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Which de novo mutation in FGFR cause achondroplasia? | Recurrent missense mutations in a CpG doublet of the transmembrane domain of the FGFR3 protein (glycine substituted with arginine at residue 380, G380R). | Achondroplasia, the most common cause of chondrodysplasia in man (1 in 15,000
live births), is a condition of unknown origin characterized by short-limbed
dwarfism and macrocephaly. More than 90% of cases are sporadic and there is an
increased paternal age at the time of conception of affected individuals,
suggesting that de novo mutations are of paternal origin. Affected individuals
are fertile and achondroplasia is transmitted as a fully penetrant autosomal
domit trait, accounting for rare familial forms of the disease (10%). In
contrast, homozygous achondroplasia is usually lethal in the neonatal period and
affects 25% of the offspring of matings between heterozygous achondroplasia
parents. The gene responsible for achondroplasia has been mapped to chromosome
4p16.3 (refs 7, 8); the genetic interval encompassing the disease gene contains
a member of the fibroblast-growth-factor receptor (FGFR3) family which is
expressed in articular chondrocytes. Here we report the finding of recurrent
missense mutations in a CpG doublet of the transmembrane domain of the FGFR3
protein (glycine substituted with arginine at residue 380, G380R) in 17 sporadic
cases and 6 unrelated familial forms of achondroplasia. We show that the mutant
genotype segregates with the disease in these families. Thus it appears that
recurrent mutations of a single amino acid in the transmembrane domain of the
FGFR3 protein account for all cases (23/23) of achondroplasia in our series. |
List types of DNA lesions caused by UV light. | cyclobutane pyrimidine dimers
pyrimidine pyrimidone photoproducts
8-oxo-7,8-dihydroguanine | Xeroderma pigmentosum (XP), trichothiodystrophy (TTD) and Cockayne syndrome (CS)
are rare genetic diseases characterized by a large range of clinical symptoms.
However, they are all associated with defects in nucleotide excision repair
(NER), the system responsible for removing bulky DNA lesions such as those
generated by UV light: cyclobutane pyrimidine dimers (CPDs) and
pyrimidine-pyrimidone photoproducts (6-4 PPs). Over the past years, detailed
structural and biochemical information on NER-associated proteins has emerged.
In the first part of the article we briefly present the main steps of the NER
pathway with an emphasis on the precise role of certain proteins. Further, we
focus on clinical manifestations of the disorders and describe the diagnostic
procedures. Then we consider how current therapy and advanced technology could
improve patients' quality of life. Although to date the discussed diseases
remain incurable, effective sun protection, a well thought out diet, and
holistic medical care provide longer life and better health. This review
summarizes the current state of knowledge regarding the epidemiology of
NER-associated diseases, their genetic background, clinical features, and
treatment options. UV-induced DNA damage plays a key role in the initiation phase of skin cancer.
When left unrepaired or when damaged cells are not eliminated by apoptosis, DNA
lesions express their mutagneic properties, leading to the activation of
proto-oncogene or the inactivation of tumor suppression genes. The chemical
nature and the amount of DNA damage strongly depend on the wavelength of the
incident photons. The most energetic part of the solar spectrum at the Earth's
surface (UVB, 280-320 nm) leads to the formation of cyclobutane pyrimidine
dimers (CPDs) and pyrimidine (6-4) pyrimidone photoproducts (64PPs). Less
energetic but 20-times more intense UVA (320-400 nm) also induces the formation
of CPDs together with a wide variety of oxidatively generated lesions such as
single strand breaks and oxidized bases. Among those, 8-oxo-7,8-dihydroguanine
(8-oxoGua) is the most frequent since it can be produced by several mechanisms.
Data available on the respective yield of DNA photoproducts in cells and skin
show that exposure to sunlight mostly induces pyrimidine dimers, which explains
the mutational signature found in skin tumors, with lower amounts of 8-oxoGua
and strand breaks. The present review aims at describing the basic
photochemistry of DNA and discussing the quantitative formation of the different
UV-induced DNA lesions reported in the literature. Additional information on
mutagenesis, repair and photoprotection is briefly provided. Photolyases (PHRs) and cryptochromes (CRYs) belong to the same family known as
blue-light photoreceptors. Although their amino acid sequences and corresponding
structures are similar to each other, they exert different functions. PHRs
function as an enzyme to repair UV-induced deoxyribonucleic acid (DNA) lesions
such as a cyclobutane pyrimidine dimer (CPD) and a (6-4) photoproduct ((6-4)pp),
whereas CRYs are a circadian photoreceptor in plants and animals and at the same
time they control the photoperiodic induction of flowering in plants. When a new
type cryptochrome was identified, it was assumed that another type of CRYs,
cryptochrome-DASH (CRY-DASH), which is categorized as a subfamily of
photolyase/cryptochrome family, would possess the DNA photolyase activity.
However, CRY-DASH had a weak DNA photolyase activity, but the reason for this is
still unclear. To clarify the reason, we performed molecular dynamics (MD)
simulations for a complex of CPD-PHR or CRY-DASH with damaged double-stranded
DNA (dsDNA) and estimated the binding free energy, ΔGbind, between the protein
and the damaged dsDNA by using a molecular mechanics/Poisson-Boltzmann surface
area (MM/PBSA) method. ΔGbind for both proteins were -35 and 57 kcal mol-1,
respectively, indicating that the structural stability of CRY-DASH was lower
than that of CPD-PHR upon the damaged dsDNA binding. In particular, the number
of amino acid residues relevant to the damaged dsDNA binding on the CRY-DASH
surface was smaller than that on CPD-PHR. Therefore, the present result suggests
that CRY-DASH has a weak DNA photolyase activity because it has a lower binding
affinity than CPD-PHR. |
Has istadefylline been considered as a treatment for Parkinson's disease? | Yes, istradefylline is a new drug developed for the treatment of Parkinson's disease. | Istradefylline (ISD) is a new drug developed for the treatment of Parkinson's
disease (PD). It is an adenosine receptor A2A antagonists that will represent an
important option for patients with advanced PD where it has been demonstrated
efficacy in decreasing daily OFF time and is well tolerated. ISD has been
marketed in Japan since May 2013. Areas covered: The objective of this review is
to summarize evidences emerged from clinical studies that have demonstrated the
efficacy of ISD in advanced parkinsonian patients. It will then focus on the
potential role in treating non-motor symptoms (NMS) and cognitive decline, which
heavily affect quality of life for PD patients. Its putative role as
neuroprotective agent will also be discussed. Expert opinion: ISD might
represent an alternative option for patients with advanced PD. The reduction of
OFF time highlighted in pivotal trials is comparable to that obtained with
different levodopa adjunct therapies. The low profile of side effects makes ISD
a more suitable drug for advanced patients whose illness is complicated by
depression or cognitive impairment. Future studies are warranted to investigate
the possible effects of this drug to delay the occurrence of dyskinesia and to
impact significantly on NMS. |
In which cellular compartment do stress granules localize? | cytoplasm | Mutations in the gene encoding Fused in Sarcoma (FUS) cause amyotrophic lateral
sclerosis (ALS), a fatal neurodegenerative disorder. FUS is a predomitly
nuclear DNA- and RNA-binding protein that is involved in RNA processing. Large
FUS-immunoreactive inclusions fill the perikaryon of surviving motor neurons of
ALS patients carrying mutations at post-mortem. This sequestration of FUS is
predicted to disrupt RNA processing and initiate neurodegeneration. Here, we
demonstrate that C-terminal ALS mutations disrupt the nuclear localizing signal
(NLS) of FUS resulting in cytoplasmic accumulation in transfected cells and
patient fibroblasts. FUS mislocalization is rescued by the addition of the
wild-type FUS NLS to mutant proteins. We also show that oxidative stress
recruits mutant FUS to cytoplasmic stress granules where it is able to bind and
sequester wild-type FUS. While FUS interacts with itself directly by
protein-protein interaction, the recruitment of FUS to stress granules and
interaction with PABP are RNA dependent. These findings support a two-hit
hypothesis, whereby cytoplasmic mislocalization of FUS protein, followed by
cellular stress, contributes to the formation of cytoplasmic aggregates that may
sequester FUS, disrupt RNA processing and initiate motor neuron degeneration. Our previous study found that the nuclear protein, 68-kDa Src-associated in
mitosis protein (Sam68), is translocated to the cytoplasm and forms punctate
pattern during enterovirus 71 (EV71) infection [Virus Research, 180 (2014),
1-11]. However, the exact function of this punctate pattern in cytoplasm during
EV71 infection remains unknown. In this study, we firstly have examined this
punctate pattern of Sam68 re-localization in the cytoplasm, and observed the
obvious recruitments of Sam68 to the EV71-induced stress granules (SGs). Sam68,
belongs to the KH domain family of RNA binding proteins (RBPs), was then
confirmed that its KH domain was essential for this recruitment. Nevertheless,
Knockdown of Sam68 expression using ShRNA had no effects on SGs assembly,
indicating that Sam68 is not a constitutive component of the SGs during EV71
infection. Lastly, we investigated the importance of microtubulin transport to
SGs aggregation, and revealed that microtubule depolymerization inhibited SGs
formation, suggesting that EV71-induced SGs move throughout the cytoplasm in a
microtubule-dependent manner. Taken together, these results illuminated that
EV71 infections can induce SGs formation, and Sam68, as a SGs component,
migrates alone with SGs dependent on intact microtubule upon the viral
infections. These findings may provide novel underlying mechanism for
delineating the role of SGs during EV71 infection. Rbfox RNA-binding proteins play important roles in the regulation of alternative
pre-mRNA splicing, but their role in other gene regulatory mechanisms is not
well understood. Here, we show that Rbfox2 is a novel constituent of cytoplasmic
stress granules, the translational silencing machinery assembled in response to
cellular stress. We also show that the RNA binding activity of the Rbfox family
protein is crucial for its localization into stress granules. To investigate the
role of Rbfox2 in stress granules we used RNA-immunoprecipitation sequencing to
identify cytoplasmic transcriptome-wide targets of Rbfox2. We report that a
subset of cell cycle-related genes including retinoblastoma 1 is the target of
Rbfox2 in cytoplasmic stress granules, and Rbfox2 regulates the retinoblastoma 1
mRNA and protein expression levels during and following stress exposure. Our
study proposes a novel function for Rbfox2 in cytoplasmic stress granules. BACKGROUND: Amyotrophic lateral sclerosis (ALS) shows a strong genetic basis,
with SOD1, FUS, TARDBP, and C9ORF72 being the genes most frequently involved.
This has allowed identification of asymptomatic mutation carriers, which may be
of help in understanding the molecular changes preceding disease onset.
OBJECTIVES: We studied the cellular expression of FUS protein and the effect of
heat-shock- and dithiothreitol-induced stress in fibroblasts from FUS P525L
mutation carriers, healthy controls, and patients with sporadic ALS.
METHODS: Western blots and immunocytochemistry were performed to study the
subcellular localization of FUS protein. Control and stressed cells were double
stained with FUS and the stress marker TIA-R.
RESULTS: Fibroblasts from healthy controls and sporadic ALS cases showed a
prominent nuclear FUS expression. In the 2 FUS P525L mutation carriers, instead,
most cells showed a protein localization in both nucleus and cytoplasm, or
exclusively in the cytoplasm. Stress prompted the formation of cytoplasmic
granules in all subjects and in sporadic ALS FUS mislocalization to the
cytoplasm. Cytoplasmic FUS was recruited into stress granules, which showed a
time-dependent decrease in all subjects. However, in the FUS P525L fibroblasts,
the granules persisted longer, and they were more numerous than those detected
in the cells from controls and sporadic ALS patients.
CONCLUSIONS: We show that in fibroblasts of FUS P525L mutation carriers, FUS
mislocalized to the cytoplasm where it redistributed into stress granules with
likely a dose effect, i.e. a higher number of cells with granules, which persist
longer, than in controls and ALS cases. These data represent an early molecular
change occurring before ALS onset, suggesting a transient preaggregative state. Stress granules are non-membranous structures that transiently form in the
cytoplasm during cellular stress, where they promote translational repression of
non-essential RNAs and modulate cell signaling by sequestering key signal
transduction proteins. These and other functions of stress granules facilitate
an adaptive cellular response to environmental adversity. A key component of
stress granules is the prion-related RNA-binding protein, T cell intracellular
antigen-1 (TIA-1). Here, we report that recombit TIA-1 undergoes rapid
multimerization and phase separation in the presence of divalent zinc, which can
be reversed by the zinc chelator, TPEN. Similarly, the formation and maintece
of TIA-1-positive stress granules in arsenite-treated cells are inhibited by
TPEN. In addition, Zn2+ is released in cells treated with arsenite, before
stress granule formation. These findings suggest that Zn2+ is a physiological
ligand of TIA-1, acting as a stress-inducible second messenger to promote
multimerization of TIA-1 and subsequent localization into stress granules. |
Which software are used for the detection of selective sweeps? | Four open-source software releases (SweeD, SweepFinder, SweepFinder2, and OmegaPlus) are able to detect selective sweeps accurately. RAiSD (Raised Accuracy in Sweep Detection), an open-source software implements a parameter-free detection mechanism that relies on multiple signatures of a selective sweep via the enumeration of SNP vectors. | The production performance of pigs has been significantly improved due to
long-term artificial selection, and the specific variation characterizations
(selection signatures) emerged from the selected genome regions. Different types
of breeds are subjected to different selection intensities and had different
selection signatures. Selective sweep analysis is one of major methods to detect
the selection signatures. In this study, based on the 60K BeadChip genotyping
data of both commercial Large White (n=45) and local Tongcheng pigs (n=45),
genetic differentiation coefficient Fst was applied to detect the selection
signatures. Using gPLINK software to set quality control standards, a total of
34 304 SNPs were selected for statistical analysis. Fst values between two
breeds were estimated with Genepop package and the average Fst value was 0.3209.
Setting Fst>0.7036 (1% of total number of Fst values) as selection threshold,
344 SNPs were obtained and SNP location annotation indicated that there were 79
candidate genes (Sus scrofa Build 9). Furthermore, network analysis was
performed using Ingenuity Pathway Analysis and the preliminary results suggested
that most genes were involved in growth, reproduction, and immune response, such
as NCOA6, ERBB4, RUNX2, and APOB genes. The findings from this study will
contribute to further identification of candidate genes and causal mutations
implying for meat production and disease resistance in pig. The advent of modern DNA sequencing technology is the driving force in obtaining
complete intra-specific genomes that can be used to detect loci that have been
subject to positive selection in the recent past. Based on selective sweep
theory, beneficial loci can be detected by examining the single nucleotide
polymorphism patterns in intraspecific genome alignments. In the last decade, a
plethora of algorithms for identifying selective sweeps have been developed.
However, the majority of these algorithms have not been designed for analyzing
whole-genome data. We present SweeD (Sweep Detector), an open-source tool for
the rapid detection of selective sweeps in whole genomes. It analyzes site
frequency spectra and represents a substantial extension of the widely used
SweepFinder program. The sequential version of SweeD is up to 22 times faster
than SweepFinder and, more importantly, is able to analyze thousands of
sequences. We also provide a parallel implementation of SweeD for multi-core
processors. Furthermore, we implemented a checkpointing mechanism that allows to
deploy SweeD on cluster systems with queue execution time restrictions, as well
as to resume long-running analyses after processor failures. In addition, the
user can specify various demographic models via the command-line to calculate
their theoretically expected site frequency spectra. Therefore, (in contrast to
SweepFinder) the neutral site frequencies can optionally be directly calculated
from a given demographic model. We show that an increase of sample size results
in more precise detection of positive selection. Thus, the ability to analyze
substantially larger sample sizes by using SweeD leads to more accurate sweep
detection. We validate SweeD via simulations and by scanning the first
chromosome from the 1000 human Genomes project for selective sweeps. We compare
SweeD results with results from a linkage-disequilibrium-based approach and
identify common outliers. BACKGROUND: Adaptive alleles may rise in frequency as a consequence of positive
selection, creating a pattern of decreased variation in the neighboring loci,
known as a selective sweep. When the region containing this pattern is compared
to another population with no history of selection, a rise in variance of allele
frequencies between populations is observed. One challenge presented by large
genome-wide datasets is the ability to differentiate between patterns that are
remts of natural selection from those expected to arise at random and/or as a
consequence of selectively neutral demographic forces acting in the population.
FINDINGS: SmileFinder is a simple program that looks for diversity and
divergence patterns consistent with selection sweeps by evaluating allele
frequencies in windows, including neighboring loci from two or more populations
of a diploid species against the genome-wide neutral expectation. The program
calculates the mean of heterozygosity and FST in a set of sliding windows of
incrementally increasing sizes, and then builds a resampled distribution (the
baseline) of random multi-locus sets matched to the sizes of sliding windows,
using an unrestricted sampling. Percentiles of the values in the sliding windows
are derived from the superimposed resampled distribution. The resampling can
easily be scaled from 1 K to 100 M; the higher the number, the more precise the
percentiles ascribed to the extreme observed values.
CONCLUSIONS: The output from SmileFinder can be used to plot percentile values
to look for population diversity and divergence patterns that may suggest past
actions of positive selection along chromosome maps, and to compare lists of
suspected candidate genes under random gene sets to test for the
overrepresentation of these patterns among gene categories. Both applications of
the algorithm have already been used in published studies. Here we present a
publicly available, open source program that will serve as a useful tool for
preliminary scans of selection using worldwide databases of human genetic
variation, as well as population datasets for many non-human species, from which
such data is rapidly emerging with the advent of new genotyping and sequencing
technologies. |
Which organs are primarily damaged in SLE? | The patients with SLE are mostly affected by renal, peripheral vascular, musculoskeletal and neurological damage. The skin and heart are also damaged very frequently. | OBJECTIVE: To determine the accumulated end organ damage and health status in
patients with SS and to compare with patients with SLE (with or without SS).
METHODS: Thirty-seven patients with primary SS were studied and compared with
120 patients with SLE and 21 patients with SLE and SS. The Medical Outcome
Survey Short Form 20 with an additional question for fatigue was used to assess
health status. The SLICC/ACR damage index with a supplementary oral section was
used to assess end organ damage. For statistical analysis, logistic regression
analysis, Fisher's exact test, and Kruskal-Wallis rank tests were applied.
RESULTS: Patients in all 3 groups had reduced quality of life with respect to
all aspects of functional status and well being. There was no difference between
the groups. In the primary SS group, the greatest damage was in the oral section
(62% of patients). The patients with SLE and SS had the greatest renal,
peripheral vascular, and musculoskeletal damage (24, 19, 38% of patients,
respectively) followed by the SLE group. Ocular damage was more common in the
primary SS group, but that was due to older age in this group. Maligcy was
most common in the primary SS group (11%). Other organ damage scores did not
differ between groups.
CONCLUSION: End organ damage is uncommon in primary SS (with the exception of
oral damage), but the degree of functional ability is as great as in SLE. Increased longevity of patients with systemic lupus erythematosus (SLE) leads to
chronic organ damage accrual, which reduces the possibility of further survival
improvement in patients with the disease. Observations from lupus centres
worldwide revealed that the prevalence of damage occurring in the cardiovascular
system in patients with SLE has increased over the past four decades. The
results of a meta-analysis involving over 70 observational studies demonstrated
that lupus-related organ damage involving the neuropsychiatric and renal systems
also remains a major factor that limits survival improvement in patients with
this disease. While efforts to halt acute lupus-related injury are continuing,
through early diagnosis and effective use of immunosuppressive agents, a
concomitant strategy to improve survival of patients with SLE would be early
detection and timely treatment of lupus-related organ damage with meticulous
monitoring. This Review discusses the pattern and trend of organ damage in
patients with SLE worldwide, the potential serological and genetic mechanisms of
organ damage, and the advances in research on potential tools for early
detection of lupus-related organ damage, such as functional brain imaging
techniques, measurement of endothelial function, identification of biomarkers
from body fluids, and development of risk calculation models. OBJECTIVE: To examine long-term organ damage and safety following treatment with
belimumab plus standard of care (SoC) in patients with systemic lupus
erythematosus (SLE).
METHODS: Pooled data were examined from two ongoing open-label studies that
enrolled patients who completed BLISS-52 or BLISS-76. Patients received
belimumab every four weeks plus SoC. SLICC Damage Index (SDI) values were
assessed every 48 weeks (study years) following belimumab initiation (baseline).
The primary endpoint was change in SDI from baseline at study years 5-6.
Incidences of adverse events (AEs) were reported for the entire study period.
RESULTS: The modified intent-to-treat (MITT) population comprised 998 patients.
At baseline, 940 (94.2%) were female, mean (SD) age was 38.7 (11.49) years, and
disease duration was 6.7 (6.24) years. The mean (SD) SELENA-SLEDAI and SDI
scores were 8.2 (4.18) and 0.7 (1.19), respectively; 411 (41.2%) patients had
organ damage (SDI = 1: 235 (23.5%); SDI ≥ 2: 176 (17.6%)) prior to belimumab. A
total of 427 (42.8%) patients withdrew overall; the most common reasons were
patient request (16.8%) and AEs (8.5%).The mean (SD) change in SDI was +0.2
(0.48) at study years 5-6 (n = 403); 343 (85.1%) patients had no change from
baseline in SDI score (SDI +1: 46 (11.4%), SDI +2: 13 (3.2%), SDI +3: 1 (0.2%)).
Of patients without organ damage at baseline, 211/241 (87.6%) had no change in
SDI and the mean change (SD) in SDI was +0.2 (0.44). Of patients with organ
damage at baseline, 132/162 (81.5%) had no change in SDI and the mean (SD)
change in SDI was +0.2 (0.53). The probability of not having a worsening in SDI
score was 0.88 (95% CI: 0.85, 0.91) and 0.75 (0.67, 0.81) in those without and
with baseline damage, respectively (post hoc analysis).Drug-related AEs were
reported for 433 (43.4%) patients; infections/infestations (282, 28.3%) and
gastrointestinal disorders (139, 13.9%) were the most common.
CONCLUSION: Patients with SLE treated with long-term belimumab plus SoC had a
low incidence of organ damage accrual and no unexpected AEs. High-risk patients
with pre-existing organ damage also had low accrual, suggesting a favorable
effect on future damage development. |
What is Amyand hernia? | An Amyand hernia is a rare disease where the appendix is found within an inguinal hernia sac, which may or may not contain other abdominal contents or pathologic inflammatory changes. | BACKGROUND: Amyand's hernia is an inguinal hernia containing vermiform appendix.
We report a case of this rare condition, diagnostic findings, and management
considerations. A short review and history of Amyand's hernia is presented as
well.
METHODS: A literature search from Medline was done, and the published articles
were reviewed. A case of Amyand's hernia, which was recently managed by the
authors, was studied and the data reviewed.
RESULTS: Diagnosis of the Amyand's hernia is usually made intraoperatively. The
majority of the existing literature recommends doing open or laparoscopic
appendectomy with open repair of the inguinal hernia, although some authors
advise mesh repair of the hernia if the appendix is normal.
CONCLUSION: Amyand's hernia can be a challenge for the surgeon. We recommend
laparoscopic appendectomy and open repair of the inguinal hernia without using
mesh. Appendix-containing inguinal hernias are known as Amyand hernias. Traditionally,
these hernias have been diagnosed at surgery but are increasingly diagnosed on
abdominal computed tomography scans. The classification of Amyand hernias
determines their subsequent surgical management; as such, it is important for
the radiologist to be familiar with the appearances of the subtypes of Amyand
hernias. The finding of the appendix inside an hernial sac is called "Amyand hernia": The
global incidence is 0.28 to 1%. Clinical manifestations are the presence of an
inflamed inguinal mass, tense, hypersensitivensible, with variable size,
non-reducible, and associated to abdominal pain, vomit and very rarely true
appendicitis manifestations. Surgical treatment depends on the case presentation
and the intraoperative findings. We present a case of a giant Amyand's hernia
successfully treated with surgery by performing the hernia repair with Bassini
technique and transherniotomy appendectomy. Publisher: INTRODUZIONE: l’ernia inguinale è uno dei piu’ comuni problemi
chirurgici e spesso pone difficoltà tecniche, anche per il chirurgo esperto.
L’ernia di Amyand è un’ernia inguinale all’interno del cui sacco è contenuta
l’appendice vermiforme. CASO CLINICO: un uomo di 77 anni giunge alla nostra
osservazione per la valutazione di un’ernia inguinale destra ricorrente. Durante
l’intervento abbiamo scoperto un raro tipo di ernia di Amyand. Seguendo le linee
guida abbiamo eseguito un’ernioplastica inguinale ‘tension-free’ con utilizzo di
protesi evitando l’appendicectomia. Il paziente è stato dimesso il primo giorno
post-operatorio e ricontrollato dopo 7 giorni in regime ambulatoriale.
DISCUSSIONE: descritta per la prima volta da Claudius Amyand (1660-1740), un
chirurgo emigrato in Inghilterra ma di origine francese, che eseguì con successo
la prima appendicectomia durante un intervento di ernioplastica su un piccolo
paziente di 11 anni nel 1735 all’ospedale di St George. L’incidenza dell’ernia
di Amyand è dell’1%. L’associazione con un quadro di appendicite è ancora più
rara, intorno alla 0,1%. Losanoff e Basson hanno proposto uno schema di
classificazione per determinare la gestione chirurgica dell’ernia di Amyand, a
seconda che ci si trovi di fronte ad un quadro di appendicite o meno. Nel primo
caso è indicata l’appendicectomia evitando l’utilizzo di materiale protesico per
la cura dell’ernia. The presence of an incarcerated vermiform appendix within a femoral hernia
defect, a De Garengeot hernia, is distinctly different than an inguinal hernia
containing the appendix, an Amyand hernia. The De Garengeot hernia is a rare
finding with few reported cases. We present a 35-year-old female with a painful
groin mass palpable below the inguinal ligament. An ultrasound of the groin
revealed a thin-walled fluid collection medial to the femoral vessels. No
additional imaging at the time was obtained. Intra-operatively, the patient was
found to have her distal appendix incarcerated within the transected hernia sac
thus altering the planned surgical procedure. We present a unique operative
approach for managing a De Garengeot hernia. |
What is the Lupus Severity Index (LSI)? | It is a simple systemic lupus erythematosus (SLE) severity index that requires knowledge of only American College of Rheumatology (ACR) criteria and subcriteria. | OBJECTIVE: To develop a simple systemic lupus erythematosus (SLE) severity index
that requires knowledge of only American College of Rheumatology (ACR) criteria
and subcriteria.
METHODS: This study used demographic, mortality and medical records data of 1915
patients with lupus from the Lupus Family Registry and Repository. The data were
randomly split (2:1 ratio) into independent training and validation sets. A
logistic regression with ridge penalty was used to model the probability of
being prescribed major immunosuppressive drugs-a surrogate indicator of lupus
severity. ACR criteria and subcriteria were used as predictor variables in this
model, and the resulting regression coefficient estimates obtained from the
training data were used as item weightings to construct the severity index.
RESULTS: The resulting index was tested on the independent validation dataset
and was found to have high predictive accuracy for immunosuppressive use and
early mortality. The index was also found to be strongly correlated with a
previously existing severity score for lupus. In addition, demographic factors
known to influence lupus severity (eg, age of onset, gender and ethnicity) all
showed robust associations with our severity index that were consistent with
observed clinical trends.
CONCLUSIONS: This new index can be easily computed using ACR criteria, which may
be among the most readily available data elements from patient medical records.
This tool may be useful in lupus research, especially large dataset analyses to
stratify patients by disease severity, an important prognostic indicator in SLE. |
Is amantadine ER the first approved treatment for akinesia? | No, extended-release amantadine (amantadine ER) is the first approved medication for the treatment of dyskinesia. | Levodopa is the most efficacious treatment for Parkinson's disease (PD).
Long-term treatment with levodopa is limited due to dyskinesia. Dyskinesia in PD
can be socially and functionally disabling. Extended-release amantadine
(amantadine ER) is the first approved medication for the treatment of
dyskinesia. When it is given at bedtime, it reaches plasma concentration
approximately twice the level achieved by amantadine immediate release.
Amantadine ER reduces the severity and duration of dyskinesia during the day,
reduces OFF time and increases ON time without troublesome dyskinesia. The most
common side effects are hallucination, dizziness, orthostatic hypotension and
pedal edema. This review discusses the safety and efficacy of amantadine ER in
dyskinesia in PD patients. |
Which disease is Dasatinib used to treat? | Patients with chronic myeloid leukemia | Patients with chronic myeloid leukemia, treated with imatinib, who have a
durable complete molecular response, might remain in complete molecular response
after stopping treatment. Previous reports of patients stopping treatment in
complete molecular response have included only patients with a good response to
imatinib. We describe 3 patients with stable complete molecular response on
dasatinib treatment following imatinib failure. Two of the 3 patients remain in
complete molecular response more than 12 months after stopping dasatinib. In
these 2 patients we used highly sensitive patient-specific BCR-ABL1 DNA PCR to
show that the leukemic clone remains detectable, as we have previously shown in
imatinib-treated patients. Dasatinib-associated immunological phenomena, such as
the emergence of clonal T-cell populations, were observed both in one patient
who relapsed and in one patient in remission. Our results suggest that the
characteristics of complete molecular response on dasatinib treatment may be
similar to that achieved with imatinib, at least in patients with adverse
disease features. Sclerotic chronic graft-versus-host disease (scGVHD) is a severe form of this
disease that resembles systemic sclerosis and has limited and disappointing
treatment options. Tyrosine kinase inhibitors (TKI) targeting up-regulated
profibrotic pathways, such as imatinib mesylate, have been proposed as a
potential therapeutic approach for patients with scGVHD. Dasatinib, a
second-generation TKI with a well-established safety and efficacy profile in
chronic myeloid leukemia patients, who are refractory or intolerant to imatinib,
has also shown potent antifibrotic effects. We present here the first direct
clinical evidence, from 3 patients treated in a small single-center series,
suggesting that dasatinib can be a therapeutic option for patients with severe
scGVHD resistant or intolerant to imatinib. All patients achieved partial
response, with improvement in scGHVD target organs severity, joint mobility,
lung impairment, and deep fibrotic lesions. This clinical response has remained
stable or continued to improve after a median of 22 months (20-25) on dasatinib
treatment, with very good tolerance. In addition, corticosteroids could be
discontinued or significantly reduced in all patients. This clinical evidence
suggests that dasatinib could be a safe and effective alternative for scGVHD
patients refractory to corticosteroids and resistant or intolerant to imatinib.
Based on these preliminary findings, and in order to address appropriate patient
selection, time of intervention, and choice of drug, future larger studies
should more formally establish the efficacy and safety of second-generation TKI
for the treatment of scGVHD. This study aimed to determine whether the multi-kinase inhibitor dasatinib would
provide an effective therapy for myeloproliferative diseases (MPDs) involving
c-Cbl mutations. These mutations, which occur in the RING finger and linker
domains, abolish the ability of c-Cbl to function as an E3 ubiquitin ligase and
downregulate activated protein tyrosine kinases. Here we analyzed the effects of
dasatinib in a c-Cbl RING finger mutant mouse that develops an MPD with a
phenotype similar to the human MPDs. The mice are characterized by enhanced
tyrosine kinase signaling resulting in an expansion of hematopoietic stem cells,
multipotent progenitors and cells within the myeloid lineage. Since c-Cbl is a
negative regulator of c-Kit and Src signaling we reasoned that dasatinib, which
targets these kinases, would be an effective therapy. Furthermore, two recent
studies showed dasatinib to be effective in inhibiting the in vitro growth of
cells from leukemia patients with c-Cbl RING finger and linker domain mutations.
Surprisingly we found that dasatinib did not provide an effective therapy for
c-Cbl RING finger mutant mice since it did not suppress any of the hematopoietic
lineages that promote MPD development. Thus we conclude that dasatinib may not
be an appropriate therapy for leukemia patients with c-Cbl mutations. We did
however find that dasatinib caused a marked reduction of pre-B cells and
immature B cells which correlated with a loss of Src activity. This study is
therefore the first to provide a detailed characterization of in vivo effects of
dasatinib in a hematopoietic disorder that is driven by protein tyrosine kinases
other than BCR-ABL. Imatinib has improved outcomes in patients with Philadelphia chromosome-positive
(Ph+) acute lymphoblastic leukemia (all). Minimal residual disease (mrd) is a
useful tool for predicting leukemia relapse. However, there is no consensus on
how to treat children with elevation of BCR-ABL transcripts but no evidence of
hematologic relapse during chemotherapy combined with imatinib. Here, we report
the case of a child with Ph+ all who had persistent elevation of mrd, but no
evidence of hematologic relapse while receiving imatinib plus intensive
chemotherapy. Dasatinib was substituted for imatinib because no suitable donor
for allogeneic hematopoietic stem-cell transplantation (hsct) was available.
Less-intensive chemotherapy with methotrexate and 6-mercaptopurine was
administered concomitantly. No serious adverse events were encountered. With
continuous dasatinib combined with chemotherapy, but no allogeneic hsct, our
patient reached complete molecular remission and has been in complete molecular
remission for more than 13 months. This report is the first about the long-term
use of dasatinib in patients with Ph+ all and mrd elevation but hematologic
remission during imatinib chemotherapy. In a similar situation, chemotherapy
combined with dasatinib instead of allogeneic hsct could be considered to avoid
hsct-related mortality and morbidity. Clinical trials are needed. BACKGROUND: The use of imatinib combined with chemotherapy has demonstrated
improved outcome in adults with Philadelphia chromosome-positive acute
lymphoblastic leukemia (Ph-positive ALL). However, a substantial proportion of
patients continue to die as a result of disease progression.
PATIENTS AND METHODS: We assessed the minimal residual disease (MRD)-based
effect and long-term outcome of first-line incorporation of dasatinib (100 mg
once daily) into chemotherapy alternatively for adults with Ph-positive ALL. The
primary end point was the major molecular response (MMR) rate by the end of the
second dasatinib cycle. Patients with a donor proceeded to allogeneic stem cell
transplantation (SCT) as early as possible. MRD monitoring was centrally
evaluated by real-time quantitative polymerase chain reaction (4.5-log
sensitivity) using bone marrow samples.
RESULTS: Fifty-one patients (median age, 46 years) were enrolled and treated
with this strategy. After the first dasatinib cycle, 50 patients (98.0%)
achieved complete remission (CR). By the end of the second dasatinib cycle, 46
(93.9%) of 49 assessable patients had persistent CR, and 38 (77.6%) had MMR
(32.7%) or undetectable MRD (44.9%). On the basis of the MRD kinetics by this
time point, the numbers of early-stable, late, and poor molecular responders
were 23 (46.9%), 15 (30.7%), and 11 (22.4%), respectively. Thirty-nine patients
(76.5%) underwent allogeneic SCT in CR1. After a median follow-up of 54 months,
the 4-year cumulative incidence of relapse and disease-free survival (DFS) rate
for all patients were 30.0% and 52.0%, respectively, and the corresponding
outcomes among those receiving allogeneic SCT in CR1 were 20.5% and 64.1%,
respectively. Poor molecular responders had a higher risk of relapse and DFS
than those of early-stable molecular responders.
CONCLUSION: This dasatinib-based protocol was effective for achieving a good
quality molecular response and durable DFS in adults with Ph-positive ALL.
TRIAL REGISTRATION: clinicaltrials.gov, NCT01004497. A recent study reported that treatment-free remission (TFR) of chronic myeloid
leukemia (CML) after dasatinib (Das) treatment was significantly associated with
natural killer (NK) cell proliferation in the peripheral blood. However,
biomarkers to predict lymphocytosis or successful TFR are not well
characterized. In order to clarify individual differences in NK cell responses
among patients treated with Das, we retrospectively analyzed the association
between polymorphisms in the natural killer group 2D receptor [NKG2D; also known
as killer cell lectin like receptor K1 (KLRK1)] gene and clinical outcomes in 31
patients treated with Das as first-line treatment for CML. Patients with the
NKG2D HNK1/HNK1 (high-cytotoxic activity-related allele on NKG2D hb-1) haplotype
achieved MR4.5 more quickly than those with other haplotypes [hazard ratio (HR)
4.39; 95% confidence interval (CI) 2.75-118.6; P = 0.004]. In addition, NK cells
with the NKG2D HNK1 allele exhibited enhanced phosphorylation of vav guanine
nucleotide exchange factor 1 (VAV1) at Tyr174. These data suggest that NKG2D
gene polymorphisms may represent candidate biomarkers for the prediction of TFR
following Das treatment. BACKGROUND: There are no effective treatments or validated clinical response
markers in systemic sclerosis (SSc). We assessed imaging biomarkers and
performed gene expression profiling in a single-arm open-label clinical trial of
tyrosine kinase inhibitor dasatinib in patients with SSc-associated interstitial
lung disease (SSc-ILD).
METHODS: Primary objectives were safety and pharmacokinetics. Secondary outcomes
included clinical assessments, quantitative high-resolution computed tomography
(HRCT) of the chest, serum biomarker assays and skin biopsy-based gene
expression subset assignments. Clinical response was defined as decrease of >5
or >20% from baseline in the modified Rod Skin Score (MRSS). Pulmonary
function was assessed at baseline and day 169.
RESULTS: Dasatinib was well-tolerated in 31 patients receiving drug for a median
of nine months. No significant changes in clinical assessments or serum
biomarkers were seen at six months. By quantitative HRCT, 65% of patients showed
no progression of lung fibrosis, and 39% showed no progression of total ILD.
Among 12 subjects with available baseline and post-treatment skin biopsies,
three were improvers and nine were non-improvers. Improvers mapped to the
fibroproliferative or normal-like subsets, while seven out of nine non-improvers
were in the inflammatory subset (p = 0.0455). Improvers showed stability in
forced vital capacity (FVC) and diffusing capacity for carbon monoxide (DLCO),
while both measures showed a decline in non-improvers (p = 0.1289 and p =
0.0195, respectively). Inflammatory gene expression subset was associated with
higher baseline HRCT score (p = 0.0556). Non-improvers showed significant
increase in lung fibrosis (p = 0.0313).
CONCLUSIONS: In patients with SSc-ILD dasatinib treatment was associated with
acceptable safety profile but no significant clinical efficacy. Patients in the
inflammatory gene expression subset showed increase in skin fibrosis, decreasing
pulmonary function and worsening lung fibrosis during the study. These findings
suggest that target tissue-specific gene expression analyses can help match
patients and therapeutic interventions in heterogeneous diseases such as SSc,
and quantitative HRCT is useful for assessing clinical outcomes.
TRIAL REGISTRATION: Clinicaltrials.gov NCT00764309. A 37-year-old woman was diagnosed with chronic phase chronic myeloid leukemia.
Nilotinib treatment was initiated; however, it had to be discontinued due to an
allergic reaction one month later, and dasatinib treatment was provided.
Although favorable response was obtained, she started complaining of shortness
of breath 7 months after initiating dasatinib treatment. Chest X-ray and
echocardiography indicated pulmonary congestion and hypertension. Further, she
was diagnosed with mixed connective tissue disease (MCTD) based on Raynaud
phenomenon, swollen fingers, sclerodactyly, pancytopenia, hypocomplementemia,
and positive anti-U1-RNP antibody. Consequently, dasatinib treatment was
discontinued, and she was administered prednisolone (1 mg/kg/day), which was
effective and successfully tapered with concomitant administration of
cyclophosphamide. This is the first case of MCTD that developed during dasatinib
treatment. However, because the present case was a young woman, the development
of MCTD could probably be attributed to autoimmune diatheses or it may be a
coincidence. However, the possibility of patients receiving dasatinib treatment
developing autoimmune diseases needs to be assessed. |
Is g-H2AX a marker for double strand breaks? | Yes,
The specific phosphorylation of histone H2AX on serine residue 139, described as g-H2AX, is an excellent indicator or marker of DNA double-strand breaks (DSBs). | Genomic deoxyribonucleic acid (DNA) is continuously being damaged by endogenous
processes such as metabolism or by exogenous events such as radiation. The
specific phosphorylation of histone H2AX on serine residue 139, described as
γ-H2AX, is an excellent indicator or marker of DNA double-strand breaks (DSBs).
The yield of γ-H2AX (foci) is shown to have some correlation with the dose of
radiation or other DSB-causing agents. However, there is some discrepancy in the
DNA DSB foci yield among imaging and other methods such as gel electrophoresis.
Super-resolution imaging techniques are now becoming widely used as essential
tools in biology and medicine, after a slow uptake of their development almost
two decades ago. Here we compare several super-resolution techniques used to
image and determine the amount and spatial distribution of γ-H2AX foci formation
after X-ray irradiation: stimulated emission depletion (STED), ground-state
depletion microscopy followed by individual molecule return (GSDIM), structured
illumination microscopy (SIM), as well as an improved confocal, Airyscan and
HyVolution 2. We show that by using these super-resolution imaging techniques
with as low as 30-nm resolution, each focus may be further resolved, thus
increasing the number of foci per radiation dose compared to standard
microscopy. Furthermore, the DNA repair proteins 53BP1 (after low-LET
irradiations) and Ku70/Ku80 (from laser microbeam irradiation) do not always
yield a significantly increased number of foci when imaged by the
super-resolution techniques, suggesting that γ-H2AX, 53PB1 and Ku70/80 repair
proteins do not fully co-localize on the units of higher order chromatin
structure. Acetaminophen (APAP) overdose is the leading cause of acute liver failure (ALF)
with limited treatment options. It is known that liver regeneration following
APAP-induced ALF is a deciding factor in the final outcome. Previous studies
from our laboratory using an incremental dose model involving a regenerating
(300 mg/kg, APAP300) and a nonregenerating (600 mg/kg, APAP600) dose of APAP in
mice have revealed several proregenerative pathways that regulate regeneration
after APAP overdose. Here we report that DNA damage and repair mechanisms
regulate initiation of liver regeneration following APAP overdose. Mice treated
with nonregenerating APAP600 dose showed prolonged expression of pH2AX, a marker
of the DNA double-strand break (DSB), compared with APAP300. In regenerating
APAP300 dose-treated mice, H2AX was rapidly dephosphorylated at Tyr142,
indicating timely DNA repair. Expression of several DNA repair proteins was
substantially lower with APAP600. Poly(ADP) ribose polymerase (PARP) activation,
involved in DNA repair, was significantly higher in the APAP300 group compared
to the APAP600 group. Activation of p53, the major cell cycle checkpoint
protein, was significantly higher with APAP600 as demonstrated by substantially
higher expression of its target genes. Taken together, these data show that
massive DNA DSB occurs in high-dose APAP toxicity, and lack of prompt DSB repair
after APAP overdose leads to prolonged growth arrest and proliferative
senescence, resulting in inhibited liver regeneration. |
Which algorithm has been developed for finding conserved non-coding elements (CNEs)? | CNEFinder is a tool for identifying CNEs between two given DNA sequences with user-defined criteria. | MOTIVATION: Conserved non-coding elements (CNEs) represent an enigmatic class of
genomic elements which, despite being extremely conserved across evolution, do
not encode for proteins. Their functions are still largely unknown. Thus, there
exists a need to systematically investigate their roles in genomes. Towards this
direction, identifying sets of CNEs in a wide range of organisms is an important
first step. Currently, there are no tools published in the literature for
systematically identifying CNEs in genomes.
RESULTS: We fill this gap by presenting CNEFinder; a tool for identifying CNEs
between two given DNA sequences with user-defined criteria. The results
presented here show the tool's ability of identifying CNEs accurately and
efficiently. CNEFinder is based on a k-mer technique for computing maximal exact
matches. The tool thus does not require or compute whole-genome alignments or
indexes, such as the suffix array or the Burrows Wheeler Transform (BWT), which
makes it flexible to use on a wide scale.
AVAILABILITY AND IMPLEMENTATION: Free software under the terms of the GNU GPL
(https://github.com/lorrainea/CNEFinder). |
What type of antagonist is istradefylline? | Istradefylline is a selective adenosine A2A receptor antagonist. | BACKGROUND: Istradefylline, a selective adenosine A2A receptor antagonist, has
been reported to improve daily "off time" and motor symptoms in patients with
Parkinson's disease (PD). However, the effect of istradefylline on sleep
problems has not been thoroughly investigated.
METHODS: We evaluated the effect of istradefylline on daytime sleepiness, sleep
disturbances, and motor symptoms in 22 PD patients who were affected by the
wearing off phenomenon in an open-label, 3-month study. Participants received
20-40mg/day istradefylline once daily (morning) over a 3-month period. The
Epworth Sleepiness Scale (ESS), PD sleep scale (PDSS)-2 and PD Questionnaire
(PDQ-8) were administered at baseline, 2weeks, 1month, 2months and 3months. At
baseline and 3months, patients were evaluated on the Movement Disorder Society
Revision of the Unified PD Rating Scale (MDS-UPDRS) parts III and IV.
RESULTS: Twenty-one patients (95.5%) completed the study. At 3months, MDS-UPDRS
part III (-5.3, p=0.0002) and part IV (-2.5, p=0.001) scores improved and off
time decreased significantly (-50.1min, p=0.0004). PDQ-8 scores were unchanged
at 3months. ESS scores decreased significantly at 2months and 3months (-2.4 and
-3.3, respectively, p<0.0001), but the total PDSS-2 scores did not change.
CONCLUSION: Istradefylline improved daytime sleepiness in PD patients, possibly
through its effect on enhancing alertness. In addition, the lack of significant
changes in the total PDSS-2 scores over the study period suggests istradefylline
had no negative impact on sleep. |
What are the advantages of liquid biopsy in NSCLC? | Liquid biopsy reflected spatial and temporal heterogeneity of the tumor under treatment pressure. | The discovery of alterations in the EGFR and ALK genes, amongst others, in NSCLC
has driven the development of targeted-drug therapy using selective tyrosine
kinase inhibitors (TKIs). To optimize the use of these TKIs, the discovery of
new biomarkers for early detection and disease progression is mandatory. These
plasma-isolated exosomes can be used as a non-invasive and repeatable way for
the detection and follow-up of these biomarkers. One ml of plasma from 12 NSCLC
patients, with different mutations and treatments (and 6 healthy donors as
controls), were used as exosome sources. After RNAse treatment, in order to
degrade circulating miRNAs, the exosomes were isolated with a commercial kit and
resuspended in specific buffers for further analysis. The exosomes were
characterized by western blotting for ALIX and TSG101 and by transmission
electron microscopy (TEM) analysis, the standard techniques to obtain
biochemical and dimensional data of these ovesicles. Total RNA extraction was
performed with a high yield commercial kit. Due to the limited miRNA-content in
exosomes, we decided to perform retro-transcription PCR using an individual
assay for each selected miRNA. A panel of miRNAs (30b, 30c, 103, 122, 195, 203,
221, 222), all correlated with NSCLC disease, were analyzed taking advantage of
the remarkable sensitivity and specificity of Real-Time PCR analysis;
mir-1228-3p was used as endogenous control and data were processed according to
the formula 2(-) (ΔΔct) (13). Control values were used as baseline and results
are shown in logarithmic scale. Author information:
(1)Marlene and Stewart Greenebaum Comprehensive Cancer Center, University of
Maryland School of Medicine, Baltimore, Maryland.
(2)University of California Davis Comprehensive Cancer Center, Sacramento,
California.
(3)University of Turin, Department of Oncology at San Luigi Hospital, Orbassano,
Italy.
(4)Department of Thoracic Oncology, The Netherlands Cancer Institute and
Department of Pulmonary Disease, Academic Medical Center, Amsterdam, The
Netherlands.
(5)Multidisciplinary Oncology and Therapeutic Innovations Department, Assistance
Publique Hôpitaux de Marseille, Aix Marseille University, Marseille, France.
(6)Department of Medicine, Division of Hematology/Oncology, University of
California San Francisco, San Francisco, California.
(7)Yale Cancer Center, New Haven, Connecticut.
(8)State Key Laboratory of South China, Hong Kong Cancer Institute, The Chinese
University of Hong Kong, Hong Kong, China.
(9)Institute of Oncology, Soroka Medical Center and Ben Gurion University, Beer
Sheva, Israel.
(10)Department of Medicine I, Medical University of Vienna, Vienna, Austria.
(11)Memorial Cancer Institute, Memorial Healthcare System/Florida International
University (FIU) Miami, Florida.
(12)Department of Thoracic Oncology, Lung Clinic Grosshansdorf, Airway Research
Center North (ARCN), German Center for Lung Research (DZL), Grosshansdorf,
Germany.
(13)Massachusetts General Hospital Cancer Center and Harvard Medical School,
Boston, Massachusetts.
(14)University Health Network and Princess Margaret Cancer Centre, Toronto,
Ontario, Canada.
(15)Brigham and Women's Hospital and Department of Pathology, Harvard Medical
School, Boston, Massachusetts.
(16)National Cancer Centre Singapore and Genome Institute of Singapore,
Singapore.
(17)Department of Medicine, Division of Oncology, Stanford University School of
Medicine, Stanford, California.
(18)Department of Translational Molecular Pathology, The University of Texas MD
Anderson Cancer Center, Houston, Texas.
(19)International Association for the Study of Lung Cancer, Aurora, Colorado.
(20)Division of Medical Oncology, Department of Internal Medicine, The Ohio
State University, Columbus, Ohio.
(21)Division of Medical Oncology, Department of Medicine, University of Colorado
Anschutz Medical Campus, Aurora, Colorado, and the International Association for
the Study of Lung Cancer, Aurora, Colorado. Electronic address:
[email protected]. In non-small cell lung cancer (NSCLC), there is a consensus regarding the use of
liquid biopsy, generally, to detect "druggable" mutations and, in particular, to
monitor tyrosine kinase inhibitor (TKI) treatments. However, whether circulating
tumor cells (CTCs) are better tools than cell-free DNA (cfDNA), is still a
matter of debate, mainly concerning which antigen(s) we should use to
investigating simultaneously both epithelial and epithelial-to-mesenchymal
transient (EMT) phenotype in the same sample of CTCs. To address this item, we
exploited here a single-tube liquid biopsy, to detect both epithelial cell
adhesion molecule (EpCAM)-positive CTCs and EpCAM-low/negative CTCs, because
down-modulation of EpCAM is considered the first step in EMT. Furthermore, we
analyzed the DNA from CTCs of four different phenotypes (ctcDNA), according to
their EpCAM expression and cytokeratin pattern, and circulating tumor DNA
(ctDNA) by droplet digital PCR (ddPCR), in order to disclose activating and
resistance-driving mutations. Liquid biopsy reflected spatial and temporal
heterogeneity of the tumor under treatment pressure. We provide the
proof-of-concept that the complementary use of ctDNA and ctcDNA represents a
reliable, minimally invasive and dynamic tool for a more comprehensive view of
tumor evolution. |
What is the 4D-CHAINS algorithm? | The 4D-CHAINS/autoNOE-Rosetta is a complete pipeline for NOE-driven structure determination of medium- to larger-sized proteins. The 4D-CHAINS algorithm analyzes two 4D spectra recorded using a single, fully protonated protein sample in an iterative ansatz where common NOEs between different spin systems supplement conventional through-bond connectivities to establish assignments of sidechain and backbone resonances at high levels of completeness and with a minimum error rate. The 4D-CHAINS assignments are then used to guide automated assignment of long-range NOEs and structure refinement in autoNOE-Rosetta. | Automated methods for NMR structure determination of proteins are continuously
becoming more robust. However, current methods addressing larger, more complex
targets rely on analyzing 6-10 complementary spectra, suggesting the need for
alternative approaches. Here, we describe 4D-CHAINS/autoNOE-Rosetta, a complete
pipeline for NOE-driven structure determination of medium- to larger-sized
proteins. The 4D-CHAINS algorithm analyzes two 4D spectra recorded using a
single, fully protonated protein sample in an iterative ansatz where common NOEs
between different spin systems supplement conventional through-bond
connectivities to establish assignments of sidechain and backbone resoces at
high levels of completeness and with a minimum error rate. The 4D-CHAINS
assignments are then used to guide automated assignment of long-range NOEs and
structure refinement in autoNOE-Rosetta. Our results on four targets ranging in
size from 15.5 to 27.3 kDa illustrate that the structures of proteins can be
determined accurately and in an unsupervised manner in a matter of days. |
Which disorders are caused by de novo mutations in ZSWIM6? | Mutations in the ZSWIM6 gene, which encodes the cellular iron exporter ZEB6, are the cause of de novo autosomal recessive acromelic frontonasal dysostosis and Leber's hereditary optic neuropathy and/or dystonia. | Author information:
(1)Department of Genome Sciences, University of Washington, Seattle, WA 98195,
USA.
(2)Center for Developmental Biology and Regenerative Medicine, Seattle
Children's Research Institute, Seattle, WA 98101, USA; Department of Pediatrics,
University of Washington, Seattle, WA 98195, USA; Craniofacial Center, Seattle
Children's Hospital, Seattle, WA 98105, USA.
(3)Craniofacial Center, Seattle Children's Hospital, Seattle, WA 98105, USA.
(4)Center for Developmental Biology and Regenerative Medicine, Seattle
Children's Research Institute, Seattle, WA 98101, USA.
(5)Department of Radiology, UW Medicine, Seattle, WA 98195, USA.
(6)Department of Biochemistry and Biophysics, University of California, San
Francisco, San Francisco, CA 94158, USA.
(7)Trialomics, Seattle, WA 98101, USA.
(8)Center for Developmental Biology and Regenerative Medicine, Seattle
Children's Research Institute, Seattle, WA 98101, USA; Department of Pediatrics,
University of Washington, Seattle, WA 98195, USA.
(9)Center for Developmental Biology and Regenerative Medicine, Seattle
Children's Research Institute, Seattle, WA 98101, USA; Department of Pediatrics,
University of Washington, Seattle, WA 98195, USA; Craniofacial Center, Seattle
Children's Hospital, Seattle, WA 98105, USA. Electronic address:
[email protected]. |
Describe ChromoTrace | Recent advances of super-resolution microscopy in principle enable the mapping of specific molecular features with nanometer precision inside cells. Combined with highly specific, sensitive and multiplexed fluorescence labeling of DNA sequences this opens up the possibility of mapping the 3D path of the genome sequence in situ. ChromoTrace is a computational methodology to reconstruct the sequence configuration of all human chromosomes in the nucleus from a super-resolution image of a set of fluorescent in situ probes hybridized to the genome in a cell. ChromoTrace uses suffix trees to assign a known linear ordering of in situ probes on the genome to an unknown set of 3D in-situ probe positions in the nucleus from super-resolved images using the known genomic probe spacing as a set of physical distance constraints between probes. The algorithm can assign the 3D positions of the majority of loci with high accuracy and reasonable sensitivity to specific genome sequences. | The 3D structure of chromatin plays a key role in genome function, including
gene expression, DNA replication, chromosome segregation, and DNA repair.
Furthermore the location of genomic loci within the nucleus, especially relative
to each other and nuclear structures such as the nuclear envelope and nuclear
bodies strongly correlates with aspects of function such as gene expression.
Therefore, determining the 3D position of the 6 billion DNA base pairs in each
of the 23 chromosomes inside the nucleus of a human cell is a central challenge
of biology. Recent advances of super-resolution microscopy in principle enable
the mapping of specific molecular features with ometer precision inside
cells. Combined with highly specific, sensitive and multiplexed fluorescence
labeling of DNA sequences this opens up the possibility of mapping the 3D path
of the genome sequence in situ. Here we develop computational methodologies to
reconstruct the sequence configuration of all human chromosomes in the nucleus
from a super-resolution image of a set of fluorescent in situ probes hybridized
to the genome in a cell. To test our approach, we develop a method for the
simulation of DNA in an idealized human nucleus. Our reconstruction method,
ChromoTrace, uses suffix trees to assign a known linear ordering of in situ
probes on the genome to an unknown set of 3D in-situ probe positions in the
nucleus from super-resolved images using the known genomic probe spacing as a
set of physical distance constraints between probes. We find that ChromoTrace
can assign the 3D positions of the majority of loci with high accuracy and
reasonable sensitivity to specific genome sequences. By simulating appropriate
spatial resolution, label multiplexing and noise scenarios we assess our
algorithms performance. Our study shows that it is feasible to achieve
genome-wide reconstruction of the 3D DNA path based on super-resolution
microscopy images. |
What is the aim of iodine prophylaxis? | Due to high volatility and environmental mobility, radioactive isotopes of iodine pose a serious risk in the acute phases of a nuclear accident. The critical organ for iodine is the thyroid. A number of studies dealing with thyroid protection from exposure to radioiodine have shown that radioiodine uptake by the thyroid can be effectively blocked by administration of stable iodine, usually in the form of potassium iodide (KI) pills. | Due to high volatility and environmental mobility, radioactive isotopes of
iodine pose a serious risk in the acute phases of a nuclear accident. The
critical organ for iodine is the thyroid. A number of studies dealing with
thyroid protection from exposure to radioiodine have shown that radioiodine
uptake by the thyroid can be effectively blocked by administration of stable
iodine, usually in the form of potassium iodide (KI) pills. However, unless
perfectly timed, this protective action may be counterproductive. The
International Atomic Energy Agency recommends potassium iodide prophylaxis in
cases when an avertable thyroid dose by protective action exceeds 100 mGy. This
paper reviews experiences and practices with potassium iodide in the thyroid
protection. This kind of information should serve as the basis for discussion
and decision making on KI prophylactic programmes in nuclear emergency
situations in Croatia. If Croatia adopts such programme, it will still have to
develop the most effective way of KI stockpiling and distribution or
predistribution. Radioactive iodine isotopes may be released to air to a varying degree during
accidents with nuclear reactors. Iodine tablets, taken before or shortly after
such release, protect against intake of radioactive iodine isotopes, but not
against other radionuclides. Iodine prophylaxis can be a relevant countermeasure
in Norway and will be implemented according to recommendations from the Crisis
Committee for Nuclear and Radiological Emergencies. The Chernobyl accident
confirmed that the risk for radiogenic thyroid cancer is much higher for
foetuses and children and adolescents under 18 years. An epidemiological study
showed that intake of iodine tablets could reduce the risk for thyroid cancer by
a factor of three. For children, the WHO has therefore recommended a 10 mGy
avertable dose to the thyroid. The Norwegian Radiation Protection Authority
acknowledge the WHO guidelines and advise that the first priority of all
emergency preparedness planning for potential releases that can cause dispersion
of radioactive iodine, should be given to the protection of pregt and
breast-feeding women, newborns and children under 18 years. Iodine tablets
should be taken immediately (preferably not later than a few hours) in
situations where inhalation of radioactive iodine may occur. It should be
underlined that iodine prophylaxis is one of several emergency countermeasures;
other measures are sheltering and evacuation. The latter two countermeasures
will protect not only from intake of radioactive iodine, but also against other
radionuclides that may be released. Based on the present risk assessment in
Norway, iodine tablets have been distributed to the counties north of Salten. In
addition, there is an emergency stockpile of iodine tablets in Oslo. |
Through which molecular pathway does LB-100 reduce hepatic steatosis? | PP2A inhibition by LB100 significantly ameliorates hepatic steatosis by regulating hepatic lipogenesis and fatty acid oxidation via the AMPK/Sirt1 pathway. | |
Which drugs are included in PolyIran? | PolyIran polypill is composed of acetylsalicylic acid, hydrochlorothiazide, enalapril, and atorvastatin, whose efficacy in the treatment and prevention of cardiovascular disease has been documented in clinical trials. | BACKGROUND: The complexity of treatment regimens, costs and pill burden decrease
the medication adherence and contribute to shortfall in cardiovascular
preventive drug coverage. The polypill, a fixed dose combination pill of
established drugs, is expected to increase adherence and reduce the costs whilst
preventing major cardiovascular events (MCVE).
DESIGN AND METHODS: The PolyIran trial is a pragmatic cluster randomized trial
nested within the Golestan Cohort Study (GCS). Subjects were randomized to
either non-pharmacological preventive interventions alone (minimal care arm) or
together with a polypill (polypill arm) comprising hydrochlorothiazide, aspirin,
atorvastatin and either enalapril or valsartan. This study benefits from the
infrastructure of the primary health care system in Iran and the interventions
are delivered by the local auxiliary health workers (Behvarz) to the
participants. The primary outcome of the study is the occurrence of first MCVE
within five years defined as non-fatal and fatal myocardial infarction, unstable
angina, sudden death, heart failure, coronary artery revascularization
procedures, and non-fatal and fatal stroke.
TRIAL STATUS: From February 2011 to April 2013, 8410 individuals (236 clusters)
attended the eligibility assessment. Of those, 3421 in the polypill arm and 3417
in the minimal care arm were eligible. The study is ongoing.
CONCLUSION: The infrastructure of GCS and the primary health care system in Iran
enabled the conduct of this pragmatic large-scale trial. If the polypill
strategy proves effective, it may be implemented to prevent cardiovascular
disease in developing countries. BACKGROUND: Cardiovascular disease (CVD) is among the most common causes of
mortality in all populations. Nonalcoholic steatohepatitis is a common finding
in patients with CVD. Prevention of CVD in individual patients typically
requires periodic clinical evaluation, as well as diagnosis and management of
risk factors such as hypertension and hyperlipidemia. However, this is resource
consuming and hard to implement, especially in developing countries. We designed
a study to investigate the effects of a simpler strategy: a fixed-dose
combination pill consisting of aspirin, valsartan, atorvastatin and
hydrochlorthiazide (PolyPill) in an unselected group of persons aged over 50
years.
DESIGN: The PolyIran-Liver study was performed in Gonbad city as an open label
pragmatic randomized controlled trial nested within the Golestan Cohort Study.
We randomly selected 2,400 cohort study participants aged above 50 years,
randomly assigned them to intervention or usual care and invited them to
participate in an additional measurement study (if they met the eligibility
criteria) to measure liver related outcomes. Those agreeing and randomized to
the intervention arm were offered a daily single dose of PolyPill. We will
follow participants for 5 years. The primary outcome is major cardiovascular
events, secondary outcomes include all-cause mortality and liver related
outcomes: liver stiffness and liver enzyme levels. Cardiovascular outcomes and
mortality will be determined from the cohort study and liver-related outcomes in
those consenting to follow up. Analysis will be by allocated group.
TRIAL STATUS: Between October and December 2011, 1,320 intervention and 1,080
control participants were invited to participate in the additional measurement
study. For all these participants, the major cardiovascular events will be
determined using blind assessment of outcomes through the cohort study. In the
intervention and control arms, 875 (66%) and 721 (67%) respectively, met the
eligibility criteria and agreed to participate in the additional measurement
study. Liver related outcomes will be measured in these participants. Of the
1,320 participants randomized to the intervention, 787 (60%) accepted the
PolyPill.
CONCLUSION: The PolyIran-liver urban study will provide us with important
information on the effectiveness of PolyPill on major cardiovascular events,
all-cause mortality and liver related outcomes. (ClinicalTrials.gov ID:
NCT01245608). A new chromatographic-densitometric method has been developed for the
qualitative and quantitative determination of the active ingredients in a
simulated mixture corresponding to the PolyIran polypill, composed of
acetylsalicylic acid, hydrochlorothiazide (HCT), enalapril (ENA), and
atorvastatin (ATR), whose efficacy in the treatment and prevention of
cardiovascular disease has been documented in clinical trials. Chromatographic
separation was performed using TLC silica gel 60 plates with fluorescent
indicator F254 as the stationary phase and a mixture of n-hexane-ethyl
acetate-methanol-water-acetic acid (8.4 + 8 + 3 + 0.4 + 0.2, v/v/v/v/v) as the
mobile phase. Densitometric measurements were carried out at λ = 210 nm when
determining ENA and at λ = 265 nm in the case of the other drugs. Peaks of
examined substances were well separated in the recorded chromatograms, enabling
the evaluation of the results in terms of both qualitative and quantitative
analysis. The method was specific for the analyzed components and was
characterized by high sensitivity. The LOD was between 0.043 and 0.331 μg/spot,
and LOQ was between 0.100 and 0.942 μg/spot. Recovery was in the range of
97.02-101.34%. The linearity range was broad and ranged from 0.600 to 6.000
μg/spot for acetylsalicylic acid, from 0.058 to 1.102 μg/spot for HCT, from
0.505 to 6.560 μg/spot for ENA, and from 0.100 to 1.000 μg/spot for ATR. The
method was characterized by good precision, with RSD values that ranged from
0.10 to 2.26%. |
Are tumour specific antigens originating from known protein coding genes? | Heat-shock proteins (HSPs) function as ubiquitous tumour-specific antigens, with the specificity residing in a population of bound peptides that identify the tissue of origin of the HSP. Tumour antigens are mostly of weak immunogenicity, because the vast majority are tumour-associated differentiation antigens already 'seen' by the patient's immune system. | The identification of MHC-restricted and tumour-specific cytotoxic T lymphocytes
(CTLs) provides strong evidence in support of T cell-mediated immune
surveillance against human tumour cells. These CTLs recognize short peptides
derived from tumour-associated antigens in conjunction with class I molecules
expressed on tumour cells. In contrast to these observations there are now
numerous examples to suggest that a number of tumours escape this CTL-mediated
control either by down-regulating accessory molecules or by blocking the
intracellular processing of tumour-specific antigens. Recently a number of
tumour cell lines have been identified which display a transcriptional
deficiency of transporters associated with antigen processing (also referred to
as TAP). The Epstein-Barr virus (EBV)-associated tumour, Burkitt's lymphoma
(BL), is a classic example in this category. In the present study we have
restored class I-restricted antigen processing in a BL cell line by transfecting
a minigene expression vector encoding a CTL epitope derived from EBV linked to
an endoplasmic reticulum translocation signal sequence. These minigene
transfected BL cells were not only susceptible to lysis by virus-specific CTL
but were also capable of efficiently activating an antigen-specific CTL
response. Interestingly, the immunogenicity of these BL cells was not affected
by the significantly down-regulated expression of adhesion molecules such as
LFA1 alpha, LFA1 beta and LFA3. These findings suggest that resistance of tumour
cells to CTL-mediated immune control can be reversed if the relevant peptide
epitopes are appropriately presented on the cell surface. The concept of immunotherapy of cancer is more than a century old, but only
recently have molecularly defined therapeutic approaches been developed. In this
review, we focus on the most promising approach, active therapeutic vaccination.
The identification of tumour antigens can now be accelerated by methods allowing
the amplification of gene products selectively or preferentially transcribed in
the tumour. However, determining the potential immunogenicity of such gene
products remains a demanding task, since major histocompatibility complex (MHC)
restriction of T cells implies that for any newly defined antigen,
immunogenicity will have to be defined for any individual MHC haplotype.
Tumour-derived peptides eluted from MHC molecules of tumour tissue are also a
promising source of antigen. Tumour antigens are mostly of weak immunogenicity,
because the vast majority are tumour-associated differentiation antigens already
'seen' by the patient's immune system. Effective therapeutic vaccination will
thus require adjuvant support, possibly by new approaches to immunomodulation
such as bispecific antibodies or antibody-cytokine fusion proteins.
Tumour-specific antigens, which could be a more potent target for immunotherapy,
mostly arise by point mutations and have the disadvantage of being not only
tumour-specific, but also individual-specific. Therapeutic vaccination will
probably focus on defined antigens offered as protein, peptide or nucleic acid.
Irrespective of the form in which the antigen is applied, emphasis will be given
to the activation of dendritic cells as professional antigen presenters.
Dendritic cells may be loaded in vitro with antigen, or, alternatively,
initiation of an immune response may be approached in vivo by vaccination with
RNA or DNA, given as such or packed into attenuated bacteria. The importance of
activation of T helper cells has only recently been taken into account in cancer
vaccination. Activation of cytotoxic T cells is facilitated by the provision of
T helper cell-derived cytokines. T helper cell-dependent recruitment of elements
of non-adaptive defence, such as leucocytes, natural killer cells and monocytes,
is of particular importance when the tumour has lost MHC class I expression.
Barriers to successful therapeutic vaccination include: (i) the escape
mechanisms developed by tumour cells in response to immune attack; (ii)
tolerance or anergy of the evoked immune response; (iii) the theoretical
possibility of provoking an autoimmune reaction by vaccination against
tumour-associated antigens; and (iv) the advanced age of many patients, implying
reduced responsiveness of the senescent immune system. Early investigations into the immune surveillance of chemically-induced sarcomas
led to two important concepts in tumour immunobiology: one, tumour rejection can
be elicited by immune recognition of tumour antigens; and two, tumours express
unique sets of antigens, which are known as tumour-specific antigens. The
pioneering studies of Srivastava and colleagues led to the proposal that
heat-shock proteins (HSPs) function as ubiquitous tumour-specific antigens, with
the specificity residing in a population of bound peptides that identify the
tissue of origin of the HSP. However, recent findings, including new data on the
cell biology of peptide generation and trafficking, have called into question
the specificity of tumour rejection that is induced by HSPs. This review summarises the evolution of recent major advances in cancer
immunotherapy, using metastatic melanoma as a model. The first true clinical
progress with immunotherapy developed from the application of recombit DNA
technology for the large scale production of immunostimulant cytokines. Clinical
trials demonstrated that the systemic administration of recombit high-dose
bolus intravenous interleukin-2 (IL-2; 720 000 IU/kg every 8 hours) mediated
objective tumour progression in 20% of patients with metastatic renal cancer and
in 17% of patients with metastatic melanoma, with complete responses of 9% and
7%, respectively. The use of adoptive immunotherapy (the transfer of immune
cells with anti-tumour activity to the tumour-bearing host) focused interest on
T lymphocyte-mediated tumour recognition. Clinical trials described the systemic
administration of lymphokine activated killer (LAK) cells and subsequently
tumour infiltrating lymphocytes (TIL) to patients with advanced cancer. Although
able to kill tumour targets in vitro, LAK cells did not prove useful for the
treatment of patients with metastatic melanoma and renal cancer. A randomised
trial, in which IL-2 was administered alone or with LAK cells, failed to show a
difference in response rate or survival. In contrast, the treatment of 86
patients with metastatic melanoma using TIL plus IL-2 resulted in a 34%
objective response rate, which included patients who had previously failed
treatment with high-dose IL-2 alone. The focus on cellular immune responses,
combined with rapid biotechnological advances, resulted in the identification of
tumour specific antigens, such as MART-1 and gp100, that could be recognised by
autologous TIL. This provided fundamental evidence of the existence of
melanoma-associated antigens that were recognised in vivo by effector cells of
the immune system. In vitro studies demonstrated immunodomit epitopes from
MART-1 and gp100 that could induce in vitro-specific cytotoxic T lymphocyte
reactivity. To enhance in vitro immunogenicity, single amino acid substitutions
were made to identify peptides with higher affinity for HLA-A*0201. Modified
peptides from gp100 were compared with the parental peptide for increased
immunogenicity based on their ability to induce anti-tumour lymphocytes in
vitro. From these studies, a candidate peptide was identified (G9-209-2M) which
had increased immunogenic reactivity in vitro. Clinical trials demonstrated that
the modified G9-209-2M peptide was more effective. Unfortunately, objective
tumour regression was still low. However, when high-dose IL-2 was combined with
G9-209-2M objective clinical responses increased to 42%. Efforts to find better
ways to immunise against self antigens are ongoing and involve further peptide
immunisations, as well as recombit viral vectors, adjuvant cytokine therapy
and cellular adjuvants such as dendritic cells. The potential for cancer immunotherapy by adoptive transfer of CD4(+) T cells is
gaining increased attention. Most cancer cells lack major histocompatibility
complex (MHC) class II molecules and cannot present tumour-specific antigens
(TSA) directly to CD4(+) T cells. We have reported that tumour-specific CD4(+) T
cells collaborate with macrophages and dendritic cells. These professional
antigen-presenting cells endocytose and process TSA to display antigenic
peptides on their MHC class II molecules for indirect cancer cell recognition by
CD4(+) T cells. We hypothesized that this critical step may depend on secretion
of TSA by cancer cells. This was investigated in a mouse model for myeloma
immunosurveillance mediated by CD4(+) T cells. From this study, several
conclusions could be drawn. First, TSA secretion facilitates cancer
immunosurveillance. Second, TSA secretion results in stronger activation of
naïve tumour-specific CD4(+) T cells in lymph nodes. Third, TSA concentration
within the tumour extracellular matrix must reach a certain threshold to allow
successful cancer immunosurveillance. Fourth, treatment by local injection of
purified TSA enhances immunity against cancer cells that do not secrete TSA.
Fifth, secretion of TSA by at least some cancer cells within a tumour favours
antitumour immunity. Therefore, we propose that CD4(+) T cells that recognize
secreted TSA may be superior for immunotherapy by T cell transfer, because the
local extracellular antigen concentration will be higher for secreted TSA. Thus,
it is anticipated that secreted TSA will be more readily detected in vivo by
transferred CD4(+) T cells, resulting in more efficient tumour eradication. |
Mutations in which gene form the genetic basis of the DOORS syndrome? | Mutations in TBC1D24 seem to be an important cause of DOORS syndrome and can cause diverse phenotypes. Thus, individuals with DOORS syndrome without deafness and seizures but with the other features should still be screened for TBC1D24 mutations. More information is needed to understand the cellular roles of TBC1D24 and identify the genes responsible for DOORS phenotypes in individuals who do not have a mutation in TBC1D24. | Author information:
(1)Department of Molecular and Human Genetics, Baylor College of Medicine,
Houston, TX, USA.
(2)Department of Clinical and Experimental Epilepsy, UCL Institute of Neurology,
London, UK.
(3)Human Genome Sequencing Center, Baylor College of Medicine, Houston, TX, USA;
Department of Structural and Computational Biology and Molecular Biophysics,
Baylor College of Medicine, Houston, TX, USA.
(4)Department of Pharmacology, Baylor College of Medicine, Houston, TX, USA.
(5)Department of Pediatrics, Toyohashi Municipal Hospital, Toyohashi, Aichi,
Japan.
(6)Children's Hospital Central California, Madera, California, USA.
(7)Genetics Service, Belfast City Hospital, Belfast, Ireland.
(8)Medical Genetics Service, Clinical Hospital of Porto Alegre, Porto Alegre,
Brazil.
(9)Department of Medical Genetics, University Hospital Antwerp, 2650 Antwerp,
Belgium.
(10)Department of Medical Genetics, Poznañ University of Medical Sciences,
Poznañ, Poland.
(11)Medical Genetics Department, Istanbul Medical Faculty, Istanbul University,
Turkey.
(12)Department of Genetics, University of Groningen, Groningen, Netherlands.
(13)Department of Pediatric Genetics, Amrita Institute of Medical Sciences and
Research Centre, Kerala, India.
(14)Genetic Health Service New Zealand-Northern Hub, Auckland City Hospital,
Auckland, New Zealand.
(15)Pediatric Neurology, Braunschweig Hospital, Braunschweig, Germany.
(16)Department of Pediatrics, Saveetha Medical College and Hospital, Saveetha
University, Chennai, Tamil Nadu, 600077, India.
(17)Division of Genetics, Children's Mercy Hospitals and Clinics and the
University of Missouri-Kansas City School of Medicine, Kansas City, MO, USA.
(18)Department of Medical Genetics, Montreal Children's Hospital, McGill
University Health Center, Quebec, Canada.
(19)Department of Pediatrics, NKP Salve Institute of Medical Sciences and Lata
Mangeshkar Hospital, Maharashtra, India.
(20)University of Washington Medical Center, Seattle, WA, USA.
(21)Center for Human Genetics, Facultad de Medicina, Clínica Alemana-Universidad
del Desarrollo, Santiago, Chile.
(22)Department of Pediatrics, University of California San Francisco, San
Francisco, CA, USA.
(23)Department of Clinical Genetics, Churchill Hospital, Oxford, UK.
(24)Clinical Genetics Department, Great Ormond Street Hospital for Children NHS
Foundation Trust, London, UK.
(25)Centre Référence Anomalie Développement et Syndromes Malformatifs, Centre
Hospitalier Universitaire de Nice, France.
(26)Kariminejad-Najmabadi Pathology and Genetics Center, Tehran, Iran.
(27)Manchester Centre for Genomic Medicine, Institute of Human Development,
Faculty of Medical and Human Sciences, University of Manchester, Manchester, UK;
Manchester Centre for Genomic Centre for Genetic Medicine, Institute of Human
Development, Faculty of Medical and Human Sciences, University of Manchester,
Manchester, UK; St Mary's Hospital, Manchester Academic Health Science Centre,
Manchester, UK.
(28)Department of Medical Genetics, University Medical Center Utrecht, Utrecht,
Netherlands.
(29)Institut für Humangenetik, University of Duisburg-Essen, University Hospital
Essen, Essen, Germany.
(30)Department of Pediatrics and Translational Genetics, Academic Medical
Center, University of Amsterdam, Amsterdam, Netherlands.
(31)Human Genome Sequencing Center, Baylor College of Medicine, Houston, TX,
USA.
(32)Department of Molecular and Human Genetics, Baylor College of Medicine,
Houston, TX, USA; Howard Hughes Medical Institutes, Houston, TX, USA. Electronic
address: [email protected].
(33)Department of Clinical and Experimental Epilepsy, UCL Institute of
Neurology, London, UK; Epilepsy Society, Buckinghamshire, UK. Electronic
address: [email protected]. This issue of Seminars in Medical Genetics, American Journal of Medical Genetics
Part C investigates the human diseases caused by mutations in the BAF complex
(also known as the mammalian SWI/SNF complex) genes, particularly focusing on
Coffin-Siris syndrome (CSS). CSS is a rare congenital malformation syndrome
characterized by developmental delay or intellectual disability (ID), coarse
facial appearance, feeding difficulties, frequent infections, and
hypoplasia/aplasia of the fifth fingernails and fifth distal phalanges. In 2012,
42 years after the first description of CSS in 1970, five causative genes
(SMARCB1, SMARCE1, SMARCA4, ARID1A, ARID1B), all encoding components of the BAF
complex, were identified as being responsible for CSS through whole exome
sequencing and pathway-based genetic screening. The identification of two
additional causative genes (PHF6, SOX11) followed. Mutations in another BAF
complex gene (SMARCA2) and (TBC1D24) were found to cause clinically similar
conditions with ID, Nicolaides-Baraitser syndrome and DOORS syndrome,
respectively. Also, ADNP was found to be mutated in an autism/ID syndrome.
Furthermore, there is growing evidences for germline or somatic mutations in the
BAF complex genes to be causal for cancer/cancer predisposition syndromes. These
discoveries have highlighted the role of the BAF complex in the human
development and cancer formation. The biology of BAF is very complicated and
much remains unknown. Ongoing research is required to reveal the whole picture
of the BAF complex in human development, and will lead to the development of new
targeted therapies for related disorders in the future. Mutations in the Tre2/Bub2/Cdc16 (TBC)1 domain family member 24 (TBC1D24) gene
are associated with a range of inherited neurological disorders, from
drug-refractory lethal epileptic encephalopathy and DOORS syndrome (deafness,
onychodystrophy, osteodystrophy, mental retardation, seizures) to non-syndromic
hearing loss. TBC1D24 has been implicated in neuronal transmission and
maturation, although the molecular function of the gene and the cause of the
apparently complex disease spectrum remain unclear. Importantly, heterozygous
TBC1D24 mutation carriers have also been reported with seizures, suggesting that
haploinsufficiency for TBC1D24 is significant clinically. Here we have
systematically investigated an allelic series of disease-associated mutations in
neurons alongside a new mouse model to investigate the consequences of TBC1D24
haploinsufficiency to mammalian neurodevelopment and synaptic physiology. The
cellular studies reveal that disease-causing mutations that disrupt either of
the conserved protein domains in TBC1D24 are implicated in neuronal development
and survival and are likely acting as loss-of-function alleles. We then further
investigated TBC1D24 haploinsufficiency in vivo and demonstrate that TBC1D24 is
also crucial for normal presynaptic function: genetic disruption of Tbc1d24
expression in the mouse leads to an impairment of endocytosis and an enlarged
endosomal compartment in neurons with a decrease in spontaneous
neurotransmission. These data reveal the essential role for TBC1D24 at the
mammalian synapse and help to define common synaptic mechanisms that could
underlie the varied effects of TBC1D24 mutations in neurological disease. |
What is the aim of the "Radiogenomics Consortium"? | A major aim of research in radiogenomics is the development of a predictive instrument to enable identification of people who are at greatest risk for adverse effects resulting from cancer treatment using radiation. An important effort to advance radiobiology in the genomic era was establishment of the Radiogenomics Consortium to enable the creation of the large radiotherapy cohorts required to exploit advances in genomics. | Author information:
(1)Maastricht University Medical Center, Department of Radiation Oncology
(MAASTRO Clinic), The Netherlands; KU Leuven, Radiation Oncology, Belgium.
Electronic address: [email protected].
(2)KU Leuven, Radiation Oncology, Belgium.
(3)Department of Clinical Epidemiology and Medical Technology Assessment,
Maastricht University Medical Centre, The Netherlands.
(4)Maastricht University Medical Center, Department of Radiation Oncology
(MAASTRO Clinic), The Netherlands.
(5)Patient Advocate, Hasselt, Belgium.
(6)Patient Advocate, Cambridge, UK.
(7)Patient Advocate, Manchester, UK.
(8)University of Maryland, School of Medicine, USA.
(9)The University of Manchester, Manchester Academic Health Science Centre, UK.
(10)Department of Radiation Oncology and Medical Physics, Institut Regional du
Cancer Montpellier, France.
(11)University of Rochester Medical Center, USA.
(12)The University of Manchester, Translational Radiobiology Group I Institute
of Cancer Sciences, The Christie NHS Foundation Trust, UK. The overall goal of radiogenomics is the identification of genomic markers that
are predictive for the development of adverse effects resulting from cancer
treatment with radiation. The principal rationale for a focus on toxicity in
radiogenomics is that for many patients treated with radiation, especially
individuals diagnosed with early-stage cancers, the survival rates are high, and
therefore a substantial number of people will live for a significant period of
time beyond treatment. However, many of these patients could suffer from
debilitating complications resulting from radiotherapy. Work in radiogenomics
has greatly benefited from creation of the Radiogenomics Consortium (RGC) that
includes investigators at multiple institutions located in a variety of
countries. The common goal of the RGC membership is to share biospecimens and
data so as to achieve large-scale studies with increased statistical power to
enable identification of relevant genomic markers. A major aim of research in
radiogenomics is the development of a predictive instrument to enable
identification of people who are at greatest risk for adverse effects resulting
from cancer treatment using radiation. It is anticipated that creation of a
predictive assay characterized by a high level of sensitivity and specificity
will improve precision radiotherapy and assist patients and their physicians to
select the optimal treatment for each individual. Radiobiology research is building the foundation for applying genomics in
precision radiation oncology. Advances in high-throughput approaches will
underpin increased understanding of radiosensitivity and the development of
future predictive assays for clinical application. There is an established
contribution of genetics as a risk factor for radiotherapy side effects. An
individual's radiosensitivity is an inherited polygenic trait with an
architecture that includes rare mutations in a few genes that confer large
effects and common variants in many genes with small effects. Current thinking
is that some will be tissue specific, and future tests will be tailored to the
normal tissues at risk. The relationship between normal and tumor cell
radiosensitivity is poorly understood. Data are emerging suggesting interplay
between germline genetic variation and epigenetic modification with growing
evidence that changes in DNA methylation regulate the radiosensitivity of cancer
cells and histone acetyltransferase inhibitors have radiosensitizing effects.
Changes in histone methylation can also impair DNA damage response signaling and
alter radiosensitivity. An important effort to advance radiobiology in the
genomic era was establishment of the Radiogenomics Consortium to enable the
creation of the large radiotherapy cohorts required to exploit advances in
genomics. To address challenges in harmonizing data from multiple cohorts, the
consortium established the REQUITE project to collect standardized data and
genotyping for ~5,000 patients. The collection of detailed dosimetric data is
important to produce validated multivariable models. Continued efforts will
identify new genes that impact on radiosensitivity to generate new knowledge on
toxicity pathogenesis and tests to incorporate into the clinical decision-making
process. |
Who should wear dosimeters? | Nuclear medicine technologists rely on a single dosimeter to measure their work-related dose. Dosimetry for the study of medical radiation workers. | OBJECTIVE: Nuclear medicine technologists rely on a single dosimeter to measure
their work-related dose. Estimates of whole-body effective dose are based on the
assumptions that the radiation is incident from the front and in a uniform beam.
We sought to investigate these assumptions and also to quantify doses associated
with different activities.
METHODS: A single technologist wore 3 electronic dosimeters for 3 mo, at the
front waist, the back waist, and the front collar. The technologist also
recorded her activities throughout the day.
RESULTS: We found that the assumption of an anterior beam held about two thirds
of the time, breaking down only when the technologist was receiving lower doses.
Overall, the average whole-body dose was estimated correctly by assuming an
anterior beam. We also found that irradiation was uniform (i.e., waist and
collar badges gave equivalent readings) except when the technologist was
performing injections. Then, the collar readings were 1.7 times the waist
readings. Finally, average doses were measured for different types of
activities. Performing injections registered a dose rate of approximately 2
microSv/h. Doses received while scanning ranged from 0.2 to 2 microSv/h. The
average dose for a scan depended not only on the administered activity and
isotope but also on the amount of patient contact required. Even for high
activities, such as patients who had already received therapy, the dose to the
technologist was low for patients requiring little assistance.
CONCLUSION: The assumption of anterior irradiation correctly estimates
whole-body effective dose. The assumption of a uniform beam is good except when
injections are being performed, when the upper torso receives a much higher dose
than the waist. Overall, doses to the technologist were found to be 5.4
microSv/d for scanning and 12 microSv/d for injections. These correspond to 1.4
mSv/y and 3.2 mSv/y, respectively, which are comparable to naturally occurring
radiation levels and are much lower than regulatory limits. However, if the dose
to a particular technologist needs to be minimized (e.g., for a pregt
worker), the most effective strategy is for the technologist to be assigned
patients requiring little contact or assistance and, in particular, to avoid
administering injections. One of the main goals for Radiation Safety Professionals is to help maintain
radiation worker doses below administrative control levels. In the radiation
safety field there is an increasing recognition of the value of
dosimetry-related data that can be used to enhance safety programs and
regulatory compliance. Mining radiation dosimetry data and rendering results in
the form of dashboards provides insights for the Radiation Safety Professionals
that could help improve the radiological protection programs effectiveness,
enhances quality, and reduces cost. Quite often the professionals spend more
time assembling data than analyzing for trends and acting to improve the
radiation safety program. Data analysis tools were developed allowing the
radiation safety professionals to perform surveillance on key parameters in the
dosimetry program that can help identifying risks and insure early intervention.
More than 2,200 institutions chosen from different industries were surveyed for
more than 2 years after the implementation of this tool. Four indicators: dose
per participant, collective dose, dosimeter return compliance, and number of
workers exceeding ALARA levels were chosen as meaningful parameters in
characterizing the health of the program. These parameters were tracked,
analyzed, and compared to benchmarks developed based on more than 1 million
monitored workers. BACKGROUND: The reconstruction of lifetime radiation doses for medical workers
presents special challenges not commonly encountered for the other worker
cohorts comprising the Million Worker Study.
METHODS: The selection of approximately 175,000 medical radiation workers relies
on using estimates of lifetime and annual personal monitoring results collected
since 1977. Approaches have been created to adjust the monitoring results so
that mean organ absorbed doses can be estimated.
RESULTS: Changes in medical technology and practices have altered the radiation
exposure environments to which a worker may have been exposed during their
career. Other temporal factors include shifts in regulatory requirements that
influenced the conduct of radiation monitoring and the changes in the measured
dose quantities.
CONCLUSIONS: The use of leaded aprons during exposure to lower energy X rays
encountered in fluoroscopically based radiology adds complexity to account for
the shielding of the organs located in the torso when dosimeters were worn over
leaded aprons. Estimating doses to unshielded tissues such as the brain and lens
of the eye become less challenging when dosimeters are worn at the collar above
the apron. The absence of leaded aprons in the higher energy photon settings
lead to a more straightforward process of relating dosimeter results to mean
organ doses. |
What kind of molecule is AZD8601? | AZD8601 is a modified mRNA. | |
Which disease category is LB-100 mostly assessed for? | LB-100 is designed to sensitize cancer cells to DNA damage from irradiation and chemotherapy. It is assessed for its therapeutic potential against cancer. | The protein phosphatase 2A (PP2A) inhibitor, LB100, has been shown in
pre-clinical studies to be an effective chemo- and radio-sensitizer for
treatment of various cancers. We investigated effects associated with LB100
treatment alone and in combination with cisplatin for medulloblastoma (MB) in
vitro and in vivo in an intracranial xenograft model. We demonstrated that LB100
had a potent effect on MB cells. By itself, LB100 inhibited proliferation and
induced significant apoptosis in a range of pediatric MB cell lines. It also
attenuated MB cell migration, a pre-requirement for invasion. When used in
combination, LB100 enhanced cisplatin-mediated cytotoxic effects. Cell viability
in the presence of 1 uM cisplatin alone was 61% (DAOY), 100% (D341), and 58%
(D283), but decreased with the addition of 2 μM of LB100 to 26% (DAOY), 67%
(D341), and 27% (D283), (p < 0.005). LB100 suppressed phosphorylation of the
STAT3 protein and several STAT3 downstream targets. Also, LB100 directly
increased cisplatin uptake and overcame cisplatin-resistance in vitro. Finally,
LB100 exhibited potent in vivo anti-neoplastic activity in combination with
cisplatin in an intracranial xenograft model. BACKGROUND: Standard therapy for chordoma consists of surgical resection
followed by high-dose irradiation. Protein phosphatase 2A (PP2A) is a
ubiquitously expressed serine/threonine phosphatase involved in signal
transduction, cell cycle progression, cell differentiation, and DNA repair.
LB100 is a small-molecule inhibitor of PP2A designed to sensitize cancer cells
to DNA damage from irradiation and chemotherapy. A recently completed phase I
trial of LB100 in solid tumors demonstrated its safety. Here, we show the
therapeutic potential of LB100 in chordoma.
METHODS: Three patient-derived chordoma cell lines were used: U-CH1, JHC7, and
UM-Chor1. Cell proliferation was determined with LB100 alone and in combination
with irradiation. Cell cycle progression was assessed by flow cytometry.
Quantitative γ-H2AX immunofluorescence and immunoblot evaluated the effect of
LB100 on radiation-induced DNA damage. Ultrastructural evidence for nuclear
damage was investigated using Raman imaging and transmission electron
microscopy. A xenograft model was established to determine potential clinical
utility of adding LB100 to irradiation.
RESULTS: PP2A inhibition in concert with irradiation demonstrated in vitro
growth inhibition. The combination of LB100 and radiation also induced
accumulation at the G2/M phase of the cell cycle, the stage most sensitive to
radiation-induced damage. LB100 enhanced radiation-induced DNA double-strand
breaks. Animals implanted with chordoma cells and treated with the combination
of LB100 and radiation demonstrated tumor growth delay.
CONCLUSIONS: Combining LB100 and radiation enhanced DNA damage-induced cell
death and delayed tumor growth in an animal model of chordoma. PP2A inhibition
by LB100 treatment may improve the effectiveness of radiation therapy for
chordoma. |
Which disease can be classified using the Koos Classification? | The Koos classification is used from vestibular schwannomas. It is designed to stratify tumors based on extrameatal extension and compression of the brainstem. | OBJECTIVE: The aim of this study was to compare quality of life (QOL) in small
unilateral vestibular schwannoma (VS) patients managed by microsurgery,
radiotherapy or observation.
STUDY DESIGN: A retrospective chart review.
METHODS: The study included a total of 142 patients with VS stage 1 or 2
according to the Koos classification and treated between January 2004 and
December 2015. Microsurgery, radiotherapy and observation groups comprised 43,
46 and 53 patients, respectively. All patients completed four QOL
(questionnaires: Short-Form Health Survey 36, Hearing Handicap Inventory,
Tinnitus Handicap Inventory and Dizziness Handicap Inventory Short-Form).
Clinical symptoms and QOL were compared among groups.
RESULTS: The average time interval between management and filling in the
questionnaires was 66 months. There was no difference in QOL between the three
groups on any of the four questionnaires. The most debilitating symptom was
vertigo for all three groups. Tinnitus was a pejorative factor in the surgery
group. Hearing level was deteriorated after microsurgery but there was no
significant difference between the radiotherapy group and the middle fossa
approach.
CONCLUSION: Patients with small VS stage 1 and 2 had similar QOL, irrespective
of management by observation, radiotherapy or microsurgery. The overall
predictor for long-term reduced QOL was vertigo. Vestibular rehabilitation could
improve QOL in symptomatic patients. BACKGROUND: The Koos classification of vestibular schwannomas is designed to
stratify tumors based on extrameatal extension and compression of the brainstem.
While this classification system is widely reported in the literature, to date
no study has assessed its reliability.
OBJECTIVE: To assess the intra- and inter-rater reliability of the Koos
classification system.
METHODS: After institutional review board approval was obtained, a
cross-sectional group of the Magnetic Resoce imagings of 40 patients with
vestibular schwannomas varying in size comprised the study sample. Four raters
were selected to assign a Koos grade to 50 total scans. Inter- and intrarater
reliability were calculated and reported using Fleiss' kappa, Kendall's W, and
Intraclass correlation coefficient (ICC).
RESULTS: Inter-rater reliability was found to be substantial when measured using
Fleiss' kappa (.71), extremely strong using Kendall's W (.92), and excellent as
calculated by ICC (.88).Intrarater reliability was perfect for 3 out of 4 raters
as assessed using weighted kappa, Kendall's W and ICC, with the intrarater
agreement for the fourth rater measured as extremely high.
CONCLUSION: We have demonstrated that the Koos classification system for
vestibular schwannoma is a reliable method for tumor classification. This study
lends further support to the results of current literature using Koos grading
system. Further studies are required to evaluate its validity and utility in
counseling patients with regard to outcomes. OBJECTIVE: To determine whether cervical vestibular evoked myogenic potentials
(cVEMPs) are predictive of hearing preservation in patients undergoing
vestibular schwannoma removal through middle fossa craniotomy approach.
STUDY DESIGN: Retrospective case study.
SETTING: Tertiary referral center.
PATIENTS: Eighteen patients who underwent a middle fossa craniotomy for
vestibular schwannoma (stage I or II of Koos classification) with attempted
hearing preservation from January 2008 to February 2016 were retrospectively
reviewed.
INTERVENTION: Pre-surgical cVEMPs test, videonystagmography (caloric test), and
magnetic resoce imaging (MRI) as well as a pre- and post-surgical audiometry
test.
MAIN OUTCOME MEASURES: cVEMPs parameters including amplitude asymmetry ratio
(AR), P13, and N23 latencies and peak-to-peak amplitude between P13 and N23
waves were calculated. Hearing data were classified according to the AAO-HNS
hearing classes. The nerve of origin of the tumor was specified during surgery
and the largest tumor diameter was measure on MRI axial plane on T2-CISS weighed
images.
RESULTS: Preoperative amplitude asymmetry ratio was lower (n = 15, Mann-Whitney
U test, p < 0.001) in the group with postoperative hearing preservation (n = 11)
compared with the group with postoperative hearing preservation failure (n = 4).
The positive predictive value of an AR less than 24% to assess postoperative
hearing preservation is 91.6%. Tumor size and localization were not correlated
with cVEMPs, nor with caloric testing in this group of small-sized
intracanalicular vestibular schwannomas.
CONCLUSIONS: Our data suggest that cVEMPs may help predict hearing preservation
outcome in vestibular schwannoma surgery via the middle fossa craniotomy
approach. |
What is circulating free DNA ( cfDNA)? | Known to be present in the blood of cancer patients for decades, cell-free DNA (cfDNA) is beginning to inform on tumor genetics, tumor burden, and mechanisms of progression and drug resistance. | OBJECTIVE: This study aimed to determine the principal factors contributing to
the cost of avoiding a birth with Down syndrome by using cell-free DNA (cfDNA)
to replace conventional screening.
METHODS: A range of unit costs were assigned to each item in the screening
process. Detection rates were estimated by meta-analysis and modeling. The
marginal cost associated with the detection of additional cases using cfDNA was
estimated from the difference in average costs divided by the difference in
detection.
RESULTS: The main factor was the unit cost of cfDNA testing. For example,
replacing a combined test costing $150 with 3% false-positive rate and invasive
testing at $1000, by cfDNA tests at $2000, $1500, $1000, and $500, the marginal
cost is $8.0, $5.8, $3.6, and $1.4m, respectively. Costs were lower when
replacing a quadruple test and higher for a 5% false-positive rate, but the
relative importance of cfDNA unit cost was unchanged. A contingent policy
whereby 10% to 20% women were selected for cfDNA testing by conventional
screening was considerably more cost-efficient. Costs were sensitive to cfDNA
uptake.
CONCLUSION: Universal cfDNA screening for Down syndrome will only become
affordable by public health purchasers if costs fall substantially. Until this
happens, the contingent use of cfDNA is recommended. PURPOSE: Chemotherapy is an integral part of the treatment of castration
resistant prostate cancer. With the introduction of new drugs the need to
identify nonresponders is increasing. To our knowledge there are no prognostic
parameters to date for use upon the initiation of any treatment.
MATERIALS AND METHODS: cfDNA was isolated from a serum specimen before
chemotherapy. Its value was correlated to recurrence-free and overall survival
using Kaplan-Meier curves. Univariate and multivariate Cox regression analysis
was performed to identify independent predictors.
RESULTS: Of 59 men 48 (81.4%) had a measurable prostate specific antigen
decrease from baseline. Median followup was 15.0 months (range 2.4 to 58.4). The
median cfDNA concentration in all men in this study was 27.71 ng/ml (mean
32.64). A threshold of 55.03 ng/ml was significantly associated with a poor
prostate specific antigen response of less than 30% (p = 0.005). On univariate
and multivariate analysis circulating cfDNA was an independent predictor of
overall survival (HR 0.36, 95% CI 0.13-0.97, p = 0.044 and HR 0.34, 95% CI
0.12-0.91, p = 0.032, respectively). Limitations of the study are its
retrospective character, and first and second line therapies.
CONCLUSIONS: Our trial shows that the cfDNA concentration before therapy may be
a useful predictive and prognostic biomarker for prostate specific antigen
response and survival. Testing of tumor tissue remains the recommended method for detecting the
presence of somatic mutations in human maligcies. V600E is the most frequent
somatic point mutation in metastatic melanoma, providing a unique molecular
marker for this maligcy. In addition, tumors carrying this mutation are
primary candidates for BRAF-targeted therapy. Although metastatic melanoma
patients usually have sufficient tumor tissue available for genetic analyses,
the detection of V600E in blood can have prognostic and predictive value. In
addition, patients are rarely re-biopsied and genetic testing in blood can be
useful for monitoring response to therapy. Cell-free DNA (cfDNA) and cell-free
RNA (cfRNA), RNA associated to platelets and circulating tumor cells (CTCs) are
some of the materials that can be derived from the blood of cancer patients.
cfDNA can be easily purified from serum and plasma and contains DNA fragments of
tumor origin. For this reason, it is the most widely used material for the
detection of somatic mutations in blood. Several methodologies have been used to
determine V600E status in the cfDNA of metastatic melanoma and some studies have
demonstrated that the identification and follow-up of V600E in cfDNA can have
prognostic and predictive value. Precision oncology is predicated upon the ability to detect specific actionable
genomic alterations and to monitor their adaptive evolution during treatment to
counter resistance. Because of spatial and temporal heterogeneity and
comorbidities associated with obtaining tumor tissues, especially in the case of
metastatic disease, traditional methods for tumor sampling are impractical for
this application. Known to be present in the blood of cancer patients for
decades, cell-free DNA (cfDNA) is beginning to inform on tumor genetics, tumor
burden, and mechanisms of progression and drug resistance. This substrate is
amenable for inexpensive noninvasive testing and thus presents a viable approach
to serial sampling for screening and monitoring tumor progression. The
fragmentation, low yield, and variable admixture of normal DNA present
formidable technical challenges for realization of this potential. This review
summarizes the history of cfDNA discovery, its biological properties, and
explores emerging technologies for clinically relevant sequence-based analysis
of cfDNA in cancer patients. Molecular barcoding (or Unique Molecular
Identifier, UMI)-based methods currently appear to offer an optimal balance
between sensitivity, flexibility, and cost and constitute a promising approach
for clinically relevant assays for near real-time monitoring of
treatment-induced mutational adaptations to guide evidence-based precision
oncology. Mol Cancer Res; 14(10); 898-908. ©2016 AACR. INTRODUCTION: Tumour burden is a prognostic biomarker in metastatic melanoma.
However, tumour burden is difficult to measure and there are currently no
reliable surrogate biomarkers to easily and reliably determine it. The aim of
this study was to assess the potential of plasma total cell free DNA as
biomarker of tumour burden and prognosis in metastatic melanoma patients.
MATERIALS AND METHODS: A prospective biomarker cohort study for total plasma
circulating cell-free DNA (cfDNA) concentration was performed in 43 metastatic
melanoma patients. For 38 patients, paired blood collections and scan
assessments were available before treatment and at first response evaluation.
Tumour burden was calculated as the sum of volumes from three-dimensional
radiological measurements of all metastatic lesions in individual patients.
RESULTS: Baseline cfDNA concentration correlated with pre-treatment tumour
burden (ρ = 0.52, P < 0.001). Baseline cfDNA levels correlated significantly
with hazard of death and overall survival, and a cut off value of 89 pg/μl
identified two distinct prognostic groups (HR = 2.22 for high cfDNA, P = 0.004).
Patients with cfDNA ≥89 pg/μl had shorter OS (10.0 versus 22.7 months,
P = 0.009; HR = 2.22 for high cfDNA, P = 0.004) and the significance was
maintained when compared with lactic dehydrogenase (LDH) in a multivariate
analysis. We also found a correlation between the changes of cfDNA and
treatment-related changes in tumour burden (ρ = 0.49, P = 0.002). In addition,
the ratio between baseline cfDNA and tumour burden was prognostic (HR = 2.7 for
cfDNA/tumour volume ≥8 pg/(μl*cm3), P = 0.024).
CONCLUSIONS: We have demonstrated that cfDNA is a surrogate marker of tumour
burden in metastatic melanoma patients, and that it is prognostic for overall
survival. Cell-free fetal DNA analysis for non-invasive prenatal screening of fetal
chromosomal aneuploidy has been widely adopted for clinical use. Fetal monogenic
diseases have also been shown to be amenable to non-invasive detection by
maternal plasma DNA analysis. A number of recent technological developments in
this area has increased the level of clinical interest, particularly as one
approach does not require customized reagents per mutation. The mutational
status of the fetus can be assessed by determining which parental haplotype that
fetus has inherited based on the detection of haplotype-associated SNP alleles
in maternal plasma. Such relative haplotype dosage analysis requires the input
of the parental haplotype information for interpretation of the fetal
inheritance pattern from the maternal plasma DNA data. The parental haplotype
information can be obtained by direct means, reducing the need to infer
haplotypes using DNA from other family members. The technique also allows the
assessment of complex mutations and has multiplexing capabilities where a number
of genes and mutations can be assessed at the same time. These advantages allow
non-invasive prenatal diagnosis of fetal monogenic diseases to be much more
scalable. These applications may drive the next wave of clinical adoption of
cell-free fetal DNA testing. © 2018 The Authors Prenatal Diagnosis Published by
John Wiley & Sons Ltd. |
What are the in vivo effects of AZD8601? | AZD8601 administration in vivo results in pronounced, sustained and dose-dependent vasodilation, blood flow upregulation, and neovessel formation, in striking contrast to those induced by recombinant human VEGF-A protein, a non-translatable variant of AZD8601, and citrate/saline vehicle. Moreover, sequential dosing of AZD8601 improves vascularization and tissue oxygenation of the wound bed, leading to accelerated re-epithelialization during the early phase of diabetic wound healing. | |
Which receptor does amantadine antagonize? | Amantadine is an N-methyl-D-aspartic acid or N-methyl-D-aspartate (NMDA) receptor antagonist. | |
Which characteristics are used in the SLEDAI index for SLE patients? | The SLEDAi is a "weighted" index of 9 organ systems for disease activity in SLE which includes: 8 for central nervous system and vascular, 4 for renal and musculoskeletal, 2 for serosal, dermal, immunologic, and 1 for constitutional and hematologic. | OBJECTIVE: To standardize outcome measures in systemic lupus erythematosus
(SLE). Three indices were identified which could adequately describe outcome
(disease activity, damage from disease, and health status); we describe here the
development of the Disease Activity Index.
METHODS: Twenty-four variables were identified as important factors in a disease
activity index. These were used to generate 574 patient profiles, which were
rated on a disease activity scale of 0-10 by 14 rheumatologists. A second rating
of 10 of the profiles yielded scores that were not significantly different from
the first, indicating that experienced clinicians can reliably make global
estimates of disease activity. Multiple regression models were used to estimate
the relative importance of the 24 clinical variables in the physicians' global
rating of disease activity. These were estimated on a "training set" of 75% of
physicians' ratings, and then validated on a "testing set," consisting of the
remaining 25% of physicians' ratings.
RESULTS: The explanatory power of the models in the training set was high (R2 =
0.93). The models' regression coefficients for the organ systems were simplified
for easier use in clinical practice. This generated a "weighted" index of 9
organ systems for disease activity in SLE, the SLEDAI, as follows: 8 for central
nervous system and vascular, 4 for renal and musculoskeletal, 2 for serosal,
dermal, immunologic, and 1 for constitutional and hematologic. The maximum
theoretical score is 105, but in practice, few patients have scores greater than
45. The SLEDAI predicted well the physicians' ratings in the testing set
(Pearson's correlation coefficients = 0.64-0.79).
CONCLUSION: The SLEDAI is a validated model of experienced clinicians' global
assessments of disease activity in lupus. It represents the consensus of a group
of experts in the field of lupus research. OBJECTIVE: To assess the validity, reliability, and feasibility of the Systemic
Lupus Activity Measure-Revised (SLAM-R), the Mexican version of the Systemic
Lupus Erythematosus Disease Activity Index (MEX-SLEDAI), and a Modified
SLEDAI-2000 (SLEDAI-2K) compared with the SLEDAI-2K in a multiethnic population
of patients with SLE.
METHODS: We studied 92 SLE patients from 3 US geographic areas (Alabama, Texas,
and Puerto Rico). Assessment occurred during regular outpatient, inpatient, or
study encounters. A trained physician scored the 4 instruments and also assessed
disease activity globally [physician global assessment (PGA)]. Convergent (with
SLEDAI-2K) and construct validity (with PGA) were determined by Spearman rank
(rs) correlation test. Level of agreement between the instruments was assessed
using Bland-Altman plots. Discrimit validity (distinguishing clearly active
vs mildly/nonactive disease) was assessed considering the SLEDAI-2K (and the
PGA) as the gold standard. Feasibility was explored by cost analyses.
RESULTS: The SLAM-R, the MEX-SLEDAI, and the Modified SLEDAI-2K were highly
correlated with the SLEDAI-2K (rs = 0.566, 0.755, 0.924, respectively) and with
the PGA (rs = 0.650, 0.540, 0.634, respectively). The 3 instruments showed good
agreement with the SLEDAI-2K (Bland-Altman plots). The Modified SLEDAI-2K had
better discrimit validity than the SLAM-R and the MEX-SLEDAI. The Modified
SLEDAI-2K was the least expensive instrument.
CONCLUSION: The SLAM-R, the MEX-SLEDAI, and the Modified SLEDAI-2K are adequate
options for assessment of SLE disease activity; they are also less costly than
the SLEDAI-2K. OBJECTIVE: o determine if the variability of the Systemic Lupus Erythematosus
Disease Activity Index 2000 (SLEDAI-2K), along with the Adjusted Mean SLEDAI-2K
(AMS), can better predict major outcomes in SLE than the AMS alone.
METHODS: Patients were followed in the Lupus Clinic at 2-6 month intervals.
Clinical and laboratory information necessary to compute the SLEDAI-2K and
Systemic Lupus International Collaborating Clinics/American College of
Rheumatology damage index was collected prospectively and entered onto a
computerized database. Patients followed for a minimum of 3 visits, and without
absence for a period > 18 consecutive months, were included in the study. Six
different approaches to measure variability of SLEDAI-2K were evaluated for each
visit, along with AMS. Approaches were the standard deviation, the slope,
average rate of change by visit, the range, the coefficient of variation, and
the Percentage of the visits with a change in SLEDAI-2K > or = 3. The SLE
outcomes under study were death, presence of damage, coronary artery disease
(CAD), and osteonecrosis (ON). The predictability of each outcome was evaluated
through time-dependent covariate survival analyses. Regression models included
other known major risk factors such as sex, age at diagnosis, SLEDAI-2K at
presentation, and disease duration.
RESULTS: Five hundred seventy-five patients seen from 1970 to 2002 were
included. The average time between visits was 4.0 +/- 2.2 months. Eighty-five
patients died, 325 developed damage, 55 had CAD, and 68 had ON. None of the 6
variability measures added more statistical significance in the prediction of
any of the 4 outcomes. For the prediction of survival, AMS [hazard ratio (HR) =
1.16, p < 0.0001] and age at diagnosis (HR 1.05, p < 0.0001) were the only
significant risk factors. For presence of damage, AMS (HR 1.06, p < 0.0001), age
at diagnosis (HR 1.02, p = 0.0004), and disease duration (HR 1.05, p < 0.0001)
were predictors. CAD was predicted by AMS (HR 1.12, p = 0.0003), male sex (HR
2.31, p = 0.02), age at diagnosis (HR 1.06, p < 0.0001), and disease duration
(HR 1.10, p < 0.0001). For ON, SLEDAI-2K at presentation (HR 1.04, p = 0.003)
and disease duration (HR 0.92, p = 0.05) were significant risk factors.
CONCLUSION: Multivariate analysis revealed that AMS, independent of variability
of the SLEDAI-2K, is an important predictor of major outcomes in SLE. OBJECTIVE: To develop and validate a modification of SLEDAI-2K to accurately
describe disease activity while accounting for glucocorticoid (GC) doses.
METHODS: The first two phases focused on the development of the index. Phase 1:
identification of scenarios of real patients seen prospectively in a
longitudinal cohort. Phase 2: derivation of an equation that explains the
association between SLEDAI-2K and GC doses using physician global assessment as
the external construct. Phase 3: comparison of SLEDAI-2K and SLEDAI-2K GC
(SLEDAI-2KG), using different cut-off points (4-7), in identifying responders in
response to therapy.
RESULTS: In phase 1, 150 scenarios with different organ involvement and a range
of GC doses were identified. In phase 2, three rheumatologists ranked disease
activity using physician global assessment. A quadratic linear regression model
relating GC doses and SLEDAI-2K resulted in the following equation: SLEDAI-2KG
score = SLEDAI-2K score + [0.32 × GC - 0.0031 × GC2]. The weighted score of
different GC doses was derived. In phase 3, SLEDAI-2KG identified more
responders in a total of 111 patients at 6 months (84 vs 93%) and at 12 months
(76 vs 92%) compared with SLEDAI-2K. SLEDAI-2KG performances were superior to
SLEDAI-2K with all cut-off points (5-7).
CONCLUSION: We developed a modification of SLEDAI-2K, SLEDAI-2KG, that describes
disease activity while accounting for GC dose category. SLEDAI-2KG identifies
more responders compared with SLEDAI-2K. |
Which medication are included in the Polycap polypill? | Polycap polypil contains aspirin, 100 mg; atenolol, 50 mg; ramipril, 5 mg; thiazide, 12.5 mg; and simvastatin, 20 mg. It is taken as two capsules once daily. | BACKGROUND: The combination of three blood-pressure-lowering drugs at low doses,
with a statin, aspirin, and folic acid (the polypill), could reduce
cardiovascular events by more than 80% in healthy individuals. We examined the
effect of the Polycap on blood pressure, lipids, heart rate, and urinary
thromboxane B2, and assessed its tolerability.
METHODS: In a double-blind trial in 50 centres in India, 2053 individuals
without cardiovascular disease, aged 45-80 years, and with one risk factor were
randomly assigned, by a central secure website, to the Polycap (n=412)
consisting of low doses of thiazide (12.5 mg), atenolol (50 mg), ramipril (5
mg), simvastatin (20 mg), and aspirin (100 mg) per day, or to eight other
groups, each with about 200 individuals, of aspirin alone, simvastatin alone,
hydrochlorthiazide alone, three combinations of the two blood-pressure-lowering
drugs, three blood-pressure-lowering drugs alone, or three
blood-pressure-lowering drugs plus aspirin. The primary outcomes were LDL for
the effect of lipids, blood pressure for antihypertensive drugs, heart rate for
the effects of atenolol, urinary 11-dehydrothromboxane B2 for the antiplatelet
effects of aspirin, and rates of discontinuation of drugs for safety. Analysis
was by intention to treat. This study is registered with ClinicalTrials.gov,
number NCT00443794.
FINDINGS: Compared with groups not receiving blood-pressure-lowering drugs, the
Polycap reduced systolic blood pressure by 7.4 mm Hg (95% CI 6.1-8.1) and
diastolic blood pressure by 5.6 mm Hg (4.7-6.4), which was similar when three
blood-pressure-lowering drugs were used, with or without aspirin. Reductions in
blood pressure increased with the number of drugs used (2.2/1.3 mm Hg with one
drug, 4.7/3.6 mm Hg with two drugs, and 6.3/4.5 mm Hg with three drugs). Polycap
reduced LDL cholesterol by 0.70 mmol/L (95% CI 0.62-0.78), which was less than
that with simvastatin alone (0.83 mmol/L, 0.72-0.93; p=0.04); both reductions
were greater than for groups without simvastatin (p<0.0001). The reductions in
heart rate with Polycap and other groups using atenolol were similar (7.0 beats
per min), and both were significantly greater than that in groups without
atenolol (p<0.0001). The reductions in 11-dehydrothromboxane B2 were similar
with the Polycap (283.1 ng/mmol creatinine, 95% CI 229.1-337.0) compared with
the three blood-pressure-lowering drugs plus aspirin (350.0 ng/mmol creatinine,
294.6-404.0), and aspirin alone (348.8 ng/mmol creatinine, 277.6-419.9) compared
with groups without aspirin. Tolerability of the Polycap was similar to that of
other treatments, with no evidence of increasing intolerability with increasing
number of active components in one pill.
INTERPRETATION: This Polycap formulation could be conveniently used to reduce
multiple risk factors and cardiovascular risk. BACKGROUND: The Polycap (polypill; aspirin [acetylsalicylic acid], ramipril,
simvastatin, atenolol, and hydrochlorothiazide) was found to be safe and
effective for reducing multiple cardiovascular risk factors in The Indian
Polycap Study (TIPS).
OBJECTIVE: We evaluated the bioavailability of each ingredient of the Polycap
and determined any drug-drug interactions relative to single component reference
preparations.
METHODS: The bioavailability of the ingredients of the Polycap (T; test) when
formulated as a single capsule was compared with that of identical capsules with
each of its ingredients administered separately (R; reference) in a five-arm,
randomized, single-dose, two-period, two-treatment, two-sequence, crossover
trial with at least a 2-week washout period in a total of 195 healthy
volunteers. Plasma concentrations of each drug and, where applicable, its active
metabolite were measured using validated liquid chromatography-tandem mass
spectrometry and ultra-performance liquid chromatography. Mean pharmacokinetic
parameters and their standard deviations were computed for each analyte.
RESULTS: Comparative bioavailability was computed and no drug-drug interactions
and no difference in comparative bioavailability were concluded for each
ingredient based on point estimates of the T/R ratio of the geometric means
falling within 80-125% for peak plasma concentration (C(max)), area under the
plasma concentration-time curve from time zero to the last measurable
concentration (AUC(t)), and AUC from time zero to infinity (AUC(infinity)). The
T/R ratio for C(max), AUC(t) and AUC(infinity) was within 80-125% for atenolol,
hydrochlorothiazide, ramipril, ramiprilat and dose-normalized salicylic acid.
However, for simvastatin, the T/R point estimates for C(max), AUC(t) and
AUC(infinity) for Ln-transformed data were significantly lower ( approximately
3-4%) than the lower bound of 80%. For its active metabolite, simvastatin acid,
these estimates were significantly higher ( approximately 25-35%) than the
higher bound of 125%. Thus, the increased bioavailability of active simvastatin
acid appeared to compensate for the loss of bioavailability of simvastatin.
CONCLUSION: The Polycap was found to be effective and safe in the previously
published TIPS trial. The present study in healthy volunteers establishes that
Polycap is safe (no serious adverse events) and well tolerated, and that there
is no indication of pharmacokinetic drug-drug interactions for any of the
ingredients, with their bioavailabilities being well preserved. Objectives The aim of the present study was to estimate the cost-effectiveness
of the polypill in the primary prevention of cardiovascular disease. Design A
health economic modelling study. Setting Primary healthcare in the Netherlands.
Participants Simulated individuals from the general Dutch population, aged 45-75
years. Interventions Opportunistic screening followed by prescription of the
polypill to eligible individuals. Eligibility was defined as having a minimum
10-year risk of cardiovascular death as assessed with the Systematic Coronary
Risk Evaluation function of alternatively 5%, 7.5% or 10%. Different versions of
the polypill were considered, depending on composition: (1) the Indian polycap,
with three different types of blood pressure-lowering drugs, a statin and
aspirin; (2) as (1) but without aspirin and (3) as (2) but with a double statin
dose. In addition, a scenario of (targeted) separate antihypertensive and/or
statin medication was simulated. Primary outcome measures Cases of acute
myocardial infarction or stroke prevented, quality-adjusted life years (QALYs)
gained and the costs per QALY gained. All interventions were compared with usual
care. Results All scenarios were cost-effective with an incremental
cost-effectiveness ratio between €7900 and 12 300 per QALY compared with usual
care. Most health gains were achieved with the polypill without aspirin and
containing a double dose of statins. With a 10-year risk of 7.5% as the
threshold, this pill would prevent approximately 3.5% of all cardiovascular
events. Conclusions Opportunistic screening based on global cardiovascular risk
assessment followed by polypill prescription to those with increased risk offers
a cost-effective strategy. Most health gain is achieved by the polypill without
aspirin and a double statin dose. BACKGROUND: There is an unprecedented rise in the prevalence of stroke in
sub-Saharan Africa (SSA). Secondary prevention guidelines recommend that
antihypertensive, statin and antiplatelet therapy be initiated promptly after
ischemic stroke and adhered to in a persistent fashion to achieve optimal
vascular-risk reduction. However, these goals are seldom realized in routine
clinical care settings in SSA due to logistical challenges. We seek to assess
whether a polypill containing fixed doses of three antihypertensive agents, a
statin and antiplatelet therapy taken once daily per os for 12 months among
recent stroke survivors would result in carotid intimal thickness regression
compared with usual care (UC).
METHODS: The Stroke Minimization through Additive Anti-atherosclerotic Agents in
Routine Treatment (SMAART) trial is a phase 2, open-label, evaluator-blinded
trial involving 120 Ghanaian recent-ischemic-stroke survivors. Using a
computer-generated sequence, patients will be randomly allocated 1:1 into either
the intervention arm or UC. Patients in the intervention arm will receive
Polycap DS® (containing aspirin, 100 mg; atenolol, 50 mg; ramipril, 5 mg;
thiazide, 12.5 mg; simvastatin, 20 mg) taken as two capsules once daily.
Patients in the UC will receive separate, individual secondary preventive
medications prescribed at the physician's discretion. Both groups will be
followed for 12 months to assess changes in carotid intimal thickness regression
- a surrogate marker of atherosclerosis - as primary outcome measure. Secondary
outcome measures include adherence to therapy, safety and tolerability,
health-related quality of life, patient satisfaction, functional status,
depression and cognitive dysfunction.
DISCUSSION: An efficacy-suggesting SMAART trial could inform the future design
of a multi-center, double-blinded, placebo-controlled, parallel-group,
randomized controlled trial comparing the clinical efficacy of the polypill
strategy for vascular risk moderation among stroke survivors in SSA.
TRIAL REGISTRATION: ClinicalTrials.gov , ID: NCT03329599 . Registered on 11
February 2017. BACKGROUND: It is hypothesized that in individuals without clinical
cardiovascular disease (CVD), but at increased CVD risk, a 50% to 60% reduction
in CVD risk could be achieved using fixed dose combination (FDC) therapy
(usually comprised of multiple blood-pressure agents and a statin [with or
without aspirin]) in a single "polypill". However, the impact of a polypill in
preventing clinical CV events has not been evaluated in a large randomized
controlled trial.
METHODS: TIPS-3 is a 2x2x2 factorial randomized controlled trial that will
examine the effect of a FDC polypill on major CV outcomes in a primary
prevention population. This study aims to determine whether the Polycap
(comprised of atenolol, ramipril, hydrochlorothiazide, and a statin) reduces CV
events in persons without a history of CVD, but who are at least at intermediate
CVD risk. Additional interventions in the factorial design of the study will
compare the effect of (1) aspirin versus placebo on CV events (and cancer), (2)
vitamin D versus placebo on the risk of fractures, and (3) the combined effect
of aspirin and the Polycap on CV events.
RESULTS: The study has randomized 5713 participants across 9 countries. Mean age
of the study population is 63.9 years, and 53% are female. Mean INTERHEART risk
score is 16.8, which is consistent with a study population at intermediate CVD
risk.
CONCLUSION: Results of the TIP-3 study will be key to determining the
appropriateness of FDC therapy as a strategy in the global prevention of CVD. |
Describe the mechanism of action of Luspatercept. | Luspatercept is a recombinant soluble activin type-II receptor-IgG-Fc fusion protein that blocks transforming growth factor beta (TGF b) superfamily inhibitors of erythropoiesis. Luspatercept is tested for the treatment of various types of anemias. | BACKGROUND: Myelodysplastic syndromes are characterised by ineffective
erythropoiesis. Luspatercept (ACE-536) is a novel fusion protein that blocks
transforming growth factor beta (TGF β) superfamily inhibitors of
erythropoiesis, giving rise to a promising new investigative therapy. We aimed
to assess the safety and efficacy of luspatercept in patients with anaemia due
to lower-risk myelodysplastic syndromes.
METHODS: In this phase 2, multicentre, open-label, dose-finding study
(PACE-MDS), with long-term extension, eligible patients were aged 18 years or
older, had International Prognostic Scoring System-defined low or intermediate 1
risk myelodysplastic syndromes or non-proliferative chronic myelomonocytic
leukaemia (white blood cell count <13 000/μL), and had anaemia with or without
red blood cell transfusion support. Enrolled patients were classified as having
low transfusion burden, defined as requiring less than 4 red blood cell units in
the 8 weeks before treatment (and baseline haemoglobin <10 g/dL), or high
transfusion burden, defined as requiring 4 or more red blood cell units in the 8
weeks before treatment. Patients received luspatercept subcutaneously once every
21 days at dose concentrations ranging from 0·125 mg/kg to 1·75 mg/kg bodyweight
for five doses (over a maximum of 12 weeks). Patients in the expansion cohort
were treated with 1·0 mg/kg luspatercept; dose titration up to 1·75 mg/kg was
allowed, and patients could be treated with luspatercept for a maximum of 5
years. Patients in the base study were assessed for response and safety after 12
weeks in order to be considered for enrolment into the extension study. The
primary endpoint was the proportion of patients achieving modified International
Working Group-defined haematological improvement-erythroid (HI-E), defined as a
haemoglobin concentration increase of 1·5 g/dL or higher from baseline for 14
days or longer in low transfusion burden patients, and a reduction in red blood
cell transfusion of 4 or more red blood cell units or a 50% or higher reduction
in red blood cell units over 8 weeks versus pre-treatment transfusion burden in
high transfusion burden patients. Patient data were subcategorised by:
luspatercept dose concentrations (0·125-0·5 mg/kg vs 0·75-1·75 mg/kg); pre-study
transfusion burden (high transfusion burden vs low transfusion burden, defined
as ≥4 vs <4 red blood cell units per 8 weeks); pre-study serum erythropoietin
concentration (<200 IU/L, 200-500 IU/L, and >500 IU/L); presence of 15% or more
ring sideroblasts; and presence of SF3B1 mutations. Efficacy analyses were
carried out on the efficacy evaluable and intention-to-treat populations. This
trial is currently ongoing. This study is registered with ClinicalTrials.gov,
numbers NCT01749514 and NCT02268383.
FINDINGS: Between Jan 21, 2013, and Feb 12, 2015, 58 patients with
myelodysplastic syndromes were enrolled in the 12 week base study at nine
treatment centres in Germany; 27 patients were enrolled in the dose-escalation
cohorts (0·125-1·75 mg/kg) and 31 patients in the expansion cohort (1·0-1·75
mg/kg). 32 (63% [95% CI 48-76]) of 51 patients receiving higher dose
luspatercept concentrations (0·75-1·75 mg/kg) achieved HI-E versus two (22% [95%
CI 3-60]) of nine receiving lower dose concentrations (0·125-0·5 mg/kg). Three
treatment-related grade 3 adverse events occurred in one patient each: myalgia
(one [2%]), increased blast cell count (one [2%]), and general physical health
deterioration (one [2%]). Two of these treatment-related grade 3 adverse events
were reversible serious grade 3 adverse events: one patient (2%) had myalgia and
one patient (2%) had general physical health deterioration.
INTERPRETATION: Luspatercept was well tolerated and effective for the treatment
of anaemia in lower-risk myelodysplastic syndromes and so could therefore
provide a novel therapeutic approach for the treatment of anaemia associated
with lower-risk myelodysplastic syndromes; further studies are ongoing.
FUNDING: Acceleron Pharma. New therapeutic proteins that trap circulating members of the transforming
growth factor (TGF) beta superfamily (activins and growth differentiation
factors) show promising effects on erythropoiesis and muscular growth. They are
dimeric recombit fusion proteins composed of the extracellular domain of a
human activin receptor (ActRIIA or IIB) linked to the Fc part of human IgG1.
Sotatercept (ActRIIA-Fc) and Luspatercept (a modified ActRIIB-Fc) in particular
are now in phase 2/3 of clinical trials against anemia and included in the
prohibited list established by the World Anti-Doping Agency. To prevent a
potential misuse by athletes in the near future, a robust and sensitive method
of detection is needed. We validated an approach adapted from an electrophoretic
method used for the detection of recombit erythropoietins that allowed
detection of various ActRIIA-Fc and ActRIIB-Fc proteins, including variants
produced in different cell types, after a single immuno-extraction step. After
separation by sodium dodecyl sulfate polyacrylamide gel electrophoresis
(SDS-PAGE), an initial testing procedure performed by single-blotting can
indicate the presence of an ActRII-Fc (indifferently type IIA or IIB). A
confirmation performed by double-blotting using different antibodies for
detection allows a more precise identification of the type of ActRII-Fc (IIA,
IIB). Starting from a few hundred microliters of serum or plasma, this method is
specific, sensitive, and easy to perform. It could easily be adopted by
anti-doping laboratories. Iso-electric focusing (IEF) was the first method established to discriminate
endogenous and recombit erythropoietins (rEPOs). It is still approved by the
World Anti-Doping Agency (WADA) as an initial testing procedure to detect
erythropoiesis stimulating agents (ESAs) in doping control samples. However
EPO-Fc, one of the prohibited rEPOs designated by WADA, is not detectable with
the actual IEF conditions. Other newly developed ESAs - luspatercept and
sotatercept, both activin receptor type II-Fc fusion proteins (ActRII-Fc) - are
also now prohibited and could be used in combination with rEPOs. Methods of
identification of ActRII-Fc in blood by SAR/SDS-PAGE have been described, but
not by IEF. Here we detail improvements in blood sample preparation and IEF
analysis: A combined immuno-purification of EPOs and ActRII-Fc proteins in a
single procedure, an appropriate isoforms separation for all proteins using new
pre-loading and gel conditions, and a single detection of all rEPOs and
ActRII-Fc proteins after successive incubation with anti-EPO and anti-ActRII
antibodies. With these changes, distinctive profiles for all the ESAs were
obtained by IEF. Therefore, IEF could be used as a screening method to detect a
wide spectrum of prohibited ESAs in blood samples prior to specific confirmation
for the identified rEPO or ActRII-Fc. Therapeutic proteins are a continuously growing class of pharmaceuticals and
comprise several drug candidates with potential performance-enhancing
properties. In particular, activin receptor competitors, such as the ActRII-Fc
fusion proteins Sotatercept (ActRIIA-Fc) and Luspatercept (modified ActRIIB-Fc),
have the potential for being misused as doping agents in sports as they were
found to inhibit negative regulators of late-stage erythropoiesis. Within this
study, ammonium sulfate precipitation, immunoaffinity purification, tryptic
digestion, and liquid chromatography-tandem mass spectrometry (LC-MS/MS) were
employed to develop an assay for the combined detection of Sotatercept and
Luspatercept in doping control serum samples. The assay was optimized,
comprehensively characterized, and found to be fit-for-purpose for application
to sports drug testing. It complements existing tests for ActRII-Fc fusion
proteins and expands the range of available detection methods for novel protein
therapeutics. PURPOSE OF REVIEW: Anaemia is a common haematological presentation in patients
with bone marrow failure, yet a challenging condition to treat. As anaemia has a
direct impact on the patient's symptoms, managing anaemia in the common bone
marrow failure conditions, such as myelodysplastic syndrome will help to improve
the quality of life. This review discusses the available treatment options and
the benefit of improving the haemoglobin level.
RECENT FINDINGS: Managing anaemia effectively has shown to improve the patient
outcome, yet treatment option remain limited. Recently, activin inhibitors such
as Luspatercept have shown to be effective in patients' refractory to ESAs and
further clinical trials are ongoing to explore this further.
SUMMARY: Transfusion still remains the mainstay of treatment in patients not
suitable, lost response or refractory to erythropoiesis-stimulating agents
(ESAs). Majority of these patients are not suitable for definite treatment
options such as bone marrow transplantation. The aim of treatment remains
improving the quality of life and newer therapeutic options may offer better and
more sustained response. |
Which method has been developed for mapping of Transcription Start Sites (TSS) starting from nanograms of RNA? | SLIC-CAGE has been developed as a method to identify transcriptome-wide the binding sites of transcription start sites (TSSs) using a simple two-step protocol with 500-50,000 cells and reveals the interplay between genomic locations of DNA-binding proteins, transcription, individual nucleosomes and transcriptional starting sites. | |
What are the molecular and cellular effects of LB-100 on ovarian carcinoma cells following cisplatin treatment? | LB100 sensitized ovarian carcinoma lines to cisplatin-mediated cell death. Sensitization via LB100 was mediated by abrogation of cell-cycle arrest induced by cisplatin. Loss of the cisplatin-induced checkpoint correlated with decreased Wee1 expression, increased cdc2 activation, and increased mitotic entry (p-histone H3). LB100 also induced constitutive hyperphosphorylation of DDR proteins (BRCA1, Chk2, and gH2AX), altered the chronology and persistence of JNK activation, and modulated the expression of 14-3-3 binding sites. | Despite early positive response to platinum-based chemotherapy, the majority of
ovarian carcinomas develop resistance and progress to fatal disease. Protein
phosphatase 2A (PP2A) is a ubiquitous phosphatase involved in the regulation of
DNA-damage response (DDR) and cell-cycle checkpoint pathways. Recent studies
have shown that LB100, a small-molecule inhibitor of PP2A, sensitizes cancer
cells to radiation-mediated DNA damage. We hypothesized that LB100 could
sensitize ovarian cancer cells to cisplatin treatment. We performed in vitro
studies in SKOV-3, OVCAR-8, and PEO1, -4, and -6 ovarian cancer lines to assess
cytotoxicity potentiation, cell-death mechanism(s), cell-cycle regulation, and
DDR signaling. In vivo studies were conducted in an intraperitoneal metastatic
mouse model using SKOV-3/f-Luc cells. LB100 sensitized ovarian carcinoma lines
to cisplatin-mediated cell death. Sensitization via LB100 was mediated by
abrogation of cell-cycle arrest induced by cisplatin. Loss of the
cisplatin-induced checkpoint correlated with decreased Wee1 expression,
increased cdc2 activation, and increased mitotic entry (p-histone H3). LB100
also induced constitutive hyperphosphorylation of DDR proteins (BRCA1, Chk2, and
γH2AX), altered the chronology and persistence of JNK activation, and modulated
the expression of 14-3-3 binding sites. In vivo, cisplatin sensitization via
LB100 significantly enhanced tumor growth inhibition and prevented disease
progression after treatment cessation. Our results suggest that LB100 sensitizes
ovarian cancer cells to cisplatin in vitro and in vivo by modulation of the DDR
pathway and cell-cycle checkpoint abrogation. |
Can LB-100 downregulate miR-33? | No, LB-100 has been reported to modulate (upregulate) only miR-181b-1. | Author information:
(1)Department of Hematology, The First Affiliated Hospital, College of Medicine,
Zhejiang University, Hangzhou, 310003, People's Republic of China.
(2)Department of Hematology, Hangzhou First People's Hospital, Hangzhou, 310006,
Zhejiang Province, People's Republic of China.
(3)Myelodysplastic Syndromes Diagnosis and Therapy Center, The First Affiliated
Hospital, College of Medicine, Zhejiang University, Hangzhou, 310003, People's
Republic of China.
(4)Department of Hematology, Yin Zhou People's Hospital, Ningbo, 315040,
Zhejiang Province, People's Republic of China.
(5)Surgical Neurology Branch, National Institute of Neurological Disorders and
Stroke, National Institutes of Health, Bethesda, MD, 20892, USA.
(6)Surgical Neurology Branch, National Institute of Neurological Disorders and
Stroke, National Institutes of Health, Bethesda, MD, 20892, USA.
[email protected].
(7)Department of Hematology, The First Affiliated Hospital, College of Medicine,
Zhejiang University, Hangzhou, 310003, People's Republic of China.
[email protected].
(8)Myelodysplastic Syndromes Diagnosis and Therapy Center, The First Affiliated
Hospital, College of Medicine, Zhejiang University, Hangzhou, 310003, People's
Republic of China. [email protected]. |
What is molecular radiotherapy? | Molecular radiotherapy is working through tumor-targeted radionuclides. | External-beam radiotherapy plays a critical role in the treatment of most
pediatric solid tumors. Particularly in children, achieving an optimal
therapeutic index to avoid damage to normal tissue is extremely important.
Consequently, in metastatic disease, the utility of external-beam radiotherapy
is limited. Molecular radiotherapy with tumor-targeted radionuclides may
overcome some of these challenges, but to date there exists no single
cancer-selective agent capable of treating various pediatric maligcies
independently of their histopathologic origin. We tested the therapeutic
potential of the clinical-grade alkyl-phospholipid ether analog CLR1404,
18-(p-iodophenyl)octadecyl phosphocholine, as a scaffold for tumor-targeted
radiotherapy of pediatric maligcies. Methods: Uptake of CLR1404 by pediatric
solid tumor cells was tested in vitro by flow cytometry and in vivo by PET/CT
imaging and dosimetry. The therapeutic potential of 131I-CLR1404 was evaluated
in xenograft models. Results: In vitro, fluorescent CLR1404-BODIPY showed
significant selective uptake in a variety of pediatric cancer lines compared
with normal controls. In vivo tumor-targeted uptake in mouse xenograft models
using 124I-CLR1404 was confirmed by imaging. Single-dose intravenous injection
of 131I-CLR1404 significantly delayed tumor growth in all rodent pediatric
xenograft models and extended animal survival while demonstrating a favorable
side effect profile. Conclusion:131I-CLR1404 has the potential to become a
tumor-targeted radiotherapeutic drug with broad applicability in pediatric
oncology. Because 131I-CLR1404 has entered clinical trials in adults, our data
warrant the development of pediatric clinical trials for this particularly
vulnerable patient population. PURPOSE: Neuroblastoma may be treated with molecular radiotherapy, 131I
meta-Iodobenzylguanidine and 177Lu Lutetium DOTATATE, directed at distinct
molecular targets: Noradrenaline Transporter Molecule (NAT) and Somatostatin
Receptor (SSTR2), respectively. This study used immunohistochemistry to evaluate
target expression in archival neuroblastoma tissue, to determine whether it
might facilitate clinical use of molecular radiotherapy.
METHODS: Tissue bank samples of formalin fixed paraffin embedded neuroblastoma
tissue from patients for whom clinical outcome data were available were
sectioned and stained with haematoxylin and eosin, and monoclonal antibodies
directed against NAT and SSTR2. Sections were examined blinded to clinical
information and scored for the percentage and intensity of tumour cells stained.
These data were analysed in conjunction with clinical data.
RESULTS: Tissue from 75 patients was examined. Target expression scores varied
widely between patients: NAT median 45%, inter-quartile range 25% - 65%; and
SSTR2 median 55%, interquartile range 30% - 80%; and in some cases heterogeneity
of expression between different parts of a tumour was observed. A weak positive
correlation was observed between the expression scores of the different targets:
correlation coefficient = 0.23, p = 0.05. MYCN amplified tumours had lower SSTR2
scores: mean difference 23% confidence interval 8% - 39%, p < 0.01. Survival did
not differ by scores.
CONCLUSIONS: As expression of both targets is variable and heterogeneous,
imaging assessment of both may yield more clinical information than either
alone. The clinical value of immunohistochemical assessment of target expression
requires prospective evaluation. Variable target expression within a patient may
contribute to treatment failure. |
Which mRNAs are sequestered in stress granules? | Stress granules are higher order assemblies of nontranslating mRNAs and proteins that form when translation initiation is inhibited.
This subset of mRNAs is characterized by extended length and adenylate-uridylate (AU)-rich motifs, is highly enriched with genes critical for cell survival and proliferation. mRNA accumulation in stress granules correlates with longer coding and UTR regions and poor translatability | Overexpression of P-glycoprotein, encoded by the MDR1 (multidrug resistance 1)
gene, is often responsible for multidrug resistance and chemotherapy failure in
cancer. We have demonstrated that, in leukaemic cells, P-glycoprotein expression
is regulated at the translational level. More recently, we have shown that in
cells overexpressing P-glycoprotein, MDR1 mRNA does not aggregate into
translationally silent stress granules. Importantly, this is not unique for
MDR1, since other transcripts encoding transmembrane proteins, and which are
thus translated at the endoplasmic reticulum, follow the same pattern. By using
a series of chimaeric transcripts, we have demonstrated that transcript
localization at the endoplasmic reticulum bypasses the signals dictating stress
granule sequestration. Polysome profile analyses and protein synthesis
experiments indicate that, upon stress withdrawal, endoplasmic-reticulum-bound
transcripts resume translation faster than those at the cytosol, which have been
sequestered into stress granules. This may represent a novel mechanism by which
drug-resistant cells respond quickly to stress, helping them to survive the
cytotoxic effect of chemotherapeutic drugs. Fused in sarcoma (FUS) belongs to the group of RNA-binding proteins implicated
as underlying factors in amyotrophic lateral sclerosis (ALS) and certain other
neurodegenerative diseases. Multiple FUS gene mutations have been linked to
hereditary forms, and aggregation of FUS protein is believed to play an
important role in pathogenesis of these diseases. In cultured cells, FUS
variants with disease-associated amino acid substitutions or short deletions
affecting nuclear localization signal (NLS) and causing cytoplasmic
mislocalization can be sequestered into stress granules (SGs). We demonstrated
that disruption of motifs responsible for RNA recognition and binding not only
prevents SG recruitment, but also dramatically increases the protein propensity
to aggregate in the cell cytoplasm with formation of juxtanuclear structures
displaying typical features of aggresomes. Functional RNA-binding domains from
TAR DNA-binding protein of 43 kDa (TDP-43) fused to highly aggregation-prone
C-terminally truncated FUS protein restored the ability to enter SGs and
prevented aggregation of the chimeric protein. Truncated FUS was also able to
trap endogenous FUS molecules in the cytoplasmic aggregates. Our data indicate
that RNA binding and recruitment to SGs protect cytoplasmic FUS from
aggregation, and loss of this protection may trigger its pathological
aggregation in vivo. Stress granules are mRNA-protein assemblies formed from nontranslating mRNAs.
Stress granules are important in the stress response and may contribute to some
degenerative diseases. Here, we describe the stress granule transcriptome
of yeast and mammalian cells through RNA-sequencing (RNA-seq) analysis of
purified stress granule cores and single-molecule fluorescence in situ
hybridization (smFISH) validation. While essentially every mRNA, and some
noncoding RNAs (ncRNAs), can be targeted to stress granules, the targeting
efficiency varies from <1% to >95%. mRNA accumulation in stress granules
correlates with longer coding and UTR regions and poor translatability.
Quantifying the RNA-seq analysis by smFISH reveals that only 10% of bulk mRNA
molecules accumulate in mammalian stress granules and that only 185 genes have
more than 50% of their mRNA molecules in stress granules. These results suggest
that stress granules may not represent a specific biological program of
messenger ribonucleoprotein (mRNP) assembly, but instead form by condensation of
nontranslating mRNPs in proportion to their length and lack of association with
ribosomes. Upon stress, cytoplasmic mRNA is sequestered to insoluble ribonucleoprotein
(RNP) granules, such as the stress granule (SG). Partially due to the belief
that translationally suppressed mRNAs are recruited to SGs in bulk,
stress-induced dynamic redistribution of mRNA has not been thoroughly
characterized. Here, we report that endoplasmic reticulum (ER) stress targets
only a small subset of translationally suppressed mRNAs into the insoluble RNP
granule fraction (RG). This subset, characterized by extended length and
adenylate-uridylate (AU)-rich motifs, is highly enriched with genes critical for
cell survival and proliferation. This pattern of RG targeting was conserved for
two other stress types, heat shock and arsenite toxicity, which induce distinct
responses in the total cytoplasmic transcriptome. Nevertheless, stress-specific
RG-targeting motifs, such as guanylate-cytidylate (GC)-rich motifs in heat
shock, were also identified. Previously underappreciated, transcriptome
profiling in the RG may contribute to understanding human diseases associated
with RNP dysfunction, such as cancer and neurodegeneration. |
Which are the problems associated with the use of PD-L1 as immunotherapy biomarker? | The use of PD-L1 (B7-H1) immunohistochemistry (IHC) as a predictive biomarker is confounded by multiple unresolved issues: variable detection antibodies, differing IHC cutoffs, tissue preparation, processing variability, primary versus metastatic biopsies, oncogenic versus induced PD-L1 expression, and staining of tumor versus immune cells | The resurgence of cancer immunotherapy stems from an improved understanding of
the tumor microenvironment. The PD-1/PD-L1 axis is of particular interest, in
light of promising data demonstrating a restoration of host immunity against
tumors, with the prospect of durable remissions. Indeed, remarkable clinical
responses have been seen in several different maligcies including, but not
limited to, melanoma, lung, kidney, and bladder cancers. Even so, determining
which patients derive benefit from PD-1/PD-L1-directed immunotherapy remains an
important clinical question, particularly in light of the autoimmune toxicity of
these agents. The use of PD-L1 (B7-H1) immunohistochemistry (IHC) as a
predictive biomarker is confounded by multiple unresolved issues: variable
detection antibodies, differing IHC cutoffs, tissue preparation, processing
variability, primary versus metastatic biopsies, oncogenic versus induced PD-L1
expression, and staining of tumor versus immune cells. Emerging data suggest
that patients whose tumors overexpress PD-L1 by IHC have improved clinical
outcomes with anti-PD-1-directed therapy, but the presence of robust responses
in some patients with low levels of expression of these markers complicates the
issue of PD-L1 as an exclusionary predictive biomarker. An improved
understanding of the host immune system and tumor microenvironment will better
elucidate which patients derive benefit from these promising agents. Programmed death 1 (PD-1, CD279) and programmed death ligand 1 (PD-L1, CD274)
are involved in generating tumor-associated immunosuppression by suppression of
T-cell proliferation and interleukin 2 (IL-2) production and immune checkpoint
inhibitors targeting these molecules are showing compelling activity against a
variety of human cancers. PD-L1 expression has shown a positive association with
response to PD-1 inhibition in noncentral nervous system (CNS) tumors, e.g.,
melanoma or non-small cell lung cancer, and is discussed as a potential
predictive biomarker for patient selection in these tumor types. This review
summarizes current knowledge and potential clinical implications of PD-L1
expression in glioblastoma. At present, the following conclusions are drawn: (a)
functional data support a role for PD-1/PD-L1 in tumor-associated
immunosuppression in glioblastoma; (b) the incidence of PD-L1-expressing
glioblastomas seems to be relatively high in comparison to other tumor types,
however, the reported rates of glioblastomas with PD-L1 protein expression vary
and range from 61 to 88%; (c) there is considerable variability in the
methodology of PD-L1 assessment in glioblastoma across studies with
heterogeneity in utilized antibodies, tissue sampling strategies,
immunohistochemical staining protocols, cut-off definitions, and evaluated
staining patterns; (d) there are conflicting data on the prognostic role and so
far no data on the predictive role of PD-L1 gene and protein expression in
glioblastoma. In summary, the ongoing clinical studies evaluating the activity
of PD-1/PD-L1 inhibitors in glioblastoma need to be complemented with well
designed and stringently executed studies to understand the influence of
PD-1/PD-L1 expression on therapy response or failure and to develop robust means
of PD-L1 assessment for meaningful biomarker development. Drugs that target the programmed cell death-1 (PD-1) receptor have shown
promising antitumor activity in clinical trials, but it is not clear whether
expression of the ligand PD-L1 is a biomarker for response. Increasingly,
researchers say that PD-L1 expression is just one of many variables that may
affect response to PD-1 blockade. Author information:
(1)Département de biologie et pathologie médicales, Gustave-Roussy, 114, rue
Edouard-Vaillant, 94805 Villejuif cedex, France; Inserm U981, Gustave-Roussy,
114, rue Edouard-Vaillant, 94805 Villejuif cedex, France. Electronic address:
[email protected].
(2)Département de biologie et pathologie médicales, Gustave-Roussy, 114, rue
Edouard-Vaillant, 94805 Villejuif cedex, France; Département de médecine,
Gustave-Roussy, 114, rue Edouard-Vaillant, 94805 Villejuif cedex, France.
(3)DITEP Gustave-Roussy, 114, rue Edouard-Vaillant, 94805 Villejuif cedex,
France; Inserm U1015, Gustave-Roussy, 114, rue Edouard-Vaillant, 94805 Villejuif
cedex, France.
(4)Inserm U981, Gustave-Roussy, 114, rue Edouard-Vaillant, 94805 Villejuif
cedex, France; DITEP Gustave-Roussy, 114, rue Edouard-Vaillant, 94805 Villejuif
cedex, France; Faculté de médecine, université Paris Saclay, 63, rue
Gabriel-Péri, 94276 Le Kremlin-Bicêtre cedex, France.
(5)Département de biologie et pathologie médicales, Gustave-Roussy, 114, rue
Edouard-Vaillant, 94805 Villejuif cedex, France; Faculté de médecine, université
Paris Saclay, 63, rue Gabriel-Péri, 94276 Le Kremlin-Bicêtre cedex, France.
(6)Département de biopathologie, MESOPATH, centre Léon-Bérard, 28, rue Laënnec,
69008 Lyon, France; Université Joseph-Fourier, Inserm U823, institut
Albert-Bonniot, Grenoble, France. CONTEXT: Although most primary cancers of the lung carry a heavy mutational load
and will potentially present many "nonself" antigens to the immune system, there
are a wide range of possible mechanisms for tumors to avoid so-called immune
surveillance. One such mechanism is the adoption of immune checkpoints to
inhibit the host immune response. Immune checkpoint inhibitors show great
promise in the treatment of advanced non-small cell lung cancer.
OBJECTIVE: To discuss the possibility of biomarker selection of patients for
these therapies. This is becoming a much debated issue, and the
immunohistochemical detection of Programmed Death Ligand 1 (PD-L1), the ligand
for the inhibitory Programmed Death receptor 1 (PD-1) checkpoint, is one
possible biomarker. Data so far available show some conflicting results, but
PD-L1 immunohistochemistry looks likely to be introduced into clinical use for
selecting patients for treatment with anti-PD-1 or anti-PD-L1 therapies. Given
that there are 4 such drugs rapidly approaching regulatory approval, each with
its own independent PD-L1 immunohistochemistry biomarker test, both oncologists
and pathologists face some significant challenges.
DATA SOURCES: Peer-reviewed literature and meeting proceedings, especially
during the last 12 months, were used.
CONCLUSIONS: The biology of PD-1/PD-L1 is complex, the clinical data for these
drugs show considerable variation, the selection performance of the PD-L1
biomarker test is not perfect, and the existence of 4 drug/test combinations
adds significantly to the problems faced. This article addresses some of the
background to this therapeutic problem and discusses some of the issues ahead. Research in cancer immunology is currently accelerating following a series of
cancer immunotherapy breakthroughs during the last 5 years. Various monoclonal
antibodies which block the interaction between checkpoint molecules PD-1 on
immune cells and PD-L1 on cancer cells have been used to successfully treat
non-small cell lung cancer (NSCLC), including some durable responses lasting
years. Two drugs, nivolumab and pembrolizumab, are now FDA approved for use in
certain patients who have failed or progressed on platinum-based or targeted
therapies while agents targeting PD-L1, atezolizumab and durvalumab, are
approaching the final stages of clinical testing. Despite impressive treatment
outcomes in a subset of patients who receive these immune therapies, many
patients with NSCLC fail to respond to anti-PD-1/PD-L1 and the identification of
a biomarker to select these patients remains highly sought after. In this
review, we discuss the recent clinical trial results of pembrolizumab,
nivolumab, and atezolizumab for NSCLC, and the significance of companion
diagnostic testing for tumor PD-L1 expression. BACKGROUND: Carcinosarcomas of the gynecologic tract, also known as maligt
mixed Müllerian tumors, are aggressive neoplasms with a high recurrence rate and
poor prognosis. Despite advances in adjuvant therapies in recent years, the
prognosis of these tumors has not improved. In fact, there are currently no
consensus guidelines for the treatment of these neoplasms and the search for
targetable biomarkers has not been successful so far. Programmed death-ligand 1
(PD-L1) has emerged as a potential target for therapeutics in a number of
maligt tumors, including melanoma, lung, and colorectal cancer. In normal
conditions, PD-L1 is thought to promote immune homeostasis via a number of
pathways, but mainly through downregulation of cytotoxic T cells. In some human
neoplasms, however, overexpression of PD-L1 by tumor cells has been observed,
which can modulate the immune system to allow cancer cells to evade host
response. As this marker could potentially be a therapeutic target for these
tumors, the immunohistochemical expression of PD-L1 in a group of
carcinosarcomas was evaluated in the present study.
MATERIAL AND METHODS: Twenty-nine cases of gynecologic carcinosarcomas were
analyzed, corresponding to tumors originating from the uterus (25), ovary (2),
fallopian tube (1), and pelvic epithelium (1). Immunohistochemistry for PD-L1
was performed on paraffin sections and the staining results were assessed
semiquantitatively in both epithelial and mesenchymal components of each tumor.
RESULTS: Positive membranous staining for PD-L1 was detected in 25/29 tumors
(86%). The epithelial components were strongly positive in 19/29 (65%) and
weakly positive in 6/29 tumors (21%). The mesenchymal elements were strongly
positive in 8/29 (27%) and weakly positive in 3/29 tumors (10%). With exception
of 1, all tumors with positive sarcomatous components had staining of the
carcinomatous element. Four tumors were negative for PD-L1 in both components.
CONCLUSIONS: This study shows that PD-L1 is expressed by the majority of
carcinosarcomas, predomitly in the epithelial components. This is
particularly important as most locoregional recurrences and distant metastases
are of epithelial origin. This finding may serve as a basis for possible
therapeutic approaches using antibodies that have already shown significant
value in a number of other maligt tumors. AIM: The treatment of non-small-cell lung cancer has changed after the
development of the immune checkpoint inhibitors. Although the most studied
biomarker is PD-L1 expression, its clinical significance is still debatable. In
this article, we show the updated survival analysis of all published data.
METHODS: We searched in network and conference data sources for relevant
clinical studies of immunotherapy for non-small-cell lung cancer that assessed
the PD-L1 expression even as an exploratory analysis. The updated survival
hazard ratios (HR) were included in the analysis.
RESULTS: 14 studies with 2857 patients were included (2019 treated with
immunotherapy). The response rate was as higher among PD-L1-positive patients
(RR: 2.19, 95% CI: 1.63-2.94). PD-L1 expression was also related to better
progression-free survival (HR: 0.69, 95% CI: 0.57-0.85) and better overall
survival (HR: 0.77, 95% CI: 0.67-0.89).
CONCLUSION: PD-L1 overexpression predicts activity as well as better survival
for patients treated with immune checkpoint inhibitors. Neuroendocrine neoplasms (NENs) are rare, heterogeneous and ubiquitous tumors
commonly localized in the gastrointestinal tract, lung, and pancreas. The
clinical behavior of NEN is highly unpredictable; in fact, low-grade cases can
unexpectedly be associated with metastases. Currently, the 2010 WHO NEN
classification employs histological differentiation and the proliferation index
for grading tumors but fails to provide reliable prognostic and therapeutic
indications. Therefore, there is an urgent need for a better characterization of
G2/G3 NENs. Similar to several other tumors, NENs possess immune-escape
mechanisms, but very little has yet been done to characterize this crucial
aspect. There are no available data describing PD-L1 expression in these tumors.
Here we provide, for the first time, evidence of PD-L1 tissue expression in
gastroenteropancreatic neuroendocrine neoplasms (GEP-NENs). PD-L1 expression was
significantly associated with a high-grade WHO classification (G3) (P<0.001) but
not with gender, primary site, or lymph node status. The PD-L1 positivity rate
and signal intensity are directly correlated (P<0.001) with a grade increase
from G1 to G3. In particular in G3 cases, we observed a dichotomy between the
morphology (WD- and PD-NENs) and Ki67. Moreover, our study demonstrated a
significant association with the grade and PD-L1 expression levels in
immune-infiltrating cells (P<0.001). In particular, G3 tumors are characterized
by strong PD-L1 expression in both the tumor and infiltrating immune cells
(P<0.001), reflecting an unfavorable environment for T-cell-mediated tumor
aggression. These findings suggest that NENs might acquire resistance to immune
surveillance by upregulating PD-L1 and inhibiting peritumoral and intratumoral
infiltrating lymphocytes. Here we demonstrate that PD-L1 is currently the
best-known biomarker for G3 NENs, becoming the new gold standard for G3 NEN
discrimination. Furthermore, pharmacological approaches using anti-PD-1
antibodies may become the logical choice for the treatment of G3 cases with a
poor prognosis. BACKGROUND: The PD-1 receptor and its ligands PD-L1 and PD-L2 are known to be
significantly involved in T-cell regulation. Recent studies suggest that PD-L1
expression in maligt tumors contributes to an immunosuppressive
microenvironment and disruption of antitumoral immune response. Drugs targeting
this pathway are already tested in clinical trials against several tumor
entities with promising results. However, until now comprehensive data with
regard to PD-L1 and PD-L2 expression in head and neck squamous cell carcinoma
(HNSCC) is still lacking.
PATIENTS AND METHODS: We assessed PD-L1 and PD-L2 expression via
immunohistochemistry in two independent cohorts of 293 HNSCC patients.
RESULTS: A significant subset of HNSCC showed high expression levels of PD-L1.
Most remarkable, we detected a strong correlation between PD-L1 expression and
overall survival time in both HNSCC cohorts. Further, in multivariate cox
proportional hazard models, PD-L1 dominates as the strongest prognostic factor
of patient's outcome in HNSCC, leaving even tumor stage and distant metastasis
behind. Moreover, strong PD-L1 expression was associated with the presence of
distant metastases in a subset of cases.
CONCLUSIONS: In summary, while the significance of PD-L2 in HNSCC seems to
minor, we show that PD-L1 expression is common in HNSCC and, more importantly, a
both robust and strong prognostic biomarker. In this respect, our results
provide hints on further application of therapies targeting the PD-1/PD-L1
pathway in HNSCC. Investigation of response and outcome of patients receiving
anti-PD-1/PD-L1 containing therapies in correlation with PD-L1 expression
analysis should be an important task for the future.
STATEMENT OF TRANSLATIONAL RELEVANCE: In spite of improved treatment options and
increasing knowledge of molecular alterations in HNSCC, the survival rate has
not been dramatically changed in the past decades. Pies are missing in HNSCC.
One promising candidate in cancer immune therapy is PD-L1. Drugs targeting PD-L1
or its receptor PD-1 are subject of several clinical studies in different cancer
entities. However, comprehensive data about PD-L1 expression in HNSCC and
therefore a rational basis for anti PD-L1/PD-1 therapy in HNSCC is lacking.
Here, we provide wide-ranging data about PD-L1 expression in HNSCC of all major
localizations. We observed a strong correlation between expression of PD-L1 and
reduced overall survival time. Furthermore, high PD-L1 expression was identified
as a strong prognostic factor of patient's outcome when verified together with
recognized prognostic factors. Triple negative breast cancer (TNBC) has an aggressive clinical behaviour, with
a poorer prognosis compared to other subtypes. Recently, tumor-infiltrating
lymphocytes (TILs) have been proposed as a predictive biomarker for a better
clinical outcome and pathological response (pR) after neoadjuvant chemotherapy
(NACT) in TNBC. These data confirm the role of the immune system in the
neoplastic progression and in the response to therapy. We performed a
retrospective analysis of 54 pre-NACT biopsies of TNBC and compared both the
percentage of stromal TILs and the degree of PD-L1 expression with the extent of
pR to standard NACT. A pathological complete response (pCR) was achieved in 35%
of cases. Univariate analysis showed (i) a significant association between PD-L1
expression in ≥25% of neoplastic cells and the achievement of a pCR (p = 0.024);
(ii) a significantly higher frequency of pCR in cases showing ≥50% stromal TILs
(p < 0.001). However in the multivariate analysis only PD-L1 expression on tumor
cells remained significantly associated with pCR (OR = 1,13; 95% CI 1,01-1,27),
suggesting that the expression of this biomarker could be associated with a
subpopulation of TNBC more likely to respond to chemotherapy. These data need to
be confirmed by larger studies. BACKGROUND: Lung cancer is the most common cause of cancer-related death among
males and the second leading cause among females globally. Checkpoint inhibitors
re-engage the immune system to fight cancer. This review evaluates phase III
data on the use of checkpoint inhibitors in the treatment of advanced NSCLC and
addresses PD-L1 expression in predicting efficacy.
METHODS: Six phase III clinical trials investigating checkpoint inhibitors for
NSCLC were identified through a search of PubMed (to November 15, 2016) and
conference databases, with findings updated from a directed search of eligible
studies conducted in January 2018.
RESULTS: Significant reductions in the risk of death ranging from 27% to 41% and
were observed second-line and beyond. A relationship between PD-L1 expression
and survival was apparent in most trials with optimal benefit for the highest
expression levels (≥50%). Benefit was also observed at low or no PD-L1
expression levels and in third-line in some studies. Significantly improved PFS
was observed for pembrolizumab at high PD-L1 expression levels (≥50%)
first-line. Immune-related adverse events associated with checkpoint inhibitors
are tolerable and rates of pneumonitis may be lower among PD-L1 inhibitors. Use
of checkpoint inhibitors for tumors with driver mutations should only be
considered after all appropriate targeted therapy and chemotherapy have been
exhausted. PD-L1 testing presents a valuable tool to guide treatment sequencing
and we recommend use of agent-specific PD-L1 tests and respective scoring
systems until a standardized, convenient and broadly applicable test is
identified.
CONCLUSIONS: Checkpoint inhibitors represent a major advance in the treatment of
advanced NSCLC and PD-L1 status can inform treatment decisions. Gastric adenocarcinoma and esophageal adenocarcinoma are aggressive cancers with
a poor prognosis. Therefore, new therapeutic strategies are needed, especially
for patients refractory to conventional treatment. Cancer immunotherapy (CIT),
is a promising new treatment option and is effective in a proportion of patients
with gastroesophageal maligcies. Biomarkers for selecting patients likely to
benefit from CIT in gastroesophageal maligcies remain unproven. Programmed
cell death ligand-1 (PD-L1), which is a validated biomarker in non-small cell
lung cancer (NSCLC), is often also used to select patients for CIT in the
context of gastroesophageal cancer, although this marker has not been validated
for this purpose. We question the use of PD-L1 as a biomarker in
gastroesophageal cancers, as there are fundamental differences in PD-L1
expression between NSCLC and gastroesophageal cancers. This review discusses the
value of PD-L1 in selecting patients for CIT in esophageal and gastric cancer.
Potential alternatives, especially microsatellite instability and Epstein-Barr
virus positivity, are discussed. Author information:
(1)Grupo de Enfermedades Respiratorias, Servicio de Neumología, Hospital
Universitario La Paz-IdiPAZ, Madrid, Spain.
(2)Centro de Investigación Biomédica en Red en Enfermedades Respiratorias
(CIBERES), Madrid, Spain.
(3)Respiratory Dept, Hospital Universitario y Politécnico la Fe, Valencia,
Spain.
(4)Respiratory Dept, Hospital Universitario de Valme, Seville, Spain.
(5)Respiratory Dept, Group of Translational Research in Respiratory Medicine,
Hospital Universitari Arnau de Vilanova and Santa Maria, IRBLleida, Lleida,
Spain.
(6)Dermatology Dept, Instituto Valenciano de Oncología, Valencia, Spain.
(7)Dermatology Dept, Hospital de Manises, Valencia, Spain.
(8)Respiratory Dept, ISABIAL, Hospital General Universitario de Alicante,
Alicante, Spain.
(9)Departamento Medicina Clinica, Universidad Miguel Herdez, Elche, Spain.
(10)Respiratory Dept, Hospital san Juan de Alicante, Alicante, Spain.
(11)Respiratory Dept, Hospital Germans Trias i Pujol, Centro de investigacion
Biomedica, Madrid, Spain.
(12)Respiratory Dept, Hospital Clinic (IDIBAPS), Barcelona, Spain.
(13)Respiratory Dept, Hospital Universitario Cruces, Bilbao, Spain.
(14)Respiratory Dept, Hospital Universitario de Getafe, Madrid, Spain.
(15)Respiratory Dept, Hospital Universitario S. Pedro Alcántara, Cáceres, Spain.
(16)Respiratory Dept, Hospital 12 de Octubre, Madrid, Spain.
(17)Respiratory Dept, Hospital Universitario de Guadalajara, Guadalajara, Spain.
(18)Pneumology Dept, Hospital Consorcio Terrassa, Barcelona, Spain.
(19)Dermatology Dept, Hospital de la Santa Creu i Sant Pau, Barcelona, Spain.
(20)Unitat de Biofísica i Bioenginyeria, Facultat de Medicina i Ciències de la
Salut, Universitat de Barcelona, Barcelona, Spain.
(21)Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS),
Barcelona, Spain.
(22)TumorImmunology Laboratory IdiPAZ, Madrid, Spain.
(23)Innate Immune Response Group, IdiPAZ, Madrid, Spain.
(24)Dept of Child Health, University of Missouri School of Medicine, Columbia,
MO, USA.
(25)Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, Spain. |
Is poliosis circumscripta another term for a white or unpigmented patch of hair or skin? | Yes. Poliosis circumscripta is another term for a white or unpigmented patch of hair or skin. | |
How are SAHFS created? | Cellular senescence-associated heterochromatic foci (SAHFS) are a novel type of chromatin condensation involving alterations of linker histone H1 and linker DNA-binding proteins. SAHFS can be formed by a variety of cell types, but their mechanism of action remains unclear. | Cellular senescence is characterized by stable cell cycle arrest that is
triggered by various forms of stress stimuli. Senescent cells show a series of
morphological and physiological alterations including a flat and enlarged
morphology, an increase in acidic beta-galactosidase activity, chromatin
condensation, and changes in gene expression pattern. These features are not
observed in proliferating cells or quiescent cells in vitro. Using these
senescence markers, cellular senescence has been shown to occur in benign or
premaligt lesions but not in maligt lesions and to act as a
tumor-suppressing mechanism in vivo. The onset and maintece of the senescent
state are regulated by two tumor suppressor proteins, p53 and Rb, which mediate
senescence signals through p38 mitogen-activated protein kinase and
cyclin-dependent kinase inhibitors. Alterations of chromatin structure are
believed to contribute to the irreversible nature of the senescent state.
Senescent cells form characteristic heterochromatin structure called
senescence-associated heterochromatic foci (SAHFs), which may repress the
expression of proliferation-promoting genes, such as E2F target genes. Recent
studies have provided molecular insights into the structure and the mechanism of
SAHF formation. In this paper, we review the role of cellular senescence in
tumor suppression in vivo and the molecular mechanism of stable growth arrest in
senescent cells, focusing on the special form of heterochromatin, SAHFs. It is almost ten years since senescence associated heterochromatic foci (SAHFs)
were first described in human diploid fibroblasts (HDFs). Since then, a number
of factors have been identified that affect SAHF formation, including HMGA
proteins, structural components of SAHFs. However, the involvement of epigenetic
marks in SAHF formation remains unclear. Our recent study, combining microscopy
and ChIP-seq approaches, revealed that SAHFs are formed through spatial
repositioning of the genome. This occurs according to certain chromatin features
that are correlated with, but do not require, the repressive marks histone H3
trimethylated on lysine 9 (H3K9me3) and H3K27me3. These repressive marks are
segregated from each other within SAHFs, forming layered high-order chromatin
structures (HOCS). During the dynamic change in HOCS as SAHFs form, the linear
epigenomic profiles of these repressive marks are highly static. This is in
marked contrast to the spreading of repressive marks occurring during embryonic
cell differentiation. Thus the layered HOCS of SAHFs is likely achieved mainly
through the spatial rearrangement of pre-existing heterochromatin, rather than
spreading of heterochromatin. Evidence for the co-association of similar types
of chromatin is emerging and SAHFs may provide a unique model system to study
the correlation between HOCS and chromatin types, which are readily visible and
regulable. Studies in primary and tumor cells suggest that MYC plays an important role in
regulating cellular senescence, thereby impacting on tumor development. Here we
describe different common methods to measure senescence in cell cultures and in
tissues. These include measurement of senescence-associated β-galactosidase
activity (SA-β-gal), senescence-associated heterochromatin foci (SAHFs),
proliferative arrest, morphological changes, and expression and activity of
proteins involved in the senescence process, such as p53 and Rb pathway proteins
and secretory proteins. It is important to note that there is no unique marker
that unambiguously defines a senescent state, and it is therefore necessary to
combine measurements of several different markers that together determine
whether cells are senescent or not. Measurement of senescence is an important
aspect of studies of MYC biology and will improve our understanding of MYC
function and regulation both in preclinical and clinical settings. This may form
the basis for new concepts of pro-senescence therapy to combat MYC in cancer. |
What is another name for AZD0530? | AZD0530 is also known as saracatinib. | Src is a nonreceptor tyrosine kinase involved in the cross-talk and mediation of
many signaling pathways that promote cell proliferation, adhesion, invasion,
migration, and tumorigenesis. Increased Src activity has been reported in many
types of human cancer, including gastric cancer. Therefore, this factor has been
identified as a promising therapeutic target for cancer treatments, and
targeting Src in gastric cancer is predicted to have potent effects. We
evaluated the antitumor effect of a c-Src/Abl kinase inhibitor, saracatinib
(AZD0530), alone or combined with chemotherapeutic agents in gastric cancer cell
lines and a NCI-N87 xenograft model. Among 10 gastric cancer cell lines,
saracatinib specifically inhibited the growth and migration/invasion of SNU216
and NCI-N87 cells. Saracatinib blocked the Src/FAK, HER family, and oncogenic
signaling pathways, and it induced G(1) arrest and apoptosis in SNU216 and
NCI-N87 cells. Apoptosis required induction of the proapoptotic BCL2 family
member Bim. Knockdown of Bim using siRNA decreased apoptosis induced by
treatment with saracatinib, suggesting that Bim has an important role in
saracatinib-induced apoptosis. Saracatinib enhanced the effects of lapatinib, an
EGFR/HER2 dual inhibitor, in SNU216 and NCI-N87 cells. Furthermore, combined
treatment with saracatinib and 5-fluorouracil (5-FU) or cisplatin exerted
synergistic effects in both saracatinib-sensitive and saracatinib-resistant
cells. Consistent with our in vitro findings, cotreatment with saracatinib and
5-FU resulted in enhanced antitumor activity in the NCI-N87 xenografts. These
data indicate that the inhibition of Src kinase activity by saracatinib alone or
in combination with other agents can be a strategy to target gastric cancer. |
Which is the effect of the HP1a protein on chromatin? | Heterochromatin Protein 1 (HP1a) is a well-known conserved protein that is involved in heterochromatin formation and gene silencing through the reading of the heterochromatin mark methylation of histone H3 lysine 9 (H3K9me) in different species including humans. | The interface between cellular systems involving small noncoding RNAs and
epigenetic change remains largely unexplored in metazoans. RNA-induced silencing
systems have the potential to target particular regions of the genome for
epigenetic change by locating specific sequences and recruiting chromatin
modifiers. Noting that several genes encoding RNA silencing components have been
implicated in epigenetic regulation in Drosophila, we sought a direct link
between the RNA silencing system and heterochromatin components. Here we show
that PIWI, an ARGONAUTE/PIWI protein family member that binds to
Piwi-interacting RNAs (piRNAs), strongly and specifically interacts with
heterochromatin protein 1a (HP1a), a central player in heterochromatic gene
silencing. The HP1a dimer binds a PxVxL-type motif in the N-terminal domain of
PIWI. This motif is required in fruit flies for normal silencing of transgenes
embedded in heterochromatin. We also demonstrate that PIWI, like HP1a, is itself
a chromatin-associated protein whose distribution in polytene chromosomes
overlaps with HP1a and appears to be RNA dependent. These findings implicate a
direct interaction between the PIWI-mediated small RNA mechanism and
heterochromatin-forming pathways in determining the epigenetic state of the fly
genome. Heterochromatin Protein 1 (HP1a) is a well-known conserved protein involved in
heterochromatin formation and gene silencing in different species including
humans. A general model has been proposed for heterochromatin formation and
epigenetic gene silencing in different species that implies an essential role
for HP1a. According to the model, histone methyltransferase enzymes (HMTases)
methylate the histone H3 at lysine 9 (H3K9me), creating selective binding sites
for itself and the chromodomain of HP1a. This complex is thought to form a
higher order chromatin state that represses gene activity. It has also been
found that HP1a plays a role in telomere capping. Surprisingly, recent studies
have shown that HP1a is present at many euchromatic sites along polytene
chromosomes of Drosophila melanogaster, including the developmental and
heat-shock-induced puffs, and that this protein can be removed from these sites
by in vivo RNase treatment, thus suggesting an association of HP1a with the
transcripts of many active genes. To test this suggestion, we performed an
extensive screening by RIP-chip assay (RNA-immunoprecipitation on microarrays),
and we found that HP1a is associated with transcripts of more than one hundred
euchromatic genes. An expression analysis in HP1a mutants shows that HP1a is
required for positive regulation of these genes. Cytogenetic and molecular
assays show that HP1a also interacts with the well known proteins DDP1, HRB87F,
and PEP, which belong to different classes of heterogeneous nuclear
ribonucleoproteins (hnRNPs) involved in RNA processing. Surprisingly, we found
that all these hnRNP proteins also bind heterochromatin and are domit
suppressors of position effect variegation. Together, our data show novel and
unexpected functions for HP1a and hnRNPs proteins. All these proteins are in
fact involved both in RNA transcript processing and in heterochromatin
formation. This suggests that, in general, similar epigenetic mechanisms have a
significant role on both RNA and heterochromatin metabolisms. The eyegone (eyg) gene encodes Eyg, a transcription factor of the Pax family
with multiple roles during Drosophila development. Although Eyg has been shown
to act as a repressor, nothing is known about the mechanism by which it
represses its target genes. Here, we show that Eyg forms a protein complex with
heterochromatin protein 1a (HP1a). Both proteins bind to the same chromatin
regions on polytene chromosomes and act cooperatively to suppress variegation
and mediate gene silencing. In addition, Eyg binds to a wingless (wg) enhancer
region, recruiting HP1a to assemble a closed, heterochromatin-like conformation
that represses transcription of the wg gene. We describe here the evidence that
suggests that Eyg, encoded by eyegone (eyg), represses wingless (wg) during eye
development by association with HP1a. We show that Eyg forms a protein complex
with HP1a and both proteins colocalize on salivary gland polytene chromosomes.
Using position effect variegation (PEV) experiments, we demonstrated that eyg
has a dose-dependent effect on heterochromatin gene silencing and identified a
genetic interaction with HP1a in this process. We further demonstrated that HP1a
binds to the same wg enhancer element as Eyg. DNase I sensitivity assays
indicated that this enhancer region has a closed heterochromatin-like
conformation, which becomes open in eyg mutants. In these mutants, much less
HP1a binds to the wg enhancer region, as shown by ChIP experiments. Furthermore,
as previously described for Eyg, a reduction in the amount of HP1a in the eye
imaginal disc derepresses wg. Together, our results suggest a model in which Eyg
specifically binds to the wg enhancer region, recruiting HP1a to that site. The
recruitment of HP1a prevents transcription by favoring a closed,
heterochromatin-like structure. Thus, for the first time, we show that HP1a
plays a direct role in the repression of a developmentally regulated gene, wg,
during Drosophila eye development. The KDM4 subfamily of JmjC domain-containing demethylases mediates demethylation
of histone H3K36me3/me2 and H3K9me3/me2. Several studies have shown that human
and yeast KDM4 proteins bind to specific gene promoters and regulate gene
expression. However, the genome-wide distribution of KDM4 proteins and the
mechanism of genomic-targeting remain elusive. We have previously identified
Drosophila KDM4A (dKDM4A) as a histone H3K36me3 demethylase that directly
interacts with HP1a. Here, we performed H3K36me3 ChIP-chip analysis in wild type
and dkdm4a mutant embryos to identify genes regulated by dKDM4A demethylase
activity in vivo. A subset of heterochromatic genes that show increased H3K36me3
levels in dkdm4a mutant embryos overlap with HP1a target genes. More
importantly, binding to HP1a is required for dKDM4A-mediated H3K36me3
demethylation at a subset of heterochromatic genes. Collectively, these results
show that HP1a functions to target the H3K36 demethylase dKDM4A to
heterochromatic genes in Drosophila. Chromatin environments differ greatly within a eukaryotic genome, depending on
expression state, chromosomal location, and nuclear position. In genomic regions
characterized by high repeat content and high gene density, chromatin structure
must silence transposable elements but permit expression of embedded genes. We
have investigated one such region, chromosome 4 of Drosophila melanogaster.
Using chromatin-immunoprecipitation followed by microarray (ChIP-chip) analysis,
we examined enrichment patterns of 20 histone modifications and 25 chromosomal
proteins in S2 and BG3 cells, as well as the changes in several marks resulting
from mutations in key proteins. Active genes on chromosome 4 are distinct from
those in euchromatin or pericentric heterochromatin: while there is a depletion
of silencing marks at the transcription start sites (TSSs), HP1a and H3K9me3,
but not H3K9me2, are enriched strongly over gene bodies. Intriguingly, genes on
chromosome 4 are less frequently associated with paused polymerase. However,
when the chromatin is altered by depleting HP1a or POF, the RNA pol II
enrichment patterns of many chromosome 4 genes shift, showing a significant
decrease over gene bodies but not at TSSs, accompanied by lower expression of
those genes. Chromosome 4 genes have a low incidence of TRL/GAGA factor binding
sites and a low T(m) downstream of the TSS, characteristics that could
contribute to a low incidence of RNA polymerase pausing. Our data also indicate
that EGG and POF jointly regulate H3K9 methylation and promote HP1a binding over
gene bodies, while HP1a targeting and H3K9 methylation are maintained at the
repeats by an independent mechanism. The HP1a-enriched, POF-associated chromatin
structure over the gene bodies may represent one type of adaptation for genes
embedded in repetitive DNA. Heterochromatin protein 1 (HP1a in Drosophila) is a conserved eukaryotic
chromosomal protein that is prominently associated with pericentric
heterochromatin and mediates the concomitant gene silencing. Mechanistic studies
implicate HP1 family proteins as 'hub proteins,' able to interact with a variety
of chromosomal proteins through the chromo-shadow domain (CSD), as well as to
recognize key histone modification sites [primarily histone H3 di/trimethyl Lys9
(H3K9me2/3)] through the chromodomain (CD). Consequently, HP1 has many important
roles in chromatin architecture and impacts both gene expression and gene
silencing, utilizing a variety of mechanisms. Clearly, HP1 function is altered
by context, and potentially by post-translational modifications (PTMs). Here, we
report on recent ideas as to how this versatile protein accomplishes its diverse
functions. Heterochromatin protein 1 (HP1a) has conserved roles in gene silencing and
heterochromatin and is also implicated in transcription, DNA replication, and
repair. Here we identify chromatin-associated protein and RNA interactions of
HP1a by BioTAP-XL mass spectrometry and sequencing from Drosophila S2 cells,
embryos, larvae, and adults. Our results reveal an extensive list of known and
novel HP1a-interacting proteins, of which we selected three for validation. A
strong novel interactor, dADD1 (Drosophila ADD1) (CG8290), is highly enriched in
heterochromatin, harbors an ADD domain similar to human ATRX, displays selective
binding to H3K9me2 and H3K9me3, and is a classic genetic suppressor of
position-effect variegation. Unexpectedly, a second hit, HIPP1 (HP1 and
insulator partner protein-1) (CG3680), is strongly connected to CP190-related
complexes localized at putative insulator sequences throughout the genome in
addition to its colocalization with HP1a in heterochromatin. A third interactor,
the histone methyltransferase MES-4, is also enriched in heterochromatin. In
addition to these protein-protein interactions, we found that HP1a selectively
associated with a broad set of RNAs transcribed from repetitive regions. We
propose that this rich network of previously undiscovered interactions will
define how HP1a complexes perform their diverse functions in cells and
developing organisms. In eukaryotic cells, the organization of genomic DNA into chromatin regulates
many biological processes, from the control of gene expression to the regulation
of chromosome segregation. The proper maintece of this structure upon cell
division is therefore of prime importance during development for the maintece
of cell identity and genome stability. The chromatin assembly factor 1 (CAF-1)
is involved in the assembly of H3-H4 histone dimers on newly synthesized DNA and
in the maintece of a higher order structure, the heterochromatin, through an
interaction of its large subunit with the heterochromatin protein HP1a. We
identify here a conserved domain in the large subunit of the CAF-1 complex
required for its interaction with HP1a in the Drosophila fruit fly. Functional
analysis reveals that this domain is dispensable for viability but participates
in two processes involving heterochromatin: position-effect variegation and long
range chromosomal interactions during meiotic prophase. Importantly, the
identification in the large subunit of CAF-1 of a domain required for its
interaction with HP1 allows the separation of its functions in
heterochromatin-related processes from its function in the assembly of H3-H4
dimers onto newly synthesized DNA. |
Is Selumetinib effective for low-grade glioma? | Selumetinib has promising antitumor activity in children with LGG. | BACKGROUND: Activation of the mitogen-activated protein kinase pathway is
important for growth of pediatric low-grade gliomas (LGGs). The aim of this
study was to determine the recommended phase II dose (RP2D) and the
dose-limiting toxicities (DLTs) of the MEK inhibitor selumetinib in children
with progressive LGG.
METHODS: Selumetinib was administered orally starting at 33 mg/m2/dose b.i.d.,
using the modified continual reassessment method. Pharmacokinetic analysis was
performed during the first course. BRAF aberrations in tumor tissue were
determined by real-time polymerase chain reaction and fluorescence in situ
hybridization.
RESULTS: Thirty-eight eligible subjects were enrolled. Dose levels 1 and 2 (33
and 43 mg/m2/dose b.i.d.) were excessively toxic. DLTs included grade 3 elevated
amylase/lipase (n = 1), headache (n = 1), mucositis (n = 2), and grades 2-3 rash
(n = 6). At dose level 0 (25 mg/m2/dose b.i.d, the RP2D), only 3 of 24 subjects
experienced DLTs (elevated amylase/lipase, rash, and mucositis). At the R2PD,
the median (range) area under the curve (AUC0-∞) and apparent oral clearance of
selumetinib were 3855 ng*h/mL (1780 to 7250 ng × h/mL) and 6.5 L × h-1 × m-2
(3.4 to 14.0 L × h-1 × m-2), respectively. Thirteen of 19 tumors had BRAF
abnormalities. Among the 5 (20%) of 25 subjects with sustained partial
responses, all at the RP2D, 4 had BRAF aberrations, 1 had insufficient tissue.
Subjects received a median of 13 cycles (range: 1-26). Fourteen (37%) completed
all protocol treatment (26 cycles [n = 13], 13 cycles [n = 1]) with at least
stable disease; 2-year progression-free survival at the RP2D was 69 ± SE 9.8%.
CONCLUSION: Selumetinib has promising antitumor activity in children with LGG.
Rash and mucositis were the most common DLTs. BACKGROUND: Paediatric low-grade glioma is the most common CNS tumour of
childhood. Although overall survival is good, disease often recurs. No single
universally accepted treatment exists for these patients; however, standard
cytotoxic chemotherapies are generally used. We aimed to assess the activity of
selumetinib, a MEK1/2 inhibitor, in these patients.
METHODS: The Pediatric Brain Tumor Consortium performed a multicentre, phase 2
study in patients with paediatric low-grade glioma in 11 hospitals in the USA.
Patients aged 3-21 years with a Lansky or Karnofsky performance score greater
than 60 and the presence of recurrent, refractory, or progressive paediatric
low-grade glioma after at least one standard therapy were eligible for
inclusion. Patients were assigned to six unique strata according to histology,
tumour location, NF1 status, and BRAF aberration status; herein, we report the
results of strata 1 and 3. Stratum 1 comprised patients with WHO grade I
pilocytic astrocytoma harbouring either one of the two most common BRAF
aberrations (KIAA1549-BRAF fusion or the BRAFV600E [Val600Glu] mutation).
Stratum 3 comprised patients with any neurofibromatosis type 1 (NF1)-associated
paediatric low-grade glioma (WHO grades I and II). Selumetinib was provided as
capsules given orally at the recommended phase 2 dose of 25 mg/m2 twice daily in
28-day courses for up to 26 courses. The primary endpoint was the proportion of
patients with a stratum-specific objective response (partial response or
complete response), as assessed by the local site and sustained for at least 8
weeks. All responses were reviewed centrally. All eligible patients who
initiated treatment were evaluable for the activity and toxicity analyses.
Although the trial is ongoing in other strata, enrolment and planned follow-up
is complete for strata 1 and 3. This trial is registered with
ClinicalTrials.gov, number NCT01089101.
FINDINGS: Between July 25, 2013, and June 12, 2015, 25 eligible and evaluable
patients were accrued to stratum 1, and between Aug 28, 2013, and June 25, 2015,
25 eligible and evaluable patients were accrued to stratum 3. In stratum 1, nine
(36% [95% CI 18-57]) of 25 patients achieved a sustained partial response. The
median follow-up for the 11 patients who had not had a progression event by Aug
9, 2018, was 36·40 months (IQR 21·72-45·59). In stratum 3, ten (40% [21-61]) of
25 patients achieved a sustained partial response; median follow-up was 48·60
months (IQR 39·14-51·31) for the 17 patients without a progression event by Aug
9, 2018. The most frequent grade 3 or worse adverse events were elevated
creatine phosphokinase (five [10%]) and maculopapular rash (five [10%]). No
treatment-realted deaths were reported.
INTERPRETATION: Selumetinib is active in recurrent, refractory, or progressive
pilocytic astrocytoma harbouring common BRAF aberrations and NF1-associated
paediatric low-grade glioma. These results show that selumetinib could be an
alternative to standard chemotherapy for these subgroups of patients, and have
directly led to the development of two Children's Oncology Group phase 3 studies
comparing standard chemotherapy to selumetinib in patients with newly diagnosed
paediatric low-grade glioma both with and without NF1.
FUNDING: National Cancer Institute Cancer Therapy Evaluation Program, the
American Lebanese Syrian Associated Charities, and AstraZeneca. |
What is Nextflow? | Reproducing routine bioinformatics analysis is challenging owing to a combination of factors hard to control for. Nextflow is a flow management framework that uses container technology to insure efficient deployment and reproducibility of computational analysis pipelines. Third party pipelines can be ported into Nextflow with minimum re-coding. | Reproducing routine bioinformatics analysis is challenging owing to a
combination of factors hard to control for. Nextflow is a flow management
framework that uses container technology to insure efficient deployment and
reproducibility of computational analysis pipelines. Third party pipelines can
be ported into Nextflow with minimum re-coding. We used RNA-Seq quantification,
genome annotation and phylogeny reconstruction examples to show how two
seemingly irreproducible analyzes can be made stable across platforms when
ported into Nextflow. |
Which application is the backbone of BioPAXViz? | BioPAXViz is a Cytoscape (version 3) application, providing a comprehensive framework for metabolic pathway visualization. Beyond the basic parsing, viewing and browsing roles, the main novel function that BioPAZViz provides is a visual comparative analysis of metabolic pathway topologies across pre-computed pathway phylogenomic profiles given a species phylogeny. | SUMMARY: BioPAXViz is a Cytoscape (version 3) application, providing a
comprehensive framework for metabolic pathway visualization. Beyond the basic
parsing, viewing and browsing roles, the main novel function that BioPAXViz
provides is a visual comparative analysis of metabolic pathway topologies across
pre-computed pathway phylogenomic profiles given a species phylogeny.
Furthermore, BioPAXViz supports the display of hierarchical trees that allow
efficient navigation through sets of variants of a single reference pathway.
Thus, BioPAXViz can significantly facilitate, and contribute to, the study of
metabolic pathway evolution and engineering.
AVAILABILITY AND IMPLEMENTATION: BioPAXViz has been developed as a Cytoscape app
and is available at: https://github.com/CGU-CERTH/BioPAX.Viz. The software is
distributed under the MIT License and is accompanied by example files and data.
Additional documentation is available at the aforementioned GitHub repository.
CONTACT: [email protected]. |
What is SpatialDE? | SpatialDE is a statistical test to identify genes with spatial patterns of expression variation from multiplexed imaging or spatial RNA-sequencing data. SpatialDE also implements ' automatic expression histology', a spatial gene-clustering approach that enables expression-based tissue histology. | Technological advances have made it possible to measure spatially resolved gene
expression at high throughput. However, methods to analyze these data are not
established. Here we describe SpatialDE, a statistical test to identify genes
with spatial patterns of expression variation from multiplexed imaging or
spatial RNA-sequencing data. SpatialDE also implements 'automatic expression
histology', a spatial gene-clustering approach that enables expression-based
tissue histology. |
What is the Match BAM to VCF method? | MBV (Match BAM to VCF) is a method to quickly solve sample mislabeling and detect cross-sample contamination and PCR amplification bias. | MOTIVATION: Large genomic datasets combining genotype and sequence data, such as
for expression quantitative trait loci (eQTL) detection, require perfect
matching between both data types.
RESULTS: We described here MBV (Match BAM to VCF); a method to quickly solve
sample mislabeling and detect cross-sample contamination and PCR amplification
bias.
AVAILABILITY AND IMPLEMENTATION: MBV is implemented in C ++ as an independent
component of the QTLtools software package, the binary and source codes are
freely available at https://qtltools.github.io/qtltools/ .
CONTACT: [email protected] or [email protected].
SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics
online. |
Describe MAGNIMS criteria. | Magnetic Resonance Imaging in Multiple Sclerosis (MAGNIMS) network proposed modifications to the MRI criteria to define dissemination in space (DIS) and time (DIT) for the diagnosis of multiple sclerosis in patients with clinically isolated syndrome (CIS). | In patients who present with a clinically isolated syndrome (CIS), whose
features are suggestive of multiple sclerosis (MS), fulfilling McDonald 2010
magnetic resoce imaging (MRI) criteria for dissemination in space (DIS) and
dissemination in time (DIT) enables a diagnosis of MS. While ⩾1 periventricular
lesion is included in the 2010 DIS criteria, earlier McDonald criteria required
⩾3 periventricular lesions to confirm DIS and recent Magnetic Resoce Imaging
in Multiple Sclerosis (MAGNIMS)-recommended DIS criteria also require ⩾3
lesions. We investigated the effect of varying the required number of
periventricular lesions and found that the best combination of specificity and
sensitivity for clinically definite MS was seen for ⩾1 periventricular lesion
using both the McDonald 2010 and MAGNIMS 2016 criteria. Different neurophysiological methods such as evoked potentials (EP), testing of
the autonomic nervous system (ANS) or polysomnography have the potential to
detect clinically silent lesions or to confirm the existence of an association
between a clinical symptom and multiple sclerosis (MS); previously undetected by
MRI. Therefore, in the most recent MRI criteria for the diagnosis of MS (MAGNIMS
consensus guidelines), neurophysiological confirmation of optic nerve
dysfunction (slowed conduction on visual EP), support dissemination in space
and, in patients without concurrent visual symptoms, dissemination in time. In
this chapter we will review the existing evidence regarding the role of
different neurophysiological tests (specifically the role of EPs, autonomic
nervous system testing and sleep testing in MS) in the diagnosis and management
of MS. PURPOSE: In patients with multiple sclerosis (MS), Double Inversion Recovery
(DIR) magnetic resoce imaging (MRI) can be used to identify cortical lesions
(CL). We sought to evaluate the reliability of CL detection on DIR
longitudinally at multiple subsequent time-points applying the MAGNIMs scoring
criteria for CLs.
METHODS: 26 MS patients received a 3T-MRI (Siemens, Skyra) with DIR at 12
time-points (TP) within a 16 months period. Scans were assessed in random order
by two different raters. Both raters separately marked all CLs on each scan and
total lesion numbers were obtained for each scan-TP and patient. After a
retrospective re-evaluation, the number of consensus CLs (conL) was defined as
the total number of CLs, which both raters finally agreed on. CLs volumes,
relative signal intensities and CLs localizations were determined. Both ratings
(conL vs. non-consensus scoring) were compared for further analysis.
RESULTS: A total number of n = 334 CLs were identified by both raters in 26 MS
patients with a first agreement of both raters on 160 out of 334 of the CLs
found (κ = 0.48). After the retrospective re-evaluation, consensus agreement
increased to 233 out of 334 CL (κ = 0.69). 93.8% of conL were visible in at
least 2 consecutive TP. 74.7% of the conL were visible in all 12 consecutive TP.
ConL had greater mean lesion volumes and higher mean signal intensities compared
to lesions that were only detected by one of the raters (p<0.05). A higher
number of CLs in the frontal, parietal, temporal and occipital lobe were
identified by both raters than the number of those only identified by one of the
raters (p<0.05).
CONCLUSIONS: After a first assessment, slightly less than a half of the CL were
considered as reliably detectable on longitudinal DIR images. A retrospective
re-evaluation notably increased the consensus agreement. However, this finding
is narrowed, considering the fact that retrospective evaluation steps might not
be practicable in clinical routine. Lesions that were not reliably identifiable
by both raters seem to be characterized by lower signal intensity and smaller
size, or located in distinct anatomical brain regions. OBJECTIVES: We compared validity of 2010 McDonald and newly proposed 2016
Magnetic Resoce Imaging in Multiple Sclerosis (MAGNIMS) criteria for
dissemination in space (DIS) in predicting the conversion to clinically definite
multiple sclerosis (CDMS) in patients with clinically isolated syndrome (CIS).
METHODS: Between 2006 and 2016, we enrolled 170 patients who had a first
clinical event suggestive of multiple sclerosis (MS) from seven referral
hospitals in Korea. Patients were classified into two groups based on the main
outcome at the last follow-up: CDMS converters, who experienced a second attack,
and non-converters.
RESULTS: Of 170 patients with mean follow-up duration of 54 months, 51%
converted to CDMS. The sensitivity, specificity, accuracy, and positive and
negative predictive values of 2010 McDonald criteria were 70.9%, 63.1%, 67.1%,
66.3%, and 67.9%, and those for 2016 MAGNIMS criteria were 88.4%, 46.4%, 67.7%,
62.8%, and 79.6%, respectively. When we excluded 80 patients who underwent
disease-modifying therapy before the second clinical event, the specificity
increased to 92.3% and 84.6%, but the sensitivity decreased to 58.8% and 82.4%
for 2010 McDonald and 2016 MAGNIMS criteria, respectively.
CONCLUSION: 2016 MAGNIMS magnetic resoce imaging (MRI) criteria for DIS
showed higher sensitivity but lower specificity than 2010 McDonald criteria in
predicting conversion to CDMS in CIS patients. BACKGROUND: In 2016, the Magnetic Resoce Imaging in Multiple Sclerosis
(MAGNIMS) network proposed modifications to the MRI criteria to define
dissemination in space (DIS) and time (DIT) for the diagnosis of multiple
sclerosis in patients with clinically isolated syndrome (CIS). Changes to the
DIS definition included removal of the distinction between symptomatic and
asymptomatic lesions, increasing the number of lesions needed to define
periventricular involvement to three, combining cortical and juxtacortical
lesions, and inclusion of optic nerve evaluation. For DIT, removal of the
distinction between symptomatic and asymptomatic lesions was suggested. We
compared the performance of the 2010 McDonald and 2016 MAGNIMS criteria for
multiple sclerosis diagnosis in a large multicentre cohort of patients with CIS
to provide evidence to guide revisions of multiple sclerosis diagnostic
criteria.
METHODS: Brain and spinal cord MRI and optic nerve assessments from patients
with typical CIS suggestive of multiple sclerosis done less than 3 months from
clinical onset in eight European multiple sclerosis centres were included in
this retrospective study. Eligible patients were 16-60 years, and had a first
CIS suggestive of CNS demyelination and typical of relapsing-remitting multiple
sclerosis, a complete neurological examination, a baseline brain and spinal cord
MRI scan obtained less than 3 months from clinical onset, and a follow-up brain
scan obtained less than 12 months from CIS onset. We recorded occurrence of a
second clinical attack (clinically definite multiple sclerosis) at months 36 and
60. We evaluated MRI criteria performance for DIS, DIT, and DIS plus DIT with a
time-dependent receiver operating characteristic curve analysis.
FINDINGS: Between June 16, 1995, and Jan 27, 2017, 571 patients with CIS were
screened, of whom 368 met all study inclusion criteria. At the last evaluation
(median 50·0 months [IQR 27·0-78·4]), 189 (51%) of 368 patients developed
clinically definite multiple sclerosis. At 36 months, the two DIS criteria
showed high sensitivity (2010 McDonald 0·91 [95% CI 0·85-0·94] and 2016 MAGNIMS
0·93 [0·88-0·96]), similar specificity (0·33 [0·25-0·42] and 0·32 [0·24-0·41]),
and similar area under the curve values (AUC; 0·62 [0·57-0·67] and 0·63
[0·58-0·67]). Performance was not affected by inclusion of symptomatic lesions
(sensitivity 0·92 [0·87-0·96], specificity 0·31 [0·23-0·40], AUC 0·62
[0·57-0·66]) or cortical lesions (sensitivity 0·92 [0·87-0·95], specificity 0·32
[0·24-0·41], AUC 0·62 [0·57-0·67]). Requirement of three periventricular lesions
resulted in slightly lower sensitivity (0·85 [0·78-0·90], slightly higher
specificity (0·40 [0·32-0·50], and similar AUC (0·63 [0·57-0·68]). Inclusion of
optic nerve evaluation resulted in similar sensitivity (0·92 [0·87-0·96]), and
slightly lower specificity (0·26 [0·18-0·34]) and AUC (0·59 [0·55-0·64]). AUC
values were also similar for DIT (2010 McDonald 0·61 [0·55-0·67] and 2016
MAGNIMS 0·61 [0·55-0·66]) and DIS plus DIT (0·62 [0·56-0·67] and 0·64
[0·58-0·69]).
INTERPRETATION: The 2016 MAGNIMS criteria showed similar accuracy to the 2010
McDonald criteria in predicting the development of clinically definite multiple
sclerosis. Inclusion of symptomatic lesions is expected to simplify the clinical
use of MRI criteria without reducing accuracy, and our findings suggest that
needing three lesions to define periventricular involvement might slightly
increase specificity, suggesting that these two factors could be considered
during further revisions of multiple sclerosis diagnostic criteria.
FUNDING: UK MS Society, National Institute for Health Research University
College London Hospitals Biomedical Research Centre, Dutch MS Research
Foundation. BACKGROUND: MRI and laboratory features have been incorporated into
international diagnostic criteria for multiple sclerosis. We assessed the
pattern of MRI lesions and contributions of cerebrospinal fluid (CSF) and serum
antibody findings that best identifies children with multiple sclerosis, and the
applicability of international diagnostic criteria in the paediatric context.
METHODS: In this prospective cohort study, detailed clinical assessments, serum
and CSF studies, and MRI scans were done in youth (aged 0·46-17·87 years) with
incidental acquired demyelinating syndrome. Participants were examined
prospectively to identify relapsing disease. All MRI scans were assessed using a
validated scoring method. A random forest classifier identified imaging and
laboratory features that best predicted a multiple sclerosis or monophasic
outcome. Performance of the 2001, 2010, and 2017 international McDonald criteria
for the diagnosis of multiple sclerosis, the 2016 MRI in multiple sclerosis
(MAGNIMS) criteria, and our 2011 proposed (Verhey) criteria were determined;
performance was adjudicated with generalised linear models.
FINDINGS: Between Sept 1, 2004, and June 30, 2017, we included 324 participants
with median follow-up of 72 months (range 6-150), 71 (22%) participants with
multiple sclerosis, 237 (73%) with monophasic acquired demyelinating syndrome,
14 (4%) with relapsing non-multiple sclerosis, and two (1%) with alternative
diagnoses. We scored 2391 brain, 444 spinal, and 67 dedicated orbital MRI scans.
One or more T1 hypointense lesions plus one or more periventricular lesions
(Verhey criteria) best predicted multiple sclerosis outcome. Performance of the
2017 McDonald criteria was comparable to the 2010 McDonald criteria and was
easier to adjudicate. The ability of CSF oligoclonal bands to substitute for the
requirement for both enhancing and non-enhancing lesions in the 2017 McDonald
criteria improved its performance compared with the 2010 criteria. Myelin
oligodendrocyte testing at baseline did not improve performance of the 2017
McDonald criteria.
INTERPRETATION: The 2017 McDonald criteria for the diagnosis of multiple
sclerosis, as applied at the time of incident attack, perform well in
identifying children and youth with multiple sclerosis, indicating that the same
diagnostic criteria for multiple sclerosis apply across the age span. The
presence of so-called black holes on MRI and periventricular lesions at baseline
(Verhey criteria) also effectively distinguish children with multiple sclerosis
from children with monophasic demyelination. The presence of CSF oligoclonal
bands improve diagnostic accuracy. Myelin oligodendrocyte glycoprotein
antibodies identify children with acute disseminated encephalomyelitis, and
those with relapsing non-multiple sclerosis, most of whom do not meet 2017
McDonald criteria at onset.
FUNDING: The Multiple Sclerosis Scientific Research Foundation and The
Children's Hospital of Philadelphia. |
Is SATB1 expressed in thymocytes? | A thymocyte factor SATB1 suppresses transcription of stably integrated matrix-attachment region-linked reporter genes. SATB1 is a homeodomain protein and is predominantly expressed in thymocytes. In this study we show that special AT-rich binding protein 1 (SATB1), a T lineage-enriched chromatin organizer and regulator, is induced in response to TCR signaling during early thymocyte development | SATB1 specifically recognizes and binds to specialized genomic regions with an
ATC sequence context with high base-unpairing propensity. Such base-unpairing
regions (BURs) are typically identified within nuclear scaffold- or
matrix-attachment regions (S/MARs). SATB1 is a homeodomain protein and is
predomitly expressed in thymocytes. We obtained BHK cell lines expressing low
levels of SATB1 by stable transfection and investigated its effect on stably
integrated MAR-linked SV40 enhancer/promoter-driven luciferase reporter genes.
For this study, both naturally occurring and synthetic MARs, as well as an
AT-rich non-MAR control, were tested. Previous studies demonstrated that MAR
sequences augment transcription of the linked reporter luciferase gene. Here, we
show that SATB1 dramatically reduces the high levels of MAR-linked luciferase
gene transcription. Transcription was virtually abolished for a reporter gene
surrounded by two MARs at the 5' and 3' ends of the gene, which otherwise confer
the highest level of transcriptional augmentation. On the other hand, SATB1 did
not affect expression of an AT-rich non-MAR-linked luciferase gene or of
endogenous housekeeping genes. This study shows that SATB1 acts as a strong
transcriptional suppressor on a reporter gene linked to MARs when it is stably
integrated into chromatin. The X-linked lymphocyte-regulated (Xlr) protein is a 30,000 Mr nuclear protein
bearing homology with meiosis-specific proteins and expressed in late stage B
lymphoid cell lines. In the present study we investigated its expression in the
T lymphoid lineage. In adults, a high level of expression was detected in
CD4-CD8- thymocytes. Most remarkably, the peak of Xlr expression occurred early
during thymus cell ontogeny, precisely on days 14-15 of gestation, and was
associated with the first wave of pre-T cell differentiation. Its onset preceded
the rearrangement of TCR genes, as Xlr expression was conserved in thymus cells
from RAG1(0/0) mice. The lower expression of Xlr on day 13 of fetal development,
the bright Thy1+ phenotype of Xlr-positive cells, their large size, and their
absence from subcapsular areas suggest that Xlr expression must be turned on
within the thymus and not in prethymic precursors. From day 16 of gestation, Xlr
expression decreased markedly. At birth and later, Xlr(high) cells were mostly
large cells scattered throughout the cortical area. As shown by confocal
microscopy, expression of Xlr closely overlapped that of SATB1, which binds
special AT-rich DNA sequences associated with the nuclear matrix and plays an
important regulatory role for many genes. The remarkably regulated expression of
Xlr in the lymphoid cell lineage and of its homologue Xmr in the germ cell
lineage suggests that they might play an important role in chromatin metabolism
at critical stages of differentiation during which the genome undergoes
irreversible rearrangements. Studies have suggested that binding of the SATB1 protein to L2a, a matrix
association region located 4.5 kb 5' to the mouse CD8alpha gene, positively
affects CD8 expression in T cells. Therefore, experiments were performed to
determine the effect on T cell development of reduced expression of SATB1.
Because homozygous SATB1-null mice do not survive to adulthood due to non-thymus
autonomous defects, mice were produced that were homozygous for a T
cell-specific SATB1-antisense transgene and heterozygous for a SATB1-null
allele. Thymic SATB1 protein was reduced significantly in these mice, and the
major cellular phenotype observed was a significant reduction in the percentage
of CD8SP T cells in thymus, spleen, and lymph nodes. Mice were smaller than wild
type but generally healthy, and besides a general reduction in cellularity and a
slight increase in surface CD3 expression on CD8SP thymocytes, the composition
of the thymus was similar to wild type. The reduction in thymic SATB1 does not
lead to the variegated expression of CD8-negative single positive thymocytes
seen upon deletion of several regulatory elements and suggested by others to
reflect failure to activate the CD8 locus. Thus, the present results point to an
essential role for SATB1 late in the development and maturation of CD8SP T
cells. T lymphocyte development and differentiation is a multi-step process that begins
in the thymus and completed in the periphery. Sequential development of
thymocytes is dependent on T cell receptor (TCR) signaling and an array of
transcription factors. In this study we show that special AT-rich binding
protein 1 (SATB1), a T lineage-enriched chromatin organizer and regulator, is
induced in response to TCR signaling during early thymocyte development. SATB1
expression profile coincides with T lineage commitment and upregulation of SATB1
correlates with positive selection of thymocytes. CD4 thymocytes exhibit a
characteristic bimodal expression pattern that corresponds to immature and
mature CD4 thymocytes. We also demonstrate that GATA3, the key transcriptional
regulator of αβ T cells positively regulates SATB1 expression in thymocytes
suggesting an important role for SATB1 during T cell development. |
Which company produces ORMD-0801? | ORMD-0801 is produced by Oramed Pharmaceuticals. | The unpredictable behavior of uncontrolled type 1 diabetes often involves
frequent swings in blood glucose levels that impact maintece of a daily
routine. An intensified insulin regimen is often unsuccessful, while other
therapeutic options, such as amylin analog injections, use of continuous glucose
sensors, and islet or pancreas transplantation are of limited clinical use. In
efforts to provide patients with a more compliable treatment method, Oramed
Pharmaceuticals tested the capacity of its oral insulin capsule (ORMD-0801, 8 mg
insulin) in addressing this resistant clinical state. Eight Type I diabetes
patients with uncontrolled diabetes (HbA1c: 7.5-10%) were monitored throughout
the 15-day study period by means of a blind continuous glucose monitoring
device. Baseline patient blood glucose behavior was monitored and recorded over
a five-day pretreatment screening period. During the ensuing ten-day treatment
phase, patients were asked to conduct themselves as usual and to self-administer
an oral insulin capsule three times daily, just prior to meal intake. CGM data
sufficient for pharmacodynamics analyses were obtained from 6 of the 8 subjects.
Treatment with ORMD-0801 was associated with a significant 24.4% reduction in
the frequencies of glucose readings >200 mg/dL (60.1 ± 7.9% pretreatment vs.
45.4 ± 4.9% during ORMD-0801 treatment; p = 0.023) and a significant mean 16.6%
decrease in glucose area under the curve (AUC) (66055 ± 5547 mg/dL/24 hours vs.
55060 ± 3068 mg/dL/24 hours, p = 0.023), with a greater decrease during the
early evening hours. In conclusion, ORMD-0801 oral insulin capsules in
conjunction with subcutaneous insulin injections, well tolerated and effectively
reduced glycemia throughout the day.
TRIAL REGISTRATION: Clinicaltrials.gov NCT00867594. |
In which cell organelle is the SAF-A protein localized? | saf-a/hnrnp u is an abundant nuclear protein that interacts specifically with nuclear matrix attachment region dna | One class of heterogeneous nuclear ribonucleoproteins (hnRNPs), AUF1/hnRNP D,
consists of four isoform proteins (p45, p42, p40, and p37) which are generated
by alternative splicing. The present study was therefore undertaken to clarify
any isoform-specific differences in terms of their functions and
nucleocytoplasmic localization. All isoforms primarily localized in the nucleus.
However, heterokaryon analysis and a study using RNA polymerase II inhibitor
revealed that p40/p37 exhibited a continuous shuttling between the nucleus and
cytoplasm. Constant nuclear retention activity was mapped to the
p45/p42-specific sequence at the C-terminal region, which is retained by
alternative splicing. Using this domain as a probe, we performed a yeast
two-hybrid screening and we found that scaffold attachment factor B (SAF-B), a
nuclear matrix-associated protein, exhibits protein-protein interaction to this
region. Colocalization of p45/p42 and SAF-B was observed as a speckle in the
nucleus. Interestingly, p45/p42 isoforms appeared to act as a negative regulator
in gene expression by forming a complex with SAF-B. Thus, the present study
revealed that the isoform-specific functions of AUF1/hnRNP D are defined by
intracellular shuttling capacity. SAF-A/hnRNP U is an abundant nuclear protein that interacts specifically with
nuclear matrix attachment region DNA (MAR) and RNA as a component of hnRNPs.
SAF-A/hnRNP U was also shown to specifically bind mouse major satellite DNA
(satMa). Antibodies against SAF-A and GFP-fusion constructs were used in the
current work in order to trace SAF-A localization. In accordance with its
diverse nucleic acid binding specificity, SAF-A was found to be localized in
three different domains: outside the chromosomes, on the surface of the
chromosome arms (probably MARs), and in the centromere region where it
apparently binds specifically to the satMa. GFP-fusion constructs with different
SAF-A/hnRNP U domains confirms the functional significance of the protein's
functional domains in interphase cells. In telophase cells, the anti-SAF-A
antibody signal appeared as a kind of network covering unfolded chromosomes. BACKGROUND: Scaffold attachment factor A (SAF-A) participates in the regulation
of gene expression by organizing chromatin into transcriptionally active domains
and by interacting directly with RNA polymerase II.
METHODOLOGY: Here we use co-localization, co-immunoprecipitation (co-IP) and in
situ proximity ligation assay (PLA) to identify Brahma Related Gene 1 (BRG1),
the ATP-driven motor of the human SWI-SNF chromatin remodeling complex, as
another SAF-A interaction partner in mouse embryonic stem (mES) cells. We also
employ RNA interference to investigate functional aspects of the SAF-A/BRG1
interaction.
PRINCIPAL FINDINGS: We find that endogenous SAF-A protein interacts with
endogenous BRG1 protein in mES cells, and that the interaction does not solely
depend on the presence of mRNA. Moreover the interaction remains intact when
cells are induced to differentiate. Functional analyses reveal that dual
depletion of SAF-A and BRG1 abolishes global transcription by RNA polymerase II,
while the nucleolar RNA polymerase I transcription machinery remains unaffected.
CONCLUSIONS: We demonstrate that SAF-A interacts with BRG1 and that both
components are required for RNA Polymerase II Mediated Transcription. |
Describe Twiddler Syndrome. | Twiddler syndrome is described as a spontaneous rotation or intentional external manipulation of implanted cardiac or occasionally deep brain stimulation (DBS) devices. | We report upon a case of total retraction of an electrode (Twiddler syndrom) in
an infected pacemaker battery. The silk-thread fixation was still fastened at
the right place on the electrode; the tissue owing to the inflammation was no
longer sufficient as a fixation point. The casues of this total retraction of
the electrode are the following factors: the battery hat sufficient freedom of
movement for rotation following exudation into the pacemaker cavity, the
electrode was elastic and above all the pacemaker system was infected which
could no longer guarantee a sufficient fixation of the electrode in the infected
tissue. Attention is drawn to the necessity to remove an infected pacemaker
system. Twiddler's syndrome describes the intentional external manipulation or
spontaneous rotation of implanted devices such as cardiac pacemakers. Here we
report the same phenomenon occurring in a patient with an implanted deep brain
stimulator generator. The clinical syndrome is described and potential technical
nuances to prevent its occurrence are suggested. Twiddler syndrome occurs when a patient intentionally or unintentionally
manipulates an implantable generator (usually a pacemaker) and dislodges the
pacing leads, causing malfunction of the device. Though the syndrome has been
described in patients with pacemakers, to our knowledge only one spontaneous
case has been described in patients undergoing deep brain stimulation for
movement disorders. We report the clinical cases of two patients with
Parkinson's disease who had subthalamic bilateral electrodes implanted and
presented the twiddler syndrome 2 and 3 years after surgery. We analysed the
possible mechanisms of this syndrome and note that twiddler syndrome should be
suspected in patients undergoing deep brain stimulation and showing hardware
dysfunction. Andersen-Tawil syndrome is an autosomal domit condition characterized by
dysmorphic features, periodic paralysis, and ventricular arrhythmias. Twiddler
syndrome is characterized by intentional or inadvertent manipulation of
implanted devices in the pacemaker pocket. We describe an unusual case of an
8-year-old girl who had both syndromes. Twiddler syndrome is a form of pacemaker lead dislocation caused by the coiling
of the pacemaker leads due to pulse generator rotation on its long axis. Similar
to Twiddler syndrome, Reel syndrome occurs due to rotation of the pulse
generator on its transverse axis, leading to lead dislocation or fracture,
followed by clinical symptoms of dislodged leads. We report a case of 75 years
old woman with Reel syndrome presenting with syncope. Twiddler syndrome is described as a spontaneous rotation or intentional external
manipulation of implanted cardiac or occasionally deep brain stimulation (DBS)
devices. We report this hardware related complication in a patient with tremor
domit Parkinson's disease (PD), who underwent unilateral subthalamic nucleus
(STN) DBS and subsequently developed twiddler syndrome. The clinical course of
twiddler syndrome in this patient is described. Some surgical nuances which may
prevent its occurrence are suggested. Our case report indicates that twiddler
syndrome occurs in DBS patients. Impedance check of DBS hardware, plain chest
X-ray, or palpation for a knobbly extension lead through the skin above the IPG
allows the correct diagnosis and subsequently a prompt surgical revision. Our
subsequent literature review revealed only 10 patients with twiddler syndrome in
DBS patient population worldwide. This number may suggest that this syndrome may
be unrecognized or underreported, given the number of patients with movement
disorders implanted with DBS hardware worldwide. A 65-year-old male patient with a history of ischemic cardiomyopathy developed
ventricular tachycardia resulting in presyncope. An ICD was indicated for
secondary prophylaxis of ventricular tachyarrhythmias. A dual chamber ICD was
implanted from the right side because insertion of the device from the left side
was unfeasible after surgery of a left subscapularis tendon lesion. ICD
implantation and testing of defibrillation threshold were uneventful. During
early follow-up a progressive increase of the stimulation threshold was
detected. On chest X-ray coiling of both atrial and ventricular leads was noted
and caused inadvertently by active shoulder-arm physiotherapy. Complete revision
of the ICD system was necessary for restoration of the pacemaker function of the
ICD. This unique case highlights important steps for early recognition and
prevention of Twiddler's syndrome that may occur due to physiotherapy treatment
even without abnormal manipulations by the patient. OBJECTIVES: This cumulative case study was performed to properly address the
possible mechanisms, forms, and consequences of "twiddler's," "reel," and
"ratchet" syndromes.
BACKGROUND: Twiddler's, reel, and ratchet syndromes are rare entities
responsible for lead displacement of cardiac implantable electronic devices
(CIED).
METHODS: From 2007 to 2012, 1,472 CIED were implanted at our center. Eighty-nine
cases were reviewed for failure of pacing circuit integrity. Only 9 met the
inclusion criteria for idiopathic lead migration (ILM) and were grouped as ILM
(twiddler) or ILM (reel). For a pooled analysis of cases, a review of the
literature from 1990 to 2012 was performed, and the authors identified 78 cases
from 64 publications.
RESULTS: The study population consisted of 87 cases (45 women; median age, 66
years; 46 with ILM [twiddler] and 41 with ILM [reel]). Migration affected only 1
lead in 65% of 46 devices with more than 1 lead. None of the previously reported
risk factors-manual manipulation of the device, elderly age, obesity, oversized
pocket, and psychiatric history-correlated with the risk of ILM.
CONCLUSIONS: Neither manual manipulation of the device nor the other traditional
risk factors reported in the literature for ILM syndrome correlated with the
risk of ILM. Publisher: Le syndrome de Twiddler est une cause exceptionnelle de dysfonction
de prothèses cardiaques résultant d’un déplacement de sonde secondaire à la
manipulation délibérée ou inconsciente du boîtier. Nous rapportons le cas d’un
patient admis pour arrêt cardiorespiratoire sur bradycardie extrême et
initialement implanté 6 semaines plus tôt pour une fibrillation ventriculaire
idiopathique sans cause ischémique documentée ni troubles de conductions
majeurs. Le patient a ainsi bénéficié d’une extraction avec réimplantation d’une
nouvelle sonde de défibrillation. L’originalité de cette observation est
soulignée par la survenue d’un bloc auriculoventriculaire syncopal inaugural
jusque-là méconnu révélant un syndrome de Twiddler chez un patient initialement
implanté d’un défibrillateur en prévention secondaire pour une fibrillation
ventriculaire idiopathique. Twiddler syndrome is an uncommon complication that occurs by twisting of the
generator and may cause torsion, dislodgement, and injury of the leads. We
report a rare case of a twiddler syndrome associated with an abdominal permanent
pacemaker. Abdominal twiddler syndrome may possess a unique mechanism, which may
not be seen in chest twiddler syndrome. |
What are Drosophila's balancer chromosomes? | genetic reagents | Multiple sub-vital effects, here designated as reductions in fitness S1-S5, for
the second chromosome gene 'daughterless' (da) of Drosophila melanogaster were
described as (S1) a recessive maternal lethality for daughters, (S2) a reduced
fertility of da/da females, (S3) a recessive sub-vital zygotic effect, (S4) a
recessive female-specific zygotic effect and (S5) a recessive maternal
interaction effect on sons. (For S1-3 see also: Bell, 1954; Sandler, 1972;
Cline, 1976). These five distinct effects were initially quantified from
estimates of viability in single generation crossing experiments. Dynamic
estimates of these fitness parameters were obtained by fitting the elimination
rate of da from a series of large random mating cage populations to a recurrence
equation by the method of minimum chi-square. The stability of these estimates
discerns those effects which are truly pleiotropic versus those due to linked
genes. The dynamic estimates supported only S1 and S4 effects. Evidence for S2
and S5 was indeterminate, but the S3 effect was rejected (P less than 0.01). The
observed reduction in fitness, supposedly due to this recessive zygotic effect
for da, was most likely the result of linked deleterious genes. These results
indicate that pleiotropic vital effects observed in single generation test-cross
matings may be caused by linked genes rather than the specific mutant per se.
This problem is of particular importance when the mutant allele has been
maintained with a balancer chromosome. Experiments on the rescue of daughters
from da/da mothers with low temperatures during embryogenesis and with
dechorionation of eggs were described in which the findings failed to confirm
previously reported actions of the da gene. Modifying genes rather than
environmental variables were cited as the probable cause for these conflicting
results. Balancer chromosomes are genetic reagents that are used in Drosophila
melanogaster for stock maintece and mutagenesis screens. Despite their
utility, balancer chromosomes are rarely used in mice because they are difficult
to generate using conventional methods. Here we describe the engineering of a
mouse balancer chromosome with the Cre-loxP recombination system. The chromosome
features a 24-centiMorgan (cM) inversion between Trp53 (also known as p53) and
Wnt3 on mouse chromosome 11 that is recessive lethal and domitly marked with
a K14-Agouti transgene. When allelic to a wild-type chromosome, the inversion
suppresses crossing over in the inversion interval, accompanied by elevated
recombination in the flanking regions. The inversion functions as a balancer
chromosome because it can be used to maintain a lethal mutation in the inversion
interval as a self-sustaining trans-heterozygous stock. This strategy can be
used to generate similar genetic reagents throughout the mouse genome.
Engineering of visibly marked inversions and deficiencies is an important step
toward functional analyses of the mouse genome and will facilitate large-scale
mutagenesis programs. Multiply inverted balancer chromosomes that suppress exchange with their
homologs are an essential part of the Drosophila melanogaster genetic toolkit.
Despite their widespread use, the organization of balancer chromosomes has not
been characterized at the molecular level, and the degree of sequence variation
among copies of balancer chromosomes is unknown. To map inversion breakpoints
and study potential diversity in descendants of a structurally identical
balancer chromosome, we sequenced a panel of laboratory stocks containing the
most widely used X chromosome balancer, First Multiple 7 (FM7). We mapped the
locations of FM7 breakpoints to precise euchromatic coordinates and identified
the flanking sequence of breakpoints in heterochromatic regions. Analysis of SNP
variation revealed megabase-scale blocks of sequence divergence among currently
used FM7 stocks. We present evidence that this divergence arose through rare
double-crossover events that replaced a female-sterile allele of the singed gene
(sn(X2)) on FM7c with a sequence from balanced chromosomes. We propose that
although double-crossover events are rare in individual crosses, many FM7c
chromosomes in the Bloomington Drosophila Stock Center have lost sn(X2) by this
mechanism on a historical timescale. Finally, we characterize the original
allele of the Bar gene (B(1)) that is carried on FM7, and validate the
hypothesis that the origin and subsequent reversion of the B(1) duplication are
mediated by unequal exchange. Our results reject a simple nonrecombining, clonal
mode for the laboratory evolution of balancer chromosomes and have implications
for how balancer chromosomes should be used in the design and interpretation of
genetic experiments in Drosophila. A model for the evolution of senescence known as "antagonistic pleiotropy" makes
the specific prediction that there should be a negative genetic correlation
between early- and late-age traits associated with fitness. This model has
previously been tested by classical quantitative-genetic means including
sib-analysis and artificial selection. We used the approach of chromosome
extraction, which has both advantages and disadvantages compared to classical
techniques, to test the model further. From four isogenic lines of Drosophila
melanogaster, four sets of recombit extracted lines were constructed using
standard balancer-chromosome techniques. The four parental lines and 53
recombits were reared under controlled laboratory conditions and isolated as
pairs for scoring daily fecundity and longevity. Even though the design is not
optimal for estimating classical components of genetic variance, it afforded a
uniquely direct test of the magnitude of environmental covariances, while giving
a detailed genetic picture of part of the genome. There were clear differences
among the recombit series in the distribution of mean longevity and early
fecundity. The genetic correlation between early fecundity (sum of egg
production for the first five days posteclosion) and female longevity was
significantly negative in only one of the recombit series. When all lines
were considered together, the phenotypic correlation between these traits was
significantly negative (P < 0.02), while the broad-sense genetic correlation was
-0.219 (P < 0.11). This result may be viewed as weakly consistent with the model
of antagonistic pleiotropy, but other aspects of the data are at odds with the
model. |
What is iodine thyroid blocking? | High doses of potassium iodide are effective to block radioiodine thyroid uptake and to prevent development of thyroid cancer years later. | (131)I, when released in a radiological or nuclear accident as happened recently
in Fukushima, Japan, may cause thyroid cancer as a long-term consequence. Iodine
thyroid blocking (ITB) is known to reduce the risk of developing thyroid cancer.
Potential adverse effects of ITB have not been systematically investigated so
far. This article summarises the results of a review on adverse effects of ITB
based on a systematic literature search in scientific medical databases. A
meta-analysis was not performed as identified studies displayed major
heterogeneity. The search resulted in 14 articles relevant to the topic,
reporting mostly on surveys, ecological and intervention studies. Only one study
from Poland focused on effects (both desired and adverse) of an ITB intervention
following the Chernobyl accident. All other studies reported on iodine
administration in a different context. Overall, the studies did not reveal
severe adverse reactions to potassium iodide in the general public. Since ITB is
a protective measure only applied in very specific circumstances, scientifically
sound studies of adverse effects are scarce and consequently the evidence base
is weak. The assessment of adverse effects of ITB relies on indirect evidence
from related areas. This study may contribute to ongoing developments in
pharmacoepidemiology aiming to better quantify adverse effects of medications
and health care interventions including ITB. Thyroid cancer in children and adolescents has to be considered as the most
severe health consequence of a nuclear reactor emergency with release of
radioiodine into the atmosphere. High doses of potassium iodide are effective to
block radioiodine thyroid uptake and to prevent development of thyroid cancer
years later. However, there are controversies concerning thyroid cancer risk
induced by radioiodine exposure in adults. Further, the interaction of
nutritional supply of potassium iodide and radioiodine uptake as well as the
interaction of radioiodine with certain drugs has not been addressed properly in
existing guidelines and recommendations. How to proceed in case of repeated
release of radioiodine is an open, very important question which came up again
recently during the Fukushima accident. Lastly, the side effects of iodine
thyroid blocking and alternatives of this procedure have not been addressed
systematically up to now in guidelines and recommendations. These questions can
be answered as follows: in adults, the risk to develop thyroid cancer is
negligible. In countries, where nutritional iodine deficiency is still an issue,
the risk to develop thyroid cancer after a nuclear reactor emergency has to be
considered higher because the thyroid takes up more radioiodine as in the
replete condition. Similarly, in patients suffering from thyrotoxicosis,
hypothyroidism or endemic goitre not being adequately treated radioiodine uptake
is higher than in healthy people. In case of repeated or continued radioiodine
release, more than one dose of potassium iodide may be necessary and be taken up
to 1 week. Repeated iodine thyroid blocking obviously is not harmful. Side
effects of iodine thyroid blocking should not be overestimated; there is little
evidence for adverse effects in adults. Newborns and babies, however, may be
more sensitive to side effects. In the rare case of iodine hypersensitivity,
potassium perchlorate may be applied as an alternative to iodine for thyroid
blocking. The ambiguous terminology 'Iodine Prophylaxis' used for decades to provide
iodine to the population for very different purposes as well as its replacement
with 'Iodine Thyroid Blocking' is discussed and argued. Recommendations of
international organisations regarding the action level for Iodine Thyroid
Blocking and their implementation in national regulations in a few Member States
of the European Union, and particularly in Hungary, is presented and discussed. Author information:
(1)University Hospital Wuerzburg, Oberduerrbacher Str. 6, 97080 Wuerzburg,
Germany [email protected].
(2)University Hospital Wuerzburg, Oberduerrbacher Str. 6, 97080 Wuerzburg,
Germany.
(3)National Institutes for Quantum and Radiological Science and Technology
(QST), 4-9-1 Anagawa, Inage-ku, 263-8555 Chiba, Japan.
(4)Department of Internal Medicine, American University of Beirut, Riad-El-Solh
1107 2020, P.O. Box: 11-0236, Beirut, Lebanon.
(5)Institut de Radioprotection et de Sûreté Nucléaire, B.P. 17, 92262
Fontenay-aux- Roses, France.
(6)Radiation Protection Bureau, Health Canada, 775 Brookfield Rd, Ottawa, Canada
K1A 1C1.
(7)Division Radioprotection de l'Office Federal de la Santé Publique,
Schwarzenburgstrasse 157, CH-3003 Berne, Switzerland.
(8)Federal Agency for Nuclear Control, Ravensteinstraat 36, B-1000 Brussels,
Belgium.
(9)Department of Radiation Medical Sciences, Atomic Bomb Disease Institute,
Nagasaki University, 1-12-4 Sakamoto, Nagasaki 8528523, Japan.
(10)Leibniz-Institute for Prevention Research and Epidemiology (BIPS),
Achterstraße 30, 28359 Bremen, Germany.
(11)Endocrine Unit, Department of Clinical and Experimental Medicine, University
Hospital, Via Paradisa, 2, 56124 Pisa, Italy.
(12)Department of Public Health, Environmental and Social Determits of
Health, World Health Organization, 20 avenue Appia, 1211 Geneva-27, Switzerland. |
Does gavestinel improve outcomes of stroke patients? | No. In a randomized clinical trial, treatment with gavestinel within 6 hours of acute ischaemic stroke did not improve outcome. | CONTEXT: Elucidation of the ischemic cascade has helped stimulate development of
neuroprotective drugs aimed at limiting brain injury in the hours following an
ischemic stroke. To date, none of these drugs has shown clinical efficacy.
OBJECTIVE: To examine the efficacy of gavestinel (GV150526), an antagonist of
the glycine site of the N-methyl-D-aspartate receptor, as a neuroprotective
therapy for acute ischemic stroke when administered within 6 hours of symptom
onset.
DESIGN: The Glycine Antagonist in Neuroprotection (GAIN) Americas trial, a
randomized, double-blind placebo-controlled trial with enrollment from April
1998 to October 1999.
SETTING: One hundred thirty-two hospital centers across the United States and
Canada.
PATIENTS: The primary efficacy population consisted of 1367 ischemic stroke
patients with a predefined level of limb weakness and functional independence
prior to stroke, stratified at randomization by age (</=75 vs >75 years) and
initial stroke severity (National Institutes of Health [NIH] Stroke Scale scores
of 2-5, 6-13, or >/=14).
INTERVENTION: Patients were randomly assigned to receive an intravenous loading
dose (800 mg) plus 5 maintece doses (200 mg every 12 hours) of gavestinel (n
= 701) or placebo (n = 666) for 3 days.
MAIN OUTCOME MEASURE: Functional capability at 3 months, measured by the Barthel
Index (BI), with scores trichotomized as dead/0-55, 60-90, and 95-100, compared
between the gavestinel and placebo groups.
RESULTS: Treatment groups were well matched for baseline characteristics. For
each group, median NIH Stroke Scale was 12, median age was 72 years, and median
time to treatment was 5.2 hours. No statistically significant improvement on the
3-month BI trichotomy was demonstrated for gavestinel (P =.79). The proportion
who were functionally independent (BI score = 95-100) was 39% in the gavestinel
group and 37% in the placebo group. No statistically significant difference in
3-month survival was observed using Kaplan-Meier curves (P =.11). No other
secondary end point suggested an advantage for gavestinel. Among the 333
patients (24%) who received recombit tissue-type plasminogen activator, there
was also no benefit for gavestinel (P =.53). There were no serious safety
issues.
CONCLUSION: In this study, gavestinel administered up to 6 hours after an acute
ischemic stroke did not improve functional outcome at 3 months. There was only problem, it didn't work. The wonder drug, gavestinel, failed to
produce any significant treatment benefits for patients treated within six hours
after experiencing an acute ischemic stroke, according to the recent results of
a major clinical trial of the neuroprotectant. The outcome has dimmed the
optimism of hospitalists that rapid treatment would dramatically improve patient
outcomes. It has long been accepted that high concentrations of glutamate can destroy
neurons, and this is the basis of the theory of excitotoxicity during brain
injury such as stroke. Glutamate N-methyl-D-aspartate (NMDA) receptor
antagonists such as Selfotel, Aptiganel, Gavestinel and others failed to show
neuroprotective efficacy in human clinical trials or produced intolerable
central nervous system adverse effects. The failure of these agents has been
attributed to poor studies in animal models and to poorly designed clinical
trials. We also speculate that NMDA receptor antagonism may have hindered
endogenous mechanisms for neuronal survival and neuroregeneration. It remains to
be proven in human stroke whether NMDA receptor antagonism can be
neuroprotective. BACKGROUND AND PURPOSE: Improvement in the National Institutes of Health Stroke
Scale (NIHSS) 24 hours after stroke has been associated with subsequent
neurological deterioration. We hypothesized that a similar association would be
apparent for events occurring after 7 days, when acute changes from edema and
herniation are less common. We evaluated the degree of NIHSS improvement at 7
days (recovery) as a predictor of subsequent neurological deterioration from day
7 to day 90.
METHODS: We studied all patients of the Glycine Antagonist (gavestinel) In
Neuroprotection (GAIN) International Trial with ischemic stroke alive at day 7,
excluding patients with hemorrhagic events and deaths from nonstroke-related
causes. The GAIN International Trial was a randomized, double-blind,
placebo-controlled, and parallel-group trial; because the study drug had no
effect on stroke outcome, treatment groups were combined for this analysis.
Neurological deterioration was assessed by the combined measure, including: (1)
stroke-related events recorded as "serious adverse events," (2) recurrent stroke
recorded on a separate case report form, and (3) any NIHSS worsening.
RESULTS: Among 1187 patients included, 25% had >65% recovery. Deterioration was
more prevalent in the group with >65% early recovery (15.5% versus 10.3%;
P=0.01). Logistic regression modeling indicated that recovery was associated
with subsequent neurological deterioration (odds ratio, 1.2; 95% CI, 1.1 to 1.3,
per 10% recovery) after adjusting for age, NIHSS at 7 days, and stroke subtype.
CONCLUSIONS: Substantial neurological recovery at 7 days is associated with
subsequent neurological deterioration. BACKGROUND AND PURPOSE: Gavestinel, GV150526, is a selective antagonist at the
glycine site of the N-methyl-D-aspartate receptor. The safety and efficacy of
GV150526 were studied in two phase III randomized placebo-controlled clinical
trials of acute ischemic stroke patients within 6 h from onset [The Glycine
Antagonist in Neuroprotection (GAIN) International and GAIN Americas Trials]. A
planned MRI substudy within these trials investigated the effect of gavestinel
on infarct volume.
METHODS: Patients enrolled in the GAIN trials at designated MRI substudy sites
were eligible if they had a pretreatment acute cortical lesion on
diffusion-weighted MRI of at least 1.5 cm diameter or 5 cm(3). Final lesion
assessment was performed on T(2)-weighted MRI at month 3. Blinded image analysis
was performed centrally. The primary hypothesis was that gavestinel would
attenuate lesion growth from baseline relative to placebo.
RESULTS: A total of 106 patients were eligible, 75 (34 gavestinel, 41 placebo)
of whom had month 3 scans (primary analysis population). No effects of
gavestinel on infarct volume were observed in the primary or other analyses.
However, significant associations of lesion volume to clinical severity and
outcomes were observed. Ischemic lesion volume decrease was predictive of
substantial clinical improvement.
CONCLUSION: Consistent with the clinical outcomes in the GAIN trials, no effects
of gavestinel on ischemic infarction was observed. Concordance of results of the
clinical outcome trials with those of this infarct volume substudy as well the
associations of infarct volume to clinical outcomes further support the
potential role of infarct volume as a marker of outcome in dose finding and
proof of principle acute stroke trials. |
Can Systemic Lupus Erythematosus cause seizures? | In the extant literature, an increased risk of seizures has been described in several inflammatory/autoimmune disorders, including systemic lupus erythematosus (SLE) | OBJECTIVE: To evaluate the frequency and risk factors of epileptic seizures in a
large cohort of patients with systemic lupus erythematosus (SLE).
METHODS: Five hundred nineteen consecutive patients with SLE were studied, with
follow-up ranging from 4 to 7.8 years. The type and frequency of risk factors
associated with acute and recurrent epileptic seizures in SLE were determined.
RESULTS: Sixty (11.6%) patients with epileptic seizures were identified.
Epileptic seizures occurred at the onset of SLE symptoms in 19 (31.6%) and after
the onset of SLE in 41 of 60 (68.3%) patients. Fifty-three of 60 (88.3%)
patients had acute symptomatic epileptic seizures, and 7 of 60 (11.7%) had
recurrent epileptic seizures. Variables associated with acute epileptic seizures
at SLE onset were stroke (p = 0.0004) and antiphospholipid antibodies (p =
0.0013). Epileptic seizures during follow-up were related to nephritis (p =
0.001), antiphospholipid antibodies (p = 0.005), and epileptic seizures at
disease onset (p = 0.00001). All seven patients who presented recurrent
epileptic seizures had antiphospholipid syndrome and interictal epileptic
abnormalities on EEG.
CONCLUSIONS: Epileptic seizures were observed in 11.2% of systemic lupus
erythematosus (SLE) patients. Antiphospholipid antibodies and stroke were
related to epileptic seizures at SLE disease onset. Patients with renal flares,
epileptic seizures at SLE disease onset, and antiphospholipid antibodies were at
greater risk for acute symptomatic seizures during follow-up. Recurrence of
epileptic seizures occurred in 1.3% of patients and was associated with
antiphospholipid syndrome. OBJECTIVE: To examine the predictors of time-to-seizure occurrence and their
impact on damage accrual and mortality in LUMINA, a multiethnic (Hispanic,
African American and Caucasian) cohort of patients with systemic lupus
erythematosus.
METHODS: Seizures were defined as per the American College of Rheumatology (ARC)
nomenclature and case definitions for neuropsychiatric lupus syndromes. Factors
associated with time-to-seizure occurrence occurring at or after diagnosis (TD)
of systemic lupus erythematosus were examined by univariable and multivariable
Cox proportional hazard regression analyses. The impact of seizures on damage
accrual and mortality was also examined by multivariable analyses after
adjusting for variables known to affect these outcomes.
RESULTS: A total of 600 patients were included in these analyses. Of them, 40
(6.7%) developed seizures at or after TD; by multivariable analyses, disease
activity and younger age were independent predictors of a shorter
time-to-seizure occurrence (HR = 1.10 and 1.04; 95% CI 1.04 to 1.15 and 1.00 to
1.08, p = 0.0004 and 0.0304, respectively) whereas mucocutaneous involvement (HR
= 0.34, 95% CI 0.16 to 0.41, p = 0.0039) and hydroxychloroquine use (HR = 0.35,
95% CI 0.15 to 0.80, p = 0.0131) were independent predictors of a longer
time-to-seizure occurrence. Seizures were an independent contributor to damage
accrual but not to mortality.
CONCLUSIONS: Seizures tend to occur early in the course of systemic lupus
erythematosus, and contribute to damage accrual. Younger age and disease
activity are independent predictors of a shorter time-to-seizure occurrence;
antimalarials appear to have a protective role in seizure occurrence. INTRODUCTION: Juvenile systemic lupus erythematosus is more incident in female
affecting different systems including the central nervous system. The aim of
this study was to check the incidence of seizures and electroencephalographic
features in these patients.
METHOD: It was analyzed all patients with juvenile systemic lupus erythematosus
referred to the Pequeno Príncipe Hospital in Curitiba, PR, Brazil, in the year
of 2007. The patients were submitted to EEG and subdivided into two groups
according to the presence or absence of epileptic seizures. Mann-Whitney
statistical test was used.
RESULTS: Forty-nine cases were included, there were 73.45% female, with an age
between 3 and 28 years (micro=17.00 years; s=5.01 years). Seizures (13/26.50%)
were the most frequent manifestation followed by headache (13/26.50%) and
ischemic stroke (6/12.25%). Cerebral vasculites were the most frequent
alteration in neuroimage. The abnormalities of EEG were characterized by
asymmetry of the electric cerebral activity, diffuse disorganized background
activity, focal epileptiform discharges in the right central-temporal region,
generalized paroxysmal of 3 Hz spike-waves, and bursts of theta-delta slowness
activity in the right parietal-occiptal region. The statistic analysis showed no
significantly difference between age of onset of symptoms and the risk of
seizures (p 0.675) as well as between time of the disease and the risk of
seizures (p 0.436).
CONCLUSION: Neurologic manifestations, in special epileptic seizures, are
frequent in systemic lupus erythematosus. Age of onset of symptoms and the time
of disease did not increase the risk of epileptic seizures in this disease. OBJECTIVE: The aim of this study was to describe the frequency, attribution,
outcome and predictors of seizures in systemic lupus erythematosus (SLE).
METHODS: The Systemic Lupus International Collaborating Clinics, or SLICC,
performed a prospective inception cohort study. Demographic variables, global
SLE disease activity (SLE Disease Activity Index 2000), cumulative organ damage
(SLICC/American College of Rheumatology Damage Index (SDI)) and neuropsychiatric
events were recorded at enrolment and annually. Lupus anticoagulant,
anticardiolipin, anti-β(2) glycoprotein-I, antiribosomal P and anti-NR2
glutamate receptor antibodies were measured at enrolment. Physician outcomes of
seizures were recorded. Patient outcomes were derived from the SF-36 (36-Item
Short Form Health Survey) mental component summary and physical component
summary scores. Statistical analyses included Cox and linear regressions.
RESULTS: The cohort was 89.4% female with a mean follow-up of 3.5±2.9 years. Of
1631 patients, 75 (4.6%) had ≥1 seizure, the majority around the time of SLE
diagnosis. Multivariate analysis indicated a higher risk of seizures with
African race/ethnicity (HR (CI): 1.97 (1.07 to 3.63); p=0.03) and lower
education status (1.97 (1.21 to 3.19); p<0.01). Higher damage scores (without
neuropsychiatric variables) were associated with an increased risk of subsequent
seizures (SDI=1:3.93 (1.46 to 10.55); SDI=2 or 3:1.57 (0.32 to 7.65); SDI≥4:7.86
(0.89 to 69.06); p=0.03). There was an association with disease activity but not
with autoantibodies. Seizures attributed to SLE frequently resolved (59/78
(76%)) in the absence of antiseizure drugs. There was no significant impact on
the mental component summary or physical component summary scores. Antimalarial
drugs in the absence of immunosuppressive agents were associated with reduced
seizure risk (0.07 (0.01 to 0.66); p=0.03).
CONCLUSION: Seizures occurred close to SLE diagnosis, in patients with African
race/ethnicity, lower educational status and cumulative organ damage. Most
seizures resolved without a negative impact on health-related quality of life.
Antimalarial drugs were associated with a protective effect. Seizures are one of the most serious neuropsychiatric manifestations of systemic
lupus erythematous (SLE). This descriptive and retrospective study aims at
describing clinical and paraclinical features and therapeutic approach of
seizures in patients with SLE. The characteristics of the seizure group was
compared to those of a control group (patients with LES who had not presented
seizures). A total of 177 patients were included in these analyses. Among them,
14 (8 %) developed seizures before, at or after the SLE diagnosis. The age of
occurrence of seizures was younger than for other complications of the disease.
There was no significant association with the antiphospholipid syndrome. Disease
activity in these patients was significantly higher than in the control group.
During the follow up, the subjects being under anticonvulsants and/or
corticosteroids and/or immunosuppressive therapy, we observed good outcomes
(n=5), re-occurence of seizures (n=4), cognitive impairment (n=3 ) and death
(n=2). Our study shows that seizures tend to occur early in the course of SLE,
in the context of important disease activity and other serious clinical
manifestations and in younger individuals. Seizures portend a negative impact on
the overall long-term prognosis and quality of life in patients with SLE. Posterior reversible encephalopathy syndrome (PRES) in patients with systemic
lupus erythematosus (SLE) has been recognized increasingly. This study aimed to
determine the prevalence, clinical features, brain imaging findings, outcomes,
and associated factors of PRES in Thai SLE patients. SLE patients with PRES were
identified from the lupus cohort of Chiang Mai University. Controls were SLE
patients with a hospital number close to and actually had SLE diagnosis within 5
years of the case (case:control ratio = 1:4). Of 1,332 SLE patients, 30 episodes
of PRES were identified in 24 female SLE patients (prevalence 1.80%). The mean ±
SD age at SLE diagnosis and at onset of PRES was 25.02 ± 13.78 and 28.31 ±
12.61 years, respectively. Seizure was the most common presenting symptom, as
seen in 28 episodes, followed by acute severe headache in 17, alteration of
consciousness in 17, nausea and vomiting in 10, blurred vision in 11, and
hemiparesis in 3. Abrupt increase in blood pressure and active nephritis were
seen in 29 and 26 of the episodes, respectively. Urine protein/creatinine ratio
> 1.00 (OR 15.72, 95% CI 3.12-79.12, p = 0.001) and hemoglobin < 10 gm/dL (OR
5.12, 95% CI 1.37-19.15, p = 0.015) were associated factors for developing PRES.
During the observation period, 7 patients in the PRES group and 8 in the control
group died (p = 0.015). PRES was uncommon in SLE patients, but associated with a
high mortality rate. Active nephritis and anemia were associated factors of PRES
in Thai SLE patients. |
What disease is associated with a Malar rash? | Cutaneous manifestations of SLE are frequently the presenting symptoms, typically noted in the classic malar "butterfly" rash; | BACKGROUND: Systemic lupus erythematosus (SLE) may involve any number of organ
systems and varies greatly in the severity and type of involvement. Cutaneous
manifestations of SLE are equally numerous and varied throughout the course of
the disease within an individual, as well as varying between patients. Cutaneous
manifestations of SLE are frequently the presenting symptoms, typically noted in
the classic malar "butterfly" rash; however, other cutaneous patterns are
frequently observed.
METHODS: We present here two patients who presented with what was thought to be
acne refractory to treatment.
RESULTS: These patients actually were found to have a facial eruption associated
with SLE as confirmed by skin biopsy.
CONCLUSIONS: The importance of investigating atypical or treatment-resistant
eruptions, especially in patients experiencing other symptoms, is emphasized. BACKGROUND: Malar rash is one of the three cutaneous diagnostic criteria of
systemic lupus erythematosus (SLE). Although its clinical recognition is often
straightforward, the differential diagnosis with erythematotelangiectatic
rosacea may sometimes be challenging.
OBJECTIVE: To describe dermoscopic features of SLE malar rash and investigate
the accuracy of dermoscopy for the differential diagnosis with
erythematotelangiectatic rosacea.
METHODS: A representative dermoscopic image of target areas was evaluated for
the presence of specific features. Fisher's test was used to compare their
prevalence between the two cohorts, and accuracy parameters (specificity,
sensitivity, and positive and negative predictive values) were evaluated.
RESULTS: Twenty-eight patients were included in the analysis, of which 13 had
SLE malar rash and 15 erythematotelangiectatic rosacea. The main dermoscopic
features of malar rash were reddish/salmon-coloured follicular dots surrounded
by white halos ('inverse strawberry' pattern), being present in 53.9% of the
cases, while network-like vessels (vascular polygons) turned out to be the main
feature of erythematotelangiectatic rosacea, with a prevalence of 93.3%. The
comparative analysis showed that the 'inverse strawberry' pattern was
significantly more common in SLE malar rash, with a specificity of 86.7%, while
vascular polygons were significantly more frequent in rosacea, with a
specificity of 92.3%.
CONCLUSION: Dermoscopy may be a useful support to distinguish SLE malar rash and
erythematotelangiectatic rosacea by showing peculiar features. |
What is the mechanism of action of rogaratinib? | Rogaratinib is a highly potent and selective small-molecule pan-fibroblast growth factor receptor (FGFR) inhibitor (FGFR1-4) for oral application currently being investigated in phase 1 clinical trials for the treatment of cancer. | Rogaratinib (BAY 1163877) is a highly potent and selective small-molecule
pan-fibroblast growth factor receptor (FGFR) inhibitor (FGFR1-4) for oral
application currently being investigated in phase 1 clinical trials for the
treatment of cancer. In this publication, we report its discovery by de novo
structure-based design and medicinal chemistry optimization together with its
pharmacokinetic profile. Aberrant activation in fibroblast growth factor signaling has been implicated in
the development of various cancers, including squamous cell lung cancer,
squamous cell head and neck carcinoma, colorectal and bladder cancer. Thus,
fibroblast growth factor receptors (FGFRs) present promising targets for novel
cancer therapeutics. Here, we evaluated the activity of a novel pan-FGFR
inhibitor, rogaratinib, in biochemical, cellular and in vivo efficacy studies in
a variety of preclinical cancer models. In vitro kinase activity assays
demonstrate that rogaratinib potently and selectively inhibits the activity of
FGFRs 1, 2, 3 and 4. In line with this, rogaratinib reduced proliferation in
FGFR-addicted cancer cell lines of various cancer types including lung, breast,
colon and bladder cancer. FGFR and ERK phosphorylation interruption by
rogaratinib treatment in several FGFR-amplified cell lines suggests that the
anti-proliferative effects are mediated by FGFR/ERK pathway inhibition.
Furthermore, rogaratinib exhibited strong in vivo efficacy in several cell line-
and patient-derived xenograft models characterized by FGFR overexpression. The
observed efficacy of rogaratinib strongly correlated with FGFR mRNA expression
levels. These promising results warrant further development of rogaratinib and
clinical trials are currently ongoing (ClinicalTrials.gov Identifiers:
NCT01976741, NCT03410693, NCT03473756). BACKGROUND: The clinical activity of fibroblast growth factor receptor (FGFR)
inhibitors seems restricted to cancers harbouring rare FGFR genetic aberrations.
In preclinical studies, high tumour FGFR mRNA expression predicted response to
rogaratinib, an oral pan-FGFR inhibitor. We aimed to assess the safety, maximum
tolerated dose, recommended phase 2 dose, pharmacokinetics, and preliminary
clinical activity of rogaratinib.
METHODS: We did a phase 1 dose-escalation and dose-expansion study of
rogaratinib in adults with advanced cancers at 22 sites in Germany, Switzerland,
South Korea, Singapore, Spain, and France. Eligible patients were aged 18 years
or older, and were ineligible for standard therapy, with an Eastern Cooperative
Oncology Group performance status of 0-2, a life expectancy of at least 3
months, and at least one measurable or evaluable lesion according to Response
Evaluation Criteria in Solid Tumors (RECIST) version 1.1. During dose
escalation, rogaratinib was administered orally twice daily at 50-800 mg in
continuous 21-day cycles using a model-based dose-response analysis (continuous
reassessment method). In the dose-expansion phase, all patients provided an
archival formalin-fixed paraffin-embedded (FFPE) tumour biopsy or consented to a
new biopsy at screening for the analysis of FGFR1-3 mRNA expression. In the
dose-expansion phase, rogaratinib was given at the recommended dose for
expansion to patients in four cohorts: urothelial carcinoma, head and neck
squamous-cell cancer (HNSCC), non-small-cell lung cancer (NSCLC), and other
solid tumour types. Primary endpoints were safety and tolerability,
determination of maximum tolerated dose including dose-limiting toxicities and
determination of recommended phase 2 dose, and pharmacokinetics of rogaratinib.
Safety analyses were reported in all patients who received at least one dose of
rogaratinib. Patients who completed cycle 1 or discontinued during cycle 1 due
to an adverse event or dose-limiting toxicity were included in the evaluation of
recommended phase 2 dose. Efficacy analyses were reported for all patients who
received at least one dose of study drug and who had available post-baseline
efficacy data. This ongoing study is registered with ClinicalTrials.gov, number
NCT01976741, and is fully recruited.
FINDINGS: Between Dec 30, 2013, and July 5, 2017, 866 patients were screened for
FGFR mRNA expression, of whom 126 patients were treated (23 FGFR mRNA-unselected
patients in the dose-escalation phase and 103 patients with FGFR
mRNA-overexpressing tumours [52 patients with urothelial carcinoma, eight
patients with HNSCC, 20 patients with NSCLC, and 23 patients with other tumour
types] in the dose-expansion phase). No dose-limiting toxicities were reported
and the maximum tolerated dose was not reached; 800 mg twice daily was
established as the recommended phase 2 dose and was selected for the
dose-expansion phase. The most common adverse events of any grade were
hyperphosphataemia (in 77 [61%] of 126 patients), diarrhoea (in 65 [52%]), and
decreased appetite (in 48 [38%]); and the most common grade 3-4 adverse events
were fatigue (in 11 [9%] of 126 patients) and asymptomatic increased lipase (in
10 [8%]). Serious treatment-related adverse events were reported in five
patients (decreased appetite and diarrhoea in one patient with urothelial
carcinoma, and acute kidney injury [NSCLC], hypoglycaemia [other solid tumours],
retinopathy [urothelial carcinoma], and vomiting [urothelial carcinoma] in one
patient each); no treatment-related deaths occurred. Median follow-up after
cessation of treatment was 32 days (IQR 25-36 days). In the expansion cohorts,
15 (15%; 95% CI 8·6-23·5) out of 100 evaluable patients achieved an objective
response, with responses recorded in all four expansion cohorts (12 in the
urothelial carcinoma cohort and one in each of the other three cohorts), and in
ten (67%) of 15 FGFR mRNA-overexpressing tumours without apparent FGFR genetic
aberration.
INTERPRETATION: Rogaratinib was well tolerated and clinically active against
several types of cancer. Selection by FGFR mRNA expression could be a useful
additional biomarker to identify a broader patient population who could be
eligible for FGFR inhibitor treatment.
FUNDING: Bayer AG. |
Which epigenetic mark is deposited by PRC2? | H3K27me3 is the major histone methyltransferase activity of PRC2. | Organization of chromatin by epigenetic mechanisms is essential for establishing
and maintaining cellular identity in developing and adult organisms. A key
question that remains unresolved about this process is how epigenetic marks are
transmitted to the next cell generation during cell division. Here we provide a
model to explain how trimethylated Lys 27 of histone 3 (H3K27me3), which is
catalysed by the EZH2-containing Polycomb Repressive Complex 2 (PRC2), is
maintained in proliferating cells. We show that the PRC2 complex binds to the
H3K27me3 mark and colocalizes with this mark in G1 phase and with sites of
ongoing DNA replication. Efficient binding requires an intact trimeric PRC2
complex containing EZH2, EED and SUZ12, but is independent of the catalytic SET
domain of EZH2. Using a heterologous reporter system, we show that transient
recruitment of the PRC2 complex to chromatin, upstream of the transcriptional
start site, is sufficient to maintain repression through endogenous PRC2 during
subsequent cell divisions. Thus, we suggest that once the H3K27me3 is
established, it recruits the PRC2 complex to maintain the mark at sites of DNA
replication, leading to methylation of H3K27 on the daughter strands during
incorporation of newly synthesized histones. This mechanism ensures maintece
of the H3K27me3 epigenetic mark in proliferating cells, not only during DNA
replication when histones synthesized de novo are incorporated, but also outside
S phase, thereby preserving chromatin structure and transcriptional programs. RATIONALE: Epigenetic marks are crucial for organogenesis, but their role in
heart development is poorly understood. Polycomb repressive complex 2 (PRC2)
trimethylates histone H3 at lysine 27, which establishes H3K27me3 repressive
epigenetic marks that promote tissue-specific differentiation by silencing
ectopic gene programs.
OBJECTIVE: We studied the function of PRC2 in murine heart development using a
tissue-restricted conditional inactivation strategy.
METHODS AND RESULTS: Inactivation of the PRC2 subunit Ezh2 by Nkx2-5(Cre)
(Ezh2(NK)) caused lethal congenital heart malformations, namely, compact
myocardial hypoplasia, hypertrabeculation, and ventricular septal defect.
Candidate and genome-wide RNA expression profiling and chromatin
immunoprecipitation analyses of Ezh2(NK) heart identified genes directly
repressed by EZH2. Among these were the potent cell cycle inhibitors Ink4a/b
(inhibitors of cyclin-dependent kinase 4 A and B), the upregulation of which was
associated with decreased cardiomyocyte proliferation in Ezh2(NK).
EZH2-repressed genes were enriched for transcriptional regulators of
noncardiomyocyte expression programs such as Pax6, Isl1, and Six1. EZH2 was also
required for proper spatiotemporal regulation of cardiac gene expression,
because Hcn4, Mlc2a, and Bmp10 were inappropriately upregulated in ventricular
RNA. PRC2 was also required later in heart development, as indicated by
cardiomyocyte-restricted TNT-Cre inactivation of the PRC2 subunit Eed. However,
Ezh2 inactivation by TNT-Cre did not cause an overt phenotype, likely because of
functional redundancy with Ezh1. Thus, early Ezh2 inactivation by Nk2-5(Cre)
caused later disruption of cardiomyocyte gene expression and heart development.
CONCLUSIONS: Our study reveals a previously undescribed role of EZH2 in
regulating heart formation and shows that perturbation of the epigenetic
landscape early in cardiogenesis has sustained disruptive effects at later
developmental stages. The silencing of large chromosomal regions by epigenetic mechanisms has been
reported to occur frequently in cancer. Epigenetic marks, such as histone
methylation and acetylation, are altered at these loci. However, the mechanisms
of formation of such aberrant gene clusters remain largely unknown. Here, we
show that, in cancer cells, the epigenetic remodeling of chromatin into
hypoacetylated domains covered with histone H3K27 trimethylation is paralleled
by changes in higher-order chromatin structures. Using fluorescence in situ
hybridization, we demonstrate that regional epigenetic silencing corresponds to
the establishment of compact chromatin domains. We show that gene repression is
tightly correlated to the state of chromatin compaction and not to the levels of
H3K27me3-its removal through the knockdown of EZH2 does not induce significant
gene expression nor chromatin decompaction. Moreover, transcription can occur
with intact high-H3K27me3 levels; treatment with histone deacetylase inhibitors
can relieve chromatin compaction and gene repression, without altering H3K27me3
levels. Our findings imply that compaction and subsequent repression of large
chromatin domains are not direct consequences of PRC2 deregulation in cancer
cells. By challenging the role of EZH2 in aberrant gene silencing in cancer,
these findings have therapeutical implications, notably for the choice of
epigenetic drugs for tumors with multiple regional epigenetic alterations. During hippocampal neuron differentiation, the expression of critical inducers
of non-neuronal cell lineages must be efficiently silenced. Runx2 transcription
factor is the master regulator of mesenchymal cells responsible for
intramembranous osteoblast differentiation and formation of the craniofacial
bone tissue that surrounds and protects the central nervous system (CNS) in
mammalian embryos. The molecular mechanisms that mediate silencing of the Runx2
gene and its downstream target osteogenic-related genes in neuronal cells have
not been explored. Here, we assess the epigenetic mechanisms that mediate
silencing of osteoblast-specific genes in CNS neurons. In particular, we address
the contribution of histone epigenetic marks and histone modifiers on the
silencing of the Runx2/p57 bone-related isoform in rat hippocampal tissues at
embryonic to adult stages. Our results indicate enrichment of repressive
chromatin histone marks and of the Polycomb PRC2 complex at the Runx2/p57
promoter region. Knockdown of PRC2 H3K27-methyltransferases Ezh2 and Ezh1, or
forced expression of the Trithorax/COMPASS subunit Wdr5 activates Runx2/p57 mRNA
expression in both immature and mature hippocampal cells. Together these results
indicate that complementary epigenetic mechanisms progressively and efficiently
silence critical osteoblastic genes during hippocampal neuron differentiation. Precise expression patterns of genes in time and space are essential for proper
development of multicellular organisms. Dynamic chromatin conformation and
spatial organization of the genome constitute a major step in this regulation to
modulate developmental outputs. Polycomb repressive complexes (PRCs) mediate
stable or flexible gene repression in response to internal and environmental
cues. In Arabidopsis thaliana, LHP1 co-localizes with H3K27me3 epigenetic marks
throughout the genome and interacts with PRC1 and PRC2 members as well as with a
long noncoding RNA. Here, we show that LHP1 is responsible for the spreading of
H3K27me3 towards the 3' end of the gene body. We also identified a subset of
LHP1-activated genes and demonstrated that LHP1 shapes local chromatin topology
in order to control transcriptional co-regulation. Our work reveals a general
role of LHP1 from local to higher conformation levels of chromatin configuration
to determine its accessibility to define gene expression patterns. Aberrant PRC2 activity produces gene repressive epigenetic marks in multiple
diseases and led to identification of Ezh2 as a drug target. Recent studies have
shown that the epigenetic reader protein EED, associated with Ezh2 in PRC2, has
an additional function to stimulate the PRC2 activity after binding to H3K27me3.
Optimizing a compound known to block the H3K27me3 site in EED discovered by
in-house screening, Novartis scientists have now produced a compound that shows
durable tumor regression in a lymphoma xenograft model. |
Is Impetigo a viral infection that affects the skin? | No, impetigo is a highly contagious bacterial skin infection | This article reviews in detail the pathogenesis, clinical characteristics and
management of impetigo in children. Impetigo is the most common bacterial skin
infection of children. Most cases of nonbullous impetigo and all cases of
bullous impetigo are caused by Staphylococcus aureus. The remainder of cases of
nonbullous impetigo are due to group A beta hemolytic streptococci (GABHS).
GABHS colonize the skin directly by binding to sites on fibronectin that are
exposed by trauma. In contrast, S. aureus colonizes the nasal epithelium first;
from this reservoir, colonization of the skin occurs. Patients with recurrent
impetigo should be evaluated for carriage of S. aureus. Superficial, localized
impetigo may be treated successfully in more than 90% of cases with topical
application of mupirocin ointment. Impetigo that is widespread or involves
deeper tissues should be treated with a beta-lactamase-resistant oral
antibiotic. The choice of antibiotics is affected by the local prevalence of
resistance to erythromycin among strains of S. aureus, antibiotic cost and
availability, and issues of compliance. Impetigo is a common, superficial, bacterial infection of the skin characterized
by an inflamed and infected epidermis. The rarer variant, bullous impetigo, is
characterized by fragile fluid-filled vesicles and flaccid blisters and is
invariably caused by pathogenic strains of Staphylococcus aureus. Bullous
impetigo is at the mild end of a spectrum of blistering skin diseases caused by
a staphylococcal exfoliative toxin that, at the other extreme, is represented by
widespread painful blistering and superficial denudation (the staphylococcal
scalded skin syndrome). In bullous impetigo, the exfoliative toxins are
restricted to the area of infection, and bacteria can be cultured from the
blister contents. In staphylococcal scalded skin syndrome the exfoliative toxins
are spread hematogenously from a localized source causing widespread epidermal
damage at distant sites. Both occur more commonly in children under 5 years of
age and particularly in neonates. It is important to swab the skin for
bacteriological confirmation and antibiotic sensitivities and, in the case of
staphylococcal scalded skin syndrome, to identify the primary focus of
infection. Topical therapy should constitute either fusidic acid (Fucidin, Leo
Pharma Ltd) as a first-line treatment, or mupirocin (Bactroban, GlaxoSmithKline)
in proven cases of bacterial resistance. First-line systemic therapy is oral or
intravenous flucloxacillin (Floxapen, GlaxoSmithKline). Nasal swabs from the
patient and immediate relatives should be performed to identify asymptomatic
nasal carriers of Staphylococcus aureus. In the case of outbreaks on wards and
in nurseries, healthcare professionals should also be swabbed. Impetigo is a superficial, but contagious, bacterial infection of the skin that
predomitly affects children and is common in primary care. In UK general
practice, around half of the people with impetigo are treated with topical
fusidic acid. However, bacterial resistance to this antibacterial drug is
increasing. Here we discuss how patients with impetigo should be treated. Impetigo is the most common bacterial skin infection in children two to five
years of age. There are two principal types: nonbullous (70% of cases) and
bullous (30% of cases). Nonbullous impetigo, or impetigo contagiosa, is caused
by Staphylococcus aureus or Streptococcus pyogenes, and is characterized by
honey-colored crusts on the face and extremities. Impetigo primarily affects the
skin or secondarily infects insect bites, eczema, or herpetic lesions. Bullous
impetigo, which is caused exclusively by S. aureus, results in large, flaccid
bullae and is more likely to affect intertriginous areas. Both types usually
resolve within two to three weeks without scarring, and complications are rare,
with the most serious being poststreptococcal glomerulonephritis. Treatment
includes topical antibiotics such as mupirocin, retapamulin, and fusidic acid.
Oral antibiotic therapy can be used for impetigo with large bullae or when
topical therapy is impractical. Amoxicillin/clavulanate, dicloxacillin,
cephalexin, clindamycin, doxycycline, minocycline,
trimethoprim/sulfamethoxazole, and macrolides are options, but penicillin is
not. Natural therapies such as tea tree oil; olive, garlic, and coconut oils;
and Manuka honey have been anecdotally successful, but lack sufficient evidence
to recommend or dismiss them as treatment options. Treatments under development
include minocycline foam and Ozenoxacin, a topical quinolone. Topical
disinfectants are inferior to antibiotics and should not be used. Empiric
treatment considerations have changed with the increasing prevalence of
antibiotic-resistant bacteria, with methicillin-resistant S. aureus,
macrolide-resistant streptococcus, and mupirocin-resistant streptococcus all
documented. Fusidic acid, mupirocin, and retapamulin cover
methicillin-susceptible S. aureus and streptococcal infections. Clindamycin
proves helpful in suspected methicillin-resistant S. aureus infections.
Trimethoprim/sulfamethoxazole covers methicillin-resistant S. aureus infection,
but is inadequate for streptococcal infection. Because childhood rashes may be difficult to differentiate by appearance alone,
it is important to consider the entire clinical presentation to help make the
appropriate diagnosis. Considerations include the appearance and location of the
rash; the clinical course; and associated symptoms, such as pruritus or fever. A
fever is likely to occur with roseola, erythema infectiosum (fifth disease), and
scarlet fever. Pruritus sometimes occurs with atopic dermatitis, pityriasis
rosea, erythema infectiosum, molluscum contagiosum, and tinea infection. The key
feature of roseola is a rash presenting after resolution of a high fever,
whereas the distinguishing features in pityriasis rosea are a herald patch and a
bilateral and symmetric rash in a Christmas tree pattern. The rash associated
with scarlet fever usually develops on the upper trunk, then spreads throughout
the body, sparing the palms and soles. Impetigo is a superficial bacterial
infection that most commonly affects the face and extremities of children.
Erythema infectiosum is characterized by a viral prodrome followed by the
"slapped cheek" facial rash. Flesh-colored or pearly white papules with central
umbilication occur with molluscum contagiosum, a highly contagious viral
infection that usually resolves without intervention. Tinea is a common fungal
skin infection in children that affects the scalp, body, groin, feet, hands, or
nails. Atopic dermatitis is a chronic, relapsing inflammatory skin condition
that may present with a variety of skin changes. Skin infections account for a significant subset of dermatologic conditions of
childhood. Common cutaneous viral infections in children include warts,
molluscum contagiosum, hand-foot-and-mouth disease, and herpes simplex. Although
viral infections are self-limited and often only mildly symptomatic, they can
cause anxiety, embarrassment, and health care use. Recognition of their common
and atypical presentations is necessary to differentiate them from other skin
conditions of similar morphology. Impetigo, cellulitis, and abscess comprise the
majority of childhood bacterial skin infections and are treated with topical or
systemic antibiotics that cover group A Streptococcus and Staphylococcus aureus.
Common fungal dermatologic infections in children are oral and genital
candidiasis, tinea capitis, and tinea corporis. Management consists of topical
and systemic antifungals, including nystatin, triazoles, terbinafine,
griseofulvin, and imidazoles. Scabies is the most common parasitic skin
infection among children and is managed with topical permethrin. Although
serious illness is not common among children returning from international
travel, patients presenting with fever and rash, especially petechial or
hemorrhagic lesions, require thorough evaluation. Of the numerous reportable
conditions that present with childhood rash, tick-borne illnesses, measles,
rubella, and varicella are the most common. Streptococcus pyogenes is responsible for a wide variety of cutaneous infections
ranging from superficial impetigo to fulmit invasive necrotizing fasciitis.
Dysfunction of desmosomes is associated with the pathogenesis of cutaneous
diseases. We identified streptococcal pyrogenic exotoxin B (SpeB) as a
proteolytic factor that cleaves the extracellular domains of desmoglein 1 and 3.
In an epicutaneous infection model, lesional skin infected with an speB deletion
mutant were significantly smaller as compared to those caused by the wild-type
strain. Furthermore, immunohistological analysis indicated cleavage of
desmogleins that developed around the invasion site of the wild-type strain. In
contrast, the speB mutant was preferentially found on the epidermis surface
layer. Taken together, our findings provide evidence that SpeB-mediated
degradation of desmosomes has a pathogenic role in development of S. pyogenes
cutaneous infection. IMPORTANCE: Ozenoxacin, a novel topical antibacterial agent with potent
bactericidal activity against gram-positive bacteria, has been developed as a
cream with 1% active drug for the treatment of impetigo, a highly contagious
bacterial skin infection.
OBJECTIVES: To evaluate the efficacy, safety, and tolerability of ozenoxacin
cream, 1%, after 5-day twice-daily topical treatment in patients with impetigo.
DESIGN, SETTING, AND PARTICIPANTS: This randomized, double-blind,
vehicle-controlled clinical trial included patients 2 months or older with
impetigo who were enrolled at centers in 6 countries from June 2, 2014, through
May 30, 2015. Data were analyzed based on intention to treat from July 9 through
July 22, 2015.
INTERVENTIONS: Patients were randomized 1:1 to receive topical ozenoxacin or
placebo control.
MAIN OUTCOMES AND MEASURES: Efficacy was measured using the Skin Infection
Rating Scale and microbiological culture. Safety and tolerability were also
evaluated.
RESULTS: Among the 411 patients who received treatment (210 males [51.1%]; mean
[SD] age, 18.6 [18.3] years), ozenoxacin demonstrated superior clinical success
compared with placebo, which was evident after 5 days of therapy (112 of 206
[54.4%] vs 78 of 206 [37.9%]; P = .001). Ozenoxacin also demonstrated superior
microbiological success compared with placebo after 2 days of therapy (109 of
125 [87.2%] vs 76 of 119 [63.9%]; P = .002). Ozenoxacin was well tolerated, with
8 of 206 patients experiencing adverse effects, with only 1 of these potentially
related to the study treatment; none were serious.
CONCLUSIONS AND RELEVANCE: Topical ozenoxacin is effective and well tolerated in
the treatment of impetigo in patients 2 months and older. This effect is
demonstrated by rapid onset of response and superior clinical and
microbiological response compared with placebo. Topical ozenoxacin represents a
novel option for the treatment of impetigo.
TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT02090764. |
List diseases that are caused by the Meningococcus B? | The prevention of paediatric bacterial meningitis and septicaemia has recently entered a new era with the availability of two vaccines against capsular group B meningococcus | Sepsis and meningitis caused by serogroup B meningococcus are devastating
diseases of infants and young adults, which cannot yet be prevented by
vaccination. By genome mining, we discovered GNA1870, a new surface-exposed
lipoprotein of Neisseria meningitidis that induces high levels of bactericidal
antibodies. The antigen is expressed by all strains of N. meningitidis tested.
Sequencing of the gene in 71 strains representative of the genetic and
geographic diversity of the N. meningitidis population, showed that the protein
can be divided into three variants. Conservation within each variant ranges
between 91.6 to 100%, while between the variants the conservation can be as low
as 62.8%. The level of expression varies between strains, which can be
classified as high, intermediate, and low expressors. Antibodies against a
recombit form of the protein elicit complement-mediated killing of the
strains that carry the same variant and induce passive protection in the infant
rat model. Bactericidal titers are highest against those strains expressing high
yields of the protein; however, even the very low expressors are efficiently
killed. The novel antigen is a top candidate for the development of a new
vaccine against meningococcus. Meningitis and sepsis caused by serogroup B meningococcus are two severe
diseases that still cause significant mortality. To date there is no universal
vaccine that prevents these diseases. In this work, five antigens discovered by
reverse vaccinology were expressed in a form suitable for large-scale
manufacturing and formulated with adjuvants suitable for human use. The vaccine
adjuvanted by aluminum hydroxide induced bactericidal antibodies in mice against
78% of a panel of 85 meningococcal strains representative of the global
population diversity. The strain coverage could be increased to 90% and above by
the addition of CpG oligonucleotides or by using MF59 as adjuvant. The vaccine
has the potential to conquer one of the most devastating diseases of childhood. The prevention of paediatric bacterial meningitis and septicaemia has recently
entered a new era with the availability of two vaccines against capsular group B
meningococcus (MenB). Both of these vaccines are based on sub-capsular proteins
of the meningococcus, an approach that overcomes the challenges set by the
poorly immunogenic MenB polysaccharide capsule but adds complexity to predicting
and measuring the impact of their use. This review describes the development and
use of MenB vaccines to date, from the use of outer membrane vesicle (OMV)
vaccines in MenB outbreaks around the world, to emerging evidence on the
effectiveness of the newly available vaccines. While recent data from the United
Kingdom supports the potential for protein-based vaccines to provide direct
protection against MenB disease in immunised children, further research is
required to understand the breadth and duration of this protection. A more
detailed understanding of the impact of immunisation with these vaccines on
nasopharyngeal carriage of the meningococcus is also required, to inform both
their potential to induce herd immunity and to preferentially select for
carriage of strains not susceptible to vaccine-induced antibodies. Although a
full understanding of the potential impact of these vaccines will only be
possible with this additional information, the availability of new tools to
prevent the devastating effect of invasive MenB disease is a significant
breakthrough in the fight against childhood sepsis and meningitis. |
Should Lubeluzole be used for treatment of ischemic stroke? | No. Lubeluzole failed to consistently show an efficacy in the treatment of acute stroke and should not be used. | BACKGROUND AND PURPOSE: We aimed to assess the safety and efficacy of lubeluzole
in patients with a clinical diagnosis of acute (< 6 hours) ischemic stroke in
the carotid artery territory.
METHODS: A randomized, double-blind, placebo-controlled multicenter trial was
conducted in 232 patients. Because treatment was administered within 6 hours and
a CT scan was not mandatory before the start of treatment, 39 patients with
either an intracerebral hemorrhage or ischemic stroke in the vertebrobasilar
circulation were excluded from the primary efficacy analysis as prespecified in
the protocol. Of the 193 patients with acute ischemic stroke in the carotid
artery territory (target population), 61 received placebo, 66 lubeluzole 7.5 mg
over 1 hour followed by 10 mg/d for 5 days, and 66 lubeluzole 15 mg over 1 hour
followed by 20 mg/d for 5 days.
RESULTS: The trial, initially aimed at a patient inclusion of 270, was
terminated prematurely according to the advice of the Safety Committee because
of an imbalance in mortality between the treatment groups. Mortality rates at
the final follow-up of 28 days for placebo, lubeluzole 10 mg/d, and lubeluzole
20 mg/d were, respectively, 18%, 6%, and 35% in the target population, results
that were confirmed in the intent-to-treat population. Multivariate logistic
regression analysis showed that the lower mortality in the lubeluzole 10 mg/d
group was significantly in favor of the 10 mg/d treatment (P = .019). The higher
mortality rate in the 20 mg/d group could be explained, at least in part, by an
imbalance at randomization that led to a higher number of patients in that group
with severe ischemic stroke. A total of 26 of 66 patients (39%) who received
lubeluzole 10 mg/d had a score on the Barthel Index of > 70 at day 28,
indicating no or mild disability, compared with 21 of 61 (34%) in the placebo
group and 19 of 66 (29%) in the lubeluzole 20 mg/d group (P = NS).
CONCLUSIONS: In patients with acute ischemic stroke, the dosage regimen of 7.5
mg over 1 hour followed by 10 mg/d of intravenous lubeluzole is safe and
statistically significantly reduced mortality. Further clinical trials in a
larger number of patients are ongoing to confirm efficacy. BACKGROUND AND PURPOSE: Lubeluzole is a benzothiazole derivative that has shown
neuroprotective properties in different experimental models. This multicentre,
double-blind, placebo-controlled trial was conducted to assess the safety and
efficacy of lubeluzole in patients with an acute ischaemic stroke.
METHODS: Patients who presented with clinical signs and symptoms of acute
cerebral hemispheric ischaemic stroke were randomised to intravenous therapy
with placebo (n = 360) or lubeluzole 7.5 mg over 1 h followed by 10 mg/day for
up to 5 days (n = 365). Treatment was initiated within 6 h of symptom onset.
Mortality at 12 weeks was the primary end point. Secondary end points included
neurological status (European Stroke Scale), functional outcome (Barthel Index),
and disability level (Rankin Scale). The primary and secondary end points were
all analysed using the protocol-defined Cochran-Mantel-Haenszel's general
association test. An additional analysis, the logistic regression approach, that
included risk factors of age, baseline stroke severity and their interactions
with treatment, was used to analyze outcome measures at 3 months.
RESULTS: In the total ischaemic stroke population, the overall mortality rate at
3 months was similar for lubeluzole (21.0%) and placebo (21.4%). The logistic
regression model confirmed the effect of age on mortality risk, but showed that
this was independent of treatment. Treatment benefit was related to stroke
severity, as determined by the Clinical Global Impression rating, that is a
pronounced clinically significant reduction in mortality was noted in the
lubeluzole-treated patients for whom stroke severity was mild to moderate, but
not in those for whom it was severe. This was found on the basis of a post hoc
analysis not specified in the hypothesis. Lubeluzole did not increase morbidity
among stroke survivors, as measured by the European Stroke Scale, Barthel Index
and Rankin Scale. No safety concerns were seen with lubeluzole treatment.
CONCLUSIONS: In the overall study population, treatment with intravenous
lubeluzole within 6 h of the onset of ischaemic stroke did not affect mortality
or clinical outcome. Among patients with mild to moderate ischaemic stroke,
lubeluzole decreased mortality without increasing morbidity. BACKGROUND AND PURPOSE: This trial was a double-blind, placebo-controlled, phase
III trial with an 8-hour inclusion window to assess the efficacy and safety of
an intravenous loading dose of 7.5 mg followed by a daily intravenous dose of 10
mg lubeluzole for 5 days in acute ischemic stroke patients.
METHODS: A total of 1786 patients were randomized: 901 to lubeluzole and 885 to
placebo. Overall, 212 patients (23.5%) from the lubeluzole group and 213 (24.1%)
from the placebo group discontinued the trial prematurely. In the lubeluzole
group 201 patients (22.3%) discontinued because of adverse events compared with
193 patients (21.8%) in the placebo group.
RESULTS: The primary population for the efficacy analysis comprised the core
stroke patients (exclusion of older patients aged >75 years with severe stroke)
in the 0- to 6-hour inclusion time window. The primary efficacy parameter was a
3-category functional status (Barthel Index 70 to 100/0 to 70/vegetative, dead)
at week 12. In the lubeluzole group 207 patients (47.8%) were classified as
mildly dependent/independent at week 12, 131 (30.3%) were moderately/severely
dependent, and 95 (21.9%) were vegetative/dead. In the placebo group these
numbers were 221 (54.4%), 112 (27.6%), and 73 (18.0%), respectively. Logistic
regression analysis showed no statistically significant difference between the
treatment groups (P:=0.162). Additionally, for none of the secondary efficacy
parameters (mortality at week 12, modified Rankin score, total Barthel score)
was a statistically significant difference between the lubeluzole and placebo
groups obtained. There were no statistically significant differences between the
2 treatments for all treated patients, patients included within the 6- to 8-hour
window, and patients with severe strokes aged >75 years. Overall, of all treated
patients, 401 (22.5%) died: 203 (22.5%) in the lubeluzole group and 198 (22.4%)
with placebo. Of all subjects treated, 853 (95%) on lubeluzole and 826 (93%) on
placebo reported an adverse event during their treatment period or within the
next 2 days after discontinuation of treatment. The most frequently observed
adverse events were fever (25.9% lubeluzole; 23.4% placebo), constipation
(20.2%; 19.7%), and headache (17.6%; 21.2%). Imbalances were found for atrial
fibrillation (1.8% lubeluzole; 1.1% placebo) and QT prolongation (0.9%; 0.2%).
CONCLUSIONS: This study failed to show an efficacy of lubeluzole in the
treatment of acute stroke. On the other hand, lubeluzole treatment by the
current dosage schedule was not associated with a significant safety problem. BACKGROUND: Experimental studies have shown that ischaemic insults cause excess
release of excitatory amino acid (EAA) neurotransmitters, particularly
glutamate. Glutamate re-uptake is impaired under ischaemic conditions. In
preclinical models of stroke, antagonists of excitatory amino acids or of
glutamate release protect against ischaemic injury, even when administered after
the ischaemic insult. Lubeluzole is a benzothiazole derivative that has shown
neuroprotective properties in different experimental models inhibiting glutamate
release, nitric oxide (NO) synthesis and blocking voltage-gated Na+ and Ca2+ ion
channels.
OBJECTIVES: The objective of this review is to assess the effectiveness and
safety of lubeluzole given in the acute phase of acute ischaemic stroke.
SEARCH STRATEGY: The Cochrane Stroke Group trials register was searched.
Additional searches of Cochrane Controlled Trials Register (CENTRAL/CCTR),
Medline, Embase, Pascal BioMed (1996-2001) and Current Contents CCSearch reg 7
Editions (1996-2001) were made to supplement the Stroke Group general strategy.
We contacted Janssen Research Foundation to identify further studies.
SELECTION CRITERIA: All randomised unconfounded trials comparing intravenous
lubeluzole with placebo or open control in patients with a clinical syndrome
definitely considered as an acute stroke in whom CT scanning showed an infarct
or was normal.
DATA COLLECTION AND ANALYSIS: Two reviewers independently selected trials for
inclusion, assessed trial quality and extracted the data.
MAIN RESULTS: Five trials involving a total of 3,510 patients were included. The
quality of the trials did not vary considerably. Sensitivity/subgroups analysis
was not completely performed because of lack of data. Lubeluzole given at the
doses of 5, 10 and 20 mg/day for 5 days was tested against a placebo-control
group. There was no evidence that Lubeluzole given at any dose either reduced
the odds of death from all causes (OR=0.93, 95% CI 0.79-1.09) or reduced the
odds of being dead or dependent at the end of follow-up (OR=1.04, 95% CI
0.91-1.19). On the other hand, given at any dose, Lubeluzole was associated with
a significant excess of heart-conduction disorders (Q-T prolonged > 450 msec) at
the end of follow-up (OR=1.43, 95% CI 1.09-1.87).
REVIEWER'S CONCLUSIONS: Lubeluzole, given in the acute phase of ischaemic
stroke, is not associated with a significant reduction of death or dependency at
the end of scheduled follow-up period but seems to be associated with a
significant increase of heart-conduction disorders (Q-T prolonged >450 msec). BACKGROUND/AIMS: Lubeluzole is a benzothiazole derivative that has shown
neuroprotective properties in preclinical models of ischemic stroke. However,
clinical research on lubeluzole is now at a standstill, since lubeluzole seems
to be associated with the acquired long QT syndrome and ventricular arrhythmias.
Since the cardiac cellular effects of lubeluzole have not been described thus
far, an explanation for the lubeluzole-induced QT interval prolongation is
lacking.
METHODS: We tested the affinity of lubeluzole, its etiomer, and the racemate
for hERG channel using the patch-clamp technique. We synthesized and tested two
simplified model compounds corresponding to two moieties included in the
lubeluzole structure. The obtained experimental results were rationalized by
docking simulation on the recently reported cryo-electron microscopy (cryo-EM)
structure of hERG. Group efficiency analysis was performed in order to
individuate the fragment most contributing to binding.
RESULTS: We found that lubeluzole and its R etiomer are highly potent
inhibitors of human ether-ago-go-related gene (hERG) channel with an IC50 value
of 12.9 ± 0.7 nM and 11.3 ± 0.8 nM, respectively. In the presence of lubeluzole,
steady-state activation and inactivation of hERG channel were shifted to more
negative potentials and inactivation kinetics was accelerated. Mutations of
aromatic residues (Y652A and F656A) in the channel inner cavity significantly
reduced the inhibitory effect of lubeluzole. Molecular docking simulations
performed on the near atomic resolution cryo-electron microscopy structures of
hERG supported the role of Y652 and F656 as the main contributors to high
affinity binding. Group efficiency analysis indicated that both
1,3-benzothiazol-2-amine and 3-aryloxy-2-propanolamine moieties contribute to
drug binding with the former giving higher contribution.
CONCLUSIONS: This study suggests the possibility to modulate lubeluzole hERG
blockade by introducing suitable substituents onto one or both constituting
portions of the parent compound in order to either reduce potency (i. e.
torsadogenic potential) or potentiate affinity (useful for class III
antiarrhythmic and anticancer agent development). |
What is vivotif? | Vivotif(r) is an oral live attenuated vaccine which contains a mutated strain of Salmonella (Ty21a) and reproduces the natural infection. The vaccine was first licensed in Europe in 1983 and in the US in 1989, and over the years it has proved efficacious and safe. It is indicated for adults and children from 5 years of age upwards. Specifically, in the most developed countries, vaccination is suggested for highrisk population groups and particularly for international travellers to destinations where the risk of contracting typhoid fever is high. Vivotif(r) appears to be a powerful means of disease prevention, the importance of which is highlighted by the spread of antibiotic-resistant strains of Salmonella typhy (S. typhi). | Cases of diarrhoeal disease number from 1.7 to 5 billion per year worldwide. One
of the main causes of diarrhoeal disease is typhoid fever, which is a
potentially life-threatening multi-systemic illness. According to the most
recent estimates, a total of 26.9 million typhoid fever episodes occurred in
2010. The geographical distribution of the disease differs widely; in developed
countries, the incidence rate per 100,000 per year varies from < 0.1 to 0.3, and
the disease mainly affects people who travel to endemic areas located in low-
and middle-income countries. Low- and middle-income countries are mainly
affected owing to the lack of clean water and proper sanitation. In the fight
against this plague, prevention is fundamental, and vaccination against typhoid
is an effective measure. Vivotif® is an oral live attenuated vaccine which
contains a mutated strain of Salmonella (Ty21a) and reproduces the natural
infection. The vaccine was first licensed in Europe in 1983 and in the US in
1989, and over the years it has proved efficacious and safe. It is indicated for
adults and children from 5 years of age upwards. Specifically, in the most
developed countries, vaccination is suggested for highrisk population groups and
particularly for international travellers to destinations where the risk of
contracting typhoid fever is high. It must also be borne in mind that
international travel is increasing. Indeed, international tourist arrivals
totalled 1,184 million in 2015 and, on the basis of current trends,
international travel is expected to grow by 3-4% in 2017. Vivotif® appears to be
a powerful means of disease prevention, the importance of which is highlighted
by the spread of antibiotic-resistant strains of Salmonella typhy (S. typhi). |
List types of cancer where TBC1 domain family member 16 (TBC1D16) is involved | TBC1D16 is a predictive marker for favorable prognosis of Epithelial ovarian cancer (EOC). In addition, a short isoform of TBC1D16 (TBC1D16-47KD) exacerbates melanoma growth and metastasis both in vitro and in vivo. | Author information:
(1)Cancer Epigenetics and Biology Program, Bellvitge Biomedical Research
Institute, L'Hospitalet, Barcelona, Catalonia, Spain.
(2)Molecular Oncology Group, Cancer Research UK Manchester Institute,
Manchester, UK.
(3)Translational Research Laboratory, Catalan Institute of Oncology, Bellvitge
Biomedical Research Institute, L'Hospitalet, Barcelona, Catalonia, Spain.
(4)Department of Pathological Anatomy, Bellvitge University Hospital, Bellvitge
Biomedical Research Institute, L'Hospitalet, Barcelona, Catalonia, Spain.
(5)Medical Oncology Service, Catalan Institute of Oncology, Germans Trias i
Pujol University Hospital, Badalona, Catalonia, Spain.
(6)Pathology Department, Germans Trias i Pujol University Hospital, Badalona,
Catalonia, Spain.
(7)Medical Oncology Service, Vall d'Hebron University Hospital, Barcelona,
Catalonia, Spain.
(8)Dermatology Service, Hospital La Fe, Universidad de Valencia, Valencia,
Spain.
(9)Medical Oncology Service, Hospital General, Valencia, Spain.
(10)Department of Pathology, University Hospital of Uppsala, Uppsala, Sweden.
(11)Translational Cell &Tissue Pathology, Katholieke Universiteit Leuven,
Leuven, Belgium.
(12)University College Dublin School of Biomolecular and Biomedical Science,
University College Dublin Conway Institute, University College Dublin, Belfield,
Dublin, Ireland.
(13)Center for Melanoma, Massachusetts General Hospital Cancer Center, Boston,
Massachusetts.
(14)Cancer Genome Project, Wellcome Trust Sanger Institute, Hinxton, Cambridge,
UK.
(15)University of Manchester, Christie National Health Service Foundation Trust,
Manchester, UK.
(16)1] Cancer Epigenetics and Biology Program, Bellvitge Biomedical Research
Institute, L'Hospitalet, Barcelona, Catalonia, Spain. [2] Department of
Physiological Sciences II, School of Medicine, University of Barcelona,
Barcelona, Catalonia, Spain. [3] Institucio Catalana de Recerca i Estudis
Avançats, Barcelona, Catalonia, Spain. Epithelial ovarian cancer (EOC) is the most lethal gynecologic maligcy with
high recurrence and poor prognosis duo to the lack of effective biomarkers. TBC1
domain family member 16 (TBC1D16), a GTPase-activating protein, is involved in
regulating intracellular trafficking in tumorigenesis and metastasis. However,
the clinical significance of TBC1D16 in EOC remains unknown. In the present
study, we investigated the expression and prognostic significance of TBC1D16 in
EOC and its relationship with the expression of vascular endothelial growth
factor (VEGF). The tissue specimens included 156 histologically confirmed EOC
and 30 normal ovarian tissues. The expression of TBC1D16 and VEGF was detected
by immunohistochemistry (IHC), and the immunoreactive score was calculated with
signal intensity and percentage of positive cells. IHC results showed that
TBC1D16 and VEGF were both mainly localized in cytoplasm of epithelial cells in
normal ovarian tissues and were expressed in cancer cells. Based on the
immunoreactive score, TBC1D16 expression in EOC was categorized as "high
expression," compared with normal ovarian tissues (P < 0.05). The Chi-square
test showed that high TBC1D16 expression was related to advanced pT stages (P =
0.029), but not correlated with other clinical features. Moreover, the TBC1D16
expression was significantly higher in EOC specimens with low VEGF expression (P
< 0.001). Importantly, in both univariate and multivariate survival analyses,
high expression of TBC1D16 was significantly correlated with good overall
survival (OS). In conclusion, TBC1D16 is a predictive marker for favorable
prognosis of EOC. BACKGROUND: Characteristic DNA methylation differences have been identified
between primary and metastatic melanomas at EBF3 and/or TBC1D16 gene loci. To
further evaluate whether these epigenetic changes may act more generally as
drivers of tumour onset and metastasis, we have investigated DNA methylation
changes involving EBF3 and TBC1D16 in additional publicly available data of
multiple different tumour types.
RESULTS: Promoter hypermethylation and gene body hypomethylation of EBF3 were
observed in a number of metastatic tumour types, when compared to normal or
primary tumour tissues, as well as in tumour vs normal tissues and in a
colorectal primary/metastasis pair, although not all tumour samples or
primary/metastasis cancer pairs exhibited altered patterns of EBF3 methylation.
In addition, hypomethylation of TBC1D16 was observed in multiple tumours,
including a breast cancer primary/metastasis pair, and to a lesser degree in
melanoma, although again not all tumours or cancer primary/metastasis pairs
exhibited altered patterns of methylation.
CONCLUSIONS: These findings suggest characteristic DNA methylation changes in
EBF3 and TBC1D16 are relatively common tumour-associated epigenetic events in
multiple tumour types, which is consistent with a potential role as more general
drivers of tumour progression. |
What does osanetant and talnetant have in common? | Osanetant and talnetant are selective NK3 antagonists. Preclinical and Phase II clinical results of osanetant and talnetant in schizophrenic patients have indicated that NK(3) antagonists may provide significant improvement of the positive symptoms and cognitive impairment associated with this disorder. | INTRODUCTION: The neurokinin 3 (NK(3)) receptor is a GPCR that has been shown to
modulate monoaminergic systems within regions of the brain implicated in
schizophrenia. Preclinical and Phase II clinical results of osanetant and
talnetant in schizophrenic patients have indicated that NK(3) antagonists may
provide significant improvement of the positive symptoms and cognitive
impairment associated with this disorder. Recent findings have also indicated
that neurokinin B (NKB)-NK(3) signaling plays a key role in the hypothalamic
regulation of reproduction in humans.
AREAS COVERED: This review article discusses the latest medicinal chemistry
strategies used to derive novel NK(3) receptor antagonists which have been
patented during the period 2005 - 2010.
EXPERT OPINION: Since the report of a beneficial effect of osanetant in
schizophrenic patients, major pharmaceutical companies have been involved in
this field, leading to a very large number of patent applications disclosed.
Nevertheless, only three NK(3) selective antagonists entered into Phase II, but
were then terminated for various reasons. Currently, the main challenge to move
forward a selective NK(3) antagonist into the clinic would be to define a safety
margin between the desired therapeutic effect and the effect on testosterone
levels. The involvement of NKB-NK(3) signaling in reproduction in humans may
also lead to new exciting indications, such as treatment for sex
steroid-sensitive cancers of breast and prostate. The NK3 receptor is a GPCR that is prominently expressed in limbic areas of the
brain, many of which have been implicated in schizophrenia. Phase II clinical
trials in schizophrenia with two selective NK3 antagonists (osanetant and
talnetant) have demonstrated significant improvement in positive symptoms. The
objective of this study was to characterize the properties of a novel dual
NK2/NK3 antagonist, RO5328673. [(3)H]RO5328673 bound to a single saturable site
on hNK2, hNK3 and gpNK3 with high-affinity. RO5328673 acted as an insurmountable
antagonist at both human and guinea-pig NK3 receptors in the [(3)H]IP
accumulation assay. In binding kinetic analyses, [(3)H]RO5328673 had fast
association and dissociation rates at hNK2 while it had a fast association rate
and a remarkably slow dissociation rate at gp and hNK3. In electrophysiological
recordings of gp SNpc, RO5328673 inhibited the senktide-induced potentiation of
spontaneous activity of dopaminergic neurons with an insurmountable mechanism of
action. RO5328673 exhibited in-vivo activity in gerbils, robustly reversing the
senktide-induced locomotor activity. The TM2 residue gpNK3-A114(2.58) (threonine
in all other species) was identified as the critical residue for the RO5328673's
slower dissociation kinetics and stronger insurmountable mode of antagonism in
the guinea-pig as compared to hNK3-T139(2.58). Using site-directed mutagenesis,
[(3)H]RO5328673 binding and rhodopsin-based modeling, the important molecular
determits of the RO5328673-binding pocket of hNK3 were determined. A
comparison of the RO5328673-binding pocket with that of osanetant showed that
two antagonists have similar contact sides on hNK3 binding crevice except for
three mutations V95L(1.42), Y247W(5.38), V255I(5.46), which behaved differently
between interacting modes of two antagonists in hNK3. |
List SLC25A46-related pathologies | The mitochondrial protein SLC25A46 has been recently identified as a novel pathogenic cause in a wide spectrum of neurological diseases, including inherited optic atrophy, Charcot-Marie-Tooth type 2, Leigh syndrome, progressive myoclonic ataxia and lethal congenital pontocerebellar hypoplasia. | The mitochondrial protein SLC25A46 has been recently identified as a novel
pathogenic cause in a wide spectrum of neurological diseases, including
inherited optic atrophy, Charcot-Marie-Tooth type 2, Leigh syndrome, progressive
myoclonic ataxia and lethal congenital pontocerebellar hypoplasia. SLC25A46 is
an outer membrane protein, member of the Solute Carrier 25 (SLC25) family of
nuclear genes encoding mitochondrial carriers, with a role in mitochondrial
dynamics and cristae maintece. Here we identified a loss-of-function mutation
in the Slc25a46 gene that causes lethal neuropathology in mice. Mutant mice
manifest the main clinical features identified in patients, including ataxia,
optic atrophy and cerebellar hypoplasia, which were completely rescued by
expression of the human ortholog. Histopathological analysis revealed previously
unseen lesions, most notably disrupted cytoarchitecture in the cerebellum and
retina and prominent abnormalities in the neuromuscular junction. A distinct
lymphoid phenotype was also evident. Our mutant mice provide a valid model for
understanding the mechanistic basis of the complex SLC25A46-mediated
pathologies, as well as for screening potential therapeutic interventions. |
What is the target of galcanezumab? | Galcanezumab is a monoclonal antibody against calcitonin gene-related peptide (CGRP), is one of a novel class of new medicines for migraine prevention. | Conflict of interest statement: Conflict of Interest Disclosures: Drs
Skljarevski, Oakes, Zhang, Ferguson, Martinez, Camporeale, Johnson, Shan,
Carter, and Schacht are full-time employees of Eli Lilly and Company and/or one
of its subsidiaries, and are stockholders. Dr Goadsby reports receiving
consultant fees from Allergan, Amgen, and Eli-Lilly and Company; and personal
fees from Akita Biomedical, Alder Biopharmaceuticals, Autonomic Technologies
Inc, Avanir Pharma, Cipla Ltd, Colucid Pharmaceuticals, Ltd, Dr Reddy's
Laboratories, eNeura, Electrocore LLC, Novartis, Pfizer Inc, Promius Pharma,
Quest Diagnostics, Scion, Teva Pharmaceuticals, Trigemina Inc; MedicoLegal work,
Journal Watch, UptoDate, and Oxford University Press. In addition, Dr Goadsby
has a patent magnetic stimulation for headache pending assigned to eNeura. Dr
Dodick has received compensation from serving on advisory boards and/or
consulting within the past 5 years for Allergan, Amgen, Alder, Arteaus, Pfizer,
Colucid, Merck, NuPathe, Eli Lilly and Company, Autonomic Technologies, Ethicon
J&J, Zogenix, Supernus, Labrys, Boston Scientific, Medtronic, St Jude,
Bristol-Myers Squibb, Lundbeck, Impax, MAP, Electrocore, Tonix, Novartis, Teva,
Alcobra, Zosano, Insys, GBS/Nocira, Acorda, eNeura, Charleston Laboratories,
Gore, Biohaven, Bioventric, Magellan, Theranica, Xenon, and Dr Reddy’s/Promius
Pharma. Dr Dodick owns equity in Epien, GBS/Nocira, Second Opinion, Healint, and
Theranica. Dr Dodick has received funding for travel, speaking, editorial
activities, or royalty payments from IntraMed, SAGE Publishing, Sun Pharma,
Allergan, Oxford University Press, American Academy of Neurology, American
Headache Society, West Virginia University Foundation, Canadian Headache
Society, HealthLogix, Universal Meeting Management, WebMD, UptoDate, Medscape,
Oregon Health Science Center, Albert Einstein University, University of Toronto,
Starr Clinical, Decision Resources, Synergy, MedNet LLC, Peer View Institute for
Medical Education, Medicom, Chameleon Communications, Academy for Continued
Healthcare Learning, Haymarket Medical Education, Global Scientific
Communications, HealthLogix, Miller Medical, MeetingLogiX, and Wiley Blackwell.
Dr Dodick, through his employer, has consulting use agreements with
NeuroAssessment Systems and Myndshft. He holds board of director positions with
King-Devick Technologies and Epien Inc. He holds the following Patent
17189376.1-1466:vTitle: Botulinum Toxin Dosage Regimen for Chronic Migraine
Prophylaxis (no compensation). No other disclosures are reported. Background Safety findings from a Phase 2b study of galcanezumab, a humanized
monoclonal antibody against calcitonin gene-related peptide, for prevention of
migraine (NCT02163993) are reported here. Methods Patients aged 18-65 years with
episodic migraine were evaluated in this multicenter, double-blind, randomized
study. After randomization, 410 patients were administered 5, 50, 120 or 300 mg
of galcanezumab or placebo subcutaneously once every 4 weeks for 12 weeks,
followed by a post-treatment off-drug period lasting 12 weeks. Results
Treatment-emergent adverse events (TEAEs) were primarily rated as mild to
moderate. Serious adverse events reported in galcanezumab dose groups were
appendicitis, Crohn's disease, suicidal ideation, and congenital ankyloglossia
in an infant of a paternal pregcy; each of these were reported by one
patient. Adverse events leading to discontinuation with galcanezumab treatment
were abdominal pain, visual impairment, and upper limb fracture, each reported
by one patient. Treatment-emergent injection-site reactions were reported
significantly more frequently ( p = 0.013) with galcanezumab (13.9%) than with
placebo (5.8%). Injection-site pain was the most common injection-site reaction
(galcanezumab 11.4%; placebo 2.9%, p = 0.004). Upper respiratory tract infection
(galcanezumab 10.0%; placebo 8.8%) and nasopharyngitis (galcanezumab 7.0%;
placebo 2.2%) also occurred more frequently with galcanezumab treatment.
Potential hypersensitivity events were reported at similar frequencies in
galcanezumab (3.3%) and placebo (5.1%) groups. Incidence of treatment-emergent
anti-drug antibodies in galcanezumab dose groups (4.6% of patients during
treatment period) did not appear to have any meaningful effects on safety, the
pharmacokinetics of galcanezumab, or its ability to bind to the target ligand.
Conclusion The results from this 3-month Phase 2b study support the initiation
of larger Phase 3 trials of longer duration. PURPOSE OF REVIEW: Monoclonal antibodies (mAbs) targeting the
calcitonin-gene-related peptide (CGRP) pathway have been developed for episodic
and chronic migraine prevention, either through binding the CGRP ligand
(eptinezumab, fremanezumab, galcanezumab) or the CGRP receptor (erenumab). We
provide an update on published Phase 2 and Phase 3 trials, safety/tolerability
data, pharmacokinetics and mechanism of action of these biologicals.
RECENT FINDINGS: The efficacy data from Phase 2 trials are corroborated by those
from published Phase 3 trials, with a multitude of publications expected in
2018. Review of safety data concluded there was no difference in total adverse
events or main adverse events (including upper respiratory tract infection,
nasopharyngitis, nausea, injection-site pain and back pain) between the mAbs and
placebo injections except apparently for dizziness. The site of action of these
mAbs is not fully elucidated but current insight is that their effect resides in
the periphery; a contribution of central effect(s) can however not be excluded
at present.
SUMMARY: Although efficacy of all four drugs is modest over placebo in episodic
and chronic migraine prevention and overall comparable with available oral
preventive treatments, current tolerability and (short-term) safety data of this
new treatment approach certainly promise a major step forward for migraine
patients. 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. The neuropeptide calcitonin gene-related peptide is well established as a key
player in the pathogenesis of migraine. Clinical studies show calcitonin
gene-related peptide levels correlate with migraine attacks, and decreases in
this neuropeptide can indicate antimigraine therapy effectiveness. Research has
revealed a wide distribution of expression sites for calcitonin gene-related
peptide in the central and peripheral nervous system. Of these, the calcitonin
gene-related peptide receptor, which binds calcitonin gene-related peptide with
high affinity, has attracted growing interest as a viable target for
antimigraine therapies. An incentive to pursue such research is the continuing
unmet medical need of patients. Triptans have offered some clinical benefit, but
many patients do not respond and these drugs have important safety
considerations. Initial calcitonin gene-related peptide-focused research led to
development of the "gepant" small-molecule calcitonin gene-related peptide
receptor blockers. Positive efficacy reports concerning the gepants have been
tempered by safety findings which led to the discontinuation of some of these
agents. Currently, there is considerable excitement regarding monoclonal
antibodies against calcitonin gene-related peptide (eptinezumab, galcanezumab,
fremanezumab) and the calcitonin gene-related peptide receptor (erenumab). To
date, these monoclonal antibodies have shown promising efficacy in clinical
trials, with no major safety concerns. If ongoing long-term studies show that
their efficacy can be maintained, this may herald a new era for effective
antimigraine therapies. Growth in knowledge about calcitonin gene-related peptide (CGRP) in the
pathophysiology of migraine brought CGRP antagonism to headache medicine.
Failures in development of small molecule CGRP receptor antagonists and
increasing knowledge and use of monoclonal antibodies (mAbs) in medicine led to
the breakthrough development of large molecule anti-CGRP mAbs: eptinezumab,
erenumab, fremanezumab, and galcanezumab. This specifics about CGRP immunology
aims to outline: (1) knowledge needed for CGRP antagonism and (2) developmental
issues of specific CGRP antagonists for provider use. This clinically oriented
review documents IgG structure and function; state of the art of monoclonal IgG
production and ligand-antigen-antibodies in migraine therapeutics contributing
to immunogenic risks and off-target toxicities. Specifics to CGRP ligand,
receptor, antagonism, and molecules, small and large, complete this review.
Completion will facilitate assessment of the similarities, differences, and
application of the forthcoming anti-CGRP receptor and ligand antagonists for
patients. OBJECTIVE: To characterize adult patients with episodic migraine who achieved
100% response to galcanezumab treatment.
BACKGROUND: Galcanezumab is a humanized monoclonal antibody that selectively
binds to the calcitonin gene-related peptide (CGRP) and has demonstrated
efficacy in reducing migraine headache days (MHD) in patients with episodic and
chronic migraine.
METHODS: A post hoc analysis of the proportion of patients with 100% response
(100% reduction from baseline in monthly MHD) was calculated for each month from
pooled data of 2 double-blind, 6-month galcanezumab studies in patients with
episodic migraine (4 to 14 MHD and ≥2 migraine attacks per month at baseline).
The patients were randomized (1:1:2) to monthly subcutaneous galcanezumab,
120 mg (after 240 mg initial loading dose) or 240 mg, or placebo. A generalized
linear mixed model with effects for baseline MHD, treatment, month, and
treatment-by-month interaction was used to estimate the mean monthly response
rate.
RESULTS: The analysis included 1739 patients treated with galcanezumab, 120 mg
(n = 436) or 240 mg (n = 428), or placebo (n = 875). The mean monthly 100%
response rate on an average month in the 6-month double-blind phase was greater
for galcanezumab 120 mg (13.5%) and 240 mg (14.3%) groups vs placebo (5.9%) with
odds ratios of 2.5 (95% confidence interval [CI] 1.9, 3.2) and 2.6 (95% CI 2.0,
3.4), respectively (P < .001). The rate of 100% monthly response increased at
each month over the 6-month double-blind phase with higher rates for
galcanezumab dose groups (9 to 21%) than placebo (2 to 10%) (P < .02).
Evaluation of 100% response by the number of months showed a greater proportion
of galcanezumab-treated patients in either dose group, compared to placebo, were
able to achieve a 100% response (P < .001 up to 3 months); however, though
greater than placebo, few galcanezumab patients had ≥4 months of 100% response
(P < .02). The proportions of patients with 100% response were greatest in the
last 3 months of the treatment. Considering the average number days between
nonconsecutive MHD across the 6-month period (not just during the times of 100%
response), the duration of migraine headache-free periods in the galcanezumab
groups was 29 days for those with at least 1 month of 100% response and 55 days
for those with at least 3 months of 100% response. This gap was approximately 6
to 11 times greater than the mean gap of 5 days observed at baseline.
CONCLUSIONS: More than a third of the patients with episodic migraine treated
with galcanezumab 120 mg or 240 mg achieved 100% response for at least 1 month.
More patients had 100% monthly response in the last 3 months of the 6-month
double-blind period. For those with 100% response for at least 1 month, the
average time between nonconsecutive MHD for the entire treatment period was
nearly 1 month and approached 2 months for patients with 3 or more months of
100% response. BACKGROUND: Patients with high-frequency episodic migraine (HFEM) have a greater
disease burden than those with low-frequency episodic migraine (LFEM). Acute
treatment overuse increases the risk of migraine chronification in patients with
HFEM. Galcanezumab, a humanized monoclonal antibody binding calcitonin
gene-related peptide (CGRP), is effective for migraine prevention with a
favorable safety profile. Here, we investigate whether there are differences in
galcanezumab efficacy in patients with LFEM or with HFEM.
METHODS: Data were pooled from two double-blind, placebo-controlled phase 3
trials; EVOLVE-1 and EVOLVE-2. Patients were 18-65 years old, experienced 4-14
monthly migraine headache days (MHDs) for ≥1 year prior, with onset at
< 50 years of age. Migraine headaches were tracked via electronic
patient-reported outcome system and randomization was stratified by low (LFEM;
4-7 monthly MHDs) or high (HFEM; 8-14 monthly MHDs) frequency. Subgroup analysis
compared the HFEM and LFEM subgroups with a linear or generalized linear mixed
model repeated measures approach.
RESULTS: The intent-to-treat patients (N = 1773) had a mean age of 41.3 years,
were mostly white (75%), female (85%), and 66% of patients had HFEM. In both the
LFEM and HFEM subgroups, the overall (Months 1-6) and monthly changes from
baseline in monthly MHDs and monthly MHDs with acute medication use compared
with placebo were statistically significantly reduced for galcanezumab 120-mg
and 240-mg. Galcanezumab (120-mg and 240-mg) significantly decreased the overall
and monthly MHDs with nausea and/or vomiting, and with photophobia and
phonophobia versus placebo in patients with LFEM or HFEM. In both subgroups, the
mean overall (Months 1-6) and monthly percentages of patients with ≥50%, ≥75%,
and 100% reduction in monthly MHDs from baseline were statistically
significantly greater in patients receiving either dose of galcanezumab versus
placebo. Galcanezumab (120-mg and 240-mg) significantly improved the
Migraine-Specific Quality of Life Questionnaire role function-restrictive domain
score as well as the Migraine Disability Assessment total score versus placebo
for patients with LFEM or HFEM. There were no significant subgroup-by-treatment
interactions.
CONCLUSIONS: Galcanezumab was as effective in patients with HFEM as in those
with LFEM. Associated symptoms, quality of life, and disability were similarly
improved in patients with HFEM or LFEM.
TRIAL REGISTRATION: NCT02614183 , NCT02614196 . Galcanezumab is a humanized immunoglobulin G (IgG) monoclonal antibody (mAb)
indicated for the prevention of migraine that binds to calcitonin gene-related
peptide. A population pharmacokinetic (PK) analysis was performed to
characterize galcanezumab PK using data pooled from 7 clinical studies. Clinical
studies included healthy individuals and patients with episodic or chronic
migraine who were administered between 5 and 300 mg galcanezumab. The PK data
were analyzed using nonlinear mixed-effects modeling. Galcanezumab
concentration-time data were described with a 1-compartment model with
first-order absorption following subcutaneous administration and linear
elimination. At the median body weight of 74 kg, the estimated population
apparent clearance (CL/F) was 0.00785 L/h (34% IIV), the apparent volume of
distribution was 7.33 L (34% IIV), and half-life was 27 days. Patient body
weight was found to have a modest effect of CL/F, with median galcanezumab
concentrations being lower in the heaviest patients compared to the lightest
patients, but this outcome was determined not to be clinically relevant in the
context of model-estimated random variability. Dosing adjusted for body weight
is not warranted in adults. Age, sex, race/ethnicity, immunogenicity,
renal/hepatic markers, and injection-site location did not affect galcanezumab
PK. In conclusion, galcanezumab exhibits PK parameters typical for an IgG mAb
administered subcutaneously. The population PK model developed in this study
demonstrates that galcanezumab exhibits linear PK that was not influenced in a
clinically relevant manner by the patient factors evaluated. |
Which disease was studied in the CADISS trial? | CADISS was a prospective multicentre randomised-controlled trial in acute (within 7 days of onset) carotid and vertebral artery dissection. | Spontaneous internal carotid artery dissection is not an uncommon cause of
ischaemic stroke in younger patients, but multiple cervical arterial dissections
at presentation are uncommon. Recurrence of dissection in a previously normal
artery is common. In this case report we review the history, clinical findings
and management of a 42-year-old woman who presented with stroke and Horner
syndrome and was found to have spontaneous bilateral internal carotid artery
dissection. She was not anticoagulated due to concerns relating to the size of
her infarct. She was treated with a combination of aspirin and clopidogrel. We
use dual antiplatelets for the management of cervical dissections as a part of
the CADISS trial. The patient made good progress with the multidisciplinary team
and was discharged on day 22 with support from the community stroke team. OBJECTIVE: To present the results of the nonrandomized arm of the Cervical
Artery Dissection in Stroke Study (CADISS-NR) trial, comparing anticoagulation
and antiplatelets for prevention of recurrent stroke after carotid and vertebral
dissection, and perform a meta-analysis of these results with previously
published studies comparing the 2 therapeutic strategies.
METHODS: A total of 88 patients from 22 centers with extracranial carotid and
vertebral dissection were recruited within 1 month of symptom onset. The primary
endpoint was recurrent stroke at 3 months. A systematic review was performed,
and results of published studies included in a meta-analysis with the CADISS-NR
results.
RESULTS: In CADISS-NR, one patient in each group had recurrent ischemic stroke
(antiplatelet 1/59 [1.69% ], anticoagulation 1/28 [3.57%]). At the primary
endpoint of 3 months, 3 (5.08%) antiplatelet patients had recurrent TIA,
compared with none in the anticoagulation group. For meta-analysis, there were
data from 40 nonrandomized studies including 1,636 patients. There was no
significant difference between the 2 treatments in recurrent stroke risk
(antiplatelet 13/499 [2.6%], anticoagulant 20/1,137 [1.8%], odds ratio [OR]
1.49) or risk of death (antiplatelet 5/499 [1.00%], anticoagulant 9/1,137
[0.80%], OR 1.27).
CONCLUSION: There is no evidence for superiority of anticoagulation or
antiplatelet therapy in prevention of stoke after carotid and vertebral artery
dissection; however, all data are from nonrandomized studies and randomized
studies are required. The nonrandomized CADISS data show a lower rate of
recurrent stroke than reported in some previous studies.
CLINICAL TRIAL REGISTRATION INFORMATION: www.dissection.co.uk, ISRNCTN44555237. OBJECTIVE: To determine the natural history of dissecting aneurysm (DA) and
whether DA is associated with an increased recurrent stroke risk and whether
type of antithrombotic drugs (antiplatelets vs anticoagulants) modifies the
persistence or development of DA.
METHODS: We included 264 patients with extracranial cervical artery dissection
(CAD) from the Cervical Artery Dissection in Stroke Study (CADISS), a
multicenter prospective study that compared antiplatelet with anticoagulation
therapy. Logistic regression was used to estimate age- and sex-adjusted odds
ratios. We conducted a systematic review of published studies assessing the
natural history of DA and stroke risk in patients with non-surgically-treated
extracranial CAD with DA.
RESULTS: In CADISS, DA was present in 24 of 264 patients at baseline. In 36 of
248 patients with follow-up neuroimaging at 3 months, 12 of the 24 baseline DAs
persisted, and 24 new DA had developed. There was no association between
treatment allocation (antiplatelets vs anticoagulants) and whether DA at
baseline persisted at follow-up or whether new DA developed. During 12 months of
follow-up, stroke occurred in 1 of 48 patients with DA and in 7 of 216 patients
without DA (age- and sex-adjusted odds ratio 0.84; 95% confidence interval
0.10-7.31; p = 0.88). Published studies, mainly retrospective, showed a
similarly low risk of stroke and no evidence of an increased stroke rate in
patients with DA.
CONCLUSIONS: The results of CADISS provide evidence suggesting that DAs may have
benign prognosis and therefore medical treatment should be considered. |
What is the human RCA locus size in bps? | The human RCA locus is located on chromosome 1 (CA1) and consists of approximately 750 kb. | CR1 (CD35) and CR2 (CD21) are structurally related integral transmembrane
glycoproteins that function as cellular receptors for human C3b and C3dg,
respectively. The primary sequence of the most common structural allotype of CR1
and that of CR2 have been established, and ligand binding on the molecules has
been mapped. CR1 and CR2 genes are located in close vicinity in the RCA locus of
chromosome 1. CR1 has a wide cellular/tissular distribution and mediates a
variety of biologic functions, including the transport of C3-bearing immune
complexes on erythrocytes, enhancement of phagocytosis, induction of IL-1
secretion and enhancement of B-cell differentiation. Expression of CR2 is
restricted to B lymphocytes and follicular dendritic cells. The receptor
modulates B-cell growth. CR2 also serves as the receptor for EBV and determines
the cellular tropism of the virus. This review discusses the molecular biology
and functional characteristics of CR1 and CR2. It focuses on alterations of
expression of the receptors in disease, with particular emphasis on the genetic
and acquired factors that contribute to the defective expression of CR1 in
patients with systemic lupus erythematosus. Using an interspecific cross, gene linkage relationships among members of the
murine complement receptor-related genes, C4bp, Cfh, Mcry, and Mcr2, were
analyzed by segregation of RFLP in 200 mice. The human homologues of these genes
are tightly linked, composing the RCA locus, which maps to human chromosome
(Chr.)1q32, within a large linkage group conserved between human Chr.1q21-32 and
mouse Chr.1. RFLP associated with C4bp and Cfh map within this conserved linkage
group; Cfh is located 9 cM telomeric to C4bp, which is consistent with linkage
data for their human homologues. Mcry and Mcr2, while tightly linked, are
located outside the conserved group, 40 cM telomeric to C4bp. These data suggest
that a translocation or inversion occurred within the RCA family during the
evolution of the mouse, defining a breakpoint of this large conserved linkage
group. Genome and expressed sequence tag information of Xenopus tropicalis suggested
that short-consensus repeat (SCR)-containing proteins are encoded by three genes
that are mapped within a 300-kb downstream of PFKFB2, which is a marker gene for
the regulator of complement activation (RCA) loci in human and chicken. Based on
this observation, we cloned the three cDNAs of these proteins using 3'- or
5'-RACE technique. Since their primary structures and locations of the proximity
to the PFKFB2 locus, we named them amphibian RCA protein (ARC) 1, 2, and 3.
Expression in human HEK293 or CHO cells suggested that ARC1 is a soluble protein
of Mr approximately 67 kDa, ARC2 is a membrane protein with Mr 44 kDa, and ARC3
a secretary protein with a putative transmembrane region. They were
N-glycosylated during maturation. In human and chicken RCA clusters, the order
in which genes for soluble, GPI-anchored, and membrane forms of SCR proteins are
arranged is from the distant to proximity to the PFKFB2 gene. However, the
amphibian ARC1, 2, and 3 resembled one another and did not reflect the same
order found in human and chicken RCA genes. This may be due to self-duplication
of ARCs to form a family, and it evolved after the amphibia separated from the
ancestor of the amniotes, which possessed soluble, GPI-anchored, and membrane
forms of SCR protein members. Taken together, frog possesses a RCA locus, but
the constitution of the ARC proteins differs from that of the amniotes with a
unique self-resemblance. |
Is there a role for TET proteins in invariant natural killer T cells (iNKT) cell fate? | Yes. Tet2-TET proteins regulate the lineage specification and TCR-mediated expansion of iNKT cells. TETs are ubiquitously expressed and play diverse roles in gene regulation, imprinting, insulation, intra/interchromosomal interactions, nuclear compartmentalisation, and alternative splicing. Depletion of Tet2 and its ligand, Tet3, from mouse CD4CD8 double-positive thymus-derived cardiomyocytes (iNKT) resulted in dysregulated development and proliferation, with increased expression of tumour suppressor genes and decreased | TET proteins oxidize 5-methylcytosine in DNA to 5-hydroxymethylcytosine and
other oxidation products. We found that simultaneous deletion of Tet2 and Tet3
in mouse CD4+CD8+ double-positive thymocytes resulted in dysregulated
development and proliferation of invariant natural killer T cells (iNKT cells).
Tet2-Tet3 double-knockout (DKO) iNKT cells displayed pronounced skewing toward
the NKT17 lineage, with increased DNA methylation and impaired expression of
genes encoding the key lineage-specifying factors T-bet and ThPOK. Transfer of
purified Tet2-Tet3 DKO iNKT cells into immunocompetent recipient mice resulted
in an uncontrolled expansion that was dependent on the nonclassical major
histocompatibility complex (MHC) protein CD1d, which presents lipid antigens to
iNKT cells. Our data indicate that TET proteins regulate iNKT cell fate by
ensuring their proper development and maturation and by suppressing aberrant
proliferation mediated by the T cell antigen receptor (TCR). |
What is the purpose of the Sunnybrook Facial Grading System? | The Sunnybrook facial grading system is applied to evaluate facial function in patients with facial palsy. | OBJECTIVE: To investigate the extent of within-system reliability and
between-system correlation for the "Sydney" and "Sunnybrook" systems of grading
facial nerve paralysis, and to examine the interobserver reliability and
agreement of the "House Brackmann" grading system.
STUDY DESIGN: A fixed-effects reliability study in which 6 otolaryngologists
viewed videotapes of patients with facial nerve paralysis.
SETTING: University and medical Centers.
PATIENTS: Patients with unilateral lower motor neurone facial nerve dysfunction
greater than 1 year after onset, none of whom had undergone surgical reanimation
procedures. Intervention Twenty-one patients with facial nerve paralysis were
videotaped while they performed a protocol of facial movements. Six
otolaryngologists viewed the videotapes and scored them with the Sydney and
Sunnybrook systems, and then gave a House Brackmann grade.
MAIN OUTCOME MEASURE: The 3 systems of grading facial nerve paralysis were
evaluated and compared with the use of intraclass correlation coefficients,
Pearson's weighted kappa, and percentage exact agreement values.
RESULTS: The Sydney and the Sunnybrook systems had good intrasystem reliability
and high intersystem association for the assessment of voluntary movement.
Grading of synkinesis was found to have low reliability both within and between
systems. The House Brackmann system had substantial reliability as shown by
weighted kappa but had a percentage exact agreement of 44%.
CONCLUSIONS: For clinical grading of voluntary movement, there is good
correlation between ratings given on the Sydney and Sunnybrook systems, and
within each system there is good reliability. The assessment of synkinesis was
far less reliable within, and less related between, systems. Although the
reliability of the House Brackmann system was found to be high, examination of
individual grades revealed some wide variation between trained observers. QUESTION: What is the effect of mime therapy on facial symmetry and severity of
paresis in people with facial nerve paresis?
DESIGN: Randomised controlled trial.
PARTICIPANTS: 50 people recruited from the Outpatient department of two
metropolitan hospitals with facial nerve paresis for more than nine months.
INTERVENTION: The experimental group received three months of mime therapy
consisting of massage, relaxation, inhibition of synkinesis, and co-ordination
and emotional expression exercises. The control group was placed on a waiting
list.
OUTCOME MEASURES: Assessments were made on admission to the trial and three
months later by a measurer blinded to group allocation. Facial symmetry was
measured using the Sunnybrook Facial Grading System. Severity of paresis was
measured using the House-Brackmann Facial Grading System.
RESULTS: After three months of mime therapy, the experimental group had improved
their facial symmetry by 20.4 points (95% CI 10.4 to 30.4) on the Sunnybrook
Facial Grading System compared with the control group. In addition, the
experimental group had reduced the severity of their paresis by 0.6 grade (95%
CI 0.1 to 1.1) on the House-Brackmann Facial Grading System compared with the
control group. These effects were independent of age, sex, and duration of
paresis.
CONCLUSION: Mime therapy improves facial symmetry and reduces the severity of
paresis in people with facial nerve paresis. Although traumatic facial nerve paralysis is a severe handicap, there are no
follow-up studies evaluating outcome after primary repair of traumatic facial
nerve injuries. From May 1988 to August 2005, 27 patients (mean age, 27 years)
were operated for traumatic facial nerve lesions (mean number of affected
branches, 2.2). End-to-end facial nerve repair was always performed. All
patients were invited to our outpatient clinic for standardized questionnaires
(Facial Disability Index, Short Form-36 Health Survey), physical examination
(Sunnybrook Facial Grading System), and clinical photographs. Sixteen patients
participated in the follow-up study (mean, 9.2 years). Mean Facial Disability
Index Physical and Social scores were 86 and 81, respectively, indicating good
subjective facial functioning. The mean Sunnybrook Facial Grading System score
was 74 indicating adequate facial functioning. Mean physical and mental health
scores (Short Form-36 Health Survey) were comparable with normative data.
Primary end-to-end repair of traumatic facial nerve injuries results in good
long-term objective and subjective functional and emotional outcome. The Sunnybrook Facial Grading System (SFGS) is one of the most employed scales
to assess the severity of facial palsy. The aim of our study was to produce an
Italian version of the SFGS and of its explanatory criteria, and to test their
measurement properties when employed by Italian physicians. A multidisciplinary
committee translated and adapted the scale and its criteria into Italian. Six
native Italian physicians, four of whom experienced in facial palsy and two
novices, rated independently 29 videos of facial palsy patients twice. Internal
consistency, agreement and repeatability were evaluated. The Italian version of
the SFGS showed a high degree of internal consistency with a Cronbach's α of
0.91. The test-retest reliability was high for both inter-rater and intra-rater
measures with an ICC of 0.96 and 0.98, respectively. The scores given by the
novice physicians were comparable with the scores given by the expert
physicians. Our study suggests that the Italian version of the SFGS has
excellent internal consistency and reproducibility, comparable to the original
scale. Our study confirms in an independent case record the high measurement
properties of SFGS and provides the first validated Italian scale for the
assessment of facial palsy. BACKGROUND: The Sunnybrook Facial Grading System is considered one of the best
scales available to grade facial motility and postparetic synkinesis. To measure
facial landmarks and movement excursion, a new software, the Facial Assessment
by Computer Evaluation, has been proposed. The aim of this study was to quantify
eye synkinesis improvement after botulinum toxin type A injections using the new
software and to compare this method with the Sunnybrook grading system.
METHODS: The study included 40 injection sessions on 29 Caucasian outpatients
with facial synkinesis. Before and 2 weeks after the injection, patients were
evaluated using the Italian version of the Sunnybrook system. Eyelid fissure
size at rest, during lip puckering, and while smiling was measured with the new
software.
RESULTS: After botulinum infiltration, the Sunnybrook grading system showed a
global facial improvement with reduction of synkinesis and increase of static
and dynamic symmetry. The Facial Assessment software detected an increase of
ocular fissure measure at rest, during lip puckering, and especially during
smiling, and the improvement was positively correlated with initial asymmetry. A
single point of the Sunnybrook system synkinesis score corresponded to a mean
difference of 0.77 mm during smiling and 1.0 mm during lip puckering.
CONCLUSIONS: The Facial Assessment by Computer Evaluation measure allowed the
authors to quantify the improvement of eye synkinesis after botulinum toxin type
A injection. The Sunnybrook Facial Grading System provided an immediate
instrument with which to monitor treatment in routine clinical practice, whereas
the Facial Assessment system gave a more accurate quantitative assessment.
CLINICAL QUESTION/LEVEL OF EVIDENCE: Diagnostic, II. BACKGROUND: After masseteric-facial nerve (V-VII) anastomosis, a new
neurological circuit oversees the facial muscles and patients should learn to
activate the facial movements using the masseteric function.
AIM: To monitor the rehabilitative protocol of facial muscles activation through
teeth clenching and to assess the clinical evolution after V-VII anastomosis in
terms of facial symmetry and functional recovery.
DESIGN: Case series.
SETTING: Outpatients clinic.
POPULATION: Eleven patients undergone V-VII anastomosis for complete unilateral
facial palsy.
METHODS: After surgery, patients underwent a needle electromyography (EMG) and a
rehabilitative training with mirror feedback to learn how to reach the symmetry
at rest and during facial movements through teeth clenching. The rehabilitative
protocol at the first clinical evaluation has been monitored through the Italian
version of Sunnybrook Facial Grading System (SFGS) and the Software Facial
Assessment by Computer Evaluation (FACE). Functional limitations and quality of
life have been evaluated using the Italian version of Facial Disability Index
(FDI). The clinical evolution at 18 months was evaluated with EMG, SFGS, biting
evaluation and FDI.
RESULTS: At the first clinical evaluation after reinnervation, through teeth
clenching patients displayed an improvement of symmetry at rest, symmetry of
voluntary movement, symmetry of smile and composite score of SFGS. Objective
measurement of facial structures with FACE system demonstrated an improvement of
symmetry at rest and during smile through teeth clenching. At 18 months patients
displayed a good reinnervation with a further improvement of SFGS scores and
reduction of functional disability. No biting deficit has been observed.
CONCLUSIONS: After V-VII anastomosis, at the first rehabilitative visit,
patients learn to activate the reinnervated facial muscles through teeth
clenching. Eighteen months after the anastomosis, patients display a further
improvement of voluntary control on facial symmetry and smile and a reduction of
disability.
CLINICAL REHABILITATION IMPACT: Our study illustrates the rehabilitative
protocol after V-VII anastomosis and analyzes the clinical evolution after this
intervention in terms of recovery of facial symmetry and reduction of
disability. This will be instrumental to standardize the rehabilitative protocol
among different centers and to choose the best patient-tailored surgical
approach for subjects affected by complete facial palsy. Background: The Sunnybrook facial grading system (SFGS) is frequently applied to
evaluate facial function in patients with facial palsy, but still now there is
no validated German version of this evaluation sheet. Methods: The original
English version of the SFGS was translated and validated in accordance with
international standards. The interrater reliability from 5 raters (speech
therapy students) and the intrarater reliability from repeated ratings at 2 time
points using video tapes of 18 patients with different types of facial palsy
were analyzed by calculating the intraclass correlation coefficient (ICC) and
other reliability measures. Results: ICC for the interrater reliability for the
4 components of the SFGS, resting symmetry, symmetry during voluntary movements,
synkinesis, and the composite score were ICC 0.845; 0.903; 0.731 and 0.918,
respectively, for the first evaluation and ICC 0.881; 0.932; 0.818 and 0.940,
respectively, for the second evaluation. The mean intrarater reliability for the
4 SFGS scores was ICC=0.791; 0.906; 0.770 and 0.905. Discussion: There is now a
valid German version of the SFGS available that can be used even by novices. The
German version is suitable for evaluation of facial palsies in clinical routine
and studies to allow a better comparability of German patients with results of
the international literature. OBJECTIVES: The aim of the present study was to examine the effect of acquired
unilateral peripheral facial palsy on speech, communication and oral functions
and to study the relationship between the degree of facial palsy and
articulation, saliva control, eating ability and lip force.
MATERIALS AND METHODS: In this descriptive study, 27 patients (15 men and 12
women, mean age 48years) with unilateral peripheral facial palsy were included
if they were graded under 70 on the Sunnybrook Facial Grading System. The
assessment was carried out in connection with customary visits to the ENT Clinic
and comprised lip force, articulation and intelligibility, together with
perceived ability to communicate and ability to eat and control saliva conducted
through self-response questionnaires.
RESULTS: The patients with unilateral facial palsy had significantly lower lip
force, poorer articulation and ability to eat and control saliva compared with
reference data in healthy populations. The degree of facial palsy correlated
significantly with lip force but not with articulation, intelligibility,
perceived communication ability or reported ability to eat and control saliva.
CONCLUSION: Acquired peripheral facial palsy may affect communication and the
ability to eat and control saliva. Physicians should be aware that there is no
direct correlation between the degree of facial palsy and the possible effect on
communication, eating ability and saliva control. Physicians are therefore
recommended to ask specific questions relating to problems with these functions
during customary medical visits and offer possible intervention by a
speech-language pathologist or a physiotherapist. OBJECTIVE: To investigate factors affecting the effect of physical
rehabilitation therapy for synkinesis as a sequela to facial nerve palsy.
METHODS: A total of 37 patients with peripheral facial nerve palsy in
Teine-Keijinkai Hospital were enrolled in this study. All patients showed
synkinesis at 6 months after the onset of facial nerve palsy and were instructed
in physical rehabilitation by expert staff from their first visit. The degree of
synkinesis was evaluated at 6, 9 and 12 months after the onset of facial nerve
palsy based on Sunnybrook facial grading system score and asymmetry in eye
opening width. The patients were divided into two groups by age, gender, cause
of palsy, electroneurography (ENoG) value, onset of synkinesis, initial
treatment and timing of the start of physical rehabilitation.
RESULTS: Female patients and younger patients did not show any deterioration in
synkinesis. Patients in the lower ENoG group and the later onset of synkinesis
group showed significant deterioration in synkinesis after the 6th month from
onset of facial palsy.
CONCLUSION: Physical rehabilitation was shown to prevent significant
deterioration in synkinesis in female and younger patients with facial nerve
palsy. Careful follow-up with regard to synkinesis is required in cases in which
the facial nerve damage is thought to be severe. OBJECTIVE: Facial nerve injury, affecting mainly the marginal mandibular branch,
is the most frequent neurologic complication from parotidectomy. To test a
modified Sunnybrook Facial Grading System as a new tool to assess the facial
nerve function following parotidectomy, emphasizing the marginal mandibular
branch.
METHODS: We reviewed the medical records of 73 post-parotidectomy patients (40
female, 18-84 years old, mean age 53.2 years) with facial nerve sparing,
referred to the Department of Physical Therapy. All patients had parotid
neoplasms or advanced skin cancer, and were followed by the principal author
between 2006 and 2014.
RESULTS: The muscles innervated by the marginal mandibular branch were the most
frequently affected (72.6%), particularly in patients undergoing neck dissection
(p = 0.023). The voluntary movement scores obtained with the modified system
were significantly lower compared with the original version (p < 0.001). The
best and worst scores were observed in patients with benign parotid tumors and
skin cancer, respectively. Patients requiring neck dissection (p = 0.031) and
resection of other structures (p = 0.021) had the lowest scores, evidenced only
with the modified version. Patients with maligt tumors had significantly
worse ratings, regardless of the Sunnybrook system version. The
post-physiotherapy analysis involved 50 patients. The worst facial
rehabilitation outcomes were related to the marginal mandibular branch function.
CONCLUSION: The modified Sunnybrook Facial Grading System improved the marginal
mandibular branch assessment, preserving the evaluation of other facial nerve
branches. |
What is the function of the PDZ domain in SATB1? | N-terminal PDZ-like domain of chromatin organizer SATB1 contributes towards its function as transcription regulator. We found this dimerization region to have sequence similarity to PDZ domains, which have been previously shown to be involved in signaling by conferring protein-protein interactions. These studies clearly demonstrated the role of PDZ domain of SATB1 in global gene regulation presumably through its interaction with other cellular proteins. PDZ domain-mediated dimerization and homeodomain-directed specificity are required for high-affinity DNA binding by SATB1. | SATB1 is expressed primarily in thymocytes and orchestrates temporal and spatial
expression of a large number of genes in the T-cell lineage. SATB1 binds to the
bases of chromatin loop domains in vivo, recognizing a special DNA context with
strong base-unpairing propensity. The majority of thymocytes are eliminated by
apoptosis due to selection processes in the thymus. We investigated the fate of
SATB1 during thymocyte and T-cell apoptosis. Here we show that SATB1 is
specifically cleaved by a caspase 6-like protease at amino acid position 254 to
produce a 65-kDa major fragment containing both a base-unpairing region
(BUR)-binding domain and a homeodomain. We found that this cleavage separates
the DNA-binding domains from amino acids 90 to 204, a region which we show to be
a dimerization domain. The resulting SATB1 monomer loses its BUR-binding
activity, despite containing both its DNA-binding domains, and rapidly
dissociates from chromatin in vivo. We found this dimerization region to have
sequence similarity to PDZ domains, which have been previously shown to be
involved in signaling by conferring protein-protein interactions. SATB1 cleavage
during Jurkat T-cell apoptosis induced by an anti-Fas antibody occurs
concomitantly with the high-molecular-weight fragmentation of chromatin of
~50-kb fragments. Our results suggest that mechanisms of nuclear degradation
early in apoptotic T cells involve efficient removal of SATB1 by disrupting its
dimerization and cleavage of genomic DNA into loop domains to ensure rapid and
efficient disassembly of higher-order chromatin structure. The special AT-rich DNA-binding protein 1 (SATB1) is a matrix attachment region
(MAR)-binding protein that acts as a global repressor via recruitment of
CtBP1:HDAC1-containing co-repressors to its binding targets. The N-terminal
PSD95/Dlg-A/ZO-1 (PDZ)-like domain of SATB1 mediates interactions with several
chromatin proteins. In the present study, we set out to address whether the
PDZ-domain-mediated interactions of SATB1 are critical for its in vivo function
as a global repressor. We reasoned that since the N-terminal PDZ-like domain
(amino acid residues 1-204) lacks DNA binding activity, it would fail to recruit
the interacting partners of SATB1 to its genomic binding sites and hence would
not repress the SATB1-regulated genes. Indeed, in vivo MAR-linked luciferase
reporter assay revealed that overexpression of the PDZ-like domain resulted in
de-repression, indicating that the PDZ-like domain exerts a domit negative
effect on genes regulated by SATB1. Next, we developed a stable domit
negative model in human embryonic kidney (HEK) 293T cells that conditionally
expressed the N-terminal 1-204 region harbouring the PDZ-like domain of SATB1.
To monitor the effect of sequestration of the interaction partners on the global
gene regulation by SATB1, transcripts from the induced and uninduced clones were
subjected to gene expression profiling. Clustering of expression data revealed
that 600 out of 19000 genes analysed were significantly upregulated upon
overexpression of the PDZ-like domain. Induced genes were found to be involved
in important signalling cascades and cellular functions. These studies clearly
demonstrated the role of PDZ domain of SATB1 in global gene regulation
presumably through its interaction with other cellular proteins. |
What cellular process is the protein clathrin involved in? | Clathrin is a central regulator of endocytosis in all eukaryotes that plays a role in bacterial and plastid differentiation | Receptor-mediated endocytosis proceeds by transfer of receptor-ligand complexes
from clathrin-coated pits at the cell surface to uncoated endocytic vesicles
termed receptosomes (or endosomes). These vesicles have now been purified more
than 37-fold based on their content of newly internalized epidermal growth
factor. 125I-labeled EGF was bound to human KB carcinoma cells at 4 degrees C,
and then the cells were warmed to 37 degrees C for 8 min and disrupted. The
purification scheme involved density gradient centrifugation on colloidal silica
and sucrose and gel filtration on Sephacryl S-1000. Relative to homogenate,
receptosomes are enriched 4.3-fold in their cholesterol content and depleted in
enzyme markers for plasma membranes (2- to 3-fold) and lysosomes (9-fold).
Receptosomes have a polypeptide composition that is different from plasma
membrane, lysosome, and other homogenate fractions. They are enriched in
transferrin receptors (30-fold) and in unidentified Mr 70,000-75,000
glycoprotein(s); they contain phosphomannosyl receptors. They do not contain
detectable amounts of clathrin. When many ligands bind to cell-surface receptors, ligand-receptor complexes are
internalized via clathrin coated pits by a process called receptor-mediated
endocytosis. The cytoplasmic fate of ligands internalized within endocytic
vesicles or endosomes is variable. For example, maternal immunoglobulins are
transported through the cytoplasm of neonatal intestinal epithelial cells and
are exocytosed at the basolateral surface. However, other ligands are degraded
as a result of their delivery to the lysosomal compartment of cells. Although
the translocation of endosomes to the Golgi region in the cell centre seems to
be a general phenomenon presumably coupled to ligand degradation by lysosomes
and endosomes and lysosomes undergo saltatory movements within the cytoplasm,
the spatial control of interaction between the two structures is not understood.
To address this problem we have begun to examine the spatial and temporal
intracellular distribution of endosomes and lysosomes. Utilizing a new
fluorescent microscopic approach, we have now been able simultaneously to
visualize endosome and lysosome populations in living cells. Our results suggest
that a specific relocation of lysosomes is rapidly induced upon binding of
different types of ligands to the cell surface; this migration of lysosomes to
the Golgi region of the cell precedes the translocation of endosomes into the
same area. Clathrin is involved in the endocytosis and exocytosis of cellular proteins and
the process of virus infection. We have previously demonstrated that large
hepatitis delta antigen (HDAg-L) functions as a clathrin adaptor, but the
detailed mechanisms of clathrin involvement in the morphogenesis of hepatitis
delta virus (HDV) are not clear. In this study, we found that clathrin heavy
chain (CHC) is a key determit in the morphogenesis of HDV. HDAg-L with a
single amino acid substitution at the clathrin box retained nuclear export
activity but failed to interact with CHC and to assemble into virus-like
particles. Downregulation of CHC function by a domit-negative mutant or by
short hairpin RNA reduced the efficiency of HDV assembly, but not the secretion
of hepatitis B virus subviral particles. In addition, the coexistence of a
cell-permeable peptide derived from the C terminus of HDAg-L significantly
interfered with the intracellular transport of HDAg-L. HDAg-L, small HBsAg, and
CHC were found to colocalize with the trans-Golgi network and were highly
enriched on clathrin-coated vesicles. Furthermore, genotype II HDV, which
assembles less efficiently than genotype I HDV does, has a putative clathrin box
in its HDAg-L but interacted only weakly with CHC. The assembly efficiency of
the various HDV genotypes correlates well with the CHC-binding activity of their
HDAg-Ls and coincides with the severity of disease outcome. Thus, the clathrin
box and the nuclear export signal at the C terminus of HDAg-L are potential new
molecular targets for HDV therapy. Endocytosis is an essential cellular process in eukaryotic cells that involves
concordant functions of clathrin and adaptor proteins, various protein and lipid
kinases, phosphatases and the actin cytoskeleton. In Saccharomyces cerevisiae,
Ark1p is a member of the serine/threonine protein kinase (SPK) family that
affects profoundly the organization of the cortical actin cytoskeleton. To study
the function of MoArk1, an Ark1p homologue identified in Magnaporthe oryzae, we
disrupted the MoARK1 gene and characterized the ΔMoark1 mutant strain. The
ΔMoark1 mutant exhibited various defects ranging from mycelial growth and
conidial formation to appressorium-mediated host infection. The ΔMoark1 mutant
also exhibited decreased appressorium turgor pressure and attenuated virulence
on rice and barley. In addition, the ΔMoark1 mutant displayed defects in
endocytosis and formation of the Spitzenkörper, and was hyposensitive to
exogenous oxidative stress. Moreover, a MoArk1-green fluorescent protein
(MoArk1-GFP) fusion protein showed an actin-like localization pattern by
localizing to the apical regions of hyphae. This pattern of localization
appeared to be regulated by the N-ethylmaleimide-sensitive factor attachment
protein receptor (SNARE) proteins MoSec22 and MoVam7. Finally, detailed analysis
revealed that the proline-rich region within the MoArk1 serine/threonine kinase
(S_TKc) domain was critical for endocytosis, subcellular localization and
pathogenicity. These results collectively suggest that MoArk1 exhibits conserved
functions in endocytosis and actin cytoskeleton organization, which may underlie
growth, cell wall integrity and virulence of the fungus. Endocytosis mediated by clathrin, a cellular process by which cells internalize
membrane receptors and their extracellular ligands, is an important component of
cell signaling regulation. Actin polymerization is involved in endocytosis in
varying degrees depending on the cellular context. In yeast, clathrin-mediated
endocytosis requires a pulse of polymerized actin and its regulators, which
recruit and activate the Arp2/3 complex. In this article, we seek to identify
the main protein-protein interactions that 1) cause actin and its regulators to
appear in pulses, and 2) determine the effects of key mutations and drug
treatments on actin and regulator assembly. We perform a joint
modeling/experimental study of actin and regulator dynamics during endocytosis
in the budding yeast Saccharomyces cerevisiae. We treat both a stochastic model
that grows an explicit three-dimensional actin network, and a simpler
two-variable Fitzhugh-Nagumo type model. The models include a negative-feedback
interaction of F-actin onto the Arp2/3 regulators. Both models explain the pulse
time courses and the effects of interventions on actin polymerization: the
surprising increase in the peak F-actin count caused by reduced regulator
branching activity, the increase in F-actin resulting from slowing of actin
disassembly, and the increased Arp2/3 regulator lifetime resulting from
latrunculin treatment. In addition, they predict that decreases in the regulator
branching activity lead to increases in accumulation of regulators, and we
confirmed this prediction with experiments on yeast harboring mutations in the
Arp2/3 regulators, using quantitative fluorescence microscopy. Our experimental
measurements suggest that the regulators act quasi-independently, in the sense
that accumulation of a particular regulator is most strongly affected by
mutations of that regulator, as opposed to the others. Endocytosis is a crucial cellular process in eukaryotic cells which involves
clathrin and/or adaptor proteins, lipid kinases, phosphatases and the actin
cytoskeleton. Verprolin proteins, such as Vrp1 in Saccharomyces cerevisiae, are
conserved family proteins that regulate actin binding and endocytosis. Here, we
identified and characterized MoVrp1 as the yeast Vrp1 homolog in Magnaporthe
oryzae. Deletion of the MoVRP1 gene resulted in defects in vegetative growth,
asexual development, and infection of the host plant. The ∆Movrp1 mutants also
exhibited decreased extracellular peroxidase and laccase activities and showed
defects in colony pigmentation, hyphal surface hydrophobicity, cell wall
integrity, autophagy, endocytosis, and secretion of avirulent effector. Our
studies provided new evidences that MoVrp1 involved in actin cytoskeleton is
important for growth, morphogenesis, cellular trafficking, and fungal
pathogenesis. Author information:
(1)MOE Key Laboratory of Macromolecular Synthesis and Functionalization,
Department of Polymer Science and Engineering, Zhejiang University, Hangzhou
310027, China. Electronic address: [email protected].
(2)MOE Key Laboratory of Macromolecular Synthesis and Functionalization,
Department of Polymer Science and Engineering, Zhejiang University, Hangzhou
310027, China. Electronic address: [email protected].
(3)MOE Key Laboratory of Macromolecular Synthesis and Functionalization,
Department of Polymer Science and Engineering, Zhejiang University, Hangzhou
310027, China. Electronic address: [email protected].
(4)MOE Key Laboratory of Macromolecular Synthesis and Functionalization,
Department of Polymer Science and Engineering, Zhejiang University, Hangzhou
310027, China. Electronic address: [email protected].
(5)MOE Key Laboratory of Macromolecular Synthesis and Functionalization,
Department of Polymer Science and Engineering, Zhejiang University, Hangzhou
310027, China. Electronic address: [email protected].
(6)MOE Key Laboratory of Macromolecular Synthesis and Functionalization,
Department of Polymer Science and Engineering, Zhejiang University, Hangzhou
310027, China. Electronic address: [email protected]. Clathrin-mediated endocytosis (CME) is a cellular trafficking process in which
cargoes and lipids are internalized from the plasma membrane into vesicles
coated with clathrin and adaptor proteins. CME is essential for many
developmental and physiological processes in plants, but its underlying
mechanism is not well characterized compared with that in yeast and animal
systems. Here, we searched for new factors involved in CME in Arabidopsis
thaliana by performing tandem affinity purification of proteins that interact
with clathrin light chain, a principal component of the clathrin coat. Among the
confirmed interactors, we found two putative homologs of the clathrin-coat
uncoating factor auxilin previously described in non-plant systems.
Overexpression of AUXILIN-LIKE1 and AUXILIN-LIKE2 in Arabidopsis caused an
arrest of seedling growth and development. This was concomitant with inhibited
endocytosis due to blocking of clathrin recruitment after the initial step of
adaptor protein binding to the plasma membrane. By contrast, auxilin-like1/2
loss-of-function lines did not present endocytosis-related developmental or
cellular phenotypes under normal growth conditions. This work contributes to the
ongoing characterization of the endocytotic machinery in plants and provides a
robust tool for conditionally and specifically interfering with CME in
Arabidopsis. |
Thymoquinone is ineffective against radiation induced enteritis, yes or no? | No, Thymoquinone has been found to be effective against radiation induced enteritis | Radiation enteritis is an old but emerging question induced by the application
of radiation. However, no effective drugs for radiation enteritis in clinic. In
this study, we found that thymoquinone (TQ) could mitigate intestinal damages
induced by irradiation. After exposure to irradiation, TQ-treated improved the
irradiated mice survival rate, ameliorated intestinal injury and increased the
numbers of intestinal crypts. Furthermore, Lgr5+ ISCs and their daughter cells,
including Vil1+ enterocytes, Ki67+ cells and lysozyme+ Paneth cells, were all
significantly increased with TQ treatment. In addition, P53, γH2AX, caspase8,
caspase9 and caspase3 expression were all reduced by TQ. Our data showed that TQ
modulated DNA damages and decreased the apoptosis in the small intestine. TQ
might be used for radiation enteritis treatment. |
Which are the databases for intrinsic protein disorders? | Intrinsic disorder (ID), i.e. the lack of a unique folded conformation at physiological conditions, is a common feature for many proteins, which requires specialized biochemical experiments that are not high-throughput. DisProt and MobiDB are databases for intrinsic protein disorders. | BACKGROUND: Intrinsic protein disorder is becoming an increasingly important
topic in protein science. During the last few years, intrinsically disordered
proteins (IDPs) have been shown to play a role in many important biological
processes, e.g. protein signalling and regulation. This has sparked a need to
better understand and characterize different types of IDPs, their functions and
roles. Our recently published database, MobiDB, provides a centralized resource
for accessing and analysing intrinsic protein disorder annotations.
RESULTS: Here, we present a thorough description and analysis of the data made
available by MobiDB, providing descriptive statistics on the various available
annotation sources. Version 1.2.1 of the database contains annotations for ca.
4,500,000 UniProt sequences, covering all eukaryotic proteomes. In addition, we
describe a novel consensus annotation calculation and its related weighting
scheme. The comparison between disorder information sources highlights how the
MobiDB consensus captures the main features of intrinsic disorder and correlates
well with manually curated datasets. Finally, we demonstrate the annotation of
13 eukaryotic model organisms through MobiDB's datasets, and of an example
protein through the interactive user interface.
CONCLUSIONS: MobiDB is a central resource for intrinsic disorder research,
containing both experimental data and predictions. In the future it will be
expanded to include additional information for all known proteins. MOTIVATION: Intrinsic disorder (ID), i.e. the lack of a unique folded
conformation at physiological conditions, is a common feature for many proteins,
which requires specialized biochemical experiments that are not high-throughput.
Missing X-ray residues from the PDB have been widely used as a proxy for ID when
developing computational methods. This may lead to a systematic bias, where
predictors deviate from biologically relevant ID. Large benchmarking sets on
experimentally validated ID are scarce. Recently, the DisProt database has been
renewed and expanded to include manually curated ID annotations for several
hundred new proteins. This provides a large benchmark set which has not yet been
used for training ID predictors.
RESULTS: Here, we describe the first systematic benchmarking of ID predictors on
the new DisProt dataset. In contrast to previous assessments based on missing
X-ray data, this dataset contains mostly long ID regions and a significant
amount of fully ID proteins. The benchmarking shows that ID predictors work
quite well on the new dataset, especially for long ID segments. However, a large
fraction of ID still goes virtually undetected and the ranking of methods is
different than for PDB data. In particular, many predictors appear to confound
ID and regions outside X-ray structures. This suggests that the ID prediction
methods capture different flavors of disorder and can benefit from highly
accurate curated examples.
AVAILABILITY AND IMPLEMENTATION: The raw data used for the evaluation are
available from URL: http://www.disprot.org/assessment/.
CONTACT: [email protected].
SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics
online. Author information:
(1)Department of Biomedical Sciences, University of Padua, via U. Bassi 58/b,
35131 Padua, Italy.
(2)Institute of Biosciences and Medical Technology, Arvo Ylpön katu 34, 33520
Tampere, Finland.
(3)Department of Agricultural Sciences, University of Udine, via Palladio 8,
33100 Udine, Italy.
(4)Fondazione Edmund Mach, Via E. Mach 1, 38010 S. Michele all'Adige, Italy.
(5)Department of Biosciences, University of Milan, 20133 Milano, Italy.
(6)Conway Institute of Biomolecular & Biomedical Research, University College
Dublin, Belfield, Dublin 4, Ireland.
(7)UCD School of Medicine & Medical Science, University College Dublin,
Belfield, Dublin 4, Ireland.
(8)MTA-ELTE Lendület Bioinformatics Research Group, Department of Biochemistry,
Eötvös Loránd University, 1/c Pázmány Péter sétány, H-1117, Budapest, Hungary.
(9)Institute of Enzymology, Research Centre for Natural Sciences, Hungarian
Academy of Sciences, PO Box 7, H-1518 Budapest, Hungary.
(10)Structural Bioinformatics Group, Department of Science and Technology,
National University of Quilmes, CONICET, Roque Saenz Pena 182, Bernal B1876BXD,
Argentina.
(11)Department of Chemistry, University of Cambridge, Cambridge CB2 1EW, UK.
(12)Structural Biology Brussels, Vrije Universiteit Brussel (VUB), Brussels
1050, Belgium.
(13)VIB-VUB Center for Structural Biology, Flanders Institute for Biotechnology
(VIB), Brussels 1050, Belgium.
(14)Interuniversity Institute of Bioinformatics in Brussels, ULB/VUB, 1050
Brussels, Belgium.
(15)CNR Institute of Neuroscience, via U. Bassi 58/b, 35131 Padua, Italy. |
List the 5 different human immunoglobulin heavy chains. | The 5 human immunoglobulin heavy chains are Alpha, Delta Epsilon, Gamma and Mu | In mature B cells of mice and most mammals, cellular release of single H chain
Abs without L chains is prevented by H chain association with Ig-specific
chaperons in the endoplasmic reticulum. In precursor B cells, however, surface
expression of mu-H chain in the absence of surrogate and conventional L chain
has been identified. Despite this, Ag-specific single H chain Ig repertoires,
using mu-, gamma-, epsilon-, or alpha-H chains found in conventional Abs, are
not produced. Moreover, removal of H chain or, separately, L chain
(kappa/lambda) locus core sequences by gene targeting has prevented B cell
development. In contrast, H chain-only Abs are produced abundantly in Camelidae
as H2 IgG without the C(H)1 domain. To test whether H chain Abs can be produced
in mice, and to investigate how their expression affects B cell development, we
introduced a rearranged dromedary gamma2a H chain into the mouse germline. The
dromedary transgene was expressed as a naturally occurring Ag-specific
disulphide-linked homodimer, which showed that B cell development can be
instigated by expression of single H chains without L chains. Lymphocyte
development and B cell proliferation was accomplished despite the absence of L
chain from the BCR complex. Endogenous Ig could not be detected, although V(D)J
recombination and IgH/L transcription was unaltered. Furthermore, crossing the
dromedary H chain mice with mice devoid of all C genes demonstrated without a
doubt that a H chain-only Ab can facilitate B cell development independent of
endogenous Ig expression, such as mu- or delta-H chain, at early developmental
stages. The neoplastic proliferation of single clones of plasma cells causes synthesis
of very large amount of monoclonal immunoglobulins consisting of only one type
of heavy either the gamma, alpha, mu, delta or epsilon chain or only kappa or
lambda light chains. Each monoclonal immunolobulin differs idiotypically from
each other. These monoclonal immunoglobulins are also called paraproteins and
are frequently associated with a broad heterogeneous group of plasma cell
dyscrasias. Occasionally their presence is observed in a few benign conditions
and in old age. In the present review a detailed account of different types of
monoclonal gammapathies are described. In the present study, monoclonal gammapathy was identified in a total of 245
patients of plasma cell dyscrasias during period of 1987 to 2000. The monoclonal
band was identified in serum by agar gel electrophoresis in all the cases and in
urine in a few cases. Characterization of paraprotein (monoclonal immunoglobulin
class and light chain type) was carried out by employing immunoelectrophoresis
and/or immunofixation electrophoresis using heavy chain specific gamma, alpha,
mu, delta and epsilon and light chain specific kappa (K), lambda (λ) antisera.
Serum immunoglobulins Ig G, Ig A, and Ig M were estimated by immunoturbidometry.
Serum urea, creatinine, uric acid, alkaline phosphatase, total proteins,
albumin, calcium and phosphorus were estimated by using routine biochemical
methods. Among the 245 cases, 73.1% monoclonal gammapathies were of secretory
type and 7.3% were non-secretory. Monoclonal gammapathies were associated with
80.4% of multiple myeloma, 8.9% of solitary plasmacytoma, 4.1% of
extra-medullary plasmacytoma, 3.3% of lymphoma and 2.9% of plasma cell leukemia.
Classification of secretory monoclonal immunoglobulin revealed monoclonal
immunoglobulin Ig G in 74%, Ig A 15% and Ig M in 2.9% cases. |
Has the Spanich flu virus been reconstructed? | Tes,
Reconstruction of the 1918 influenza virus has facilitated considerable advancements in our understanding of this extraordinary pandemic virus. | The influenza pandemic of 1918-1919 killed approximately 50 million people. The
unusually severe morbidity and mortality associated with the pandemic spurred
physicians and scientists to isolate the etiologic agent, but the virus was not
isolated in 1918. In 1996, it became possible to recover and sequence highly
degraded fragments of influenza viral RNA retained in preserved tissues from
several 1918 victims. These viral RNA sequences eventually permitted
reconstruction of the complete 1918 virus, which has yielded, almost a century
after the deaths of its victims, novel insights into influenza virus biology and
pathogenesis and has provided important information about how to prevent and
control future pandemics. |
What is the basis of the BLISS technique? | Here we present Breaks Labeling In Situ and Sequencing (BLISS), a versatile and quantitative method for genome-wide profiling of DNA double-strand breaks. | Precisely measuring the location and frequency of DNA double-strand breaks
(DSBs) along the genome is instrumental to understanding genomic fragility, but
current methods are limited in versatility, sensitivity or practicality. Here we
present Breaks Labeling In Situ and Sequencing (BLISS), featuring the following:
(1) direct labelling of DSBs in fixed cells or tissue sections on a solid
surface; (2) low-input requirement by linear amplification of tagged DSBs by in
vitro transcription; (3) quantification of DSBs through unique molecular
identifiers; and (4) easy scalability and multiplexing. We apply BLISS to
profile endogenous and exogenous DSBs in low-input samples of cancer cells,
embryonic stem cells and liver tissue. We demonstrate the sensitivity of BLISS
by assessing the genome-wide off-target activity of two CRISPR-associated
RNA-guided endonucleases, Cas9 and Cpf1, observing that Cpf1 has higher
specificity than Cas9. Our results establish BLISS as a versatile, sensitive and
efficient method for genome-wide DSB mapping in many applications. DNA double-strand breaks (DSBs) are major DNA lesions that are constantly formed
during physiological processes such as DNA replication, transcription, and
recombination, or as a result of exogenous agents such as ionizing radiation,
radiomimetic drugs, and genome editing nucleases. Unrepaired DSBs threaten
genomic stability by leading to the formation of potentially oncogenic
rearrangements such as translocations. In past few years, several methods based
on next-generation sequencing (NGS) have been developed to study the genome-wide
distribution of DSBs or their conversion to translocation events. We developed
Breaks Labeling, Enrichment on Streptavidin, and Sequencing (BLESS), which was
the first method for direct labeling of DSBs in situ followed by their
genome-wide mapping at nucleotide resolution (Crosetto et al., Nat Methods
10:361-365, 2013). Recently, we have further expanded the quantitative nature,
applicability, and scalability of BLESS by developing Breaks Labeling In Situ
and Sequencing (BLISS) (Yan et al., Nat Commun 8:15058, 2017). Here, we first
present an overview of existing methods for genome-wide localization of DSBs,
and then focus on the BLESS and BLISS methods, discussing different assay design
options depending on the sample type and application. Lignin is one of the most prevalent biopolymers on the planet and a major
component of lignocellulosic biomass. This phenolic polymer plays a vital
structural and protective role in the development and life of higher plants.
Although the intricate mechanisms regulating lignification processes in vivo
strongly impact the industrial valorization of many plant-derived products, the
scientific community still has a long way to go to decipher them. In a simple
three-step workflow, the dual labeling protocol presented herein enables
bioimaging studies of actively lignifying zones of plant tissues. The first step
consists in the metabolic incorporation of two independent chemical reporters,
surrogates of the two native monolignols that give rise to lignin H- and
G-units. After incorporation into growing lignin polymers, each reporter is then
specifically labeled with its own fluorescent probe via a sequential combination
of bioorthogonal SPAAC/CuAAC click reactions. Combined with lignin
autofluorescence, this approach leads to the generation of three-color
localization maps of lignin within plant cell walls by confocal fluorescence
microscopy and provides precise spatial information on the presence or absence
of active lignification machinery at the scale of plant tissues, cells and
different cell wall layers. |
List 3 NK3R antagonists. | NK3 receptor antagonists include MLE4901 (also known as AZD4901), SB222200 and ESN364. | CONTEXT: Women's health disorders are commonly treated by agents that suppress
the hypothalamic-pituitary-gonadal axis. NK3 receptor antagonism modulates this
axis with distinct pharmacology compared to existing therapies.
OBJECTIVE: The study aim was to evaluate safety, pharmacokinetics, and
pharmacodynamics on gonadotropins and sex hormones after single- and
multiple-dose administration of an NK3R antagonist to healthy men and women.
DESIGN AND SETTING: This was a first-in-human, double-blind, placebo-controlled,
combined single and multiple ascending dose trial.
PARTICIPANTS: Forty-one men and 24 regularly cycling women participated in the
study.
INTERVENTION(S): In part 1 of the study, men received single oral doses of 3-180
mg or placebo. In part 2, men received placebo or 20, 60, or 180 mg each day for
10 days. In part 3, women received placebo or 20, 60, or 180 mg each day for 21
days, where dosing was initiated on day 3 ± 2 after menses.
MAIN OUTCOME MEASURE(S): Safety, tolerability, pharmacokinetics, and
pharmacodynamics on circulating levels of LH, FSH, testosterone, estradiol, and
progesterone, in addition to physiological biomarkers of endometrial thickening,
follicle growth, and the duration of the menstrual cycle were evaluated.
RESULTS: ESN364 was well-tolerated and rapidly bioavailable with linear
pharmacokinetics and no drug accumulation with repeated, daily oral
administration. Drug treatment dose-dependently decreased basal LH, but not FSH,
and consequently decreased estradiol and progesterone (in women) as well as
testosterone (in men). The hormonal changes in women corresponded to delayed
ovulation, decreased endometrial thickening, impeded follicular maturation, and
prolongation of the menstrual cycle. Drug effects were rapidly reversible.
CONCLUSIONS: Oral administration of the NK3R antagonist, ESN364, suppressed the
hypothalamic-pituitary-gonadal axis in healthy volunteers by selective
modulation of gonadotropin secretion, leading to a restrained decrease in
ovarian hormone levels in women. These results suggest that ESN364 may offer
therapeutic benefit in the treatment of women's health disorders with a
mitigated risk of menopausal-like adverse events. OBJECTIVES: Neurokinin B (NKB) and kisspeptin are obligate for normal
gonadotropin secretion, and links between gonadotropin-releasing hormone (GnRH)
pulsatility and vasomotor symptoms have been proposed. Using a selective NKB
receptor (NK3R) antagonist, the role of NKB in the hypergonadotropic state in
menopausal women was explored.
METHODS: Eleven postmenopausal women were administered the NK3R antagonist
MLE4901 at 40 mg twice daily orally for 7 days. Ten-minute blood sampling for 8
h was performed before and on the last day of NK3R antagonist treatment for
luteinising hormone (LH) pulsatility analysis with kisspeptin-10 (0.3 µg/kg i.v.
bolus) administered at 6 h on both days. Hot flash frequency and severity were
self-reported for 7 days before and during NK3R antagonist administration.
RESULTS: LH fell from 29.3 ± 4.1 to 24.4 ± 3.8 IU/L (p < 0.05) after 7 days of
NK3R antagonist treatment, with no change in follicle-stimulating hormone (FSH).
Basal (non-pulsatile) LH secretion was reduced (549.0 ± 70.8 vs. 366.1 ± 92.1
IU/L/6 h, p = 0.006), and while the LH pulse frequency did not change in the
group as a whole (from 0.8 ± 0.1 to 0.7 ± 0.1 pulses/h, ns), it did fall in the
8 women with hot flashes (from 1.0 ± 0.1 to 0.7 ± 0.1 pulses/h, p < 0.05). These
women also reported a reduction in hot flash frequency (from 3.4 ± 1.2 to 1.0 ±
0.6 hot flashes/day, p = 0.008) whilst taking the NK3R antagonist. Kisspeptin-10
did not affect LH secretion with or without the NK3R antagonist.
CONCLUSIONS: The administration of an NK3R antagonist indicates a role for NKB
in the regulation of LH/GnRH in postmenopausal women, whereas the lack of
response to kisspeptin may reflect the hypo-oestrogenic state. These data
support a link of LH/GnRH pulsatility and vasomotor symptoms with NK3R
antagonism as a potential therapeutic approach. Loss-of-function or inactivating mutations in the genes coding for kisspeptin
and its receptor (KISS1R) or neurokinin B (NKB) and the NKB receptor (NK3R) in
humans result in a delay in or the absence of puberty. However, precise
mechanisms of kisspeptin and NKB signaling in the regulation of the pubertal
increase in gonadotropin-releasing hormone (GnRH) release in primates are
unknown. In this study, we conducted a series of experiments infusing agonists
and antagonists of kisspeptin and NKB into the stalk-median eminence, where
GnRH, kisspeptin, and NKB neuroterminal fibers are concentrated, and measuring
GnRH release in prepubertal and pubertal female rhesus monkeys. Results indicate
that (1) similar to those previously reported for GnRH stimulation by the KISS1R
agonist (i.e., human kisspeptin-10), the NK3R agonist senktide stimulated GnRH
release in a dose-responsive manner in both prepubertal and pubertal monkeys;
(2) the senktide-induced GnRH release was blocked in the presence of the KISS1R
antagonist peptide 234 in pubertal but not prepubertal monkeys; and (3) the
kisspeptin-induced GnRH release was blocked in the presence of the NK3R
antagonist SB222200 in the pubertal but not prepubertal monkeys. These results
are interpreted to mean that although, in prepubertal female monkeys, kisspeptin
and NKB signaling to GnRH release is independent, in pubertal female monkeys, a
reciprocal signaling mechanism between kisspeptin and NKB neurons is
established. We speculate that this cooperative mechanism by the kisspeptin and
NKB network underlies the pubertal increase in GnRH release in female monkeys. |
Is Verubecestat effective for Alzheimer's Disease? | No. Verubecestat did not reduce cognitive or functional decline in patients with mild-to-moderate Alzheimer's disease and was associated with treatment-related adverse events. | The amyloid hypothesis has long been the central dogma in drug discovery for
Alzheimer's disease (AD), leading to many small-molecule and biological drug
candidates. One major target has been the β-site
amyloid-precursor-protein-cleaving enzyme 1 (BACE-1), with many big pharma
companies expending great resources in the search for BACE-1 inhibitors. The
lack of efficacy of verubecestat in mild-to-moderate AD raises important
questions about the timing of intervention with BACE-1 inhibitors, and
anti-amyloid therapies in general, in AD treatment. It also suggests new
possibilities for discovering BACE-1-targeted compounds with more complex
mechanisms of actions and improved efficacy. Herein, we review the major
advances in BACE-1 drug discovery, from single-target small molecule inhibitors
to multitarget compounds. We discuss these compounds as innovative tools for
better understanding the complexity of AD and for identifying efficacious drug
candidates to treat this devastating disease. β-site amyloid precursor protein cleaving enzyme 1 (BACE1) is required for the
production of β-amyloid (Aβ) peptides and is considered a potential treatment
target for Alzheimer's disease (AD). To support Japan's participation in the
global clinical development program, we characterized the safety,
pharmacokinetics (PKs), and pharmacodynamics of the BACE1 inhibitor verubecestat
(MK-8931) in 24 healthy Japanese adults in a two-part, single-center,
randomized, placebo-controlled phase I trial (protocol MK-8931-007) and compared
the results with historical data from non-Japanese subjects. Both single (20,
100, and 450 mg) and multiple (80 and 150 mg once daily for 14 days) doses of
verubecestat were well tolerated. Verubecestat's PK profile was similar in
Japanese and non-Japanese subjects. Verubecestat also reduced mean cerebrospinal
fluid concentrations of the Aβ proteins Aβ40, Aβ42, and soluble β fragment of
amyloid precursor protein; the level of reduction was comparable between
Japanese and non-Japanese subjects. These results support the continued global
development of verubecestat as a potential disease-modifying agent for Japanese
and non-Japanese subjects who are at risk for developing AD. BACKGROUND: Prodromal Alzheimer's disease offers an opportunity to test the
effect of drugs that modify the deposition of amyloid in the brain before the
onset of dementia. Verubecestat is an orally administered β-site amyloid
precursor protein-cleaving enzyme 1 (BACE-1) inhibitor that blocks production of
amyloid-beta (Aβ). The drug did not prevent clinical progression in a trial
involving patients with mild-to-moderate dementia due to Alzheimer's disease.
METHODS: We conducted a randomized, double-blind, placebo-controlled, 104-week
trial to evaluate verubecestat at doses of 12 mg and 40 mg per day, as compared
with placebo, in patients who had memory impairment and elevated brain amyloid
levels but whose condition did not meet the case definition of dementia. The
primary outcome was the change from baseline to week 104 in the score on the
Clinical Dementia Rating Scale-Sum of Boxes (CDR-SB; scores range from 0 to 18,
with higher scores indicating worse cognition and daily function). Secondary
outcomes included other assessments of cognition and daily function.
RESULTS: The trial was terminated for futility after 1454 patients had been
enrolled; 485 had been assigned to receive verubecestat at a dose of 12 mg per
day (the 12-mg group), 484 to receive verubecestat at a dose of 40 mg per day
(the 40-mg group), and 485 to receive placebo. A total of 234 patients, 231
patients, and 239 patients per group, respectively, completed 104 weeks of the
trial regimen. The estimated mean change from baseline to week 104 in the CDR-SB
score was 1.65 in the 12-mg group, 2.02 in the 40-mg group, and 1.58 in the
placebo group (P = 0.67 for the comparison between the 12-mg group and the
placebo group and P = 0.01 for the comparison between the 40-mg group and the
placebo group), suggesting a worse outcome in the higher-dose group than in the
placebo group. The estimated rate of progression to dementia due to Alzheimer's
disease was 24.5, 25.5, and 19.3 events per 100 patient-years in the 12-mg
group, the 40-mg group, and the placebo group, respectively (hazard ratio for 40
mg vs. placebo, 1.38; 97.51% confidence interval, 1.07 to 1.79, not adjusted for
multiple comparisons), favoring placebo. Adverse events were more common in the
verubecestat groups than in the placebo group.
CONCLUSIONS: Verubecestat did not improve clinical ratings of dementia among
patients with prodromal Alzheimer's disease, and some measures suggested that
cognition and daily function were worse among patients who received verubecestat
than among those who received placebo. (Funded by Merck Sharp & Dohme;
ClinicalTrials.gov number, NCT01953601.). Conflict of interest statement: MFE, YM, TV, JK, JS, CF, EM, CL, and DM are
current or former employees of, and own/owned stock in, MSD. JLC has received
in-kind research support from Avid Radiopharmaceuticals and Teva Pharmaceuticals
and has served as a consultant to the following companies: Acadia, Accera,
Actinogen, ADAMAS, Alkahest, Allergan, Alzheon, Avanir, BiOasis Technologies,
Biogen, Boehinger-Ingelheim, Bracket, Casava, Eisai, GE Healthcare, Genentech,
Grifols, Kyowa, Lundbeck, Medavante, MSD, Nutricia, Orion, Otsuka, Pfizer, QR
Pharma, Resverlogix, Roche, Samus, Samumed, Suven, Takeda, Toyoma, United
Neuroscience. He owns stock in ADAMAS, Prana, Sonexa, MedAvante, Neurotrax, and
Neurokos. He is the copyright holder on the Neuropsychiatric Inventory. He
receives support from Keep Memory Alive and COBRE award P20GM109025. PNT has
received consulting fees from Acadia, Abbott Laboratories, AbbVie, AC Immune,
Auspex, Boehringer-Ingelheim, Chase Pharmaceuticals, Eisai, GliaCure, Insys
Therapeutics, and Pfizer. He has received consulting fees and research support
from AstraZeneca, Avanir, Eli Lilly, Lundbeck, MSD, Roche, and research support
only Amgen, Avid, Biogen, Elan, Functional Neuromodulation (f (nm)), GE
Healthcare, Genentech, Novartis, and Targacept. He has received other research
support from the NIA and Arizona Department of Health Services and holds stock
options in ADAMAS. PSA has served as a consultant to the following companies:
NeuroPhage, Eli Lilly, MSD, Avanir, Roche, Novartis, Pfizer, AstraZeneca,
Janssen, Lundbeck, Biogen, Probiodrug, Anavex, Abbvie, Janssen, Cytox, and aTyr.
He receives research support from Eli Lilly, Janssen, the Alzheimer’s
Association, and the NIH. BV has served as a consultant to the following
companies: Transition Therapeutics, Takeda, Otsuka, Lilly, Nestlé, MSD, Biogen,
and Roche. He receives research support from Abbvie, Lilly, MSD, Otsuka, Sanofi,
Alzheon, Astra-Zénéca, LPG Systems Nestlé, The Alzheimer’s Association, The
Alzheimer Drug Discovery Foundation, The European Commission, and French
Ministry of Health. |
Is Aptiganel effective for treatment of stroke? | No. Aptiganel is not efficacious in patients with acute ischemic stroke and may be harmful. | CONTEXT: Tissue plasminogen activator is the only thrombolytic agent approved in
the United States for treatment of acute ischemic stroke, and has limitations.
Aptiganel hydrochloride is a novel and selective ligand for the ion-channel site
of the N-methyl-D-aspartate receptor-channel complex and a promising
neuroprotective agent in animal models of focal brain ischemia.
OBJECTIVE: To determine whether aptiganel improves the clinical outcome for
acute ischemic stroke patients.
DESIGN: Nested phase 2/phase 3 randomized controlled trial conducted between
July 1996 and September 1997.
SETTING: One hundred fifty-six medical centers in the United States, Canada,
Australia, South Africa, England, and Scotland.
PARTICIPANTS: A total of 628 patients with hemispheric ischemic stroke (50.3%
male; mean age, 71.5 years).
INTERVENTIONS: Patients were randomly assigned within 6 hours of stroke to
receive 1 of 3 treatment regimens: high-dose aptiganel (5-mg bolus followed by
0.75 mg/h for 12 hours; n = 214); low-dose aptiganel (3-mg bolus followed by 0.5
mg/h for 12 hours; n = 200); or placebo (n = 214).
MAIN OUTCOME MEASURES: The primary efficacy end point was the Modified Rankin
Scale score at 90 days after stroke onset. Secondary end points included
mortality and change in National Institutes of Health (NIH) Stroke Scale score
at 7 days after stroke.
RESULTS: The trial was suspended by the sponsor and the independent data and
safety monitoring board because of both a lack of efficacy and a potential
imbalance in mortality. There was no improvement in outcome for either aptiganel
(low-dose or high-dose) group compared with the placebo group at 90 days (median
Modified Rankin Scale score for all 3 treatment groups = 3; P =.31). At 7 days,
placebo-treated patients exhibited slightly greater neurological improvement on
the NIH Stroke Scale than high-dose aptiganel patients (mean improvement for
placebo group, -0.8 points vs for high-dose aptiganel, 0.9 points; P =.04). The
mortality rate at 120 days in patients treated with high-dose aptiganel was
higher than that in patients who received placebo (26.3% vs 19.2%; P =.06).
Mortality in the low-dose aptiganel group was 22.5% (P =.39 vs placebo).
CONCLUSIONS: Aptiganel was not efficacious in patients with acute ischemic
stroke at either of the tested doses, and m ay be harmful. The larger proportion
of patients with favorable outcomes and lower mortality rate in the placebo
group suggest that glutamate blockade with aptiganel may have detrimental
effects in an undifferentiated population of stroke patients. During cerebral ischaemia, glutamate is released in supraphysiological amounts
and is toxic to brain tissue. This excitotoxicity is mediated by several
glutamate receptor subtypes, including the ionotropic N-methyl-D-aspartate
(NMDA) and alpha-amino-3-hydroxy-5-methylisoxazole-4-propionic acid (AMPA)
receptors. Clinical trials of drugs that block the NMDA receptor in acute
ischaemic stroke have been disappointing. No improvement in clinical outcome of
stroke has been seen with competitive NMDA antagonists (selfotel) and
non-competitive NMDA antagonists (dextrorphan, GV150526, aptiganel and
eliprodil). The AMPA receptor differs in important ways from the NMDA receptor.
It is the principal mediator of fast excitatory neurotransmission. This
ligand-gated cation channel is primarily permeable to sodium rather than
calcium. It is found in grey and white matter. It is expressed by
oligodendrocytes. This distribution may provide neuroprotection for both grey
and white matter. In a variety of animal models, reduction in infarct volume
with AMPA blockade has been demonstrated. AMPA antagonists also show benefit in
spinal cord ischaemia and trauma. The clinical development of safe and effective
AMPA blockers has been hampered by poor water solubility and associated renal
toxicity. A novel, highly water-soluble, competitive AMPA receptor antagonist,
YM872
([2,3-dioxo-7-(1H-imidazol-1-yl)-6-nitro-1,2,3,4-tetrahydroquinoxalin-1-yl]acetic
acid monohydrate; Yamanouchi), has been identified. Phase I clinical trial data
indicate that this agent can be safely administered in young and elderly
subjects. Sedation and other CNS associated adverse events determine the ceiling
dose and become more problematic with infusion times exceeding 24 h. Phase II
studies of YM872 in acute ischaemic stroke are ongoing. Glutamate N-methyl-D-aspartate (NMDA) receptor antagonists (competitive receptor
antagonists, ion channel blockers, and glycine antagonists)--such as selfotel,
aptiganel, eliprodil, licostinel and gavestinel--failed to show efficacy in
clinical trials of stroke or traumatic brain injury. This failure has been
attributed to the deficient properties of the molecules that entered human
trials and to inappropriate design of clinical studies. In this article we
hypothesise that glutamate may be involved in the acute neurodestructive phase
that occurs immediately after traumatic or ischaemic injury (excitotoxicity),
but that, after this period, it assumes its normal physiological functions,
which include promotion of neuronal survival. We propose that NMDA receptor
antagonists failed stroke and traumatic brain injury trials in human beings
because blockade of synaptic transmission mediated by NMDA receptors hinders
neuronal survival. BACKGROUND: Focal cerebral ischaemia causes release of excitatory amino acid
(EAA) neurotransmitters, principally glutamate, with resultant over-stimulation
of EAA receptors and downstream pathways. Excess glutamate release is a pivotal
event in the evolution of irreversible ischaemic damage in animal models of
ischaemia, and drugs that modulate glutamate action either by inhibiting its
release, or blocking post-synaptic receptors, are potent neuroprotective agents.
Many clinical trials with EAA modulating drugs have been conducted, none
individually demonstrating efficacy.
OBJECTIVES: To synthesise all the available data on all different classes of EAA
modulators and to evaluate evidence of effects on outcome systematically.
SEARCH STRATEGY: Relevant trials were identified in the Specialised Register of
Controlled Trials (last searched May 2001). In addition, MEDLINE and EMBASE
online searches for the terms "neuroprotection" (and its variants),
"neuroprotective agent", for all individual drugs and drug classes included in
the review, hand searches of conference proceedings from European,
International, American Heart Association and Princeton conferences on Stroke,
American Neurological Association and American Academy of Neurology meetings
from 1992-2001, and direct contact with individual investigators and
pharmaceutical companies.
SELECTION CRITERIA: Trials were included if they were randomised, controlled
studies giving agents with pharmacological properties that included modification
of release of EAAs, or blockade of EAA receptors, in stroke within 24h of onset.
Efficacy analysis was restricted to trials with a parallel group design: dose
escalation studies were excluded. Intention-to-treat analyses were performed on
all data. Outcome had to be reported in terms of death or dependence 1-12 months
after the acute event.
DATA COLLECTION AND ANALYSIS: Data were available for 36 of 41 relevant trials
identified, involving 11,209 subjects. Data were unavailable for 632
participants (517 in trials fulfilling criteria for efficacy analysis). Seven
trials did not report disability data, which were available for 29 trials
involving 10,802 subjects. Twenty one of these trials, involving 10,342
subjects, were parallel group studies included in the primary efficacy analysis.
Efficacy analysis included data derived from 9 trials not primarily designed to
assess efficacy (1022 subjects). The primary (efficacy) end-point was the
proportion of patients dead or disabled at final follow-up (defined by Barthel
Index<60 at 3 months by preference). Mortality was a secondary end-point. Drugs
were considered as individual agents, and also grouped principally into
categories of ion channel modulators (glutamate release inhibition) and NMDA
antagonists.
MAIN RESULTS: There was no significant heterogeneity of outcome amongst
individual drugs, or of drug classes either for the primary efficacy analysis
(death or dependence) or for mortality at final follow-up. For the primary
efficacy analysis, odds of death or dependence were 1.03 [95% confidence
interval 0.96-1.12], and for mortality 1.02 [0.92-1.12]. Neither ion channel
modulators (death or dependence 1.02 [0.90-1.16]) nor NMDA antagonists (death or
dependence 1.05 [0.95-1.16]) differed from the principal analysis including all
compounds. Trends for increased mortality with three NMDA antagonists were seen
- selfotel (OR 1.19 [0.81-1.74]), aptiganel (OR 1.32 [0.91-1.93]) and gavestinel
(OR 1.12 [0.95-1.32]) - but this did not achieve significance for the NMDA
antagonists considered as a class (1.09 [0.96-1.23]). Aptiganel was also
associated with a trend towards worse functional outcome (OR 1.20 [0.88-1.65])
although this was not the case for either of the other two compounds. No
statistically significant detriment of psychotomimetic NMDA antagonists was
found, although a trend towards higher mortality in this sub-group was seen (OR
1.25 [0.96-1.64]).
REVIEWER'S CONCLUSIONS: There was no evidence of significant benefit or harm
from drugs modulating excitatory amino acid action. Reductio]).
REVIEWER'S CONCLUSIONS: There was no evidence of significant benefit or harm
from drugs modulating excitatory amino acid action. Reduction of death or
dependence by 8% or more has been excluded for gavestinel and lubeluzole, which
contribute most of the data for this review. However, mechanistic understanding
of neuroprotection is too poor to extrapolate from these two failed development
plans to all glutamate modulators. Further clinical trials of neuroprotective
agents remain justified, since confidence limits around estimates of effect
remain wide for most agents, and cannot reliably exclude benefit. Although
numbers of patients are too small to confirm or refute a trend towards increased
mortality with some NMDA antagonists, further commercial development of these
agents is exceedingly unlikely. |
Is indinavir effective for treatment of amyotrophic lateral sclerosis? | No, indinavir is not effective for treatment of amyotrophic lateral sclerosis. | |
Is there an increased risk for meningiomas in childhood leukemia survivors? | Yes, the risk of meningiomas is higher in children treated with cranial irradiation for leukemia. | We report a case of meningioma diagnosed 23 years after high-dose cranial and
whole-body irradiation for the treatment of acute lymphocytic leukemia (ALL).
Radiotherapy in this case also caused early radiation injury to the lenses and
the pituitary gland, with growth retardation and mineralizing angiopathy.
Radiation-induced meningiomas are more commonly maligt, more commonly
multiple, and more likely to recur after resection than non-radiation-induced
meningiomas. Survivors of childhood ALL treated with high-dose cranial
irradiation are at risk both for early radiation injury in radiosensitive
organs, such as the lens and pituitary gland, and for the later development of a
radiation-induced meningioma. BACKGROUND: Acute lymphoblastic leukemia (ALL) is the most common childhood
maligcy. Although it was considered to be a poor prognostic disease, modern
treatment protocols (aggressive chemotherapy and prophylactic cranial
irradiation) have resulted in dramatically improved survival rates. In a group
of low-risk ALL patients, the 5-year survival rate is estimated to be 85%.
However, ALL patients who undergo this treatment are at risk of developing
secondary neoplasms related to treatment, which has become an increasingly
recognized problem.
CASE DESCRIPTION: A 3-year-old boy with ALL was successfully treated with
chemotherapy (vincristine, prednisolone, mercaptopurine and methotrexate) and
prophylactic cranial irradiation (total 18 Gy). At the age of 23, he was
admitted to our hospital for weakness in the right leg. Computed tomography and
magnetic resoce imaging revealed a parasagittal tumor of the left
frontoparietal lobe with perifocal edema. The tumor was completely removed
surgically and pathohistologically diagnosed as atypical meningioma.
CONCLUSION: Long-term survivors who received radiotherapy for ALL in childhood
are at risk for late complications, including radiation-induced meningioma.
Therefore, careful follow-up neurological examinations, for example magnetic
resoce imaging, are indicated in these patients. In addition, late
complications should be taken into account during the initial planning of
prophylactic radiotheraphy dosage, which has implications for informed consent
of the patient. BACKGROUND: Most survivors of childhood acute lymphoblastic leukemia (ALL) and
T-cell lymphoma (T-NHL) treated before 1990 received cranial radiation. This
study assessed the occurrence of second tumors in irradiated and non-irradiated
survivors.
METHODS: Two hundred and ten survivors of ALL and T-NHL were treated between
1974 and 1997 by several protocols. Imaging (MRI, CT) was performed every 3-6
years in 76/88 irradiated and 74/122 non-irradiated patients for the last 20
years.
RESULTS: From January 1998 through 2004, meningiomas were detected in 16
survivors (8 female, 8 male) at age 20-39 years (median 28.7); 15 were
asymptomatic. Cranial imaging done 2-8 years previously in 11 revealed no
abnormalities. Fifteen had been diagnosed with ALL or T-NHL 10-29 years earlier
(median 21) and received cranial irradiation (24 Gy in 14) at age 2-14 years
(median 7.6). Fifteen tumors arose in the convexity. Three patients had multiple
lesions. Complete resection was performed in 12 patients, with one complication.
One patient had a recurrence, and four with small tumors are under surveillance.
Only one low-grade glioma and two basal-cell carcinomas were found. Only one of
the 74 non-irradiated patients (median follow-up 14 years) developed meningioma.
The Kaplan-Meier estimate of incidence of meningioma was 14.8+/-7.6 at 20 years.
CONCLUSIONS: Survivors of childhood ALL treated with cranial radiation require
prolonged surveillance because of a high incidence of late meningiomas. Early
detection, when the tumor is still small, facilitates resection and may reduce
complications. While the prognosis of acute childhood leukemia has improved, long-term
survivors are increasingly experiencing late effects of the treatment. Cranially
irradiated survivors are predisposed to the development of CNS tumors. Our aim
was to describe the incidence of secondary brain tumors and to define the
significance of treatment-related risk factors and host characteristics in a
cohort of childhood leukemia survivors. Our cohort consisted of 60 consecutive
cranially irradiated adult survivors of childhood leukemia treated in Oulu
University Hospital (Oulu, Finland); MRI of the brain was performed on 49. The
sites of the tumors, their histology, and details of the leukemia treatment were
determined. Of the 49 patients, 11 (22%) 1-8 years of age at the time of
diagnosis developed meningioma later in life, while no other brain tumors were
seen. In this cohort, the development of meningioma seemed to show undisputable
linkage with long latency periods (mean, 25 years; range, 14-34 years) and an
increasing incidence 20 years after the treatment (47%). Three patients had
multiple meningiomas, two had recurrent disease, and one had an atypical
meningioma. Age at the time of irradiation, gender, or cumulative doses of
chemotherapeutic agents showed no significant association with the development
of meningiomas. The high incidence of meningiomas in this study was associated
with long follow-up periods. Although the cohort is small, it seems probable
that the increasing incidence of meningioma will shadow the future of cranially
irradiated leukemia survivors. Systematic brain imaging after the treatment is
therefore justifiable. Meningiomas are among the most common brain tumors in adults. They are most
commonly located over the cerebral convexities and are infrequently found in an
intraventricular location. Ionizing cranial radiation is a risk factor for late
occurrence of meningiomas within the radiation field. While pathologic grading
of meningiomas is straightforward, significant variability often exists between
pathologists in applying standard grading criteria. This has implications for
prognosis. Radiation-induced meningiomas may also have predilection to recur.
The authors describe a case of an intraventricular meningioma occurring 23 years
after cranial irradiation for childhood acute lymphoblastic leukemia. BACKGROUND: The occurrence of subsequent neoplasms has direct impact on the
quantity and quality of life in cancer survivors. We have expanded our analysis
of these events in the Childhood Cancer Survivor Study (CCSS) to better
understand the occurrence of these events as the survivor population ages.
METHODS: The incidence of and risk for subsequent neoplasms occurring 5 years or
more after the childhood cancer diagnosis were determined among 14,359 5-year
survivors in the CCSS who were treated from 1970 through 1986 and who were at a
median age of 30 years (range = 5-56 years) for this analysis. At 30 years after
childhood cancer diagnosis, we calculated cumulative incidence at 30 years of
subsequent neoplasms and calculated standardized incidence ratios (SIRs), excess
absolute risks (EARs) for invasive second maligt neoplasms, and relative
risks for subsequent neoplasms by use of multivariable Poisson regression.
RESULTS: Among 14,359 5-year survivors, 1402 subsequently developed 2703
neoplasms. Cumulative incidence at 30 years after the childhood cancer diagnosis
was 20.5% (95% confidence interval [CI] = 19.1% to 21.8%) for all subsequent
neoplasms, 7.9% (95% CI = 7.2% to 8.5%) for second maligt neoplasms
(excluding nonmelanoma skin cancer), 9.1% (95% CI = 8.1% to 10.1%) for
nonmelanoma skin cancer, and 3.1% (95% CI = 2.5% to 3.8%) for meningioma. Excess
risk was evident for all primary diagnoses (EAR = 2.6 per 1000 person-years, 95%
CI = 2.4 to 2.9 per 1000 person-years; SIR = 6.0, 95% CI = 5.5 to 6.4), with the
highest being for Hodgkin lymphoma (SIR = 8.7, 95% CI = 7.7 to 9.8) and Ewing
sarcoma (SIR = 8.5, 95% CI = 6.2 to 11.7). In the Poisson multivariable
analysis, female sex, older age at diagnosis, earlier treatment era, diagnosis
of Hodgkin lymphoma, and treatment with radiation therapy were associated with
increased risk of subsequent neoplasm.
CONCLUSIONS: As childhood cancer survivors progress through adulthood, risk of
subsequent neoplasms increases. Patients surviving Hodgkin lymphoma are at
greatest risk. There is no evidence of risk reduction with increasing duration
of follow-up. BACKGROUND: Children treated with cranial radiotherapy (CRT) for leukemia are at
risk of developing central nervous system injuries. Magnetic resoce imaging
(MRI) represents the examination method of choice for evaluating
radiation-induced brain complications. The purpose of this report is to describe
the spectrum of MRI abnormalities detected in a group of survivors of leukemia
treated with cranial irradiation.
PROCEDURES: In this cross-sectional, single center study, 56 patients (median
age at follow-up 19 years) receiving CRT as cranial prophylaxis (CP) included in
the leukemia protocol (total dose 1,800-2,400 cGy) and/or in the total body
irradiation regimen (990-1,200 cGy) before hematopoietic stem cell transplant,
were evaluated by MRI after a median interval of 11 years (range 2-27) following
CRT.
RESULTS: Fifty-nine MRI abnormalities (32 cavernomas, nine focal areas of
gliosis, seven dystrophic mineralizations, five cerebral atrophies, four
pituitary atrophies, one diffuse radiation leukoencephalopathy, and one
meningioma) were found in 43 patients. The longest interval between CRT and MRI
and oldest age at follow-up represented the two risk factors that were
statistically associated with MRI lesions (P = 0.032 and 0.033, respectively).
Cerebral cavernomas (CC) were the most frequent MRI abnormalities (57%). All
patients with CC were asymptomatic at diagnosis and during follow-up, except one
who had aspecific neurological manifestations and micro hemorrhages.
CONCLUSIONS: These results confirm that total doses and modalities of
fractionation dose of CRT were not significantly associated with MRI
abnormalities. Moreover, in our experience none of the patients developed
neurological symptoms related to MRI abnormalities, and furthermore, the CC
remained substantially stable during follow-up. Author information:
(1)MacFeeters Hamilton Centre for Neuro-Oncology Research, Princess Margaret
Cancer Centre, University Health Network, Toronto, ON, Canada, M5G 1L7.
(2)Department of Surgery, Division of Neurosurgery, University of Toronto,
Toronto, ON, Canada, M5S 1A8.
(3)Princess Margaret Cancer Centre, Toronto, ON, Canada, M5G 2M9.
(4)Department of Laboratory Medicine and Pathobiology, University of Toronto,
Toronto, ON, Canada, M5S 1A8.
(5)Department of Neuropathology, Institute of PathologyUniversity Hospital
Heidelberg, Heidelberg, 69120, Germany.
(6)Clinical Cooperation Unit Neuropathology, German Consortium for Translational
Cancer Research (DKTK) German Cancer Research Center (DKFZ), Heidelberg, 69120,
Germany.
(7)Developmental & Stem Cell Biology Program, Arthur and Sonia Labatt Brain
Tumour Research Centre, The Hospital for Sick Children, Toronto, ON, Canada, M5G
1L7.
(8)MacFeeters Hamilton Centre for Neuro-Oncology Research, Princess Margaret
Cancer Centre, University Health Network, Toronto, ON, Canada, M5G 1L7.
[email protected].
(9)Princess Margaret Cancer Centre, Toronto, ON, Canada, M5G 2M9.
[email protected].
(10)Department of Laboratory Medicine and Pathobiology, University of Toronto,
Toronto, ON, Canada, M5S 1A8. [email protected].
(11)MacFeeters Hamilton Centre for Neuro-Oncology Research, Princess Margaret
Cancer Centre, University Health Network, Toronto, ON, Canada, M5G 1L7.
[email protected].
(12)Department of Surgery, Division of Neurosurgery, University of Toronto,
Toronto, ON, Canada, M5S 1A8. [email protected].
(13)Princess Margaret Cancer Centre, Toronto, ON, Canada, M5G 2M9.
[email protected]. PURPOSE: Radiation-induced meningioma is a known late effect of cranial
radiation therapy. Cranial magnetic resoce imaging (MRI) can detect small
meningiomas, but its potential value as a screening tool is unknown.
METHODS AND MATERIALS: MRI was used to screen asymptomatic survivors of
childhood acute lymphoblastic leukemia (ALL) treated with cranial radiation
therapy ≥10 years previously. The incidence of radiation-induced meningioma and
outcomes of this group were compared with a historical cohort of survivors with
the same exposure who underwent imaging only to investigate clinical signs or
symptoms.
RESULTS: One hundred seventy-six childhood leukemia survivors were included in
this study: 70 in the screening group and 106 unscreened. Screening MRI was
performed a median of 25 years after radiation therapy and detected meningioma
in 15 (21.4%). In the unscreened group, 17 patients (16.0%) had neurologic
symptoms leading to an MRI a median interval of 24 years after radiation
therapy, 9 of whom (8.5%) were diagnosed with meningioma. There was no
significant difference between screened versus unscreened patients in the size
of meningioma (mean diameter, 1.6 cm vs 2.6 cm; P = .13), meningioma incidence
(7.4% vs 4.0% at 25 years; P = .19), or extent of resection. Three patients had
persistent neurologic symptoms in the unscreened group versus none among
screened patients (P = .28).
CONCLUSIONS: Screening MRI was able to detect small meningiomas that were not
clinically apparent; however, we could not demonstrate a significant improvement
in the chance of total resection or a significant decrease in morbidity. A
larger sample could clarify potential reduction in neurologic sequelae
associated with screening. |
List the clinical characteristics of the Smith-Kingsmore syndrome (SKS) | Smith-Kingsmore syndrome (SKS) OMIM #616638, also known as MINDS syndrome (ORPHA 457485), is a rare autosomal dominant disorder reported so far in 23 patients. SKS is characterized by intellectual disability, macrocephaly/hemi/megalencephaly, and seizures. It is also associated with a pattern of facial dysmorphology and other non-neurological features. | Author information:
(1)Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER),
ISCIII, Madrid, Spain.
(2)Molecular Endocrinology Section, Overgrowth Syndromes Laboratory, Instituto
de Genética Médica y Molecular (INGEMM), IdiPAZ, Hospital Universitario la Paz,
Universidad Autónoma de Madrid (UAM), Madrid, Spain.
(3)Vascular Malformations Section, Instituto de Genética Médica y Molecular
(INGEMM), IdiPAZ, Hospital Universitario la Paz, Universidad Autónoma de Madrid
(UAM), Madrid, Spain.
(4)Clinical Genetics Section, Instituto de Genética Médica y Molecular (INGEMM),
IdiPAZ, Hospital Universitario la Paz, Universidad Autónoma de Madrid (UAM),
Madrid, Spain.
(5)Structural and Functional Genomics Section, Instituto de Genética Médica y
Molecular (INGEMM), IdiPAZ, Hospital Universitario la Paz, Universidad Autónoma
de Madrid (UAM), Madrid, Spain.
(6)Bioinformatics Section, Instituto de Genética Médica y Molecular (INGEMM),
IdiPAZ, Hospital Universitario la Paz, Universidad Autónoma de Madrid (UAM),
Madrid, Spain.
(7)IIB, Instituto de Investigación "Alberto Sols", Universidad Autónoma de
Madrid (UAM), Madrid, Spain. |
What is ORMD-0801? | ORMD-0801 is an oral insulin capsule. Treatment with ORMD-0801 was associated with a significant 24.4% reduction in the frequencies of glucose readings >200 mg/dL (60.1 +- 7.9% pretreatment vs. 45.4 +- 4.9% during ORMD-0801 treatment; p = 0.023) and a significant mean 16.6% decrease in glucose area under the curve (AUC) (66055 +- 5547 mg/dL/24 hours vs. 55060 +- 3068 mg/dL/24 hours, p = 0.023), with a greater decrease during the early evening hours. When used in conjunction with subcutaneous insulin injections, ORMD-0801 was well tolerated and effectively reduced glycemia throughout the day. | The unpredictable behavior of uncontrolled type 1 diabetes often involves
frequent swings in blood glucose levels that impact maintece of a daily
routine. An intensified insulin regimen is often unsuccessful, while other
therapeutic options, such as amylin analog injections, use of continuous glucose
sensors, and islet or pancreas transplantation are of limited clinical use. In
efforts to provide patients with a more compliable treatment method, Oramed
Pharmaceuticals tested the capacity of its oral insulin capsule (ORMD-0801, 8 mg
insulin) in addressing this resistant clinical state. Eight Type I diabetes
patients with uncontrolled diabetes (HbA1c: 7.5-10%) were monitored throughout
the 15-day study period by means of a blind continuous glucose monitoring
device. Baseline patient blood glucose behavior was monitored and recorded over
a five-day pretreatment screening period. During the ensuing ten-day treatment
phase, patients were asked to conduct themselves as usual and to self-administer
an oral insulin capsule three times daily, just prior to meal intake. CGM data
sufficient for pharmacodynamics analyses were obtained from 6 of the 8 subjects.
Treatment with ORMD-0801 was associated with a significant 24.4% reduction in
the frequencies of glucose readings >200 mg/dL (60.1 ± 7.9% pretreatment vs.
45.4 ± 4.9% during ORMD-0801 treatment; p = 0.023) and a significant mean 16.6%
decrease in glucose area under the curve (AUC) (66055 ± 5547 mg/dL/24 hours vs.
55060 ± 3068 mg/dL/24 hours, p = 0.023), with a greater decrease during the
early evening hours. In conclusion, ORMD-0801 oral insulin capsules in
conjunction with subcutaneous insulin injections, well tolerated and effectively
reduced glycemia throughout the day.
TRIAL REGISTRATION: Clinicaltrials.gov NCT00867594. |
Does saracatinib promote oncogenesis? | No, saracatinib has antitumor activity. | Src is a nonreceptor tyrosine kinase involved in the cross-talk and mediation of
many signaling pathways that promote cell proliferation, adhesion, invasion,
migration, and tumorigenesis. Increased Src activity has been reported in many
types of human cancer, including gastric cancer. Therefore, this factor has been
identified as a promising therapeutic target for cancer treatments, and
targeting Src in gastric cancer is predicted to have potent effects. We
evaluated the antitumor effect of a c-Src/Abl kinase inhibitor, saracatinib
(AZD0530), alone or combined with chemotherapeutic agents in gastric cancer cell
lines and a NCI-N87 xenograft model. Among 10 gastric cancer cell lines,
saracatinib specifically inhibited the growth and migration/invasion of SNU216
and NCI-N87 cells. Saracatinib blocked the Src/FAK, HER family, and oncogenic
signaling pathways, and it induced G(1) arrest and apoptosis in SNU216 and
NCI-N87 cells. Apoptosis required induction of the proapoptotic BCL2 family
member Bim. Knockdown of Bim using siRNA decreased apoptosis induced by
treatment with saracatinib, suggesting that Bim has an important role in
saracatinib-induced apoptosis. Saracatinib enhanced the effects of lapatinib, an
EGFR/HER2 dual inhibitor, in SNU216 and NCI-N87 cells. Furthermore, combined
treatment with saracatinib and 5-fluorouracil (5-FU) or cisplatin exerted
synergistic effects in both saracatinib-sensitive and saracatinib-resistant
cells. Consistent with our in vitro findings, cotreatment with saracatinib and
5-FU resulted in enhanced antitumor activity in the NCI-N87 xenografts. These
data indicate that the inhibition of Src kinase activity by saracatinib alone or
in combination with other agents can be a strategy to target gastric cancer. |
Is BCL11B involved in schizophrenia? | Yes, BCL11B is associated with attention, memory, executive function and antipsychotic-induced schizophrenia. | SATB2 is associated with schizophrenia and is an important transcription factor
regulating neocortical organization and circuitry. Rare mutations in SATB2 cause
a syndrome that includes developmental delay, and mouse studies identify an
important role for SATB2 in learning and memory. Interacting partners BCL11B and
GATAD2A are also schizophrenia risk genes indicating that other genes
interacting with or are regulated by SATB2 are making a contribution to
schizophrenia and cognition. We used data from Satb2 mouse models to generate
three gene-sets that contain genes either functionally related to SATB2 or
targeted by SATB2 at different stages of development. Each was tested for
enrichment using the largest available genome-wide association studies (GWAS)
datasets for schizophrenia and educational attainment (EA) and enrichment
analysis was also performed for schizophrenia and other neurodevelopmental
disorders using data from rare variant sequencing studies. These SATB2 gene-sets
were enriched for genes containing common variants associated with schizophrenia
and EA, and were enriched for genes containing rare variants reported in studies
of schizophrenia, autism and intellectual disability. In the developing cortex,
genes targeted by SATB2 based on ChIP-seq data, and functionally affected when
SATB2 is not expressed based on differential expression analysis using RNA-seq
data, show strong enrichment for genes associated with EA. For genes expressed
in the hippocampus or at the synapse, those targeted by SATB2 are more strongly
enriched for genes associated EA than gene-sets not targeted by SATB2. This
study demonstrates that single gene findings from GWAS can provide important
insights to pathobiological processes. In this case we find evidence that genes
influenced by SATB2 and involved in synaptic transmission, axon guidance and
formation of the corpus callosum are contributing to schizophrenia and
cognition. |
What is Synucleinopathy? | Synucleinopathy is an autosomal-dominant disease characterised by misfolding of presynaptic synuclein and the formation of Lewy bodies with ubiquitin-ligase activity. | Synucleinopathies are a group of neurodegenerative diseases that share a common
pathological lesion of intracellular protein inclusions largely composed by
aggregates of alpha-synuclein protein. Accumulating evidence, including genome
wide association studies, has implicated alpha-synuclein (SNCA) gene in the
etiology of synucleinopathies. However, the precise variants within SNCA gene
that contribute to the sporadic forms of Parkinson's disease (PD), dementia with
Lewy bodies (DLB), multiple system atrophy (MSA), and other synucleinopathies
and their molecular mechanisms of action remain elusive. It has been suggested
that SNCA expression levels are critical for the development of these diseases.
Here, we review several model systems that have been developed to advance the
understanding of the role of SNCA expression levels in the etiology of
synucleinopathies. We also describe different molecular mechanisms that regulate
SNCA gene expression and discuss possible strategies for SNCA down-regulation as
means for therapeutic approaches. Finally, we highlight some examples that
underscore the relationships between the genetic association findings and the
regulatory mechanisms of SNCA expression, which suggest that genetic variability
in SNCA locus is directly responsible, at least in part, to the changes in gene
expression and explain the reported associations of SNCA with synucleinopathies.
Future studies utilizing induced pluripotent stem cells (iPSCs)-derived neuronal
lines and genome editing by CRISPR/Cas9, will allow us to validate,
characterize, and manipulate the effects of particular cis-genetic variants on
SNCA expression. Moreover, this model system will enable us to compare different
neuronal and glial lineages involved in synucleinopathies representing an
attractive strategy to elucidate-common and specific-SNCA-genetic variants,
regulatory mechanisms, and vulnerable expression levels underlying
synucleinopathy spectrum disorders. This forthcoming knowledge will support the
development of precision medicine for synucleinopathies. The accumulation of abnormal α-synuclein is the major histopathological feature
of Lewy body disease and multiple system atrophy (MSA), which are referred to as
synucleinopathies. Cytoplasmic degradation systems, such as the
autophagy-lysosome and proteasome pathways, are involved in their pathogenesis.
Autophagy is tightly regulated by several upstream proteins including
UNC-51-like kinase 1/2, beclin1, vacuolar protein sorting-associated protein 34
and autophagy/beclin1 regulator 1 (AMBRA1). Recently, we revealed that both
cortical and brainstem-type Lewy bodies were immunopositive for several upstream
proteins of autophagy. Therefore, we conducted the present study to elucidate
the role of upstream proteins of autophagy in the pathogenesis of MSA.
Pathological and biochemical analyses using human brain samples revealed that
AMBRA1 is a component of the pathological hallmarks of MSA and upstream proteins
of autophagy are impaired in the MSA brain. In vitro and in vivo analyses
revealed a ninefold stronger affinity of AMBRA1 with α-synuclein phosphorylated
at serine 129 compared with non-phosphorylated α-synuclein. Furthermore, a weak
but significant correlation between AMBRA1 overexpression and reduction of
abnormal α-synuclein was observed. Silencing AMBRA1 function caused aggregates
of α-synuclein in the cytoplasm of mouse primary cultured neurons, which was
simulated by the treatment of Bafilomycin, an autophagy inhibitor. Our results
demonstrated for the first time that AMBRA1 is a novel hub binding protein of
α-synuclein and plays a central role in the pathogenesis of MSA through the
degradative dynamics of α-synuclein. These results raise the possibility that
molecular modulation targeting AMBRA1 can be a promising candidate for the
treatment of synucleinopathies. The deposition of misfolded β-sheet enriched amyloid protein is a shared feature
of many neurodegenerative diseases. Recent studies demonstrated the existence of
conformationally diverse strains as a common property for multiple amyloidogenic
proteins including α-Synuclein (α-Syn). α-Syn is misfolded and aggregated in a
group of neurodegenerative diseases collectively known as α-Synucleinopathies,
which include Parkinson's disease (PD), dementia with Lewy body, multiple system
atrophy and also a subset of Alzheimer's disease patients with concomitant
PD-like Lewy bodies and neurites. While sharing the same pathological protein,
different α-Synucleinopathies demonstrate distinct clinical and pathological
phenotypes, which could result from the existence of diverse pathological α-Syn
strains in patients. In this review, we summarized the characteristics of
different α-Synucleinopathies and α-Syn strains generated with recombit α-Syn
monomers. We also make predictions of α-Syn strains that could potentially exist
in patients based on the knowledge from other amyloid proteins and the clinical
and pathological features of different α-Synucleinopathies. Synucleinopathies are a spectrum of neurodegenerative diseases characterized by
the intracellular deposition of the protein α-synuclein leading to multiple
outcomes, including dementia and Parkinsonism. Recent findings support the
notion that across the spectrum of synucleinopathies there exist diverse but
specific biochemical modifications and/or structural conformations of
α-synuclein, which would give rise to protein strain specific prion-like
intercellular transmission, a proposed model that could explain
synucleinopathies disease progression. Herein, we characterized a panel of
antibodies with epitopes within both the C- and N- termini of α-synuclein. A
comprehensive analysis of human pathological tissue and mouse models of
synucleinopathy with these antibodies support the notion that α-synuclein exists
in distinct modified forms and/or structural variants. Furthermore, these
well-characterized and specific tools allow the investigation of biochemical
changes associated with α-synuclein inclusion formation. We have identified
several antibodies of interest with diverse staining and epitope properties that
will prove useful in future investigations of strain specific disease
progression and the development of targeted immunotherapeutic approaches to
synucleinopathies. The abnormal accumulation of α-synuclein aggregates in neurons, nerve fibers, or
glial cells is the hallmark of a group of neurodegenerative diseases known
collectively as α-synucleinopathies. Clinical, neuropathological, and
experimental evidence strongly suggests that α-synuclein plays a role not only
as a trigger of pathological processes at disease inception, but also as a
mediator of pathological spreading during disease progression. Specific
properties of α-synuclein, such as its ability to pass from one neuron to
another, its tendency to aggregate, and its potential to generate
self-propagating species, have been described and elucidated in animal models
and may contribute to the relentless exacerbation of Parkinson's disease
pathology in patients. Animal models used for studying α-synuclein accumulation,
aggregation, and propagation are mostly based on three approaches: (1)
intra-parenchymal inoculations of exogenous α-synuclein (e.g., synthetic
α-synuclein fibrils), (2) transgenic mice, and (3) animals (mice or rats) in
which α-synuclein overexpression is induced by viral vector injections. Whereas
pathological α-synuclein changes are consistently observed in these models,
important differences are also found. In particular, pronounced pathology in
transgenic mice and viral vector-injected animals does not appear to involve
self-propagating α-synuclein species. A critical discussion of these models
reveals their strengths and limitations and provides the basis for
recommendations concerning their use for future investigations. |
Which receptor is modulated with Siponimod? | Siponimod is a functional sphingosine-1-phosphate (S1P) antagonist. | BACKGROUND: Siponimod is an oral selective modulator of sphingosine 1-phosphate
receptor types 1 and type 5, with an elimination half-life leading to washout in
7 days. We aimed to determine the dose-response relation of siponimod in terms
of its effects on brain MRI lesion activity and characterise safety and
tolerability in patients with relapsing-remitting multiple sclerosis.
METHODS: In this double-blind, adaptive dose-ranging phase 2 study, we enrolled
adults (aged 18-55 years) with relapsing-remitting multiple sclerosis at 73
medical centres in Europe and North America. We tested two patient cohorts
sequentially, separated by an interim analysis at 3 months. We randomly
allocated patients in cohort 1 (1:1:1:1) to receive once-daily siponimod 10 mg,
2 mg, or 0·5 mg, or placebo for 6 months. We randomly allocated patients in
cohort 2 (4:4:1) to siponimod 1·25 mg, siponimod 0·25 mg, or placebo once-daily
for 3 months. Randomisation was done with a central, automated system and
patients and investigators were masked to treatment assignment. The primary
endpoint was dose-response, assessed by percentage reduction in monthly number
of combined unique active lesions at 3 months for siponimod versus placebo; this
endpoint was analysed by a multiple comparison procedure with modelling
techniques in all patients with at least one MRI scan up to 3 months. We
assessed safety in all patients who received at least one dose of study drug.
This study is registered with ClinicalTrials.gov, number NCT00879658.
FINDINGS: Between March 30, 2009, and Oct 22, 2010, we recruited 188 patients
into cohort 1 and 109 patients into cohort 2. We showed a dose-response relation
(p=0·0001) across the five doses of siponimod, with reductions in combined
unique active lesions at 3 months compared with placebo of 35% (95% CI 17-57)
for siponimod 0·25 mg (51 patients included in the primary endpoint analysis),
50% (29-69) for siponimod 0·5 mg (43 patients), 66% (48-80) for siponimod 1·25
mg (42 patients), 72% (57-84) for siponimod 2 mg (45 patients), and 82% (70-90)
for siponimod 10 mg (44 patients). In patients treated for 6 months, 37 (86%) of
43 patients who received siponimod 0·5 mg had adverse events (eight serious), as
did 48 (98%) of 49 patients who received siponimod 2 mg (four serious), 48 (96%)
of 50 patients who received siponimod 10 mg (three serious), and 36 (80%) of 45
controls (none serious). For individuals treated to 3 months, 38 (74%) of 51
patients who received siponimod 0·25 mg had adverse events (none serious), as
did 29 (69%) of 42 patients who received siponimod 1·25 mg (two serious) and 13
(81%) of 16 controls (none serious).
INTERPRETATION: Therapeutic effects of siponimod on MRI lesion activity in
model-based analyses and its tolerability in relapsing-remitting multiple
sclerosis warrant investigation in a phase 3 trial.
FUNDING: Novartis Pharma AG. Fingolimod, a sphingosine 1-phosphate (S1P) receptor subtype 1, 3, 4 and 5
modulator, has been used for the treatment of patients with relapsing forms of
multiple sclerosis, but atrioventricular conduction block and/or QT-interval
prolongation have been reported in some patients after the first dose. In this
study, we directly compared the electropharmacological profiles of fingolimod
with those of siponimod, a modulator of sphingosine 1-phosphate receptor subtype
1 and 5, using in vivo guinea-pig model and in vitro human ether-a-go-go-related
gene (hERG) assay to better understand the onset mechanisms of the clinically
observed adverse events. Fingolimod (0.01 and 0.1mg/kg) or siponimod (0.001 and
0.01mg/kg) was intravenously infused over 10min to the halothane-anaesthetized
guinea pigs (n=4), whereas the effects of fingolimod (1μmol/L) and siponimod
(1μmol/L) on hERG current were examined (n=3). The high doses of fingolimod and
siponimod induced atrioventricular conduction block, whereas the low dose of
siponimod prolonged PR interval, which was not observed by that of fingolimod.
The high dose of fingolimod prolonged QT interval, which was not observed by
either dose of siponimod. Meanwhile, fingolimod significantly inhibited hERG
current, which was not observed by siponimod. These results suggest that S1P
receptor subtype 1 in the heart could be one of the candidates for fingolimod-
and siponimod-induced atrioventricular conduction block since S1P receptor
subtype 5 is localized at the brain, and that direct IKr inhibition may play a
key role in fingolimod-induced QT-interval prolongation. Development of sphingosine-1-phosphate receptor 1 (S1P1) modulators to dampen
inflammation and its sequelae is becoming increasingly promising for treating
medical conditions characterized by significant immunopathology. As shown by the
non-selective S1P receptor modulator FTY720 (fingolimod [Gilenya(®)]) in the
treatment of relapsing-remitting multiple sclerosis (MS), the ability to use
S1P1 modulation to precisely block immune cell traffic-immunomodulation-while
maintaining immunosurveillance, has opened therapeutic opportunities in various
other immune-derived chronic pathologies, including inflammatory bowel disease
(IBD), lupus, psoriasis, as well as, potentially, in early acute viral
respiratory infection. Proof-of-concept studies across validated animal models
with S1P receptor modulators highly selective for S1P1, such as BAF-312
(Siponimod), KRP-203, ONO-4641 (Ceralifimod), ponesimod and RPC-1063, and
emerging clinical trials for safety and efficacy in humans, particularly in MS,
ulcerative colitis (UC) and psoriasis, have set the stage for us to consider
additional testing in various other autoimmune diseases. BACKGROUND: Data from multiple sclerosis (MS) and the MS rodent model,
experimental autoimmune encephalomyelitis (EAE), highlighted an
inflammation-dependent synaptopathy at the basis of the neurodegenerative damage
causing irreversible disability in these disorders. This synaptopathy is
characterized by an imbalance between glutamatergic and GABAergic transmission
and has been proposed to be a potential therapeutic target. Siponimod (BAF312),
a selective sphingosine 1-phosphate1,5 receptor modulator, is currently under
investigation in a clinical trial in secondary progressive MS patients. We
investigated whether siponimod, in addition to its peripheral immune modulation,
may exert direct neuroprotective effects in the central nervous system (CNS) of
mice with chronic progressive EAE.
METHODS: Minipumps allowing continuous intracerebroventricular (icv) infusion of
siponimod for 4 weeks were implanted into C57BL/6 mice subjected to
MOG35-55-induced EAE. Electrophysiology, immunohistochemistry, western blot,
qPCR experiments, and peripheral lymphocyte counts were performed. In addition,
the effect of siponimod on activated microglia was assessed in vitro to confirm
the direct effect of the drug on CNS-resident immune cells.
RESULTS: Siponimod administration (0.45 μg/day) induced a significant beneficial
effect on EAE clinical scores with minimal effect on peripheral lymphocyte
counts. Siponimod rescued defective GABAergic transmission in the striatum of
EAE, without correcting the EAE-induced alterations of glutamatergic
transmission. We observed a significant attenuation of astrogliosis and
microgliosis together with reduced lymphocyte infiltration in the striatum of
EAE mice treated with siponimod. Interestingly, siponimod reduced the release of
IL-6 and RANTES from activated microglial cells in vitro, which might explain
the reduced lymphocyte infiltration. Furthermore, the loss of
parvalbumin-positive (PV+) GABAergic interneurons typical of EAE brains was
rescued by siponimod treatment, providing a plausible explanation of the
selective effects of this drug on inhibitory synaptic transmission.
CONCLUSIONS: Altogether, our results show that siponimod has neuroprotective
effects in the CNS of EAE mice, which are likely independent of its peripheral
immune effect, suggesting that this drug could be effective in limiting
neurodegenerative pathological processes in MS. BACKGROUND: In multiple sclerosis, development of screening tools for
remyelination-promoting molecules is timely.
OBJECTIVE: A Xenopus transgenic line allowing conditional ablation of
myelinating oligodendrocytes has been adapted for in vivo screening of
remyelination-favoring molecules.
METHODS: In this transgenic, the green fluorescent protein reporter is fused to
E. coli nitroreductase and expressed specifically in myelinating
oligodendrocytes. Nitroreductase converts the innocuous pro-drug metronidazole
to a cytotoxin. Spontaneous remyelination occurs after metronidazole-induced
demyelinating responses. As tadpoles are transparent, these events can be
monitored in vivo and quantified. At the end of metronidazole-induced
demyelination, tadpoles were screened in water containing the compounds tested.
After 72 h, remyelination was assayed by counting numbers of oligodendrocytes
per optic nerve.
RESULTS: Among a battery of molecules tested, siponimod, a dual agonist of
sphingosine-1-phosphate receptor 1 and 5, was among the most efficient favoring
remyelination. Crispr/cas9 gene editing showed that the promyelinating effect of
siponimod involves the sphingosine-1-phosphate receptor 5.
CONCLUSION: This Xenopus transgenic line constitutes a simple in vivo screening
platform for myelin repair therapeutics. We validated several known
promyelinating compounds and demonstrated that the strong remyelinating efficacy
of siponimod implicates the sphingosine-1-phosphate receptor 5. Sphingosine 1-phosphate (S1P1 ) modulators provide an emerging therapeutic
approach for various autoimmune disorders such as multiple sclerosis and
psoriasis. Fingolimod is the first approved orally active, selective and potent
drug of this class. Other drugs belonging to this class include siponimod,
ponesimod, ceralifimod, amiselimod, CS-0777 and GSK2018682. However, owing to
the high protein binding, polarity and zwitter-ionic nature of the phosphate
metabolite of parent drugs, it becomes challenging to optimize the extraction
method for this class of compounds. Although, there are individual published
bioanalytical methods for the analysis of selected S1P1 modulators to support
preclinical and clinical drug development, no extensive review compiling all the
bioanalytical methods for the important drugs in the class is available. Thus,
we attempted to prepare a comprehensive review on various bioanalytical methods
for selected S1P1 modulators which will provide all the relevant bioanalytical
information as required by bioanalytical researchers. This review focuses on the
various liquid chromatography with tandem mass spectrometry methods that have
been used to quantify S1P1 modulators in various biological matrices. Extraction
methods included liquid-liquid extraction, solid-phase extraction and one-step
protein precipitation for extracting the analytes. This review captures key
information regarding sample processing options and chromatographic/detection
conditions. Among patients with multiple sclerosis, discontinuing highly effective
disease-modifying treatments can potentially lead to severe disease recurrence,
especially cessation of natalizumab and fingolimod. Similar to fingolimod,
siponimod is a sphingosine-1-phosphate receptor modulator that inhibits the
egress of a lymphocyte subpopulation from lymph nodes. In the present case
report, we describe a patient with MS who experienced substantial disease
exacerbation after withdrawal from siponimod. Siponimod (BAF312) is a synthetic molecule belonging to the
sphingosine-1-phosphate (S1P) modulator family, which has putative
neuroprotective properties and well-characterized immunomodulating effects
mediated by sequestration of B and T cells in secondary lymphoid organs.
Compared to fingolimod (ie, precursor of the S1P modulators commercially
available for the treatment of relapsing-remitting [RR] multiple sclerosis
[MS]), siponimod exhibits selective affinity for types 1 and 5 S1P receptor,
leading to a lower risk of adverse events that are mainly induced by S1P3
receptor activation, such as bradycardia and vasoconstriction. In addition, S1P1
and S1P5 receptors are expressed by neurons and glia and could mediate a
possible neuroprotective effect of the drug. A Phase II clinical trial of
siponimod for RR MS showed a significant effect of the active drug compared to
placebo on reducing gadolinium-enhancing lesions on brain magnetic resoce
imaging (MRI) after 3 months of treatment. In a recently completed Phase III
trial, treatment with siponimod was associated with a significant reduction in
disability progression in secondary progressive (SP) MS patients compared to
placebo. In this article, current evidence supporting siponimod efficacy for SP
MS is reviewed. Traumatic brain injury (TBI) provokes secondary pathological mechanisms,
including ischemic and inflammatory processes. The new research in sphingosine
1-phosphate (S1P) receptor modulators has opened the door for an effective
mechanism of reducing central nervous system (CNS) inflammatory lesion activity.
Thus, the aim of this study was to characterize the immunomodulatory effect of
the functional S1PR1 antagonist, siponimod, in phase III clinical trials for
autoimmune disorders and of the competitive sphingosine 1-phosphate receptor
subtype 1 (S1PR1) antagonist, TASP0277308, in pre-clinical development in an in
vivo model of TBI in mice. We used the well-characterized model of TBI caused by
controlled cortical impact. Mice were injected intraperitoneally with siponimod
or TASP0277308 (1 mg/kg) at 1 and 4 h post-trauma. Our results demonstrated that
these agents exerted significant beneficial effects on TBI pre-clinical scores
in term of anti-inflammatory and immunomodulatory effects, in particular,
attenuation of astrocytes and microglia activation, cytokines release, and
rescue of the reduction of adhesion molecules (i.e., occludin and zonula
occludens-1). Moreover, these compounds were able to decrease T-cell activation
visible by reduction of CD4+ and CD8+, reduce the lesioned area (measured by
2,3,5-triphenyltetrazolium chloride staining), and to preserve tissue
architecture, microtubule stability, and neural plasticity. Moreover, our
findings provide pre-clinical evidence for the use of low-dose oral S1PR1
antagonists as neuroprotective strategies for TBI and broaden our understanding
of the underlying S1PR1-driven neuroinflammatory processes in the
pathophysiology of TBI. Altogether, our results showed that blocking the S1PR1
axis is an effective therapeutic strategy to mitigate neuropathological effects
engaged in the CNS by TBI. Multiple sclerosis treatment faces tremendous changes owing to the approval of
new medications, some of which are available as oral formulations. Until now,
the four orally available medications, fingolimod, dimethylfumarate (BG-12),
teriflunomide, and cladribine have received market authorization, whereas
laquinimod is still under development. Fingolimod is a sphingosine-1-phosphate
inhibitor, which is typically used as escalation therapy and leads to up to 60%
reduction of the annualized relapse rate, but might also have neuroprotective
properties. In addition, there are three more specific S1P agonists in late
stages of development: siponimod, ponesimod, and ozanimod. Dimethylfumarate has
immunomodulatory and cytoprotective functions and is used as baseline therapy.
Teriflunomide, the active metabolite of the rheumatoid arthritis medication
leflunomide, targets the dihydroorotate dehydrogenase, thus inhibiting the
proliferation of lymphocytes by depletion of pyrimidines. Here we will review
the mechanisms of action, clinical trial data, as well as data about safety and
tolerability of the compounds. A high incidence of hemangiosarcoma (HSA) was observed in mice treated for
2 years with siponimod, a sphingosine-1-phosphate receptor 1 (S1P1) functional
antagonist, while no such tumors were observed in rats under the same treatment
conditions. In 3-month rat (90 mg/kg/day) and 9-month mouse (25 and
75 mg/kg/day) in vivo mechanistic studies, vascular endothelial cell (VEC)
activation was observed in both species, but VEC proliferation and persistent
increases in circulating placental growth factor 2 (PLGF2) were only seen in the
mouse. In mice, these effects were sustained over the 9-month study duration,
while in rats increased mitotic gene expression was present at day 3 only and
PLGF2 was induced only during the first week of treatment. In the mouse, the
persistent VEC activation, mitosis induction, and PLGF2 stimulation likely led
to sustained neo-angiogenesis which over life-long treatment may result in HSA
formation. In rats, despite sustained VEC activation, the transient mitotic and
PLGF2 stimuli did not result in the formation of HSA. In vitro, the mouse and
rat primary endothelial cell cultures mirrored their respective in vivo findings
for cell proliferation and PLGF2 release. Human VECs, like rat cells, were
unresponsive to siponimod treatment with no proliferative response and no
release of PLGF2 at all tested concentrations. Hence, it is suggested that the
human cells also reproduce a lack of in vivo response to siponimod. In
conclusion, the molecular mechanisms leading to siponimod-induced HSA in mice
are considered species specific and likely irrelevant to humans. Collaborators: Achiron A, Achtnichts L, Agan K, Akman-Demir G, Allen AB, Antel
JP, Antiguedad AR, Apperson M, Applebee AM, Ayuso GI, Baba M, Bajenaru O, Balasa
R, Balci BP, Barnett M, Bass A, Becker VU, Bejinariu M, Bergh FT, Bergmann A,
Bernitsas E, Berthele A, Bhan V, Bischof F, Bjork RJ, Blevins G, Boehringer M,
Boerner T, Bonek R, Bowen JD, Bowling A, Boyko AN, Boz C, Bracknies V, Braune S,
Brescia Morra V, Brochet B, Brola W, Brownstone PK, Brozman M, Brunet D, Buraga
I, Burnett M, Buttmann M, Butzkueven H, Cahill J, Calkwood JC, Camu W, Cascione
M, Castelnovo G, Centonze D, Cerqueira J, Chan A, Cimprichova A, Cohan S, Comi
G, Conway J, Cooper JA, Corboy J, Correale J, Costell B, Cottrell DA, Coyle PK,
Craner M, Cui L, Cunha L, Czlonkowska A, da Silva AM, de Sa J, de Seze J,
Debouverie M, Debruyne J, Decoo D, Defer G, Derfuss T, Deri NH, Dihenia B,
Dioszeghy P, Donath V, Dubois B, Duddy M, Duquette P, Edan G, Efendi H, Elias S,
Emrich PJ, Estruch BC, Evdoshenko EP, Faiss J, Fedyanin AS, Feneberg W, Fermont
J, Ferdez OF, Ferrer FC, Fink K, Ford H, Ford C, Francia A, Freedman M,
Frishberg B, Galgani S, Garmany GP, Gehring K, Gitt J, Gobbi C, Goldstick LP,
Gonzalez RA, Grandmaison F, Grigoriadis N, Grigorova O, Grimaldi LME, Gross J,
Gross-Paju K, Gudesblatt M, Guillaume D, Haas J, Hancinova V, Hancu A, Hardiman
O, Harmjanz A, Heidenreich FR, Hengstman GJD, Herbert J, Herring M, Hodgkinson
S, Hoffmann OM, Hofmann WE, Honeycutt WD, Hua LH, Huang D, Huang Y, Huang D,
Hupperts R, Imre P, Jacobs AK, Jakab G, Jasinska E, Kaida K, Kalnina J,
Kaprelyan A, Karelis G, Karussis D, Katz A, Khabirov FA, Khatri B, Kimura T,
Kister I, Kizlaitiene R, Klimova E, Koehler J, Komatineni A, Kornhuber A, Kovacs
K, Koves A, Kozubski W, Krastev G, Krupp LB, Kurca E, Lassek C, Laureys G, Lee
L, Lensch E, Leutmezer F, Li H, Linker RA, Linnebank M, Liskova P, Llanera C, Lu
J, Lutterotti A, Lycke J, Macdonell R, Maciejowski M, Maeurer M, Magzhanov RV,
Maida EM, Malciene L, Mao-Draayer Y, Marfia GA, Markowitz C, Mastorodimos V,
Matyas K, Meca-Lallana J, Merino JAG, Mihetiu IG, Milanov I, Miller AE, Millers
A, Mirabella M, Mizuno M, Montalban X, Montoya L, Mori M, Mueller S, Nakahara J,
Nakatsuji Y, Newsome S, Nicholas R, Nielsen AS, Nikfekr E, Nocentini U, Nohara
C, Nomura K, Odinak MM, Olsson T, van Oosten BW, Oreja-Guevara C, Oschmann P,
Overell J, Pachner A, Panczel G, Pandolfo M, Papeix C, Patrucco L, Pelletier J,
Piedrabuena R, Pless M, Polzer U, Pozsegovits K, Rastenyte D, Rauer S,
Reifschneider G, Rey R, Rizvi SA, Robertson D, Rodriguez JM, Rog D, Roshanisefat
H, Rowe V, Rozsa C, Rubin S, Rusek S, Saccà F, Saida T, Salgado AV, Sanchez VEF,
Sanders K, Satori M, Sazonov DV, Scarpini EA, Schlegel E, Schluep M, Schmidt S,
Scholz E, Schrijver HM, Schwab M, Schwartz R, Scott J, Selmaj K, Shafer S,
Sharrack B, Shchukin IA, Shimizu Y, Shotekov P, Siever A, Sigel KO, Silliman S,
Simo M, Simu M, Sinay V, Siquier AE, Siva A, Skoda O, Solomon A, Stangel M,
Stefoski D, Steingo B, Stolyarov ID, Stourac P, Strassburger-Krogias K, Strauss
E, Stuve O, Tarnev I, Tavernarakis A, Tello CR, Terzi M, Ticha V, Ticmeanu M,
Tiel-Wilck K, Toomsoo T, Tubridy N, Tullman MJ, Tumani H, Turcani P, Turner B,
Uccelli A, Urtaza FJO, Vachova M, Valikovics A, Walter S, Van Wijmeersch B,
Vanopdenbosch L, Weber JR, Weiss S, Weissert R, Vermersch P, West T, Wiendl H,
Wiertlewski S, Wildemann B, Willekens B, Visser LH, Vorobeychik G, Xu X,
Yamamura T, Yang YN, Yelamos SM, Yeung M, Zacharias A, Zelkowitz M, Zettl U,
Zhang M, Zhou H, Zieman U, Ziemssen T. PURPOSE OF REVIEW: Multiple sclerosis (MS) is an immune-mediated disorder that
affects the central nervous system (CNS), often first affecting people in early
adulthood. Although most MS patients have a relapsing-remitting course (RRMS) at
disease onset, a substantial proportion later develop chronic progression,
termed secondary progressive MS (SPMS). Approximately 10% of MS patients
experience chronic progression from disease onset, termed primary progressive
multiple sclerosis (PPMS). Although several disease-modifying treatment (DMT)
options exist for relapsing forms of this disease, DMT options are few for
progressive MS (PPMS and SPMS). Herein, we strive to define progressive MS,
review major clinical trials aimed at progressive MS, and delineate potential
strategies in the management of progressive MS.
RECENT FINDINGS: In 2017, the first DMT for PPMS, the B lymphocyte-depleting
monoclonal antibody, ocrelizumab, came to market. Ocrelizumab reduced 12-week
confirmed disability progression (CDP) by 24% versus placebo. Siponimod, a
selective sphingosine-1-phosphate receptor modulator, reduced 3-month CDP by 21%
versus placebo in SPMS. Ibudilast slowed brain atrophy in PPMS and SPMS patients
in a multicenter phase 2b study. Smaller early phase studies of alpha-lipoic
acid and simvastatin each found slowing of rate of whole brain atrophy in SPMS
patients. Reasons now exist for optimism in the search for DMTs for progressive
MS. It remains a challenge to identify outcome measures that accurately reflect
the underlying pathology in progressive MS, which is less inflammatory and more
degenerative than RRMS. Background and Purpose- The contribution of neuroinflammation and, in
particular, the infiltration of the brain by lymphocytes is increasingly
recognized as a substantial pathophysiological mechanism after stroke. The
interaction of lymphocytes with endothelial cells and platelets, termed
thromboinflammation, fosters microvascular dysfunction and secondary infarct
growth. Siponimod is an S1PR (sphingosine-1-phosphate receptor) modulator, which
blocks the egress of lymphocytes from lymphoid organs and has demonstrated
beneficial effects in multiple sclerosis treatment. We investigated the effect
of treatment with siponimod on stroke outcome in a mouse model of cerebral
ischemia. Methods- Transient middle cerebral artery occlusion was induced in
middle-aged wild-type mice. Animals were either treated with siponimod (3 mg/kg;
intraperitoneal) or vehicle for 6 days. Stroke outcome was assessed by magnetic
resoce imaging (spleen volume: prestroke, day 3, and day 7; infarct volume:
days 1, 3, and 7) and behavioral tests (prestroke, day 2, and day 6). Immune
cells of the peripheral blood and brain-infiltrating cells ipsilateral and
contralateral were analyzed by VETScan and by flow cytometry. Results- Siponimod
significantly induced lymphopenia on day 7 after transient middle cerebral
artery occlusion and reduced T-lymphocyte accumulation in the central nervous
system. No effect was detected for lesion size. Conclusions- For siponimod
administered at 3 mg/kg in transient middle cerebral artery occlusion mouse
model, our findings do not provide preclinical evidence for the use of S1PR1/5
modulators as neuroprotectant in stroke therapy. Siponimod (Mayzent®) is an oral selective sphingosine 1-phosphate receptor
subtypes 1 and 5 (S1PR1,5) modulator being developed by Novartis Pharmaceuticals
for the treatment of multiple sclerosis (MS) and intracerebral haemorrhage. In
March 2019, siponimod received its first global approval in the USA, for the
treatment of adults with relapsing forms of MS, including clinically isolated
syndrome, relapsing-remitting disease and active secondary progressive disease.
Siponimod is under regulatory review in the EU and Japan for secondary
progressive MS. This article summarizes the milestone in the development of
siponimod leading to this first global approval for MS in the USA. Introduction: Multiple sclerosis (MS) causes focal lesions of immune-mediated
demyelinating events followed by slow progressive accumulation of disability.
Over the past 2 decades, multiple medications have been studied and approved for
use in MS. Most of these agents work by modulating or suppressing the peripheral
immune system. Siponimod is a newer-generation sphingosine 1 phosphate (S1P)
receptor modulator that internalizes S1P1 receptors, thereby inhibiting efflux
of lymphocytes from lymph nodes and thymus. There are promising data suggesting
that it may also have a direct neuroprotective property independent of
peripheral lymphocytopenia.Areas covered: We reviewed the pharmacology and the
clinical and radiological effects of siponimod.Expert opinion: The selective
effect of siponimod on the S1P1 and S1P5 receptors offers a favorable
side-effect profile and transient bradycardia can be avoided by dose titration.
A phase-II study showed that siponomod has dose-dependent beneficial effects in
patients with relapsing remitting disease. The results of a phase-III study
suggest that siponimod may be beneficial in secondary progressive MS, at least
in patients with disease activity. |
What is a zoonotic virus? | A zoonotic disease is a disease that can be passed from animals to humans. Zoonotic viruses may adapt to a human host eventually becoming endemic in humans, but before doing so punctuated outbreaks of the zoonotic virus may be observed. | Monkeypox virus (MPXV), a close relative of Variola virus, is a zoonotic virus
with an unknown reservoir. Interaction with infected wildlife, bites from
peri-domestic animals, and bushmeat hunting are hypothesized routes of infection
from wildlife to humans. Using a Risk Questionnaire, performed in
monkeypox-affected areas of rural Democratic Republic of the Congo, we describe
the lifestyles and demographics associated with presumptive risk factors for
MPXV infection. We generated two indices to assess risk: Household Materials
Index (HMI), a proxy for socioeconomic status of households and Risk Activity
Index (RAI), which describes presumptive risk for animal-to-human transmission
of MPXV. Based on participant self-reported activity patterns, we found that
people in this population are more likely to visit the forest than a market to
fulfill material needs, and that the reported occupation is limited in
describing behavior of individuals may participate. Being bitten by rodents in
the home was commonly reported, and this was significantly associated with a low
HMI. The highest scoring RAI sub-groups were 'hunters' and males aged ≥ 18
years; however, several activities involving MPXV-implicated animals were
distributed across all sub-groups. The current analysis may be useful in
identifying at-risk groups and help to direct education, outreach and prevention
efforts more efficiently. A zoonotic disease is a disease that can be passed from animals to humans.
Zoonotic viruses may adapt to a human host eventually becoming endemic in
humans, but before doing so punctuated outbreaks of the zoonotic virus may be
observed. The Ebola virus disease (EVD) is an example of such a disease. The
animal population in which the disease agent is able to reproduce in sufficient
number to be able to transmit to a susceptible human host is called a reservoir.
There is little work devoted to understanding stochastic population dynamics in
the presence of a reservoir, specifically the phenomena of disease extinction
and reintroduction. Here, we build a stochastic EVD model and explicitly
consider the impacts of an animal reservoir on the disease persistence. Our
modelling approach enables the analysis of invasion and fade-out dynamics,
including the efficacy of possible intervention strategies. We investigate
outbreak vulnerability and the probability of local extinction and quantify the
effective basic reproduction number. We also consider the effects of dynamic
population size. Our results provide an improved understanding of outbreak and
extinction dynamics in zoonotic diseases, such as EVD. Author information:
(1)Nuffield Department of Medicine, University of Oxford, Oxford OX1 3SY, UK.
[email protected].
(2)Wellcome Trust Major Overseas Programme, Oxford University Clinical Research
Unit, Ho Chi Minh City 700000, Vietnam. [email protected].
(3)Nuffield Department of Medicine, University of Oxford, Oxford OX1 3SY, UK.
[email protected].
(4)Wellcome Trust Major Overseas Programme, Oxford University Clinical Research
Unit, Ho Chi Minh City 700000, Vietnam. [email protected].
(5)Wellcome Trust Major Overseas Programme, Oxford University Clinical Research
Unit, Ho Chi Minh City 700000, Vietnam. [email protected].
(6)Centre for Tropical Medicine and Global Health, Nuffield Department of
Medicine, Oxford University, Oxford OX3 7FZ, UK. [email protected].
(7)Wellcome Trust Major Overseas Programme, Oxford University Clinical Research
Unit, Ho Chi Minh City 700000, Vietnam. [email protected].
(8)Fondation Mérieux, Centre International de Recherche en Infectiologie (CIRI),
69365 Lyon CEDEX 07, France. [email protected].
(9)Wellcome Trust Major Overseas Programme, Oxford University Clinical Research
Unit, Ho Chi Minh City 700000, Vietnam. [email protected].
(10)Centre for Tropical Medicine and Global Health, Nuffield Department of
Medicine, Oxford University, Oxford OX3 7FZ, UK. [email protected].
(11)Wellcome Trust Major Overseas Programme, Oxford University Clinical Research
Unit, Ho Chi Minh City 700000, Vietnam. [email protected].
(12)Centre for Tropical Medicine and Global Health, Nuffield Department of
Medicine, Oxford University, Oxford OX3 7FZ, UK. [email protected].
(13)The London School of Hygiene & Tropical Medicine, London WC1E 7HT, UK.
[email protected].
(14)Centre for Immunity, Infection and Evolution, University of Edinburgh,
Edinburgh EH9 3FL, UK. [email protected].
(15)Nuffield Department of Medicine, University of Oxford, Oxford OX1 3SY, UK.
[email protected]. Rift Valley fever virus (RVFV) is a mosquito-borne, zoonotic virus that infects
rumits, including cattle, sheep, goats, camels, and buffalo. Multiplexing
diagnostic assays that can simultaneously detect antibodies against multiple
RVFV antigens offer a high-throughput test for disease surveillance and vaccine
evaluations. We describe the improvement and evaluation of a previously
developed fluorescence microsphere immunoassay (FMIA) for the detection of IgG
and IgM antibodies against the RVFV glycoprotein (Gn) and the immunogenic
nucleocapsid protein (Np). Well-characterized vaccinated and experimentally
infected rumit sera were used for the evaluation of the assay. Recombit
viral proteins were produced and then coupled to polystyrene magnetic beads for
analysis using the Luminex MAGPIX system with xMAP technology. The FMIA was
performed in parallel with virus neutralization tests. Our results revealed the
highest median fluorescence intensity (MFI) values for the detection of IgG
antibodies against RVFV Np, indicating that this antigen would be a good
candidate for a screening assay. The Np and Gn targets could differentiate
infected animals from animals vaccinated with a candidate subunit vaccine
formulation based on the RVFV Gn and Gc proteins. The results presented in this
report demonstrate that FMIA provides a rapid and robust serological diagnostic
tool for the detection of antibodies against RVFV. The targets developed in this
assay provide the basis for the development of a companion diagnostic test for
an RVFV Gn/Gc subunit vaccine that is capable of differentiating infected from
vaccinated animals (DIVA), as well as a multiplex serodiagnostic assay that can
simultaneously screen for several rumit diseases. Hepatitis E virus (HEV) is a zoonotic virus which circulates in pigs and wild
boars as main reservoir species. To reveal the infection rate in carnivores, we
have carried out a monitoring study of raccoons, raccoon dogs, dogs and cats
sampled in Brandenburg, Germany. In summary, 53.8% (43 of 80) of the raccoons,
34.3% (25 of 73) of the raccoon dogs, 56.6% (47 of 83) of dogs and 32.3% (21 of
65) of cats were tested positive for HEV-specific antibodies. No viral RNA could
be detected. This first description of anti-HEV antibodies in raccoons and
raccoon dogs worldwide and in dogs and cats in Germany highlights the natural
host range expansion of HEV. |
Which drug is the first oral ghrelin receptor inverse agonist to be profiled in healthy subjects? | PF-05190457 is the first oral ghrelin receptor inverse agonist to be profiled in healthy subjects. | |
What is the function of BRD4? | As a member of the bromodomain and extraterminal (BET) family, BRD4 (bromodomain containing 4) can bind to acetylated histones and transcription factors, and is also able to recruit various transcriptional regulators. As transcriptional coactivator, BRD4 represses autophagy and lysosomal function. | The papillomavirus E2 protein is a critical viral regulatory protein with
transcription, DNA replication, and genome maintece functions. We have
previously identified the cellular bromodomain protein Brd4 as a major
E2-interacting protein and established that it participates in tethering bovine
papillomavirus type 1 E2 and viral genomes to host cell mitotic chromosomes. We
have also shown that Brd4 mediates E2-dependent transcriptional activation,
which is strongly inhibited by the disruption of E2/Brd4 binding as well as by
short hairpin RNA (shRNA) knockdown of Brd4 expression levels. Since several
mutants harboring single amino acid substitutions within the E2 transactivation
domain that are defective for both transcriptional transactivation and Brd4
binding are also defective for transcriptional repression, we examined the role
of Brd4 in E2 repression of the human papillomavirus E6/E7 promoter.
Surprisingly, in a variety of in vivo assays, including transcription reporter
assays, HeLa cell proliferation and colony reduction assays, and Northern blot
analyses, neither blocking of the binding of E2 to Brd4 nor shRNA knockdown of
Brd4 affected the E2 repression function. Our study provides evidence for a
Brd4-independent mechanism of E2-mediated repression and suggests that different
cellular factors must be involved in E2-mediated transcriptional activation and
repression functions. NUT midline carcinoma (NMC) belongs to a class of highly lethal and poorly
differentiated epithelial cancers arising mainly in human midline organs. NMC is
caused by the chromosome translocation-mediated fusion of the NUT (nuclear
protein in testis) gene on chromosome 15 to a few other genes, most frequently
the BRD4 gene on chromosome 19. The mechanism by which the BRD4-NUT fusion
product blocks NMC cellular differentiation and contributes to oncogenesis
remains elusive. In this study, we show that BRD4-NUT and BRD4 colocalize in
discrete nuclear foci that are hyperacetylated but transcriptionally inactive.
BRD4-NUT recruits histone acetyltransferases to induce histone hyperacetylation
in these chromatin foci, which provide docking sites for accumulation of
additional BRD4 and associated P-TEFB (positive transcription elongation factor
b) complexes in the transcriptionally inactive BRD4-NUT foci. These molecular
events lead to repression of a BRD4·P-TEFB downstream target gene c-fos, a
component of activator protein 1 (AP-1), that directly regulates epithelial
differentiation. Knockdown of BRD4-NUT in NMC cells disperses the
transcriptionally inactive chromatin foci and releases the transcriptional
activators to stimulate c-fos expression, leading to restoration of cellular
differentiation. Our study provides a novel mechanism by which the BRD4-NUT
oncogene perturbs BRD4 functions to block cellular differentiation and to
contribute to the oncogenic progression in the highly aggressive NMC. Autophagy is a membrane-trafficking process that directs degradation of
cytoplasmic material in lysosomes. The process promotes cellular fidelity, and
while the core machinery of autophagy is known, the mechanisms that promote and
sustain autophagy are less well defined. Here we report that the epigenetic
reader BRD4 and the methyltransferase G9a repress a TFEB/TFE3/MITF-independent
transcriptional program that promotes autophagy and lysosome biogenesis. We show
that BRD4 knockdown induces autophagy in vitro and in vivo in response to some,
but not all, situations. In the case of starvation, a signaling cascade
involving AMPK and histone deacetylase SIRT1 displaces chromatin-bound BRD4,
instigating autophagy gene activation and cell survival. Importantly, this
program is directed independently and also reciprocally to the growth-promoting
properties of BRD4 and is potently repressed by BRD4-NUT, a driver of NUT
midline carcinoma. These findings therefore identify a distinct and selective
mechanism of autophagy regulation. As a member of the bromodomain and extraterminal (BET) family, BRD4 (bromodomain
containing 4) can bind to acetylated histones and transcription factors, and is
also able to recruit various transcriptional regulators. Previous studies have
shown that BRD4 mainly plays a positive role in cell growth and cell cycle
progression. In a recent study conducted by Sakamaki et al., the authors found
that BRD4 acts as a transcriptional repressor in regulating
macroautophagy/autophagy and lysosome gene expression, via binding to the
histone lysine methyltransferase EHMT2/G9a. The oncoprotein BRD4-NUTM1/NUT also
helps block autophagy and lysosome functions. A knockdown of BRD4 allows the
retention of MTOR activity during starvation and significantly undermines
starvation-induced cell death. However, BRD4 repression only contributes to
stimulus-dependent autophagy and aggrephagy, and is not involved in other types
of selective autophagy. Taken together, the newly reported repressive role of
BRD4 in autophagy adds to our understanding of how autophagy and lysosome
functions are regulated at the transcriptional level. Diabetic cardiomyopathy is one of the major complications of diabetes, and due
to the increasing number of patients with diabetes it is a growing concern.
Diabetes‑induced cardiomyopathy has a complex pathogenesis and histone
deacetylase‑mediated epigenetic processes are of prominent importance. The
olfactory bromodomain‑containing protein 4 (BRD4) is a protein that recognizes
and binds acetylated lysine. It has been reported that the high expression of
BRD4 is involved in the process of cardiac hypertrophy. The aim of the present
study was to investigate the function of BRD4 in the process of high glucose
(HG)‑induced cardiac hypertrophy, and to clarify whether epigenetic regulation
involving BRD4 is an important mechanism. It was revealed that BRD4 expression
levels were increased in H9C2 cells following 48 h of HG stimulation. This
result was also observed in a diabetic rat model. Furthermore, HG stimulation
resulted in the upregulation of the myocardial hypertrophy marker, atrial
natriuretic peptide, the cytoskeletal protein α‑actin and fibrosis‑associated
genes including transforming growth factor‑β, SMAD family member 3, connective
tissue growth factor and collagen, type 1, α1. However, administration of the
specific BRD4 inhibitor JQ1 (250 nM) for 48 h reversed this phenomenon.
Furthermore, protein kinase B (AKT) phosphorylation was activated by HG
stimulation and suppressed by JQ1. In conclusion, BRD4 serves an important role
in the pathogenesis of HG‑induced cardiomyocyte hypertrophy through the AKT
pathway. |
What is the protective efficacy of vaxchora against moderate to severe cholera? | The protective efficacy of vaxchora against moderate to severe cholera is 80-100%. | 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 minodixil approved for? | Minoxidil is the only topical drug approved for the treatment of both female and male pattern hair loss. In the US, minoxidil is approved over-the-counter (OTC) at a maximum concentration of 5%. | The National Institutes of Health (US NIH, 2018) estimates that in the US
approximately 50 million men and 30 million women suffer from AGA (also known as
pattern hair loss). Minoxidil is the only topical drug for the treatment of both
female and male pattern hair loss. In the US, minoxidil is approved
over-the-counter (OTC) at a maximum concentration of 5%. In this review, we
summarize the findings of the pivotal studies used in support of the drug's
approval as well as recent discoveries and novel developments in the use of
minoxidil for the treatment of AGA. |
Are Chernobyl survivors at increased risk for breast cancer? | Yes, Chernobyl survivors are at increased risk for breast cancer. | Radiation is a carcinogen, interacting with DNA to produce a range of mutations.
Irradiated cells also show genomic instability, as do adjacent non-irradiated
cells (the bystander effect); the importance to carcinogenesis remains to be
established. Current knowledge of radiation effects is largely dependent on
evidence from exposure to atomic bomb whole body radiation, leading to increases
in a wide range of maligcies. In contrast, millions of people were exposed to
radioactive isotopes in the fallout from the Chernobyl accident, within the
first 20 years there was a large increase in thyroid carcinoma incidence and a
possible radiation-related increase in breast cancer, but as yet there is no
general increase in maligcies. The increase in thyroid carcinoma,
attributable to the very large amounts of iodine 131 released, was first noticed
in children with a strong relationship between young age at exposure and risk of
developing papillary thyroid carcinoma (PTC). The extent of the increase, the
reasons for the relationship to age at exposure, the reduction in attributable
fraction with increasing latency and the role of environmental factors are
discussed. The large number of radiation-induced PTCs has allowed new
observations. The subtype and molecular findings change with latency; most early
cases were solid PTCs with RET-PTC3 rearrangements, later cases were classical
PTCs with RET-PTC1 rearrangements. Small numbers of many other RET
rearrangements have occurred in 'Chernobyl' PTCs, and also rearrangement of
BRAF. Five of the N-terminal genes found in papillary carcinoma rearrangements
are also involved in rearrangements in hematological maligcies; three are
putative tumor suppressor genes, and two are further genes fused to RET in PTCs.
Radiation causes double-strand breaks; the rearrangements common in these
radiation-induced tumors reflect their etiology. It is suggested that oncogenic
rearrangements may commonly involve both a tumor-suppressor gene (or a DNA
repair gene) as well as an oncogene. Involvement of two relevant genes would
give a greater chance of progression and a shorter latency than a single-gene
mutation. More information is needed on germline mutations conferring
susceptibility to radiation-induced PTCs, particularly DNA repair genes. The
radiation exposure to the fallout after Chernobyl was very different from the
whole body radiation after the atomic bombs. The type and molecular pathology of
the thyroid tumors is changing with increasing latency, long latency tumors in
other organs could occur in the future. A comprehensive follow up must continue
for the lifetime of those exposed. Publisher: Shchorichnyy zvit vidobrazhuie osnovni rezul'taty diial'nosti
DerzhavnoI ustanovy „Natsional'nyy naukovyy tsentr radiatsiynoI medytsyny
Natsional'noI akademiI medychnykh nauk UkraIny ” (NNTsRM) z medychnykh problem
Chorno byl's'koI katastrofy, radiatsiynoI medytsyny, radiobiologiI, radiatsiynoI
gigiieny ta epidemiologiI, spivpratsi z VOOZ v merezhi medychnoI gotovnosti ta
dopomogy pry radiatsiynykh avariiakh u 2014 r.Epidemiologichnymy kogortnymy
doslidzhenniamy vstanovleno zrostannia zakhvoriuvanosti (1990–2012 rr.) na rak
shchytopodibnoI zalozy u postrazhdalykh vnaslidok avariI na ChAES (ULNA – u 4,6
raza, evakuyovanykh – u 4,0 ra zy, meshkantsiv zabrudnenykh terytoriy – u 1,3
raza) ta zrostannia chastoty raku molochnoI zalozy u zhinok ULNA 1986–1987 rr.
(u 1994–2012 rr. SIR = 160,0%, 95% DI: 142,4–177,6). Spil'no z Natsional'nym
instytutom raku CShA prodovzheno retrospektyvne doslidzhennia raku
shchytopodibnoI zalozy „vypadok kontrol' ” v kogorti 152 tys. likvidatoriv.
Vstanovleno radiatsiyni ryzyky miielomnoI khvoroby ta khronichnoI limfotsytarnoI
leykemiI.Molekuliarni efekty viddalenogo periodu pislia oprominennia vkliuchaly
zminy ekspresiI geniv TERF1, TERF2, CCND1, dovzhyny telomer, ekspresiI bilka
cyclin D1, gistonu gamma H2AX. Vyznacheno asotsiatsiiu molekuliarnykh zmin z
kognityvnym defitsytom. Vyvcheno genetychni polimorfizmy rs2981582 gena FGFR2,
rs12443621 gena TNRC9, rs3817198 gena LSP1, rs3803662 gena TNRC9 i rs889312 gena
MAP3K1 ta Ikh asotsiatsiiu z rakom molochnoI zalozy; ekspresiiu klitynamy
pukhlyny retseptoriv estrogenu ta progesteronu, antygeniv c kit, tsytokeratynu
5/6, TP53 ta ki67, amplifikatsiynyy status gena Her2/neu, mutatsiynyy status
geniv BRCA1 (mutatsiI 185delAG ta 5382insC) i BRCA2 (mutatsiia 6174delT).
Dovedeno mozhlyvist' persystentsiI radiatsiyno modyfikovanoI prykhovanoI
khromosom noI nestabil'nosti u poslidovnykh generatsiiakh somatychnykh klityn
liudyny.U naselennia vyvcheno stan reproduktyvnoI funktsiI, osoblyvosti
dytiachogo kharchuvannia na radioaktyvno zabrud nenykh terytoriiakh. V ramkakh
vykonia Zagal'noderzhavnoI sotsial'noI programy polipshennia stanu bezpeky,
gigiieny pratsi ta vyrobnychogo seredovyshcha na 2014–2018 roky vpershe v
UkraIni rozrobleno y uspishno vykoo interkalibruvannia dlia 18 laboratoriy
indyvidual'nogo dozymetrychnogo kontroliu. Rozpochato doslidzhennia efektiv
medychnogo oprominennia u interventsiynykh kardiologiv.Eksperymental'ni
doslidzhennia stosuvalysia vplyvu radiomodyfikatoriv na klitynni systemy.V zviti
takozh vidobrazheno rezul'taty naukovo organizatsiynoI, likuval'no
profilaktychnoI roboty, pidgotovky kadriv ta vprovadzhennia.Zvit NNTsRM
zatverdzheno na zasidanni NaukovoI rady NAMN UkraIny 17.03.2015 r. During the past three decades, the deleterious consequences of Chornobyl
accident including carcinogenic effects in the people who were accidentally
exposed to radiation have been intensively studied. In particular, recent
studies provided increased knowledge of the molecular pathogenesis of thyroid
tumors in children exposed to Chornobyl fallout. The risk of several forms of
leukemia including myelodysplastic syndromes is elevated in Chornobyl
liquidators. Furthermore, the upward trends of increases in a variety of other
tumors including breast cancer, cancers of central nervous system and renal
cancer have been reported in the persons exposed to Chornobyl fallout. There is
growing evidence that insufficient apoptosis allows irradiated cells to survive
and thereby contributes to carcinogenesis. The purpose of the present survey is
to summarize the recent findings related to apoptotic biomarkers among cancer
patients from the different populations affected by the Chornobyl catastrophe.
Among the particularly radiosensitive cancer sites, we focused on thyroid cancer
and leukemia. Several genes and/or proteins controlling apoptosis directly or
indirectly have been incorporated into the analysis. The data reviewed here
provide a mechanistic link between the apoptosis alterations and development of
radiation-related cancer in the 30-year post-Chornobyl period. We suggest that
the type of mutations arising from misrepair of DNA double strand breaks (gene
fusion and amplification) is the initial signature event in radiation-induced
thyroid cancer. Much work has to be done over the next years to elucidate
central questions related to the nature of human radiation carcinogenesis. This
article is part of a Special Issue entitled "The Chornobyl Nuclear Accident:
Thirty Years After". BACKGROUND: The study aims to evaluate the current state and tendencies in
multiple primary breast cancer incidence, behavior, and treatment in Ukraine.
METHODS: A total of 2032 patients who received special treatment at the
Department of Breast Tumors and Reconstructive Surgery of the National Cancer
Institute from 2008 to 2015 were included in the study. Among them, there were
195 patients with multiple primary maligt neoplasms: 54.9% patients with
synchronous cancer and 45.1% patients with metachronous cancer. The average age
of patients was 46.6 years, and the percentage of postmenopausal women was
63.1%. Among patients with synchronous cancer, there were 56.1% patients with
only breast localizations and 43.9% with combination of breast and other
localizations, and among patients with metachronous cancer, there were 46.6%
patients with only breast localizations and 53.4% with combination of breast and
other localizations. All the patients were evaluated in terms of aggressiveness
of the disease, survival rates, as well as risk factors and treatment options.
RESULTS: A more aggressive course of breast cancer is observed in patients
exposed to radiation from the Chernobyl accident under the age of 30 years
(P < .01). The clinical course of disease in patients with synchronous cancer is
worse and prognostically unfavorable compared with metachronous cancer
(P < .01). The course of the disease in patients who underwent mastectomy is
worse compared with patients who underwent breast-conserving surgery (P < .01).
Plastic and reconstructive surgery in patients with synchronous cancer was
proven to be reasonable in terms of increase in survival (P < .01).
CONCLUSIONS: The patients with multiple primary breast cancer should have
attentive management and treatment. Multidisciplinary team should concern all
the risk factors and provide the most sufficient option of management. This is
crucial to continue research in this oncological area. This article summarizes the results of 30 y of follow-up of cancer and noncancer
effects in Ukrainian cleanup workers after the Chornobyl accident. The number of
power plant employees and first responders with acute radiation syndrome under
follow-up by the National Research Center for Radiation Medicine decreased from
179 in 1986-1991 to 105 in 2011-2015. Cancers and leukemia (19) and
cardiovascular diseases (21) were the main causes of deaths among acute
radiation syndrome survivors (54) during the postaccident period. Increased
radiation risks of leukemia in the Ukrainian cohort of 110,645 cleanup workers
exposed to low doses are comparable to those among survivors of the atomic bomb
explosions in Japan in 1945. Additionally, an excess of chronic lymphocytic
leukemia was demonstrated in the cleanup workers cohort for 26 y after the
exposure. A significant excess of multiple myeloma incidence [standardized
incidence rate (SIR) 1.61 %, 95% confidence interval (CI) 1.01-2.21], thyroid
cancer (SIR 4.18, 95% CI 3.76-4.59), female breast cancer (SIR 1.57 CI
1.40-1.73), and all cancers combined (SIR 1.07; 95% CI 1.05-1.09) was
registered. High prevalence was demonstrated for cardio- and cerebrovascular
diseases and mental health changes. However, the reasons for the increases
require further investigation. To monitor other possible late effects of
radiation exposure in Chornobyl cleanup workers, analytical cohort and
case-control studies need to include cardiovascular pathology, specifically
types of potentially radiogenic cancers using a molecular epidemiology approach.
Possible effects for further study include increased rates of thyroid, breast,
and lung cancers and multiple myeloma; reduction of radiation risks of leukemia
to population levels; and increased morbidity and mortality of cleanup workers
from cardio- and cerebrovascular pathology. |
What is AZD0530 an inhibitor of? | AZD0530 is a highly selective, dual Src/Abl kinase inhibitor. | Saracatinib, a highly selective, dual Src/Abl kinase inhibitor, is currently in
a Phase II clinical trial for the treatment of ovarian cancer. In our study, we
investigated the effect of saracatinib on the reversal of multidrug resistance
(MDR) induced by ATP-binding cassette (ABC) transporters in vitro and in vivo.
Our results showed that saracatinib significantly enhanced the cytotoxicity of
ABCB1 substrate drugs in ABCB1 overexpressing HeLa/v200, MCF-7/adr and
HEK293/ABCB1 cells, an effect that was stronger than that of gefitinib, whereas
it had no effect on the cytotoxicity of the substrates in ABCC1 overexpressing
HL-60/adr cells and its parental sensitive cells. Additionally, saracatinib
significantly increased the doxorubicin (Dox) and Rho 123 accumulation in
HeLa/v200 and MCF-7/adr cells, whereas it had no effect on HeLa and MCF-7 cells.
Furthermore, saracatinib stimulated the ATPase activity and inhibited
photolabeling of ABCB1 with [(125)I]-iodoarylazidoprazosin in a
concentration-dependent manner. In addition, the homology modeling predicted the
binding conformation of saracatinib within the large hydrophobic drug-binding
cavity of human ABCB1. However, neither the expression level of ABCB1 nor the
phosphorylation level of Akt was altered at the reversal concentrations of
saracatinib. Importantly, saracatinib significantly enhanced the effect of
paclitaxel against ABCB1-overexpressing HeLa/v200 cancer cell xenografts in nude
mice. In conclusion, saracatinib reverses ABCB1-mediated MDR in vitro and in
vivo by directly inhibiting ABCB1 transport function, without altering ABCB1
expression or AKT phosphorylation. These findings may be helpful to attenuate
the effect of MDR by combining saracatinib with other chemotherapeutic drugs in
the clinic. |
Is SATB1 necessary for T-cell maturation? | Special AT-rich sequence binding protein 1 (SATB1) regulates gene expression essential in immune T-cell maturation and switching of fetal globin species, by binding to matrix attachment regions (MARs) of DNA and inducing a local chromatin remodeling. | Special AT-rich binding protein 1 (SATB1) nuclear protein, expressed
predomitly in T cells, regulates genes through targeting chromatin remodeling
during T-cell maturation. Here we show SATB1 family protein induction during
early human adult erythroid progenitor cell differentiation concomitant with
epsilon-globin expression. Erythroid differentiation of human erythroleukemia
K562 cells by hemin simultaneously increases gamma-globin and down-regulates
SATB1 family protein and epsilon-globin gene expression. Chromatin
immunoprecipitation using anti-SATB1 anti-body shows selective binding in vivo
in the beta-globin cluster to the hypersensitive site 2 (HS2) in the locus
control region (LCR) and to the epsilon-globin promoter. SATB1 overexpression
increases epsilon-globin and decreases gamma-globin gene expression accompanied
by histone hyperacetylation and hypomethylation in chromatin from the
epsilon-globin promoter and HS2, and histone hypoacetylation and
hypermethylation associated with the gamma-globin promoter. In K562 cells SATB1
family protein forms a complex with CREB-binding protein (CBP) important in
transcriptional activation. In cotransfection experiments, increase in
epsilon-promoter activity by SATB1 was amplified by CBP and blocked by E1A, a
CBP inhibitor. Our results suggest that SATB1 can up-regulate the epsilon-globin
gene by interaction with specific sites in the beta-globin cluster and imply
that SATB1 family protein expressed in the erythroid progenitor cells may have a
role in globin gene expression during early erythroid differentiation. Special AT-rich sequence binding protein 1 (SATB1) regulates gene expression
essential in immune T-cell maturation and switching of fetal globin species, by
binding to matrix attachment regions (MARs) of DNA and inducing a local
chromatin remodeling. Previously we have revealed a five-helix structure of the
N-terminal CUT domain, which is essentially the folded region in the MAR-binding
domain, of human SATB1 by NMR. Here we determined crystal structure of the
complex of the CUT domain and a MAR DNA, in which the third helix of the CUT
domain deeply enters the major groove of DNA in the B-form. Bases of
5'-CTAATA-3' sequence are contacted by this helix, through direct and
water-mediated hydrogen bonds and apolar and van der Waals contacts. Mutations
at conserved base-contacting residues, Gln402 and Gly403, reduced the
DNA-binding activity, which confirmed the importance of the observed
interactions involving these residues. A significant number of equivalent
contacts are observed also for typically four-helix POU-specific domains of
POU-homologous proteins, indicating that these domains share a common framework
of the DNA-binding mode, recognizing partially similar DNA sequences. |
For how long do Drosophila embryos use maternal genome mRNA? | mitoses before interphase 14 run on maternal products and occur in metasynchronous waves | In Drosophila embryogenesis, mitotic control undergoes a significant transition
during the 14th interphase. Mitoses before interphase 14 run on maternal
products, and occur in metasynchronous waves. Mitoses after interphase 14
require zygotic transcription, and occur asyncronously in an intricate, highly
ordered spatio-temporal pattern. Mutations at the string (stg) locus cause
cell-cycle arrest during this transition, in G2 of interphase 14, yet do not
arrest other aspects of development. This phenotype suggests that stg is
required specifically for initiating mitosis. We describe the cloning of stg,
and show that its predicted amino acid sequence is homologous to that of cdc25,
a regular of mitotic initiation in the yeast S. pombe. In addition, we show that
zygotic expression of stg mRNA occurs in a dynamic series of spatial patterns
which anticipate the patterns of the zygotically driven cell divisions.
Therefore we suggest that regulated expression of stg mRNA controls the timing
and location of these embryonic cell divisions. BACKGROUND: In many animals, the first few hours of life proceed with little or
no transcription, and developmental regulation at these early stages is
dependent on maternal cytoplasm rather than the zygotic nucleus. Translational
control is critical for early Drosophila embryogenesis and is exerted mainly at
the gene level. To understand post-transcriptional regulation during Drosophila
early embryonic development, we used sucrose polysomal gradient analyses and
GeneChip analysis to illustrate the translation profile of individual mRNAs.
RESULTS: We determined ribosomal density and ribosomal occupancy of over 10,000
transcripts during the first ten hours after egg laying.
CONCLUSION: We report the extent and general nature of gene regulation at the
translational level during early Drosophila embryogenesis on a genome-wide
basis. The diversity of the translation profiles indicates multiple mechanisms
modulating transcript-specific translation. Cluster analyses suggest that the
genes involved in some biological processes are co-regulated at the
translational level at certain developmental stages. |
What is the use of erenumab? | Erenumab is a fully human monoclonal antibody calcitonin gene-related peptide (CGRP) receptor antagonist-for the prevention of migraine. CGRP is a vasodilatory neuropeptide implicated in the pathophysiology of migraine and treatment with erenumab was associated with significant reductions in migraine frequency in phase II and III clinical trials. Based on these positive results erenumab was recently approved in the US for the preventive treatment of migraine in adults and has received a positive opinion in the EU for the prophylaxis of migraines in adults who have at least 4 migraine days per month.
Conclusions As a preventive treatment of episodic migraine, erenumab at a dosage of 70 mg monthly significantly reduced migraine frequency and acute migraine-specific medication use. | Monoclonal antibodies (mAbs) targeting calcitonin gene-related peptide (CGRP)
signaling are being explored as prophylactic treatments for migraine. Erenumab
(AMG 334) is the first potent, selective, and competitive human mAb antagonist
of the CGRP receptor. We report the data from two phase I studies assessing the
safety, pharmacokinetics (PK), and pharmacodynamics of single and multiple
administrations of erenumab in healthy subjects and patients with migraine. The
results indicate that the PK profile of erenumab is nonlinear from 1 mg to 70 mg
and the linear portion of the clearance from 70 mg to 210 mg is consistent with
other human immunoglobulin G2 antibodies. Single doses of erenumab resulted in
>75% inhibition of capsaicin-induced dermal blood flow, with no apparent
dose-dependency for erenumab ≥21 mg. Erenumab was generally well tolerated, with
an acceptable safety profile, supporting further clinical development of
erenumab for migraine prevention. BACKGROUND: We tested erenumab, a fully human monoclonal antibody that inhibits
the calcitonin gene-related peptide receptor, for the prevention of episodic
migraine.
METHODS: We randomly assigned patients to receive a subcutaneous injection of
either erenumab, at a dose of 70 mg or 140 mg, or placebo monthly for 6 months.
The primary end point was the change from baseline to months 4 through 6 in the
mean number of migraine days per month. Secondary end points were a 50% or
greater reduction in mean migraine days per month, change in the number of days
of use of acute migraine-specific medication, and change in scores on the
physical-impairment and everyday-activities domains of the Migraine Physical
Function Impact Diary (scale transformed to 0 to 100, with higher scores
representing greater migraine burden on functioning).
RESULTS: A total of 955 patients underwent randomization: 317 were assigned to
the 70-mg erenumab group, 319 to the 140-mg erenumab group, and 319 to the
placebo group. The mean number of migraine days per month at baseline was 8.3 in
the overall population; by months 4 through 6, the number of days was reduced by
3.2 in the 70-mg erenumab group and by 3.7 in the 140-mg erenumab group, as
compared with 1.8 days in the placebo group (P<0.001 for each dose vs. placebo).
A 50% or greater reduction in the mean number of migraine days per month was
achieved for 43.3% of patients in the 70-mg erenumab group and 50.0% of patients
in the 140-mg erenumab group, as compared with 26.6% in the placebo group
(P<0.001 for each dose vs. placebo), and the number of days of use of acute
migraine-specific medication was reduced by 1.1 days in the 70-mg erenumab group
and by 1.6 days in the 140-mg erenumab group, as compared with 0.2 days in the
placebo group (P<0.001 for each dose vs. placebo). Physical-impairment scores
improved by 4.2 and 4.8 points in the 70-mg and 140-mg erenumab groups,
respectively, as compared with 2.4 points in the placebo group (P<0.001 for each
dose vs. placebo), and everyday-activities scores improved by 5.5 and 5.9 points
in the 70-mg and 140-mg erenumab groups, respectively, as compared with 3.3
points in the placebo group (P<0.001 for each dose vs. placebo). The rates of
adverse events were similar between erenumab and placebo.
CONCLUSIONS: Erenumab administered subcutaneously at a monthly dose of 70 mg or
140 mg significantly reduced migraine frequency, the effects of migraines on
daily activities, and the use of acute migraine-specific medication over a
period of 6 months. The long-term safety and durability of the effect of
erenumab require further study. (Funded by Amgen and Novartis; STRIVE
ClinicalTrials.gov number, NCT02456740 .). Migraine is a highly disabling neurological condition, and preventative
treatment still remains problematic, due to aspecificity of the majority of the
currently available prophylactic drugs. Calcitonin-gene-related peptide (CGRP)
plays a crucial role in migraine pathophysiology; agents aimed at blocking its
activity have, therefore, been developed in recent years, among which are
monoclonal antibodies (mAbs) against CGRP, to prevent migraine. Erenumab is the
only mAb that targets the CGRP receptor instead of the ligand, with high
specificity and affinity of binding. This review will report on the most recent
data on erenumab characteristics and on the results of clinical trials on its
employment in the prevention of episodic migraine (4-14 monthly migraine days):
one Phase II and two Phase III trials (completed) and one Phase III trial
(ongoing). Monthly subcutaneous administration (70 mg or 140 mg) of erenumab vs
placebo for 3-6 months showed significantly higher efficacy in reducing the mean
monthly number of migraine days and the use of migraine-specific medication, and
in decreasing physical impairment and impact of migraine on everyday activities
(P<0.001). A favorable safety profile was demonstrated by the lack of
significant differences in the occurrence of adverse events in erenumab-treated
vs placebo-treated patients. Global results so far obtained point to erenumab as
a new promising candidate for the preventative treatment of episodic migraine.
Licence applications for erenumab were recently submitted to the Food and Drug
Administration in the USA and European Medicines Agency in Europe (May/June
2017). Erratum: Calcitonin gene-related peptide receptor as a novel target for the
management of people with episodic migraine: current evidence and safety profile
of erenumab [Corrigendum]. PURPOSE OF REVIEW: Monoclonal antibodies (mAbs) targeting the
calcitonin-gene-related peptide (CGRP) pathway have been developed for episodic
and chronic migraine prevention, either through binding the CGRP ligand
(eptinezumab, fremanezumab, galcanezumab) or the CGRP receptor (erenumab). We
provide an update on published Phase 2 and Phase 3 trials, safety/tolerability
data, pharmacokinetics and mechanism of action of these biologicals.
RECENT FINDINGS: The efficacy data from Phase 2 trials are corroborated by those
from published Phase 3 trials, with a multitude of publications expected in
2018. Review of safety data concluded there was no difference in total adverse
events or main adverse events (including upper respiratory tract infection,
nasopharyngitis, nausea, injection-site pain and back pain) between the mAbs and
placebo injections except apparently for dizziness. The site of action of these
mAbs is not fully elucidated but current insight is that their effect resides in
the periphery; a contribution of central effect(s) can however not be excluded
at present.
SUMMARY: Although efficacy of all four drugs is modest over placebo in episodic
and chronic migraine prevention and overall comparable with available oral
preventive treatments, current tolerability and (short-term) safety data of this
new treatment approach certainly promise a major step forward for migraine
patients. BACKGROUND: Frequent migraine with four or more headache days per month is a
common, disabling neurovascular disease. From a US societal perspective, this
analysis models the clinical efficacy and estimates the value-based price (VBP)
for erenumab, a fully human monoclonal antibody that inhibits the calcitonin
gene-related peptide receptor.
METHODS: A Markov health state transition model was developed to estimate the
incremental costs, quality-adjusted life-years (QALYs), and value-based price
range for erenumab in migraine prevention. The model comprises "on preventive
treatment", "off preventive treatment", and "death" health states across a
10-year time horizon. The evaluation compared erenumab to no preventive
treatment in episodic and chronic migraine patients that have failed at least
one preventive therapy. Therapeutic benefits are based on estimated changes in
monthly migraine days (MMD) from erenumab pivotal clinical trials and a network
meta-analysis of migraine studies. Utilities were estimated using previously
published mapping algorithms. A VBP analysis was performed to identify maximum
erenumab annual prices at willingness-to-pay (WTP) thresholds of
$100,000-$200,000 per QALY. Estimates of VBP under different scenarios such as
choice of different comparators, assumptions around inclusion of placebo effect,
and exclusion of work productivity losses were also generated.
RESULTS: Erenumab resulted in incremental QALYs of 0.185 vs supportive care (SC)
and estimated cost offsets due to reduced MMD of $8,482 over 10 years, with an
average duration of treatment of 2.01 years. The estimated VBP at WTP thresholds
of $100,000-$200,000 for erenumab compared to SC ranged from $14,238-$23,998.
VBP estimates including the placebo effect and excluding work productivity
ranged from $7,445-$13,809; increasing to $12,151-$18,589 with
onabotulinumtoxinA as a comparator in chronic migraine.
CONCLUSION: Erenumab is predicted to reduce migraine-related direct and indirect
costs, and increase QALYs compared to SC. 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. Amgen and Novartis are developing erenumab (AIMOVIG™, erenumab-aooe)-a fully
human monoclonal antibody calcitonin gene-related peptide (CGRP) receptor
antagonist-for the prevention of migraine. CGRP is a vasodilatory neuropeptide
implicated in the pathophysiology of migraine and treatment with erenumab was
associated with significant reductions in migraine frequency in phase II and III
clinical trials. Based on these positive results erenumab was recently approved
in the US for the preventive treatment of migraine in adults and has received a
positive opinion in the EU for the prophylaxis of migraines in adults who have
at least 4 migraine days per month. This article summarizes the milestones in
the development of erenumab leading to this first approval. Migraine is a highly prevalent neurological pain syndrome, and its management is
limited due to side effects posed by current preventive therapies. Calcitonin
gene-related peptide (CGRP) plays a crucial role in the pathogenesis of
migraine. In recent years, research has been dedicated to the development of
monoclonal antibodies against CGRP and CGRP receptors for the treatment of
migraine. This review will focus on the first US FDA-approved CGRP-receptor
monoclonal antibody developed for the prevention of migraine: erenumab. Two
Phase II trials (one for episodic migraine and one for chronic migraine) and two
Phase III trials for episodic migraine have been published demonstrating the
efficacy and safety of erenumab in the prevention of migraine. BACKGROUND: A substantial proportion of patients with migraine does not respond
to, or cannot tolerate, oral preventive treatments. Erenumab is a novel
CGRP-receptor antibody with preventive efficacy in migraine. We assessed its
efficacy and tolerability in patients with episodic migraine in whom previous
treatment with two-to-four migraine preventives had been unsuccessful.
METHODS: LIBERTY was a 12-week, double-blind, placebo-controlled randomised
study at 59 sites in 16 countries. Eligible patients were aged 18-65 years and
had a history of episodic migraine with or without aura for at least 12 months,
had migraine for an average of 4-14 days per month during the 3 months before
screening, and had been treated unsuccessfully (in terms of either efficacy or
tolerability, or both) with between two and four preventive treatments. Eligible
participants were randomly assigned (1:1) to receive either erenumab 140 mg (via
two 70 mg injections) or placebo every 4 weeks subcutaneously for 12 weeks.
Randomisation was by interactive response technology and was stratified by
monthly frequency of migraine headache (4-7 vs 8-14 migraine days per month)
during the baseline phase. Cenduit generated the randomisation list and assigned
participants to groups. Participants, investigators, people doing various
assessments, and the study sponsor were masked to treatment assignment. The
primary endpoint was the proportion of patients achieving a 50% or greater
reduction in the mean number of monthly migraine days during weeks 9-12.
Efficacy was measured in the full analysis set, which included all randomly
assigned patients who started their assigned treatment and completed at least
one post-baseline monthly migraine day measurement. Safety and tolerability were
assessed by recording adverse events and by physical examination, assessment of
vital signs, clinical laboratory assessments, and electrocardiography. Safety
was assessed in all randomly assigned patients who received at least one dose of
study drug. This trial is registered with ClinicalTrials.gov, number
NCT03096834. The trial is closed to new participants, but the open-label
extension phase is ongoing.
FINDINGS: Between March 20, 2017, and Oct 27, 2017, 246 participants were
randomly assigned, 121 to the erenumab group and 125 to the placebo group. 95 of
246 (39%) participants had previously unsuccessfully tried two preventive drugs,
93 (38%) had tried three, and 56 (23%) had tried four. At week 12, 36 (30%)
patients in the erenumab had a 50% or greater reduction from baseline in the
mean number of monthly migraine days, compared with 17 (14%) in the placebo
group (odds ratio 2·7 [95% CI 1·4-5·2]; p=0·002). The tolerability and safety
profiles of erenumab and placebo were similar. The most frequent
treatment-emergent adverse event was injection site pain, which occurred in
seven (6%) participants in both groups.
INTERPRETATION: Compared with placebo, erenumab was efficacious in patients with
episodic migraine who previously did not respond to or tolerate between two and
four previous migraine preventive treatments. Erenumab might be an option for
patients with difficult-to-treat migraine who have high unmet needs and few
treatment options.
FUNDING: Novartis Pharma. Introduction: This paper reviews placebo-controlled randomized double-blind
studies with erenumab for the prevention of migraine. Erenumab is a fully human
monoclonal antibody (mAb), which specifically blocks the calcitonin gene-related
peptide (GGRP) receptor. Areas covered: This manuscript was based on articles
written in English located on PubMed using the following search terms: episodic
and chronic migraine, migraine prophylaxis and prevention, CGRP, CGRP receptor,
CGRP receptor antagonist, erenumab, treatment failures, and trigeminal nerve.
Expert commentary: The primary endpoints in Phase II and III preventive episodic
migraine trials have been reached successfully, and so have multiple secondary
endpoints. Monthly subcutaneous injections of either erenumab 70 mg or 140 mg
reduced mean monthly migraine days (MMDs) after 3 and 6 months significantly
greater than placebo when compared to baseline values with an onset of action
within the first week. About 50% of subjects have at least a 50% reduction of
MMDs. Several patient-reported outcome measures demonstrate improved quality of
life with erenumab. This antibody also shows efficacy in a prior preventive
treatment failure population. The tolerability of erenumab is good, which is
reflected by low dropout rates in all erenumab clinical trials. Within the first
year of treatment, no specific group or type of adverse events were observed. Objective: To review the pharmacology, efficacy, and safety of the calcitonin
gene-related peptide (CGRP) inhibitor erenumab for migraine preventive therapy.
Data Sources: A MEDLINE/PubMed search (January 2000 to January 2019) was
conducted using the keywords erenumab-aooe, erenumab, migraine, migraine
prophylaxis, migraine prevention, and chronic migraine. Additional articles were
identified by hand from references. Study Selection and Data Extraction: We
included English-language articles (excluding poster presentations) evaluating
erenumab pharmacology, efficacy, or safety in humans for migraine prevention.
Data Synthesis: Erenumab is a CGRP inhibitor that inhibits vasodilation in
response to acute migraines, which decreases pain perception during the
migraine. Erenumab efficacy and safety has only been compared with placebo, but
its reduction in monthly migraine days (MMDs) and medication response (≥50%
reduction in MMDs) are comparable to current recommended off-label therapies for
migraine prevention in short-term treatment studies. Additionally, erenumab is
associated with low adverse event burden with no difference found compared with
placebo per published clinical trials. Relevance to Patient Care and Clinical
Practice: Erenumab is the first medication approved in the United States for the
prevention of migraines in adults. No head-to-head data are available, but
existing data suggest that erenumab is at least as effective as current
off-label products and with reduced adverse effects. Conclusion: Erenumab is an
effective once-monthly injectable agent for migraine prevention in patients with
chronic or episodic migraine. It is also effective for patients who have
previously failed migraine preventive therapy. Erenumab has a favorable adverse
effect profile, which may improve patient adherence. BACKGROUND: Erenumab is a human anti-calcitonin gene-related peptide monoclonal
antibody developed for migraine prevention. Migraine predominately affects women
of childbearing age; thus, it is important to determine potential drug-drug
interactions between a common oral contraceptive and drugs used to treat
migraine.
OBJECTIVES: We sought to evaluate potential drug-drug interactions between
erenumab and a common oral contraceptive.
METHODS: Healthy women received three cycles of a norgestimate/ethinyl
estradiol-containing oral contraceptive with a single 140-mg subcutaneous dose
of erenumab during cycle three. Norgestimate metabolites (norgestrel and
norelgestromin) and ethinyl estradiol pharmacokinetics were evaluated in the
absence and presence of erenumab. Primary endpoint was peak plasma concentration
(Cmax) and area under concentration-time curve from time 0 to 24 h (AUCtau).
Luteinizing hormone, follicle-stimulating hormone, and progesterone
concentrations were evaluated as pharmacodynamic markers.
RESULTS: Erenumab did not influence the pharmacokinetics of norelgestromin,
norgestrel, or ethinyl estradiol. Least-squares mean estimates (90% confidence
interval) for Cmax ratios were 1.05 (0.90-1.23), 1.06 (0.97-1.16), and 1.04
(0.88-1.22) for norelgestromin, norgestrel, and ethinyl estradiol, respectively.
Respective AUCtau ratios were 1.02 (0.94-1.12), 1.03 (0.96-1.10), and 1.02
(0.91-1.14). Luteinizing hormone, follicle-stimulating hormone, and progesterone
concentrations were similar after exposure to oral contraceptive alone and with
erenumab.
CONCLUSION: Erenumab did not alter the pharmacokinetics of the active components
of an estrogen/progestin combination oral contraceptive. Thus, no change in
contraceptive efficacy is expected with erenumab.
TRIAL REGISTRATION: ClinicalTrials.gov NCT02792517. BACKGROUND: Migraine is associated with activation of the trigeminovascular
system, release of calcitonin gene-related peptide (CGRP) and dilation of dural
arteries. Novel treatments target calcitonin gene-related peptide or its
receptor, which are present in all vascular beds, raising cardiovascular
concerns. Erenumab is a human CGRP-receptor antibody approved for the
prophylactic treatment of migraine.
METHODS: We characterised the relaxant responses to CGRP in the absence and
presence of erenumab (1 μM) in isolated human middle meningeal, internal mammary
and (proximal and distal) coronary arteries. Furthermore, in human internal
mammary arteries from cardiovascularly-compromised patients, we assessed the
pharmacological specificity of erenumab by investigating whether the
vasodilatory responses to acetylcholine, sodium nitroprusside, pituitary
adenylate cyclase activating polypeptide-38 (PACAP), vasoactive intestinal
peptide and nicardipine, along with the vasoconstrictor responses to
dihydroergotamine, were modified by erenumab.
RESULTS: Calcitonin gene-related peptide induced concentration-dependent
vasodilatory responses in all vessels studied that were significantly
antagonised by erenumab. In human internal mammary arteries from
cardiovascularly-compromised patients, the responses to acetylcholine, sodium
nitroprusside, PACAP, vasoactive intestinal peptide, nicardipine and
dihydroergotamine were unaffected by erenumab.
CONCLUSION: Erenumab inhibits calcitonin gene-related peptide-induced
vasodilatory responses in human middle meningeal arteries, human internal
mammary arteries and human coronary arteries. Moreover, erenumab shows
functional specificity as no interaction was observed with the relaxant
responses to several vasodilators, nor the dihydroergotamine-dependent
vasoconstrictor responses. OBJECTIVE: A phase 2, double-blind, placebo-controlled study to evaluate the
efficacy and safety of erenumab for the prevention of episodic migraine in
Japanese patients was conducted.
BACKGROUND: Previous global clinical studies have demonstrated the efficacy of
erenumab in the prevention of migraine.
METHODS: Patients were randomized to placebo or erenumab 28, 70, or 140 mg
administered subcutaneously once per month for 6 months. The primary endpoint
was change from baseline in mean monthly migraine days over months 4-6 of the
double-blind treatment phase. Secondary endpoints included the proportion of
patients achieving ≥50% reduction from baseline in mean monthly migraine days
(≥50% response) and change from baseline in mean monthly acute migraine-specific
medication treatment days (MSMD) and mean Headache Impact Test (HIT-6™) scores.
Efficacy outcomes were also determined at months 1, 2, and 3.
RESULTS: Four hundred and seventy five patients were randomized 2:1:2:2 to
placebo and erenumab 28, 70, and 140 mg, respectively. Greater reductions in
monthly migraine days were observed for erenumab vs placebo with differences of
-1.25 (95% CI: -2.10 to -0.41; P = .004), -2.31 (95% CI: -3.00 to -1.62;
P < .001), and -1.89 (95% CI: -2.58 to -1.20; P < .001) days for erenumab 28,
70, and 140 mg. The odds of having a ≥50% response were 3.2, 5.6, and 4.7 times
greater for erenumab 28 mg (95% CI: 1.30-7.88; P = .009), 70 mg (95% CI:
2.60-12.06; P < .001), and 140 mg (95% CI: 2.24-9.99; P < .001) than for
placebo. Greater reductions from baseline in mean acute monthly MSMD were
observed for erenumab vs placebo with differences of -1.07 (95% CI: -1.80 to
-0.35; P = .004), -2.07 (95% CI: -2.66 to -1.49; P < .001), and -2.04 (95% CI:
-2.63 to -1.45; P < .001) days for erenumab 28, 70, and 140 mg. Erenumab 70 and
140 mg also resulted in greater improvements in HIT-6™ scores. The safety
profile was similar across treatment groups. The most common adverse event was
nasopharyngitis, which occurred in 29.4% of patients in the placebo group and
28.9%-33.3% of patients in the erenumab groups.
CONCLUSION: Monthly subcutaneous injections of erenumab 70 mg demonstrated
statistically significant and numerically maximal efficacy with a favorable
safety profile, suggesting that erenumab is a potential new therapy for migraine
prevention in Japan. |