syndrome (RTS) is a well-defined syndrome with facial abnormalities, broad thumbs, broad big toes and mental retardation as the main clinical features. Many patients with RTS have been shown to have breakpoints in, and microdeletions of, chromosome 16p13.3 (refs 4-8). Here we report that all these breakpoints are restricted to a region that contains the gene for the human CREB binding protein (CBP), a nuclear protein participating as a co-activator in cyclic-AMP-regulated gene expression. We show that RTS results not only from gross chromosomal rearrangements of chromosome 16p, but also from point mutations in the CBP gene itself. Because the patients are heterozygous for the mutations, we propose that the loss of one functional copy of the CBP gene underlies the developmental abnormalities in RTS and possibly the propensity for maligcy. Rubinstein-Taybi syndrome (RTS) is a well-defined syndrome characterized by facial abnormalities, broad thumbs, broad big toes, and growth and mental retardation as the main clinical features. RTS was shown to be associated with disruption of the CREB-binding protein gene CBP (CREBBP), either by gross chromosomal rearrangements or by point mutations. Translocations and inversions involving chromosome band 16p13.3 form the minority of CBP mutations, whereas microdeletions occur more frequently (about 10%). Most deletion studies in RTS are performed by FISH analysis, and five cosmids must be used to cover the whole of the CBP gene, which spreads over 150 kb. Here we report the design of gene dosage assays by real-time quantitative PCR that are targeted on three exons located respectively at the 5' end (exon 2), in the middle (exon 12), and at the 3' end (exon 30) of the CBP gene. This technique proved to be efficient and powerful in finding deletions and complementary to the other available techniques, since it allowed us to identify deletions at the 3' end of the gene that had been missed by FISH analysis, and to refine some deletion breakpoints. Our results therefore suggest that real-time quantitative PCR is a useful technique to be included in the deletion search in RTS patients. We report on a six-year-old boy with typical Rubinstein-Taybi syndrome (RSTS) phenotype. Clinical findings included mental and motor retardation, patent ductus arteriosus (PDA), undescended testes, hirsutism, broad thumbs with radial angulation and broad toes, and inguinal hernia. His karyotype was normal (46, XY) and fluorescence in situ hybridization (FISH) showed no deletion of the CREBBP [cAMP response element-binding (CREB) binding protein] gene on chromosome 16p13.3. CREBBP gene sequencing also revealed normal results. We wish to present this case because this patient had typical RSTS phenotype, but normal FISH and CREBBP gene sequencing results. It could be possible that genetic heterogeneity is related with novel mutations in other genes. With the publication of such cases, their significance will be brought to the attention of researchers in this field. Rubinstein-Taybi syndrome (RTS) is a rare autosomal domit genetic disorder and is characterized by mental retardation, distinctive facial features, broad and often angulated thumbs and great toes. We report on a 7 year old boy with classical Rubinstein-Taybi syndrome. His facial and clinical features were very typical, including broad thumbs with radial angulation and broad great toes. Rigorous genetic analysis of the CREBBP and EP300 genes using DNA sequencing and multiple ligation-dependent probe amplification (MLPA) revealed no causative mutation in this boy, only a hitherto unreported but paternally inherited heterozygous sequence alteration, c.506 1+9C>T in IVS 30-31, which most likely represents a normal variant (NetGene 2 splice prediction software). We question if this boy could have a hitherto undetectable mutation type. Rubinstein-Taybi syndrome or Broad Thumb-Hallux syndrome is a genetic disorder characterized by facial dysmorphism, growth retardation, and mental deficiency. A seven-year-old girl had come to the Department of Pedodontics, Istanbul Medipol University, Faculty of Dentistry, Turkey, with a complaint of caries and bleeding of gingivae. The patient was mentally retarded. Extraoral features revealed distinctive facial appearance with a broad fore head, hypertelorism, broad nasal bridge, and beaked nose. Intraoral features observed were talons cusps in the upper lateral incisors, carious teeth, and plaque accumulation. Since the patient was mentally retarded, the dental treatment was done under GA. The treatment plan and dental management of this patient are discussed in this case report.
What is the function of the viral KP4 protein?
The virally encoded fungal toxin KP4 specifically blocks L-type voltage-gated calcium channels.
Killer toxins are polypeptides secreted by some fungal species that kill sensitive cells of the same or related species. In the best-characterized cases, they function by creating new pores in the cell membrane and disrupting ion fluxes. Immunity or resistance to the toxins is conferred by the preprotoxins (or products thereof) or by nuclear resistance genes. In several cases, the toxins are encoded by one or more genomic segments of resident double-stranded RNA viruses. The known toxins are composed of one to three polypeptides, usually present as multimers. We have further characterized the KP4 killer toxin from the maize smut fungus Ustilago maydis. This toxin is also encoded by a single viral double-stranded RNA but differs from other known killer toxins in several respects: it has no N-linked glycosylation either in the precursor or in the mature polypeptide, it is the first killer toxin demonstrated to be a single polypeptide, and it is not processed by any of the known secretory proteinases (other than the signal peptidase). It is efficiently expressed in a heterologous fungal system. Some strains of the plant-pathogenic fungus Ustilago maydis secrete toxins (killer toxins) that are lethal to susceptible strains of the same fungus. There are three well-characterized killer toxins in U. maydis-KP1, KP4, and KP6-which are secreted by the P1, P4, and P6 subtypes, respectively. These killer toxins are small polypeptides encoded by segments of an endogenous, persistent double-stranded RNA (dsRNA) virus in each U. maydis subtype. In P4 and P6, the M2 dsRNA segment encodes the toxin. In this work, the KP1 killer toxin was purified for internal amino acid sequence analysis, and P1M2 was identified as the KP1 toxin-encoding segment by sequence analysis of cDNA clones. The KP1 toxin is a monomer with a predicted molecular weight of 13.4kDa and does not have extensive sequence similarity with other viral anti-fungal toxins. The P1M2 segment is different from the P4 and P6 toxin-encoding dsRNA segments in that the 3' non-coding region of its plus strand has no sequence homology to the 3' ends of the plus strands of P1M1, P4M2, or P6M2. The cDNA encoding the antifungal protein KP4 from Ustilago maydis-infecting virus was inserted behind the ubiquitin promoter of maize and genetically transferred to wheat varieties particularly susceptible to stinking smut (Tilletia tritici) disease. The transgene was integrated and inherited over several generations. Of seven transgenic lines, three showed antifungal activity against U. maydis. The antifungal activity correlated with the presence of the KP4 transgene. KP4-transgenic, soil-grown wheat plants exhibit increased endogenous resistance against stinking smut. The viral gene for the killer protein 4 (KP4) has been explored for its antifungal effect in genetically modified wheat to defeat specifically the seed-transmitted smut and bunt diseases. In vitro both important seed-transmitted diseases of wheat, loose smut (Ustilago tritici) and stinking smut (Tilletia caries), are susceptible to KP4, whereas all other organisms tested so far proved to be not susceptible to KP4. For studies in planta we used stinking smut as a model fungus. In greenhouse experiments, two KP4-transgenic wheat lines showed up to 30% lower symptom development as compared to the nontransgenic control. As the last step in the proof of concept, field-testing has shown for the first time increased fungal resistance of a transgene in wheat. Due to its specificity against smuts and bunts, KP4 presents a very low risk to humans and the environment. Field-testing in Switzerland is regulated by a strong law, which for research is acceptable if legally and scientifically correctly applied. Plant defensins are small, highly stable, cysteine-rich antimicrobial proteins that are thought to constitute an important component of plant defense against fungal pathogens. There are a number of such defensins expressed in various plant tissues with differing antifungal activity and spectrum. Relatively little is known about the modes of action and biological roles of these proteins. Our previous work on a virally encoded fungal toxin, KP4, from Ustilago maydis and subsequently with the plant defensin, MsDef1, from Medicago sativa demonstrated that some of these proteins specifically blocked calcium channels in both fungi and animals. The results presented here demonstrate that KP4 and three plant defensins, MsDef1, MtDef2, and RsAFP2, all inhibit root growth in germinating Arabidopsis seeds at low micromolar concentrations. We have previously demonstrated that a fusion protein composed of Rab GTPase (RabA4b) and enhanced yellow fluorescent protein (EYFP) is dependent upon calcium gradients for localization to the tips of the growing root hairs in Arabidopsis thaliana. Using this tip-localized fusion protein, we demonstrate that all four proteins rapidly depolarize the growing root hair and block growth in a reversible manner. This inhibitory activity on root and root hair is not directly correlated with the antifungal activity of these proteins and suggests that plants apparently express targets for these antifungal proteins. The data presented here suggest that plant defensins may have roles in regulating plant growth and development. Killer protein 4 (KP4) is a well studied viral toxin secreted by the maize smut fungus Ustilago maydis that kills sensitive Ustilago strains as well as inhibits Fusarium and plant root growth by inhibiting calcium uptake. Numerous small, cysteine-rich proteins have been shown to play a critical role in fungal-plant-bacterial associations. The discovery of six KP4-like genes in F. verticillioides precipitated efforts to understand their function and evolutionary origin. Analysis of publicly available genomic sequence identified 31 additional KP4-like genes from a range of Ascomycota, a Basidiomycota, and the moss Physcomitrella patens. Sequence comparison and phylogenetic analysis indicate that the viral KP4 and the moss and fungal KP4-like genes evolved from a common ancestor providing evidence for lateral gene transfer between kingdoms. Six genes of the 37 total genes are predicted to encode a protein with two, non-identical KP4-like domains in tandem separated by 29-56 amino acids. The results suggest that two independent events led to the dual-domain KP4 genes present in different lineages of the Ascomycota. Understanding the nature and function of KP4-like proteins in mycotoxin-producing species like Fusarium may help to limit plant diseases and increase food safety and food production. The corn smut fungus, Ustilago maydis, is a global pathogen responsible for extensive agricultural losses. Control of corn smut using traditional breeding has met with limited success because natural resistance to U. maydis is organ specific and involves numerous maize genes. Here, we present a transgenic approach by constitutively expressing the Totivirus antifungal protein KP4, in maize. Transgenic maize plants expressed high levels of KP4 with no apparent negative impact on plant development and displayed robust resistance to U. maydis challenges to both the stem and ear tissues in the greenhouse. More broadly, these results demonstrate that a high level of organ independent fungal resistance can be afforded by transgenic expression of this family of antifungal proteins.