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Which programming language has been used for implementing GWAR? | Stata | MOTIVATION: In the context of genome-wide association studies (GWAS), there is a
variety of statistical techniques in order to conduct the analysis, but, in most
cases, the underlying genetic model is usually unknown. Under these
circumstances, the classical Cochran-Armitage trend test (CATT) is suboptimal.
Robust procedures that maximize the power and preserve the nominal type I error
rate are preferable. Moreover, performing a meta-analysis using robust
procedures is of great interest and has never been addressed in the past. The
primary goal of this work is to implement several robust methods for analysis
and meta-analysis in the statistical package Stata and subsequently to make the
software available to the scientific community.
RESULTS: The CATT under a recessive, additive and domit model of inheritance
as well as robust methods based on the Maximum Efficiency Robust Test statistic,
the MAX statistic and the MIN2 were implemented in Stata. Concerning MAX and
MIN2, we calculated their asymptotic null distributions relying on numerical
integration resulting in a great gain in computational time without losing
accuracy. All the aforementioned approaches were employed in a fixed or a random
effects meta-analysis setting using summary data with weights equal to the
reciprocal of the combined cases and controls. Overall, this is the first
complete effort to implement procedures for analysis and meta-analysis in GWAS
using Stata.
AVAILABILITY AND IMPLEMENTATION: A Stata program and a web-server are freely
available for academic users at http://www.compgen.org/tools/GWAR.
CONTACT: [email protected].
SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics
online. |
Describe f-scLVM | Single-cell RNA-sequencing (scRNA-seq) allows studying heterogeneity in gene expression in large cell populations. Such heterogeneity can arise due to technical or biological factors, making decomposing sources of variation difficult. F-scLVM (factorial single-cell latent variable model) is a method based on factor analysis that uses pathway annotations to guide the inference of interpretable factors underpinning the heterogeneity. The model jointly estimates the relevance of individual factors, refines gene set annotations, and infers factors without annotation. F-scLVM robustly decomposes scRNA-seq datasets into interpretable components, thereby facilitating the identification of novel subpopulations. | Author information:
(1)European Molecular Biology Laboratory, European Bioinformatics Institute
(EMBL-EBI), Wellcome Genome Campus, Hinxton, Cambridge, CB10 1SD, UK.
[email protected].
(2)Current address: Helmholtz Zentrum München-German Research Center for
Environmental Health, Institute of Computational Biology, Neuherberg, Germany.
[email protected].
(3)European Molecular Biology Laboratory, European Bioinformatics Institute
(EMBL-EBI), Wellcome Genome Campus, Hinxton, Cambridge, CB10 1SD, UK.
(4)St Vincent's Institute of Medical Research, 41 Victoria Parade, Fitzroy,
Victoria, 3065, Australia.
(5)European Molecular Biology Laboratory, European Bioinformatics Institute
(EMBL-EBI), Wellcome Genome Campus, Hinxton, Cambridge, CB10 1SD, UK.
[email protected].
(6)Cancer Research UK Cambridge Institute, Cambridge, UK. [email protected].
(7)Wellcome Trust Sanger Institute, Wellcome Genome Campus, Hinxton, Cambridge,
UK. [email protected].
(8)European Molecular Biology Laboratory, European Bioinformatics Institute
(EMBL-EBI), Wellcome Genome Campus, Hinxton, Cambridge, CB10 1SD, UK.
[email protected].
(9)European Molecular Biology Laboratory (EMBL), Genome Biology Unit,
Meyerhofstr. 1, 69117, Heidelberg, Germany. [email protected]. |
Does promoter shape vary across populations? | Yes. Promoter shape varies across populations and affects promoter evolution and expression noise. This is accompanied by differences in the expression levels of different genes, which may reflect differences in their regulatory mechanisms. | Animal promoters initiate transcription either at precise positions (narrow
promoters) or dispersed regions (broad promoters), a distinction referred to as
promoter shape. Although highly conserved, the functional properties of
promoters with different shapes and the genetic basis of their evolution remain
unclear. Here we used natural genetic variation across a panel of 81 Drosophila
lines to measure changes in transcriptional start site (TSS) usage, identifying
thousands of genetic variants affecting transcript levels (strength) or the
distribution of TSSs within a promoter (shape). Our results identify promoter
shape as a molecular trait that can evolve independently of promoter strength.
Broad promoters typically harbor shape-associated variants, with signatures of
adaptive selection. Single-cell measurements demonstrate that variants
modulating promoter shape often increase expression noise, whereas heteroallelic
interactions with other promoter variants alleviate these effects. These results
uncover new functional properties of natural promoters and suggest the
minimization of expression noise as an important factor in promoter evolution. |
How large is a lncRNAs? | lncRNAs are defined as RNA transcripts longer than 200 nucleotides that are not transcribed into proteins | BACKGROUND: Long noncoding RNAs (lncRNAs) are more than 200 nucleotides in
length and lack transcriptional ability. The biological function of lncRNAs in
oral squamous cell carcinoma (OSCC) remains unclear. The aim of this study was
to identify the dysfunction of lncRNA in OSCC.
RESULTS: We analyzed the transcriptome profiles of human OSCC tissues and paired
adjacent normal tissues from two patients through a next-generation sequencing
approach. A total of 14 lncRNAs were upregulated (fold change ≥3) and 13 were
downregulated (fold change ≤-3) in OSCC tissues compared with the adjacent
normal tissues. SOX21-AS1 was subjected to further analysis, revealing that the
expression levels of SOX21-AS1 significantly decreased in OSCC compared with the
adjacent normal tissue. The promoter activity of SOX21-AS1 was obviously
suppressed by in vitro methylation. The DNA methylation status of the SOX21-AS1
promoter was analyzed using combined bisulfite restriction analysis, revealing
that the aberrant promoter hypermethylation of SOX21-AS1 was observed frequently
in OSCC tissues. The effects of SOX21-AS1 on cell proliferation and invasion
were examined through transient transfection. Our data showed that SOX21-AS1
could significantly suppress oral cancer cell growth and invasion. Furthermore,
the low expression level of SOX21-AS1 was significantly correlated with an
advanced stage (P = 0.047), large tumor size (P = 0.033), and poor
disease-specific survival in OSCC patients (P = 0.002).
CONCLUSIONS: SOX21-AS1 was identified as susceptible dysfunction correlated with
promoter hypermethylation in OSCC. Low SOX21-AS1 expression may be an adverse
prognostic biomarker for OSCC. |
What is MLE4901? | MLE4901 is an oral neurikinin 3 receptor antagonist that has been shown to safely and effectively relieve hot flush symptoms in menopausal women without the need for oestrogen exposure. | BACKGROUND: Hot flushes affect 70% of menopausal women and often severely impact
physical, psychosocial, sexual, and overall wellbeing. Hormone replacement
therapy is effective but is not without risk. Neurokinin B signalling is
increased in menopausal women, and has been implicated as an important mediator
of hot flushes.
METHODS: This phase 2, randomised, double-blind, placebo-controlled,
single-centre, crossover trial assessed the effectiveness of an oral neurokinin
3 receptor antagonist (MLE4901) on menopausal hot flushes. Eligible participants
were healthy women aged 40-62 years, having seven or more hot flushes in every
24 h of which some were reported as being severe or bothersome, who had not had
a menstrual period for at least 12 months, and who had not been taking any
medication shown to improve menopausal flushes in the preceding 8 weeks.
Participants received 4 weeks of MLE4901 (40 mg, orally, twice daily) and
placebo (orally, twice daily) in random order separated by a 2 week washout
period. Randomisation was completed by a central computer, and participants were
allocated to treatment number in numerical order. The primary outcome was the
total number of hot flushes during the final week of both treatment periods.
Analyses were by intention to treat and per protocol using generalised linear
mixed models and standard crossover analysis. All analyses were prespecified in
the study protocol. The trial is registered at ClinicalTrials.gov, number
NCT02668185.
FINDINGS: 68 women were screened between Feb 3 and Oct 10, 2016, of which 37
were randomly assigned and included in an intention-to-treat analysis. 28
participants completed the trial and were included in a per-protocol analysis.
MLE4901 significantly reduced the total weekly number of hot flushes by 45
percentage points (95% CI 22-67) compared with the placebo (intention-to-treat
adjusted means: placebo 49·01 [95% CI 40·81-58·56] vs MLE4901 19·35
[15·99-23·42]; adjusted estimate of difference 29·66 [17·39-42·87], p<0·0001).
Treatment was well tolerated. Three participants developed a transaminase rise
(alanine aminotransferase 4·5-5·9 times the upper limit of normal) with a normal
bilirubin 28 days after starting MLE4901, which normalised within 90 days.
INTERPRETATION: Treatment with a neurokinin 3 receptor antagonist (MLE4901)
could be practice changing as it safely and effectively relieves hot flush
symptoms without the need for oestrogen exposure. Larger scale studies of longer
duration are now indicated.
FUNDING: UK Medical Research Council and National Institute for Health Research. |
What is the drug chloroquine or hydroxychloroquine used for? | Chloroquine (CQ) has been used for decades as the primary chemotherapeutic drug for the treatment of malaria.
Hydroxychloroquine (HCQ), a 4-aminoquinolone antimalarial, is regarded as the oral therapy of choice for cutaneous and systemic lupus erythematosus (SLE). It is also licensed for rheumatoid arthritis (RA).
Chloroquine is a potent inhibitor of SARS coronavirus infection and spread. | OBJECTIVE: We have previously shown that exogenous administration of the nuclear
protein high mobility group box 1 (HMGB1) improves angiogenesis after tissue
ischemia. Antagonizing HMGB1 prolongs muscle necrosis and deters regeneration.
In this study, we evaluated HMGB1 expression in peripheral arterial disease
(PAD) and the mechanisms that promote its release in a murine model of hindlimb
ischemia. Specifically, we investigated how chloroquine (CQ), a commonly
employed disease-modifying antirheumatic drug, promotes HMGB1 release from
muscle. We hypothesized that CQ could increase HMGB1 locally and systemically,
allowing it to mediate recovery from ischemic injury.
METHODS: Muscle biopsies were performed on patients undergoing lower extremity
surgery for non-PAD-related disease as well as for claudication and critical
limb ischemia. Clinical symptoms and ankle-brachial indices were recorded for
each patient. HMGB1 was detected in muscle sections using immunohistochemical
staining. Unilateral femoral artery ligation was performed on both wild-type and
inducible HMGB1 knockout mice. Wild-type mice were administered intraperitoneal
CQ 2 weeks before and after femoral artery ligation. Laser Doppler perfusion
imaging was used to determine perfusion recovery. Serum and tissue levels of
HMGB1 were measured at designated time points. In vitro, cultured C2C12
myoblasts were treated with increasing doses of CQ. HMGB1, autophagosome
formation, p62/SQSTM1 accumulation, caspase-1 expression and activity, and
lactate dehydrogenase levels were measured in supernatants and cell lysates.
RESULTS: Nuclear expression of HMGB1 was prominent in patients with claudication
and critical limb ischemia (P < .05) compared with controls. CQ-treated mice had
elevated serum HMGB1 and diffuse HMGB1 staining in muscle (P < .01). In
wild-type mice, CQ treatment resulted in higher laser Doppler perfusion imaging
ratios in the ischemic limb at 7 days (P < .03) and less fat replacement after
2 weeks (P < .03). In cultured myoblasts, CQ induced autophagosome accumulation,
inhibited p62/SQSTM-1 degradation, and activated caspase-1.
CONCLUSIONS: HMGB1 is prominently expressed in PAD muscle but mostly confined to
the nucleus. Our in vivo data suggest that HMGB1 mobilization into the
sarcoplasm and serum can be increased with CQ, possibly through
caspase-1-mediated pathways. Whereas HMGB1 can be released by many cell types,
these studies suggest that the muscle may be an important additional source that
is relevant in PAD. Background Hydroxychloroquine (HCQ), a 4-aminoquinolone antimalarial, is
regarded as the oral therapy of choice for cutaneous and systemic lupus
erythematosus (SLE). It is also licensed for rheumatoid arthritis (RA). Studies
of HCQ-treated patients with SLE or RA have demonstrated a positive correlation
between whole-blood HCQ levels and clinical response. Such studies have involved
measuring whole-blood concentrations at any given time point after HCQ ingestion
assuming that steady-state concentrations would undergo limited fluctuation over
a daily interval because HCQ has a long half-life. This approach might not
sufficiently take into account the potential intra-patient variation in HCQ
blood levels that can occur over a 24-hour period. Such variation, if
significant, could affect the credibility of any concentration-response
relationship provided from these previous studies. Objectives The objectives of
this report are to: (a) investigate the intra-patient variation in HCQ
whole-blood levels and (b) suggest an optimum time for sampling patients for
future studies. Methods Six patients were recruited with cutaneous lupus
erythematosus who had each been on HCQ 200 mg twice daily for at least six
months, so that they were at steady-state. Each patient was fasted overnight and
had standardized meals and dosing schedule. Whole blood was sampled at seven
time points over 24 hours. Whole-blood HCQ levels were measured with
high-performance liquid chromatography using gradient elution, fluorimetric
detection and chloroquine as an internal standard. The assay had a mean inter-
and intra-day coefficient of variation of 10% and 5% respectively and a limit of
detection of 5ng/ml. Results HCQ levels appeared to follow a biphasic pattern
over the sampling period. Maximum levels were noted a median of four hours
(range 2-6) after ingestion. Median intra-patient variation between trough and
peak levels, 'Cmax' ((peak - trough)/trough × 100%), was 27% (range 8-150%).
Conclusions This study demonstrated that whole-blood HCQ levels vary 27%
(median, range 8-150%) within an individual over a 12-hour period. Drug levels
might differ between individuals because of multiple factors, including variable
adherence to medication. Measuring HCQ levels for assessment of drug adherence
could be valuable in the 'real-world' clinical setting. This could be assessed
by taking a blood sample at any time following HCQ ingestion. If patients were
found to have very low or undetectable levels of HCQ, non-adherence to HCQ
should be suspected. Chloroquine (CQ) has been used for decades as the primary chemotherapeutic drug
for the treatment of malaria. The emergence of drug resistance in Plasmodium
falciparum has been considered to be because of the excessive use of
antimalarial drugs worldwide. Moreover, the intense distribution and prevalence
of chloroquine-resistant strains in endemic regions has aided the incidence of
more complications to malaria treatment and control. Due to the lack of
literature that portrays evident molecular mechanisms of drug resistance, it has
been difficult to understand the drug resistance conferred by Plasmodium
species. Intensive research on CQ drug resistance has identified the association
of P. falciparum chloroquine resistance transporter protein (PfCRT), which
belongs to the drug/metabolite transporter and EamA-like superfamily.
Additionally, it has shown that K76 T mutation in PfCRT protein has mainly
attributed to CQ resistance than other mutations. This study deals with the
development of an in silico model of the PfCRT protein and its interaction with
the CQ ligand molecule as well as the biochemical and biophysical
characterization of the transmembrane domain 1 (TMD 1) peptide of the PfCRT
protein. The physiochemical analysis of the PfCRT protein identified basic
differences between the wild and mutant forms of the protein, as well as
identifying the high hydrophobic nature of the mutant-type protein. The tertiary
structure of the PfCRT protein was predicted and interaction with CQ revealed
different active pocket binding regions in both the wild and mutant form of
PfCRT proteins. The CQ2+ molecule interacts with TMD 10 of the wild-type PfCRT
protein, whereas it interacts with TMD 1 of the mutant-type protein. Studies on
the TMD 1 peptide revealed the insertion of the peptide in the micelles adopting
stable alpha-helical structure. Binding studies with the CQ molecule detected
high binding affinity toward the mutant-type TMD 1 peptide rather than the
wild-type, thus confirming that the TMD 1 peptide is involved in substrate
selectivity. Our findings help to characterize the structure of the PfCRT
protein and the role played by the TMD 1 region in CQ resistance using in silico
and biochemical approaches. Molecular docking and ligand binding studies confirm
that TMD 1 is involved in substrate selectivity and aids in CQ efflux, thereby
contributing to the parasite's CQ drug resistance mechanism. |
Does xaliproden improve prognosis of amyotrophic lateral sclerosis? | No. There is not sufficient high quality evidence that xaliproden significantly improves prognosis of amyotrophic lateral sclerosis patients. | BACKGROUND: Motor neuron disease (MND), which is also known as amyotrophic
lateral sclerosis (ALS), causes a wide range of symptoms but the evidence base
for the effectiveness of the symptomatic treatment therapies is limited.
OBJECTIVES: To summarise the evidence from Cochrane Systematic Reviews of all
symptomatic treatments for MND.
METHODS: We searched the Cochrane Database of Systematic Reviews (CDSR) on 15
November 2016 for systematic reviews of symptomatic treatments for MND. We
assessed the methodological quality of the included reviews using the Assessment
of Multiple Systematic Reviews (AMSTAR) tool and the GRADE approach. We followed
standard Cochrane study (review) selection and data extraction procedures. We
reported findings narratively and in tables.
MAIN RESULTS: We included nine Cochrane Systematic Reviews of interventions to
treat symptoms in people with MND. Three were empty reviews with no included
randomised controlled trials (RCTs); however, all three reported on non-RCT
evidence and the remaining six included mostly one or two studies. We deemed all
of the included reviews of high methodological quality. Drug therapy for
painThere is no RCT evidence in a Cochrane Systematic Review exploring the
efficacy of drug therapy for pain in MND. Treatment for crampsThere is evidence
(13 RCTs, N = 4012) that for the treatment of cramps in MND, compared to
placebo:- memantine and tetrahydrocannabinol (THC) are probably ineffective
(moderate-quality evidence);- vitamin E may have little or no effect
(low-quality evidence); and- the effects of L-threonine, gabapentin, xaliproden,
riluzole, and baclofen are uncertain as the evidence is either very low quality
or the trial specified the outcome but did not report numerical data.The review
reported adverse effects of riluzole, but it is not clear whether other
interventions had adverse effects. Treatment for spasticityIt is uncertain
whether an endurance-based exercise programme improved spasticity or quality of
life, measured at three months after the programme, as the quality of evidence
is very low (1 RCT, comparison "usual activities", N = 25). The review did not
evaluate other approaches, such as use of baclofen as no RCTs were available.
Mechanical ventilation for supporting respiratory functionNon-invasive
ventilation (NIV) probably improves median survival and quality of life in
people with respiratory insufficiency and normal to moderately impaired bulbar
function compared to standard care, and improves quality of life but not
survival for people with poor bulbar function (1 RCT, N = 41, moderate-quality
evidence; a second RCT did not provide data). The review did not evaluate other
approaches such as tracheostomy-assisted ('invasive') ventilation, or assess
timing of NIV initiation. Treatment for sialorrhoeaA single session of botulinum
toxin type B injections to parotid and submandibular glands probably improves
sialorrhoea and quality of life at up to 4 weeks compared to placebo injections,
but not at 8 or 12 weeks after the injections (moderate-quality evidence from 1
placebo-controlled RCT, N = 20). The review authors found no trials of other
approaches. Enteral tube feeding for supporting nutritionThere is no RCT
evidence in a Cochrane Systematic Review to support benefit or harms of enteral
tube feeding in supporting nutrition in MND. Repetitive transcranial magnetic
stimulationIt is uncertain whether repetitive transcranial magnetic stimulation
(rTMS) improves disability or limitation in activity in MND in comparison with
sham rTMS (3 RCTs, very low quality evidence, N = 50). Therapeutic exerciseThere
is evidence that exercise may improve disability in MND at three months after
the exercise programme, but not quality of life, in comparison with "usual
activities" or "usual care" including stretching (2 RCTs, low-quality evidence,
N = 43). Multidisciplinary careThere is no RCT evidence in a Cochrane Systematic
Review to demonstrate any benefit or harm for multidisciplinary care in MND.None
of the reviews, other than the review of treatment for cramps, reported that
adverse events occurred. However, the trials were too small for reliable adverse
event reporting.
AUTHORS' CONCLUSIONS: This overview has highlighted the lack of robust evidence
in Cochrane Systematic Reviews on interventions to manage symptoms resulting
from MND. It is important to recognise that clinical trials may fail to
demonstrate efficacy of an intervention for reasons other than a true lack of
efficacy, for example because of insufficient statistical power, the wrong
choice of dose, insensitive outcome measures or inappropriate participant
eligibility. The trials were mostly too small to reliably assess adverse effects
of the treatments. The nature of MND makes it difficult to research clinically
accepted or recommended practice, regardless of the level of evidence supporting
the practice. It would not be ethical, for example, to design a
placebo-controlled trial for treatment of pain in MND or to withhold
multidisciplinary care where such care is available. It is therefore highly
unlikely that there will ever be classically designed placebo-controlled RCTs in
these areas.We need more research with appropriate study designs, robust
methodology, and of sufficient duration to address the changing needs-of people
with MND and their caregivers-associated with MND disease progression and
mortality. There is a significant gap in studies assessing the effectiveness of
interventions for symptoms relating to MND, such as pseudobulbar emotional
lability and cognitive and behavioural difficulties. Future studies should use
appropriate outcome measures that are reliable, have internal and external
validity, and are sensitive to change in what is being measured (such as quality
of life). |
What is Telangiectasia? | Telangiectasia (macroscopically visible dilated skin vessels) | Scleroderma (progressive systemic sclerosis) is a systemic autoimmune disorder
characterised by skin sclerosis, calcinosis and changes in microvasculature. The
etiology of the disease is unknown but both genetic and environmental factors
have been implicated. Telangiectasia (macroscopically visible dilated skin
vessels) occurring primarily on the hands and face, are a prominent feature in
scleroderma and are present in the majority of patients. Similarly,
telangiectasia are found in patients with hereditary hemorrhagic telangiectasia
(HHT), a mutational disorder of the germline genes endoglin and ALK-1, members
of the TGFbeta receptor family, expressed on endothelial cells. Our study
investigated the number, distribution and microscopic characteristics of
telangiectasia in both limited (n = 29) and diffuse scleroderma (n = 9) and
compared findings with 3 patients with HHT. In limited scleroderma, the mean
number of telangiectasia (hand and face) was 36 (0-150) compared with 23 (0-135)
in diffuse scieroderma. A significant correlation was observed between the
number of telangiectasia on the face and on the hands (p = 0.014). The total
number of telangiectasia correlated significantly with the disease duration (p =
0.009). The spatial distribution of the telangiectasia appeared to be random on
both hands and foreface in contrast with the distribution of subcutaneous
calcification of the hands which occurred predomitly on the distal and flexor
surfaces of the first, second and fifth digits. Nailfold microscopic
capillaroscopy was performed on 12 patients. No significant correlation was
observed between capillary diameter or density and with total number of
telangiectasia observed macroscopically. The distribution and microscopic
appearance of telangiectasia in scleroderma appeared very similar to those
observed in HHT. In view of these similarities we therefore conclude that
telangiectactic development in scleroderma may be associated with disorders of
the TGFb receptor family proteins found on the microvasculature. Neonatal lupus erythematosus (NLE) is an uncommon condition usually associated
with maternal anti-Ro autoantibodies. The cutaneous lesions of NLE are usually
transient, disappearing about six months after birth, but telangiectasia is a
rare complication of NLE which persists. Telangiectasias are small focal red
macules and papules created by abnormally prominent capillaries, venules, and
arterioles and are a characteristic marker of connective tissue diseases. We
report the case of an infant diagnosed with NLE presenting typical annular
lesions, positive ANA and positive anti-Ro antibodies. By five months of age,
both ANA and anti-Ro antibodies were negative and the annular cutaneous lesions
had gradually faded, but small scattered focal red macules appeared on the face,
especially in the peri-orbital area and scalp. The cutaneous lupus disappeared
but the telangiectasia persisted. We would like to suggest that the diagnosis of
NLE should be considered when cutaneous telangiectasias are observed in infants. BACKGROUND: Juvenile polyposis syndrome is a domit GI polyposis syndrome
defined by ≥ 5 GI juvenile polyps or ≥ 1 juvenile polyps with a family history
of juvenile polyposis. Mutations in BMPR1A or SMAD4 are found in 50% of
individuals. Hereditary hemorrhagic telangiectasia is a domit disorder
characterized by epistaxis, visceral arteriovenous malformations, and
telangiectasias. Hereditary hemorrhagic telangiectasia is diagnosed when ≥ 3
criteria including clinical manifestations or a family history, are present. A
juvenile polyposis-hereditary hemorrhagic telangiectasia overlap syndrome has
previously been reported in 22% of patients with juvenile polyposis due to a
SMAD4 mutation.
OBJECTIVE: Our objective was to determine the prevalence and clinical
manifestations of hereditary hemorrhagic telangiectasia by Curacao criteria in
our juvenile polyposis SMAD4 patients.
DESIGN, PATIENTS, AND SETTING: This was a cohort study of juvenile polyposis
patients in our inherited colon cancer registries. Hereditary hemorrhagic
telangiectasia manifestations were obtained from medical records, patient
contact, and/or prospective hereditary hemorrhagic telangiectasia screening. The
Curacao criteria was used for diagnosis of hereditary hemorrhagic telangiectasia
(≥ 3 criteria diagnostic; 2 criteria suspect of).
MAIN OUTCOME MEASURES: Prevalence and clinical manifestations of hereditary
hemorrhagic telangiectasia in juvenile polyposis SMAD4 patients.
RESULTS: Forty-one juvenile polyposis families were identified. Genetic testing
was available for individuals within 18 families. SMAD4 mutations were found in
21 relatives in 9 families. Eighty-one percent of SMAD4 patients had hereditary
hemorrhagic telangiectasia and 14% were suspected of having hereditary
hemorrhagic telangiectasia. Epistaxis and asthma are the most common symptoms in
our overlap patients. Symptomatic and subclinical arteriovenous malformations
were noted near universally.
LIMITATIONS: There was a single, tertiary referral center.
CONCLUSIONS: Nearly all juvenile polyposis SMAD4 patients have the overlap
syndrome. The clinical implications and need for hereditary hemorrhagic
telangiectasia screening are important factors for genetic testing in juvenile
polyposis. Health care providers must be cognizant of the juvenile
polyposis-hereditary hemorrhagic telangiectasia overlap syndrome and the
implications for management of these patients. |
Is cathepsin L active in endosomes? | yes,
Cathepsin L is found in the Late Endosome/Lysosome. | Hendra virus is a highly pathogenic paramyxovirus classified as a biosafety
level four agent. The fusion (F) protein of Hendra virus is critical for
promoting viral entry and cell-to-cell fusion. To be fusogenically active,
Hendra virus F must undergo endocytic recycling and cleavage by the
endosomal/lysosomal protease cathepsin L, but the route of Hendra virus F
following internalization and the recycling signals involved are poorly
understood. We examined the intracellular distribution of Hendra virus F
following endocytosis and showed that it is primarily present in Rab5- and
Rab4-positive endosomal compartments, suggesting that cathepsin L cleavage
occurs in early endosomes. Hendra virus F transmembrane domain (TMD) residues
S490 and Y498 were found to be important for correct Hendra virus F recycling,
with the hydroxyl group of S490 and the aromatic ring of Y498 important for this
process. In addition, changes in association of isolated Hendra virus F TMDs
correlated with alterations to Hendra virus F recycling, suggesting that
appropriate TMD interactions play an important role in endocytic trafficking. Ebola virus infection can cause severe hemorrhagic fever with a high mortality
in humans. The outbreaks of Ebola viruses in 2014 represented the most serious
Ebola epidemics in history and greatly threatened public health worldwide. The
development of additional effective anti-Ebola therapeutic agents is therefore
quite urgent. In this study, via high throughput screening of Food and Drug
Administration-approved drugs, we identified that teicoplanin, a glycopeptide
antibiotic, potently prevents the entry of Ebola envelope pseudotyped viruses
into the cytoplasm. Furthermore, teicoplanin also has an inhibitory effect on
transcription- and replication-competent virus-like particles, with an IC50 as
low as 330 nm Comparative analysis further demonstrated that teicoplanin is able
to block the entry of Middle East respiratory syndrome (MERS) and severe acute
respiratory syndrome (SARS) envelope pseudotyped viruses as well. Teicoplanin
derivatives such as dalbavancin, oritavancin, and telavancin can also inhibit
the entry of Ebola, MERS, and SARS viruses. Mechanistic studies showed that
teicoplanin blocks Ebola virus entry by specifically inhibiting the activity of
cathepsin L, opening a novel avenue for the development of additional
glycopeptides as potential inhibitors of cathepsin L-dependent viruses. Notably,
given that teicoplanin has routinely been used in the clinic with low toxicity,
our work provides a promising prospect for the prophylaxis and treatment of
Ebola, MERS, and SARS virus infection. Human coronavirus 229E (HCoV-229E), a causative agent of the common cold, enters
host cells via two distinct pathways: one is mediated by cell surface proteases,
particularly transmembrane protease serine 2 (TMPRSS2), and the other by
endosomal cathepsin L. Thus, specific inhibitors of these proteases block virus
infection. However, it is unclear which of these pathways is actually utilized
by HCoV-229E in the human respiratory tract. Here, we examined the mechanism of
cell entry used by a pseudotyped virus bearing the HCoV-229E spike (S) protein
in the presence or absence of protease inhibitors. We found that, compared with
a laboratory strain isolated in 1966 and passaged for a half century, clinical
isolates of HCoV-229E were less likely to utilize cathepsin L; rather, they
showed a preference for TMPRSS2. Two amino acid substitutions (R642M and N714K)
in the S protein of HCoV-229E clinical isolates altered their sensitivity to a
cathepsin L inhibitor, suggesting that these amino acids were responsible for
cathepsin L use. After 20 passages in HeLa cells, the ability of the isolate to
use cathepsin increased so that it was equal to that of the laboratory strain;
this increase was caused by an amino acid substitution (I577S) in the S protein.
The passaged virus showed a reduced ability to replicate in differentiated
airway epithelial cells cultured at an air-liquid interface. These results
suggest that the endosomal pathway is disadvantageous for HCoV-229E infection of
human airway epithelial cells; therefore, clinical isolates are less able to use
cathepsin.
IMPORTANCE: Many enveloped viruses enter cells through endocytosis. Viral spike
proteins drive the fusion of viral and endosomal membranes to facilitate
insertion of the viral genome into the cytoplasm. Human coronavirus 229E
(HCoV-229E) utilizes endosomal cathepsin L to activate the spike protein after
receptor binding. Here, we found that clinical isolates of HCoV-229E
preferentially utilize the cell surface protease TMPRSS2 rather than endosomal
cathepsin L. The endosome is a main site of Toll-like receptor recognition,
which then triggers an innate immune response; therefore, HCoV-229E presumably
evolved to bypass the endosome by entering the cell via TMPRSS2. Thus, the virus
uses a simple mechanism to evade the host innate immune system. Therefore,
therapeutic agents for coronavirus-mediated diseases, such as severe acute
respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS), should
target cell surface TMPRSS2 rather than endosomal cathepsin. |
Which tissues express the ACE2 protein? | Abundant ACE2 immunostaining was found in lung, kidney, heart, and islets of pancreas, but not in hepatocytes | Severe acute respiratory syndrome (SARS) is an emerging infectious disease
associated with a new coronavirus, SARS-CoV. Pulmonary involvement is the
domit clinical feature but extra-pulmonary manifestations are also common.
Factors that account for the wide spectrum of organ system involvement and
disease severity are poorly understood and the pathogenesis of SARS-CoV
infection remains unclear. Angiotensin converting enzyme 2 (ACE2) has recently
been identified as the functional cellular receptor for SARS-CoV. Studies of the
tissue and cellular distribution of SARS-CoV, and ACE2 protein expression,
reveal new insights into the pathogenesis of this deadly disease. ACE2 is
expressed at high level in the primary target cells of SARS-CoV, namely
pneumocytes and surface enterocytes of the small intestine. Despite the fact
that SARS-CoV can infect the lung and intestine, the tissue responses in these
two organs are different. All other tissues and cell types expressing ACE2 may
be potential targets of SARS-CoV infection. Remarkably, endothelial cells, which
express ACE2 to a high level, have not been shown to be infected by SARS-CoV.
There is also evidence that cell types without detectable ACE2 expression may
also be infected by the virus. Furthermore, studies in a new human cell culture
model have indicated that the presence of ACE2 alone is not sufficient for
maintaining viral infection. Therefore, other virus receptors or co-receptors
may be required in different tissues. Moreover, the interaction between SARS-CoV
and the immunological or lymphoid system remains to be defined. It is clear that
we are only at the dawn of our understanding of the pathogenesis of SARS. As our
knowledge of the pathogenic mechanisms improves, a more rational approach to
therapeutic and vaccine development can be designed in order to combat this new
and fatal human disease. Angiotensin (Ang)-converting enzyme (ACE) 2 cleaves Ang-II into the vasodilator
peptide Ang-(1-7), thus acting as a pivotal element in balancing the local
effects of these peptides. ACE2 has been identified in various tissues and is
supposed to be a modulator of cardiovascular function. Decreases in ACE2
expression and activity have been reported in models of hypertension, heart
failure, atherosclerosis, diabetic nephropathy and others. In addition, the
expression level and/or activity are affected by other renin-angiotensin system
components (e.g., ACE and AT1 receptors). Local inhibition or global deletion of
brain ACE2 induces a reduction in baroreflex sensitivity. Moreover, ACE2-null
mice have been shown to exhibit either blood pressure or cardiac dysfunction
phenotypes. On the other hand, over-expression of ACE2 exerts protective effects
in local tissues, including the brain. In this review, we will first summarize
the major findings linking ACE2 to cardiovascular function in the periphery then
focus on recent discoveries related to ACE2 in the CNS. Finally, we will unveil
new tools designed to address the importance of central ACE2 in various
diseases, and discuss the potential for this carboxypeptidase as a new target in
the treatment of hypertension and other cardiovascular diseases. Multiple organ damage in severe acute respiratory syndrome (SARS) patients is
common; however, the pathogenesis remains controversial. This study was to
determine whether the damage was correlated with expression of the SARS
coronavirus receptor, angiotensin converting enzyme 2 (ACE2), in different
organs, especially in the endocrine tissues of the pancreas, and to elucidate
the pathogenesis of glucose intolerance in SARS patients. The effect of clinical
variables on survival was estimated in 135 SARS patients who died, 385
hospitalized SARS patients who survived, and 19 patients with non-SARS
pneumonia. A total of 39 SARS patients who had no previous diabetes and received
no steroid treatment were compared to 39 matched healthy siblings during a
3-year follow-up period. The pattern of SARS coronavirus receptor-ACE2 proteins
in different human organs was also studied. Significant elevations in oxygen
saturation, serum creatinine, lactate dehydrogenase, creatine kinase MB
isoenzyme, and fasting plasma glucose (FPG), but not in alanine transaminase
were predictors for death. Abundant ACE2 immunostaining was found in lung,
kidney, heart, and islets of pancreas, but not in hepatocytes. Twenty of the 39
followed-up patients were diabetic during hospitalization. After 3 years, only
two of these patients had diabetes. Compared with their non-SARS siblings, these
patients exhibited no significant differences in FPG, postprandial glucose
(PPG), and insulin levels. The organ involvements of SARS correlated with organ
expression of ACE2. The localization of ACE2 expression in the endocrine part of
the pancreas suggests that SARS coronavirus enters islets using ACE2 as its
receptor and damages islets causing acute diabetes. ACE2 (angiotensin converting enzyme 2) plays a critical role in the local tissue
RAS (renin-angiotensin system) by hydrolysing the potent hypertensive and
mitogenic peptide AngII (angiotensin II). Changes in the levels of ACE2 have
been observed in a number of pathologies, including cardiovascular disease, but
little is known of the mechanisms regulating its expression. In the present
study, therefore, the potential role of miRNAs in the regulation of ACE2
expression in primary human cardiac myofibroblasts was examined. Putative
miRNA-binding sites were identified in the 3'-UTR of the ACE2 transcript using
online prediction algorithms. Two of these, miR-200b and miR-421, were selected
for further analysis. A reporter system using the 3'-UTR of ACE2 fused to the
coding region of firefly luciferase was used to determine the functionality of
the identified binding sites in vitro. This identified miR-421, but not
miR-200b, as a potential regulator of ACE2. The ability of miR-421, an miRNA
implicated in the development of thrombosis, to down-regulate ACE2 expression
was subsequently confirmed by Western blot analysis of both primary cardiac
myofibroblasts and transformed cells transfected with a synthetic miR-421
precursor. Real-time PCR analysis of miR-421 revealed widespread expression in
human tissues. miR-421 levels in cardiac myofibroblasts showed significant
inter-patient variability, in keeping with the variability of ACE2 expression we
have observed previously. In conclusion, the present study is the first to
demonstrate that ACE2 may be subject to post-transcriptional regulation and
reveals a novel potential therapeutic target, miR-421, which could be exploited
to modulate ACE2 expression in disease. |
In which chromosome are transgenes inserted in the case of the LiPS-A3S line? | Transgenesis of human pluripotent stem cells (hPSCs) can enable and empower a variety of studies in stem cell research, including lineage tracing and functional genetics studies. While in recent years much progress has been made in the development of tools for gene targeting, little attention has been given to the identification of sites in the human genome where transgenes can be inserted and reliably expressed. One cell line/clone, LiPS-A3, has an integration site in chromosome 15 maintaining robust expression without silencing. Different transgenes can be inserted therein rapidly and efficiently through recombinase-mediated cassette exchange (RMCE). The LiPS-A3 line can greatly facilitate the insertion of reporter and other genes in hPSCs. Targeting transgenes in the LiPS-A3S genomic locus can find broad applications in stem cell research and possibly cell and gene therapy. | |
What is a J pouch? | The j pouch is a colonic j-pouch with anastomosis to the rectal stump. It is an accepted form of reconstruction after low anterior resection (lar) for rectal carcinoma. | PURPOSE: This study compared outcomes after laparoscopic (LAP) or conventional
(open) total proctocolectomy with outcomes after ileal J-pouch anal anastomosis
(IPAA) at a single institution.
METHODS: Charts from 133 familial adenomatous polyposis patients (1997-2013)
were reviewed. Demographic data (age, sex, color, American Society of
Anesthesiologists [ASA] status, previous surgery, and body mass index) and
surgical outcomes (length of stay, early and late morbidity, reoperation, and
mortality rates) were compared among 63 patients undergoing IPAA.
RESULTS: Demographic features were similar among patients (25 open and 38 LAP).
Conversely, colorectal cancer at diagnosis prevailed in the open group (60%
versus 31.6%; P = .02). Tumor stages (P = .65) and previous surgery index (20%
versus 10.5%; P = .46) were similar. Surgical length was longer for LAP (374
versus 281 minutes, P = .003). Short-term complication rates (28% versus 28.9%),
hospital stay (10.9 versus 8.9 days), and total long-term reoperations (28%
versus 21%) were not statistically different. However, major late morbidity (16%
versus 2.6%; P < .001) and late reoperation rates (16% versus 5.2%; P < .05)
were greater among open patients. Both groups did not differ regarding pouch
failure rates (8% versus 5.2%). There was no operative mortality in the present
series.
CONCLUSIONS: (1) LAP IPAA is a safe procedure associated with a low conversion
rate, (2) short-term results showed no clear advantages for both approaches, and
(3) a greater risk of major late complications and late reoperations should be
expected after open procedures. AIM: There is no consensus as to which ileoanal pouch design provides better
outcomes after restorative proctocolectomy. This study compares different pouch
designs.
METHOD: A systematic review of the literature was performed. A random effects
meta-analytical model was used to compare adverse events and functional outcome.
RESULTS: Thirty comparative studies comparing J, W, S and K pouch designs were
included. No significant differences were identified between the different pouch
designs with regard to anastomotic dehiscence, anastomotic stricture, pelvic
sepsis, wound infection, pouch fistula, pouch ischaemia, perioperative
haemorrhage, small bowel obstruction, pouchitis and sexual dysfunction. The W
and K designs resulted in fewer cases of pouch failure compared with the J and S
designs. J pouch construction resulted in a smaller maximum pouch volume
compared with W and K pouches. Stool frequency per 24 h and during daytime was
higher following a J pouch than W, S or K constructions. The J design resulted
in increased faecal urgency and seepage during daytime compared with the K
design. The use of protective pads during daytime and night-time was greater
with a J pouch compared to S or K. The use of antidiarrhoeal medication was
greater after a J reservoir than a W reservoir. Difficulty in pouch evacuation
requiring intubation was higher with an S pouch than with W or J pouches.
CONCLUSION: Despite its ease of construction and comparable complication rates,
the J pouch is associated with higher pouch failure rates and worse function.
Patient characteristics, technical factors and surgical expertise should be
considered when choosing pouch design. Ileal pouch-anal anastomosis, or J pouch, surgery has become the procedure of
choice for treatment of medically refractory ulcerative colitis and familial
adenomatous polyposis. Overall, this operation is associated with a low rate of
postoperative morbidity and good long-term function. However, when complications
develop, there is a heavy reliance on imaging to facilitate an accurate
diagnosis. Reported postoperative complication rates range from 5% to 35%.
Complications generally can be categorized as structural, inflammatory, or
neoplastic conditions. Structural complications include leaks, strictures,
afferent and efferent limb syndromes, and pouch prolapse. Inflammatory
conditions include cuffitis, pouchitis, and Crohn disease of the pouch. In
addition, a variety of neoplastic conditions can develop in the pouch. Overall,
pouchitis and leaks are the most common complications, occurring in up to 50%
and 20% of individuals, respectively. Many imaging modalities are used to
evaluate the J pouch and associated postoperative complications. The indications
and various surgical techniques for J pouch surgery, normal postoperative
appearance of the pouch, and most common associated complications are reviewed.
In addition, the various imaging findings associated with J pouch surgery are
described and illustrated. The radiologist's familiarity with the potential
complications of the pouch can facilitate appropriate imaging, hasten an
accurate diagnosis, and aid in rendering proper management. ©RSNA, 2018. |
What is the function of the protein encoded by the gene NKCC2? | The protein function as an Na-K-Cl cotransporter. | AAV9 vector provides efficient gene transfer in all segments of the renal
nephron, with minimum expression in non-renal cells, when administered
retrogradely via the ureter. It is important to restrict the transgene
expression to the desired cell type within the kidney, so that the physiological
endpoints represent the function of the transgene expressed in that specific
cell type within kidney. We hypothesized that segment-specific gene expression
within the kidney can be accomplished using the highly efficient AAV9 vectors
carrying the promoters of genes that are expressed exclusively in the desired
segment of the nephron in combination with administration by retrograde infusion
into the kidney via the ureter. We constructed AAV vectors carrying eGFP under
the control of: kidney-specific cadherin (KSPC) gene promoter for expression in
the entire nephron; Na+/glucose co-transporter (SGLT2) gene promoter for
expression in the S1 and S2 segments of the proximal tubule; sodium, potassium,
2 chloride co-transporter (NKCC2) gene promoter for expression in the thick
ascending limb of Henle's loop (TALH); E-cadherin (ECAD) gene promoter for
expression in the collecting duct (CD); and cytomegalovirus (CMV) early promoter
that provides expression in most of the mammalian cells, as control. We tested
the specificity of the promoter constructs in vitro for cell type-specific
expression in mouse kidney cells in primary culture, followed by retrograde
infusion of the AAV vectors via the ureter in the mouse. Our data show that AAV9
vector, in combination with the segment-specific promoters administered by
retrograde infusion via the ureter, provides renal nephron segment-specific gene
expression. With no lysine kinase 4 (WNK4) is essential to activate the thiazide-sensitive
NaCl cotransporter (NCC) along the distal convoluted tubule, an effect central
to the phenotype of familial hyperkalemic hypertension. Although effects on
potassium and sodium channels along the connecting and collecting tubules have
also been documented, WNK4 is typically believed to have little role in
modulating sodium chloride reabsorption along the thick ascending limb of the
loop of Henle. Yet wnk4-/- mice (knockout mice lacking WNK4) do not demonstrate
the hypocalciuria typical of pure distal convoluted tubule dysfunction. Here, we
tested the hypothesis that WNK4 also modulates bumetanide-sensitive Na-K-2Cl
cotransporter (NKCC2) function along the thick ascending limb. We confirmed that
w nk4-/- mice are hypokalemic and waste sodium chloride, but are also
normocalciuric. Results from Western blots suggested that the phosphorylated
forms of both NCC and NKCC2 were in lower abundance in wnk4-/- mice than in
controls. This finding was confirmed by immunofluorescence microscopy. Although
the initial response to furosemide was similar in wnk4-/- mice and controls, the
response was lower in the knockout mice when reabsorption along the distal
convoluted tubule was inhibited. Using HEK293 cells, we showed that WNK4
increases the abundance of phosphorylated NKCC2. More supporting evidence that
WNK4 may modulate NKCC2 emerges from a mouse model of WNK4-mediated familial
hyperkalemic hypertension in which more phosphorylated NKCC2 is present than in
controls. These data indicate that WNK4, in addition to modulating NCC, also
modulates NKCC2, contributing to its physiological function in vivo. |
Is celecoxib effective for amyotrophic lateral sclerosis? | No. In a clinical trial, celecoxib did not have a beneficial effect on patients with amyotrophic lateral sclerosis. | OBJECTIVE: To determine whether chronic treatment with celecoxib, a
cyclooxygenase-2 inhibitor that has been shown to be beneficial in preclinical
testing, is safe and effective in amyotrophic lateral sclerosis (ALS).
METHODS: A double-blind, placebo-controlled, clinical trial was conducted. Three
hundred research subjects with ALS were randomized (2:1) to receive celecoxib
(800 mg/day) or placebo for 12 months. The primary outcome measure was the rate
of change in upper extremity motor function measured by the maximum voluntary
isometric contraction strength. Secondary end points included safety, survival,
change in cerebrospinal fluid prostaglandin E(2) levels, and changes in the rate
of decline of leg and grip strength, vital capacity, ALS Functional Rating
Scale-Revised, and motor unit number estimates.
RESULTS: Celecoxib did not slow the decline in muscle strength, vital capacity,
motor unit number estimates, ALS Functional Rating Scale-Revised, or affect
survival. Celecoxib was well tolerated and was not associated with an increased
frequency of adverse events. Prostaglandin E(2) levels in cerebrospinal fluid
were not elevated at baseline and did not decline with treatment.
INTERPRETATION: At the dosage studied, celecoxib did not have a beneficial
effect on research subjects with ALS, and it was safe. A biological effect of
celecoxib was not demonstrated in the cerebrospinal fluid. Further studies of
celecoxib at a dosage of 800 mg/day in ALS are not warranted. |
Is the protein MCL-1 anti-apoptotic? | Yes, MCL-1 is an anti-apoptotic protein. | Mantle cell lymphoma (MCL) is an aggressive and incurable maligt disease.
Despite of general chemotherapy, relapse and mortality are common, highlighting
the need for the development of novel targeted drugs or combination of
therapeutic regimens. Recently, several drugs that target the B-cell receptor
(BCR) signaling pathway, especially the Bruton's tyrosine kinase (BTK) inhibitor
ibrutinib, have demonstrated notable therapeutic effects in relapsed/refractory
patients, which indicate that pharmacological inhibition of BCR pathway holds
promise in MCL treatment. Here, we have developed a novel irreversible BTK
inhibitor, PLS-123, that has more potent and selective anti-tumor activity than
ibrutinib in vitro and in vivo. Using in vitro screening, we discovered that the
combination of PLS-123 and the mammalian target of rapamycin (mTOR) inhibitor
everolimus exert synergistic activity in attenuating proliferation and motility
of MCL cell lines. Simultaneous inhibition of BTK and mTOR resulted in marked
induction of apoptosis and cell cycle arrest in the G1 phase, which were
accompanied by upregulation of pro-apoptotic proteins (cleaved Caspase-3,
cleaved PARP and Bax), repression of anti-apoptotic proteins (Mcl-1, Bcl-xl and
XIAP), and downregulation of regulators of the G1/S phase transition (CDK2,
CDK4, CDK6 and Cyclin D1). Gene expression profile analysis revealed
simultaneous treatment with these agents led to inhibition of the JAK2/STAT3,
AKT/mTOR signaling pathways and SGK1 expression. Finally, the anti-tumor and
pro-apoptotic activities of combination strategy have also been demonstrated
using xenograft mice models. Taken together, simultaneous suppression of BTK and
mTOR may be indicated as a potential therapeutic modality for the treatment of
MCL. |
Describe the mechanism of action of Trilaciclib. | Trilaciclib is cyclin-dependent kinase 4 and 6 (CDK4/6) inhibitor, which act by inhibiting progression from the G1 to S phases of the cell cycle. | Conventional cytotoxic chemotherapy is highly effective in certain cancers but
causes dose-limiting damage to normal proliferating cells, especially
hematopoietic stem and progenitor cells (HSPCs). Serial exposure to cytotoxics
causes a long-term hematopoietic compromise ("exhaustion"), which limits the use
of chemotherapy and success of cancer therapy. We show that the coadministration
of G1T28 (trilaciclib), which is a small-molecule inhibitor of cyclin-dependent
kinases 4 and 6 (CDK4/6), contemporaneously with cytotoxic chemotherapy protects
murine hematopoietic stem cells (HSCs) from chemotherapy-induced exhaustion in a
serial 5-fluorouracil treatment model. Consistent with a cell-intrinsic effect,
we show directly preserved HSC function resulting in a more rapid recovery of
peripheral blood counts, enhanced serial transplantation capacity, and reduced
myeloid skewing. When administered to healthy human volunteers, G1T28
demonstrated excellent in vivo pharmacology and transiently inhibited bone
marrow (BM) HSPC proliferation. These findings suggest that the combination of
CDK4/6 inhibitors with cytotoxic chemotherapy should provide a means to
attenuate therapy-induced BM exhaustion in patients with cancer. BACKGROUND: Chemotherapy-induced damage of hematopoietic stem and progenitor
cells (HSPC) causes multi-lineage myelosuppression. Trilaciclib is an
intravenous CDK4/6 inhibitor in development to proactively preserve HSPC and
immune system function during chemotherapy (myelopreservation). Preclinically,
trilaciclib transiently maintains HSPC in G1 arrest and protects them from
chemotherapy damage, leading to faster hematopoietic recovery and enhanced
antitumor immunity.
PATIENTS AND METHODS: This was a phase Ib (open-label, dose-finding) and phase
II (randomized, double-blind placebo-controlled) study of the safety, efficacy
and PK of trilaciclib in combination with etoposide/carboplatin (E/P) therapy
for treatment-naive extensive-stage small-cell lung cancer patients. Patients
received trilaciclib or placebo before E/P on days 1-3 of each cycle. Select end
points were prespecified to assess the effect of trilaciclib on myelosuppression
and antitumor efficacy.
RESULTS: A total of 122 patients were enrolled, with 19 patients in part 1 and
75 patients in part 2 receiving study drug. Improvements were seen with
trilaciclib in neutrophil, RBC (red blood cell) and lymphocyte measures. Safety
on trilaciclib+E/P was improved with fewer ≥G3 adverse events (AEs) in
trilaciclib (50%) versus placebo (83.8%), primarily due to less hematological
toxicity. No trilaciclib-related ≥G3 AEs occurred. Antitumor efficacy assessment
for trilaciclib versus placebo, respectively, showed: ORR (66.7% versus 56.8%,
P = 0.3831); median PFS [6.2 versus 5.0 m; hazard ratio (HR) 0.71; P = 0.1695];
and OS (10.9 versus 10.6 m; HR 0.87; P = 0.6107).
CONCLUSION: Trilaciclib demonstrated an improvement in the patient's
tolerability of chemotherapy as shown by myelopreservation across multiple
hematopoietic lineages resulting in fewer supportive care interventions and dose
reductions, improved safety profile, and no detriment to antitumor efficacy.
These data demonstrate strong proof-of-concept for trilaciclib's
myelopreservation benefits.
CLINICAL TRAIL NUMBER: NCT02499770. |
How is ZP-PTH delivered to patients? | ZP-PTH uses a transdermal drug-coated microneedle patch system. | |
Which disease is ZP-PTH used for? | ZP-PTH is used for the treatment of osteoporosis. | |
Which gene is mutated in the classic Bartter's syndrome? | Classic Bartter's syndrome has been demonstrated to result from defective chloride transport across the basolateral membrane in the distal nephron due to mutations in the chloride channel gene CLCNKB. | The term "Bartter's syndrome" comprises a set of autosomal recessively inherited
renal tubular disorders characterized by hypokalemia, metabolic alkalosis,
hyperreninism, and hyperaldosteronism but normal blood pressure. Additional
clinical and biochemical features led to a classification into phenotypically
different tubulopathies: Gitelman's syndrome, hyperprostaglandin E syndrome
(antenatal Bartter's syndrome), and classic Bartter's syndrome. Gitelman's
syndrome results from mutations in the SLC12A3 gene encoding the human
thiazide-sensitive sodium chloride cotransporter, leading to impaired
reabsorption of sodium chloride in the distal convoluted tubule. Genetic
heterogeneity of hyperprostaglandin E syndrome has been demonstrated by
identification of mutations in the SLC12A1 gene as well as in the KCNJ1 gene.
Mutations in SLC12A1 coding for the bumetanide-sensitive sodium potassium 2
chloride cotransporter (NKCC2) cause defective reabsorption of sodium chloride
in the thick ascending limb of Henle's loop. Mutations in KCNJ1 leading to loss
of function of the potassium channel ROMK disrupt potassium recycling back to
the tubule lumen and inhibit thereby the NKCC2 activity. A third gene for
hyperprostaglandin E syndrome has been mapped to the short arm of chromosome 1,
and it remains to be evaluated whether other genes are involved in the
pathogenesis of this disease. Classic Bartter's syndrome has been demonstrated
to result from defective chloride transport across the basolateral membrane in
the distal nephron due to mutations in the chloride channel gene CLCNKB. This
article reviews the molecular genetic approach that has led to identification of
genetic defects underlying the different hypokalemic tubulopathies. BACKGROUND: Progressive renal failure in patients with classic Bartter's
syndrome (cBS) due to inactivating mutations in CLCNKB gene is extraordinarily
rare.
DISCUSSION: We describe a 17-year-old Chinese boy who presented with progressive
muscle weakness and renal failure. He was diagnosed as BS of unknown type at the
age of 9 months and treated with indomethacin (2 mg/kg/day) and potassium
chloride (KCl) supplementation (1.5 mEq/kg/day) for hypokalemia (2.5 mmol/l). At
the age of 12 years, serum K+ was 3.0 mmol/l and creatinine reached 2.0 mg/dl.
On admission, his blood pressure was normal but volume status was depleted.
Urinalysis was essentially normal. Biochemical studies showed hypokalemia (K+
2.4 mmol/l) with a high transtubular K+ gradient (TTKG) 9.6, metabolic alkalosis
(HCO3- 28.4 mmol/l), normomagnesemia (2.0 mg/dl), severe renal failure (BUN 94
mg/dl, Cr 6.3 mg/dl), and hypocalciuria (urine calcium/creatinine ratio 0.02
mg/mg). Abdominal sonography revealed bilateral small size kidneys without
nephrocalcinosis or renal stones. After the withdrawal of indomethacin with
regular KCl and adequate fluid supplementation for 1 year, serum creatinine and
K+ levels have been maintained at 4.0 mg/dl and 3.3 mmol/l, respectively. Direct
sequencing of NKCC2, ROMK, ClC-Kb, and NCCT in this patient disclosed a novel
homozygous missense mutation (GGG to GAG, G470E) in CLCNKB. This G470E mutation
was not identified in 100 healthy Chinese subjects. Long-term therapy of
non-steroidal anti-inflammatory drugs (NSAIDs), prolonged hypokalemia, chronic
volume depletion, and underlying genetic variety may contribute to the
deterioration of his renal function. The cautious use of NSAIDs, aggressive
correction of hypokalemia, and avoidance of severe volume depletion may prevent
the irreversible renal damage in patients with BS due to a Cl- channel defect. |
What is the purpose of the Unique Connectivity of Uncharged Compounds (UC2) search tool? | The Unique Connectivity of Uncharged Compounds (UC2) search tool uses unique connectivity of uncharged compounds for metabolite annotation by database searching in mass spectrometry-based metabolomics. | SUMMARY: For metabolite annotation in metabolomics, variations in the registered
states of compounds (charged molecules and multiple components, such as salts)
and their redundancy among compound databases could be the cause of
misannotations and hamper immediate recognition of the uniqueness of metabolites
while searching by mass values measured using mass spectrometry. We developed a
search system named UC2 (Unique Connectivity of Uncharged Compounds), where
compounds are tentatively neutralized into uncharged states and stored on the
basis of their unique connectivity of atoms after removing their stereochemical
information using the first block in the hash of the IUPAC International
Chemical Identifier, by which false-positive hits are remarkably reduced, both
charged and uncharged compounds are properly searched in a single query and
records having a unique connectivity are compiled in a single search result.
AVAILABILITY AND IMPLEMENTATION: The UC2 search tool is available free of charge
as a REST web service (http://webs2.kazusa.or.jp/mfsearcher) and a Java-based
GUI tool.
CONTACT: [email protected].
SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics
online. |
Name a selective NK3R agonist. | Senktide is a highly potent and selective NK3R agonist. | Women during perimenopausal period experience a range of symptoms, which
interfere with physical, sexual, and social life. About 65-75% of symptoms
connected with postmenopausal period are vasomotor symptoms (VMS), such as hot
flushes and night sweats. Hot flushes are subjective sensation of heat
associated with cutaneous vasodilatation and drop in core temperature. It is
suspected that VMS are strongly correlated with pulsatile oversecretion of
gonadotropin-releasing hormone (GnRH) and subsequently luteinizing hormone (LH).
Evidence has accumulated in parallel showing that lack of negative feedback of
steroid hormones synthesized in ovary causes overactivation of hypertrophied
kisspeptin/neurokinin B/dynorphin (KNDy) neurons, located in infundibular
nucleus. Oversecretion of both kisspeptin (KISS1) and neurokinin B (NKB), as
well as downregulation of dynorphin, plays domit role in creation of GnRH
pulses. This in turn causes VMS. Administration of senktide, highly potent and
selective NK3R agonist, resulted in increase of serum LH concentration,
induction of VMS, increase in heart rate, and skin temperature in postmenopausal
women. These finding suggest that modulation of KNDy neurons may become new
therapeutic approach in the treatment of VMS. |
What is the target of the drug Olmesartan? | Olmesartan (OL) is the pharmacologically active metabolite of Olmesartan medoxomil (OM), an FDA-approved angiotensin II receptor antagonist for administrating cardiovascular diseases | Olmesartan (OL) is the pharmacologically active metabolite of Olmesartan
medoxomil (OM), an FDA-approved angiotensin II receptor antagonist for
administrating cardiovascular diseases. The drug has been found to have
potential effects on diverse protein kinase signaling involved in the
pathogenesis of atherosclerosis, either by directly inhibiting the hub kinases
or by indirectly modulating marginal members in the signaling pathways. In the
present study, we computationally model the kinase-chemical Interaction Profile
between six OL-related chemicals (i.e. OL, OM, Valsartan [VL], Losartan [LS],
Candesartan [CD] and Telmisartan [TL]) and 23 human protein kinases in
atherosclerosis. The profile is analyzed systematically at molecular level to
identify unexpected kinase targets for OL. There is a good consistence between
co-citation frequency and affinity scoring for the chemical association with
kinase candidates; the OL and its analogs VL and LS exhibit a similar binding
profile to the atherosclerosis kinase spectrum. It is suggested that the
Ser/Thr-specific kinases PI3Kα and ROCK1 are potential druggable targets of OL
for atherosclerosis therapy. As a paradigm, kinase assays reveal that the
inhibitory potency of OL and Y-27632 (positive control) on ROCK1 is determined
at micromolar level, while the OM (negative control) possesses no detectable
activity for the kinase. Two post hoc analyses in self-identified black and white patients with
hypertension evaluated the angiotensin II receptor blocker azilsartan medoxomil
(AZL-M) and the fixed-dose combination of AZL-M with chlorthalidone (AZL-M/CLD)
versus the ARB olmesartan (OLM) and the OLM fixed-dose combination with
hydrochlorothiazide (OLM/HCTZ). One analysis pooled 1,610 patients from two
6-week randomized controlled trials to compare once daily AZL-M 40 mg, AZL-M 80
mg, OLM 40 mg, and placebo. The second analysis included 1,020 patients from a
12-week randomized controlled trial to compare once daily AZL-M/CLD 40/25 mg,
AZL-M/CLD 80/25 mg, and OLM/HCTZ 40/25 mg. Efficacy end points were 24-hour mean
ambulatory and clinic systolic and diastolic blood pressure (SPB/DBP) and the
percentage of patients achieving clinic SBP/DBP targets. Treatment with AZL-M 80
mg lowered mean clinic SBP by 12.5 mm Hg (p <0.01 vs OLM), treatment with
AZL-M/CLD 40 mg/25 mg lowered mean ambulatory SBP by 31.0 mm Hg and mean clinic
SBP by 39.3 mm Hg (both p <0.05 vs OLM/HCTZ), and treatment with AZL-M/CLD 80
mg/25 mg lowered mean ambulatory SBP by 34.4 mm Hg (p <0.01 vs OLM/HCTZ) and
mean clinic SBP by 39.2 mm Hg (p <0.05 vs OLM/HCTZ). Target BP goals were
achieved more frequently with AZL-M versus OLM and with AZL-M/CLD versus
OLM/HCTZ. In conclusion, in both black and white patients, BP was lowered more
effectively with AZL-M versus OLM and with AZL-M/CLD versus OLM/HCTZ. The
AZL-M/CLD 40 mg/25 mg combination resulted in a statistically significant
reduction in BP in both black and white patients. |
In which cells does TLR7 escape X-chromosome inactivation? | The tlr7 gene encodes by an x chromosome locus. Tlr7 is encoded by an x-chromosome inactivation in immune cells from women and klinefelter syndrome patients. | Toll-like receptor 7 (TLR7) is critical to the induction of antiviral immunity,
but TLR7 dosage is also a key pathogenic factor in systemic lupus erythematosus
(SLE), an autoimmune disease with strong female bias. SLE prevalence is also
elevated in individuals with Klinefelter syndrome, who carry one or more
supernumerary X chromosomes, suggesting that the X chromosome complement
contributes to SLE susceptibility. TLR7 is encoded by an X chromosome locus, and
we examined here whether the TLR7 gene evades silencing by X chromosome
inactivation in immune cells from women and Klinefelter syndrome males.
Single-cell analyses of TLR7 allelic expression demonstrated that substantial
fractions of primary B lymphocytes, monocytes, and plasmacytoid dendritic cells
not only in women but also in Klinefelter syndrome males express TLR7 on both X
chromosomes. Biallelic B lymphocytes from women displayed greater TLR7
transcriptional expression than the monoallelic cells, correlated with higher
TLR7 protein expression in female than in male leukocyte populations. Biallelic
B cells were preferentially enriched during the TLR7-driven proliferation of
CD27+ plasma cells. In addition, biallelic cells showed a greater than twofold
increase over monoallelic cells in the propensity to immunoglobulin G class
switch during the TLR7-driven, T cell-dependent differentiation of naive B
lymphocytes into immunoglobulin-secreting cells. TLR7 escape from X inactivation
endows the B cell compartment with added responsiveness to TLR7 ligands. This
finding supports the hypothesis that enhanced TLR7 expression owing to
biallelism contributes to the higher risk of developing SLE and other autoimmune
disorders in women and in men with Klinefelter syndrome. |
Which tool has been developed for prediction of single-cell DNA methylation states using deep learning? | DeepCpG is a computational approach based on deep neural networks to predict methylation states in single cells. By evaluating DeepCpG on single-cell methylation data from five cell types generated using alternative sequencing protocols it turns out that DeepCpG yields substantially more accurate predictions than previous methods. | Recent technological advances have enabled DNA methylation to be assayed at
single-cell resolution. However, current protocols are limited by incomplete CpG
coverage and hence methods to predict missing methylation states are critical to
enable genome-wide analyses. We report DeepCpG, a computational approach based
on deep neural networks to predict methylation states in single cells. We
evaluate DeepCpG on single-cell methylation data from five cell types generated
using alternative sequencing protocols. DeepCpG yields substantially more
accurate predictions than previous methods. Additionally, we show that the model
parameters can be interpreted, thereby providing insights into how sequence
composition affects methylation variability. |
When was vaxchora first licensed by the FDA? | Vaxchora was licensed by the FDA on June 10 2016. | Effective and easy to administer cholera vaccines are in need more than ever,
for at risk populations and travellers alike. In many parts of the world cholera
is still endemic, causing outbreaks and constituting repeatedly serious public
health problems. The oral live cholera vaccine CVD 103-HgR (Orochol, Mutachol),
the first genetically modified organism (GMO) used as vaccine, was in its time
(launched 1993, Switzerland) the ideal cholera vaccine: single-dose, protective
efficacy of 80-100% against moderate to severe cholera, acting within 8 days and
exhibiting excellent safety, indiscernible from placebo. However, there were
strong headwinds: In the 1990s the indication for cholera vaccines was generally
downplayed by experts and in 1997 the European Commission called for a
moratorium of GMOs which blocked the registration in the European Union. Thus,
demand for this vaccine remained low and in 2003 it was taken off the market for
economic reasons. After a decade in obscurity it (Vaxchora) has resurfaced
again, now produced in the U.S. and equipped with a U.S. FDA license (June 10,
2016). What had happened? This commentary gives a critical account of an almost
unbelievable string of misadventures, emerging adverse circumstances and
man-made failures which nearly killed this single-dose live oral cholera
vaccine. The good news is that patience and persistence lead to success in the
end, allowing good science to prevail for the benefit of those in need. |
What is the active ingredient of Eligard? | The active ingredient of Eligard is leuprorelin acetate. | |
Which company produces Eligard? | Eligard is produced by Astellas Pharma GmbH. | |
Which type of distance is used in the R-package XenofilteR? | The R-package XenofilteR separates mouse from human sequence reads based on the edit-distance between a sequence read and reference genome. | BACKGROUND: Mouse xenografts from (patient-derived) tumors (PDX) or tumor cell
lines are widely used as models to study various biological and preclinical
aspects of cancer. However, analyses of their RNA and DNA profiles are
challenging, because they comprise reads not only from the grafted human cancer
but also from the murine host. The reads of murine origin result in false
positives in mutation analysis of DNA samples and obscure gene expression levels
when sequencing RNA. However, currently available algorithms are limited and
improvements in accuracy and ease of use are necessary.
RESULTS: We developed the R-package XenofilteR, which separates mouse from human
sequence reads based on the edit-distance between a sequence read and reference
genome. To assess the accuracy of XenofilteR, we generated sequence data by in
silico mixing of mouse and human DNA sequence data. These analyses revealed that
XenofilteR removes > 99.9% of sequence reads of mouse origin while retaining
human sequences. This allowed for mutation analysis of xenograft samples with
accurate variant allele frequencies, and retrieved all non-synonymous somatic
tumor mutations.
CONCLUSIONS: XenofilteR accurately dissects RNA and DNA sequences from mouse and
human origin, thereby outperforming currently available tools. XenofilteR is
open source and available at https://github.com/PeeperLab/XenofilteR . |
How many copies of TP53 does the elephant genome contain? | Here, we show that the elephant genome encodes 20 copies of the tumor suppressor gene TP53 and that the increase in TP53 copy number occurred coincident with the evolution of large body sizes, the evolution of extreme sensitivity to genotoxic stress, and a hyperactive TP53 signaling pathway in the elephant (Proboscidean) lineage. While humans have 1 copy (2 alleles) of TP53, African elephants have at least 20 copies (40 alleles), including 19 retrogenes (38 alleles) with evidence of transcriptional activity measured by reverse transcription polymerase chain reaction. | |
Which company originally developed the drug Afrezza? | The inhaled insulin Technosphere, also known as Afrezza is produced by the MannKind Corporation. | Given the important role of insulin in the treatment of diabetes mellitus and in
light of common barriers to insulin use, new strategies for insulin delivery by
routes other than intravenous and subcutaneous injection have been investigated
since the discovery of insulin in the 1920s. Most companies researching and
developing pulmonary administration systems for the use of insulin announced the
termination of product development following the failure of the first US
FDA-approved inhaled insulin product, Exubera. One company in particular
continued their pursuit of a useful inhaled insulin product. MannKind
Corporation has developed a powder formulation of insulin that allows for a high
percentage of the administered insulin to be absorbed via the lung. Their
product, AFREZZA (Technosphere insulin), is currently under review by the FDA
for use in patients with diabetes. Technosphere insulin appears to overcome some
of the barriers that contributed to the market withdrawal of Exubera by the
manufacturer. Studies with Technosphere insulin have shown it to be a unique
insulin formulation in that it is very rapid acting, has a relatively short
duration of action, and is efficacious in terms of improved glycemic control
without contributing to increased weight gain or the incidence of hypoglycemia
when compared with other prandial insulin products. Additionally, Technosphere
insulin has demonstrated a favorable safety and tolerability profile in clinical
studies to date. |
Which tool exist for predicting drug synergy with deep learning? | Deep Learning has had an impact in many research areas by achieving new state-of-the-art model performance. DeepSynergy has been developed as a tool that uses chemical and genomic information as input information, a normalization strategy to account for input data heterogeneity, and conical layers to model drug synergies. | MOTIVATION: While drug combination therapies are a well-established concept in
cancer treatment, identifying novel synergistic combinations is challenging due
to the size of combinatorial space. However, computational approaches have
emerged as a time- and cost-efficient way to prioritize combinations to test,
based on recently available large-scale combination screening data. Recently,
Deep Learning has had an impact in many research areas by achieving new
state-of-the-art model performance. However, Deep Learning has not yet been
applied to drug synergy prediction, which is the approach we present here,
termed DeepSynergy. DeepSynergy uses chemical and genomic information as input
information, a normalization strategy to account for input data heterogeneity,
and conical layers to model drug synergies.
RESULTS: DeepSynergy was compared to other machine learning methods such as
Gradient Boosting Machines, Random Forests, Support Vector Machines and Elastic
Nets on the largest publicly available synergy dataset with respect to mean
squared error. DeepSynergy significantly outperformed the other methods with an
improvement of 7.2% over the second best method at the prediction of novel drug
combinations within the space of explored drugs and cell lines. At this task,
the mean Pearson correlation coefficient between the measured and the predicted
values of DeepSynergy was 0.73. Applying DeepSynergy for classification of these
novel drug combinations resulted in a high predictive performance of an AUC of
0.90. Furthermore, we found that all compared methods exhibit low predictive
performance when extrapolating to unexplored drugs or cell lines, which we
suggest is due to limitations in the size and diversity of the dataset. We
envision that DeepSynergy could be a valuable tool for selecting novel
synergistic drug combinations.
AVAILABILITY AND IMPLEMENTATION: DeepSynergy is available via
www.bioinf.jku.at/software/DeepSynergy.
CONTACT: [email protected].
SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics
online. |
Is ozanezumab effective for amyotrophic lateral sclerosis? | No. Ozanezumab did not show efficacy compared with placebo in patients with amyotrophic lateral sclerosis. Therefore, Nogo-A does not seem to be an effective therapeutic target in ALS. | BACKGROUND: Neurite outgrowth inhibitor A (Nogo-A) is thought to have a role in
the pathophysiology of amyotrophic lateral sclerosis (ALS). A monoclonal
antibody against Nogo-A showed a positive effect in the SOD1G93A mouse model of
ALS, and a humanised form of this antibody (ozanezumab) was well tolerated in a
first-in-human trial. Therefore, we aimed to assess the safety and efficacy of
ozanezumab in patients with ALS.
METHODS: This randomised, double-blind, placebo-controlled, phase 2 trial was
done in 34 centres in 11 countries. Patients aged 18-80 years with a diagnosis
of familial or sporadic ALS were randomly assigned (1:1), centrally according to
a computer-generated allocation schedule, to receive ozanezumab (15 mg/kg) or
placebo as intravenous infusions over 1 h every 2 weeks for 46 weeks, followed
by assessments at week 48 and week 60. Patients and study personnel were masked
to treatment assignment. The primary outcome was a joint-rank analysis of
function (ALS Functional Rating Scale-Revised) and overall survival, analysed at
48 weeks in all patients who received at least one dose of study drug. This
study is registered with ClinicalTrials.gov, number NCT01753076, and with
GSK-ClinicalStudyRegister.com, NOG112264, and is completed.
FINDINGS: Between Dec 20, 2012, and Nov 1, 2013, we recruited 307 patients, of
whom 303 were randomly assigned to receive placebo (n=151) or ozanezumab
(n=152). The adjusted mean of the joint-rank score was -14·9 (SE 13·5) for the
ozanezumab group and 15·0 (13·6) for the placebo group, with a least squares
mean difference of -30·0 (95% CI -67·9 to 7·9; p=0·12). Overall, reported
adverse events, serious adverse events, and adverse events leading to permanent
discontinuation of study drug or withdrawal from study were similar between the
treatment groups, except for dyspepsia (ten [7%] in the ozanezumab group vs four
[3%] in the placebo group), depression (11 [7%] vs five [3%]), and diarrhoea (25
[16%] vs 12 [8%]). Respiratory failure was the most common serious adverse event
(12 [8%] vs seven [5%]). At week 60, the number of deaths was higher in the
ozanezumab group (20 [13%]) than in the placebo group (16 [11%]), mainly as a
result of respiratory failure (ten [7%] vs five [3%]). Two deaths were
considered related to the study drug (bladder transitional cell carcinoma in the
ozanezumab group and cerebrovascular accident in the placebo group).
INTERPRETATION: Ozanezumab did not show efficacy compared with placebo in
patients with ALS. Therefore, Nogo-A does not seem to be an effective
therapeutic target in ALS.
FUNDING: GlaxoSmithKline. |
Is Dexmecamylamine effective for depression? | No. Antidepressant effect of Dexmecamylamine (TC-5214) was not observed in clinical trials. | TC-5214 (dexmecamylamine) is a nicotinic channel modulator that has previously
been evaluated for treatment of major depression disorder (MDD) and is currently
being evaluated by Targacept as a treatment for overactive bladder. A
comprehensive population pharmacokinetic (POP PK) model of TC-5214 was developed
using nonlinear mixed-effects modeling of pooled plasma concentration data from
6 early phase I studies in 179 healthy participants or patients with non-MDD and
1 phase II study in 68 MDD patients. Concentration-time profiles of TC-5214
after either single or multiple oral doses of TC-5214 was described by a
one-compartment model with first-order absorption with lag time and first-order
elimination. Covariate analysis revealed that creatinine clearance was a
significant covariate on clearance and that body weight significantly influenced
the central volume of distribution. The final model (with identified covariates)
was used to simulate steady-state exposure for patients with impaired renal
function. Results from forest plots reveal that patients with moderate to severe
renal impairment or end stage renal disease are associated with significantly
higher Cssmax and AUC compared to patients with normal renal function. The
proposed final POP PK model could be employed in defining a TC-5214 dosage
regimen in patients with impaired renal function. Safety and tolerability are important considerations when selecting patients'
treatment for major depressive disorder. We report the long-term safety and
tolerability of the nicotinic channel modulator dexmecamylamine (TC-5214),
adjunct to selective serotonin reuptake inhibitors
(SSRIs)/serotonin-norepinephrine reuptake inhibitors (SNRIs) in patients with
major depressive disorder and who had an inadequate response to antidepressants.
This 52-week, double-blind, placebo-controlled study explored the long-term
safety and tolerability of dexmecamylamine. Patients were randomized 3:1 to
receive flexibly dosed dexmecamylamine 1 to 4 mg adjunct to SSRI/SNRI or placebo
plus SSRI/SNRI. The patient population comprised inadequate responders from 2
Phase III acute dexmecamylamine studies (NCT01157078 [study 002], NCT01153347
[study 004]) and de novo patients who responded inadequately during a 6-week
open-label antidepressant treatment period preceding randomization. Safety and
tolerability were assessed by monitoring adverse events, vital signs, and
physical and laboratory parameters. Descriptive statistical analyses were
performed on most efficacy-related end points. Sustained efficacy was analyzed
using logistic regression. Overall, 813 patients were randomized (610 received
dexmecamylamine, 203 received placebo). In total, 82.4% and 84.6% of patients,
respectively, experienced an adverse event. Adverse events occurring more
frequently with dexmecamylamine vs placebo were constipation (19.6% vs 6.0%),
dizziness (12.0% vs 7.0%), and dry mouth (9.7% vs 5.0%). Back pain (2.8% vs
8.5%), weight increase (4.4% vs 7.0%), and fatigue (5.6 % vs 7.5%) occurred more
frequently in placebo-treated patients. No notable differences were observed
between dexmecamylamine and placebo for any secondary end point. In this
long-term study, safety and tolerability of dexmecamylamine were consistent with
that reported in acute Phase III studies of dexmecamylamine. |
Which cloud-based platform has been developed for comparing GWAS? | EasyGWAS is a cloud-based platform for comparing the results of Genome-Wide Association Studies (GWAS). | The ever-growing availability of high-quality genotypes for a multitude of
species has enabled researchers to explore the underlying genetic architecture
of complex phenotypes at an unprecedented level of detail using genome-wide
association studies (GWAS). The systematic comparison of results obtained from
GWAS of different traits opens up new possibilities, including the analysis of
pleiotropic effects. Other advantages that result from the integration of
multiple GWAS are the ability to replicate GWAS signals and to increase
statistical power to detect such signals through meta-analyses. In order to
facilitate the simple comparison of GWAS results, we present easyGWAS, a
powerful, species-independent online resource for computing, storing, sharing,
annotating, and comparing GWAS. The easyGWAS tool supports multiple species, the
uploading of private genotype data and summary statistics of existing GWAS, as
well as advanced methods for comparing GWAS results across different experiments
and data sets in an interactive and user-friendly interface. easyGWAS is also a
public data repository for GWAS data and summary statistics and already includes
published data and results from several major GWAS. We demonstrate the potential
of easyGWAS with a case study of the model organism Arabidopsis thaliana, using
flowering and growth-related traits. |
Can CMB305 be used against sarcomas? | Yes, the CMB205 vaccine is aimed at synovial sarcoma and myxoid/round cell liposarcoma patients. | INTRODUCTION: Synovial Sarcoma (SS) and Myxoid Round Cell Liposarcoma (MRCL) are
devastating sarcoma subtypes with few treatment options and poor outcomes in the
advanced setting. However, both these diseases may be ideal for novel
immunotherapies targeting the cancer-testis antigen, NY-ESO-1.
AREAS COVERED: In this review, we discuss the novel NY-ESO-1 targeted vaccine
regimen, CMB305. This regimen uses a unique integration-deficient,
dendritic-cell targeting lentiviral vector from the ZVex® platform, LV305, in
order to prime NY-ESO-1 specific T cells. LV305 has single agent activity, and,
in one case, caused a durable partial response in a refractory SS patient.
CMB305 also includes a boost from a NY-ESO-1 protein vaccine given along with a
potent toll-like-4 receptor agonist, glycopyranosyl lipid A. CMB305 induces
NY-ESO-1 specific T cell responses in both SS and MRC patients and these
patients had excellent overall survival (OS) outcomes in the initial phase I
study.
EXPERT COMMENTARY: CMB305 is a therapeutic vaccine regimen targeting NY-ESO-1
based on the lentiviral vaccine vector, LV305. Phase I studies have proven this
vaccine is active immunologically. Data suggesting this vaccine may improve OS
for SS and MRCL patients is exciting but early, and on-going work is testing the
impact of CMB305 on patient outcomes. |
What is Quadracel? | Quadracel (diphtheria and tetanus toxoids and acellular pertussis adsorbed and inactivated poliovirus vaccine, Sanofi Pasteur Inc.) is a new vaccination developed to condense the last dose of both DTaP and IPV so they do not have to be given separately, thus reducing the total number of vaccinations required. In a randomized, controlled, phase 3, pivotal trial, Quadracel proved to be as efficacious and safe as Daptacel (diphtheria and tetanus toxoids and acellular pertussis vaccine adsorbed, Sanofi Pasteur Inc.) and IPOL (poliovirus vaccine inactivated, Sanofi Pasteur Inc.), given separately, to children between the ages of 4 and 6 years. | INTRODUCTION: Vaccinations in school-aged children are required by state and
local law to maintain high vaccination coverage rates, as well as low rates of
vaccine-preventable diseases. Diphtheria, tetanus, and pertussis are childhood
diseases that can be life threatening; poliomyelitis, another childhood disease,
can be disabling. In turn, vaccinations were developed to provide protection
against these diseases. Today, several vaccinations are recommended for
children, including but not limited to diphtheria, tetanus, and pertussis (DTaP)
and poliomyelitis (IPV). DTaP requires five doses, and IPV requires four.
Quadracel (diphtheria and tetanus toxoids and acellular pertussis adsorbed and
inactivated poliovirus vaccine, Sanofi Pasteur Inc.) is a new vaccination
developed to condense the last dose of both DTaP and IPV so they do not have to
be given separately, thus reducing the total number of vaccinations required.
DISCUSSION: The Quadracel vaccine is an option for use in children who are
completing the DTaP and IPV series. In a randomized, controlled, phase 3,
pivotal trial, Quadracel proved to be as efficacious and safe as Daptacel
(diphtheria and tetanus toxoids and acellular pertussis vaccine adsorbed, Sanofi
Pasteur Inc.) and IPOL (poliovirus vaccine inactivated, Sanofi Pasteur Inc.),
given separately, to children between the ages of 4 and 6 years.
CONCLUSION: Quadracel should be recommended to parents who have children between
the ages of 4 and 6 years who meet the necessary administration criteria and
need to finalize their DTaP and IPV series. Quadracel's administration in the
vaccination series replaces one additional injection, which may benefit children
who are afraid of receiving shots and parents who need to schedule one less
doctor's appointment. |
What delivery system is used for the Fluzone Intradermal vaccine? | Fluzone was the first influenza vaccine licensed in the USA that uses a new microinjection system for intradermal delivery of vaccines (Soluvia(tm), Becton Dickinson). | |
Name two inhalable insulin products. | Despite discontinuation of the first inhalable insulin, Exubera(r), due to suboptimal market acceptance, development of orally inhaled insulin delivery systems has been galvanized by the recent approval of Afrezza(r). | INTRODUCTION: Delivery of therapeutic insulin via the pulmonary route has been
the most investigated non-invasive alternative to the commonly used subcutaneous
(SC) route for diabetes management. Despite discontinuation of the first
inhalable insulin, Exubera®, due to suboptimal market acceptance, development of
orally inhaled insulin delivery systems has been galvanized by the recent
approval of Afrezza® and several others awaiting approval.
AREAS COVERED: The scope of this review article includes the prospects for and
the challenges faced in developing inhaled insulin delivery systems; discussion
of orally inhaled therapeutic insulin delivery systems that were discontinued,
recently approved or are currently under active investigation; and formulation
approaches that have the potential to deliver insulin via the pulmonary route.
EXPERT OPINION: The pulmonary route is the most advantageous route for
non-invasive insulin delivery. Inhalable insulin therapeutics have the potential
to be successful, provided that the formulations can be made with modified
release patterns to substitute for both prandial and basal insulin injections,
the delivery devices are convenient and easy to use, and the long-term safety of
inhaled insulin is documented through extensive studies. |
How is the mouse Fxy gene evolving? | Here, we report that the rate of sequence divergence of the 3' end of the Fxy gene is much higher (estimated at 170-fold higher for synonymous sites) when pseudoautosomal (present on both the X and Y chromosomes) than when X-unique. | Genes evolve at different rates depending on the strength of selective pressure
to maintain their function. Chromosomal position can also have an influence [1]
[2]. The pseudoautosomal region (PAR) of mammalian sex chromosomes is a small
region of sequence identity that is the site of an obligatory pairing and
recombination event between the X and Y chromosomes during male meiosis [3] [4]
[5] [6]. During female meiosis, X chromosomes can pair and recombine along their
entire length. Recombination in the PAR is therefore approximately 10 times
greater in male meiosis compared with female meiosis [4] [5] [6]. The gene Fxy
(also known as MID1 [7]) spans the pseudoautosomal boundary (PAB) in the
laboratory mouse (Mus musculus domesticus, C57BL/6) such that the 5' three exons
of the gene are located on the X chromosome but the seven exons encoding the
carboxy-terminal two-thirds of the protein are located within the PAR and are
therefore present on both the X and Y chromosomes [8]. In humans [7] [9], the
rat, and the wild mouse species Mus spretus, the gene is entirely X-unique.
Here, we report that the rate of sequence divergence of the 3' end of the Fxy
gene is much higher (estimated at 170-fold higher for synonymous sites) when
pseudoautosomal (present on both the X and Y chromosomes) than when X-unique.
Thus, chromosomal position can directly affect the rate of evolution of a gene.
This finding also provides support for the suggestion that regions of the genome
with a high recombination frequency, such as the PAR, may have an intrinsically
elevated rate of sequence divergence. The mouse Fxy gene was translocated into the highly recombining pseudoautosomal
region comparatively recently in evolutionary terms. This event resulted in a
rapid increase of GC content. We investigated the consequences of the
translocation further by sequencing exons and introns of Fxy in various rodent
species. We found that the DNA fragment newly located in a highly recombining
context has acquired every property of a GC-rich isochore, namely increased GC
content (especially at the third codon positions of exons), shorter introns and
high density of minisatellites. These results strongly suggest that
recombination is the primary determit of the isochore organization of
mammalian genomes. |
How long in bp is the human pseudoautosomal region 2 (PAR2)? | The human pseudoautosomal region 2 (PAR2), which is located in the long arm of chromosome 9 (LTR6B) and consists of 32 exons, is320-kb long. | The human Y chromosome is composed of two different parts: a pseudoautosomal
region shared with the X chromosome which is responsible for sex chromosome
pairing and a Y-specific part that encodes the sex determining gene. Previously
we have shown that the pseudoautosomal gene MIC2 only rarely recombines between
the sex chromosomes and, based on the elevated recombination rates in the
pseudoautosomal region, we predicted that this gene would lie close to the
Y-specific region. In this report we describe a test of this prediction using
long-range restriction mapping techniques. We conclude that MIC2 is less than
200 kilobases (kb) away from Y-specific sequences. During these experiments we
have identified an HTF island in a position consistent with the proposed
location of the human sex determining gene. The pseudoautosomal regions (PAR1 and PAR2) of the human X and Y chromosomes
pair and recombine during meiosis. Thus genes in this region are not inherited
in a strictly sex-linked fashion. PAR1 is located at the terminal region of the
short arms and PAR2 at the tips of the long arms of these chromosomes. To date,
24 genes have been assigned to the PAR1 region. Half of these have a known
function. In contrast, so far only 4 genes have been discovered in the PAR2
region. Deletion of the PAR1 region results in failure of pairing and male
sterility. The gene SHOX (short stature homeobox-containing) resides in PAR1.
SHOX haploinsufficiency contributes to certain features in Turner syndrome as
well as the characteristics of Leri-Weill dyschondrosteosis. Only two of the
human PAR1 genes have mouse homologues. These do not, however, reside in the
mouse PAR1 region but are autosomal. The PAR regions seem to be relics of
differential additions, losses, rearrangements and degradation of the X and Y
chromosome in different mammalian lineages. Marsupials have three homologues of
human PAR1 genes in their autosomes, although, in contrast to mouse, do not have
a PAR region at all. The disappearance of PAR from other species seems likely
and this region will only be rescued by the addition of genes to both X and Y,
as has occurred already in lemmings. The present review summarizes the current
understanding of the evolution of PAR and provides up-to-date information about
individual genes residing in this region. The human sex chromosomes differ in sequence, except for the pseudoautosomal
regions (PAR) at the terminus of the short and the long arms, denoted as PAR1
and PAR2. The boundary between PAR1 and the unique X and Y sequences was
established during the divergence of the great apes. During a copy number
variation screen, we noted a paternally inherited chromosome X duplication in 15
independent families. Subsequent genomic analysis demonstrated that an
insertional translocation of X chromosomal sequence into the Y chromosome
generates an extended PAR [corrected].The insertion is generated by non-allelic
homologous recombination between a 548 bp LTR6B repeat within the Y chromosome
PAR1 and a second LTR6B repeat located 105 kb from the PAR boundary on the X
chromosome. The identification of the reciprocal deletion on the X chromosome in
one family and the occurrence of the variant in different chromosome Y
haplogroups demonstrate this is a recurrent genomic rearrangement in the human
population. This finding represents a novel mechanism shaping sex chromosomal
evolution. |
Does teplizumab hold promise for diabetes prevention? | Yes, teplizumab is promising for diabetes prevention. | IMPORTANCE OF THE FIELD: Type 1 diabetes mellitus (T1D) is a T-cell mediated
autoimmune disease with selective destruction of beta cells. Immunological
interventions are directed at arresting the loss of beta-cell function with the
promise that this will make it easier for patients to control their glucose
levels.
AREAS COVERED IN THIS REVIEW: This review provides a summary of the preclinical
and clinical research published between 1992 and 2009 using teplizumab and other
anti-CD3 antibodies to arrest the loss of beta-cell function in new onset T1D.
Data from animal and human studies on the probable mechanism of action of
teplizumab are also reviewed.
WHAT THE READER WILL GAIN: A broad perspective on the use of teplizumab in
inducing disease specific tolerance.
TAKE HOME MESSAGE: In Phase I/II randomized control trials, in patients with new
onset T1D, teplizumab slowed the rate of loss of beta-cell function over 2 years
of follow-up. Treated patients had better glycemic control and lower insulin
requirements. Adverse events so far are mild and of limited duration. Phase III
clinical trials are underway to confirm these results and to determine if two
courses of drug have greater efficacy in arresting loss of beta-cell function. OBJECTIVE: To review the pharmacology, pharmacokinetics, safety, and efficacy of
teplizumab and evaluate relevant clinical trial data.
DATA SOURCES: Searches of MEDLINE, International Pharmaceutical Abstracts,
ClinicalTrials.gov, American Diabetes Association scientific posters, and Google
Scholar (1966-May 2012) were conducted using the key words teplizumab, anti-CD3
monoclonal antibody, MGA031, and hOKT3γ1 (Ala-Ala). Searches were limited to
articles published in English.
STUDY SELECTION AND DATA EXTRACTION: Clinical trials evaluating teplizumab for
type 1 diabetes mellitus (T1DM) published in English were selected from the data
sources. All published relevant abstracts were included. References cited in
identified articles were used for additional citations.
DATA SYNTHESIS: T1DM accounts for up to 10% of all cases of diabetes mellitus.
T1DM is characterized as a chronic and progressive autoimmune disease leading to
the destruction of insulin-producing β-cells of the pancreas. Teplizumab is a
humanized Fc-mutated anti-CD3 monoclonal antibody that alters the function of
the T-lymphocytes that mediate the destruction of the insulin-producing β-cells.
While clinical data are limited, both Phase 2 and Phase 3 studies have
demonstrated preserved C-peptide response as a measure of insulin production,
decreased exogenous insulin use, and improved glycemic control following a 12-
to 14-day teplizumab infusion in patients diagnosed with T1DM within the
previous 6 weeks. However, 1 Phase 3 trial failed to find the same benefits in
those diagnosed with T1DM within the previous 12 weeks when a lower cumulative
teplizumab dose was used. Initial studies indicated that teplizumab is well
tolerated, with a self-limiting rash as the most commonly reported adverse
effect.
CONCLUSIONS: Teplizumab is an anti-CD3 human monoclonal antibody with promising
activity in treatment of patients with T1DM. Results from Phase 3 trials are
needed to further determine safety, efficacy, and dosing frequency. AIMS/HYPOTHESIS: Type 1 diabetes results from a chronic autoimmune process
continuing for years after presentation. We tested whether treatment with
teplizumab (a Fc receptor non-binding anti-CD3 monoclonal antibody), after the
new-onset period, affects the decline in C-peptide production in individuals
with type 1 diabetes.
METHODS: In a randomised placebo-controlled trial we treated 58 participants
with type 1 diabetes for 4-12 months with teplizumab or placebo at four academic
centres in the USA. A central randomisation centre used computer generated
tables to allocate treatments. Investigators, patients, and caregivers were
blinded to group assignment. The primary outcome was a comparison of C-peptide
responses to a mixed meal after 1 year. We explored modification of treatment
effects in subgroups of patients.
RESULTS: Thirty-four and 29 subjects were randomized to the drug and placebo
treated groups, respectively. Thirty-one and 27, respectively, were analysed.
Although the primary outcome analysis showed a 21.7% higher C-peptide response
in the teplizumab-treated group (0.45 vs 0.371; difference, 0.059 [95% CI 0.006,
0.115] nmol/l) (p = 0.03), when corrected for baseline imbalances in HbA(1c)
levels, the C-peptide levels in the teplizumab-treated group were 17.7% higher
(0.44 vs 0.378; difference, 0.049 [95% CI 0, 0.108] nmol/l, p = 0.09). A greater
proportion of placebo-treated participants lost detectable C-peptide responses
at 12 months (p = 0.03). The teplizumab group required less exogenous insulin
(p < 0.001) but treatment differences in HbA(1c) levels were not observed.
Teplizumab was well tolerated. A subgroup analysis showed that treatment
benefits were larger in younger individuals and those with HbA(1c) <6.5% at
entry. Clinical responders to teplizumab had an increase in circulating CD8
central memory cells 2 months after enrolment compared with non-responders.
CONCLUSIONS/INTERPRETATIONS: This study suggests that deterioration in insulin
secretion may be affected by immune therapy with teplizumab after the new-onset
period but the magnitude of the effect is less than during the new-onset period.
Our studies identify characteristics of patients most likely to respond to this
immune therapy.
TRIAL REGISTRATION: ClinicalTrials.gov NCT00378508
FUNDING: This work was supported by grants 2007-502, 2007-1059 and 2006-351 from
the JDRF and grants R01 DK057846, P30 DK20495, UL1 RR024139, UL1RR025780, UL1
RR024131 and UL1 RR024134 from the NIH. Since type 1 diabetes is an immunologically mediated disease, immune
intervention should alter the natural history of the disease. This article
reviews prevention studies undertaken either prior to any evidence of
autoimmunity (primary prevention) or after the development of islet
autoantibodies (secondary prevention). Most immune intervention studies have
been conducted in recent-onset type 1 diabetes (tertiary prevention), and these
are not reviewed herein. The goal of primary and secondary intervention is to
arrest the immune process and thus prevent or delay clinical disease. Primary
prevention studies have been conducted in infants with high genetic risk.
Interventions tested include several dietary manipulations, including infant
formulas free of either cow's milk or of bovine insulin, infant formula
supplemented with the omega-3-fatty acid docosahexaenoic acid, delayed
introduction of gluten-containing foods, and vitamin D supplementation.
Secondary prevention studies have been conducted in both children and adults
with diabetes autoantibodies. Interventions tested include nicotinamide, insulin
injections, oral insulin, nasal insulin, glutamic acid decarboxylase, and
cyclosporine. Underway are secondary prevention studies with teplizumab and with
abatacept. INTRODUCTION: Type 1 diabetes is an organ-specific autoimmune disease,
characterized by selective destruction of insulin-producing pancreatic β-cells
by T-cell-mediated inflammation. Beginning with studies of cyclosporin A in the
1980s, but with more activity in the past decade, there have been a number of
clinical trials to test whether immunotherapies can arrest the decline in
C-peptide, which is associated with progression of type 1 diabetes leading to
the metabolic instability that characterizes the disease. One of the most
promising agents, teplizumab , is an FcR-nonbinding anti-CD3 monoclonal antibody
that has been tested in Phase II - III clinical trials and was shown to preserve
the C-peptide levels and reduce the need for exogenous insulin.
AREAS COVERED: In this review, we discuss the recent update on clinical data
obtained from trials of teplizumab in type 1 diabetes, the drug's postulated
mechanism of action and the identification of responders to therapy. We
highlight the results of recent trials as well as the lessons that have been
learned from the clinical trials involving selection of end points and the
inclusion of diverse study populations.
EXPERT OPINION: Teplizumab has been shown to preserve β cell function in
patients; however, it does not represent a 'cure' for patients, and its efficacy
does entail a significant advance in arresting the progression of the disease
toward complete insulin deficiency and reliance on exogenous insulin. AIMS/HYPOTHESIS: The long-term effects of successful immune therapies for
treatment of type 1 diabetes have not been well studied. The
Autoimmunity-Blocking Antibody for Tolerance (AbATE) trial evaluated teplizumab,
an Fc receptor non-binding humanised anti-CD3 monoclonal antibody in individuals
with new-onset type 1 diabetes, and ended in 2011. Clinical drug-treated
responders showed an increased frequency of 'partially exhausted' CD8+ T cells.
We studied the clinical, immunological and metabolic status of participants
after an average follow-up of 7 years.
METHODS: Participants with detectable C-peptide at year 2 of AbATE returned for
follow-up. C-peptide responses were assessed by 4 h mixed-meal tolerance test.
Autoantibodies and HbA1c levels were measured and average daily insulin use was
obtained from patient logs. Peripheral blood mononuclear cells were analysed by
flow cytometry and cytokine release.
RESULTS: Fifty-six per cent of the original participants returned. Three of the
original control group who did not return had lost all detectable C-peptide by
the end of the 2 year trial. The C-peptide responses to a mixed-meal tolerance
test were similar overall in the drug vs control group of participants but were
significantly improved, with less loss of C-peptide, in drug-treated responders
identified at 1 year. However, the improvements in C-peptide response were not
associated with lower HbA1c levels or insulin use. Drug-treated responders
showed a significantly increased frequency of programmed cell death protein
1-positive central memory and anergic CD8+ T cells at follow-up.
CONCLUSIONS/INTERPRETATION: These findings suggest there is reduced decline in
C-peptide and persistent immunological responses up to 7 years after diagnosis
of diabetes in individuals who respond to teplizumab.
TRIAL REGISTRATION: ClinicalTrials.gov NCT02067923; the protocol is available at
www.immunetolerance.org (ITN027AI). Type 1 diabetes (T1D) is an autoimmune disease characterized by an insulin
deficiency. Ever since the discovery of insulin almost 100 years ago, patients
with T1D have relied on multiple daily insulin injections to survive an
otherwise deadly disease. Despite decades of research and clinical trials, no
treatment exists yet to prevent or cure T1D. A recent prevention trial using the
anti-CD3 antibody teplizumab in individuals at a high risk of developing T1D has
provided the first piece of evidence that a safe and transient intervention may
be able to delay disease. In this Perspective, we review the 40-year long
history of anti-CD3 and discuss how this antibody became a candidate for the
treatment of autoimmune diabetes. The path that leads to its use in this latest
clinical trial for T1D has been winding and strewn with setbacks. The molecular
actions of the anti-CD3 antibody that target T lymphocytes are well-understood,
but its systemic effect on immune function has proven more difficult to unravel.
Moreover, preclinical data suggested that the utility of anti-CD3 for the
prevention of T1D may be limited. However, the latest clinical data are
encouraging and exemplify how a basic discovery can, decades later and with much
perseverance, become a promising therapeutic candidate. Over several decades, studies have described the progression of autoimmune
diabetes, from the first appearance of autoantibodies until, and after, the
diagnosis of clinical disease with hyperglycaemia and insulin dependence.
Despite the improved management of type 1 diabetes with exogenous insulin, most
patients do not meet clinical glycaemic goals, and diabetes remains an important
medical problem that affects children and adults. Clinical and preclinical
studies have suggested strategies to prevent the diagnosis of type 1 diabetes in
people at risk, but the outcomes of previous clinical trials have not met their
primary endpoints of disease prevention or delay. The results from the TN-10
teplizumab prevention trial show that the diagnosis of type 1 diabetes can be
delayed by treatment with a FcR non-binding monoclonal antibody to CD3 in people
at high risk for disease. This Series paper discusses how this clinical
achievement raises new questions about for whom, and when, immunological
strategies might be developed to prevent type 1 diabetes, and how to achieve
this goal. |
What is another name for acid sphingomyelinase deficiency (ASMD)? | Acid sphingomyelinase deficiency(ASMD) is also known as Niemann-Pick disease type A and type B. | Niemann-Pick disease (types A and B), or acid sphingomyelinase deficiency, is an
inherited deficiency of acid sphingomyelinase, resulting in intralysosomal
accumulation of sphingomyelin in cells throughout the body, particularly within
those of the reticuloendothelial system. These cellular changes result in
hepatosplenomegaly and pulmonary infiltrates in humans. A knockout mouse model
mimics many elements of human ASMD and is useful for studying disease
histopathology. However, traditional formalin-fixation and paraffin embedding of
ASMD tissues dissolves sphingomyelin, resulting in tissues with a foamy cell
appearance, making quantitative analysis of the substrate difficult. To optimize
substrate fixation and staining, a modified osmium tetroxide and potassium
dichromate postfixation method was developed to preserve sphingomyelin in
epon-araldite embedded tissue and pulmonary cytology specimens. After
processing, semi-thin sections were incubated with tannic acid solution followed
by staining with toluidine blue/borax. This modified method provides excellent
preservation and staining contrast of sphingomyelin with other cell structures.
The resulting high-resolution light microscopy sections permit digital
quantification of sphingomyelin in light microscopic fields. A lysenin affinity
stain for sphingomyelin was also developed for use on these semi-thin epon
sections. Finally, ultrathin serial sections can be cut from these same tissue
blocks and stained for ultrastructural examination by electron microscopy. BACKGROUND: Acid sphingomyelinase deficiency (ASMD), [Niemann-Pick Disease Types
A and B (NPD A and B)], is an inherited metabolic disorder resulting from
deficiency of the lysosomal enzyme acid sphingomyelinase. Accumulation of
sphingomyelin in hepatocytes, reticuloendothelial cells, and in some cases
neurons, results in a progressive multisystem disease that encompasses a broad
clinical spectrum of neurological and visceral involvement, including: infantile
neurovisceral ASMD (NPD A) that is uniformly fatal by 3years of age; chronic
neurovisceral ASMD (intermediate NPD A/B; NPD B variant) that has later symptom
onset and slower neurological and visceral disease progression; and chronic
visceral ASMD (NPD B) that lacks neurological symptoms but has significant
disease-related morbidities in multiple organ systems. The purpose of this study
was to characterize disease-related morbidities and causes of death in patients
with the chronic visceral and chronic neurovisceral forms of ASMD.
METHODS: Data for 85 patients who had died or received liver transplant were
collected by treating physicians (n=27), or abstracted from previously published
case studies (n=58). Ages at symptom onset, diagnosis, and death; cause of
death; organ involvement, and morbidity were analyzed.
RESULTS: Common disease-related morbidities included splenomegaly (96.6%),
hepatomegaly (91.4%), liver dysfunction (82.6%), and pulmonary disease (75.0%).
The overall leading causes of death were respiratory failure and liver failure
(27.7% each) irrespective of age. For patients with chronic neurovisceral ASMD
(31.8%), progression of neurodegenerative disease was a leading cause of death
along with respiratory disease (both 23.1%) and liver disease (19.2%). Patients
with chronic neurovisceral disease died at younger ages than those with chronic
visceral disease (median age at death 8 vs. 23.5years).
CONCLUSIONS: The analysis emphasizes that treatment goals for patients with
chronic visceral and chronic neurovisceral ASMD should include reducing
splenomegaly and improving liver function and respiratory status, with the
ultimate goal of decreasing serious morbidity and mortality. Acid sphingomyelinase deficiency (ASMD; Niemann-Pick disease type A and B) is a
lysosomal storage disorder characterized by abnormal intracellular sphingomyelin
(SM) accumulation. Prominent liver involvement results in hepatomegaly,
fibrosis/cirrhosis, abnormal liver chemistries, and a proatherogenic lipid
profile. Olipudase alfa (recombit human ASM) is in clinical development as an
investigational enzyme replacement therapy for the non-neurological
manifestations of ASMD. In a phase 1b study conducted to evaluate the safety and
tolerability of within-patient dose escalation with olipudase alfa, measurement
of SM levels in liver biopsies was used as a pharmacodynamic biomarker of
substrate burden. Five adult patients with non neuronopathic ASMD received
escalating doses of olipudase alfa every 2 weeks for 26 weeks. Liver biopsies
obtained at baseline and 26 weeks after treatment were evaluated for SM storage
by histomorphometric analysis, biochemistry, and electron microscopy. Biopsies
were also assessed for inflammation and fibrosis, and for the association of SM
levels with liver volume, liver function tests, and lipid profiles. At baseline,
SM storage present in Kupffer cells and hepatocytes ranged from 9.8% to 53.8% of
the microscopic field. After 26 weeks of treatment, statistically significant
reductions in SM (P<0.0001) measured by morphometry were seen in 4 patients with
evaluable liver biopsies. The 26-week biopsy of the fifth patient was
insufficient for morphometric quantitation. Posttreatment SM levels ranged from
1.2% to 9.5% of the microscopic field, corresponding to an 84% to 92% relative
reduction from baseline. Improvements in liver volume, liver function tests, and
lipid profiles were also observed. This study illustrates the utility of SM
assessment by liver biopsy as a pharmacodynamic biomarker of disease burden in
these patients. Acid sphingomyelinase deficiency (ASMD), a rare lysosomal storage disease, is an
autosomal recessive genetic disorder caused by different SMPD1 mutations.
Historically, ASMD has been classified as Niemann-Pick disease (NPD) types A
(NPD A) and B (NPD B). NPD A is associated with a uniformly devastating disease
course, with rapidly progressing psychomotor degeneration, leading to death
typically by the age of 3 years, most often from respiratory failure. In
contrast, the clinical phenotype and life expectancy of patients with NPD B may
vary widely. Almost all patients have hepatosplenomegaly and an atherogenic
lipid profile, and most patients have interstitial lung disease with progressive
impairment of pulmonary function and hematologic abnormalities including
cytopenias. Other common clinical manifestations include liver dysfunction,
heart disease, skeletal abnormalities and growth delays. Some patients with ASMD
who survive beyond early childhood have intermediate phenotypes (variant NPD B)
characterized by combinations of non-neurologic and mild to severe neurologic
symptoms. The physical and psychosocial burden of illness in patients with NPD B
is substantial. Common symptoms include shortness of breath, joint or limb pain,
abdominal pain, bleeding and bruising. The disease often leads to chronic
fatigue, limited physical or social activity and difficulties in performing
daily activities or work. Many patients die before or in early adulthood, often
from pneumonia/respiratory failure or liver failure. Available treatments are
limited to symptom management and supportive care. An enzyme replacement therapy
currently in clinical development is expected to be the first treatment
addressing the underlying pathology of the disease. Early diagnosis and
appropriate management are essential for reducing the risk of complications.
While knowledge about ASMD is evolving, more evidence about ASMD and the natural
history across the disease spectrum is needed, to improve disease recognition,
timely diagnosis and appropriate disease management. Author information:
(1)Institute of Inherited Metabolic Disorders, First Faculty of Medicine,
Charles University and General University Hospital, Prague, Czech Republic.
Electronic address: [email protected].
(2)Institute of Inherited Metabolic Disorders, First Faculty of Medicine,
Charles University and General University Hospital, Prague, Czech Republic.
(3)Behavioral Core Facility, Dominick P. Purpura Department of Neuroscience,
Albert Einstein College of Medicine, Bronx, NY, USA.
(4)Department of Genetics, Institute of Psychiatry and Neurology, Warsaw,
Poland.
(5)Department of Pediatrics and Adolescent Medicine, First Faculty of Medicine,
Charles University and General University Hospital, Prague, Czech Republic. INTRODUCTION: Acid sphingomyelinase deficiency (ASMD, also known as Niemann-Pick
Type A and Type B disease) is a rare, inherited metabolic disorder.
Liver-related issues, including cirrhosis and variceal haemorrhage, are a
leading cause of early mortality in individuals with chronic forms of ASMD. Due
to the rarity of this lysosomal storage disorder, there can be a lack of
awareness that adults with chronic ASMD disease are at significant risk of
cirrhosis, portal hypertension, and variceal bleeding. This case highlights an
unusual presentation of recurrent variceal bleeding in an adult with cirrhosis
and portal hypertension due to chronic visceral ASMD.
CASE PRESENTATION: A patient with severe splenomegaly was diagnosed with ASMD at
age of 25. At age 64 they had multiple hospital admissions for hematochezia
(originally diagnosed as ischemic colitis) accompanied by hypotension (blood
pressure 91/45 mmHg), anemia (hemoglobin 8.5g/dL, ref 12-16; INR 1.4, ref ≤1.2),
and mild renal insufficiency (creatinine 1.33mg/dL, ref 0.51-0.95). Colonoscopy
did not reveal a source of bleeding. Computerized tomography scanning imaging
showed diffuse venous collaterals and ascites. Arteriographies during subsequent
episodes of bleeding were negative for active arterial intestinal bleeding.
Recurrent gastrointestinal bleeding was found to originate from a varicose vein
cluster connected to the right iliac vein and the superior mesenteric vein,
located in the submucosa of a small intestinal loop. Multiple varices were
secondary to portal hypertension in the context of cirrhosis. The patient died
from recurrent variceal bleeding that exacerbated liver failure worsened by
pneumonia and hypovolemic and septic shock.
CONCLUSIONS: The variceal bleeding in this patient was atypical in that it
originated from venous collaterals bleeding into the small intestine rather than
the more typical gastroesophageal varices observed in ASMD. With long standing
liver dysfunction and gradual development of portal hypertension, intestinal
varices rather than occult intestinal bleeding due to ischemia should be
considered in ASMD patients presenting with either hematochezia or hematemesis. |
What rare disease is associated with a mutation in the GPC6 gene on chromosome 13? | The proband had normal molecular analysis of the glypican 6 gene (GPC6), which was recently reported as a candidate for autosomal recessive omodysplasia | Glypicans are a family of glycosylphosphatidylinositol (GPI)-anchored,
membrane-bound heparan sulfate (HS) proteoglycans. Their biological roles are
only partly understood, although it is assumed that they modulate the activity
of HS-binding growth factors. The involvement of glypicans in developmental
morphogenesis and growth regulation has been highlighted by Drosophila mutants
and by a human overgrowth syndrome with multiple malformations caused by
glypican 3 mutations (Simpson-Golabi-Behmel syndrome). We now report that
autosomal-recessive omodysplasia, a genetic condition characterized by
short-limbed short stature, craniofacial dysmorphism, and variable developmental
delay, maps to chromosome 13 (13q31.1-q32.2) and is caused by point mutations or
by larger genomic rearrangements in glypican 6 (GPC6). All mutations cause
truncation of the GPC6 protein and abolish both the HS-binding site and the
GPI-bearing membrane-associated domain, and thus loss of function is predicted.
Expression studies in microdissected mouse growth plate revealed expression of
Gpc6 in proliferative chondrocytes. Thus, GPC6 seems to have a previously
unsuspected role in endochondral ossification and skeletal growth, and its
functional abrogation results in a short-limb phenotype. We report on the natural history of a female with domit omodysplasia, a rare
osteochondrodysplasia with short stature, rhizomelia of the extremities (upper
extremities more affected), and short first metacarpals. The proband had normal
molecular analysis of the glypican 6 gene (GPC6), which was recently reported as
a candidate for autosomal recessive omodysplasia. The findings in this patient
were compared to other known and suspected cases of autosomal domit
omodysplasia. Mild rhizomelic shortening of the lower extremities has not been
previously reported. |
What are 3 symptoms of Waardenburg Syndrome? | Waardenburg syndrome is a rare genetic disorder of neural crest cells (NCC) characterized by congenital sensorineural hearing loss, dystopia canthorum, and abnormal iris pigmentation. | Author information:
(1)Department of Otolaryngology-Head and Neck Surgery, Xiangya Hospital, Central
south University, Changsha 410008, People's Republic of China; Key Laboratory of
Otolaryngology Major Disease Research of Hu Province, Changsha, 410008,
People's Republic of China.
(2)State Key Laboratory of Medical Genetics, Central South University, Changsha
410078, People's Republic of China.
(3)State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun
Yat-Sen University, Guangzhou 510060, People's Republic of China.
(4)Department of Otolaryngology-Head and Neck Surgery, Xiangya Hospital, Central
south University, Changsha 410008, People's Republic of China; Key Laboratory of
Otolaryngology Major Disease Research of Hu Province, Changsha, 410008,
People's Republic of China; State Key Laboratory of Medical Genetics, Central
South University, Changsha 410078, People's Republic of China. Electronic
address: [email protected].
(5)Department of Otolaryngology-Head and Neck Surgery, Xiangya Hospital, Central
south University, Changsha 410008, People's Republic of China; Key Laboratory of
Otolaryngology Major Disease Research of Hu Province, Changsha, 410008,
People's Republic of China. Electronic address: [email protected]. Waardenburg Syndrome (WS) is a condition characterized by pigmentary changes of
the hair or skin, hearing loss, heterochromia iridis, and dystopia canthorum.
There are four main types of WS, which can be commonly caused by mutations in
the PAX3, MITF, EDNRB, EDN3, SNAI2, or SOX10 genes. Herein, we present a patient
with Waardenburg Syndrome type 2 with no findings of mutations in the commonly
associated genes. |
Does ProSavin use an adenoviral vector? | No, ProSavin is a lentiviral vector based gene therapy. | Parkinson's disease is typically treated with oral dopamine replacement
therapies. However, long-term use is complicated by motor fluctuations from
intermittent stimulation of dopamine receptors and off-target effects. ProSavin,
a lentiviral vector based gene therapy that delivers local and continuous
dopamine, was previously shown to be well tolerated in a Phase I/II
first-in-human study, with significant improvements in motor behavior from
baseline at 1 year. Here, patients with Parkinson's disease from the open-label
trial were followed up in the long term to assess the safety and efficacy of
ProSavin after bilateral injection into the putamen. Fifteen patients who were
previously treated with ProSavin have been followed for up to 5 years, with some
having been seen for 8 years. Eight patients received deep brain stimulation at
different time points, and their subsequent assessments continued to assess
safety. Ninety-six drug-related adverse events were reported (87 mild, 6
moderate, 3 severe) of which more than half occurred in the first year. The most
common drug-related events were dyskinesias (33 events, 11 patients) and on-off
phenomena (22 events, 11 patients). A significant improvement in the defined
"off" Unified Parkinson's Disease Rating Scale part III motor scores, compared
to baseline, was seen at 2 years (mean score 29 · 2 vs. 38 · 4, n = 14,
p < 0.05) and at 4 years in 8/15 patients. ProSavin continued to be safe and
well tolerated in patients with Parkinson's disease. Moderate improvements in
motor behavior over baseline continued to be reported in the majority of
patients who could still be evaluated up to 5 years of follow-up. |
Does radiation for tinea capitis increases brain tumor risk? | Yes, radiation therapy for tinea capitis is associated with increased risk of meningiomas and gliomas. | Three patients are described in whom irradiation of 2750 rad or more was used in
the management of primary brain tumours, and 21 years or more later a second
brain tumour of a different type occurred. One of the new tumours was a
meningioma and the other two were cerebral astrocytomas. There is evidence to
show that moderate doses of ionising radiations given in childhood for tinea
capitis are associated with a late risk of developing a meningioma. Higher doses
of radiation used for tumours in childhood are followed also by a late hazard of
meningioma. There is insufficient evidence to implicate ionising radiations in
the aetiology of gliomas. The oncogenic hazards of radiotherapy to the brain do
not outweigh its therapeutic value in brain tumour. A 39-year-old male developed primary brain lymphoma 33 years after receiving
scalp irradiation for tinea capitis. This is the first reported association
between cranial irradiation during childhood and subsequent development of
primary brain lymphoma. We have analyzed 60 cases of intra-axial brain tumors associated with antecedent
radiation therapy. These include four new cases. The patients had originally
received radiation therapy for three reasons: (a) cranial irradiation for acute
lymphoblastic leukemia (ALL), (b) definitive treatment of CNS neoplasia, and (c)
treatment of benign disease (mostly cutaneous infections). The number of cases
reported during the past decade has greatly increased as compared to previous
years. Forty-six of the 60 intra-axial tumors have been reported since 1978. The
relative risk of induction of an intra-axial brain tumor by radiation therapy is
estimated to be more than 100, as compared to individuals who have not had head
irradiation. The risk of developing a tumor of the nervous system in humans is analysed in
several studies of populations, exposed to ionising radiation for medical
reasons, or exposed to military or occupational radiation. The main data come
from series of patients who underwent radiotherapy during childhood: a high
incidence of tumors of the nervous system is found after irradiation of one to a
few grays as treatment of a benign disease (especially tinea capitis), as well
as after irradiation at higher doses of a few tens of grays for the treatment of
cancer (in particular cerebral irradiation in acute lymphoblastic leukaemia).
The type of radiation-induced tumors is variable, but meningioma is more
frequent after low doses and glioma and sarcoma after higher doses used in the
treatment of neoplastic diseases. A dose-effect relationship appeared between
the risk of tumor of the nervous system and the radiation dose. The risk was
higher when radiation was delivered at a younger age. Much less data are
available after radiotherapy in the adulthood, but an increased risk of cerebral
tumor appears in the series of ankylosing spondylitis patients. As for the
exposures to radiodiagnosis exams, the main problem is the risk of cerebral
tumor in children whose mother has undergone abdominal or pelvic X-rays during
pregcy. No risk of neurologic tumor was found in the A-bomb survivors
irradiated at Hiroshima and Nagasaki. Occupational exposure to ionising
radiation has been incriminated in the first radiologists exposed to high doses.
In nuclear industry workers, the results of epidemiological studies are
contradictory and at the present time it is not possible to link their
radiologic exposure with a risk of tumor of the nervous system. In populations
living near nuclear plants, mortality due to tumors of the nervous system was
not increased. Although meningiomas are known to be induced by low doses of cranial
irradiation, such as those given to treat tinea capitis, little experience has
been reported on the induction of meningiomas by high-dose cranial irradiation.
The authors describe a series of 10 patients with meningiomas and a previous
history of high-dose radiation therapy, usually given for a primary brain tumor.
Of the 10 patients, eight were female, three had multiple meningiomas, and the
majority had other stigmata of previous radiation therapy. Eight meningiomas
were examined pathologically and one-half were classified as either aggressive
or atypical, or were noted to have a high bromodeoxyuridine labeling index. The
average time from radiation therapy to diagnosis of a meningioma was 24 years
(range 5 to 40 years), a shorter interval than that previously reported for
meningiomas induced by lower doses of irradiation. Within this series, patient
age at irradiation was significantly correlated with tumor latency; individuals
who were younger at the time of radiation therapy had a shorter time to
meningioma formation. The latency of meningioma formation is therefore
influenced by both the radiation dose and the age of the patient at irradiation. This is a two-year progress report on a life span dose-response study of brain
tumor risk at moderate to high doses of energetic protons. It was initiated
because a joint NASA/USAF life span study of rhesus monkeys that were irradiated
with 55-MeV protons (average surface dose, 3.5 Gy) indicated that the incidence
of brain tumors per unit surface absorbed dose was over 19 times that of the
human tinea capitis patients whose heads were exposed to 100 kv x-rays.
Examination of those rats that died in the two-year interval after irradiation
of the head revealed a linear dose-response for total head and neck tumor
incidence in the dose range of 0-8.5 Gy. The exposed rats had a greater
incidence of pituitary chromophobe adenomas, epithelial and mesothelial cell
tumors than the unexposed controls but the excessive occurrence of maligt
gliomas that was observed in the monkeys was absent in the rats. The estimated
dose required to double the number of all types of head and neck tumors was 5.2
Gy. The highest dose, 18 Gy, resulted in high mortality due to obstructive
squamous metaplasia at less than 50 weeks, prompting a new study of the relative
biological effectiveness of high energy protons in producing this lesion. High dose radiation-induced meningiomas are a rare, severe and late complication
of craniospinal radiotherapy for brain tumors. Radiation-induced meningiomas
are, according to the literature, several times more frequent than radiogenic
gliomas and sarcomas. It is suggested that every new case of radiogenic
meningioma has to be reported to elucidate this particular pathologic entity
with its many grey areas. In addition to high dose radiation-induced
meningiomas, intracranial meningiomas were observed in patients who underwent
low-dose radiation for tinea capitis in childhood, applied en mass to immigrants
coming to Israel from the North Africa and the Middle East during the 1950.
Authors summarize the data on radiogenic meningiomas from the literature and, as
the previous radiotherapy may confer a low, but life-long risk for meningioma
occurrence, they suggest that surveillance MRI after high dose cerebrospinal
radiotherapy should be extended to several (3-5) decades after radiotherapy. Ionizing radiation is an established risk factor for brain tumors, yet
quantitative information on the long-term risk of different types of brain
tumors is sparse. Our aims were to assess the risk of radiation-induced
maligt brain tumors and benign meningiomas after childhood exposure and to
investigate the role of potential modifiers of that risk. The study population
included 10,834 individuals who were treated for tinea capitis with X rays in
the 1950s and two matched nonirradiated groups, comprising population and
sibling comparison groups. The mean estimated radiation dose to the brain was
1.5 Gy. Survival analysis using Poisson regression was performed to estimate the
excess relative and absolute risks (ERR, EAR) for brain tumors. After a median
follow-up of 40 years, an ERR/Gy of 4.63 and 1.98 (95% CI = 2.43-9.12 and
0.73-4.69) and an EAR/Gy per 10(4) PY of 0.48 and 0.31 (95% CI = 0.28-0.73 and
0.12-0.53) were observed for benign meningiomas and maligt brain tumors,
respectively. The risk of both types of tumors was positively associated with
dose. The estimated ERR/Gy for maligt brain tumors decreased with increasing
age at irradiation from 3.56 to 0.47 (P = 0.037), while no trend with age was
seen for benign meningiomas. The ERR for both types of tumor remains elevated at
30-plus years after exposure. Secondary glioblastoma multiforme (sGBM) can occur after a long latency period
following radiation treatment of various diseases including brain tumors,
leukemia, and more benign disorders like tinea capitis. Outcomes of
radiation-induced sGBM remain poor in both children and adults. We report a case
of a 16-year-old girl with a history of disseminated juvenile pilocytic
astrocytoma treated with chemotherapy and craniospinal radiation 9 years prior
who developed sGBM in the absence of a tumor predisposition syndrome. She
presented with a several-week history of headaches and no acute findings on
computed tomography compared to baseline neuroimaging 3 months prior. Repeat
computed tomography performed just 3 weeks later for worsening headaches
revealed a new large posterior fossa tumor where pathology confirmed the
diagnosis of sGBM. In spite of maximal surgical resection, reirradiation, and
adjuvant chemotherapy, she died 1 year postdiagnosis. Our case highlights the
potential late effects of high-dose cranial radiation, how symptomatology may
precede neuroimaging findings, and the rapid formation of sGBM that mirrors that
of de novo Glioblastoma Multiforme. |
What gene is mutated in Huntington's Disease patients? | Huntington's disease (HD) is a fully penetrant neurodegenerative disease caused by a dominantly inherited CAG trinucleotide repeat expansion in the huntingtin gene HTT encoding the Huntingtin protein on chromosome 4. | Huntington's disease is an inherited disorder caused by expansion of a CAG
trinucleotide repeat in the IT15 gene, which leads to expansion of a
polyglutamine tract within the protein called huntingtin. Despite the
characterization of the IT15 gene and the mutation involved in the disease, the
normal function of huntingtin and the effects of the mutation on its function
and on its neuronal location remain unknown. To study whether mutated huntingtin
has the same neuronal distribution and intracellular location as normal
huntingtin, we analyzed immunohistochemically both forms of this protein in the
brain of 5 controls and 5 patients with Huntington's disease. We show that the
distribution of mutated huntingtin is, like that of the normal form,
heterogeneous throughout the brain, but is not limited to vulnerable neurons in
Huntington's disease, supporting the hypothesis that the presence of the mutated
huntingtin in a neuron is not in itself sufficient to lead to neuronal death.
Moreover, whereas normal huntingtin is detected in some neuronal perikarya,
nerve fibers, and nerve endings, the mutated form is observed in some neuronal
perikarya and proximal nerve processes but is not detectable in nerve endings.
Our results suggest that the expression or processing of the mutated huntingtin
in perikarya and nerve endings differs quantitatively or qualitatively from the
expression of the normal form in the same neuronal compartments. Huntington's disease (HD) is a late onset, incurable, autosomal
domitly-inherited, progressive neuropsychiatric disease, characterised by
chorea, changes in personality, mood and behaviour, and dementia. Huntington's
disease is a clinical diagnosis. The advent of DNA diagnosis has made
predictive, prenatal and preimplantation testing possible for at-risk persons or
asymptomatic carriers. The prevalence is estimated to be 3-10/100,000 among
individuals of European descent; HD is less common in other ethnic groups.
Huntington's disease is caused by an expanded trinucleotide CAG repeat in the HD
gene on chromosome 4. The gene encodes for the protein huntingtin, with an as
yet unknown function. The mutated huntingtin has an elongated stretch of
glutamines which leads to a gain of function such as overactivity,
excitotoxicity, or to interactions with other proteins. Huntington's disease (HD) is a devastating neurodegenerative disorder that
occurs in patients with a mutation in the huntingtin or IT15 gene. Patients are
plagued by early cognitive signs, motor deficits, and psychiatric disturbances.
Symptoms are attributed to cell death in the striatum and disruption of
cortical-striatal circuitry. Mechanisms of cell death are unclear, but processes
involving mitochondrial abnormalities, excitotoxicity, and abnormal protein
degradation have been implicated. Many factors likely contribute to neuron death
and dysfunction, and this has made it difficult to systematically address the
pathology in HD. Pharmaceutical therapies are commonly used in patients to treat
disease symptoms. These have limited benefit and do not address the inexorable
disease progression. Several neuroprotective therapies are being evaluated in
animal models of HD as well as in clinical trials. Similarly, cell replacement
strategies such as fetal transplantation have been used in the clinic with
minimal success, making future cell replacement strategies such as stem cell
therapy uncertain. This review describes the disease pathology in HD and
addresses many of the past and emerging therapeutic strategies. A mutation in the huntingtin (Htt) gene produces mutant Htt and Huntington's
disease (HD), a neurodegenerative disorder. HD patients have oxidative damage in
the brain, but the causes are unclear. Compared with controls, we found brain
levels of NADPH oxidase (NOX) activity, which produces reactive oxygen species
(ROS), elevated in human HD postmortem cortex and striatum and highest in
striatum of presymptomatic individuals. Synaptosome fractions from cortex and
striatum of HD(140Q/140Q) mice had elevated NOX activity at 3 months of age and
a further rise at 6 and 12 months compared with synaptosomes of age-matched
wild-type (WT) mice. High NOX activity in primary cortical and striatal neurons
of HD(140Q/140Q) mice correlated with more ROS and neurite swellings. These
features and neuronal cell death were markedly reduced by treatment with NOX
inhibitors such as diphenyleneiodonium (DPI), apocynin (APO) and VAS2870. The
rise in ROS levels in mitochondria of HD(140Q/140Q) neurons followed the rise in
NOX activity and inhibiting only mitochondrial ROS was not neuroprotective.
Mutant Htt colocalized at plasma membrane lipid rafts with gp91-phox, a
catalytic subunit for the NOX2 isoform. Assembly of NOX2 components at lipid
rafts requires activation of Rac1 which was also elevated in HD(140Q/140Q)
neurons. HD(140Q/140Q) mice bred to gp91-phox knock-out mice had lower NOX
activity in the brain and in primary neurons, and neurons had normal ROS levels
and significantly improved survival. These findings suggest that increased NOX2
activity at lipid rafts is an early and major source of oxidative stress and
cell death in HD(140Q/140Q) neurons. Huntington's disease is an inherited disorder caused by expanded stretch of
consecutive trinucleotides (cytosine-adenosine-guanine, CAG) within the first
exon of the huntingtin (HTT) gene on chromosome 4 (p16.3). The mutated
huntingtin (mHTT) gains toxic function, probably through mechanisms that involve
aberrant interactions in several pathways, causing cytotoxicity. Pathophysiology
of disease involves several tissues; indeed it has been shown that there is a
broad toxic effect of mHTT in the peripheral tissue of patients with HD, not
only in the central nervous system. In this study we compared gene expression
profiles (GEP) of HD fibroblasts and matched controls using microarray
technology. We used RT-PCR to test the consistency of the microarray data and we
found four genes up-regulated in HD patients with respect to control
individuals. The genes appear to be involved in different pathways that have
been shown to be perturbed even in HD models and patients. Although our study is
preliminary and has to be extended to a larger cohort of HD patients and
controls, nevertheless it shows that gene expression profiles seem to be altered
in the fibroblasts of HD patients. Validation of the differential expressions at
the protein level is required to ascertain if this cell type can be considered a
suitable model for the identification of HD biomarkers. Huntington's disorder (HD), caused by mutations of the IT-15 gene, is an
autosomal genetic disease that causes the breakdown of the nerve cells in the
brain. The IT-15 gene encodes the huntingtin (Htt) protein. Htt, along with its
interacting partners, are involved in maintaining proper communication among
neurons. Our work is based on the interaction behavior between Htt (in three
polyglutamine (polyQ) states that is Htt 0Q, 17Q and 36Q) and SH3GL3 interacting
protein by using computational methods. We used the HADDOCK docking platform to
find out the extent of interaction between Htt polyQ models and SH3GL3. The
Htt36Q (mutated) showed higher interaction than Htt17Q (native) with SH3GL3.
Molecular dynamics simulation was performed to uncover the structural
fluctuations of polyQ models and their complexes. RMSD, Rg, SASA, and total
interaction energy graph showed significant results, where as mutant Htt showed
higher fluctuations and flexibility than native Htt. The increase in the length
of polyQ was found to affect the stability, flexibility, and compactness of the
protein and its complex. Our research provided a propitious approach to
understand the consequence of polyglutamination in Htt and its relation with HD. Huntington's disease (HD) is an autosomal domit neurodegenerative disorder of
the central nervous system (CNS) that is defined by a CAG expansion in exon 1 of
the huntingtin gene leading to the production of mutant huntingtin (mHtt). To
date, the disease pathophysiology has been thought to be primarily driven by
cell-autonomous mechanisms, but, here, we demonstrate that fibroblasts derived
from HD patients carrying either 72, 143 and 180 CAG repeats as well as induced
pluripotent stem cells (iPSCs) also characterized by 143 CAG repeats can
transmit protein aggregates to genetically unrelated and healthy host tissue
following implantation into the cerebral ventricles of neonatal mice in a
non-cell-autonomous fashion. Transmitted mHtt aggregates gave rise to both motor
and cognitive impairments, loss of striatal medium spiny neurons, increased
inflammation and gliosis in associated brain regions, thereby recapitulating the
behavioural and pathological phenotypes which characterizes HD. In addition,
both in vitro work using co-cultures of mouse neural stem cells with 143 CAG
fibroblasts and the SH-SY5Y human neuroblastoma cell line as well as in vivo
experiments conducted in newborn wild-type mice suggest that exosomes can cargo
mHtt between cells triggering the manifestation of HD-related behaviour and
pathology. This is the first evidence of human-to-mouse prion-like propagation
of mHtt in the mammalian brain; a finding which will help unravel the molecular
bases of HD pathology as well as to lead to the development of a whole new range
of therapies for neurodegenerative diseases of the CNS. Huntington's disease (HD) is caused by a CAG repeat expansion that encodes a
polyglutamine (polyQ) expansion in the HD disease protein, huntingtin (HTT).
PolyQ expansion promotes misfolding and aggregation of mutant HTT (mHTT) within
neurons. The cellular pathways, including ubiquitin-dependent processes, by
which mHTT is regulated remain incompletely understood. Ube2W is the only
ubiquitin conjugating enzyme (E2) known to ubiquitinate substrates at their
amino (N)-termini, likely favoring substrates with disordered N-termini. By
virtue of its N-terminal polyQ domain, HTT has an intrinsically disordered amino
terminus. In studies employing immortalized cells, primary neurons and a
knock-in (KI) mouse model of HD, we tested the effect of Ube2W deficiency on
mHTT levels, aggregation and neurotoxicity. In cultured cells, deficiency of
Ube2W activity markedly decreases mHTT aggregate formation and increases the
level of soluble monomers, while reducing mHTT-induced cytotoxicity. Consistent
with this result, the absence of Ube2W in HdhQ200 KI mice significantly
increases levels of soluble monomeric mHTT while reducing insoluble oligomeric
species. This study sheds light on the potential function of the non-canonical
ubiquitin-conjugating enzyme, Ube2W, in this polyQ neurodegenerative disease. Huntington's disease (HD) is a neurodegenerative disorder that is caused by
abnormal expansion of CAG repeats in the HTT gene. The transcribed mutant RNA
contains expanded CAG repeats that translate into a mutant huntingtin protein.
This expanded CAG repeat also causes mis-splicing of pre-mRNA due to
sequestration of muscle blind like-1 splicing factor (MBNL1), and thus both of
these elicit the pathogenesis of HD. Targeting the onset as well as progression
of HD by small molecules could be a potent therapeutic approach. We have
screened a set of small molecules to target this transcript and found Myricetin,
a flavonoid, as a lead molecule that interacts with the CAG motif and thus
prevents the translation of mutant huntingtin protein as well as sequestration
of MBNL1. Here, we report the first solution structure of the complex formed
between Myricetin and RNA containing the 5'CAG/3'GAC motif. Myricetin interacts
with this RNA via base stacking at the AA mismatch. Moreover, Myricetin was also
found reducing the proteo-toxicity generated due to the aggregation of
polyglutamine, and further, its supplementation also improves neurobehavioral
deficits in the HD mouse model. Our study provides the structural and
mechanistic basis of Myricetin as an effective therapeutic candidate for HD and
other polyQ related disorders. Two decades ago, researchers identified that a CAG expansion mutation in the
huntingtin (HTT) gene was involved in the pathogenesis of Huntington's disease
(HD). However, since the identification of the HTT gene, there has been no
advance in the development of therapeutic strategies to prevent or reduce the
progression of HD. With the recent advances in stem cell biology and human cell
reprogramming technologies, several novel and exciting pathways have emerged
allowing researchers to enhance their understanding of the pathogenesis of HD,
to identify and screen potential drug targets, and to explore alternative donor
cell sources for cell replacement therapy. This review will discuss the role of
compensatory neurogenesis in the HD brain, the use of stem cell-based therapies
for HD to replace or prevent cell loss, and the recent advance of cell
reprogramming to model and/or treat HD. These new technologies, coupled with
advances in genome editing herald a promising new era for HD research with the
potential to identify a therapeutic strategy to alleviate this debilitating
disorder. Stem Cells 2018;36:146-160. Mutations in the HTT gene, consisting of expansion of CAG triplets, cause the
Huntington's disease (HD), one of the major neurodegenerative disorders.
Formation of aggregates of mutant huntingtin (mHTT, the product of the mutant
HTT gene) leads to cellular dysfunctions, and subsequent neurodegeneration which
manifest clinically as motor abnormalities and cognitive deficits. We recently
used immortalized HEK-293 cells expressing the 1st exon of the mutant HTT gene
as a cellular model of HD, and showed that the stimulation of autophagy by
genistein corrected the mutant phenotype. However, effects of genistein on HD
patient-derived cells remained unknown. In this report, we demonstrated that
genistein also instigated degradation of mHTT in fibroblasts derived from HD
patients. This was assessed as a significant decrease in the levels of HTT in HD
fibroblasts measured by Western-blotting, and the disappearance of intracellular
mHTT aggregates in cells observed by fluorescent microscopy. Fibroblasts derived
from control persons were not affected by genistein treatment. These results
indicate that genistein can improve HD phenotype in patient-derived cells, and
substantiates the need for further studies of this isoflavone as a potential
therapeutic agent. |
List types of cancer where Long intergenic nonprotein coding RNA p53-induced transcript (LINC-PINT) is involved | Long intergenic nonprotein coding RNA p53-induced transcript (LINC-PINT) is involved in the development of pancreatic cancer, glioblastoma and breast cancer. | Long intergenic non-protein coding RNA, p53 induced transcript (Linc-pint) is a
long noncoding RNA (lncRNA) that regulates tumor cell viability and
proliferation. We used qRT-PCR and RNA FISH analysis to evaluate Linc-pint
levels in the plasma and tumor tissues of pancreatic cancer (PCa) patients. Our
data demonstrate that Linc-pint expression is lower in plasma samples from PCa
patients than from healthy individuals, and indicate that plasma Linc-pint
levels are more sensitive than CA19-9 for detecting PCa. Our data also show that
Linc-pint levels are lower in PCa tumors than in adjacent tissues, carcinoma of
the ampulla of Vater (CAV) and cholangiocarcinoma (CCA), and suggest that
Linc-pint could be used for distinguishing the cause of maligt obstructive
jaundice. Low plasma Linc-pint levels correlate with tumor recurrence, while low
tumor Linc-pint levels correlate with poor prognosis for PCa patients after
pancreatectomy. These results thus indicate that low plasma Linc-pint expression
could serve as a minimally invasive biomarker for early PCa detection, and that
low Linc-pint levels in PCa tumors could be used for predicting patient
prognosis. Author information:
(1)Department of Neurosurgery, First Affiliated Hospital of Sun Yat-sen
University, Guangzhou, 510080, Guangdong Province, PR China.
(2)Guangdong Provincial Key Laboratory of Brain Function and Disease, Guangzhou,
510080, Guangdong, PR China.
(3)Department of Neurosurgery, First Affiliated Hospital of Guangxi Medical
University, Nanning, 530000, Guangxi Province, PR China.
(4)Department of Pathology, Fudan University Shanghai Cancer Center, Fudan
University, Shanghai, 200433, PR China.
(5)Department of Spine Surgery, First Affiliated Hospital of Sun Yat-sen
University, Guangzhou, 510080, Guangdong, PR China.
(6)Department of Gastroenterology Surgery, First Affiliated Hospital of Sun
Yat-sen University, Guangzhou, 510080, Guangdong, PR China.
(7)Department of Scientific Research Section, First Affiliated Hospital of Sun
Yat-sen University, Guangzhou, 510080, Guangdong Province, PR China.
(8)Guangzhou Gene Denovo Biotechnology Co. Ltd, Guangzhou, 510006, PR China.
(9)Department of Gastroenterology, University of Texas MD Anderson Cancer
Center, Houston, TX, 77030, USA.
(10)Institute of Life and Health Engineering, College of Life Science and
Technology, Ji University, Guangzhou, 510632, PR China.
(11)Department of Neurosurgery, University of Texas MD Anderson Cancer Center,
Houston, TX, 77030, USA.
(12)Program in Cancer Biology, University of Texas Graduate School of Biomedical
Sciences at Houston, Houston, TX, 77030, USA.
(13)Department of Neurosurgery, First Affiliated Hospital of Sun Yat-sen
University, Guangzhou, 510080, Guangdong Province, PR China.
[email protected].
(14)Guangdong Provincial Key Laboratory of Brain Function and Disease,
Guangzhou, 510080, Guangdong, PR China. [email protected]. |
Is pimavanserin a typical antipsychotic? | No, pimavanserin is an atypical antipsychotic. | Pimavanserin is the first FDA-approved atypical antipsychotic drug indicated for
the treatment of hallucinations and delusions associated with Parkinson's
disease psychosis (PDP). Areas covered: This review focuses on the preclinical
discovery of pimavanserin. It analyzes the pharmacological, behavioral and
molecular mechanisms of pimavanserin and their contribution to the therapeutic
advantages of the drug as reported in published preclinical and clinical
studies, press releases and product labels. Expert opinion: Pimavanserin
exhibits a unique pharmacological profile with omolar affinity at serotonin
5-HT2A and 5-HT2C receptors. Functionally, it acts as a potent inverse agonist
at 5-HT2A receptors, with selectivity over 5-HT2C receptors and no appreciable
activity at other neurotransmitter receptors. Behavioral studies found that
pimavanserin reversed impaired behaviors in animal models predictive of
antipsychotic activity, and with no impairment of motor functions. The drug
exhibits long plasma half-life (57 hours), which support its once/day
administration. A pivotal phase III clinical trial demonstrated significant
improvement in PDP symptoms in patients receiving pimavanserin compared to
placebo-treated patients. The drug also displayed relatively benign safety and
tolerability profiles. Pimavanserin's mechanism of action might contribute to
its unique psychopharmacological properties in the improved treatment of PDP,
and perhaps psychosis in other diseases including schizophrenia and
dementia-related psychosis. |
Can Flotillin be used as exosomal marker? | Yes,
Flotillin 1 is a known exosomal marker protein. | BACKGROUND: Exosomes are released from multiple cell types, contain protein and
RNA species, and have been exploited as a novel reservoir for disease biomarker
discovery. They can transfer information between cells and may cause pathology,
for example, a role for exosomes has been proposed in the pathophysiology of
Alzheimer's disease. Although studied in several biofluids, exosomes have not
been extensively studied in the cerebrospinal fluid (CSF) from humans. The
objective of this study was to determine: 1) whether human CSF contains exosomes
and 2) the variability in exosomal protein content across individuals.
METHODS: CSF was collected from 5 study participants undergoing
thoraco-abdominal aortic aneurysm repair (around 200 - 500 ml per participant)
and low-density membrane vesicles were concentrated by ultracentrifugation. The
presence of exosomes was determined by western blot for marker proteins,
isopycnic centrifugation on a sucrose step gradient and transmission electron
microscopy with immuno-labelling. Whole protein profiling was performed using
Fourier transform ion cyclotron resoce mass spectrometry (FT-ICR).
RESULTS: Flotillin 1 and tumor susceptibility gene 101 (TSG101), two exosomal
marker proteins, were identified in the ultracentrifugation pellet using western
blot. These markers localized to a density consistent with exosomes following
isopycnic centrifugation. Transmission electron microscopy visualized structures
consistent with exosomes in size and appearance that labelled positive for
flotillin 1. Therefore, the pellet that resulted from ultracentrifugation of
human CSF contained exosomes. FT-ICR profiling of this pellet was performed and
84-161 ions were detected per study participant. Around one third of these ions
were only present in a single study participant and one third were detected in
all five. With regard to ion quantity, the median coefficient of variation was
81% for ions detected in two or more samples.
CONCLUSIONS: Exosomes were identified in human CSF and their proteome is a
potential new reservoir for biomarker discovery in neurological disorders such
as Alzheimer's disease. However, techniques used to concentrate exosomes from
CSF need refinement to reduce variability. In this study we used relatively
large starting volumes of human CSF, future studies will focus on exosome
isolation from smaller 'real life' clinical samples; a key challenge in the
development of exosomes as translational tools. Exosomes are ometer-sized vesicles with the function of intercellular
communication, and they are released by various cell types. To reveal the
knowledge about the exosomes from osteoblast, and explore the potential
functions of osteogenesis, we isolated microvesicles from supernatants of mouse
Mc3t3 by ultracentrifugation, characterized exosomes by electron microscopy and
immunoblotting and presented the protein profile by proteomic analysis. The
result demonstrated that microvesicles were between 30 and 100 nm in diameter,
round shape with cup-like concavity and expressed exosomal marker tumor
susceptibility gene (TSG) 101 and flotillin (Flot) 1. We identified a total
number of 1069 proteins among which 786 proteins overlap with ExoCarta database.
Gene Oncology analysis indicated that exosomes mostly derived from plasma
membrane and mainly involved in protein localization and intracellular
signaling. The Ingenuity Pathway Analysis showed pathways are mostly involved in
exosome biogenesis, formation, uptake and osteogenesis. Among the pathways,
eukaryotic initiation factor 2 pathways played an important role in
osteogenesis. Our study identified osteoblast-derived exosomes, unveiled the
content of them, presented potential osteogenesis-related proteins and pathways
and provided a rich proteomics data resource that will be valuable for further
studies of the functions of individual proteins in bone diseases. |
How many genes belong to the KRAB-ZNF family in the human genome? | The KRAB-ZNF family is a multisubunit protein family comprised of 70 co-regulated genes, denoted KLR1-ZNF15, that is represented by multigene families in the human genome. | The Krüppel-associated box-containing zinc finger gene family (KRAB-ZNF) is one
of the largest gene families of transcriptional factors in the human genome.
Although the functions of most of these genes remain to be determined, it is
known that KRAB-mediated transcriptional repression requires a direct
interaction with the KAP1 co-repressor. By mammalian one- or two-hybrid
experiments in HEK293 cells, we compared transcriptional repression activities
of 61 human KRAB-ZNFs. The results showed that six SCAN-KRAB-containing ZNFs are
KAP1-independent transcriptional repressors whose SCAN-KRAB domain is unable to
associate with KAP1 despite retaining transcriptional repression activity.
Transcriptional repression activities of the SCAN-KRAB domain of
KAP1-independent KRAB-ZNFs are not influenced by depletion of endogenous KAP1
levels by small interfering RNA. Although the mechanism by which
KAP1-independent KRAB-ZNFs repress transcriptional activity remains to be
elucidated, it appears that there may be a pathway for transcriptional
repression that does not involve KAP1. These results provide new insight into
the functions of the members of the KRAB-ZNF family. The mechanisms of speciation have been one of the most debated topics in
evolutionary biology. Among all reproductive barriers, postzygotic reproductive
isolation is perhaps the one that has attracted the most attention from
geneticists. Despite remarkable advances in the identification of loci involved
in Drosophila speciation, little is known about the genes, functions, and
biochemical interactions of the molecules underlying hybrid sterility and
inviability in mammals. Here, we discuss the main evolutionary and molecular
features that make transcription factors (TFs), especially the family of zinc
finger proteins with a Krüppel-associated box domain (KRAB-ZNF), strong
candidates to play an important role in postzygotic reproductive isolation.
Motivated by the recent identification of the gene encoding PR domain zinc
finger protein 9 (Prdm9; a KRAB-ZNF gene) as the first hybrid sterility gene
identified in mammals, we further propose integrative approaches to study
KRAB-ZNF genes with the main goal of characterizing the molecular pathways and
interactions involved in hybrid incompatibilities. The KRAB-ZNF (Krüppel-associated box domain zinc finger) gene family is composed
of a large number of highly homologous genes, gene isoforms, and pseudogenes.
The proteins encoded by these genes, whose expression is often tissue-specific,
act as epigenetic suppressors contributing to the addition of repressive
chromatin marks and DNA methylation. Due to its high complexity, the KRAB-ZNF
family has not been studied in sufficient detail, and the involvement of its
members in carcinogenesis remains mostly unexplored. In this study, we aimed to
provide a comprehensive description of cancer-associated KRAB-ZNFs using
publicly available The Cancer Genome Atlas pan-cancer datasets. We analyzed 6727
tumor and normal tissue samples from 16 cancer types. Here, we showed that a
small but distinctive cluster of 16 KRAB-ZNFs is commonly upregulated across
multiple cancer cohorts in comparison to normal samples. We confirmed these
observations in the independent panels of lung and breast cancer cell lines and
tissues. This upregulation was also observed for most of the KRAB-ZNF splicing
variants, whose expression is simultaneously upregulated in tumors compared to
normal tissues. Finally, by analyzing the clinicopathological data for breast
and lung cancers, we demonstrated that the expression of cancer-associated
KRAB-ZNFs correlates with patient survival, tumor histology, and molecular
subtyping. Altogether, our study allowed the identification and characterization
of KRAB-ZNF factors that may have an essential function in cancer biology and
thus potential to become novel oncologic biomarkers and treatment targets. |
Which molecule is targeted by Asciminib? | Asciminib is an orally administered allosteric inhibitor of the BCR-ABL tyrosine kinase. | Chronic myeloid leukaemia (CML) is driven by the activity of the BCR-ABL1 fusion
oncoprotein. ABL1 kinase inhibitors have improved the clinical outcomes for
patients with CML, with over 80% of patients treated with imatinib surviving for
more than 10 years. Second-generation ABL1 kinase inhibitors induce more potent
molecular responses in both previously untreated and imatinib-resistant patients
with CML. Studies in patients with chronic-phase CML have shown that around 50%
of patients who achieve and maintain undetectable BCR-ABL1 transcript levels for
at least 2 years remain disease-free after the withdrawal of treatment. Here we
characterize ABL001 (asciminib), a potent and selective allosteric ABL1
inhibitor that is undergoing clinical development testing in patients with CML
and Philadelphia chromosome-positive (Ph+) acute lymphoblastic leukaemia. In
contrast to catalytic-site ABL1 kinase inhibitors, ABL001 binds to the myristoyl
pocket of ABL1 and induces the formation of an inactive kinase conformation.
ABL001 and second-generation catalytic inhibitors have similar cellular
potencies but distinct patterns of resistance mutations, with genetic barcoding
studies revealing pre-existing clonal populations with no shared resistance
between ABL001 and the catalytic inhibitor nilotinib. Consistent with this
profile, acquired resistance was observed with single-agent therapy in mice;
however, the combination of ABL001 and nilotinib led to complete disease control
and eradicated CML xenograft tumours without recurrence after the cessation of
treatment. Chronic myeloid leukemia (CML) is characterized by a pathognomonic chromosomal
translocation, which leads to the fusion of breakpoint cluster region (BCR) and
Abelson leukemia virus 1 (ABL1) genes, generating an oncoprotein with
deregulated tyrosine kinase activity. Areas covered: In the last two decades,
BCR/ABL1 kinase has become the molecular target for tyrosine kinase inhibitors
(TKIs), a class of drugs that impressively improved overall survival. Despite
these results, a proportion of patients experiences resistance to TKIs and need
to change treatment. Furthermore, TKIs are unable to eradicate leukemic stem
cells, allowing the persistence of neoplastic clones. Therefore, there is still
clinical need for new agents to overcome common resistance mechanisms to
available drugs. This review explores the horizon of drugs actually under
investigation for CML patients resistant to conventional treatment. Expert
commentary: Radotinib is an ATP-competitive TKI that showed significant activity
also in front-line setting and could find employment indications in CML.
Asciminib, an allosteric ABL1 inhibitor, could demonstrate a higher capacity in
overcoming common TKIs resistant mutations, including T315I, but clinical
findings are needed. CML stem cell target will probably require new therapeutic
strategies: combinations of several compounds acting with different mechanisms
of action are actually under investigation. Asciminib (previously ABL001), which binds the myristate-binding pocket of the
Bcr-Abl kinase domain, is in phase I clinical trials as monotherapy and in
combination with imatinib, nilotinib and dasatinib for the treatment of patients
with refractory CML or Ph+ ALL. Asciminib sensitivity was evaluated in asciminib
naïve BCR-ABL1+ cell lines K562 (negligible ABCB1/ABCG2 expression), K562-Dox
(ABCB1-overexpressing through doxorubicin exposure) and K562-ABCG2 (ABCG2
overexpression via transduction) with results demonstrating asciminib efflux by
both ABCB1 and ABCG2 transporters. K562-Dox and K562-ABCG2 cells demonstrated
increased LD50asciminib vs K562 control cells: 256 and 299 nM respectively vs 24
nM, p < 0.001. Sensitivity was completely restored with specific inhibitors
cyclosporine (ABCB1) and Ko143 (ABCG2): K562-Dox LD50asciminib+cyclosporine = 13
nM, K562-ABCG2 LD50asciminib+Ko143 = 15 nM (p < 0.001). When asciminib
resistance was modelled in vitro, ABCB1 and ABCG2 overexpression was integral in
the development of asciminib resistance. In K562 asciminib-resistant cells,
ABCG2 expression increased prior to BCR-ABL1 overexpression and remained high
(up to 7.6-fold greater levels in resistant vs control cells, p < 0.001).
K562-Dox asciminib-resistant cells had increased ABCB1 expression (2.1-fold vs
control cells p = 0.0033). KU812 asciminib-resistant cells overexpressed ABCB1
(5.4-fold increase, p < 0.001) and ABCG2 (6-fold increase, p < 0.001) before
emergence of a novel myristate-binding pocket mutation (F497L). In all three
cell lines, asciminib resistance was reversible upon chemical inhibition of
ABCB1, ABCG2 or both (p < 0.001). When K562 asciminib-resistant cells were
treated with asciminib in combination with clinically achievable doses of either
imatinib or nilotinib, reversal of the resistance phenotype was also observed (p
< 0.01). Overexpression of efflux transporters will likely be an important
pathway for asciminib resistance in the clinical setting. Given the lack of
evidence for ABCG2-mediated transport of nilotinib or imatinib at clinically
relevant concentrations, our data provide an additional rationale for using
asciminib in combination with either TKI. Asciminib (ABL001) is an orally administered allosteric inhibitor of the BCR-ABL
tyrosine kinase. The current study evaluated the relative bioavailability of its
2 tablet variants, AAA and NXA, compared with the capsule CSF and assessed the
impact of food in healthy participants in a 2-arm, randomized, open-label, 4-way
crossover design. The primary pharmacokinetic parameters analyzed were area
under the plasma concentration-time curve (AUC) from time 0 to the time of last
measurable concentration (AUClast ), AUC from time 0 to infinity (AUCinf ), and
peak concentration (Cmax ). Forty-five healthy volunteers were enrolled, 22 in
the AAA arm and 23 in the NXA arm. Under fasting conditions, the AUCinf ,
AUClast , and Cmax of the AAA tablet were similar to those of the capsule, but
slightly higher (∼20%) for NXA and decreased with a high-fat meal (∼65%) and a
low-fat meal (∼30%) for both tablet formulations. Overall, 20 participants (9 in
the AAA arm; 11 in the NXA arm) experienced at least 1 adverse event, the most
common in both arms being headache. The study showed that under fasting
conditions, tablet AAA had bioavailability similar to that in the capsule CSF.
The bioavailability of both tablet formulations decreased with food, with a more
pronounced effect observed with a high-fat meal. Asciminib is a potent, specific BCR-ABL1 inhibitor being developed for the
treatment of patients with chronic myelogenous leukemia (CML) and Philadelphia
chromosome positive acute lymphoblastic leukemia (Ph + ALL).Here, we present the
results of human oral absorption, distribution, metabolism, excretion (ADME) and
in vitro studies that together provide an overall understanding of the
metabolism, distribution and clearance of asciminib in humans.Asciminib was
rapidly absorbed with a maximum plasma concentration at two hours post-dose.
Total radioactivity and asciminib showed similar terminal half-lives in
plasma.Oral asciminib absorption ranged between a minimum of 33%, and a maximum
of 57% based on the metabolite profiles of late time-point feces
collections.Asciminib was eliminated mainly through feces via unchanged
asciminib excretion and metabolism.Direct glucuronidation and oxidation were
major metabolic pathways in human that were catalyzed predomitly by
UDP-glucuronosyltransferase (UGT)2B7 and cytochrome P450 (CYP)3A4,
respectively.The relative contribution of the glucuronidation pathway to the
total clearance of asciminib via metabolism is estimated to range ∼28-58%,
whereas the relative contribution of the oxidative pathway is estimated to range
∼37-64%, based upon the maximum oral absorption in humans. Author information:
(1)OHSU Knight Cancer Institute, Oregon Health & Science University, 3181 SW Sam
Jackson Park Road, LBRB 513, Portland, OR 97239, USA; Howard Hughes Medical
Institute, Portland, OR 97239, USA; Division of Hematology and Medical Oncology,
Oregon Health & Science University, Portland, OR 97239, USA.
(2)Huntsman Cancer Institute, University of Utah, 2000 Circle of Hope, Room
4280, Salt Lake City, UT 84112, USA.
(3)OHSU Knight Cancer Institute, Oregon Health & Science University, 3181 SW Sam
Jackson Park Road, LBRB 513, Portland, OR 97239, USA; Division of Hematology and
Medical Oncology, Oregon Health & Science University, Portland, OR 97239, USA.
(4)Huntsman Cancer Institute, University of Utah, 2000 Circle of Hope, Room
4280, Salt Lake City, UT 84112, USA; Department of Hematology, Nanfang Hospital,
Southern Medical University, Guangzhou, Guangdong, People's Republic of China.
(5)Department of Pathology, University of Utah, Salt Lake City, UT 84112, USA.
(6)ARUP Laboratories, Salt Lake City, UT 84108, USA.
(7)OHSU Knight Cancer Institute, Oregon Health & Science University, 3181 SW Sam
Jackson Park Road, LBRB 513, Portland, OR 97239, USA; Portland VA Health Care
System, Portland, OR, USA; Department of Cell, Developmental, & Cancer Biology,
Oregon Health & Science University, Portland, OR 97239, USA.
(8)OHSU Knight Cancer Institute, Oregon Health & Science University, 3181 SW Sam
Jackson Park Road, LBRB 513, Portland, OR 97239, USA; Department of Cell,
Developmental, & Cancer Biology, Oregon Health & Science University, Portland,
OR 97239, USA.
(9)Service d'Hematologie Adulte, INSERM UMR 1160, Hospital Saint-Louis, 75010
Paris, France.
(10)Laboratory of Hematology, University Hospital Saint-Louis, AP-HP and EA3518,
University Paris Diderot, Paris, France.
(11)Leukemia Research Institute, The Catholic University of Korea, Seoul,
Republic of Korea; Department of Hematology, Seoul St Mary's Hospital, The
Catholic University of Korea, Seoul, Republic of Korea.
(12)Huntsman Cancer Institute, University of Utah, 2000 Circle of Hope, Room
4280, Salt Lake City, UT 84112, USA; Division of Hematology and Hematologic
Maligcies, University of Utah, Salt Lake City, UT 84112, USA.
(13)OHSU Knight Cancer Institute, Oregon Health & Science University, 3181 SW
Sam Jackson Park Road, LBRB 513, Portland, OR 97239, USA; Howard Hughes Medical
Institute, Portland, OR 97239, USA; Division of Hematology and Medical Oncology,
Oregon Health & Science University, Portland, OR 97239, USA. Electronic address:
[email protected].
(14)Huntsman Cancer Institute, University of Utah, 2000 Circle of Hope, Room
4280, Salt Lake City, UT 84112, USA; Division of Hematology and Hematologic
Maligcies, University of Utah, Salt Lake City, UT 84112, USA. Electronic
address: [email protected]. |
Please list 2 human diseases caused by a coronavirus. | Middle East respiratory syndrome (MERS) and SARS are diseases caused by a coronavirus. | First identified in 2012, Middle East respiratory syndrome (MERS) is caused by
an emerging human coronavirus, which is distinct from the severe acute
respiratory syndrome coronavirus (SARS-CoV), and represents a novel member of
the lineage C betacoronoviruses. Since its identification, MERS coronavirus
(MERS-CoV) has been linked to more than 1372 infections manifesting with severe
morbidity and, often, mortality (about 495 deaths) in the Arabian Peninsula,
Europe, and, most recently, the United States. Human-to-human transmission has
been documented, with nosocomial transmission appearing to be an important route
of infection. The recent increase in cases of MERS in the Middle East coupled
with the lack of approved antiviral therapies or vaccines to treat or prevent
this infection are causes for concern. We report on the development of a
synthetic DNA vaccine against MERS-CoV. An optimized DNA vaccine encoding the
MERS spike protein induced potent cellular immunity and antigen-specific
neutralizing antibodies in mice, macaques, and camels. Vaccinated rhesus
macaques seroconverted rapidly and exhibited high levels of virus-neutralizing
activity. Upon MERS viral challenge, all of the monkeys in the
control-vaccinated group developed characteristic disease, including pneumonia.
Vaccinated macaques were protected and failed to demonstrate any clinical or
radiographic signs of pneumonia. These studies demonstrate that a consensus MERS
spike protein synthetic DNA vaccine can induce protective responses against
viral challenge, indicating that this strategy may have value as a possible
vaccine modality against this emerging pathogen. Author information:
(1)National Institute for Viral Disease Control and Prevention, Chinese Center
for Disease Control and Prevention (China CDC), Beijing, 100052, China; College
of Laboratory Medicine and Life Sciences, Wenzhou Medical University, Wenzhou,
325035, China; Shenzhen Key Laboratory of Pathogen and Immunity, Shenzhen Third
People's Hospital, Shenzhen, 518112, China. Electronic address:
[email protected].
(2)CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of
Microbiology, Chinese Academy of Sciences (CAS), Beijing, 100101, China;
University of Chinese Academy of Sciences, Beijing, 100049, China.
(3)National Institute for Viral Disease Control and Prevention, Chinese Center
for Disease Control and Prevention (China CDC), Beijing, 100052, China; College
of Laboratory Medicine and Life Sciences, Wenzhou Medical University, Wenzhou,
325035, China.
(4)CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of
Microbiology, Chinese Academy of Sciences (CAS), Beijing, 100101, China;
University of Chinese Academy of Sciences, Beijing, 100049, China; Research
Network of Immunity and Health (RNIH), Beijing Institutes of Life Science,
Chinese Academy of Sciences, Beijing, 100101, China.
(5)Shenzhen Key Laboratory of Pathogen and Immunity, Shenzhen Third People's
Hospital, Shenzhen, 518112, China; CAS Key Laboratory of Pathogenic Microbiology
and Immunology, Institute of Microbiology, Chinese Academy of Sciences (CAS),
Beijing, 100101, China.
(6)National Institute for Viral Disease Control and Prevention, Chinese Center
for Disease Control and Prevention (China CDC), Beijing, 100052, China; Shenzhen
Key Laboratory of Pathogen and Immunity, Shenzhen Third People's Hospital,
Shenzhen, 518112, China; CAS Key Laboratory of Pathogenic Microbiology and
Immunology, Institute of Microbiology, Chinese Academy of Sciences (CAS),
Beijing, 100101, China; University of Chinese Academy of Sciences, Beijing,
100049, China; Research Network of Immunity and Health (RNIH), Beijing
Institutes of Life Science, Chinese Academy of Sciences, Beijing, 100101, China.
Electronic address: [email protected]. Since severe acute respiratory syndrome (SARS) and Middle East respiratory
syndrome (MERS) coronaviruses (CoVs) share similar characteristics with respect
to clinical signs, etiology, and transmission, methods for a rapid and accurate
differential diagnosis are important. Therefore, the aim of this study was to
develop a duplex real-time reverse transcription (RT)-PCR method for the
simultaneous detection of these viruses. Primers and probes that target the
conserved spike S2 region of human SARS-CoV, MERS-CoV, and their related bat
CoVs were designed. The results of real-time RT-PCR showed specific reactions
for each virus with adequate detection limits of 50-100 copies/mL and
5-100 copies/mL using pUC57-SARS-pS2 (a template for SARS-CoV) and pGEM-MERS-S2
(a template for MERS-CoV), respectively. In addition, this real-time RT-PCR
system was able to detect the target viruses SARS-like bat CoV and MERS-CoV in
bat fecal samples and sputum of MERS patients, respectively. Therefore, this
newly developed real-time RT-PCR method is expected to detect not only SARS-CoV
and MERS-CoV in humans but also several bat CoVs that are closely related to
these viruses in bats. Human coronaviruses (hCoVs) can be divided into low pathogenic and highly
pathogenic coronaviruses. The low pathogenic CoVs infect the upper respiratory
tract and cause mild, cold-like respiratory illness. In contrast, highly
pathogenic hCoVs such as severe acute respiratory syndrome CoV (SARS-CoV) and
Middle East respiratory syndrome CoV (MERS-CoV) predomitly infect lower
airways and cause fatal pneumonia. Severe pneumonia caused by pathogenic hCoVs
is often associated with rapid virus replication, massive inflammatory cell
infiltration and elevated pro-inflammatory cytokine/chemokine responses
resulting in acute lung injury (ALI), and acute respiratory distress syndrome
(ARDS). Recent studies in experimentally infected animal strongly suggest a
crucial role for virus-induced immunopathological events in causing fatal
pneumonia after hCoV infections. Here we review the current understanding of how
a dysregulated immune response may cause lung immunopathology leading to
deleterious clinical manifestations after pathogenic hCoV infections. Emerging and re-emerging pathogens represent a substantial threat to public
health, as demonstrated with numerous outbreaks over the past years, including
the 2013-2016 outbreak of Ebola virus in western Africa. Coronaviruses are also
a threat for humans, as evidenced in 2002/2003 with infection by the severe
acute respiratory syndrome coronavirus (SARS-CoV), which caused more than 8000
human infections with 10% fatality rate in 37 countries. Ten years later, a
novel human coronavirus (Middle East respiratory syndrome coronavirus,
MERS-CoV), associated with severe pneumonia, arose in the Kingdom of Saudi
Arabia. Until December 2016, MERS has accounted for more than 1800 cases and 35%
fatality rate. Finding an animal model of disease is key to develop vaccines or
antivirals against such emerging pathogens and to understand its pathogenesis.
Knowledge of the potential role of domestic livestock and other animal species
in the transmission of pathogens is of importance to understand the epidemiology
of the disease. Little is known about MERS-CoV animal host range. In this paper,
experimental data on potential hosts for MERS-CoV is reviewed. Advantages and
limitations of different animal models are evaluated in relation to viral
pathogenesis and transmission studies. Finally, the relevance of potential new
target species is discussed. Coronaviruses are pathogens with a serious impact on human and animal health.
They mostly cause enteric or respiratory disease, which can be severe and life
threatening, e.g., in the case of the zoonotic coronaviruses causing severe
acute respiratory syndrome (SARS) and Middle East Respiratory Syndrome (MERS) in
humans. Despite the economic and societal impact of such coronavirus infections,
and the likelihood of future outbreaks of additional pathogenic coronaviruses,
our options to prevent or treat coronavirus infections remain very limited. This
highlights the importance of advancing our knowledge on the replication of these
viruses and their interactions with the host. Compared to other +RNA viruses,
coronaviruses have an exceptionally large genome and employ a complex genome
expression strategy. Next to a role in basic virus replication or virus
assembly, many of the coronavirus proteins expressed in the infected cell
contribute to the coronavirus-host interplay. For example, by interacting with
the host cell to create an optimal environment for coronavirus replication, by
altering host gene expression or by counteracting the host's antiviral defenses.
These coronavirus-host interactions are key to viral pathogenesis and will
ultimately determine the outcome of infection. Due to the complexity of the
coronavirus proteome and replication cycle, our knowledge of host factors
involved in coronavirus replication is still in an early stage compared to what
is known for some other +RNA viruses. This review summarizes our current
understanding of coronavirus-host interactions at the level of the infected
cell, with special attention for the assembly and function of the viral
RNA-synthesising machinery and the evasion of cellular innate immune responses. Middle East respiratory syndrome coronavirus (MERS-CoV) is a novel human
coronavirus that can cause human respiratory disease. The development of a
detection method for this virus that can lead to rapid and accurate diagnosis
would be significant. In this study, we established a nucleic acid visualization
technique that combines the reverse transcription loop-mediated isothermal
amplification technique and a vertical flow visualization strip (RT-LAMP-VF) to
detect the N gene of MERS-CoV. The RT-LAMP-VF assay was performed in a constant
temperature water bath for 30 min, and the result was visible by the naked eye
within 5 min. The RT-LAMP-VF assay was capable of detecting 2 × 101 copies/μl of
synthesized RNA transcript and 1 × 101 copies/μl of MERS-CoV RNA. The method
exhibits no cross-reactivities with multiple CoVs including SARS-related
(SARSr)-CoV, HKU4, HKU1, OC43 and 229E, and thus exhibits high specificity.
Compared to the real-time RT-PCR (rRT-PCR) method recommended by the World
Health Organization (WHO), the RT-LAMP-VF assay is easy to handle, does not
require expensive equipment and can rapidly complete detection within 35 min. Human coronavirus (HCoV) infection causes respiratory diseases with mild to
severe outcomes. In the last 15 years, we have witnessed the emergence of two
zoonotic, highly pathogenic HCoVs: severe acute respiratory syndrome coronavirus
(SARS-CoV) and Middle East respiratory syndrome coronavirus (MERS-CoV).
Replication of HCoV is regulated by a diversity of host factors and induces
drastic alterations in cellular structure and physiology. Activation of critical
signaling pathways during HCoV infection modulates the induction of antiviral
immune response and contributes to the pathogenesis of HCoV. Recent studies have
begun to reveal some fundamental aspects of the intricate HCoV-host interaction
in mechanistic detail. In this review, we summarize the current knowledge of
host factors co-opted and signaling pathways activated during HCoV infection,
with an emphasis on HCoV-infection-induced stress response, autophagy,
apoptosis, and innate immunity. The cross talk among these pathways, as well as
the modulatory strategies utilized by HCoV, is also discussed. |
What is characteristic to Fitz-Hugh–Curtis syndrome? | Fitz-Hugh-Curtis syndrome is a rare complication of pelvic inflammatory disease that involves liver capsule inflammation associated with genital tract infection, which is usually caused by Neisseria gonorrhoea and Chlamydia trachomatis. | The Fitz-Hugh--Curtis syndrome is an extragenital manifestation of gonorrhea,
characterized by fibrinous inflammation of the subphrenic area with
violinstring-like adhesions between the liver surface and the parietal
peritoneum. When such patients present with acute upper right quadrant pain, the
differential diagnosis to other abdominal emergencies (cholecystitis, peptic
ulcer disease etc.) may be difficult, because it will not always be possible to
isolate the causative agent from the external genitals. In such cases only a
laparoscopic approach will allow a correct diagnosis. Two case reports are
discussed in the light of the literature. Perihepatitis or Fitz-Hugh-Curtis syndrome is a complication of pelvic
inflammatory disease that usually leaves characteristic violin string adhesions
on the anterior liver surface. These adhesions are common incidental findings on
subsequent laparoscopy or laparotomy and are considered benign. We present a
case of partial mechanical small bowel obstruction as a sequel of this syndrome
that was diagnosed and treated laparoscopically. AIM: To analyze the clinical characteristics of patients diagnosed with
Fitz-Hugh-Curtis syndrome.
METHODS: The clinical courses of patients that visited St. Mary's Hospital with
abdominal pain from January 2005 to December 2006 and were diagnosed with
Fitz-Hugh-Curtis syndrome were examined.
RESULTS: Fitz-Hugh-Curtis syndrome was identified in 22 female patients of
childbearing age; their mean age was 31.0+/-8.1 years. Fourteen of these cases
presented with pain in the upper right abdomen alone or together with pain in
the lower abdomen, and six patients presented with pain only in the lower
abdomen. The first impression at the time of visit was acute cholecystitis or
cholangitis in 10 patients and acute appendicitis or pelvic inflammatory disease
in eight patients. Twenty-one patients were diagnosed by abdominal computer
tomography (CT), and the results of abdominal sonography were normal for 10 of
these patients. Chlamydia trichomatis was isolated from 18 patients. Two
patients underwent laparoscopic adhesiotomy and 20 patients were completely
cured by antibiotic treatment.
CONCLUSION: For women of childbearing age with acute pain in the upper right
abdomen alone or together with pain in the lower abdomen, Fitz-Hugh-Curtis
syndrome should be considered during differential diagnosis. Moreover, in cases
suspected to be Fitz-Hugh-Curtis syndrome, abdominal CT, rather than abdominal
sonography, assists in the diagnosis. BACKGROUND: There are a lot of different causes of abdominal pain; in this case,
a young woman suffers from three diseases with similar symptoms. Adult
intestinal mal-rotation is a rare condition of deviation from the normal 270°
counter clockwise rotation of the midgut resulting in, not only mal-position of
the small intestine, but also mal-fixation of the mesentery. Fitz-Hugh-Curtis
syndrome is a rare complication of pelvic inflammatory disease; it involves
liver capsule inflammation associated with genital tract infection, which is
usually caused by Neisseria gonorrhoea and Chlamydia trachomatis. Neuroendocrine
tumors are enterochromaffin cell neoplasms that arise from cells of the
endocrine (hormonal) and nervous systems; the appendicular one is the most
common primary maligt lesion of these tumors, it's incidence is about 0.3 -
0.9% of appendectomies done. Just for knowledge, this is the first described
case of concomitant presence of all these diseases with clinical symptoms
attributable to each one.
CASE PRESENTATION: 40-years-old woman suffers from acute abdominal pain,
predomitly on the right quadrants, without abdominal distension, no guarding
nor rigidity and normal intestinal peristalsis. She has a long history of
abdominal intermittent pain, with cramps every 30-40 min, resolving
spontaneously. She was diagnosed as intestinal mal-rotation through computed
tomography scan which has evidenced a mobilized intra--peritoneal duodenum with
cecum/ascending colon predominately lying on the left side and the small
intestine almost entirely lying on the right side of abdomen, without evidence
of effusion, edema or signs of intestinal ischemia or infarction. Exploratory
laparoscopy demonstrated an inflammatory process in the hepatic-renal space,
with bloody adhesions above the liver capsule; this is additional to the typical
pelvic inflammatory disease signs (Fitz-Hugh-Curtis syndrome). Appendectomy was
performed with histological analysis resulting in appendicular neuroendocrine
tumor.
CONCLUSIONS: Although the patient has an intestinal mal-rotation which could
explain the abdominal painful symptoms, it is not possible to exclude other
concomitant causes, such as perihepatitis on pelvic inflammatory disease or
neuroendocrine tumors. Even if all these diseases are rarely seen in daily
clinical practice, they should be considered in the differential diagnosis of
chronic intermittent abdominal pain in a young woman. BACKGROUND: Fitz-Hugh-Curtis syndrome is defined as perihepatitis associated
with pelvic inflammatory disease. Chlamydia trachomatis is one of its most
common aetiologies. This syndrome usually presents with right upper quadrant
abdominal pain mimicking other hepatobiliary and gastrointestinal pathologies,
hence, posing a diagnostic dilemma in settings with limited diagnostic tools.
CASE REPORT: A 32 year old African female presented with acute right upper
quadrant abdominal pain and vaginal discharge, for which she had previously
received treatment in another health center with no improvement. Clinical and
laboratory findings were suggestive of Fitz-Hugh-Curtis syndrome. Five days
after treatment with oral doxycycline, the patient showed marked clinical
improvement.
CONCLUSION: Fitz-Hugh-Curtis syndrome is a common cause of right upper quadrant
pain which is often under diagnosed in poor communities. Hence, it should be
included as a differential diagnosis in patients presenting with right upper
quadrant pain, especially in females of reproductive age. BACKGROUND Fitz-Hugh-Curtis (FHC) syndrome is a perihepatitis linked to
inflammatory pelvic disease. It can be caused by Neisseria gonorrhoeae or
Chlamydia trachomatis infections. FHC syndrome usually presents with pain in the
right hypochondrium and fever, associated with symptoms and signs of pelvic
infection in women. CASE REPORT We present the case of a 22-year-old woman with
systemic lupus erythematous (SLE) who presented with polyarthritis, cutaneous
lesions, and abdominal pain. The diagnosis of FHC syndrome was based on the
findings of abdominal computerized tomography (CT) and the isolation of
Neisseria gonorrhoeae (NG) in blood cultures. The association of arthritis and
cutaneous lesions was diagnosed as a syndrome of arthritis-dermatitis, also
caused by systemic NG infection. The patient had a favorable outcome with
antibiotic treatment. CONCLUSIONS FHC syndrome should be considered in sexually
active young patients, mainly women, with pelvic infection and perihepatitis. It
may be caused by disseminated gonococcal infection. An important risk factor is
the serum complement deficit, which may predispose to severe forms. Low serum
complement level is a frequent manifestation of active SLE. CT images showing
the typical findings of perihepatitis allow making the correct diagnosis. Fitz-Hugh-Curtis syndrome (FHCS) is characterized by perihepatic and pelvic
inflammation and occurs mostly in women of childbearing age. Here, we report a
case of FHCS caused by Chlamydia trachomatis in a 50-year-old man. The patient
presented to our hospital with right upper quadrant abdominal pain, and enhanced
computed tomography revealed perihepatic and pelvic free fluid and early-phase
hepatic capsular enhancement. A urine specimen was positive for Chlamydia
trachomatis. The patient was diagnosed with FHCS due to Chlamydia trachomatis
infection. In conclusion, FHCS cannot be excluded when men present with right
upper quadrant abdominal pain without significant signs of biliary tract
disease. BACKGROUND: Fitz-Hugh-Curtis syndrome or acute perihepatitis is considered a
rare complication of pelvic inflammatory disease, mostly associated with
chlamydial or gonococcal salpingitis. Peritoneal tuberculosis is a rare site of
extra-pulmonary infection caused by Mycobacterium tuberculosis. Infection
usually occurs after reactivation of latent tuberculous foci in the peritoneum
and more seldom after contiguous spread from tuberculous salpingitis.
CASE PRESENTATION: We describe a case of a 21-year old female of Somalian origin
diagnosed with Fitz-Hugh Curtis syndrome associated with tuberculous salpingitis
and peritonitis, presenting with new onset ascites. Acid fast stained smear and
polymerase chain reaction for Mycobacterium tuberculosis on ascitic fluid,
endocervical culture and tuberculin skin test were all negative. Eventually, the
diagnosis was made laparoscopically, showing multiple peritoneal white nodules
and perihepatic "violin string" fibrinous strands.
CONCLUSIONS: To our knowledge, this is the first case where Fitz-Hugh-Curtis
syndrome is associated with both peritoneal and genital tuberculosis and where
ascites was the primary clinical finding. Female genital tuberculosis has only
rarely been associated with Fitz-Hugh-Curtis syndrome and all cases presented
with chronic abdominal pain and/or infertility. Ascites and peritoneal
involvement was not present in any case. Moreover, most patients with
Fitz-Hugh-Curtis syndrome show no evidence of generalized intra-abdominal
infection and only occasionally have concomitant ascites. El síndrome de Fitz-Hugh-Curtis (FHCS) es la inflamación de la cápsula hepática
sin afectación del parénquima asociada a una enfermedad pélvica inflamatoria.
Hay muy pocos casos descritos en varones. El síntoma característico es el dolor
abdominal en el cuadrante superior derecho, que hace que se confunda el cuadro
con una enfermedad de la vía biliar. Son características las adherencias fuertes
entre el diafragma y el hígado en forma de «cuerda de violín». Presentamos el
caso de un varón de 81 años que se somete a una colecistectomía laparoscópica
por pancreatitis de repetición. Durante la cirugía se encuentran las
características adherencias en «cuerda de violín», que se seccio. El paciente
da positivo para anticuerpos contra Chlamydia trachomatis. Hay nueve casos
descritos en la literatura de FHCS en varones. Este síndrome se confunde muchas
veces con patología infecciosa biliar, lo que nos obliga a someter al paciente a
una cirugía para realizar el diagnóstico cuando se encuentran las
características adherencias. Si sospechamos la enfermedad mediante las pruebas
complementarias, podemos intentar tratarla con antibióticos. Fitz-Hugh-Curtis
syndrome (FHCS) is the inflammation of the hepatic capsule without affecting the
parenchyma, which is associated with a pelvic inflammatory disease. There have
been very few cases in men. The main symptom is abdominal pain in the right
upper quadrant, which can be confused with a bile duct disorder. Strong violin
string-like adhesions between the diaphragm and the liver are characteristic. In
the study concerned, it is reported the case of an 81 year-old man who undergoes
a laparoscopic cholecystectomy for recurrent pancreatitis. During surgery, the
typical violin string-like adhesions are found and sectioned. The patient tests
positive for Chlamydia trachomatis antibodies. Only nine cases in men have been
reported in FHCS literature. This syndrome is frequently confused with
infectious biliary tract disease, so the patient should undergo a surgery to
diagnose when the characteristic adhesions are found. If the disease is
suspected by the additional tests, it can be treated with antibiotics. |
What is the trade name of sildenafil? | The trade name of sildenafil is Viagra. | BACKGROUND: Chronic drug abuse and sexual dysfunction specifically erectile
dysfunction may lead drug abusers to seek over-the-counter or non-prescription
medications, out of which Sildenafil citrate, sold as the trade name of Viagra®
can be considered as a prime and important treatment. Therefore, the research
purpose was to draw a comparison and review the role of methamphetamine abuse
and sildenafil use in increasing the likelihood of high-risk sexual behaviors
(both concomitant and non-concomitant use).
METHODS: Hence, a total of 40 patients diagnosed with methamphetamine abuse were
recruited through the administration of structured clinical interview for DSM-IV
(Diagnostic and Statistical Manual of Mental Disorders, 4th Edition), through
purposive sampling and subsequent to being qualified in accordance with the
selection criteria by psychologists and general practitioners. All the 40 drug
abusers (20 methamphetamine abusers with concomitant use of Aphrodisiac drugs
(sexual stimulant pills) and 20 methamphetamine abusers) described their sexual
risk behaviors subsequent to the drug use.
FINDINGS: Supported the between-group difference that is to say that, the group
with concomitant methamphetamine abuse differed significantly in all the items
when compared with the control group. However, this group scored lower on the
item of sexual intercourse with drug addicted prostitutes using condom and both
groups demonstrated high pick on this item.
CONCLUSION: Overall, the concomitant methamphetamine chronic abuse with sexual
stimulant drugs generates Aphrodisiac drugs impulses and is found to be related
to higher frequencies of sexual risk behaviors and sexual intercourse with
addicted prostitutes. |
How large is the SARS-CoV proteome? | The severe acute respiratory syndrome coronavirus (SARS-CoV) genome is predicted to encode 14 functional open reading frames, leading to the expression of up to 30 structural and non-structural protein products. | The proteomes of the severe acute respiratory syndrome-associated coronavirus
(SARS-CoV) and its infected Vero E6 cells were detected in the present study.
The cytosol and nucleus fractions of virus-infected cells as well as the crude
virions were analyzed either by one-dimensional electrophoresis followed by
ESI-MS/MS identification or by shotgun strategy with two-dimensional liquid
chromatography-ESI-MS/MS. For the first time, all of the four predicted
structural proteins of SARS-CoV were identified, including S (Spike), M
(Membrane), N (Nucleocapsid), and E (Envolope) proteins. In addition, a novel
phosphorylated site of M protein was observed. The combination of these gel-base
and non-gel methods provides fast and complimentary approaches to SARS-CoV
proteome and can be widely used in the analysis of other viruses. The severe acute respiratory syndrome coronavirus (SARS-CoV) genome is predicted
to encode 14 functional open reading frames, leading to the expression of up to
30 structural and non-structural protein products. The functions of a large
number of viral ORFs are poorly understood or unknown. In order to gain more
insight into functions and modes of action and interaction of the different
proteins, we cloned the viral ORFeome and performed a genome-wide analysis for
intraviral protein interactions and for intracellular localization. 900 pairwise
interactions were tested by yeast-two-hybrid matrix analysis, and more than 65
positive non-redundant interactions, including six self interactions, were
identified. About 38% of interactions were subsequently confirmed by CoIP in
mammalian cells. Nsp2, nsp8 and ORF9b showed a wide range of interactions with
other viral proteins. Nsp8 interacts with replicase proteins nsp2, nsp5, nsp6,
nsp7, nsp8, nsp9, nsp12, nsp13 and nsp14, indicating a crucial role as a major
player within the replication complex machinery. It was shown by others that
nsp8 is essential for viral replication in vitro, whereas nsp2 is not. We show
that also accessory protein ORF9b does not play a pivotal role for viral
replication, as it can be deleted from the virus displaying normal plaque sizes
and growth characteristics in Vero cells. However, it can be expected to be
important for the virus-host interplay and for pathogenicity, due to its large
number of interactions, by enhancing the global stability of the SARS proteome
network, or play some unrealized role in regulating protein-protein
interactions. The interactions identified provide valuable material for future
studies. |
Is Apremilast effective for Behçet’s Syndrome? | Yes, Apremilast is effective for Behcet's Syndrome | BACKGROUND: Oral ulcers, the hallmark of Behçet's syndrome, can be resistant to
conventional treatment; therefore, alternative agents are needed. Apremilast is
an oral phosphodiesterase-4 inhibitor that modulates several inflammatory
pathways.
METHODS: We conducted a phase 2, multicenter, placebo-controlled study in which
111 patients with Behçet's syndrome who had two or more oral ulcers were
randomly assigned to receive 30 mg of apremilast twice daily or placebo for 12
weeks. This regimen was followed by a 12-week extension phase in which the
placebo group was switched to apremilast and a 28-day post-treatment
observational follow-up phase. The patients and clinicians were unaware of the
study assignments throughout the trial. The primary end point was the number of
oral ulcers at week 12. Secondary outcomes included pain from these ulcers
(measured on a 100-mm visual-analogue scale, with higher scores indicating worse
pain), the number of genital ulcers, overall disease activity, and quality of
life.
RESULTS: The mean (±SD) number of oral ulcers per patient at week 12 was
significantly lower in the apremilast group than in the placebo group (0.5±1.0
vs. 2.1±2.6) (P<0.001). The mean decline in pain from oral ulcers from baseline
to week 12 was greater with apremilast than with placebo (-44.7±24.3 mm vs.
-16.0±32.5 mm) (P<0.001). Nausea, vomiting, and diarrhea were more common in the
apremilast group (with 22, 9, and 12 incidents, respectively, among 55 patients)
than in the placebo group (with 10, 1, and 2 incidents, respectively, among 56
patients), findings that were similar to those in previous studies of
apremilast. There were two serious adverse events in patients receiving
apremilast.
CONCLUSIONS: Apremilast was effective in treating oral ulcers, which are the
cardinal manifestation of Behçet's syndrome. This preliminary study was neither
large enough nor long enough to assess long-term efficacy, the effect on other
manifestations of Behçet's syndrome, or the risk of uncommon serious adverse
events. (Funded by Celgene; ClinicalTrials.gov number, NCT00866359.). INTRODUCTION: Behçet's syndrome (BS) is a systemic inflammatory disorder
characterized by a wide range of potential clinical manifestations with no
gold-standard therapy. However, the recent classification of BS at a crossroads
between autoimmune and autoinflammatory syndromes has paved the way to new
further therapeutic opportunities in addition to anti-tumor necrosis factor
agents.
AREAS COVERED: This review provides a digest of all current experience and
evidence about pharmacological agents recently described as having a role in the
treatment of BS, including interleukin (IL)-1 inhibitors, tocilizumab,
rituximab, alemtuzumab, ustekinumab, interferon-alpha-2a, and apremilast.
EXPERT OPINION: IL-1 inhibitors currently represent the most studied agents
among the latest treatment options for BS, proving to be effective, safe and
with an acceptable retention on treatment. However, since BS is a peculiar
disorder with clinical features responding to certain treatments that in turn
can worsen other manifestations, identifying new treatment options for patients
unresponsive to the current drug armamentarium is of great relevance. A number
of agents have been studied in the last decade showing changing fortunes in some
cases and promising results in others. The latter will potentially provide their
contribution for better clinical management of BS, improving patients' quality
of life and long-term outcome. PURPOSE OF REVIEW: New treatment options have been studied over the last several
years, with a recent approval, a first for Behçet syndrome, in the United
States. New management guidelines have also been published, helping with this
nowadays more commonly recognized condition's management. The goal of this
review is to summarize the most important and potentially clinically relevant
recent developments and discuss their impact in the management of patients with
Behçet syndrome.
RECENT FINDINGS: Apremilast is now approved for the treatment of oral ulcer of
Behçet syndrome in the United States. It's possible benefits in controlling
nonoral ulcer features of the syndrome are awaited. Long-term use of tumor
necrosis factor inhibitors for the treatment of especially eye disease in Behçet
syndrome seems to be safe and efficacious. New treatment options such as
ustekinumab, secukinumab, tocilizumab and others have early promising data but
more studies are needed to better clarify their role in Behçet management.
SUMMARY: The last 2 years have not only seen the approval of the first drug
specifically labeled for the treatment of Behçet syndrome in the case of
apremilast, many groups have also presented and published their findings on
promising new therapeutic agents, which may soon be added to our tools in
treating this condition. We also know more about other drugs, such as tumor
necrosis factor inhibitors as many patients have been on these for long periods
of time, and long-term follow-up data seem to confirm their role in Behçet
treatment. Lack of placebo controlled, randomized trials, for the most part, are
still outstanding issues. BACKGROUND: The small-molecule phosphodiesterase 4 inhibitor apremilast
modulates cytokines that are up-regulated in Behçet's syndrome. In a phase 2
trial involving patients with Behçet's syndrome, apremilast reduced the
incidence and severity of oral ulcers. Data on the efficacy and safety of
apremilast in patients with Behçet's syndrome who had active oral ulcers and had
not previously received biologic agents are limited.
METHODS: In a phase 3 trial, we randomly assigned, in a 1:1 ratio, patients who
had Behçet's syndrome with active oral ulcers but no major organ involvement to
receive either apremilast at a dose of 30 mg or placebo, administered orally,
twice daily for 12 weeks, followed by a 52-week extension phase. The primary end
point was the area under the curve (AUC) for the total number of oral ulcers
during the 12-week placebo-controlled period (with lower values indicating fewer
ulcers). There were 13 secondary end points, including complete response of oral
ulcers, change from baseline in pain associated with oral ulcers, disease
activity, and change from baseline in the Behçet's Disease Quality of Life score
(range, 0 to 30, with higher scores indicating greater impairment in quality of
life). Safety was also assessed.
RESULTS: A total of 207 patients underwent randomization (104 patients to the
apremilast group and 103 to the placebo group). The AUC for the number of oral
ulcers was 129.5 for apremilast, as compared with 222.1 for placebo
(least-squares mean difference, -92.6; 95% confidence interval [CI], -130.6 to
-54.6; P<0.001). The change from baseline in the Behçet's Disease Quality of
Life score was -4.3 points in the apremilast group, as compared with -1.2 points
in the placebo group (least-squares mean difference, -3.1 points; 95% CI, -4.9
to -1.3). Adverse events with apremilast included diarrhea, nausea, and
headache.
CONCLUSIONS: In patients with oral ulcers associated with Behçet's syndrome,
apremilast resulted in a greater reduction in the number of oral ulcers than
placebo but was associated with adverse events, including diarrhea, nausea, and
headache. (Funded by Celgene; ClinicalTrials.gov number, NCT02307513.). |
Is Rad4/XPC a DNA damage sensing protein? | Yes,
DNA damage recognition is achieved by the Rad4/XPC nucleotide excision repair complex. | Mutations in the nucleotide excision repair (NER) pathway can cause the
xeroderma pigmentosum skin cancer predisposition syndrome. NER lesions are
limited to one DNA strand, but otherwise they are chemically and structurally
diverse, being caused by a wide variety of genotoxic chemicals and ultraviolet
radiation. The xeroderma pigmentosum C (XPC) protein has a central role in
initiating global-genome NER by recognizing the lesion and recruiting downstream
factors. Here we present the crystal structure of the yeast XPC orthologue Rad4
bound to DNA containing a cyclobutane pyrimidine dimer (CPD) lesion. The
structure shows that Rad4 inserts a beta-hairpin through the DNA duplex, causing
the two damaged base pairs to flip out of the double helix. The expelled
nucleotides of the undamaged strand are recognized by Rad4, whereas the two
CPD-linked nucleotides become disordered. These findings indicate that the
lesions recognized by Rad4/XPC thermodynamically destabilize the Watson-Crick
double helix in a manner that facilitates the flipping-out of two base pairs. The xeroderma pigmentosum C (XPC) complex initiates nucleotide excision repair
by recognizing DNA lesions before recruiting downstream factors. How XPC detects
structurally diverse lesions embedded within normal DNA is unknown. Here we
present a crystal structure that captures the yeast XPC orthologue (Rad4) on a
single register of undamaged DNA. The structure shows that a disulphide-tethered
Rad4 flips out normal nucleotides and adopts a conformation similar to that seen
with damaged DNA. Contrary to many DNA repair enzymes that can directly reject
non-target sites as structural misfits, our results suggest that Rad4/XPC uses a
kinetic gating mechanism whereby lesion selectivity arises from the kinetic
competition between DNA opening and the residence time of Rad4/XPC per site.
This mechanism is further supported by measurements of Rad4-induced
lesion-opening times using temperature-jump perturbation spectroscopy. Kinetic
gating may be a general mechanism used by site-specific DNA-binding proteins to
minimize time-consuming interrogations of non-target sites. XPC has long been considered instrumental in DNA damage recognition during
global genome nucleotide excision repair (GG-NER). While this recognition is
crucial for organismal health and survival, as XPC's recognition of lesions
stimulates global genomic repair, more recent lines of research have uncovered
many new non-canonical pathways in which XPC plays a role, such as base excision
repair (BER), chromatin remodeling, cell signaling, proteolytic degradation, and
cellular viability. Since the first discovery of its yeast homolog, Rad4, the
involvement of XPC in cellular regulation has expanded considerably. Indeed, our
understanding appears to barely scratch the surface of the incredible potential
influence of XPC on maintaining proper cellular function. Here, we first review
the canonical role of XPC in lesion recognition and then explore the new world
of XPC function. DNA damage repair starts with the recognition of damaged sites from
predomitly normal DNA. In eukaryotes, diverse DNA lesions from environmental
sources are recognized by the xeroderma pigmentosum C (XPC) nucleotide excision
repair complex. Studies of Rad4 (radiation-sensitive 4; yeast XPC ortholog)
showed that Rad4 "opens" up damaged DNA by inserting a β-hairpin into the duplex
and flipping out two damage-containing nucleotide pairs. However, this DNA
lesion "opening" is slow (˜5-10 ms) compared with typical submillisecond
residence times per base pair site reported for various DNA-binding proteins
during 1D diffusion on DNA. To address the mystery as to how Rad4 pauses to
recognize lesions during diffusional search, we examine conformational dynamics
along the lesion recognition trajectory using temperature-jump spectroscopy.
Besides identifying the ˜10-ms step as the rate-limiting bottleneck towards
opening specific DNA site, we uncover an earlier ˜100- to 500-μs step that we
assign to nonspecific deformation (unwinding/"twisting") of DNA by Rad4. The
β-hairpin is not required to unwind or to overcome the bottleneck but is
essential for full nucleotide-flipping. We propose that Rad4 recognizes lesions
in a step-wise "twist-open" mechanism, in which preliminary twisting represents
Rad4 interconverting between search and interrogation modes. Through such
conformational switches compatible with rapid diffusion on DNA, Rad4 may stall
preferentially at a lesion site, offering time to open DNA. This study
represents the first direct observation, to our knowledge, of dynamical DNA
distortions during search/interrogation beyond base pair breathing.
Submillisecond interrogation with preferential stalling at cognate sites may be
common to various DNA-binding proteins. Author information:
(1)Department of Pharmacology and Chemical Biology, University of Pittsburgh
School of Medicine, Pittsburgh, PA 15213, USA; University of Pittsburgh Cancer
Institute, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213,
USA.
(2)Department of Chemistry, University of Illinois at Chicago, Chicago, IL
60607, USA.
(3)Department of Physics and Astronomy, University of South Carolina, Columbia,
SC 29208, USA.
(4)School of Molecular Biosciences, Washington State University, Pullman, WA
99164, USA.
(5)Department of Microbiology and Molecular Genetics, University of Pittsburgh
School of Medicine, Pittsburgh, PA 15213, USA; University of Pittsburgh Cancer
Institute, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213,
USA.
(6)School of Biosciences, University of Kent, Canterbury, Kent CT2 7NJ, UK.
(7)Center for Biologic Imaging, University of Pittsburgh School of Medicine,
Pittsburgh, PA 15261, USA.
(8)Department of Chemistry, University of Illinois at Chicago, Chicago, IL
60607, USA. Electronic address: [email protected].
(9)Department of Pharmacology and Chemical Biology, University of Pittsburgh
School of Medicine, Pittsburgh, PA 15213, USA; University of Pittsburgh Cancer
Institute, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213,
USA. Electronic address: [email protected]. In plants, exposure to solar ultraviolet (UV) light is unavoidable, resulting in
DNA damage. Damaged DNA causes mutations, replication arrest, and cell death,
thus efficient repair of the damaged DNA is essential. A light-independent DNA
repair pathway called nucleotide excision repair (NER) is conserved throughout
evolution. For example, the damaged DNA-binding protein Radiation sensitive 4
(Rad4) in Saccharomyces cerevisiae is homologous to the mammalian NER protein
Xeroderma Pigmentosum complementation group C (XPC). In this study, we examined
the role of the Arabidopsis thaliana Rad4/XPC homologue (AtRAD4) in plant UV
tolerance by generating overexpression lines. AtRAD4 overexpression, both with
and without an N-terminal yellow fluorescent protein (YFP) tag, resulted in
increased UV tolerance. YFP-RAD4 localized to the nucleus, and UV treatment did
not alter this localization. We also used yeast two-hybrid analysis to examine
the interaction of AtRAD4 with Arabidopsis RAD23 and found that RAD4 interacted
with RAD23B as well as with the structurally similar protein HEMERA (HMR). In
addition, we found that hmr and rad23 mutants exhibited increased UV
sensitivity. Thus, our analysis suggests a role for RAD4 and RAD23/HMR in plant
UV tolerance. |
List symptoms of the Hakim Triad? | Triad of Hakim is well known for normal pressure hydrocephalus (NPH) and includes dementia, gait disturbances and urinary incontinence. | Three patients with normal pressure hydrocephalus and Parkinson's disease are
reported. The recognition of this association is important because these two
entities require specific therapeutic approaches. The presence of Parkinson's
disease does not preclude an excellent response of the hydrocephalus to a
shunting procedure. Although several reports of cases with the characteristic
clinical manifestations of normal pressure hydrocephalus--progressive dementia,
gait difficulty and urinary incontinence--have been published earlier, it was
Adams and Hakim who emphasized the clinical triad and the effect of shunting the
cerebrospinal fluid as a means of treatment. Messert and Baker stressed that the
gait disturbance had a close resemblance to the freezing gait of parkinsonism.
We are reporting three patients who had both conditions. Recognition of the
existence of both disorders in the same patients is important since appropriate
treatment of each of them led to marked improvement of their symptoms. Triad of Hakim--Adams is well known for normal pressure hydrocephalus (NPH):
dementia, gait disturbances and urinary incontinence. Variability of intensity
of these symptoms is obvious. However in clinical practice all classic signs are
present. We describe a case of posttraumatic NPH producing only gait impairment
with intact intellect and memory and bladder function. Such reports were not
found in literature. The definition of normal pressure hydrocephalus (NPH), in adults, associates
clinical signs (Adams and Hakim triad) involving gait disorders, urinary
incontinence and dementia, associated with aspects on brain imaging that are
consistent with this hypothesis and also normal or slightly increased
intracranial pressure. The aim of this study was to clarify the techniques and
methods facilitating the diagnosis of NPH. The literature review has been
conducted from the Medline database without date limitation including the
keywords "normal pressure hydrocephalus" and "diagnosis." They should appear in
the article title. From the 43 initially sorted, only 13 have been selected
using exclusion criteria. The proposed methods are very sparse and focused on
the improvement after surgical shunt. This focus is independent from the
diagnosis criteria proposed in 2005. This introduces an ambiguity in the
interpretation of the results. In practice, the diagnosis of NPH is more
difficult in the elderly population where differential diagnoses are frequent,
particularly vascular lesions (notably microangiopathy) and Alzheimer's disease.
The more invasive techniques as continuous spinal drainage (usually during 3
days) or some features of CSF dynamics (Rout, compliance) seem to be the best
predictors of after shunt improvement. However, these techniques are difficult
to use in routine in the elderly. The combination of Evans index and corpus
callosum angle on MRI is very useful to improve the differential diagnosis with
cerebral atrophy. Spinal tap test (lumbar puncture with the removal of 40 mL of
CSF) can be repeated two or three times for consecutive days to improve the
predictive value before shunting. Gait and balance often improve after shunt,
more than cognition and bladder disorders. In the elderly population, the
prognosis after 3 years is non conclusive despite initial improvement. Poor
prognosis seems to be due to associated pathologies in particular
neurodegenerative diseases. This should be considered in decision-making of CSF
shunt. BACKGROUND: Idiopathic normal pressure hydrocephalus (iNPH) is a type of
communicating hydrocephalus also known as non-obstructive hydrocephalus. This
type of hydrocephalus is caused by impaired cerebrospinal fluid reabsorption
without any obstruction in the ventricular system and is associated with normal
cerebrospinal fluid pressure. It is characterised clinically by gait
disturbance, cognitive dysfunction, and urinary incontinence (known as the
Hakim-Adams triad). The exact cause of iNPH is unknown. It may be managed
conservatively or treated surgically by inserting a ventriculoperitoneal (VP) or
ventriculoatrial (VA) shunt. However, a substantial number of patients do not
respond well to surgical treatment, complication rates are high and there is
often a need for further surgery. Endoscopic third ventriculostomy (ETV) is an
alternative surgical intervention. It has been suggested that ETV may lead to
better outcomes, including fewer complications.
OBJECTIVES: To determine the effectiveness of ETV for treatment of patients with
iNPH compared to conservative therapy, or shunting of CSF using VP or VA
shunts.To assess the perioperative and postoperative complication rates in
patients with iNPH after ETV compared to conservative therapy, VP or VA
shunting.
SEARCH METHODS: We searched for eligible studies using ALOIS: a comprehensive
register of dementia studies, The Cochrane Central Register of Controlled Trials
(CENTRAL) and several bibliographic databases such as MEDLINE (Ovid SP), EMBASE
(Ovid SP), PsycINFO (Ovid SP), CINAHL (EBSCOhost) and LILACS (BIREME).We also
searched the Database of Abstracts of Reviews of Effects (DARE) to identify
potentially relevant reviews. The search strategy was adapted for other
databases, using the most appropriate controlled vocabulary for each. We did not
apply any language or time restrictions. The searches were performed in August
2014.
SELECTION CRITERIA: We included randomised controlled trials (RCTs) of ETV
treatment of iNPH. Patients had to have at least two symptoms of the Hakim-Adams
triad. Exclusion criteria were obstructive causes of hydrocephalus, other
significant intracranial pathology and other confirmed causes of dementia. The
eligible comparators were conservative treatment or shunting using VP and VA
shunts.
DATA COLLECTION AND ANALYSIS: Two review authors independently screened search
results, selected eligible studies, assessed risk of bias and extracted data. We
contacted trial authors for additional data.
MAIN RESULTS: Only one study met the inclusion criteria: an RCT comparing
effectiveness of ETV and non-programmable VP shunts in 42 patients with iNPH.
The study was conducted in Brazil between 2009 and 2012. The overall study risk
of bias was high. The primary outcome in the study was the proportion of
patients with improved symptoms one year after surgery, determined as a change
of at least two points on the Japanese NPH scale. Due to imprecision in the
results, it was not possible to determine whether there was any difference
between groups in the proportion of patients who improved 3 or 12 months after
surgery (3 months: odds ration (OR) 1.12, 95% confidence interval (CI) 0.26 to
4.76, n = 42; 12 months: OR 2.5, 95% CI 0.62 to 10.11, n = 38). We were unable
to estimate the effect of treatment on other efficacy outcomes (cognition,
balance, function, gait and mobility) because they were inadequately reported.
Of the 26 patients in the VP shunting group, 5 developed subdural hematoma
postoperatively, while there were no complications among the 16 patients in the
ETV group (OR 0.12, 95% CI 0.01 to 2.3, n = 42), but the estimate was too
imprecise to determine whether this was likely to reflect a true difference in
complication rates. This was also the case for rates of further surgical
intervention (OR 1.4, 95% CI 0.31 to 6.24, n = 42). There were no deaths during
the trial. We judged the quality of evidence for all outcomes to be very low
because of a high risk of selection, attrition and reporting bias and serious
imprecision in the results.
AUTHORS' CONCLUSIONS: The only randomised trial of ETV for iNPH compares it to
an intervention which is not a standard practice (VP shunting using a
non-programmable valve). The evidence from this study is inconclusive and of
very low quality. Clinicians should be aware of the limitations of the evidence.
There is a need for more robust research on this topic to be able to determine
the effectiveness of ETV in patients with iNPH. |
Is the protein ABCG2 transmembrane? | Yes,
the protein ABCG2 is transmembrane. | An overexpression of the transmembrane ATP-binding cassette transporter G2
(ABCG2, BCRP) in cancer tissues is supposed to play a role in the multidrug
resistance (MDR) of tumors resulting in an inefficient chemotherapy. Therefore,
co-administration of selective and non-toxic ABCG2 inhibitors is a promising
strategy for improving the efficacy of chemotherapy by blocking ABCG2-mediated
export of the cytostatic drugs. In the present study, we designed a small
library of 38 novel compounds containing a heteroaryl-phenyl scaffold possessing
several (bioisosteric) moieties, and twelve new precursors. We investigated the
library for ABCG2 inhibition, for the selectivity against MDR-involved efflux
pump ABCB1 (P-gp) and for toxicity. Structure activity relationship (SAR)
studies revealed that, at least a phenylheteroaryl-phenylamide scaffold is
necessary for observing an ABCG2 inhibition.
4-Methoxy-N-(2-(2-(6-methoxypyridin-3-yl)-2H-tetrazol-5-yl)phenyl)benzamide (43)
exhibited a high potency (IC50 = 61 nM)), selectivity, low intrinsic toxicity
and reversed the ABCG2-mediated drug resistance in presence of only 0.1 μM. ATP-binding cassette (ABC) transporters are transmembrane efflux transporters
mediating the extrusion of an array of substrates ranging from amino acids and
lipids to xenobiotics, and many therapeutic compounds, including anticancer
drugs. The ABC transporters are also recognized as important contributors to
pharmacokinetics, especially in drug-drug interactions and adverse drug effects.
Drugs and xenobiotics, as well as pathologic conditions, can influence the
transcription of ABC transporters, or modify their activity or intracellular
localization. Kinases can affect the aforementioned processes for ABC
transporters as do protein interactions. In this review, we focus on the ABC
transporters ABCB1, ABCB11, ABCC1, ABCC4, and ABCG2 and illustrate how kinases
and protein-protein interactions affect these transporters. The clinical
relevance of these factors is currently unknown; however, these examples suggest
that our understanding of drug-drug interactions will benefit from further
knowledge of how kinases and protein-protein interactions affect ABC
transporters. The ATP-binding cassette (ABC) transporter family is a large class of ATP
energy-dependent transmembrane proteins, and its primary function is to use the
energy produced by ATP hydrolysis to transfer the substrate bound to the plasma
membrane. This family is also closely related to multidrug resistance (MDR) in
various diseases. Among the ABC transporter proteins, P-glycoprotein (P-gp),
multidrug resistance-associated protein (MRP) and breast cancer resistance
protein (BCRP) are the main members associated with MDR. At present, the roles
of these transporters in therapeutic failures have been extensively studied and
reviewed in cancer; however, they have rarely been described in autoimmune
diseases (AIDs). AID is a group of chronic inflammatory diseases of unknown
aetiology. AID's basic feature is the production of a large number of
autoantibodies, which leads to extensive damage to multiple systems and multiple
organs. Disease-modifying anti-rheumatic drugs (DMARDs) are commonly used in the
treatment of AID, but a considerable number of patients have no response or
develop resistance to these drugs over time. This phenomenon may be related to
the abnormal expression of the ABC transporter, which leads to a decrease in the
amount of drug entering cells that produce MDR. This article reviews the effects
of DMARDs on the expression and function of P-gp, MRPs, and BCRP and the related
molecular mechanism in the treatment of AID. |
Can radiotherapy cause radiation induced osteosarcoma? | Yes, Radiation-induced osteosarcomas are a recognized complication of radiation therapy. | The case of a patient with postirradiation osteosarcoma is presented. The
20-year-old female was diagnosed as having osteosarcoma by histological
examination of an open biopsy specimen. She underwent surgery for pure
dysgerminoma and received adjuvant postoperative radiotherapy, 40 Gy to the
pelvis and 30 Gy to the para-aortic region, 11 years ago. This case satisfied
the criteria for radiation-induced osteosarcoma proposed by Cahan et al.
Radiation-induced osteosarcoma is rare, but the possibility of that must be
borne in mind. Osteosarcomas arising in irradiated tissues are uncommon but important
complications of radiotherapy. Radiation-induced osteosarcomas generally occur
3-30 years after exposure and are most common after radiotherapy for cervical or
breast carcinoma. These tumors are usually rapidly growing, extremely painful,
and histologically high grade. In this paper, we report two cases of high-grade
post-radiation osteosarcoma of the scapula. Despite being almost identical
radiologically and pathologically, one case had a typical clinical presentation
whereas the second case had two unusual features, being non-painful and arising
in a field initially irradiated for bronchogenic carcinoma. In order to assess the role of genetic predisposition in the induction of
radiation-induced tumors, we performed statistical analysis on data from the
literature and from our own Institute with regard to the age at onset and the
latency period of osteosarcoma as the second primary tumor for retinoblastoma
with or without subsequent radiotherapy. In retinoblastoma survivors who
subsequently developed osteosarcoma, the age at onset of retinoblastoma was
young (average of 12 months) in both unilateral and bilateral forms. This
suggests that all or almost all of the patients were genetically predisposed by
a mutation of one allele of the RB1 gene. For retinoblastoma patients,
osteosarcomas occurred 1.2 years earlier inside than outside the radiation
field. The latency period between radiotherapy and osteosarcoma onset was 1.3
years shorter inside than outside the radiation field. Interestingly, a bimodal
distribution of latency periods was observed for osteosarcomas arising inside,
but not outside the radiation field: 40% occurred after a short latency, while
the latency of the remaining 60% was comparable to that of osteosarcoma
occurring outside the radiation field. This suggests that different mechanisms
may be involved in radiocarcinogenesis. A radiation-induced mutation of the
second RB1 allele may be the cause of osteosarcomas occurring after a short
delay, while other genes may be affected in those occurring after a longer
delay. A case of radiation-induced sarcoma of the chest wall is reported. Twenty-seven
years 11 months after orthovoltage radiotherapy of the right breast a
69-year-old woman developed a radiation-induced osteosarcoma of the right
thoracic wall. Initial diagnosis has been T-cell lymphoma of the skin. The right
breast was irradiated with tangential fields and a total dose of 40 Gy, 2
Gy/day, 5 days a week. Orthovoltage treatment was performed in two courses of 20
Gy, 3 months apart. The clinical appearance of the secondary sarcoma was a
diffuse infiltrated area in the irradiated breast which seemed to be fixed to
the chest wall. Magnetic resoce imaging (MRI) demonstrated a mass in the
right anterior thoracic wall which destroyed the fourth to the sixth rib. The
tumor infiltrated the thoracic wall, including subcutaneous tissue and
pericardium, as well as extending into the subphrenic space. Biopsy of the
lesion revealed a poorly differentiated osteosarcoma. The patient's general
condition precluded surgical or chemotherapeutic intervention; she died due to a
cerebral stroke 6 months later. This case fulfilled all criteria for
radiation-induced sarcoma, as there was a prior history of radiotherapy, latency
period of several years, development of sarcoma within the irradiated field, and
histologic confirmation of sarcoma. A 35-year-old man developed osteosarcoma of the left parietal and occipital
bones 16 years after radiotherapy for glioma in the right occipital lobe.
Radiotherapy of the primary neoplasm used 50 Gy administered to a localized
field through two lateral ports. The secondary neoplasm arose contralateral to
the primary lesion but within the irradiated field. The tumor had a multilocular
cyst with considerable intracranial extension, and symptoms of elevated
intracranial pressure were prominent early in the course. After a short-lived
initial remission following surgical intervention and chemotherapy, the patient
deteriorated because of tumor recurrence and died 18 months after the diagnosis.
Radiation-induced osteosarcoma is a well-known but rare complication of
radiotherapy for brain neoplasms with a poor prognosis. A 59-year-old woman underwent enucleation for choroidal melanoma. She had a late
recurrence of the melanoma, which was treated with surgery and radiotherapy.
Nine years after radiation treatment, she presented with pain and an orbital
mass. Biopsy of the mass revealed an osteoblastic osteosarcoma. This report
describes the late recurrence of choroidal melanoma and subsequent
radiation-induced osteosarcoma. The risk of radiation-induced maligcy should
be considered in all patients receiving radiotherapy. Despite yearly review,
osteosarcoma was diagnosed only when the patient had symptoms, thus raising
questions about the merits of long-term follow-up in detecting recurrence or
emergence of secondary tumors. Most radiation-induced osteosarcomas of the skull are reported to arise in the
facial bone or paranasal sinus after radiotherapy for retinoblastoma and/or
pituitary adenoma. Here we report two cases of radiation-induced osteosarcoma in
the paranasal sinus after treatment for frontal glioma. Case 1 was a 56-year-old
woman who underwent surgical resection of a left frontal tumor in October 1990.
The histological diagnosis was a low-grade glioma, and radiotherapy of 54 Gy was
administered. Sixteen years later, in September 2006, the patient noted an
enlarging subcutaneous mass in the right frontal region. CT showed an osteolytic
mass in the right frontal sinus. An open biopsy established the
histopathological diagnosis of osteosarcoma, and the patient subsequently died
of rapid tumor regrowth. Case 2 was a 58-year-old man who underwent partial
removal of a bifrontal tumor in May 1996. The histological diagnosis was
anaplastic oligoastrocytoma, and radiotherapy of 56 Gy was administered. Twelve
years later, in March 2008, the patient was readmitted to our hospital for
reasons of marked deterioration in general physical condition. Tumor recurrence
was suspected in the left frontal lobe, and CT demonstrated an osteolytic mass
in the left frontal and ethmoid sinus. A secondary operation was performed, and
the pathological specimens were diagnosed as osteosarcoma. Radiotherapy was
readministered, but the subject died of rapid tumor regrowth. From these
clinicopathological findings, both cases were diagnosed as radiation-induced
osteosarcoma. Radiation-induced osteosarcomas appeared 16 and 12 years after
radiotherapy in cases 1 and 2, respectively. As the prognosis of
radiation-induced osteosarcoma is poorer than that of primary osteo-sarcoma,
careful attention is required for consideration of the long-term survival of
patients with glioma. BACKGROUND: Although a rare complication of ionizing radiation,
radiation-induced osteosarcoma is now more frequently recognized as radiation
therapy has become common and cancer survival has increased. To date,
publications on radiation-induced osteosarcoma of the cranium are limited to a
few small series and case reports.
METHODS: Data from 175 patients with a history of sarcoma of the head at The
University of Texas M. D. Anderson Cancer Center from 1975 to 2007 were reviewed
to identify patients with radiation-induced osteosarcoma. The diagnostic
criteria were: 1) osteosarcoma arose within the previously irradiated field; 2)
new sarcoma was histologically distinct from the original neoplasm; 3) no
evidence of new sarcoma at the time of radiation; and 4) distinct latency period
could be recognized. Frequencies and descriptive statistics were obtained for
the various characteristics under study.
RESULTS: The authors identified 16 patients with radiation-induced osteosarcoma
of the cranium at their institution. The average age at diagnosis was 35 years.
The median latency period was 12.5 years. Nine patients had skull base tumors,
and 7 had calvarial tumors. Of the 14 patients treated surgically, 86% developed
local recurrence. The median survival time was 29 months, and the 5-year
survival rate was 29.6%.
CONCLUSIONS: The authors report the largest series of cranial radiation-induced
osteosarcoma. Although radiation-induced osteosarcoma is an uncommon but dire
complication of radiotherapy, its incidence will probably increase in the future
as the frequency of radiation treatment and cancer survival increase. These
tumors are locally aggressive, and despite aggressive surgical and medical
management, they have a high rate of local recurrence and mortality. Radiation therapy is frequently used method in treatment of the head and neck
maligcies. Osteosarcoma is a rare complication of radiation therapy and
usually occurs after a long latent period. We report the case of 75-year-old
female with osteosarcoma of the mastoid process. Twelve years before
presentation she received radiation therapy after total parotidectomy and
radical neck dissection in treatment of mucoepidermoid carcinoma of the parotid
gland. Diagnostic procedures included contrast-enhanced CT and MRI of the head
and neck and HRCT of the temporal bone. The final diagnosis of the low grade
osteosarcoma was confirmed by biopsy. Diagnostic criteria were fulfilled and the
lesion was classified as a radiation induced osteosarcoma. Low-grade extraskeletal osteosarcoma is a rare tumor that may arise de novo or
following radiation therapy. Because of the low-grade histology, it may be
misdiagnosed as a benign lesion. We present a case of a 59-year-old man with a
past history of radiotherapy for papillary carcinoma of the thyroid, presenting
16 years later with a low-grade extraskeletal osteosarcoma of the neck. The
patient was treated with surgical excision and is disease free after 12 months
of follow-up. The prognosis for patients with low-grade extraskeletal
osteosarcoma is relatively good when compared with high-grade sarcomas. While
there is a report of a low-grade extraskeletal osteosarcoma arising following
radiotherapy for a benign condition, to the best of our knowledge this is the
first reported case of a low-grade extraskeletal osteosarcoma occurring
following radiotherapy for thyroid cancer, and the only case reported in the
soft tissue of the head and neck region. Most radiation biologists/radiation oncologists have long accepted the concept
that the biologic effects of radiation principally involve damage to
deoxyribonucleic acid (DNA), which is the critical target, as described in
"Radiobiology for the Radiologist", by E.J. Hall and A.J. Giaccia [1]. Although
the concepts of direct and indirect effects of radiation are fully applicable to
low-LET (linear energy transfer) radioresistant tumor cells/normal tissues such
as osteosarcoma cells and chondrocytes, it is believed that radiation-associated
damage to DNA does not play a major role in the mechanism of cell death in
low-LET radiosensitive tumors/normal tissues such as maligt lymphoma cells
and lymphocytes. Hall and Giaccia describe lymphocytes as very radiosensitive,
based largely on apoptosis subsequent to irradiation. As described in this
review, apoptosis of lymphocytes and lymphoma cells is actually induced by the
"hydrogen peroxide (H₂O₂) effect", which I propose in this review article for
the first time. The mechanism of lymphocyte death via the H₂O₂ effect represents
an ideal model to develop the enhancement method of radiosensitivity for
radiation therapy of maligt neoplasms. In terms of imitating the high
radiosensitivity of lymphocytes, osteosarcoma cells (representative of low-LET
radioresistant cells) might be the ideal model for indicating the conversion of
cells from radioresistant to radiosensitive utilizing the H₂O₂ effect. External
beam radiation such as X-rays and high-energy electrons for use in modern
radiotherapy are generally produced using a linear accelerator. We theorized
that when tumors are irradiated in the presence of H₂O₂, the activities of
anti-oxidative enzymes such as peroxidases and catalase are blocked and oxygen
molecules are produced at the same time via the H₂O₂ effect, resulting in
oxidative damage to low-LET radioresistant tumor cells, thereby rendering them
highly sensitive to irradiation. In this review, this potential paradigm shift
in modern radiation biology/radiation oncology is discussed in detail in terms
of overcoming drug/radiation resistance in radiation therapy and/or anti-cancer
chemotherapy. BACKGROUND: The increasing incidence of radiation-induced osteosarcoma of the
maxilla and mandible (RIOSM) has become a significant problem that can limit
long-term survival. The purpose of this study was to analyze the association of
clinicopathologic characteristics with treatment outcomes and prognostic factors
of patients who developed RIOSM after undergoing radiotherapy for nasopharyngeal
carcinoma (NPC).
METHODS: We reviewed the medical records of 53,760 NPC patients admitted to Sun
Yat-sen University Cancer Center during the period August 1964 to August 2012.
Of these patients, 47 who developed RISOM and met inclusion criteria were
included in this study. Two of these 47 patients refused treatment and were then
excluded.
RESULTS: For all patients treated for NPC at Sun Yat-sen University Cancer
Center during the study period, the total incidence of RIOSM after radiotherapy
was 0.084% (47/53,760). Two patients (4.4%) had metastases at the diagnosis of
RIOSM. Thirty-nine of the 45 (86.7%) patients underwent surgery for RIOSM; most
patients (24/39; 61.5%) who underwent resection had gross clear margins, with 15
patients (38.5%) having either a gross or microscopic positive margin. All
patients died. The 1-, 2-, and 3-year overall survival (OS) rates for the entire
cohort of 45 patients were 53.3%, 35.6% and 13.5%, respectively. The independent
prognostic factors associated with high OS rate were tumor size and treatment
type.
CONCLUSIONS: RISOM after radiotherapy for NPC is aggressive and often eludes
early detection and timely intervention. Surgery combined with postoperative
chemotherapy might be an effective treatment to improve patient survival. We present a rare case of radiation-induced osteosarcoma following Gamma Knife®
surgery (GKS) for a vestibular schwannoma (VS). A 49-year-old female with
sporadic VS underwent GKS. Serial follow-up imaging showed that the tumor size
decreased. Six years after GKS, magnetic resoce imaging demonstrated regrowth
of the tumor. The tumor was removed via the retrosigmoid approach.
Interestingly, the final pathology report confirmed osteosarcoma arising in
schwannoma with direct transition (osteosarcoma component: 90 %, schwannoma
component: 10 %). The osteosarcoma was considered to be a radiation-induced
maligcy. The possibility of this rare complication should be explained to the
patient before GKS, and the patient should be screened periodically after GKS. Radiation-induced sarcomas are recognized complications of radiation therapy and
are associated with poor prognosis. Radiation-induced osteosarcoma is one of the
rare types of radiation-induced sarcomas, with the risk of radiation-induced
osteosarcomas being only 0.01%-0.03% among all patients treated with
radiotherapy. There have been only four reported cases of radiation-induced
osteosarcomas after radiotherapy for gliomas. Here, we report a unique case of
radiation-induced osteosarcomas arising on the skull and extending to the skin,
with a short latent period. We also review the clinical features of the
previously reported cases. |
What are manifestations of the Saint's Triad? | Saint's Triad includes hiatus hernia, gallstones, and diverticulosis coli. | A quarter of a century ago Professor C. F. M. Saint of the University of Cape
Town noted the occasional association of diverticular disease, hiatus hernia,
and gallstones in a patient. The occurrences of these diseases, and the
significance of their associations, are discussed. The suggestion is made that
the diseases are casually related to the consumption of fibre-depleted diets. The results are reported of a systematic research conducted on 684 patients
subjected to radiological examinations for the purpose of identifying the three
pathologies that constitute Saint's triad in an attempt to contribute to the
assessment of its real incidence. The investigation revealed 7 cases of Saint's
triad (1.02%) and 86 cases of bifocal associations; 59 cholelithiasis +
diverticulosis, 17 cholelithiasis + Hiatus hernia; 10 diverticulosis + hernia.
The incidence of the triad was 4 times higher than expected as was revealed by a
simple statistical calculation. The morphologic changes are described found in the gallbladder of a female
patient, aged 40; she had xanthogranulomatous cholecystitis secondary to
cholelithiasis combined with a hiatal hernia and multiple duodenal diverticulae
(Saint's triad). In connection with two cases authors review our current body of knowledge on
Saint's triad that means the concomitant occurrence of cholelithiasis, hiatus
hernia and colonic diverticulosis. Though each component of this syndrome is
fairly common, the Saint's triad is relatively seldom encountered. It does
happen so because not all the components are likely to cause clinical symptoms.
Consequently diagnosis and subsequent therapy are targeted at the dominating
symptoms. On the other hand, the existence of the syndrome is also not
sufficiently known in clinical practice. Authors stress that in the event of
simultaneous symptoms suggestive of atypic cholelithiasis, colonic
diverticulosis and hiatus hernia one has to consider a potential Saint's triad.
Therefore it is recommended to verify or exclude each of the three components to
establish a precise diagnosis and adequate subsequent therapy. We experienced two cases involving the simultaneous presence of cholelithiasis,
hiatal hernia, and umbilical hernia. Both patients were female and overweight
(body mass index of 25.0-29.9 kg/m(2)) and had a history of pregcy and
surgical treatment of cholelithiasis. Additionally, both patients had two of the
three conditions of Saint's triad. Based on analysis of the pathogenesis of
these two cases, we consider that these four diseases (Saint's triad and
umbilical hernia) are associated with one another. Obesity is a common risk
factor for both umbilical hernia and Saint's triad. Female sex, older age, and a
history of pregcy are common risk factors for umbilical hernia and two of the
three conditions of Saint's triad. Thus, umbilical hernia may readily develop
with Saint's triad. Knowledge of this coincidence is important in the clinical
setting. The concomitant occurrence of Saint's triad and umbilical hernia may be
another clinical "tetralogy." Yamanaka et al. described two case studies involving coexistent cholelithiasis,
hiatal hernia, and umbilical hernias, and discussed clinical similarities with
the classical features of the Saint's triad. Cholelithiasis, hiatal hernia, and
colonic diverticulosis characterize the classical triad, but some authors have
included any type of hernia due to herniosis-a developmental disorder of the
extracellular matrix. The main features of this triad, which seem to be
underdiagnosed and/or underreported, are discussed. Therefore, the commented
manuscript contributed to better understanding the scarcely reported condition. |
What is the mechanism of action of Erdafitinib? | Erdafitinib is an oral selective pan-fibroblast growth factor receptor (FGFR) tyrosine kinase inhibitor. | Fibroblast growth factor (FGF) signaling plays critical roles in key biological
processes ranging from embryogenesis to wound healing and has strong links to
several hallmarks of cancer. Genetic alterations in FGF receptor (FGFR) family
members are associated with increased tumor growth, metastasis, angiogenesis,
and decreased survival. JNJ-42756493, erdafitinib, is an orally active small
molecule with potent tyrosine kinase inhibitory activity against all four FGFR
family members and selectivity versus other highly related kinases. JNJ-42756493
shows rapid uptake into the lysosomal compartment of cells in culture, which is
associated with prolonged inhibition of FGFR signaling, possibly due to
sustained release of the inhibitor. In xenografts from human tumor cell lines or
patient-derived tumor tissue with activating FGFR alterations, JNJ-42756493
administration results in potent and dose-dependent antitumor activity
accompanied by pharmacodynamic modulation of phospho-FGFR and phospho-ERK in
tumors. The results of the current study provide a strong rationale for the
clinical investigation of JNJ-42756493 in patients with tumors harboring FGFR
pathway alterations. Mol Cancer Ther; 16(6); 1010-20. ©2017 AACR. Findings from a phase II study indicate clinical efficacy with erdafitinib in
patients with FGFR-altered inoperable or metastatic urothelial carcinoma. Robust
responses were seen with this investigational pan-FGFR inhibitor, including in
patients who did not respond to prior immunotherapy. Small-molecule inhibitors (nibs) have revolutionized cancer therapy with the
emergence of clinically efficacious treatment for advanced-stage maligcies.
Fibroblast growth factor receptor (FGFR) inhibitors have shown therapeutic
efficacy in maligcies with molecular-genetic alterations in the
FGFR/fibroblast growth factor pathway. In a phase 1 clinical trial, erdafitinib,
a pan FGFR inhibitor, was well tolerated with a manageable toxicity profile.
Hyperphosphatemia was a frequent adverse event in patients treated with
erdafitinib; however, no serious complications were observed with this therapy.
Here, we report the development of calcinosis cutis dermatologic toxicity in a
patient with hyperphosphatemia while treated with a novel selective FGFR
inhibitor, INCB 54828-101. Awareness of this form of dermatologic toxicity from
an FGFR inhibitor will be important for close monitoring of serum levels of
phosphate, FGF23, vitamin D, and calcitriol, the management of adverse serum
chemistry with chelators, and treatment decisions to either reduce dose or
withhold FGFR inhibitor. Colorectal cancer (CRC) is the third cause of cancer-related mortality in
industrialized countries. Local invasion and metastasis formation are events
associated with poor prognosis for which today there are no effective
therapeutic options. Invasion and metastasis are strongly modulated by cells of
the tumor microenvironment (TME), in particular fibroblasts and endothelial
cells. Unraveling interactions between tumor cells and cells of the TME may
identify novel mechanisms and therapeutic targets to prevent or treat
metastasis. We report here the development and in vivo validation of a 3D tumor
spheroid model to study the interactions between CRC cells, fibroblasts and
endothelial cells in vitro. Co-cultured fibroblasts promoted SW620 and HCT116
CRC spheroid invasion, and this was prevented by the SRC and FGFR kinase
inhibitors Dasatinib and Erdafitinib, respectively. To validate these findings
in vivo, we injected SW620 cells alone or together with fibroblasts
orthotopically in the caecum of mice. Co-injection with fibroblasts promoted
lung metastasis growth, which was fully reversed by treatment with Dasatinib or
Erdafitinib. Co-culture of SW620 or HCT116 CRC spheroids with endothelial cells
suppressed spheroid growth while it had no effect on cancer cell migration or
invasion. Consistent with this in vitro effect, co-injected endothelial cells
significantly inhibited primary tumor growth in vivo. From these experiments we
conclude that effects on cancer cell invasion and growth induced by co-cultured
TME cells and drug treatment in the 3D spheroid model in vitro, are predictive
of in vivo effects. The 3D spheroid model may be considered as an attractive
model to study the effect of heterotypic cellular interactions and drug
activities on cancer cells, as animal testing alternative. This model may be
adapted and further developed to include different types of cancer and host
cells and to investigate additional functions and drugs. PURPOSE: Here, we report results of the first phase I study of erdafitinib, a
potent, oral pan-FGFR inhibitor.
PATIENTS AND METHODS: Patients age ≥18 years with advanced solid tumors for
which standard antineoplastic therapy was no longer effective were enrolled
(NCT01703481). Parts 2 to 4 employed molecular screening for activating FGFR
genomic alterations. In patients with such alterations, two selected
doses/schedules identified during part 1 dose-escalation [9 mg once daily and 10
mg intermittently (7 days on/7 days off), as previously published (Tabernero JCO
2015;33:3401-8)] were tested.
RESULTS: The study included 187 patients. The most common treatment-related
adverse events were hyperphosphatemia (64%), dry mouth (42%), and asthenia
(28%), generally grade 1/2 severity. All cases of hyperphosphatemia were grade
1/2 except for 1 grade 3 event. Skin, nail, and eye changes were observed in
43%, 33%, and 28% of patients, respectively (mostly grade 1/2 and reversible
after temporary dosing interruption). Urothelial carcinoma and
cholangiocarcinoma were most responsive to erdafitinib, with objective response
rates (ORR) of 46.2% (12/26) and 27.3% (3/11), respectively, in
response-evaluable patients with FGFR mutations or fusions. All patients with
urothelial carcinoma and cholangiocarcinoma who responded to erdafitinib carried
FGFR mutations or fusions. Median response duration was 5.6 months for
urothelial carcinoma and 11.4 months for cholangiocarcinoma. ORRs in other tumor
types were <10%.
CONCLUSIONS: Erdafitinib shows tolerability and preliminary clinical activity in
advanced solid tumors with genomic changes in the FGFR pathway, at two different
dosing schedules and with particularly encouraging responses in urothelial
carcinoma and cholangiocarcinoma. BACKGROUND: Alterations in the gene encoding fibroblast growth factor receptor
(FGFR) are common in urothelial carcinoma and may be associated with lower
sensitivity to immune interventions. Erdafitinib, a tyrosine kinase inhibitor of
FGFR1-4, has shown antitumor activity in preclinical models and in a phase 1
study involving patients with FGFR alterations.
METHODS: In this open-label, phase 2 study, we enrolled patients who had locally
advanced and unresectable or metastatic urothelial carcinoma with prespecified
FGFR alterations. All the patients had a history of disease progression during
or after at least one course of chemotherapy or within 12 months after
neoadjuvant or adjuvant chemotherapy. Prior immunotherapy was allowed. We
initially randomly assigned the patients to receive erdafitinib in either an
intermittent or a continuous regimen in the dose-selection phase of the study.
On the basis of an interim analysis, the starting dose was set at 8 mg per day
in a continuous regimen (selected-regimen group), with provision for a
pharmacodynamically guided dose escalation to 9 mg. The primary end point was
the objective response rate. Key secondary end points included progression-free
survival, duration of response, and overall survival.
RESULTS: A total of 99 patients in the selected-regimen group received a median
of five cycles of erdafitinib. Of these patients, 43% had received at least two
previous courses of treatment, 79% had visceral metastases, and 53% had a
creatinine clearance of less than 60 ml per minute. The rate of confirmed
response to erdafitinib therapy was 40% (3% with a complete response and 37%
with a partial response). Among the 22 patients who had undergone previous
immunotherapy, the confirmed response rate was 59%. The median duration of
progression-free survival was 5.5 months, and the median duration of overall
survival was 13.8 months. Treatment-related adverse events of grade 3 or higher,
which were managed mainly by dose adjustments, were reported in 46% of the
patients; 13% of the patients discontinued treatment because of adverse events.
There were no treatment-related deaths.
CONCLUSIONS: The use of erdafitinib was associated with an objective tumor
response in 40% of previously treated patients who had locally advanced and
unresectable or metastatic urothelial carcinoma with FGFR alterations.
Treatment-related grade 3 or higher adverse events were reported in nearly half
the patients. (Funded by Janssen Research and Development; BLC2001
ClinicalTrials.gov number, NCT02365597.). Introduction: Fibroblast growth-factor receptor (FGFR) inhibition is a promising
strategy of treatment in urothelial cancer (UC). FGFR3 mutations or fusions
(mut/fus) are common in luminal-1 UC subtype, which exhibits poor responses to
immunotherapy. Erdafitinib is a potent and selective pan-FGFR tyrosine kinase
inhibitor. Based on the results of the phase 2 BLC2001 trial (NCT02365597), in
which erdafitinib showed an overall response rate of 40% in metastatic UC with
FGFR3 mut/fus, it is the first approved targeted therapy in metastatic UC. Areas
covered: This review covers the preclinical and clinical evidence for
erdafitinib, summarizes the results of other FGFR inhibitors tested in UC and
explores future perspectives of FGFR inhibition in UC. Expert opinion: In the
era of precision medicine, erdafitinib approval marks a step forward in UC.
Erdafitinib qualifies as a compelling comparator in the salvage therapy setting.
Special attention must be paid to typical adverse class-effects of FGFR
inhibitors. In the near future, in order to achieve an optimal selection of
molecularly-altered tumors, it will be important to assess the performance of
different diagnostic tools and to investigate the role of liquid biopsy.
Combinations with immunotherapy represent a novel therapeutic opportunity being
tested in ongoing trials. Erdafitinib, a potent oral fibroblast growth factor receptor inhibitor, is a low
extraction ratio drug highly bound to alpha-1-acid glycoprotein (AGP) with free
fraction (fu ) varying across populations. This analysis aimed to characterize
the impact of plasma protein binding on erdafitinib pharmacokinetics (PK).
Plasma protein-binding data (fu , AGP, albumin) and PK parameters were pooled
from 6 phase 1 studies in healthy participants and 1 first-in-human study in
patients with cancer. Binding kinetics were characterized using a nonlinear
mixed-effects model. Mean (coefficient of variation, CV%) fu was 0.510% (39.4%)
for healthy participants and 0.316% (64.0%) for patients, with a 2.1-fold higher
AGP and 10% lower albumin. Linear binding of erdafitinib to AGP and albumin was
observed, with >1000-fold higher binding constant for AGP than albumin (17.6 vs
0.017 µM-1 ). The fu decreased with increasing AGP in a nonlinear relationship.
Despite its abundance in plasma relative to AGP, albumin contributed to <4% of
the overall binding of erdafitinib (1.8% in patients; 4.0% in healthy
participants). The AGP-binding constant was 68.0% lower in predose (spiked)
versus postdose (ex vivo) samples. Total oral clearance was generally
proportional to the fu and higher in healthy participants than in patients,
consistent with the differences in AGP. Correcting for fu accounted for the
majority of the relationship between oral clearance and fu as expected with a
low extraction ratio drug. Characterizing free erdafitinib concentrations is
critical to accounting for differences in fu and to further investigating its
clinical relevance. BACKGROUND AND OBJECTIVES: Erdafitinib, an oral selective pan-fibroblast growth
factor receptor (FGFR) kinase inhibitor, is primarily metabolized by cytochrome
P450 (CYP) 2C9 and 3A4. The aim of this phase 1 study was to assess the
pharmacokinetics and safety of erdafitinib in healthy participants when
coadministered with fluconazole (moderate CYP2C9 and CYP3A inhibitor), and
itraconazole (a strong CYP3A4 and P-glycoprotein inhibitor). The effect of
CYP2C9 genotype variants (*1/*1, *1/*2, *1/*3) on the pharmacokinetics of
erdafitinib was also investigated.
METHODS: In this open-label, parallel-group, single-center study, eligible
healthy adults were randomized by CYP2C9 genotype to receive Treatment A (single
oral dose of erdafitinib 4 mg) on day 1, Treatment B (fluconazole 400 mg/day
orally) on days 1-11, or Treatment C (itraconazole 200 mg/day orally) on days
1-11. Healthy adults randomized to Treatment B and C received a single oral 4-mg
dose of erdafitinib on day 5. The pharmacokinetic parameters, including mean
maximum plasma concentration (Cmax), area under the curve (AUC) from time 0 to
168 h (AUC168h), AUC from time 0 to the last quantifiable concentration
(AUClast), and AUC from time 0 to infinity (AUC∞) were calculated from
individual plasma concentration-time data using standard non-compartmental
methods.
RESULTS: Coadministration of erdafitinib with fluconazole increased Cmax of
erdafitinib by approximately 21%, AUC168h by 38%, AUClast by 49%, and AUC∞ by
48% while coadministration with itraconazole resulted in no change in
erdafitinib Cmax and increased AUC168h by 20%, AUClast by 33% and AUC∞ by 34%.
Erdafitinib exposure was comparable between participants with CYP2C9 *1/*2 or
*1/*3 and with wild-type CYP2C9 genotype. The ratio of total amount of
erdafitinib excreted in the urine (inhibited to non-inhibited) was 1.09, the
ratio of total amount of excreted metabolite M6 was 1.21, and the ratio of the
metabolite to parent ratio in the urine was 1.11, when coadministration of
erdafitinib with itraconazole was compared with single-dose erdafitinib.
Treatment-emergent adverse events (TEAEs) were generally Grade 1 or 2 in
severity; the most commonly reported TEAE was headache. No safety concerns were
identified with single-dose erdafitinib when administered alone and in
combination with fluconazole or itraconazole in healthy adults.
CONCLUSION: Coadministration of fluconazole or itraconazole or other
moderate/strong CYP2C9 or CYP3A4 inhibitors may increase exposure to erdafitinib
in healthy adults and thus may warrant erdafitinib dose reduction or use of
alternative concomitant medications with no or minimal CYP2C9 or CYP3A4
inhibition potential.
TRIAL REGISTRATION: ClinicalTrials.gov identifier number: NCT03135106. The human fibroblast growth factor family consists of 22 factors and five
transmembrane receptors. Of the 22 factors, eighteen are secreted while four of
them function exclusively within the cell. Four of the fibroblast growth factor
receptors (FGFRs) possess intracellular protein-tyrosine kinase activity while
the fifth (FGFRL1) has a short 105-residue intracellular non-enzymatic
component. The FGFR protein kinase domain consists of a bi-lobed structure that
is similar to that of all other protein kinases. FGFR gene alterations occur in
a wide variety of cancers including those of the urinary bladder, breast, ovary,
prostate, endometrium, lung, and stomach. The majority (66 %) of FGFR gene
alterations involve gene amplifications, followed by mutations (26 %), and
rearrangements that produce fusion proteins (8 %). Erdafitinib was the first
orally effective FGFR antagonist approved by the FDA (2019) for the treatment of
advanced cancer, that of the urinary bladder. FGF23 suppresses phosphate
reabsorption in the proximal tubules of the kidney; FGF23 blockade allows
phosphate reabsorption to occur and leads to elevated serum phosphate levels.
Erdafitinib and several other, but not all, FGFR antagonists produce
hyperphosphatemia. Erdafitinib binds to an inactive DGF-Din conformation of
FGFR1 and is classified as a type I½ inhibitor. Similarly, dovitinib, AZD4547,
CH5183284, infigratinib, lenvatinib, LY2874455, and lucitanib are type I½
inhibitors. The inactive conformations contain an autoinhibitory brake that is
made up of three main residues: an asparagine (N) within the αC-β4 back loop, a
glutamate (E) corresponding to the second hinge residue, and a lysine (K) in the
β8-strand (the NEK triad). PDGFRα/β, Kit, CSF1R, VEGFR1/2/3, Flt3, Tek, and Tie
protein kinases are also regulated by a similar autoinhibitory brake mechanism.
Ponatinib binds to FGFR4 in a DFG-Dout conformation and is classified as a type
II inhibitor. Futibatinib, roblitinib, H3B-6527, fisogatinib, and PRN1371 bind
covalently to their FGFR target and are classified as type VI inhibitors.
Nintedanib, pazopanib, pemigatinib, rogaratinib, fisogatinib, and PRN1371 are
FGFR inhibitors lacking drug-enzyme crystal structures. All of the
aforementioned FGFR antagonists are orally effective. The development of FGFR
inhibitors has lagged behind those of other receptor protein-tyrosine kinases.
However, the FDA approval of erdafitinib for the treatment of urinary bladder
cancers may stimulate additional work targeting the many other FGFR-driven
neoplasms. |
Are male or female persons more prone to autoimmunity? | Sex hormones have long been implicated in autoimmune diseases because women account for 80% of cases. | BACKGROUND: The sexually dimorphic prevalence of autoimmune disease remains one
of the most intriguing clinical observations among this group of disorders.
While sex hormones have long been recognized for their roles in reproductive
functions, within the past 2 decades scientists have found that sex hormones are
integral signaling modulators of the mammalian immune system. Sex hormones have
definitive roles in lymphocyte maturation, activation, and synthesis of
antibodies and cytokines. Sex hormone expression is altered among patients with
autoimmune disease, and this variation of expression contributes to immune
dysregulation.
OBSERVATIONS: English-language literature from the last 10 years was reviewed to
examine the relationship between sex hormones and the function of the mammalian
immune system. Approximately 50 publications were included in this review, and
the majority were controlled trials with investigator blinding that compared
both male and female diseased and normal subjects. The review provided basic
knowledge regarding the broad impact of sex hormones on the immune system and
how abnormal sex hormone expression contributes to the development and
maintece of autoimmune phenomena, with a focus on systemic lupus
erythematosus, as models of "lupus-prone" mice are readily available.
CONCLUSIONS: Sex hormones affect the function of the mammalian immune system,
and sex hormone expression is different in patients with systemic lupus
erythematosus than in healthy subjects. Sex hormones play a role in the genesis
of autoimmunity. Future research may provide a therapeutic approach that is
capable of altering disease pathogenesis, rather than targeting disease
sequelae. Sex hormones have long been implicated in autoimmune diseases because women
account for 80% of cases. The mechanism of hormonal action in autoimmunity is
unknown. Drawing on genetic studies of autoimmune disease, this article
discusses how both genes and sex hormones may exert their effects through the
same general mechanism, dysregulation of transcription factor NF-kappaB, an
immunoregulatory protein. Gene and hormone alterations of the NF-kappaB
signaling cascade provide a unifying hypothesis to explain the wide-ranging
human and murine autoimmune disease phenotypes regulated by NF-kappaB, including
cytokine balance, antigen presentation, lymphoid development, and lymphoid
repertoire selection by apoptosis. The number of human conditions that are currently considered to be autoimmune
diseases (AID) has been steadily growing over the past decades and it is now
estimated that over 10 million people are affected in the United States. One of
the major shared features among AID is the predomice in the female sex which
in some cases changes with the age at disease diagnosis. Numerous hypotheses
have been formulated based on intuitive scientific backgrounds to justify this
sex imbalance, i.e. sex hormones and reproductive factors, fetal microchimerism,
other sex-related environmental factors, a skewing of the X-chromosome
inactivation patterns, and major defects in sex chromosomes. Nevertheless, none
of these hypotheses has thus far gathered enough convincing evidence and in most
cases data are conflicting, as well illustrated by the reports on fetal
microchimerism in systemic sclerosis or primary biliary cirrhosis. The present
article will critically discuss the main hypotheses (loss of mosaicism,
reactivation, and haploinsufficiency) that have been proposed based on findings
in female patients with specific AID along with two additional mechanisms
(X-chromosome vulnerability and X-linked polyamine genes) that have been
observed in AID models. Further, recent data have significantly shifted the
paradigm of X chromosome inactivation by demonstrating that a large number of
genes can variably escape silencing on one or both chromosomes. As a result we
may hypothesize that more than one mechanism may contribute to the female
susceptibility to tolerance breakdown while the possibility that unknown factors
may indeed protect men from AID should not be overlooked. Autoimmune diseases like rheumatoid arthritis are multifactorial in nature,
requiring both genetic and environmental factors for onset. Increased
predisposition of females to a wide range of autoimmune diseases points to a
gender bias in the multifactorial etiology of these disorders. However, the
existing evidence to date has not provided any conclusive mechanism of
gender-bias beyond the role of hormones and sex chromosomes. The gut microbiome,
which impacts the innate and adaptive branches of immunity, not only influences
the development of autoimmune disorders but may interact with sex-hormones to
modulate disease progression and sex-bias. Here, we review the current
information on gender bias in autoimmunity and discuss the potential of
microbiome-derived biomarkers to help unravel the complex interplay between
genes, environment and hormones in rheumatoid arthritis. |
Which is the phenotype of the disease fibrodysplasia ossificans progressiva? | Fibrodysplasia ossificans progressiva (FOP), a congenital heterotopic ossification (HO) syndrome caused by gain-of-function mutations of bone morphogenetic protein (BMP) type I receptor ACVR1, manifests with progressive ossification of skeletal muscles, tendons, ligaments, and joints. | OBJECTIVE: Fibrodysplasia ossificans progressiva (FOP) is an ultra-rare genetic
disorder in which heterotopic bone forms in the soft tissues. This often occurs
in response to injury or inflammation, leading to joint immobilization and
significant disability. There are currently no definitive treatment options for
this devastating disease. Although the most dramatic phenotype in FOP is the
episodic and progressive heterotopic ossification, patients report a number of
symptoms that affect other organ systems. Post-mortem examination of FOP
patients may contribute to our understanding of the underlying pathophysiology
and complications of this disease. Here, we present the autopsy findings from
three patients with FOP.
FINDINGS: Autopsy findings in two of the three patients confirmed that the cause
of death was cardiorespiratory failure in the setting of severe thoracic
insufficiency from heterotopic ossification. Both of these patients also had
evidence of right ventricular dilatation likely secondary to thoracic
insufficiency. The third patient died from complications of a traumatic head
injury after a fall but also had post-mortem evidence of thoracic insufficiency
syndrome. All three patients had extensive, widespread heterotopic ossification
and joint deformities consistent with FOP. There was extensive ossification of
the spinal ligament in these patients, which may contribute to cervical spine
rigidity. One patient was diagnosed post-mortem with a brainstem malformation.
No additional significant abnormalities were noted in the other organ systems.
Finally, we also demonstrate that cadaveric skin fibroblasts can be isolated for
use as a potential source for future in vitro cell culture studies.
CONCLUSIONS: This autopsy case series provides valuable information about the
underlying complications of FOP and contributes significantly to our knowledge
of this rare yet debilitating disorder. Thoracic insufficiency syndrome, right
heart dysfunction, widespread heterotopic ossification, spinal ligament
ossification, and CNS malformations were clearly evident; however, most other
non-bone tissues appeared to be spared from gross malformations. Finally, the
ability to isolate live cells from cadaveric skin is an important technique that
will facilitate future studies, particularly as induced pluripotent stem cells
and other cell-based technologies evolve. This case series highlights the
importance of post-mortem examinations and their contribution to our current
knowledge of disease pathophysiology and comorbidities. |
Are lamina-associated domains (LADs) associated with transcriptional activation? | Regions of focal DNA hypermethylation and long-range hypomethylation in colorectal cancer coincide with nuclear lamina-associated domains. Such lamina-associated domains (LADs) are thought to help organize chromosomes inside the nucleus and have been associated with gene repression. | Author information:
(1)Division of Gene Regulation, Netherlands Cancer Institute, 1066 CX Amsterdam,
the Netherlands; Department of Cell Biology, Erasmus University Medical Center,
3015 CE Rotterdam, the Netherlands. Electronic address: [email protected].
(2)Department of Cell and Developmental Biology, University of Illinois at
Urbana-Champaign, Urbana, IL 61801, USA; Carl R. Woese Institute for Genomic
Biology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA.
Electronic address: [email protected]. The nuclear lamina contributes to the regulation of gene expression and to
chromatin organization. Mutations in A-type nuclear lamins cause laminopathies,
some of which are associated with a loss of heterochromatin at the nuclear
periphery. Until recently however, little if any information has been provided
on where and how lamin A interacts with the genome and on how disease-causing
lamin A mutations may rearrange genome conformation. Here, we review aspects of
nuclear lamin association with the genome. We highlight recent evidence of
reorganization of lamin A-chromatin interactions in cellular models of
laminopathies, and implications on the 3-dimensional rearrangement of chromatin
in these models, including patient cells. We discuss how a hot-spot
lipodystrophic lamin A mutation alters chromatin conformation and epigenetic
patterns at an anti-adipogenic locus, and conclude with remarks on links between
lamin A, Polycomb and the pathophysiology of laminopathies. The recent findings
presented here collectively argue towards a deregulation of large-scale and
local spatial genome organization by a subset of lamin A mutations causing
laminopathies. |
Is Hemochromatosis type 4 is caused by a mutation in a recessive gene? | No, Hemochromatosis type 4 is caused by an autosomal dominant gene | Hemochromatosis type 4 is a rare form of primary iron overload transmitted as an
autosomal domit trait caused by mutations in the gene encoding the iron
transport protein ferroportin 1 (SLC40A1). SLC40A1 mutations fall into two
functional categories (loss- versus gain-of-function) underlying two distinct
clinical entities (hemochromatosis type 4A versus type 4B). However, the vast
majority of SLC40A1 mutations are rare missense variations, with only a few
showing strong evidence of causality. The present study reports the results of
an integrated approach collecting genetic and phenotypic data from 44 suspected
hemochromatosis type 4 patients, with comprehensive structural and functional
annotations. Causality was demonstrated for 10 missense variants, showing a
clear dichotomy between the two hemochromatosis type 4 subtypes. Two subgroups
of loss-of-function mutations were distinguished: one impairing cell-surface
expression and one altering only iron egress. Additionally, a new
gain-of-function mutation was identified, and the degradation of ferroportin on
hepcidin binding was shown to probably depend on the integrity of a large
extracellular loop outside of the hepcidin-binding domain. Eight further
missense variations, on the other hand, were shown to have no discernible
effects at either protein or RNA level; these were found in apparently isolated
patients and were associated with a less severe phenotype. The present findings
illustrate the importance of combining in silico and biochemical approaches to
fully distinguish pathogenic SLC40A1 mutations from benign variants. This has
profound implications for patient management. Mutations of SLC40A1 encoding ferroportin (Fpn), the unique cellular iron
exporter, severely affect iron homeostasis causing type 4 hereditary
hemochromatosis, an autosomal domit iron overload condition with variable
phenotypic manifestations. This disease can be classified as type 4A, better
known as "ferroportin disease", which is due to "loss of function" mutations
that lead to decreased iron export from cells, or as type 4B hemochromatosis,
which is caused by "gain of function" mutations, conferring partial or complete
resistance to hepcidin-mediated Fpn degradation. In this work, we discuss
clinical and molecular findings on a group of patients in whom a SLC40A1 single
copy missense variant was identified. Three novel variants, p.D181N, p.G204R and
p.R296Q were functionally characterized. Fpn D181N and R296Q mutants can be
classified as full or partial loss of function, respectively. Replacement of
G204 with arginine appears to cause a more complex defect with impact both on
iron export function and hepcidin sensitivity. This finding confirms the
difficulty of predicting the effect of a mutation on the molecular properties of
Fpn in order to provide an exhaustive explanation to the wide variability of the
phenotype in type 4 hereditary hemochromatosis. BACKGROUND & AIMS: Haemochromatosis type 4, also known as ferroportin disease,
is an autosomal domit genetic disorder caused by pathogenic mutations in the
SLC40A1 gene, which encodes ferroportin 1 (FPN1). We have identified a novel
SLC40A1 p.Y333H mutation in our previous study. In the present study, we tried
to investigate the frequency and pathogenicity of the SLC40A1 p.Y333H mutation
in haemochromatosis in China.
METHODS: Patients were analysed for SLC40A1 p.Y333H as well as mutations in the
other classic haemochromatosis-related genes by Sanger sequencing. To analyse
iron export capacity of the SLC40A1 p.Y333H mutant, the 293T cells were
transfected with the SLC40A1 p.Y333H construct and then treated with hepcidin
after exposure to ferric ammonium citrate. Cellular localization of mutant FPN1,
expression of FPN1 and intracellular ferritin were analysed by
immunofluorescence and Western blotting.
RESULTS: Of 22 unrelated cases with primary iron overload, three cases (3/22,
13.6%) harboured the SLC40A1 p.Y333H, with no missense mutations identified in
any other classical haemochromatosis-related genes including HFE, HJV, HAMP and
TFR2. Pedigree analysis showed that three probands and the son of one proband
had haemochromatosis of stage 3, while the son of another proband with age of 16
showed elevated transferrin saturation but normal serum ferritin level. In vitro
studies showed the mutant p.Y333H ferroportin was resistant to hepcidin,
affecting the subsequent internalization and degradation of FPN1, and was
associated with ferroportin gain of function.
CONCLUSIONS: The SLC40A1 p.Y333H mutation is associated with gain of function of
ferroportin, representing one of the major aetiological factors of
haemochromatosis in China. |
What is the purpose of the LINCS Project? | The Library of Integrated Network-Based Cellular Signatures (LINCS) project aims to create a network-based understanding of biology by cataloging changes in gene expression and signal transduction that occur when cells are exposed to a variety of perturbations. | The National Institutes of Health Library of Integrated Network-based Cellular
Signatures (LINCS) program is generating extensive multidimensional data sets,
including biochemical, genome-wide transcriptional, and phenotypic cellular
response signatures to a variety of small-molecule and genetic perturbations
with the goal of creating a sustainable, widely applicable, and readily
accessible systems biology knowledge resource. Integration and analysis of
diverse LINCS data sets depend on the availability of sufficient metadata to
describe the assays and screening results and on their syntactic, structural,
and semantic consistency. Here we report metadata specifications for the most
important molecular and cellular components and recommend them for adoption
beyond the LINCS project. We focus on the minimum required information to model
LINCS assays and results based on a number of use cases, and we recommend
controlled terminologies and ontologies to annotate assays with syntactic
consistency and semantic integrity. We also report specifications for a simple
annotation format (SAF) to describe assays and screening results based on our
metadata specifications with explicit controlled vocabularies. SAF specifically
serves to programmatically access and exchange LINCS data as a prerequisite for
a distributed information management infrastructure. We applied the metadata
specifications to annotate large numbers of LINCS cell lines, proteins, and
small molecules. The resources generated and presented here are freely
available. The Library of Integrated Network-Based Cellular Signatures (LINCS) project aims
to create a network-based understanding of biology by cataloging changes in gene
expression and signal transduction that occur when cells are exposed to a
variety of perturbations. It is helpful for understanding cell pathways and
facilitating drug discovery. Here, we developed a novel approach to infer
cell-specific pathways and identify a compound's effects using gene expression
and phosphoproteomics data under treatments with different compounds. Gene
expression data were employed to infer potential targets of compounds and create
a generic pathway map. Binary linear programming (BLP) was then developed to
optimize the generic pathway topology based on the mid-stage signaling response
of phosphorylation. To demonstrate effectiveness of this approach, we built a
generic pathway map for the MCF7 breast cancer cell line and inferred the
cell-specific pathways by BLP. The first group of 11 compounds was utilized to
optimize the generic pathways, and then 4 compounds were used to identify
effects based on the inferred cell-specific pathways. Cross-validation indicated
that the cell-specific pathways reliably predicted a compound's effects.
Finally, we applied BLP to re-optimize the cell-specific pathways to predict the
effects of 4 compounds (trichostatin A, MS-275, staurosporine, and digoxigenin)
according to compound-induced topological alterations. Trichostatin A and MS-275
(both HDAC inhibitors) inhibited the downstream pathway of HDAC1 and caused cell
growth arrest via activation of p53 and p21; the effects of digoxigenin were
totally opposite. Staurosporine blocked the cell cycle via p53 and p21, but also
promoted cell growth via activated HDAC1 and its downstream pathway. Our
approach was also applied to the PC3 prostate cancer cell line, and the
cross-validation analysis showed very good accuracy in predicting effects of 4
compounds. In summary, our computational model can be used to elucidate
potential mechanisms of a compound's efficacy. The Library of Integrated Cellular Signatures (LINCS) project provides
comprehensive transcriptome profiling of human cell lines before and after
chemical and genetic perturbations. Its L1000 platform utilizes 978 landmark
genes to infer the transcript levels of 14,292 genes computationally. Here we
conducted the L1000 data quality control analysis by using MCF7, PC3, and A375
cell lines as representative examples. Before perturbations, a promising 80%
correlation in transcriptome was observed between L1000- and Affymetrix
HU133A-platforms. After library-based shRNA perturbations, a moderate 30% of
differentially expressed genes overlapped between any two selected controls
viral vectors using the L1000 platform. The mitogen-activated protein kinase,
vascular endothelial growth factor, and T-cell receptor pathways were identified
as the most significantly shared pathways between chemical and genetic
perturbations in cancer cells. In conclusion, L1000 platform is reliable in
assessing transcriptome before perturbation. Its response to perturbagens needs
to be interpreted with caution. A quality control analysis pipeline of L1000 is
recommended before addressing biological questions. Drug repositioning strategies have improved substantially in recent years. At
present, two advances are poised to facilitate new strategies. First, the LINCS
project can provide rich transcriptome data that reflect the responses of cells
upon exposure to various drugs. Second, machine learning algorithms have been
applied successfully in biomedical research. In this paper, we developed a
systematic method to discover novel indications for existing drugs by
approaching drug repositioning as a multi-label classification task and used a
Softmax regression model to predict previously unrecognized therapeutic
properties of drugs based on LINCS transcriptome data. This approach to complete
the said task has not been achieved in previous studies. By performing in silico
comparison, we demonstrated that the proposed Softmax method showed markedly
superior performance over those of other methods. Once fully trained, the method
showed a training accuracy exceeding 80% and a validation accuracy of
approximately 70%. We generated a highly credible set of 98 drugs with high
potential to be repositioned for novel therapeutic purposes. Our case studies
included zonisamide and brinzolamide, which were originally developed to treat
indications of the nervous system and sensory organs, respectively. Both drugs
were repurposed to the cardiovascular category. |
Can Patient-derived organoids (PDOs) recapitulate patient responses in the clinic? | Yes. Phenotypic and genotypic profiling of PDOs showed a high degree of similarity to the original patient tumors. Molecular profiling of tumor organoids was matched to drug-screening results, suggesting that PDOs could complement existing approaches in defining cancer vulnerabilities and improving treatment responses. In summary, PDOs can recapitulate patient responses in the clinic and could be implemented in personalized medicine programs. | Pancreatic ductal adenocarcinoma (PDAC) has the worst prognosis among solid
maligcies and improved therapeutic strategies are needed to improve outcomes.
Patient-derived xenografts (PDX) and patient-derived organoids (PDO) serve as
promising tools to identify new drugs with therapeutic potential in PDAC. For
these preclinical disease models to be effective, they should both recapitulate
the molecular heterogeneity of PDAC and validate patient-specific therapeutic
sensitivities. To date however, deep characterization of the molecular
heterogeneity of PDAC PDX and PDO models and comparison with matched human
tumour remains largely unaddressed at the whole genome level. We conducted a
comprehensive assessment of the genetic landscape of 16 whole-genome pairs of
tumours and matched PDX, from primary PDAC and liver metastasis, including a
unique cohort of 5 'trios' of matched primary tumour, PDX, and PDO. We developed
a pipeline to score concordance between PDAC models and their paired human
tumours for genomic events, including mutations, structural variations, and copy
number variations. Tumour-model comparisons of mutations displayed single-gene
concordance across major PDAC driver genes, but relatively poor agreement across
the greater mutational load. Genome-wide and chromosome-centric analysis of
structural variation (SV) events highlights previously unrecognized concordance
across chromosomes that demonstrate clustered SV events. We found that
polyploidy presented a major challenge when assessing copy number changes;
however, ploidy-corrected copy number states suggest good agreement between
donor-model pairs. Collectively, our investigations highlight that while PDXs
and PDOs may serve as tractable and transplantable systems for probing the
molecular properties of PDAC, these models may best serve selective analyses
across different levels of genomic complexity. |
What is Fuchs' Uveitis? | Fuchs' Uveitis (FU) is a chronic, low-grade-inflammatory disorder, involving anterior uvea and vitreous. Fuchs uveitis (FU) is a frequent, chronic course of intraocular inflammation, which is associated with a gradual onset of decreased visual acuity. | Fuchs uveitis syndrome (FUS) is typically a unilateral, chronic, low-grade
inflammation of the anterior segment which manifests in young adulthood. It is
underdiagnosed because of its variable clinical spectrum. Although it can mimic
various forms of anterior uveitis, it is important to make the correct
diagnosis, based on clinical grounds, because both the management and prognosis
differ from those of other uveitides. While its etiology remains unknown, it is
possible that the disease has multiple causes that lead through different
pathogenic mechanisms to the same clinical entity. Although many patients do not
require treatment, it is not a benign condition, as often perceived. The high
incidence of glaucoma makes it mandatory that all patients with FUS should be
screened at regular intervals, even if they are not being actively treated and
are relatively asymptomatic. Posner-Schlossman-Syndrome (PSS) is clinically characterized by acute,
recurrent, mild, unilateral uveitis anterior accompanied by elevated intraocular
pressure (IOP). Fuchs´ Uveitis (FU) is a chronic, low-grade-inflammatory
disorder, involving anterior uvea and vitreous. The clinical findings show
remarkable similarities as well as differences. In our study, we determine the
composition of immune mediators in aqueous humor of patients with PSS and FU and
evaluate if immune mediators play a crucial role in specific viral intraocular
inflammation and IOP rises. Aqueous humor samples from 81 uveitis patients (=
eyes) presenting with either PSS or FU were collected at one time point. Local
intraocular antibody synthesis to rubella virus was confirmed in 65 patients,
whereas 16 were tested positively for human cytomegalovirus. Thirteen patients
with PSS and 10 patients with FU were treated with glaucoma medications.
Additionally, 11 cataract patients acted as control group. Immune mediator
concentrations were measured by Bio-Plex Pro assay. We observed in both PSS
(IFN-γ: 174.9 pg/mL; TNF-α: 25.1 pg/mL) and FU (IFN-γ: 25.4 pg/mL; TNF-α: 27.2
pg/mL) groups a significantly increased level of T-helper 1 immune mediators
compared to controls (IFN-γ, TNF-α: 0 pg/mL) [median]. Notably, PSS patients
(IL-1RA: 73.4 pg/mL; IL-8: 199.4 pg/mL; IL-10: 33.4 pg/mL; IP-10: 126350 pg/mL)
showed a stronger and more active ocular inflammatory response, than FU patients
(IL-1RA: 4.3 pg/mL; IL-8: 72.4 pg/mL; IL-10: 1.6 pg/mL; IP-10: 57400 pg/mL).
Furthermore, a negative correlation between mediators and IOP was seen in the
PSS group, potentially caused by acetazolamide-treatment. Our findings show that
immune mediators play a crucial role in specific viral intraocular inflammation
and influence IOP levels. Remarkable similarities but also significant
differences of immune mediator concentrations are apparent in PSS compared to
FU. High concentrations of IL-1RA, IL-8, IL-10, and IP-10 correlate with active
inflammation in PSS, while FU may trigger chronic inflammation. Our data also
substantiated a very similar composition of cytokines in those patients from the
PSS group suffering from ocular hypertension and thus offers a potential
explanation model for a negative correlation between mediators and IOP. |
Is overexpression of LY6K associated with better prognosis for non-small cell lung cancer patients? | No, LY6K overexpression is associated with poor prognosis for patients with NSCLC. | Gene expression profile analyses of non-small cell lung carcinomas (NSCLC) and
esophageal squamous cell carcinomas (ESCC) revealed that lymphocyte antigen 6
complex locus K (LY6K) was specifically expressed in testis and transactivated
in a majority of NSCLCs and ESCCs. Immunohistochemical staining using 406 NSCLC
and 265 ESCC specimens confirmed that LY6K overexpression was associated with
poor prognosis for patients with NSCLC (P = 0.0003), as well as ESCC (P =
0.0278), and multivariate analysis confirmed its independent prognostic value
for NSCLC (P = 0.0035). We established an ELISA to measure serum LY6K and found
that the proportion of the serum LY6K-positive cases was 38 of 112 (33.9%) NSCLC
and 26 of 81 (32.1%) ESCC, whereas only 3 of 74 (4.1%) healthy volunteers were
falsely diagnosed. In most cases, there was no correlation between serum LY6K
and conventional tumor markers of carcinoembryonic antigen (CEA) and cytokeratin
19-fragment (CYFRA 21-1) values. A combined ELISA for both LY6K and CEA
classified 64.7% of lung adenocarcinoma patients as positive, and the use of
both LY6K and CYFRA 21-1 increased sensitivity in the detection of lung squamous
cell carcinomas and ESCCs up to 70.4% and 52.5%, respectively, whereas the false
positive rate was 6.8% to 9.5%. In addition, knocked down of LY6K expression
with small interfering RNAs resulted in growth suppression of the lung and
esophageal cancer cells. Our data imply that a cancer-testis antigen, LY6K,
should be useful as a new type of tumor biomarker and probably as a target for
the development of new molecular therapies for cancer treatment. |
Are the members of the KRAB-ZNF gene family promoting gene repression? | The stem cell zinc finger 1 (SZF1)/ZNF589 protein belongs to the large family of Kruppel-associated box domain-zinc finger (KRAB-ZNF) transcription factors, which are present only in higher vertebrates and epigenetically repress transcription by recruiting chromatin-modifying complexes to the promoter regions of their respective target genes Because KAP1 is recruited to the DNA via interaction with KRAB-ZNF proteins, we suggest that expression of KRAB-ZNF genes may be controlled via an auto-regulatory mechanism involving KAP1. | The stem cell zinc finger 1 (SZF1)/ZNF589 protein belongs to the large family of
Krüppel-associated box domain-zinc finger (KRAB-ZNF) transcription factors,
which are present only in higher vertebrates and epigenetically repress
transcription by recruiting chromatin-modifying complexes to the promoter
regions of their respective target genes. Although the distinct biological
functions of most KRAB-ZNF proteins remain unknown, recent publications indicate
their implication in fundamental processes, such as cell proliferation,
apoptosis, differentiation, development, and tumorigenesis. SZF1/ZNF589 was
first identified as a gene with SZF1-1 isoform specifically expressed in CD34(+)
hematopoietic cells, strongly suggesting a role in epigenetic control of gene
expression in hematopoietic stem/progenitor cells (HSPCs). However, the function
of SZF1/ZNF589 in hematopoiesis has not yet been elucidated. Our study reveals
SZF1/ZNF589 as a gene with a human-specific nucleotide DNA-change, conferring
potential species-specific functional properties. Through shRNA-mediated
loss-of-function experiments, we found that changes in expression of fundamental
apoptosis-controlling genes are induced on SZF1/ZNF589 knockdown, resulting in
inhibited growth of hematopoietic cell lines and decreased progenitor potential
of primary human bone marrow CD34(+) cells. Moreover, we found that the
SZF1/ZNF589 gene is differentially regulated during hypoxia in CD34(+) HSPCs in
a cytokine-dependent manner, implicating its possible involvement in the
maintece of the hypoxic physiologic status of hematopoietic stem cells. Our
results establish the role of SZF1/ZNF589 as a new functional regulator of the
hematopoietic system. A substantial fraction of phenotypic differences between closely related species
are likely caused by differences in gene regulation. While this has already been
postulated over 30 years ago, only few examples of evolutionary changes in gene
regulation have been verified. Here, we identified and investigated binding
sites of the transcription factor GA-binding protein alpha (GABPa) aiming to
discover cis-regulatory adaptations on the human lineage. By performing
chromatin immunoprecipitation-sequencing experiments in a human cell line, we
found 11,619 putative GABPa binding sites. Through sequence comparisons of the
human GABPa binding regions with orthologous sequences from 34 mammals, we
identified substitutions that have resulted in 224 putative human-specific GABPa
binding sites. To experimentally assess the transcriptional impact of those
substitutions, we selected four promoters for promoter-reporter gene assays
using human and African green monkey cells. We compared the activities of
wild-type promoters to mutated forms, where we have introduced one or more
substitutions to mimic the ancestral state devoid of the GABPa consensus binding
sequence. Similarly, we introduced the human-specific substitutions into
chimpanzee and macaque promoter backgrounds. Our results demonstrate that the
identified substitutions are functional, both in human and nonhuman promoters.
In addition, we performed GABPa knock-down experiments and found 1,215 genes as
strong candidates for primary targets. Further analyses of our data sets link
GABPa to cognitive disorders, diabetes, KRAB zinc finger (KRAB-ZNF), and
human-specific genes. Thus, we propose that differences in GABPa binding sites
played important roles in the evolution of human-specific phenotypes. The KRAB-ZNF (Krüppel-associated box domain zinc finger) gene family is composed
of a large number of highly homologous genes, gene isoforms, and pseudogenes.
The proteins encoded by these genes, whose expression is often tissue-specific,
act as epigenetic suppressors contributing to the addition of repressive
chromatin marks and DNA methylation. Due to its high complexity, the KRAB-ZNF
family has not been studied in sufficient detail, and the involvement of its
members in carcinogenesis remains mostly unexplored. In this study, we aimed to
provide a comprehensive description of cancer-associated KRAB-ZNFs using
publicly available The Cancer Genome Atlas pan-cancer datasets. We analyzed 6727
tumor and normal tissue samples from 16 cancer types. Here, we showed that a
small but distinctive cluster of 16 KRAB-ZNFs is commonly upregulated across
multiple cancer cohorts in comparison to normal samples. We confirmed these
observations in the independent panels of lung and breast cancer cell lines and
tissues. This upregulation was also observed for most of the KRAB-ZNF splicing
variants, whose expression is simultaneously upregulated in tumors compared to
normal tissues. Finally, by analyzing the clinicopathological data for breast
and lung cancers, we demonstrated that the expression of cancer-associated
KRAB-ZNFs correlates with patient survival, tumor histology, and molecular
subtyping. Altogether, our study allowed the identification and characterization
of KRAB-ZNF factors that may have an essential function in cancer biology and
thus potential to become novel oncologic biomarkers and treatment targets. |
What does the boxed warning of pimavanserin say? | Pimavanserin bears a boxed warning about the risk of death associated with antipsychotic use in elderly patients with dementia. | OBJECTIVE: To summarize the US Food and Drug Administration's (FDA's) review of
the safety and effectiveness for pimavanserin, an atypical antipsychotic, for
the treatment of hallucinations and delusions associated with Parkinson's
disease psychosis. We describe the regulatory and clinical issues important to
the FDA's approval of this New Drug Application, with special focus on the
risk-benefit balance. We also describe a new labeling feature that presents
additional efficacy data to clinicians.
DATA SOURCES: Data sets for all relevant clinical trials of pimavanserin and the
Applicant's and FDA's analyses of these data were considered in this review.
Data were available from 616 patients with Parkinson's disease with
hallucinations and delusions who received at least 1 dose of pimavanserin, with
a total exposure of 825 patient-years in the Parkinson's disease psychosis
population.
RESULTS: Pimavanserin 34 mg/d was effective in treating hallucinations and
delusions associated with Parkinson's disease. In the Applicant's single pivotal
trial, 80.5% of pimavanserin patients experienced at least some improvement in
symptoms compared to 58.1% of patients taking placebo. Pimavanserin did not
worsen motor function, an adverse effect commonly observed with other
antipsychotics, probably because of a lack of consequential dopamine binding.
CONCLUSIONS: Pimavanserin is the only FDA-approved treatment for the
hallucinations and delusions seen in patients with psychosis of Parkinson's
disease. Although pimavanserin appears to have a pharmacologic mechanism that is
different from other atypical antipsychotics, concern remained that the
increased risk of death seen with antipsychotic use in elderly demented
patients, and described in all approved antipsychotic labels, would also occur
with pimavanserin. Pimavanserin bears the same boxed warning about the risk of
death associated with antipsychotic use in elderly patients with dementia. |
List Cdk targets that are dephosphorylated during cytokinesis | Aip1, Ede1 and Inn1 are Cdk targets that are dephosphorylated during cytokinesis. | The final event of the eukaryotic cell cycle is cytokinesis, when two new
daughter cells are born. How the timing and execution of cytokinesis is
controlled is poorly understood. Here, we show that downregulation of
cyclin-dependent kinase (Cdk) activity, together with upregulation of its
counteracting phosphatase Cdc14, controls each of the sequential steps of
cytokinesis, including furrow ingression, membrane resolution and cell
separation in budding yeast. We use phosphoproteome analysis of mitotic exit to
identify Cdk targets that are dephosphorylated at the time of cytokinesis. We
then apply a new and widely applicable tool to generate conditionally
phosphorylated proteins to identify those whose dephosphorylation is required
for cytokinesis. This approach identifies Aip1, Ede1 and Inn1 as cytokinetic
regulators. Our results suggest that cytokinesis is coordinately controlled by
the master cell cycle regulator Cdk together with its counteracting phosphatase
and that it is executed by concerted dephosphorylation of Cdk targets involved
in several cell biological processes. |
What is dystopia canthorum? | Dystopia canthorum is defined as a prominent broad nasal root with increased intercanthal distance. | Waardenburg's syndrome consists of lateral displacement of the inner canthi of
the eyes (dystopia canthorum), a broad nasal root and confluent eyebrows,
heterochromia iridum, a white forelock and congenital deafness. The syndrome is
inherited as a domit, but affected individuals do not necessarily have all of
the characteristics cited.Five hundred and fourteen pupils at a school for the
deaf were screened for features of this syndrome. Three cases were discovered.
Eleven other deaf children were found to have heterochromia iridum and two more
had white forelocks. The interocular dimensions of the remaining children were
recorded as standards by which to judge the presence of dystopia canthorum. The
results of chromosomal analysis in two cases with Waardenburg's syndrome were
normal.The findings provide further evidence that Waardenburg's syndrome is a
distinct entity and call in question Mackenzie's concept of a comprehensive
"first arch syndrome". Waardenburg syndrome (WS) type I is a non-progressive auditory-pigmentary
disorder comprising congenital sensorineural hearing loss and pigmentary
disturbances of the iris, hair, and skin, along with dystopia canthorum (lateral
displacement of the inner canthi). Affected individuals may have higher risk of:
neural tube defects, cleft lip and palate, limb abnormalities, and Hirschsprung
disease. The diagnosis is clinical and should be considered if the individual
has two major or one major plus two minor criteria. PAX3 is the only known gene
associated to the syndrome. Nevertheless, its use is mostly for genetic
counseling. Regarding different diagnosis, we may list: other causes of
non-progressive auditory-pigmentary disorder comprising congenital sensorineural
hearing loss, other types of Waardenburg syndrome, piebaldism, albinism,
vitiligo and Teitz syndrome. This paper presents a case of an eleven year old
boy with deafness and ophthalmologic alterations, based on his files and exams.
It reinforced the importance of the ophthalmologist contributing for the
diagnosis of this rare systemic disease, as it includes some ophthalmologic
alterations. We remind that the early diagnosis allows adequate stimulation for
the hearing loss, as well as preventive measures in case of pregt women
affected by genetic counseling. Waardenburg syndrome (WS) is a genetic disorder of which there are four distinct
types. These four types are differentiated by the physical defects which they
produce. Presented here is the case of a 13-year-old boy with WS Type I who was
observed and physically assessed in Mali, West Africa in 1969. His physical
findings included a bright blue coloring to the irises of the eyes, profound
sensorineural deafness, mutism, dystopia canthorum (lateral displacement of the
inner canthi of the eyes), broad nasal root, bushy eyebrows, and scaphoid
deformities of the supraorbital portions of the frontal bone. Because family
members were not available for interviews or physical examinations, it was not
possible to determine if this patient was suffering from a congenital form of
the disorder or from a spontaneous mutation. Given the patient's then location
in a remote rural area of Mali where electricity was absent, it was not possible
to perform additional diagnostic tests. The patient described here is the first
with WS in Mali, West Africa to have been medically observed and evaluated and
later documented in the medical literature. A second case of the syndrome in
Mali was described in the medical literature in 2011 in an 18-month-old infant
who did not have sensorineural hearing loss, but who did have a bilateral cleft
lip. An historical overview of WS is presented along with details concerning the
characteristics of the four types of the disorder. |
Is the protein ABCG2 (ATP-Binding Cassette, subfamily G, member 2, transporter) excreting uric acid? | Yes,
ABCG2 plays a central role on extra-renal uric acid excretion | INTRODUCTION: Hyperuricemia (chronically elevated serum uric acid) is the main
pathology underlying the development of gout, the most common inflammatory
arthropathy. Management of these conditions therefore relies on controlling
serum uric acid levels. ATP-binding cassette transporter, sub-family G, member 2
(ABCG2/BCRP) is a well-studied urate transporter expressed on apical membranes
in several tissues, including the intestine, liver, and kidney. Here, we discuss
the potential of future gout therapies targeting ABCG2. Areas covered: ABCG2
regulates serum uric acid via physiologically important roles in both renal and
extra-renal urate excretion. ABCG2 dysfunction, which promotes onset of
hyperuricemia, often results in decreased urate excretion through the
extra-renal (principally intestinal), rather than the renal pathway. This review
covers recent attempts to establish the basis of ABCG2 function according to
genetic diathesis, its molecular structure, and the effects of medication.
Furthermore, the possibility of treating gout and hyperuricemia by upregulating
intestinal ABCG2 expression is examined. Expert opinion: ABCG2 holds great
promise as a therapeutic target for these conditions, particularly considering
its involvement in extra-renal urate excretion. Manipulation of ABCG2, including
controlling the level and location of its expression, has the potential to
prevent gout by promoting uric acid excretion as effectively as general
uricosuric drugs.
ABBREVIATIONS: ATP-binding cassette (ABC), transmembrane domain (TMD),
nucleotide binding domain (NBD), single nucleotide polymorphism (SNP), single
nucleotide polymorphisms (SNPs). |
What is Heterochromia Iridis? | Heterochromia Iridis is a condition where the affected person has differences in the color of the iris. | BACKGROUND: Heterochromia iridis, asymmetry of iris pigmentation, has been well
described with congenital Horner syndrome. Acquired heterochromia associated
with lesions in the ocular sympathetic pathways in adulthood, however, is rare.
METHODS: Two cases are reported in which sympathectomy in adults resulted in
ipsilateral Horner syndrome with heterochromia. In each case, pharmacologic
testing with cocaine and hydroxyamphetamine was performed.
RESULTS: In both cases, sympathectomy occurred at the level of the second order
neuron, but hydroxyamphetamine testing suggested at least partial third order
neuron involvement.
CONCLUSION: Acquired heterochromia can occur in adults. The partial response to
hydroxyamphetamine in the two cases presented may reflect trans-synaptic
degeneration of the postganglionic neuron. A reduction in trophic influences on
iris melanocytes may have contributed to the observed heterochromia. The purpose of this study is to report a new and promising method for changing
iris color in a sectorial heterochromia iridis patient. A 22-year-old man with a
complaint of innate color disparity between his eyes presented to our clinic to
seek medical advice. He underwent a comprehensive ophthalmic examination,
including visual acuity, biomicroscopy, fundoscopy, intraocular pressure
measurements, endothelial cell count, and evaluation of iridocorneal angle. The
causes of acquired heterochromia were excluded. After a detailed explanation of
the procedure and probable side effects, the patient underwent an application
with a laser device that produces a frequency-doubled 532 nm wavelength Nd:YAG
laser beam with a spot size of 400 μm (selective laser trabeculoplasty laser
device). The heterochromic areas (brown) were divided into zones and a gradual
treatment pattern was performed to avoid inflammation and flare. The patient
showed no side effects such as increased intraocular pressure, pain, corneal
edema, hypopyon formation, decrease in visual acuity, synechia, or iris defect.
After two complete sessions, the color difference disappeared and a solid eye
color was achieved. |
How is transcriptional elongation affected by nucleosome positioning? | In order to elongate their products, both DNA and RNA polymerases must be able to overcome the inhibition presented by chromatin. Nucleosome arrays inhibit both initiation and elongation of transcripts. | We have examined the effects of nucleosome cores on the initiation and
elongation of RNA transcripts by phage T7 RNA polymerase in vitro. A
transcription template, pT207-18, was constructed containing tandemly repeated
207 base-pair (bp) nucleosome positioning sequences from a sea urchin
(Lytechinus variegatus) 5 S RNA gene inserted between the T7 and SP6
transcription promoters of pGEM-3Z. Nucleosome cores were reconstituted onto
supercoiled, closed circular pT207-18 DNA and double label transcription
experiments were performed to determine the effects of nucleosome cores on the
initiation and elongation of transcripts by T7 RNA polymerase. Both transcript
initiation and elongation were inhibited, the extent of the inhibition being
directly proportional to the number of nucleosome cores reconstituted onto the
pT207-18 DNA templates. Time course transcription experiments indicated that
nucleosome cores caused a reduction in the equilibrium length of transcripts and
not mere retardation of elongation rates. Continuous regularly spaced linear
arrays of nucleosomes were obtained by digesting reconstituted nucleosomel
pT207-18 templates with DraI, for which a unique restriction site lies within
the nucleosome positioning region of the 207 bp 5 S rDNA repeat sequence. After
in vitro transcription with T7 RNA polymerase an RNA ladder with 207 nucleotide
spacing was obtained, indicating that transcription can occur through continuous
arrays of positioned nucleosome cores. It is demonstrated that nucleosome cores
partially inhibit the elongation of transcripts by T7 RNA polymerase, while
allowing passage of the transcribing polymerase through each nucleosome core at
an upper limit efficiency of 85%. Hence, complete transcripts are produced with
high efficiency from short nucleosomal templates, while the production of
full-length transcripts from long nucleosomal arrays is relatively inefficient.
The results indicate that nucleosome cores have significant inhibitory effects
in vitro not only on transcription initiation but on transcription elongation as
well, and that special mechanisms may exist to overcome these inhibitory effects
in vivo. We have used a linear DNA template (239 bp) containing a nucleosome positioning
sequence (NX1) downstream of the T7 RNA polymerase promoter to study the
mechanism of transcription elongation through a nucleosome. Under ionic strength
approaching physiological conditions we have observed that transcription causes
nucleosome dissociation and histone redistribution within the template. We have
examined the role of the different elements that, in principle, could induce
nucleosome dissociation during transcription. The high affinity of histones for
single-stranded DNA observed in titration experiments performed using the
purified (+) and (-) strands of the NX1 fragment suggests that nucleosome
dissociation is not due to the formation of segments of single-stranded DNA by
RNA polymerase in the elongation process. Furthermore, our results show that
although RNA can interact with core histones, the synthesized RNA is not bound
to the histones dissociated by transcription. Our results indicate that core
histones released during transcription can be bound to naked DNA and chromatin
(with or without histones H1-H5). From the dynamic properties of excess histones
bound to chromatin, we suggest a nucleosome transcription mechanism in which
displaced histones are transiently bound to chromatin and finally are
reassembled with DNA after the passage of the polymerase. We have examined whether dissociation of the histone octamer is required for
elongation of RNA transcripts through arrays of nucleosome cores in vitro.
Control or dimethyl suberimidate-crosslinked histone octamers were reconstituted
onto supercoiled, closed circular pT207-18 DNA, which contains tandemly repeated
207-base-pair (bp) 5S rDNA nucleosome positioning sequences inserted between the
T7 and SP6 transcription promoters of pGEM-3Z. Double label transcription
experiments showed that there was little or no effect of extensive crosslinking
of the histone octamers on transcription initiation and elongation by T7 RNA
polymerase in vitro. Continuous regularly spaced linear arrays of either
crosslinked or control nucleosome cores were obtained by digesting reconstituted
nucleosomal pT207-18 templates with Dra I, a site that is protected from
digestion by the presence of positioned nucleosome cores in the 207-pb sequence.
After in vitro transcription with T7 RNA polymerase, an RNA ladder with
207-nucleotide spacing was obtained from templates reconstituted both with
crosslinked and with control histone octamers, demonstrating clearly that
neither partial nor complete dissociation of the histone octamer is essential
for transcription elongation through arrays of nucleosome cores in vitro. In eukaryotic cells, transcription and replication each occur on DNA templates
that are incorporated into nucleosomes. Formation of chromatin generally limits
accessibility of specific DNA sequences and inhibits progression of polymerases
as they copy information from the DNA. The processes that select sites for
initiating either transcription or replication are therefore strongly influenced
by factors that modulate the properties of chromatin proteins. Further, in order
to elongate their products, both DNA and RNA polymerases must be able to
overcome the inhibition presented by chromatin (Lipford and Bell 2001; Workman
and Kingston 1998). One way to adjust the properties of chromatin proteins is to
covalently modify them by adding or removing chemical moieties. Both histone and
non-histone chromatin proteins are altered by acetylation, methylation, and
other changes, and the 'nucleosome modifying' complexes that perform these
reactions are important components of pathways of transcriptional regulation
(Cote 2002; Orphanides and Reinberg 2000; Roth et al. 2001; Strahl and Allis
2000; Workman and Kingston 1998). Another way to alter the effects of
nucleosomes is to change the position of the histone octamers relative to
specific DNA sequences (Orphanides and Reinberg 2000; Verrijzer 2002; Wang 2002;
Workman and Kingston 1998). Since the ability of a sequence to be bound by
specific proteins can vary significantly whether the sequence is in the linkers
between nucleosomes or at various positions within a nucleosome, 'nucleosome
remodeling' complexes that rearrange nucleosome positioning are also important
regulators of transcription. Since the DNA replication machinery has to
encounter many of the same challenges posed by chromatin, it seems likely that
modifying and remodeling complexes also act during duplication of the genome,
but most of the current information on these factors relates to regulation of
transcription. This chapter describes the factor known variously as FACT in
humans, where it promotes elongation of RNA polymerase II on nucleosomal
templates in vitro (Orphanides et al. 1998, 1999), DUF in frogs, where it is
needed for DNA replication in oocyte extracts (Okuhara et al. 1999), and CP or
SPN in yeast, where it is linked in vivo to both transcription and replication
(Brewster et al. 2001; Formosa et al. 2001). Like the nucleosome modifying and
remodeling complexes, it is broadly conserved among eukaryotes, affects a wide
range of processes that utilize chromatin, and directly alters the properties of
nucleosomes. However, it does not have nucleosome modifying or standard
ATP-dependent remodeling activity, and therefore represents a third class of
chromatin modulating factors. It is also presently unique in the extensive
connections it displays with both transcription and replication: FACT/DUF/CP/SPN
appears to modify nucleosomes in a way that is directly important for the
efficient functioning of both RNA polymerases and DNA polymerases. While less is
known about the mechanisms it uses to promote its functions than for other
factors that affect chromatin, it is clearly an essential part of the complex
mixture of activities that modulate access to DNA within chromatin. Physical and
genetic interactions suggest that FACT/DUF/CP/SPN affects multiple pathways
within replication and transcription as a member of several distinct complexes.
Some of the interactions are easy to assimilate into models for replication or
transcription, such as direct binding to DNA polymerase alpha (Wittmeyer and
Formosa 1997; Wittmeyer et al. 1999), association with nucleosome modifying
complexes (John et al. 2000), and interaction with factors that participate in
elongation of RNA Polymerase II (Gavin et al. 2002; Squazzo et al. 2002). Others
are more surprising such as an association with the 19S complex that regulates
the function of the 20S proteasome (Ferdous et al. 2001; Xu et al. 1995), and
the indication that FACT/DUF/CP/SPN can act as a specificity factor for casein
kinase II (Keller et al. 2001). This chapter reviews the varied approaches that
have each revealed different aspects of the function of FACT/DUF/CP/SPN, and
presents a picture of a factor that can both alter nucleosomes and orchestrate
the assembly or activity of a broad range of complexes that act upon chromatin. Although the genomic pattern of nucleosome positioning is broadly conserved,
quantitative aspects vary over evolutionary timescales. We identify the cis and
trans determits of nucleosome positioning using a functional evolutionary
approach involving S. cerevisiae strains containing large genomic regions from
other yeast species. In a foreign species, nucleosome depletion at promoters is
maintained over poly(dA:dT) tracts, whereas internucleosome spacing and all
other aspects of nucleosome positioning tested are not. Interestingly, the
locations of the +1 nucleosome and RNA start sites shift in concert. Strikingly,
in a foreign species, nucleosome-depleted regions occur fortuitously in coding
regions, and they often act as promoters that are associated with a positioned
nucleosome array linked to the length of the transcription unit. We suggest a
three-step model in which nucleosome remodelers, general transcription factors,
and the transcriptional elongation machinery are primarily involved in
generating the nucleosome positioning pattern in vivo. |
How many annotated conserved human lncRNAs come from ancestral protein-coding genes? | ~ 55 | BACKGROUND: Only a small portion of human long non-coding RNAs (lncRNAs) appear
to be conserved outside of mammals, but the events underlying the birth of new
lncRNAs in mammals remain largely unknown. One potential source is remts of
protein-coding genes that transitioned into lncRNAs.
RESULTS: We systematically compare lncRNA and protein-coding loci across
vertebrates, and estimate that up to 5% of conserved mammalian lncRNAs are
derived from lost protein-coding genes. These lncRNAs have specific
characteristics, such as broader expression domains, that set them apart from
other lncRNAs. Fourteen lncRNAs have sequence similarity with the loci of the
contemporary homologs of the lost protein-coding genes. We propose that
selection acting on enhancer sequences is mostly responsible for retention of
these regions. As an example of an RNA element from a protein-coding ancestor
that was retained in the lncRNA, we describe in detail a short translated ORF in
the JPX lncRNA that was derived from an upstream ORF in a protein-coding gene
and retains some of its functionality.
CONCLUSIONS: We estimate that ~ 55 annotated conserved human lncRNAs are derived
from parts of ancestral protein-coding genes, and loss of coding potential is
thus a non-negligible source of new lncRNAs. Some lncRNAs inherited regulatory
elements influencing transcription and translation from their protein-coding
ancestors and those elements can influence the expression breadth and
functionality of these lncRNAs. |
Is modified vaccinia Ankara effective for smallpox? | Yes, modified vaccinia Ankara is effective for smallpox. | Despite the declaration of smallpox eradication in 1980, the existence of
variola stockpiles and the threat of bioterrorism demand that immunity to
smallpox through vaccination be maintained. Although the currently available
vaccine was used for the most successful medical intervention ever accomplished,
it also is associated with side effects that are difficult to accept in a
vaccine for a disease that has not been present for >25 years. Herein, we review
alternative approaches to maintaining immunity to smallpox through vaccination
with attenuated poxviruses, and we suggest modified vaccinia Ankara (MVA) as a
leading candidate for an alternative smallpox vaccine. While modified vaccinia virus Ankara (MVA) is currently in clinical development
as a safe vaccine against smallpox and heterologous infectious diseases, its
immunogenicity is likely limited due to the inability of the virus to replicate
productively in mammalian hosts. In light of recent data demonstrating that
vaccinia viruses, including MVA, preferentially infect antigen-presenting cells
(APCs) that play crucial roles in generating antiviral immunity, we hypothesized
that expression of specific cytokines and chemokines that mediate APC
recruitment and activation from recombit MVA (rMVA) vectors would enhance the
immunogenicity of these vectors. To test this hypothesis, we generated rMVAs
that express murine granulocyte-macrophage colony-stimulating factor (mGM-CSF),
human CCL20/human macrophage inflammatory protein 3alpha (hCCL20/hMIP-3alpha),
or human fms-like tyrosine kinase 3 ligand (hFlt3-L), factors predicted to
increase levels of dendritic cells (DCs), to recruit DCs to sites of
immunization, or to promote maturation of DCs in vivo, respectively. These rMVAs
also coexpress the well-characterized, immunodomit lymphocytic
choriomeningitis virus nucleoprotein (NP) antigen that enabled sensitive and
quantitative assessment of antigen-specific CD8(+) T-cell responses following
immunization of BALB/c mice. Our results demonstrate that immunization of mice
with rMVAs expressing mGM-CSF or hCCL20, but not hFlt3-L, results in two- to
fourfold increases of cellular immune responses directed against vector-encoded
antigens and 6- to 17-fold enhancements of MVA-specific antibody titers,
compared to those responses elicited by nonadjuvanted rMVA. Of note, cytokine
augmentation of cellular immune responses occurs when rMVAs are given as primary
immunizations but not when they are used as booster immunizations, suggesting
that these APC-modulating proteins, when used as poxvirus-encoded adjuvants, are
more effective at stimulating naïve T-cell responses than in promoting recall of
preexisting memory T-cell responses. Our results demonstrate that a strategy to
express specific genetic adjuvants from rMVA vectors can be successfully applied
to enhance the immunogenicity of MVA-based vaccines. The fear of malevolent use of variola virus by terrorists has led to the
implementation of a health care worker vaccination program and to the
consideration of vaccination for the general public. However, due to concerns
about side effects of the classical smallpox vaccine, especially for
immunocompromised individuals, a safer vaccine is urgently needed. We
characterized the immunogenicity of modified vaccinia virus Ankara (MVA), one of
the more promising alternative smallpox vaccines, in a cohort of 10 chronically
HIV-1-infected individuals undergoing highly active antiretroviral therapy
(HAART). Nine subjects received smallpox vaccination as children while one
subject was never vaccinated against smallpox. All the subjects had CD4 counts
>400 cells/mm(3) and 8 out of 10 had undetectable viral loads. MVA was able to
elicit humoral and cellular immune responses in the majority of individuals.
Vaccinia-specific antibodies were mainly of the IgG class while T cells specific
to vaccinia were predomitly CD8(+). The immune responses were maintained over
1 year. Similar vaccinia specific humoral immune responses were observed when
our cohort of HIV-1-infected individuals was compared to smallpox-vaccinated
healthy subjects. The observed immune responses suggest that the highly
attenuated MVA could be used as a substitute vaccine against smallpox in
chronically HIV-1-infected individuals undergoing HAART. Modified vaccinia virus Ankara (MVA) is a highly attenuated vaccinia virus that
is under consideration as an alternative to the conventional smallpox vaccine
Dryvax. MVA was attenuated by extensive passage of vaccinia virus Ankara in
chicken embryo fibroblasts. Several immunomodulatory genes and genes that
influence host range are deleted or mutated, and replication is aborted in the
late stage of infection in most nonavian cells. The effect of these mutations on
immunogenicity is not well understood. Since the structural genes appear to be
intact in MVA, it is hypothesized that critical targets for antibody
neutralization have been retained. To test this, we probed microarrays of the
Western Reserve (WR) proteome with sera from humans and macaques after MVA and
Dryvax vaccination. As most protein sequences of MVA are 97 to 99% identical to
those of other vaccinia virus strains, extensive binding cross-reactivity is
expected, except for those deleted or truncated. Despite different hosts and
immunization regimens, the MVA and Dryvax antibody profiles were broadly
similar, with antibodies against membrane and core proteins being the best
conserved. The responses to nonstructural proteins were less well conserved,
although these are not expected to influence virus neutralization. The broadest
antibody response was obtained for hyperimmune rabbits with WR, which is
pathogenic in rabbits. These data indicate that, despite the mutations and
deletions in MVA, its overall immunogenicity is broadly comparable to that of
Dryvax, particularly at the level of antibodies to membrane proteins. The work
supports other information suggesting that MVA may be a useful alternative to
Dryvax. Bavarian Nordic is developing IMVAMUNE, which is based on a live attenuated
modified vaccinia Ankara virus, for the potential prevention of smallpox
infection, particularly in those patients contraindicated to traditional
smallpox vaccines, such as the immunocompromised and those with eczema or
dermatitis. In phase I and II clinical trials, IMVAMUNE was highly immunogenic
and safe with no unexpected side effects or serious adverse effects reported in
either healthy volunteers, those immunocompromised by HIV infection or in
volunteers with atopic dermatitis. Additional phase II trials were ongoing in
these groups at the time of publication and phase III trials were planned for
2009. Smallpox vaccines based on replicating vaccinia virus are known to elicit rare
yet serious adverse events, particularly in human populations with immune
deficiency, atopic dermatitis and at the extremes of age. A vaccine that induces
protective immune responses equivalent to first-generation smallpox vaccines
while reducing the risk for severe adverse events is critical for a national
stockpile of smallpox vaccines. Modified vaccinia Ankara (MVA) has been proposed
as an immediate solution for vaccination of high-risk individuals. Bavarian
Nordic's vaccine MVA-BN (IMVAMUNE) is a MVA strain that is replication
incompetent in mammalian cell lines. IMVAMUNE has been administered to more than
1900 human subjects to date, including high-risk populations (e.g., people
diagnosed with atopic dermatitis or infected with HIV) in which standard
replicating vaccines are contraindicated. We review the Phase I clinical trial
safety profile and immune responses and compare them with other smallpox
vaccines, including ACAM2000 and Dryvax. Diseases such as HIV/AIDS, tuberculosis, malaria and cancer are prime targets
for prophylactic or therapeutic vaccination, but have proven partially or wholly
resistant to traditional approaches to vaccine design. New vaccines based on
recombit viral vectors expressing a foreign antigen are under intense
development for these and other indications. One of the most advanced and most
promising vectors is the attenuated, non-replicating poxvirus MVA (modified
vaccinia virus Ankara), a safer derivative of the uniquely successful smallpox
vaccine. Despite the ability of recombit MVA to induce potent humoral and
cellular immune responses against transgenic antigen in humans, especially when
used as the latter element of a heterologous prime-boost regimen, doubts are
occasionally expressed about the ultimate feasibility of this approach. In this
review, five common misconceptions over recombit MVA are discussed, and
evidence is cited to show that recombit MVA is at least sufficiently
genetically stable, manufacturable, safe, and immunogenic (even in the face of
prior anti-vector immunity) to warrant reasonable hope over the feasibility of
large-scale deployment, should useful levels of protection against target
pathogens, or therapeutic benefit for cancer, be demonstrated in efficacy
trials. The smallpox vaccine Vaccinia was successfully used to eradicate smallpox, but
although very effective, it was a very reactogenic vaccine and responsible for
the deaths of one or two people per million vaccinated. Modified Vaccinia virus
Ankara (MVA) is a replication-deficient and attenuated derivative, also used in
the smallpox eradication campaign and now being developed as a recombit viral
vector to produce vaccines against infectious diseases and cancer. Many clinical
trials of these new vaccines have been conducted, and the findings of these
trials are reviewed here. The safety of MVA is now well documented,
immunogenicity is influenced by the dose and vaccination regimen, and
information on the efficacy of MVA-vectored vaccines is now beginning to
accumulate. BACKGROUND: Conventional smallpox vaccines based on replicating vaccinia virus
(VV) strains (e.g. Lister Elstree, NYCBOH) are associated with a high incidence
of myo-/pericarditis, a severe inflammatory cardiac complication. A new smallpox
vaccine candidate based on a non-replicating Modified Vaccinia Ankara (MVA)
poxvirus has been assessed for cardiac safety in a large placebo-controlled
clinical trial.
METHODS: Cardiac safety of one and two doses of MVA compared to placebo was
assessed in 745 healthy subjects. Vaccinia-naïve subjects received either one
dose of MVA and one dose of placebo, two doses of MVA, or two doses of placebo
by subcutaneous injection four weeks apart; vaccinia-experienced subjects
received a single dose of MVA. Solicited and unsolicited adverse events (AE) and
cardiac safety parameters (recorded as Adverse Events of Special Interest, AESI)
were monitored after each injection.
RESULTS: A total of 5 possibly related AESI (3 cases of palpitations, 2 of
tachycardia) were reported during the study. No case of myo- or pericarditis
occurred. One possibly related serious AE (SAE) was reported during the 6-month
follow-up period (sarcoidosis). The most frequently observed AEs were injection
site reactions.
CONCLUSIONS: Vaccination with MVA was safe and well tolerated and did not
increase the risk for development of myo-/pericarditis.
TRIAL REGISTRATION: ClinicalTrials.gov NCT00316524. BACKGROUND: Modified vaccinia Ankara (MVA) is being developed as a safer
smallpox vaccine and is being placed in the US Strategic National Stockpile
(SNS) as a liquid formulation for subcutaneous (SC) administration at a dose of
1×10(8) TCID50 in a volume of 0.5mL. This study compared the safety and
immunogenicity of the standard formulation, dose and route with both a more
stable, lyophilized formulation and with an antigen-sparing intradermal (ID)
route of administration.
METHODS: 524 subjects were randomized to receive either a full dose of
Lyophilized-SC, a full dose of Liquid-SC or 20% (2×10(7) TCID50 in 0.1mL) of a
full dose Liquid-ID MVA on Days 0 and 28. Safety and immunogenicity were
followed through 180 days post second vaccination.
RESULTS: Among the 3 groups, the proportion of subjects with moderate/severe
functional local reactions was significantly different (P=0.0013) between the
Lyophilized-SC group (30.3%), the Liquid-SC group (13.8%) and Liquid-ID group
(22.0%) only after first vaccination; and for moderate/severe measured erythema
and/or induration after any vaccination (P=0.0001) between the Lyophilized-SC
group (58.2%), the Liquid-SC group (58.1%) and the Liquid-ID group (94.8%) and
the reactions lasted longer in the Liquid-ID group. In the ID Group, 36.1% of
subjects had mild injection site skin discoloration lasting ≥6 months. After
second vaccination Day (42-208), geometric mean of peak neutralization titers
were 87.8, 49.5 and 59.5 for the Lyophilized-SC, Liquid-SC and Liquid-ID groups,
respectively, and the maximum number of responders based on peak titer in each
group was 142/145 (97.9%), 142/149 (95.3%) and 138/146 (94.5%), respectively. At
180 days after the second vaccination, geometric mean neutralization titers
declined to 11.7, 10.2 and 10.4 with only 54.3%, 39.2% and 35.2% of subjects
remaining seropositive for the Lyophilized-SC, Liquid-SC and Liquid-ID groups,
respectively. Both the Lyophilized-SC and Liquid-ID groups were considered
non-inferior (primary objective) to the Liquid-SC group.
CONCLUSIONS: Transitioning to a lyophilized formulation, which has a longer
shelf life, will not negatively impact immunogenicity. In a situation where
insufficient vaccine is available, ID vaccination could be used, increasing the
number of available doses of vaccine in the SNS 5-fold (i.e., from 20 million to
100 million doses). Background. First- and second-generation smallpox vaccines are contraindicated
in individuals infected with human immunodeficiency virus (HIV). A new smallpox
vaccine is needed to protect this population in the context of biodefense
preparedness. The focus of this study was to compare the safety and
immunogenicity of a replication-deficient, highly attenuated smallpox vaccine
modified vaccinia Ankara (MVA) in HIV-infected and healthy subjects. Methods.
An open-label, controlled Phase II trial was conducted at 36 centers in the
United States and Puerto Rico for HIV-infected and healthy subjects. Subjects
received 2 doses of MVA administered 4 weeks apart. Safety was evaluated by
assessment of adverse events, focused physical exams, electrocardiogram
recordings, and safety laboratories. Immune responses were assessed using
enzyme-linked immunosorbent assay (ELISA) and a plaque reduction neutralization
test (PRNT). Results. Five hundred seventy-nine subjects were vaccinated at
least once and had data available for analysis. Rates of ELISA seropositivity
were comparably high in vaccinia-naive healthy and HIV-infected subjects,
whereas PRNT seropositivity rates were higher in healthy compared with
HIV-infected subjects. Modified vaccinia Ankara was safe and well tolerated with
no adverse impact on viral load or CD4 counts. There were no cases of
myo-/pericarditis reported. Conclusions. Modified vaccinia Ankara was safe and
immunogenic in subjects infected with HIV and represents a promising smallpox
vaccine candidate for use in immunocompromised populations. Erratum: Safety and Immunogenicity of Modified Vaccinia Ankara-Bavarian Nordic
Smallpox Vaccine in Vaccinia-Naive and Experienced Human Immunodeficiency
Virus-Infected Individuals: An Open-Label, Controlled Clinical Phase II Trial. Author information:
(1)Department of Pathology, Duke University Medical Center, Durham, North
Carolina, USA.
(2)Department of Medicine, Duke University Medical Center, Durham, North
Carolina, USA.
(3)Department of Pathology, Duke University Medical Center, Durham, North
Carolina, USA Department of Medicine, Duke University Medical Center, Durham,
North Carolina, USA.
(4)Department of Molecular Genetics and Microbiology, Duke University Medical
Center, Durham, North Carolina, USA.
(5)Department of Pathology, Duke University Medical Center, Durham, North
Carolina, USA Department of Medicine, Duke University Medical Center, Durham,
North Carolina, USA [email protected]. BACKGROUND: Modified Vaccinia Ankara MVA-BN® is a live, highly attenuated, viral
vaccine under advanced development as a non-replicating smallpox vaccine. In
this Phase II trial, the safety and immunogenicity of Modified Vaccinia Ankara
MVA-BN® (MVA) was assessed in a 56-80 years old population.
METHODS: MVA with a virus titer of 1 x 108 TCID50/dose was administered via
subcutaneous injection to 56-80 year old vaccinia-experienced subjects (N =
120). Subjects received either two injections of MVA (MM group) or one injection
of Placebo and one injection of MVA (PM group) four weeks apart. Safety was
evaluated by assessment of adverse events (AE), focused physical exams,
electrocardiogram recordings and safety laboratories. Solicited AEs consisted of
a set of pre-defined expected local reactions (erythema, swelling, pain,
pruritus, and induration) and systemic symptoms (body temperature, headache,
myalgia, nausea and fatigue) and were recorded on a memory aid for an 8-day
period following each injection. The immunogenicity of the vaccine was evaluated
in terms of humoral immune responses measured with a vaccinia-specific
enzyme-linked immunosorbent assay (ELISA) and a plaque reduction neutralization
test (PRNT) before and at different time points after vaccination.
RESULTS: Vaccinations were well tolerated by all subjects. No serious adverse
event related to MVA and no case of myopericarditis was reported. The overall
incidence of unsolicited AEs was similar in both groups. For both groups
immunogenicity responses two weeks after the final vaccination (i.e. Visit 4)
were as follows: Seroconversion (SC) rates (doubling of titers from baseline) in
vaccine specific antibody titers measured by ELISA were 83.3% in Group MM and
82.8% in Group PM (difference 0.6% with 95% exact CI [-13.8%, 15.0%]), and 90.0%
for Group MM and 77.6% for Group PM measured by PRNT (difference 12.4% with 95%
CI of [-1.1%, 27.0%]). Geometric mean titers (GMT) measured by ELISA two weeks
after the final vaccination for Group MM were 804.1 and 605.8 for Group PM (with
ratio of GMTs of 1.33 with 95% CI of [0.96, 1.84]). Similarly, GMTs measured by
PRNT were 210.3 for Group MM and 126.7 for Group PM (with ratio 1.66 and 95% CI
[0.95, 2.90]).
CONCLUSIONS: One or two doses of MVA were safe and immunogenic in a 56-80 years
old vaccinia-experienced population. No cases of myopericarditis were observed
following vaccinations with MVA. The safety, reactogenicity and immunogenicity
were similar to that seen in younger (18-55 year old) healthy populations as
investigated in other MVA trials. The results suggest that a single dose of MVA
in a 56-80 years old population was well tolerated and sufficient to rapidly
boost the long-term B cell memory response induced by a prior vaccination with a
traditional smallpox vaccine.
TRIAL REGISTRATION: ClinicalTrials.gov NCT00857493. INTRODUCTION: To guide the use of modified vaccinia Ankara (MVA) vaccine in
response to a release of smallpox virus, the immunogenicity and safety of
shorter vaccination intervals, and administration by jet injector (JI), were
compared to the standard schedule of administration on Days 1 and 29 by syringe
and needle (S&N).
METHODS: Healthy adults 18-40years of age were randomly assigned to receive MVA
vaccine subcutaneously by S&N on Days 1 and 29 (standard), Days 1 and 15, or
Days 1 and 22, or to receive the vaccine subcutaneously by JI on Days 1 and 29.
Blood was collected at four time points after the second vaccination for plaque
reduction neutralization test (PRNT) (primary endpoint) and ELISA (secondary
endpoint) antibody assays. For each subject, the peak PRNT (or ELISA) titer was
defined by the highest PRNT (or ELISA) titer among all available measurements
post second vaccination. Non-inferiority of a non-standard arm compared to the
standard arm was met if the upper limit of the 98.33% confidence interval of the
difference in the mean log2 peak titers between the standard and non-standard
arm was less than 1.
RESULTS: Non-inferiority of the PRNT antibody response was not established for
any of the three non-standard study arms. Non-inferiority of the ELISA antibody
response was established for the Day 1 and 22 compressed schedule and for
administration by JI. Solicited local reactions, such as redness and swelling,
tended to be more commonly reported with JI administration. Four
post-vaccination hypersensitivity reactions were observed.
CONCLUSIONS: Evaluations of the primary endpoint of PRNT antibody responses do
not support alternative strategies of administering MVA vaccine by S&N on
compressed schedules or administration by JI on the standard schedule.
TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT01827371. The smallpox vaccine based on the vaccinia virus was successfully used to
eradicate smallpox, but although very effective, it was a very reactogenic
vaccine and responsible for the deaths of one to two people per million
vaccinated. Modified Vaccinia virus Ankara (MVA) is an attenuated derivative,
also used in the smallpox eradication campaign and now being developed as a
recombit viral vector to produce vaccines against infectious diseases and
cancer. MVA can encode one or more foreign antigens and thus can function as a
multivalent vaccine. The vector can be used at biosafety level 1, has intrinsic
adjuvant properties, and induces humoral and cellular immune responses. Many
clinical trials of these new vaccines have been conducted, and the safety of MVA
is now well documented. Immunogenicity is influenced by the dose and vaccination
regimen, and information on the efficacy of MVA-vectored vaccines is now
beginning to accumulate. In this chapter, we provide protocols for generation,
isolation, amplification, and purification of recombit MVA for preclinical
and clinical evaluation. BACKGROUND: Modified Vaccinia Ankara (MVA) is a live, viral vaccine under
advanced development as a non-replicating smallpox vaccine. A randomised,
double-blind, placebo-controlled phase III clinical trial was conducted to
demonstrate the humoral immunogenic equivalence of three consecutively
manufactured MVA production lots, and to confirm the safety and tolerability of
MVA focusing on cardiac readouts.
METHODS: The trial was conducted at 34 sites in the US. Vaccinia-naïve adults
aged 18-40 years were randomly allocated to one of four groups using a 1:1:1:1
randomization scheme. Subjects received either two MVA injections from three
consecutive lots (Groups 1-3), or two placebo injections (Group 4), four weeks
apart. Everyone except personnel involved in vaccine handling and administration
was blinded to treatment. Safety assessment focused on cardiac monitoring
throughout the trial. Vaccinia-specific antibody titers were measured using a
Plaque Reduction Neutralization Test (PRNT) and an Enzyme-Linked Immunosorbent
Assay (ELISA). The primary immunogenicity endpoint was Geometric Mean Titers
(GMTs) after two MVA vaccinations measured by PRNT at trial visit 4. This trial
is registered with ClinicalTrials.gov, number NCT01144637.
RESULTS: Between March 2013 and May 2014, 4005 subjects were enrolled and
received at least one injection of MVA (n = 3003) or placebo (n = 1002). The
three MVA lots induced equivalent antibody titers two weeks after the second
vaccination, with seroconversion rates of 99·8% (PRNT) and 99·7% (ELISA).
Overall, 180 (6·0%) subjects receiving MVA and 29 (2·9%) subjects in the placebo
group reported at least one unsolicited Adverse Event (AE) that was considered
trial-related. Vaccination was well tolerated without significant safety
concerns, particularly regarding cardiac assessment.
CONCLUSIONS: The neutralizing and total antibody titers induced by each of the
three lots were equivalent. No significant safety concerns emerged in this
healthy trial population, especially regarding cardiac safety, thus confirming
the excellent safety and tolerability profile of MVA.
TRIAL REGISTRATION: ClinicalTrials.gov NCT01144637. |
Does nintedanib hold promise for lung disease associated with systemic sclerosis? | Yes, nintedanib holds promise for lung disease associated with systemic sclerosis. It is being tested in a clinical trial. | INTRODUCTION: Novel compounds targeting various aspects of fibrogenesis have
been developed consequent to the increasing knowledge of the pathogenetic
mechanisms of the interstitial lung diseases (ILDs). The authors review the
evolution of treatment approaches in the ILDs, informed by recent
placebo-controlled trials, and discuss current clinical trials in which emerging
pathogenetic mechanisms are targeted as novel therapeutic agents.
AREAS COVERED: In idiopathic pulmonary fibrosis (IPF), recent randomised,
placebo-controlled trials have tested the efficacy of new therapies, and
although primary end points have not been met in most, treatment effects have
been observed. The demonstration of harmful effects from widely used IPF
therapies has been equally important. Pirfenidone and nintedanib are emerging
agents that exert pleiotropic effects, reflective of the multiple mechanistic
pathways of IPF. Treatment may necessitate a similarly multifaceted approach
using combination regimens of antifibrotic and antioxidant agents in order to be
effective. In other ILDs, including systemic sclerosis, other connective tissue
diseases and pulmonary sarcoidosis, the inflammatory/fibrotic model remains
appropriate. Studies in systemic sclerosis have provided 'proof of concept' data
for immunosuppressive therapy in the prevention of disease progression but there
is a continuing need for controlled clinical trials in the more prevalent ILDs.
EXPERT OPINION: In IPF, significant treatment effects have been reported with
pirfenidone, nintedanib and N-acetylcysteine. Combinations of these pleiotropic
agents, along with future monotherapies, in 'oncological regimens' may hold the
key to more effective IPF treatment. In disorders other than IPF, there is an
ongoing need for the controlled evaluation of traditional anti-inflammatory and
immunosuppressive therapies. 'Cohort enrichment' (the selective recruitment of
patients most likely to progress) holds the key to the identification of
worthwhile treatment benefits. Although interstitial lung disease accounts for the majority of deaths of
patients with systemic sclerosis, treatment options for this manifestation of
the disease are limited. Few high-quality, randomized, controlled trials exist
for systemic sclerosis-related interstitial lung disease, and historically,
studies have favored the use of cyclophosphamide. However, the benefit of
cyclophosphamide for this disease is tempered by its complex adverse event
profile. More recent studies have demonstrated the effectiveness of
mycophenolate for systemic sclerosis-related interstitial lung disease,
including Scleroderma Lung Study II. This review highlights the findings of this
study, which was the first randomized controlled trial to compare
cyclophosphamide with mycophenolate for the treatment of systemic
sclerosis-related interstitial lung disease. The results reported in this trial
suggest that there is no difference in treatment efficacy between mycophenolate
and cyclophosphamide; however, mycophenolate appears to be safer and more
tolerable than cyclophosphamide. In light of the ongoing advances in our
understanding of the pathogenic mechanisms underlying interstitial lung disease
in systemic sclerosis, this review also summarizes novel treatment approaches,
presenting clinical and preclinical evidence for rituximab, tocilizumab,
pirfenidone, and nintedanib, as well as hematopoietic stem cell transplantation
and lung transplantation. This review further explores how reaching a consensus
on appropriate study end points, as well as trial enrichment criteria, is
central to improving our ability to judiciously evaluate the safety and efficacy
of emerging experimental therapies for systemic sclerosis-related interstitial
lung disease. OBJECTIVES: Nintedanib is a tyrosine kinase inhibitor approved for the treatment
of idiopathic pulmonary fibrosis (IPF). The pathological pathways involved in
fibrogenesis in IPF and interstitial lung disease associated with systemic
sclerosis (SSc-ILD) show commonalities; both involve fibroblast activation,
myofibroblast accumulation and deposition of extracellular matrix. The SENSCIS™
trial is a randomised, placebo-controlled Phase III trial that will evaluate the
efficacy and safety of nintedanib in patients with SSc-ILD (NCT02597933).
METHODS: Approximately 520 patients with SSc (based on 2013 American College of
Rheumatology/European League Against Rheumatism criteria) and ILD (≥10% fibrosis
of the lungs, confirmed by central assessment of chest high resolution computed
tomography), forced vital capacity (FVC) ≥40% predicted and diffusing capacity
for carbon monoxide of 30-89% predicted will be enrolled. Patients will be
randomised (1:1) to nintedanib 150 mg twice daily or placebo, stratified by the
presence of anti-topoisomerase I antibody. To reflect real-world management,
patients receiving prednisone (≤10 mg/day) and/or a stable dose of mycophenolate
or methotrexate, will be eligible. The primary endpoint is the annual rate of
decline in FVC (mL/ year) assessed over 52 weeks. Patients will remain on
blinded study treatment until the last patient completes 52 weeks of treatment
or for a maximum of 100 weeks of treatment. Key secondary endpoints are absolute
changes from baseline in modified Rod skin score and St George's Respiratory
Questionnaire at week 52.
RESULTS: Recruitment for the trial began in November 2015.
CONCLUSIONS: This trial will assess the efficacy and safety of nintedanib in
patients with SSc-ILD. Systemic sclerosis is a connective tissue disease characterized by progressive
skin thickening and a wide spectrum of internal organ involvement. Pathogenesis
includes vasculopathy, inflammation, and fibrosis. Although immunosuppressants
such as cyclophosphamide and mycophenolate mofetil have shown some benefit in
interstitial lung disease management, it is still a major cause of
morbi-mortality in these patients. Therefore, there is a current need for new
therapies. Here, we report a 65-year-old female patient with limited cutaneous
systemic sclerosis, anti-topoisomerase-positive and extensive lung disease. The
patient developed progressive lung fibrosis under several immunosuppressants and
was started on nintedanib, with clinical and functional stabilization.
Nintedanib is a tyrosine-kinase inhibitor that blocks several profibrotic
pathways, inhibiting proliferation and migration of fibroblasts and decreasing
the synthesis of extracellular matrix proteins. It is approved for idiopathic
lung fibrosis and has demonstrated good results in inhibiting migration and
proliferation of systemic sclerosis dermal fibroblasts, constituting a promising
agent for systemic sclerosis-associated lung fibrosis. BACKGROUND: Interstitial lung disease (ILD) is a common manifestation of
systemic sclerosis and a leading cause of systemic sclerosis-related death.
Nintedanib, a tyrosine kinase inhibitor, has been shown to have antifibrotic and
antiinflammatory effects in preclinical models of systemic sclerosis and ILD.
METHODS: We conducted a randomized, double-blind, placebo-controlled trial to
investigate the efficacy and safety of nintedanib in patients with ILD
associated with systemic sclerosis. Patients who had systemic sclerosis with an
onset of the first non-Raynaud's symptom within the past 7 years and a
high-resolution computed tomographic scan that showed fibrosis affecting at
least 10% of the lungs were randomly assigned, in a 1:1 ratio, to receive 150 mg
of nintedanib, administered orally twice daily, or placebo. The primary end
point was the annual rate of decline in forced vital capacity (FVC), assessed
over a 52-week period. Key secondary end points were absolute changes from
baseline in the modified Rod skin score and in the total score on the St.
George's Respiratory Questionnaire (SGRQ) at week 52.
RESULTS: A total of 576 patients received at least one dose of nintedanib or
placebo; 51.9% had diffuse cutaneous systemic sclerosis, and 48.4% were
receiving mycophenolate at baseline. In the primary end-point analysis, the
adjusted annual rate of change in FVC was -52.4 ml per year in the nintedanib
group and -93.3 ml per year in the placebo group (difference, 41.0 ml per year;
95% confidence interval [CI], 2.9 to 79.0; P = 0.04). Sensitivity analyses based
on multiple imputation for missing data yielded P values for the primary end
point ranging from 0.06 to 0.10. The change from baseline in the modified Rod
skin score and the total score on the SGRQ at week 52 did not differ
significantly between the trial groups, with differences of -0.21 (95% CI, -0.94
to 0.53; P = 0.58) and 1.69 (95% CI, -0.73 to 4.12 [not adjusted for multiple
comparisons]), respectively. Diarrhea, the most common adverse event, was
reported in 75.7% of the patients in the nintedanib group and in 31.6% of those
in the placebo group.
CONCLUSIONS: Among patients with ILD associated with systemic sclerosis, the
annual rate of decline in FVC was lower with nintedanib than with placebo; no
clinical benefit of nintedanib was observed for other manifestations of systemic
sclerosis. The adverse-event profile of nintedanib observed in this trial was
similar to that observed in patients with idiopathic pulmonary fibrosis;
gastrointestinal adverse events, including diarrhea, were more common with
nintedanib than with placebo. (Funded by Boehringer Ingelheim; SENSCIS
ClinicalTrials.gov number, NCT02597933.). A proportion of patients with fibrosing interstitial lung diseases (ILDs)
develop a progressive phenotype characterised by decline in lung function,
worsening quality of life and early mortality. Other than idiopathic pulmonary
fibrosis (IPF), there are no approved drugs for fibrosing ILDs and a poor
evidence base to support current treatments. Fibrosing ILDs with a progressive
phenotype show commonalities in clinical behaviour and in the pathogenic
mechanisms that drive disease worsening. Nintedanib is an intracellular
inhibitor of tyrosine kinases that has been approved for treatment of IPF and
has recently been shown to reduce the rate of lung function decline in patients
with ILD associated with systemic sclerosis (SSc-ILD). In vitro data demonstrate
that nintedanib inhibits several steps in the initiation and progression of lung
fibrosis, including the release of pro-inflammatory and pro-fibrotic mediators,
migration and differentiation of fibrocytes and fibroblasts, and deposition of
extracellular matrix. Nintedanib also inhibits the proliferation of vascular
cells. Studies in animal models with features of fibrosing ILDs such as IPF,
SSc-ILD, rheumatoid arthritis-ILD, hypersensitivity pneumonitis and silicosis
demonstrate that nintedanib has anti-fibrotic activity irrespective of the
trigger for the lung pathology. This suggests that nintedanib inhibits
fundamental processes in the pathogenesis of fibrosis. A trial of nintedanib in
patients with progressive fibrosing ILDs other than IPF (INBUILD) will report
results in 2019. Nintedanib (Ofev™), an oral triple kinase inhibitor targeting pro-fibrotic
pathways, has been used for treatment of idiopathic pulmonary fibrosis (IPF).
Based on positive results from phase III, placebo-controlled, randomized
comparative clinical trial conducted in patients with systemic
sclerosis-associated interstitial lung disease (SSc-ILD), nintedanib received
marketing approval in the United States and Japan for the treatment of SSc-ILD.
Nintedanib significantly reduced the annual rate of decline in forced vital
capacity over 52 weeks compared with placebo. The safety profiles observed in
this trial were consistent with those reported in IPF patients, and the most
common adverse events were gastrointestinal disorders, including diarrhea,
nausea, and vomiting, which sometimes lead to discontinuation or permanent dose
reduction of nintedanib. In contrast, serious adverse events were infrequent and
were related mostly to worsening of cardiopulmonary involvement of SSc. This
review summarizes the milestones in development of nintedanib leading to the
approval for the treatment of SSc-ILD, and covers mechanisms of action, efficacy
results and safety profiles, and future perspectives of nintedanib. |
What is the LINCS Program? | The Library of Integrated Network-based Cellular Signatures (LINCS) is an NIH Common Fund program that catalogs how human cells globally respond to chemical, genetic, and disease perturbations. | The National Institutes of Health Library of Integrated Network-based Cellular
Signatures (LINCS) program is generating extensive multidimensional data sets,
including biochemical, genome-wide transcriptional, and phenotypic cellular
response signatures to a variety of small-molecule and genetic perturbations
with the goal of creating a sustainable, widely applicable, and readily
accessible systems biology knowledge resource. Integration and analysis of
diverse LINCS data sets depend on the availability of sufficient metadata to
describe the assays and screening results and on their syntactic, structural,
and semantic consistency. Here we report metadata specifications for the most
important molecular and cellular components and recommend them for adoption
beyond the LINCS project. We focus on the minimum required information to model
LINCS assays and results based on a number of use cases, and we recommend
controlled terminologies and ontologies to annotate assays with syntactic
consistency and semantic integrity. We also report specifications for a simple
annotation format (SAF) to describe assays and screening results based on our
metadata specifications with explicit controlled vocabularies. SAF specifically
serves to programmatically access and exchange LINCS data as a prerequisite for
a distributed information management infrastructure. We applied the metadata
specifications to annotate large numbers of LINCS cell lines, proteins, and
small molecules. The resources generated and presented here are freely
available. The NIH-funded LINCS program has been initiated to generate a library of
integrated, network-based, cellular signatures (LINCS). A novel high-throughput
gene-expression profiling assay known as L1000 was the main technology used to
generate more than a million transcriptional profiles. The profiles are based on
the treatment of 14 cell lines with one of many perturbation agents of interest
at a single concentration for 6 and 24 hours duration. In this study, we focus
on the chemical compound treatments within the LINCS data set. The experimental
variables available include number of replicates, cell lines, and time points.
Our study reveals that compound characterization based on three cell lines at
two time points results in more genes being affected than six cell lines at a
single time point. Based on the available LINCS data, we conclude that the most
optimal experimental design to characterize a large set of compounds is to test
them in duplicate in three different cell lines. Our conclusions are constrained
by the fact that the compounds were profiled at a single, relative high
concentration, and the longer time point is likely to result in phenotypic
rather than mechanistic effects being recorded. BACKGROUND: One of the most successful approaches to develop new small molecule
therapeutics has been to start from a validated druggable protein target.
However, only a small subset of potentially druggable targets has attracted
significant research and development resources. The Illuminating the Druggable
Genome (IDG) project develops resources to catalyze the development of likely
targetable, yet currently understudied prospective drug targets. A central
component of the IDG program is a comprehensive knowledge resource of the
druggable genome.
RESULTS: As part of that effort, we have developed a framework to integrate,
navigate, and analyze drug discovery data based on formalized and standardized
classifications and annotations of druggable protein targets, the Drug Target
Ontology (DTO). DTO was constructed by extensive curation and consolidation of
various resources. DTO classifies the four major drug target protein families,
GPCRs, kinases, ion channels and nuclear receptors, based on phylogenecity,
function, target development level, disease association, tissue expression,
chemical ligand and substrate characteristics, and target-family specific
characteristics. The formal ontology was built using a new software tool to
auto-generate most axioms from a database while supporting manual knowledge
acquisition. A modular, hierarchical implementation facilitate ontology
development and maintece and makes use of various external ontologies, thus
integrating the DTO into the ecosystem of biomedical ontologies. As a formal
OWL-DL ontology, DTO contains asserted and inferred axioms. Modeling data from
the Library of Integrated Network-based Cellular Signatures (LINCS) program
illustrates the potential of DTO for contextual data integration and nuanced
definition of important drug target characteristics. DTO has been implemented in
the IDG user interface Portal, Pharos and the TIN-X explorer of protein target
disease relationships.
CONCLUSIONS: DTO was built based on the need for a formal semantic model for
druggable targets including various related information such as protein, gene,
protein domain, protein structure, binding site, small molecule drug, mechanism
of action, protein tissue localization, disease association, and many other
types of information. DTO will further facilitate the otherwise challenging
integration and formal linking to biological assays, phenotypes, disease models,
drug poly-pharmacology, binding kinetics and many other processes, functions and
qualities that are at the core of drug discovery. The first version of DTO is
publically available via the website http://drugtargetontology.org/ , Github (
http://github.com/DrugTargetOntology/DTO ), and the NCBO Bioportal (
http://bioportal.bioontology.org/ontologies/DTO ). The long-term goal of DTO is
to provide such an integrative framework and to populate the ontology with this
information as a community resource. The Library of Integrated Network-based Cellular Signatures (LINCS) program is a
national consortium funded by the NIH to generate a diverse and extensive
reference library of cell-based perturbation-response signatures, along with
novel data analytics tools to improve our understanding of human diseases at the
systems level. In contrast to other large-scale data generation efforts, LINCS
Data and Signature Generation Centers (DSGCs) employ a wide range of assay
technologies cataloging diverse cellular responses. Integration of, and unified
access to LINCS data has therefore been particularly challenging. The Big Data
to Knowledge (BD2K) LINCS Data Coordination and Integration Center (DCIC) has
developed data standards specifications, data processing pipelines, and a suite
of end-user software tools to integrate and annotate LINCS-generated data, to
make LINCS signatures searchable and usable for different types of users. Here,
we describe the LINCS Data Portal (LDP) (http://lincsportal.ccs.miami.edu/), a
unified web interface to access datasets generated by the LINCS DSGCs, and its
underlying database, LINCS Data Registry (LDR). LINCS data served on the LDP
contains extensive metadata and curated annotations. We highlight the features
of the LDP user interface that is designed to enable search, browsing,
exploration, download and analysis of LINCS data and related curated content. Gene expression profiling using transcriptional drug perturbations are useful
for many biomedical discovery studies including drug repurposing and elucidation
of drug mechanisms (MoA) and many other pharmacogenomic applications. However,
limited data availability across cell types has severely hindered our capacity
to progress in these areas. To fill this gap, recently, the LINCS program
generated almost 1.3 million profiles for over 40,000 drug and genetic
perturbations for over 70 different human cell types, including meta information
about the experimental conditions and cell lines. Unfortunately, Big Data like
the ones generated from the ongoing LINCS program do not enable easy insights
from the data but possess considerable challenges toward their analysis. In this
paper, we address some of these challenges. Specifically, first, we study the
gene expression signature profiles from all cell lines and their perturbagents
in order to obtain insights in the distributional characteristics of available
conditions. Second, we investigate the differential expression of genes for all
cell lines obtaining an understanding of condition dependent differential
expression manifesting the biological complexity of perturbagents. As a result,
our analysis helps the experimental design of follow-up studies, e.g., by
selecting appropriate cell lines. |
Is PF-05190457 an inverse agonist of the ghrelin receptor? | Yes, PF-05190457 is an inverse agonist of the ghrelin receptor. | |
Is Ubrogepant effective for migraine? | Yes, Ubrogepant is effective for treatment of migraine. | AIM: The aim of this trial was to evaluate the efficacy and tolerability of
ubrogepant (MK-1602), a calcitonin gene-related peptide receptor antagonist
(CGRP-RA), for the acute treatment of migraine.
METHODS: This double-blind, placebo-controlled study randomized 834 participants
to treat one migraine attack with ubrogepant 1 mg, 10 mg, 25 mg, 50 mg, 100 mg,
or placebo in a 1:1 ratio. The co-primary endpoints were pain freedom and
headache response at two hours. The first primary hypothesis tested the
dose-response trend for two-hour pain freedom using a logistic regression model.
Subsequent hypotheses tested the effects of each dose on the co-primary
endpoints, using a closed sequential testing procedure to control for
multiplicity.
RESULTS: A total of 527 participants received ubrogepant and 113 received
placebo. A positive response trend in the proportion of participants achieving
two-hour pain freedom was demonstrated (p < 0.001). Ubrogepant 100 mg was
significantly superior to placebo for two-hour pain freedom (25.5% vs 8.9%) but
not for two-hour headache response. Per the prespecified multiplicity strategy,
this nonsignificant result precluded further formal hypothesis testing, although
the 50 mg and 25 mg doses demonstrated nominal significance over placebo for
two-hour pain freedom (unadjusted p < 0.05). Overall, adverse events were
similar between ubrogepant and placebo.
CONCLUSION: This trial supports ubrogepant's efficacy and provides further
evidence that CGRP-RAs are viable options for the acute treatment of migraine. Calcitonin gene-related peptide (CGRP) is a signaling neuropeptide released from
activated trigeminal sensory afferents in headache and facial pain disorders.
There are a handful of CGRP-targeted therapies currently in phase 3 studies for
migraine acute treatment or prevention. Currently, 4 monoclonal antibodies
targeting either the CGRP ligand or receptor are being studied for migraine
prevention: ALD403 (eptinezumab), AMG 334 (erenumab), LY2951742 (galcanezumab),
and TEV-48125 (fremanezumab). Meanwhile, 1 small-molecule CGRP receptor
antagonist (ubrogepant, MK-1602) is currently in phase 3 studies for the acute
treatment of migraine. Two of these anti-CGRP monoclonal antibodies are in
clinical trials for cluster headache prevention as well. Several other
small-molecular CGRP receptor antagonists are in earlier stages of development
for acute migraine treatment or prevention. In this review, we will discuss the
growing body of clinical trials studying CGRP-targeted therapies for migraine
and cluster headache. Conflict of interest statement: Interessenkonflikt: Prof. Dr. Hans-Christoph
Diener hat Honorare für die Planung, Ausführung oder Teilnahme an klinischen
Studien, Teilnahme an Advisory Boards oder Vorträge erhalten von: Addex Pharma,
Alder, Allergan, Almirall, Amgen, AstraZeneca, Autonomic Technology, Bayer
Vital, Berlin Chemie, Böhringer Ingelheim, Bristol-Myers Squibb, Chordate,
CoLucid, Coherex, Electrocore, GlaxoSmithKline, Grünenthal, Janssen-Cilag,
Labrys Biologicals, Lilly, La Roche, 3M Medica , Menerini, Minster, MSD,
Novartis, Johnson & Johnson, Pierre Fabre, Pfizer, Schaper und Brümmer, Sanofi,
St. Jude Medical, TEVA und Weber & Weber. Fizielle Unterstützung für
Forschungsprojekte wurde gewährt von: Allergan, Almirall, AstraZeneca, Bayer,
Electrocore, GSK, Janssen-Cilag, MSD und Pfizer. Kopfschmerzforschung an der
Universitätsklinik für Neurologie und dem Westdeutschen Kopfschmerzzentrum Essen
erfolgt durch: Deutsche Forschungsgemeinschaft (DFG), Bundesministerium für
Bildung und Forschung (BMBF) und die Europäische Union (EU). Prof.
Hans-Christoph Diener besitzt keine Aktien oder Anteile von
Pharmafirmen.Priv.-Doz. Dr. Charly Gaul hat Honorare für Vorträge oder Teilnahme
an Advisory Boards erhalten von: Allergan Pharma, Ratiopharm, Boehringer
Ingelheim Pharma, Lilly, Novartis Pharma, Desitin Arzneimittel, Cerbotec, Bayer
vital, Hormosan Pharma, electroCore, Reckitt Benckiser und Grünenthal erhalten.
C. G. besitzt keine Aktien oder Anteile von Pharmafirmen.Priv.-Doz. Dr. Dagny
Holle hat Honorare für Vorträge oder Forschungsprojekte erhalten von Allergan
Pharma, Lilly, Novartis Pharma, Desitin Arzneimittel, Hormosan Pharma,
electroCore, Grünenthal erhalten. D. H. besitzt keine Aktien oder Anteile von
Pharmafirmen.Lazaros Lazaridis gibt an dass kein Interessenkonflikt besteht.Dr.
Steffen Nägel hat einmalig ein Honorar von Allergan Pharma erhalten. Er besitzt
keine Aktien oder Anteile von Pharmafirmen.Priv.-Doz. Dr. Mark Obermann hat
fizielle Unterstützung für Forschungsprojekte und/oder Honorare von Biogen
Idec, Novartis, Sanofi-Aventis, Genzyme, Pfizer, Teva und Heel erhalten. Er hat
des Weiteren Forschungsstipendien von Allergan, Electrocore, Heel und dem
Bundesministerium für Bildung und Forschung (BMBF) erhalten. Merck & Co., Inc. (Kenilworth, New Jersey) has recently published an integrated
strategy for implementation of dried blood spots (DBS) in late-stage trials for
population pharmacokinetic (PK) modeling. We applied this strategy for another
late-stage clinical program: ubrogepant (MK-1602), a novel oral calcitonin
gene-related peptide receptor antagonist for acute treatment of migraine. At the
time of implementation, ubrogepant was entering phase 2 development. DBS was
implemented to acquire PK information proximal to an acute migraine event to
enable exposure-response modeling. The clinical endpoint was a spontaneous
event, which generally occurs outside a clinic visit. Thus, an innovative
feature of this trial was facilitating DBS in an outpatient setting. In vitro
and bioanalytical tests established initial method feasibility and suitability
for further evaluations in the clinic. A quantitative relationship was developed
between blood and plasma concentrations from concurrently collected samples in a
phase 1 (healthy subjects) and phase 2 (target patient population) study using
graphical and population PK approaches. This integrated information was
presented to the Food and Drug Administration for regulatory input. Following
regulatory concurrence, DBS was poised for use in further clinical studies.
Population PK modeling was used to dissect sources of variability contributing
to DBS collection in the outpatient setting. What has been learned from this
program has informed the broader integrated strategy of Merck & Co., Inc.
(Kenilworth, NJ) for DBS implementation in clinical trials and research to
improve the precision of PK data collected in an outpatient setting. Migraine is a highly prevalent, severe, and disabling neurological condition
with a significant unmet need for effective acute therapies. Patients (~50%) are
dissatisfied with their currently available therapies. Calcitonin gene-related
peptide (CGRP) has emerged as a key neuropeptide involved in the pathophysiology
of migraines. As reviewed in this manuscript, a number of small molecule
antagonists of the CGRP receptor have been developed for migraine therapy.
Incredibly, the majority of the clinical trials conducted have proven positive,
demonstrating the importance of this signalling pathway in migraine.
Unfortunately, a number of these molecules raised liver toxicity concerns when
used daily for as little as 7 days resulting in their discontinuation. Despite
the clear safety concerns, clinical trial data suggests that their intermittent
use remains a viable and safe alternative, with 2 molecules remaining in
clinical development (ubrogepant and rimegepant). Further, these proofs of
principle studies identifying CGRP as a viable clinical target have led to the
development of several CGRP or CGRP receptor-targeted monoclonal antibodies that
continue to show good clinical efficacy. Treatment of migraine is on the cusp of a new era with the development of drugs
that target the trigeminal sensory neuropeptide calcitonin gene-related peptide
(CGRP) or its receptor. Several of these drugs are expected to receive approval
for use in migraine headache in 2018 and 2019. CGRP-related therapies offer
considerable improvements over existing drugs as they are the first to be
designed specifically to act on the trigeminal pain system, they are more
specific and they seem to have few or no adverse effects. CGRP receptor
antagonists such as ubrogepant are effective for acute relief of migraine
headache, whereas monoclonal antibodies against CGRP (eptinezumab, fremanezumab
and galcanezumab) or the CGRP receptor (erenumab) effectively prevent migraine
attacks. As these drugs come into clinical use, we provide an overview of
knowledge that has led to successful development of these drugs. We describe the
biology of CGRP signalling, summarize key clinical evidence for the role of CGRP
in migraine headache, including the efficacy of CGRP-targeted treatment, and
synthesize what is known about the role of CGRP in the trigeminovascular system.
Finally, we consider how the latest findings provide new insight into the
central role of the trigeminal ganglion in the pathophysiology of migraine. INTRODUCTION: Migraine is a common and highly disabling neurological disorder
whose acute treatment remains problematic and unsatisfactory in a high
percentage of cases. Consequently, there remains a need for new symptomatic
therapies that can be easily handled by patients (i.e. by oral administration).
AREAS COVERED: This review reports on compounds currently under development for
the oral treatment of acute migraine attacks, focusing on
Calcitonin-Gene-Related-Peptide receptor antagonists, specifically ubrogepant
and rimegepant. This article is based on literature obtained from PubMed and
publicly available clinical trial data.
EXPERT OPINION: Both reviewed compounds meet the need for rapid and effective
pain control, combined with the control of associated bothersome symptoms while
also lacking significant adverse events and safety concerns. Though further
studies should assess the profile of these compounds comparatively with existing
and available treatments (namely triptans), the currently available data points
to these new therapies as being very promising new symptomatic oral treatments
of migraines. Migraine is a leading cause of disability worldwide. Approximately 15% of
Americans experience migraines. Most people who have migraines feel that people
who do not have them often underestimate their condition. Migraines affect
people's quality of life and ability to participate in work, family, and social
events. A new class of medication, calcitonin gene-related peptide (CGRP)
antagonists, has been approved for migraine prevention in adults. The newly
approved CGRP antagonists are erenumab, fremanezumab, and galcanezumab, while
eptinezumab looks to 2020 for approval. Lasmiditan, ubrogepant, and rimegepant
are currently emerging acute migraine therapies that may be added to the arsenal
of current migraine management. BACKGROUND: In the past decade, migraine research has identified novel drug
targets. In this review, we discuss recent data on emerging anti-migraine
therapies.
MAIN BODY: The development of ditans, gepants and anti-calcitonin gene-related
peptide monoclonal antibodies for the treatment of migraine is one of the
greatest advances in the migraine field. Lasmiditan, rimegepant and ubrogepant
will extend our therapeutic armamentarium for managing acute migraine attacks
when triptans are not effective or contraindicated due to cardiovascular
disorders. The monoclonal antibodies are migraine specific prophylactic drugs
with high responder rates and favorable adverse event profiles. Furthermore,
they offer convenient treatment regimens of 4- or 12-week intervals.
CONCLUSION: Collectively, novel migraine therapies represent a major progress in
migraine treatment and will undoubtedly transform headache medicine. Several lines of evidence pointed to an important role for CGRP in migraine.
These included the anatomic colocalization of CGRP and its receptor in sensory
fibers innervating pain-producing meningeal blood vessels, its release by
trigeminal stimulation, the observation of elevated CGRP in the cranial
circulation during migraine with normalization concomitant with headache relief
by sumatriptan, and translational studies with intravenous (IV) CGRP that evoked
migraine only in migraineurs. The development of small molecule CGRP receptor
antagonists (CGRP-RAs) that showed clinical antimigraine efficacy acutely and
prophylactically in randomized placebo-controlled clinical trials subsequently
gave definitive pharmacological proof of the importance of CGRP in migraine.
More recently, CGRP target engagement imaging studies using a CGRP receptor PET
ligand [11 C]MK-4232 demonstrated that there was no brain CGRP receptor
occupancy at clinically effective antimigraine doses of telcagepant, a
prototypic CGRP-RA. Taken together, these data indicated that (1) the
therapeutic site of action of the CGRP-RAs was peripheral not central; (2) that
IV CGRP had most likely evoked migraine through an action at sites outside the
blood-brain barrier; and (3) that migraine pain was therefore, at least in part,
peripheral in origin. The evolution of CGRP migraine science gave impetus to the
development of peripherally acting drugs that could modulate CGRP chronically to
prevent frequent episodic and chronic migraine. Large molecule biologic antibody
(mAb) approaches that are given subcutaneously to neutralize circulating CGRP
peptide (fremanezumab, galcanezumab) or block CGRP receptors (erenumab) have
shown consistent efficacy and tolerability in multicenter migraine prevention
trials and are now approved for clinical use. Eptinezumab, a CGRP neutralizing
antibody given IV, shows promise in late stage clinical development. Recently,
orally administered next-generation small molecule CGRP-RAs have been shown to
have safety and efficacy in acute treatment (ubrogepant and rimegepant) and
prevention (atogepant) of migraine, giving additional CGRP-based therapeutic
options for migraine patients. PURPOSE OF REVIEW: To review 5 new areas in primary headache disorders,
especially migraine and cluster headache.
RECENT FINDINGS: Calcitonin gene-related peptide (CGRP) receptor antagonists
(gepants-rimegepant and ubrogepant) and serotonin 5-HT1F receptor agonists
(ditans-lasmiditan) have completed phase 3 clinical trials and will soon offer
novel, effective, well-tolerated nonvasoconstrictor options to treat acute
migraine. CGRP preventive treatment is being revolutionized after the licensing
of 3 monoclonal antibodies (MABs), erenumab, fremanezumab, and galcanezumab,
with eptinezumab to follow, especially designed for migraine; they are effective
and well tolerated. For patients seeking a nondrug therapy, neuromodulation
approaches, single-pulse transcranial magnetic stimulation, noninvasive vagus
nerve stimulation (nVNS), and external trigeminal nerve stimulation, represent
licensed, well-tolerated approaches to migraine treatment. For the acute
treatment of episodic cluster headache, nVNS is effective, well tolerated, and
licensed; nVNS is effective and well tolerated in preventive treatment of
cluster headache. The CGRP MAB galcanezumab was effective and well tolerated in
a placebo-controlled trial in the preventive treatment of episodic cluster
headache. Sphenopalatine ganglion stimulation has been shown to be effective and
well tolerated in 2 randomized sham-controlled studies on chronic cluster
headache. Understanding the premonitory (prodromal) phase of migraine during
which patients experience symptoms such as yawning, tiredness, cognitive
dysfunction, and food cravings may help explain apparent migraine triggers in
some patients, thus offering better self-management.
SUMMARY: Headache medicine has made remarkable strides, particularly in
understanding migraine and cluster headache in the past 5 years. For the most
common reason to visit a neurologist, therapeutic advances offer patients
reduced disability and neurologists a rewarding, key role in improving the lives
of those with migraine and cluster headache. Ubrogepant (MK-1602) is a novel, oral, calcitonin gene-related peptide receptor
antagonist in clinical development with positive phase III outcomes for acute
treatment of migraine. This paper describes the population exposure-response
(E-R) modeling and simulations, which were used to inform the phase III
dose-selection rationale, based on ~ 800 participants pooled across two phase
IIb randomized dose-finding clinical trials. The E-R model describes the placebo
and ubrogepant treatment effects based on migraine pain end points (2-hour pain
relief and 2-hour pain freedom) at various dose levels. Sensitivity analyses
were conducted to evaluate various assumptions of placebo response in light of
the high placebo response observed in one phase II trial. A population
pharmacokinetic model describing the effect of formulations was included in the
E-R simulation framework to assess potential dose implications of a formulation
switch from phase II to phase III. Model-based simulations predict that a dose
of 25 mg or higher is likely to achieve significantly better efficacy than
placebo with desirable efficacy levels. The understanding of E-R helped support
the dose selection for the phase III clinical trials. BACKGROUND: Ubrogepant is an oral, small-molecule calcitonin gene-related
peptide receptor antagonist for acute migraine treatment.
METHODS: We conducted a randomized trial to evaluate the efficacy, safety, and
side-effect profile of ubrogepant. We assigned adults with migraine, with or
without aura, in a 1:1:1 ratio to receive an initial dose of placebo, ubrogepant
at a dose of 50 mg, or ubrogepant at a dose of 100 mg for treatment of a single
migraine attack, with the option to take a second dose. The coprimary efficacy
end points were freedom from pain at 2 hours after the initial dose and absence
of the most bothersome migraine-associated symptom at 2 hours. Secondary end
points included pain relief (at 2 hours), sustained pain relief (from 2 to 24
hours), sustained freedom from pain (from 2 to 24 hours), and absence of
symptoms associated with migraine (photophobia, phonophobia, and nausea) at 2
hours.
RESULTS: A total of 1672 participants were enrolled; 559 were assigned to
receive placebo, 556 to receive 50 mg of ubrogepant, and 557 to receive 100 mg
of ubrogepant. The percentage of participants who had freedom from pain at 2
hours was 11.8% in the placebo group, 19.2% in the 50-mg ubrogepant group
(P = 0.002, adjusted for multiplicity, for the comparison with placebo), and
21.2% in the 100-mg ubrogepant group (P<0.001). The percentage of participants
who had freedom from the most bothersome symptom at 2 hours was 27.8% in the
placebo group, 38.6% in the 50-mg ubrogepant group (P = 0.002), and 37.7% in the
100-mg ubrogepant group (P = 0.002). Adverse events within 48 hours after the
initial or optional second dose were reported in 12.8% of participants in the
placebo group, in 9.4% in the 50-mg ubrogepant group, and in 16.3% in the 100-mg
ubrogepant group. The most common adverse events were nausea, somnolence, and
dry mouth (reported in 0.4 to 4.1%); these events were more frequent in the
100-mg ubrogepant group (reported in 2.1 to 4.1%). Serious adverse events
reported within 30 days in the ubrogepant groups included appendicitis,
spontaneous abortion, pericardial effusion, and seizure; none of the events
occurred within 48 hours after the dose.
CONCLUSIONS: A higher percentage of participants who received ubrogepant than of
those who received placebo had freedom from pain and absence of the most
bothersome symptom at 2 hours after the dose. The most commonly reported adverse
events were nausea, somnolence, and dry mouth. Further trials are needed to
determine the durability and safety of ubrogepant for acute migraine treatment
and to compare it with other drugs for migraine. (Funded by Allergan;
ClinicalTrials.gov number, NCT02828020.). |
Is Selinexor effective for multiple myeloma? | Yes, Selinexor is effective for multiple myeloma. | This review discusses the landmark studies in the field of multiple myeloma (MM)
which were presented at American society of hematology annual meeting, 2016.
There were contrary results from two large phase III trials (one from US and one
from Europe) that evaluated the role of additional interventions like tandem
autologous transplant (ASCT) and consolidation after induction therapy followed
by ASCT in newly diagnosed MM (NDMM) patients, but there were critical
differences between the two studies. Novel agents like carfilzomib and ixazomib
proved to be of benefit when used as induction and post ASCT consolidation and
maintece in NDMM. The early data on subcutaneous administration of
daratumumab (DARA) looked promising. The high rate of minimal residual disease
negativity after using DARA even in relapsed/refractory MM (RRMM) setting
reinforces the benefit of targeting CD38. The responses seen with venetoclax in
RRMM with t(11;14)(high BCL-2, low BCL-XL and MCL-1) and selinexor in
penta-refractory myeloma which fulfills the FDA category of unmet need, opens up
newer options for these patients. BCMA CAR-T infusion shows encouraging results
in advanced refractory myeloma patients. Despite enormous advances, management of multiple myeloma (MM) remains
challenging. Multiple factors impact the decision to treat or which regimen to
use at MM relapse/progression. Recent major randomized controlled trials (RCTs)
showed widely varying progression-free survivals (PFS), ranging from a median of
4 months (MM-003) to 23.6 months (ASPIRE). Based on these RCTs, next-generation
proteasome inhibitors (carfilzomib and ixazomib), next-generation
immunomodulatory agent (pomalidomide), and monoclonal antibodies (elotuzumab and
daratumumab) were approved for relapsed and refractory MM. Daratumumab,
targeting CD38, has multiple mechanisms of action including modulation of the
immunosuppressive bone marrow micro-environment. In addition to the remarkable
single agent activity in refractory MM, daratumumab produced deep responses and
superior PFS in MM when combined with lenalidomide/dexamethasone, or
bortezomib/dexamethasone. Other anti-CD38 antibodies, such as isatuximab and
MOR202, are undergoing assessment. Elotuzumab, targeting SLAMF7, yielded
superior response rates and PFS when combined with lenalidomide/dexamethasone.
New combinations of these next generation novel agents and/or antibodies are
undergoing clinical trials. Venetoclax, an oral BH3 mimetic inhibiting BCL2,
showed single agent activity in MM with t(11;14), and is being studied in
combination with bortezomib/dexamethasone. Selinexor, an Exportin-1 inhibitor,
yielded promising results in quad- or penta-refractory MM including patients
resistant to daratumumab. Pembrolizumab, an anti-PD1 check-point inhibitor, is
being tested in combination with lenalidomide/dexamethasone or
pomalidomide/dexamethasone. Chimeric antigen receptor-T cells targeting B-cell
maturation antigen have yielded deep responses in RRMM. Finally, salvage
autologous stem cell transplantation (ASCT) remains an important treatment in MM
relapsing/progressing after a first ASCT. Herein, the clinical trial data of
these agents are summarized, cautious interpretation of RCTs highlighted, and
algorithm for salvage treatment of relapse/refractory MM proposed. Purpose Selinexor, a first-in-class, oral, selective exportin 1 (XPO1)
inhibitor, induces apoptosis in cancer cells through nuclear retention of tumor
suppressor proteins and the glucocorticoid receptor, along with inhibition of
translation of oncoprotein mRNAs. We studied selinexor in combination with
low-dose dexamethasone in patients with multiple myeloma refractory to the most
active available agents. Patients and Methods This phase II trial evaluated
selinexor 80 mg and dexamethasone 20 mg, both orally and twice weekly, in
patients with myeloma refractory to bortezomib, carfilzomib, lenalidomide, and
pomalidomide (quad-refractory disease), with a subset also refractory to an
anti-CD38 antibody (penta-refractory disease). The primary end point was overall
response rate (ORR). Results Of 79 patients, 48 had quad-refractory and 31 had
penta-refractory myeloma. Patients had received a median of seven prior
regimens. The ORR was 21% and was similar for patients with quad-refractory
(21%) and penta-refractory (20%) disease. Among patients with high-risk
cytogenetics, including t(4;14), t(14;16), and del(17p), the ORR was 35% (six of
17 patients). The median duration of response was 5 months, and 65% of
responding patients were alive at 12 months. The most common grade ≥ 3 adverse
events were thrombocytopenia (59%), anemia (28%), neutropenia (23%),
hyponatremia (22%), leukopenia (15%), and fatigue (15%). Dose interruptions for
adverse events occurred in 41 patients (52%), dose reductions occurred in 29
patients (37%), and treatment discontinuation occurred in 14 patients (18%).
Conclusion The combination of selinexor and dexamethasone has an ORR of 21% in
patients with heavily pretreated, refractory myeloma with limited therapeutic
options. Selinexor is an oral inhibitor of the nuclear export protein exportin 1.
Preclinical studies demonstrated synergistic antimyeloma activity between
selinexor and proteasome inhibitors (PI) through suppression of NF-κB signaling
and nuclear retention of tumor suppressor proteins. We tested selinexor in
combination with low-dose bortezomib and dexamethasone (SVd) for the treatment
of relapsed or refractory multiple myeloma (MM). The primary objectives of this
study were to determine the safety profile, overall response rate (ORR), and a
recommended phase 2 dose (RP2D) of SVd. We enrolled 42 patients to receive
selinexor (60, 80, or 100 mg orally) plus bortezomib (1.3 mg/m2 subcutaneously)
and dexamethasone (20 mg orally) once or twice weekly in 21- or 35-day cycles.
Patients had a median of 3 (range 1-11) prior lines of therapy, and 50% were
refractory to a PI. Treatment-related grade 3 or 4 adverse events reported in
≥10% of patients were thrombocytopenia (45%), neutropenia (24%), fatigue (14%),
and anemia (12%). Incidence (4 patients, 10%) and grade (≤2) of peripheral
neuropathy were low. The ORR for the entire population was 63%: 84% ORR for PI
nonrefractory and 43% for PI-refractory patients. The median progression-free
survival for all patients was 9.0 months; 17.8 months for PI nonrefractory, and
6.1 months for PI refractory. SVd treatment produced high response rates in
patients with relapsed or refractory MM, including borezomib-refractory MM, with
no unexpected side effects. The RP2D is selinexor (100 mg once weekly),
bortezomib (1.3 mg/m2 once weekly for 4 weeks), and dexamethasone (40 mg once
weekly) per 35-day cycle. This trial was registered at www.clinicaltrials.gov as
#NCT02343042. The FDA granted accelerated approval to selinexor plus low-dose dexamethasone
for triple-class refractory multiple myeloma, despite an advisory panel's
concerns about the drug's toxicity and the lack of randomized clinical data. Objective: To review the pharmacology, pharmacokinetics, efficacy, and safety of
selinexor for management of relapsed multiple myeloma (MM). Data Sources: A
literature search was performed of PubMed and MEDLINE databases (January 1,
2000, to November 14, 2019), abstracts from the American Society of Hematology
and the American Society of Clinical Oncology, and ongoing studies from US
National Institutes of Health ClinicalTrials.gov. Queries were performed using
key words selinexor, SINE, XPO1, and Xpovio.Study Selection/Data Extraction:
Human and animal studies related to the pharmacology, pharmacokinetics,
efficacy, and safety of selinexor were identified. Data Synthesis: Although
numerous advances have been made in MM management, there remains an unmet need
for treatment of heavily relapsed/refractory disease. Selinexor is a
first-in-class selective inhibitor of nuclear export, which, through inhibition
of exportin-1, causes accumulation of tumor suppressor proteins, reduction in
oncoproteins, and apoptosis of plasma cells. Selinexor exhibited an overall
response in 26% of patients with multiply relapsed MM. Median progression-free
survival was 3.7 months, and overall survival was 8.6 months. Common adverse
effects include thrombocytopenia, neutropenia, fatigue, and nausea. Ongoing
studies are investigating combination therapies utilizing selinexor. Relevance
to Patient Care and Clinical Practice: This review describes the efficacy,
safety, and clinical applicability of selinexor, a novel agent with potential to
meet an unmet need in refractory MM. Conclusion: Selinexor has demonstrated
activity in a heavily refractory patient population. Given the adverse effect
profile and associated costs, additional studies are needed to further elucidate
the appropriate clinical scenario and combinations for selinexor use. |
What is the protein product of the gene GBA2? | The GBA2 gene encodes the non-lysosomal glucosylceramidase (NLGase), an enzyme that catalyzes the conversion of glucosylceramide (GlcCer) to ceramide and glucose. | The non-lysosomal glucosylceramidase GBA2 catalyzes the hydrolysis of
glucosylceramide to glucose and ceramide. Loss of GBA2 function results in
accumulation of glucosylceramide. Mutations in the human GBA2 gene have been
associated with hereditary spastic paraplegia (HSP) and autosomal-recessive
cerebellar ataxia (ARCA). Patients suffering from these disorders exhibit
impaired locomotion and neurological abnormalities. GBA2 mutations found in
these patients have been proposed to impair GBA2 function. However, the
molecular mechanism underlying the occurrence of mutations in the GBA2 gene and
the development of locomotor dysfunction is not well-understood. In this review,
we aim to summarize recent findings regarding mutations in the GBA2 gene and
their impact on GBA2 function in health and disease. Hereditary spastic paraplegias (HSPs) are a heterogeneous group of neurological
disorders characterized primarily by a pyramidal syndrome with lower limb
spasticity, which can manifest as pure HSP or associated with a number of
neurological or non-neurological signs (i.e., complicated HSPs). The clinical
variability of HSPs is associated with a wide genetic heterogeneity, with more
than eighty causative genes known. Recently, next generation sequencing (NGS)
has allowed increasing genetic definition in such a heterogeneous group of
disorders. We report on a 56- year-old man affected by sporadic complicated HSP
consisting of a pyramidal syndrome, cerebellar ataxia, congenital cataract, pes
cavus, axonal sensory-motor peripheral neuropathy and cognitive decline. Brain
MRI showed cerebellar atrophy and thin corpus callosum. By NGS we found a novel
homozygous biallelic c.452-1G > C mutation in the b-glucosidase 2 gene (GBA2),
known to be causative for autosomal recessive hereditary spastic paraplegia type
46 (SPG46). The rarity of this inherited form besides reporting on a novel
mutation, expands the genetic and clinical spectrum of SPG46 related HSP. Author information:
(1)Biochemical Genetics Department, The Cyprus Institute of Neurology and
Genetics, Nicosia 1683, Cyprus. [email protected].
(2)Cyprus School of Molecular Medicine, Nicosia 1683, Cyprus. [email protected].
(3)Department of Medical Biotechnology and Translational Medicine, University of
Milano, 20122 Milano, Italy. [email protected].
(4)Biochemical Genetics Department, The Cyprus Institute of Neurology and
Genetics, Nicosia 1683, Cyprus. [email protected].
(5)Cyprus School of Molecular Medicine, Nicosia 1683, Cyprus.
[email protected].
(6)Cyprus School of Molecular Medicine, Nicosia 1683, Cyprus. [email protected].
(7)Neurogenetics Department, The Cyprus Institute of Neurology and Genetics,
Nicosia 1683, Cyprus. [email protected].
(8)Department of Medical Biotechnology and Translational Medicine, University of
Milano, 20122 Milano, Italy. [email protected].
(9)Cyprus School of Molecular Medicine, Nicosia 1683, Cyprus.
[email protected].
(10)Neurology Clinic C, The Cyprus Institute of Neurology and Genetics, Nicosia
1683, Cyprus. [email protected].
(11)Department of Medical Biotechnology and Translational Medicine, University
of Milano, 20122 Milano, Italy. [email protected].
(12)Cyprus School of Molecular Medicine, Nicosia 1683, Cyprus.
[email protected].
(13)Neurology Clinic D, The Cyprus Institute of Neurology and Genetics, Nicosia
1683, Cyprus. [email protected].
(14)Department of Medical Biotechnology and Translational Medicine, University
of Milano, 20122 Milano, Italy. [email protected].
(15)Department of Medical Biotechnology and Translational Medicine, University
of Milano, 20122 Milano, Italy. [email protected].
(16)Cyprus School of Molecular Medicine, Nicosia 1683, Cyprus. [email protected].
(17)Neurogenetics Department, The Cyprus Institute of Neurology and Genetics,
Nicosia 1683, Cyprus. [email protected]. |
Are there lncRNAs that control the extent of neuronal outgrowth? | Yes. there are lncRNAs which regulate the extent of neuronal outgrowth. | |
Can the radiation of cellphones be dangerous? | two sets of more recent studies with longer exposure duration: the Interphone studies and the Swedish studies led by Dr. Lennart Hardell. The recent studies reach very different conclusions. With four exceptions the industry-funded Interphone studies found no increased risk of brain tumors from cellphone use, while the Swedish studies, independent of industry funding, reported numerous findings of significant increased brain tumor risk from cellphone and cordless phone use. | This paper reviews the results of early cellphone studies, where exposure
duration was too short to expect tumorigenesis, as well as two sets of more
recent studies with longer exposure duration: the Interphone studies and the
Swedish studies led by Dr. Lennart Hardell. The recent studies reach very
different conclusions. With four exceptions the industry-funded Interphone
studies found no increased risk of brain tumors from cellphone use, while the
Swedish studies, independent of industry funding, reported numerous findings of
significant increased brain tumor risk from cellphone and cordless phone use. An
analysis of the data from the Interphone studies suggests that either the use of
a cellphone protects the user from a brain tumor, or the studies had serious
design flaws. Eleven flaws are identified: (1) selection bias, (2) insufficient
latency time, (3) definition of 'regular' cellphone user, (4) exclusion of young
adults and children, (5) brain tumor risk from cellphones radiating higher power
levels in rural areas were not investigated, (6) exposure to other transmitting
sources are excluded, (7) exclusion of brain tumor types, (8) tumors outside the
cellphone radiation plume are treated as exposed, (9) exclusion of brain tumor
cases because of death or illness, (10) recall accuracy of cellphone use, and
(11) funding bias. The Interphone studies have all 11 flaws, and the Swedish
studies have 3 flaws (8, 9 and 10). The data from the Swedish studies are
consistent with what would be expected if cellphone use were a risk for brain
tumors, while the Interphone studies data are incredulous. If a risk does exist,
the public health cost will be large. These are the circumstances where
application of the Precautionary Principle is indicated, especially if low-cost
options could reduce the absorbed cellphone radiation by several orders of
magnitude. |
Does metformin has as an antitumor effect? | Yes, The anti-tumor effect of metformin is widely known. | Metformin is a standard clinical drug used to treat type 2 diabetes mellitus
(T2DM) and polycystic ovary syndrome. Recently, epidemiological studies and
meta-analyses have revealed that patients with T2DM have a lower incidence of
tumor development than healthy controls and that patients diagnosed with cancer
have a lower risk of mortality when treated with metformin, demonstrating an
association between metformin and tumorigenesis. In vivo and in vitro studies
have revealed that metformin has a direct antitumor effect, which may depress
tumor proliferation and induce the apoptosis, autophagy and cell cycle arrest of
tumor cells. The mechanism underpinning the antitumor effect of metformin has
not been well established. Studies have demonstrated that reducing insulin and
insulin-like growth factor levels in the peripheral blood circulation may lead
to the inhibition of phosphoinositide 3-kinase/Akt/mechanistic target of
rapamycin (mTOR) signaling or activation of AMP-activated protein kinase, which
inhibits mTOR signaling, a process that may be associated with the antitumor
effect of metformin. The present review primarily focuses on the recent progress
in understanding the function of metformin in tumor development. OBJECTIVE: Metformin, an antidiabetic drug, inhibits the endometrial cancer cell
growth in vivo by improving the insulin resistance; however, its mechanism of
action is not completely understood. Protein phosphatase 2A (PP2A) is a
serine/threonine phosphatase associated with insulin resistance and type 2
diabetes, and its inhibition restores the insulin resistance. This study
investigated the antitumor effect of metformin on endometrial cancer with a
focus on PP2A.
METHODS: Metformin (1,500-2,250 mg/day) was preoperatively administered to
patients with endometrial cancer for 4 to 6 weeks. Expression of the PP2A
regulatory subunits, 4 (PPP2R4) and B (PP2A-B), was evaluated using real-time
polymerase chain reaction (RT-PCR) and immunohistochemistry (IHC) using paired
specimens obtained before and after metformin treatment. The effect of PPP2R4
inhibition with small interfering RNA was evaluated in the endometrial cancer
cell lines HEC265 and HEC1B. P values of < .05 were considered statistically
significant.
RESULTS: Preoperative metformin treatment significantly reduced the expression
of PP2A-B, as determined using IHC, and the mRNA expression of PPP2R4, as
determined using RT-PCR, in the patients with endometrial cancer. However,
metformin could not directly alter the PPP2R4 mRNA levels in the endometrial
cancer cell lines in vitro. PPP2R4 knockdown reduced the proliferation and
induced the apoptosis by activating caspases 3/7 in HEC265 and HEC1B cells.
CONCLUSIONS: Downregulation of the PP2A-B subunit, including PPP2R4, is an
important indirect target of metformin. Inhibition of PP2A may be an option for
the treatment of endometrial cancer patients with insulin resistance.
TRIAL REGISTRATION: This trial is registered with UMIN-CTR (number
UMIN000004852). Author information:
(1)Epidemiology Unit, Local Health Authority of Reggio Emilia-IRCCS, Reggio
Emilia, Italy. Electronic address: [email protected].
(2)Epidemiology Unit, Local Health Authority of Reggio Emilia-IRCCS, Reggio
Emilia, Italy. Electronic address: [email protected].
(3)Epidemiology Unit, Local Health Authority of Reggio Emilia-IRCCS, Reggio
Emilia, Italy. Electronic address: [email protected].
(4)Epidemiology Unit, Local Health Authority of Reggio Emilia-IRCCS, Reggio
Emilia, Italy; Specialization School of Hygiene and Preventive Medicine,
Department of Biomedical, Metabolic and Neural Sciences, University of Modena
and Reggio Emilia, Modena, Italy; Clinical and Experimental Medicine PhD
Program, University of Modena and Reggio Emilia, Modena, Italy. Electronic
address: [email protected].
(5)Epidemiology Unit, Local Health Authority of Reggio Emilia-IRCCS, Reggio
Emilia, Italy. Electronic address: [email protected].
(6)Primary Health Care, Local Health Authority of Reggio Emilia-IRCCS, Reggio
Emilia, Italy. Electronic address: [email protected].
(7)Epidemiology Unit, Local Health Authority of Reggio Emilia-IRCCS, Reggio
Emilia, Italy. Electronic address: [email protected].
(8)Epidemiology Unit, Local Health Authority of Reggio Emilia-IRCCS, Reggio
Emilia, Italy. Electronic address: [email protected].
(9)Department of Internal Medicine, Hospital of Montecchio, Local Health
Authority of Reggio Emilia-IRCCS, Reggio Emilia, Italy. Electronic address:
[email protected]. Author information:
(1)Department of Hepatobiliary Surgery, The First Affiliated Hospital, Xi'an
Jiaotong University, Xi'an 710061, China. Electronic address:
[email protected].
(2)Department of Hepatobiliary Surgery, The First Affiliated Hospital, Xi'an
Jiaotong University, Xi'an 710061, China. Electronic address:
[email protected].
(3)Department of Hepatobiliary Surgery, The First Affiliated Hospital, Xi'an
Jiaotong University, Xi'an 710061, China. Electronic address:
[email protected].
(4)Department of Hepatobiliary Surgery, The First Affiliated Hospital, Xi'an
Jiaotong University, Xi'an 710061, China. Electronic address:
[email protected].
(5)Department of Hepatobiliary Surgery, The First Affiliated Hospital, Xi'an
Jiaotong University, Xi'an 710061, China. Electronic address:
[email protected].
(6)Department of Hepatobiliary Surgery, The First Affiliated Hospital, Xi'an
Jiaotong University, Xi'an 710061, China. Electronic address:
[email protected].
(7)Department of Hepatobiliary Surgery, The First Affiliated Hospital, Xi'an
Jiaotong University, Xi'an 710061, China. Electronic address:
[email protected].
(8)Department of Hepatobiliary Surgery, The First Affiliated Hospital, Xi'an
Jiaotong University, Xi'an 710061, China. Electronic address:
[email protected].
(9)Department of Hepatobiliary Surgery, The First Affiliated Hospital, Xi'an
Jiaotong University, Xi'an 710061, China. Electronic address:
[email protected].
(10)Department of Hepatobiliary Surgery, The First Affiliated Hospital, Xi'an
Jiaotong University, Xi'an 710061, China. Electronic address:
[email protected]. |
Can radiation induced meningiomas be treated with radiosurgery? | Yes, radiation induced meningiomas be treated with radiosurgery. Radiosurgery provides satisfactory control of radiation induced meningiomas. | OBJECTIVE Multiple meningiomas account for 1%-10% of meningiomas. This study
describes epidemiological aspects of the disease and its management, which is
more challenging than for single tumors. METHODS A consecutive series of adult
patients with ≥ 2 spatially separated meningiomas was reviewed. Patients with
neurofibromatosis Type 2 were excluded. The authors collected clinical, imaging,
histological, and treatment data to obtain information on epidemiology,
management options, and outcomes of active treatment and surveillance. RESULTS A
total of 133 consecutive patients were included over 25 years, with a total of
395 synchronous and 53 metachronous meningiomas, and a median of 2 tumors per
patient. One hundred six patients had sporadic disease, 26 had radiation-induced
disease, and 1 had familial meningiomatosis. At presentation, half of the
patients were asymptomatic. In terms of their maximum cross-sectional diameter,
the tumors were small (≤ 2 cm) in 67% and large (> 4 cm) in 11% of the
meningiomas. Fifty-four patients had upfront treatment, and 31 had delayed
treatment after an observation period (mean 4 years). One in 4 patients had ≥ 2
meningiomas treated. Overall, 64% of patients had treatment for 142 tumors-67
with surgery and 18 with radiotherapy alone. The mean follow-up was 7 years,
with 13% of treated patients receiving salvage therapy. Approximately 1 in 4
patients who underwent surgery had ≥ 1 WHO Grade II or III meningioma.
Meningiomas of different histological subtypes and grades in the same patient
were not uncommon. CONCLUSIONS Multiple meningiomas are often asymptomatic,
probably because the majority are small and a significant proportion are induced
by radiation. Approximately two-thirds of patients with multiple meningiomas
require therapy, but only one-third of all meningiomas need active treatment.
The authors recommend surveillance for stable and asymptomatic meningiomas and
therapy for those that are symptomatic or growing. Trigeminal neuralgia is a known symptom of the tumors and aberrant vessels near
the trigeminal nerve and the tentorial notch. There are very few reports of
delayed development of trigeminal neuralgia after radiosurgical treatment of a
tumor in these areas. This is a case report of a patient treated with
radiosurgery for radiation induced meningiomas, 30 years after childhood whole
brain radiation. The largest tumor was adjacent to the pons and left trigeminal
nerve but did not cause any direct neurologic symptoms or facial pain. Nine
months after radiosurgical treatment of the tumors, the patient developed left
sided typical trigeminal facial pain and magnetic resoce imaging (MRI)
demonstrated the marked reduction in the tumor size. The patient was
subsequently treated with radiosurgery to the Gasserian ganglion with a
resolution of facial pain. This article reviews the unique characteristics and
unusual response to the radiation induced meningiomas to radiosurgery. This is a
case of rapid shrinkage of the tumor seen on follow-up MRI scans, concurrent
with the development of facial pain, suggests that the rapid shrinkage led to
traction on adhesions and related microvasculature changes adjacent to the tumor
and trigeminal nerve roots causing the subsequent trigeminal neuralgia. |
What is known about ROS production in relation to UVR? | Skin exposure to ultraviolet radiation (UVR) may induce the production of reactive oxygen species (ROS) which cause oxidative stress, DNA damage, and alteration of fibroblasts and collagen responsible for skin photoaging. | Ultraviolet radiation (UVR) exposure causes various injurious effects to human
skin by generating reactive oxygen species (ROS). Excessive ROS production can
lead to oxidative stress which may damage cellular components like lipids and
proteins and causing photoaging. The use of natural photochemopreventive agents
with antioxidant properties is an important alternative to improve the
effectiveness of sunscreens and reduce skin photodamage. A crude extract (CE)
from the leaves of Arrabidaea chica underwent partition by a liquid-liquid
method. The hexane fraction (FH), chloroform fraction (FC), and ethyl acetate
fraction (FEA) were obtained. The antioxidant capacity of the CE, FH, FC, and
FEA was studied in a cell-free system using the 2,2-diphenyl-1-picrylhydrazyl
(DPPH) method and the xanthine/luminol/xanthine oxidase system. The FC had the
best antioxidant activity. We also evaluated the photochemoprotective effect of
A. chica in protecting L929 fibroblasts against UV-A- and UV-B-induced cell
damage. A. chica inhibited the extended production of ROS up to 3h.
Posttreatment with the CE and FC attenuated UV-induced cell damage through
scavenging mechanisms, including the quenching of intracellular ROS and
mitochondrial O2- and preventing lipid peroxidation. These results suggest that
A. chica may be a promising non-sunscreen photoprotector that can improve the
effectiveness of commercial sunscreens. BACKGROUND: Studies have shown that skin exposure to ultraviolet radiation (UVR)
results in the formation of reactive oxygen species (ROS), thus altering the
cellular function. The human epidermal skin layer is mainly composed of
keratinocytes, which is damaged by UV-B radiation-induced intracellular
oxidative stress. Neferine is an alkaloid extract from lotus seed embryos and is
known to promote antioxidant activity.
OBJECTIVE: In this study for the first time, we investigated the photoprotective
action of neferine, against UV-B-produced oxidative damage in human epidermal
keratinocytes (HEKs).
METHODS: We established an in Vitro study model using HEKs. Cellular viability
was determined by MMT assay kits. The intracellular oxidative stress was
measured using ROS and malondialdehyde (MDA) assay kits. Endogenous antioxidants
were measured by superoxide dismutase (SOD) and glutathione peroxidase (GPx)
assay kits. Photoprotective nature of neferine was further evaluated by
analyzing the morphological and ultrastructural alterations in keratinocytes.
RESULTS: Neferine inhibit the UV-B-mediated increase in ROS and MDA levels in
pretreated keratinocytes. The antioxidants, SOD and GPx activities were
significantly high in neferine pretreated UV-B groups. Mitochondrial and
endoplasmic reticulum damage were less evident in neferine-pretreated UV-B
groups as compared with the control group, which might be associated with
reduced oxidative stress and lipid peroxidation.
CONCLUSION: Taken together, our results suggest that neferine can prevent
UV-B-induced oxidative damage and may thus be a potential agent for prevention
and treatment of skin damage and photoaging. Our daily exposure to ultraviolet radiation (UVR) results in the production of
reactive oxygen species (ROS), lipids, proteins and DNA damage and alteration in
fibroblast structure, thus contributing to skin photoaging. For this reason, the
use of natural bioactive compounds with antioxidant activity could be a
strategic tool to overcome ultraviolet A (UV-A) induced deleterious effect.
Neferine is an alkaloid extract from the seed embryos of lotus (Nelumbo nucifera
Gaertn). In the present study, we report the protective effect of neferine
against UV-A induced oxidative stress and photoaging in human dermal fibroblasts
(HDFs). HDFs subjected to UV-A irradiation showed increased production of ROS
and malondialdehyde (MDA). Furthermore, it depleted the cellular enzymatic
antioxidant superoxide dismutase (SOD) and non-enzymatic antioxidant glutathione
peroxidase (GPx). On the other hand, HDFs treated with neferine followed by UV-A
irradiation reversed the process, reduced the ROS and lipid peroxidation and
restored the antioxidants pool. Moreover, neferine treatment significantly
inhibited UV-A induced matrix metalloproteinase-1 (MMP-1) expression in HDFs.
Remarkable morphological and ultrastructural alterations observed in HDFs upon
UV-A irradiation, were also reduced with neferine treatment. Taken together, our
results suggest that neferine has strong antioxidative and photoprotective
properties and thus may be a potential agent for the prevention and treatment of
UV-A mediated skin photoaging. |
Which drugs used in the treatment of Systemic Lupus Erythematosus are targeting granulocytes? | Epratuzumab, a humanized monoclonal antibody against disialoganglioside, is the only officially approved treatment for the treatment of Systemic Lupus Erythematosus.Food and Drug Administration approval of SLE treatment with rituximab; however, more research is required before a large-scale application for clinical decision-making can be recommended. | This study demonstrates that extramedullary hematopoiesis occurs in livers of
adult lpr mice and, after treatment with each of three xenobiotic
compounds--phenobarbital, cyproterone acetate, and nafenopin--it includes
granulopoiesis. lpr mice are used as a model of the human disease systemic lupus
erythematosus (SLE). The develop a syndrome very similar to that of human
sufferers. In untreated lpr mice, mononuclear white blood cells were discernible
in hepatic sinusoidal foci; T and B lymphocytes were distinguished from each
other by immunocytochemistry at light microscope level. After treatment with any
of the xenobiotic compounds, immunolabeling demonstrated the additional presence
of granulocytes in foci, and, at electron microscope level neutrophils,
eosinophils and their precursors were clearly recognizable. Myelopathy manifested clinically as acute longitudinal or transverse myelitis
constitutes one of the most severe and rare neuropsychiatric manifestations of
systemic lupus erythematosus (SLE) (1-3% of patients). Myelitis has been
observed less commonly in other connective tissue diseases, mostly in
antiphospholipid syndrome, and rarely in Sjögren's syndrome, Behçet's disease
and mixed connective tissue disease. Acute transverse myelitis (ATM) may also be
present in diseases of various etiology, including multiple sclerosis,
sarcoidosis, infectious diseases and maligcies. Myelitis in SLE is manifested
as a dramatic spinal cord injury leading to paralysis or muscular paresis,
sensory deficits, and smooth muscle dysfunction usually in the form of sphincter
dysfunction. The imaging technique of choice in case of suspected ATM is
magnetic resoce imaging with intravenous contrast agent (gadolinium
diethylenetriamine-pentaacid). Cerebrospinal fluid (CSF) examination in patients
with ATM in the course of SLE indicate usually pleocytosis with prevalence of
granulocytes, increased protein levels, low glucose levels, significantly
hindering differential diagnosis in the early stage of the disease. Observations
made by the authors (2 female patients with SLE) show that antibodies specific
to SLE can be found in the CSF collected in the acute phase of myelitis. These
observations have not yet been confirmed by other researchers. Early
introduction of intravenous immunosuppression with large doses of
cyclophosphamide and glucocorticosteroids improves the long-term prognosis.
Other therapeutic approaches have been also used in more severe cases. Even with
appropriate therapy, prognosis in this disease is uncertain. Anti-neutrophil cytoplasmic antibodies (ANCA) are a family of autoantibodies
that react with proteins predomitly expressed in cytoplasmic granules of
polymorphonuclear neutrophil granulocytes (PMNs). ANCA was initially detected
using indirect immunofluorescence, allowing for different patterns such as
p-ANCA (perinuclear) and c-ANCA (cytoplasmic) to be distinguished. Today it is
common to detect the antibodies by immunochemical assays such as ELISA using
purified proteins as antigens. The strongest association with ANCA is found in
the pauci-immune small vessel vasculitides granulomatosis with polyangiitis
(GPA) and microscopic polyangiitis (MPA). There is compelling evidence that ANCA
contributes to the pathogenesis in these conditions. ANCA also occurs in 30%-40%
of patients with eosinophilic granulomatosis with polyangiitis (EGPA) and
anti-GBM disease, but is uncommon in other forms of vasculitis. ANCA with
different specificities have been described with varying frequencies in diseases
such as systemic lupus erythematosus (SLE), rheumatoid arthritis, inflammatory
bowel disease, endocarditis, chronic infections and hematopoietic maligcies.
ANCA can also develop as an adverse event during pharmacological treatment.
These entities are treated quite differently, with therapies ranging from
immunosuppressive agents over antibiotics to simply removing the causative drug.
A positive ANCA test thus requires a careful diagnostic work-up. |
What is PWMScan? | Transcription factors regulate gene expression by binding to specific short DNA sequences of 5-20 bp to regulate the rate of transcription of genetic information from DNA to messenger RNA. PWMScan is a fast web-based tool to scan server-resident genomes for matches to a user-supplied PWM or transcription factor binding site model from a public database. | SUMMARY: Transcription factors regulate gene expression by binding to specific
short DNA sequences of 5-20 bp to regulate the rate of transcription of genetic
information from DNA to messenger RNA. We present PWMScan, a fast web-based tool
to scan server-resident genomes for matches to a user-supplied PWM or
transcription factor binding site model from a public database.
AVAILABILITY AND IMPLEMENTATION: The web server and source code are available at
http://ccg.vital-it.ch/pwmscan and https://sourceforge.net/projects/pwmscan,
respectively.
SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics
online. |
Is there a BRCA mutation analysis in the Greek population? | Yes. Molecular analysis of the BRCA1 and BRCA2 genes in 898 Greek families was performed using Sanger sequencing or Next Generation Sequencing for the detection of small insertion/deletion frameshift, nonsynonymous, truncating and splice-site alterations and MLPA for the detection of large genomic rearrangements. In total, a pathogenic mutation was identified in 12.9% of 898 families analyzed. Of the 116 mutations identified in total 9% were novel and 14.7% were large genomic rearrangements. | Germline mutations in the BRCA1 and BRCA2 genes are associated with hereditary
predisposition to breast and ovarian cancer. Sensitive and accurate detection of
BRCA1 and BRCA2 mutations is crucial for personalized clinical management of
individuals affected by breast or ovarian cancer, and for the identification of
at-risk healthy relatives. We performed molecular analysis of the BRCA1 and
BRCA2 genes in 898 Greek families, using Sanger sequencing or Next Generation
Sequencing for the detection of small insertion/deletion frameshift,
nonsynonymous, truncating and splice-site alterations and MLPA for the detection
of large genomic rearrangements. In total, a pathogenic mutation was identified
in 12.9% of 898 families analyzed. Of the 116 mutations identified in total 9%
were novel and 14.7% were large genomic rearrangements. Our results indicate
that different types of mutational events in the BRCA1 and BRCA2 genes are
responsible for the hereditary component of breast/ovarian cancer in the Greek
population. Therefore the methodology used in the analysis of Greek patients
must be able to detect both point and small frameshift mutations in addition to
large genomic rearrangements across the entire coding region of the two genes. |
What is the basis of the DamID experimental protocol? | Dam Identification (DamID) system induced by Cre recombinase using Lamin B1 and mouse embryonic fibroblasts. This inducible system will help to generate genome-wide profiles of chromatin proteins in given cell types and tissues with no need to dissect tissues from organs or separate cells from tissues, which is achieved by using specific regulatory DNA elements and due to the high sensitivity of the method. DNA adenine methyltransferase identification (DamID) has emerged as one of the most comprehensive and versatile methods available for profiling protein-DNA interactions on a genomic scale. Recently, a novel methylation-based tagging technique, termed DamID (DNA adenine methyltransferase identification), has emerged as a powerful tool to decipher transcriptional networks, to study chromatin-associated proteins, and to monitor higher-order chromatin organization on a genome-wide scale. We show here that the in vivo methylation-based tagging technique DamID (DNA adenine methyltransferase identification) can be used for studies of DNA-protein interactions or chromatin profiling in plants DamID is a powerful method used to map the genomic interaction sites of these proteins in vivo It is based on fusing a protein of interest to Escherichia coli DNA adenine methyltransferase (dam). Expression of this fusion protein in vivo leads to preferential methylation of adenines in DNA surrounding the native binding sites of the dam fusion partner. Because adenine methylation does not occur endogenously in most eukaryotes, it provides a unique tag to mark protein interaction sites. DNA adenine methyltransferase identification (DamID) is an enzymatic technology for detecting DNA regions targeted by chromatin-associated proteins. Overall, DamID is highly robust: while the orientation of WT Dam fusions can affect the size of the target sets, their signatures remained largely reproducible. | A large variety of proteins bind to specific parts of the genome to regulate
gene expression, DNA replication, and chromatin structure. DamID is a powerful
method used to map the genomic interaction sites of these proteins in vivo. It
is based on fusing a protein of interest to Escherichia coli DNA adenine
methyltransferase (dam). Expression of this fusion protein in vivo leads to
preferential methylation of adenines in DNA surrounding the native binding sites
of the dam fusion partner. Because adenine methylation does not occur
endogenously in most eukaryotes, it provides a unique tag to mark protein
interaction sites. The adenine-methylated DNA fragments are isolated by
selective polymerase chain reaction amplification and can be identified by
microarray hybridization. We and others have successfully applied DamID to the
genome-wide identification of interaction sites of several transcription factors
and other chromatin-associated proteins. This chapter discusses DamID technology
in detail, and a step-by-step experimental protocol is provided for use in
Drosophila cell lines. We show here that the in vivo methylation-based tagging technique DamID (DNA
adenine methyltransferase identification) can be used for studies of DNA-protein
interactions or chromatin profiling in plants. We have demonstrated the
feasibility, reproducibility and sensitivity of the method in Arabidopsis
thaliana, using the well-known yeast GAL4 transcription factor, for which
DNA-binding sites (UAS(G)) were introduced into the plant genome. We monitored
the methylation resulting from the activity of DNA adenine methyltransferase
fused to the protein of interest, by combining digestion with
methylation-sensitive restriction enzymes and quantitative PCR. We then used
DamID to identify genomic targets of LHP1, a protein mostly associated with
euchromatin. We showed that LHP1 was targeted to the promoter and transcribed
regions of four genes: AG, AP3, FT and PI. Our data also demonstrate that LHP1,
like its animal homologues, has a high binding affinity for A/T-rich regions,
binding particularly strongly to the large regulatory introns of AG and PI. We
identified three major characteristics of LHP1 binding, highlighting the
similarities between plant LHP1 and animal HP1 proteins. The interaction of proteins with chromatin is fundamental for several essential
cellular processes. During the development of an organism, genes must to be
tightly regulated both temporally and spatially. This is achieved through the
action of chromatin-binding proteins such as transcription factors, histone
modifiers, nucleosome remodelers, and lamins. Furthermore, protein-DNA
interactions are important in the adult, where their perturbation can lead to
disruption of homeostasis, metabolic dysregulation, and diseases such as cancer.
Understanding the nature of these interactions is of paramount importance in
almost all areas of molecular biological research. In recent years, DNA adenine
methyltransferase identification (DamID) has emerged as one of the most
comprehensive and versatile methods available for profiling protein-DNA
interactions on a genomic scale. DamID has been used to map a variety of
chromatin-binding proteins in several model organisms and has the potential for
continued adaptation and application in the field of genomic biology. WIREs Dev
Biol 2016, 5:25-37. doi: 10.1002/wdev.205 For further resources related to this
article, please visit the WIREs website. Author information:
(1)Victor Chang Cardiac Research Institute, Darlinghurst, NSW 2010, Australia;
Australian Regenerative Medicine Institute, Monash University, Clayton, VIC
3800, Australia; Systems Biology Institute, Australia.
(2)Victor Chang Cardiac Research Institute, Darlinghurst, NSW 2010, Australia;
Children's Medical Research Institute, University of Sydney, 214 Hawkesbury
Road, Westmead, NSW 2145, Australia.
(3)Garvan Institute of Medical Research, Darlinghurst, NSW 2010, Australia; St.
Vincent's Clinical School, University of New South Wales, Kensington 2052,
Australia.
(4)Victor Chang Cardiac Research Institute, Darlinghurst, NSW 2010, Australia.
(5)Victor Chang Cardiac Research Institute, Darlinghurst, NSW 2010, Australia;
St. Vincent's Clinical School, University of New South Wales, Kensington 2052,
Australia. Electronic address: [email protected].
(6)Victor Chang Cardiac Research Institute, Darlinghurst, NSW 2010, Australia;
St. Vincent's Clinical School, University of New South Wales, Kensington 2052,
Australia; School of Biotechnology and Biomolecular Sciences, University of New
South Wales, Kensington 2052, Australia. Electronic address:
[email protected]. |
What is the function of the Spt6 gene in yeast? | Spt6 is a highly conserved histone chaperone that interacts directly with both RNA polymerase II and histones to regulate gene expression. Spt6 is a highly conserved factor required for normal transcription and chromatin structure. Binding of elongation factor Spt6 to Iws1 provides an effective means for coupling eukaryotic mRNA synthesis, chromatin remodelling and mRNA export. Spt6 Is Essential for rRNA Synthesis by RNA Polymerase I. Spt6 (suppressor of Ty6) has many roles in transcription initiation and elongation by RNA polymerase (Pol) II. We identify the histone H3-H4 chaperone Spt6 as the factor that mediates nucleosome reassembly onto the PHO5, PHO8, ADH2, ADY2, and SUC2 promoters during transcriptional repression. | The SPT4, SPT5 and SPT6 genes of Saccharomyces cerevisiae were identified
originally by mutations that suppress delta insertion mutations at HIS4 and
LYS2. Subsequent analysis has demonstrated that spt4, spt5 and spt6 mutations
confer similar pleiotropic phenotypes. They suppress delta insertion mutations
by altering transcription and are believed to be required for normal
transcription of several other loci. We have now analyzed interactions between
SPT4, SPT5 and SPT6. First, the combination of mutations in any two of these
three genes causes lethality in haploids. Second, some recessive mutations in
different members of this set fail to complement each other. Third, mutations in
all three genes alter transcription in similar ways. Finally, the results of
coimmunoprecipitation experiments demonstrate that at least the SPT5 and SPT6
proteins interact physically. Taken together, these genetic and biochemical
results indicate that SPT4, SPT5 and SPT6 function together in a transcriptional
process that is essential for viability in yeast. The SPT4, SPT5, and SPT6 gene products define a class of transcriptional
repressors in Saccharomyces cerevisiae that are thought to function through
their effects on chromatin assembly or stability. Mutations in these genes
confer a similar range of phenotypes to mutations in HIR genes, which encode
transcriptional repressors that regulate expression of many of the core histone
genes. Here we show that mutations in the three SPT genes also affect
transcription of the histone genes that reside at the HTA1-HTB1 locus. HTA1-lacZ
transcription was reduced in each spt mutant background, an effect that required
a negative site in the HTA1 promoter. The transcriptional effect could be
reversed by the overproduction of histones H2A and H2B in an spt4 mutant and
histones H3 and H4 in all three spt mutants. Suppression of the spt4
transcriptional defect was dependent on the overproduction of both histones H2A
and H2B, and required the presence of N-terminal amino acids in both histones.
The results are consistent with the idea that the effects of the spt mutations
on nucleosome assembly and/or stability activate repressors of HTA1
transcription. Previous characterization of the Saccharomyces cerevisiae Spt4, Spt5, and Spt6
proteins suggested that these proteins act as transcription factors that modify
chromatin structure. In this work, we report new genetic and biochemical studies
of Spt4, Spt5, and Spt6 that reveal a role for these factors in transcription
elongation. We have isolated conditional mutations in SPT5 that can be
suppressed in an allele-specific manner by mutations in the two largest subunits
of RNA polymerase II (Pol II). Strikingly, one of these RNA Pol II mutants is
defective for transcription elongation and the others cause phenotypes
consistent with an elongation defect. In addition, we show that spt4, spt5, and
spt6 mutants themselves have phenotypes suggesting defects in transcription
elongation in vivo. Consistent with these findings, we show that Spt5 is
physically associated with RNA Pol II in vivo, and have identified a region of
sequence similarity between Spt5 and NusG, an Escherichia coli transcription
elongation factor that binds directly to RNA polymerase. Finally, we show that
Spt4 and Spt5 are tightly associated in a complex that does not contain Spt6.
These results, taken together with the biochemical identification of a human
Spt4-Spt5 complex as a transcription elongation factor (Wada et al. 1998),
provide strong evidence that these factors are important for transcription
elongation in vivo. The packaging of the eukaryotic genome into chromatin is likely to have a
profound influence on transcription from the underlying genes. We have
previously shown that the disassembly of promoter nucleosomes is obligatory for
activation of the yeast PHO5 and PHO8 genes. Here, we show that the PHO5
promoter nucleosomes are reassembled concomitant with transcriptional repression
and displacement of the TATA binding protein and RNA polymerase II (RNA Pol II).
We identify the histone H3-H4 chaperone Spt6 as the factor that mediates
nucleosome reassembly onto the PHO5, PHO8, ADH2, ADY2, and SUC2 promoters during
transcriptional repression. Furthermore, promoter nucleosome reassembly is
essential for transcriptional repression. In the absence of Spt6-mediated
nucleosome reassembly, the activators Pho4 and Pho2 are displaced from the PHO5
promoter in repressing conditions, yet transcription is sustained. As such,
these studies demonstrate that activators are not required for transcription in
the absence of competing chromatin reassembly. Binding of elongation factor Spt6 to Iws1 provides an effective means for
coupling eukaryotic mRNA synthesis, chromatin remodelling and mRNA export. We
show that an N-terminal region of Spt6 (Spt6N) is responsible for interaction
with Iws1. The crystallographic structures of Encephalitozoon cuniculi Iws1 and
the Iws1/Spt6N complex reveal two conserved binding subdomains in Iws1. The
first subdomain (one HEAT repeat; HEAT subdomain) is a putative
phosphoprotein-binding site most likely involved in an Spt6-independent function
of Iws1. The second subdomain (two ARM repeats; ARM subdomain) specifically
recognizes a bipartite N-terminal region of Spt6. Mutations that alter this
region of Spt6 cause severe phenotypes in vivo. Importantly, the ARM subdomain
of Iws1 is conserved in several transcription factors, including TFIIS, Elongin
A and Med26. We show that the homologous region in yeast TFIIS enables this
factor to interact with SAGA and the Mediator subunits Spt8 and Med13,
suggesting the molecular basis for TFIIS recruitment at promoters. Taken
together, our results provide new structural information about the Iws1/Spt6
complex and reveal a novel interaction domain used for the formation of
transcription networks. CK2 is an essential protein kinase implicated in various cellular processes. In
this study, we address a potential role of this kinase in chromatin modulations
associated with transcription. We found that CK2 depletion from yeast cells
leads to replication-independent increase of histone H3K56 acetylation and
global activation of H3 turnover in coding regions. This suggests a positive
role of CK2 in maintece/recycling of the histone H3/H4 tetramers during
transcription. Interestingly, strand-specific RNA-seq analyses show that CK2
inhibits global cryptic promoters driving both sense and antisense
transcription. This further indicates a role of CK2 in the modulation of
chromatin during transcription. Next, we showed that CK2 interacts with the
major histone chaperone Spt6, and phosphorylates it in vivo and in vitro. CK2
phosphorylation of Spt6 is required for its cellular levels, for the suppression
of histone H3 turnover and for the inhibition of spurious transcription.
Finally, we showed that CK2 and Spt6 phosphorylation sites are important to
various transcriptional responses suggesting that cryptic intragenic and
antisense transcript production are associated with a defective adaptation to
environmental cues. Altogether, our data indicate that CK2 mediated
phosphorylation of Spt6 regulates chromatin dynamics associated with
transcription, and prevents aberrant transcription. |
What has pimavanserin been approved for by the FDA (2018)? | Pimavanserin was approved for the treatment of hallucinations and delusions associated with Parkinson's disease psychosis. | OBJECTIVE: To summarize the US Food and Drug Administration's (FDA's) review of
the safety and effectiveness for pimavanserin, an atypical antipsychotic, for
the treatment of hallucinations and delusions associated with Parkinson's
disease psychosis. We describe the regulatory and clinical issues important to
the FDA's approval of this New Drug Application, with special focus on the
risk-benefit balance. We also describe a new labeling feature that presents
additional efficacy data to clinicians.
DATA SOURCES: Data sets for all relevant clinical trials of pimavanserin and the
Applicant's and FDA's analyses of these data were considered in this review.
Data were available from 616 patients with Parkinson's disease with
hallucinations and delusions who received at least 1 dose of pimavanserin, with
a total exposure of 825 patient-years in the Parkinson's disease psychosis
population.
RESULTS: Pimavanserin 34 mg/d was effective in treating hallucinations and
delusions associated with Parkinson's disease. In the Applicant's single pivotal
trial, 80.5% of pimavanserin patients experienced at least some improvement in
symptoms compared to 58.1% of patients taking placebo. Pimavanserin did not
worsen motor function, an adverse effect commonly observed with other
antipsychotics, probably because of a lack of consequential dopamine binding.
CONCLUSIONS: Pimavanserin is the only FDA-approved treatment for the
hallucinations and delusions seen in patients with psychosis of Parkinson's
disease. Although pimavanserin appears to have a pharmacologic mechanism that is
different from other atypical antipsychotics, concern remained that the
increased risk of death seen with antipsychotic use in elderly demented
patients, and described in all approved antipsychotic labels, would also occur
with pimavanserin. Pimavanserin bears the same boxed warning about the risk of
death associated with antipsychotic use in elderly patients with dementia. |
List the members of a network of noncoding regulatory RNAs that play a role in the mammalian brain | In mice, the long ncRNA Cyrano uses an extensively paired site to miR-7 to trigger destruction of this microRNA. Cyrano-directed miR-7 degradation is much more effective than previously described examples of target-directed microRNA degradation, which come primarily from studies of artificial and viral RNAs. By reducing miR-7 levels, Cyrano prevents repression of miR-7-targeted mRNAs and enables accumulation of Cdr1as, a circular RNA known to regulate neuronal activity. Without Cyrano, excess miR-7 causes cytoplasmic destruction of Cdr1as in neurons, in part through enhanced slicing of Cdr1as by a second miRNA, miR-671. Thus, several types of ncRNAs can collaborate to establish a sophisticated regulatory network. | Noncoding RNAs (ncRNAs) play increasingly appreciated gene-regulatory roles.
Here, we describe a regulatory network centered on four ncRNAs-a long ncRNA, a
circular RNA, and two microRNAs-using gene editing in mice to probe the
molecular consequences of disrupting key components of this network. The long
ncRNA Cyrano uses an extensively paired site to miR-7 to trigger destruction of
this microRNA. Cyrano-directed miR-7 degradation is much more effective than
previously described examples of target-directed microRNA degradation, which
come primarily from studies of artificial and viral RNAs. By reducing miR-7
levels, Cyrano prevents repression of miR-7-targeted mRNAs and enables
accumulation of Cdr1as, a circular RNA known to regulate neuronal activity.
Without Cyrano, excess miR-7 causes cytoplasmic destruction of Cdr1as in
neurons, in part through enhanced slicing of Cdr1as by a second miRNA, miR-671.
Thus, several types of ncRNAs can collaborate to establish a sophisticated
regulatory network. |
Has ProSavin undergone phase IV clinical trials by 2018? | No, ProSavin has undergone a dose escalation, open-label, phase 1/2 trial. | BACKGROUND: Parkinson's disease is typically treated with oral dopamine
replacement therapies; however, long-term treatment leads to motor complications
and, occasionally, impulse control disorders caused by intermittent stimulation
of dopamine receptors and off-target effects, respectively. We aimed to assess
the safety, tolerability, and efficacy of bilateral, intrastriatal delivery of
ProSavin, a lentiviral vector-based gene therapy aimed at restoring local and
continuous dopamine production in patients with advanced Parkinson's disease.
METHODS: We undertook a phase 1/2 open-label trial with 12-month follow-up at
two study sites (France and UK) to assess the safety and efficacy of ProSavin
after bilateral injection into the putamen of patients with Parkinson's disease.
All patients were then enrolled in a separate open-label follow-up study of
long-term safety. Three doses were assessed in separate cohorts: low dose
(1·9×10(7) transducing units [TU]); mid dose (4·0×10(7) TU); and high dose
(1×10(8) TU). Inclusion criteria were age 48-65 years, disease duration 5 years
or longer, motor fluctuations, and 50% or higher motor response to oral
dopaminergic therapy. The primary endpoints of the phase 1/2 study were the
number and severity of adverse events associated with ProSavin and motor
responses as assessed with Unified Parkinson's Disease Rating Scale (UPDRS) part
III (off medication) scores, at 6 months after vector administration. Both
trials are registered at ClinicalTrials.gov, NCT00627588 and NCT01856439.
FINDINGS: 15 patients received ProSavin and were followed up (three at low dose,
six mid dose, six high dose). During the first 12 months of follow-up, 54
drug-related adverse events were reported (51 mild, three moderate). Most common
were increased on-medication dyskinesias (20 events, 11 patients) and on-off
phenomena (12 events, nine patients). No serious adverse events related to the
study drug or surgical procedure were reported. A significant improvement in
mean UPDRS part III motor scores off medication was recorded in all patients at
6 months (mean score 38 [SD 9] vs 26 [8], n=15, p=0·0001) and 12 months (38 vs
27 [8]; n=15, p=0·0001) compared with baseline.
INTERPRETATION: ProSavin was safe and well tolerated in patients with advanced
Parkinson's disease. Improvement in motor behaviour was observed in all
patients.
FUNDING: Oxford BioMedica. |
List approved radioprotective compounds | Only two radioprotective compounds, amifostine and palifermin, currently have the US FDA approval for use in radiation therapy. |