Defective sister chromatid cohesion is synthetically lethal with impaired APC/C function

Warsaw breakage syndrome (WABS) is caused by defective DDX11, a DNA helicase that is essential for chromatid cohesion. Here, a paired genome-wide siRNA screen in patient-derived cell lines reveals that WABS cells do not tolerate partial depletion of individual APC/C subunits or the spindle checkpoint inhibitor p31comet. A combination of reduced cohesion and impaired APC/C function also leads to fatal mitotic arrest in diploid RPE1 cells. Moreover, WABS cell lines, and several cancer cell lines with cohesion defects, display a highly increased response to a new cell-permeable APC/C inhibitor, apcin, but not to the spindle poison paclitaxel. Synthetic lethality of APC/C inhibition and cohesion defects strictly depends on a functional mitotic spindle checkpoint as well as on intact microtubule pulling forces. This indicates that the underlying mechanism involves cohesion fatigue in response to mitotic delay, leading to spindle checkpoint re-activation and lethal mitotic arrest. Our results point to APC/C inhibitors as promising therapeutic agents targeting cohesion-defective cancers

A powerful global test for spliceQTL effects

Statistical methods to test for effects of SNPs on exon inclusion exist, but often rely on testing of associations between multiple exon-SNP pairs, with sometimes subsequent summarization of results at the gene level. Such approaches require heavy multiple testing correction, and detect mostly events with large effect sizes. We propose here a test to find spliceQTL effects which takes all exons and all SNPs into account simultaneously. For any chosen gene, this score-based test looks for association between the set of exon expressions and the set of SNPs, via a random-effects model framework. It is efficient to compute, and can be used if the number of SNPs is larger than the number of samples. In addition, the test is powerful to detect effects that are relatively small for individual exon-SNP pairs, but are observed for many pairs. Furthermore, test results are more often replicated across datasets than pairwise testing results. This partly our test is more robust to exon-SNP pair-specific effects, but do not extend to multiple pairs within the same gene. We conclude that the test we propose here offers more power and better replicability in the search for spliceQTL effects

Improvement of menopausal symptoms and the impact on work ability: A retrospective cohort pilot study

Objective: In this study we aimed to pilot test the hypothesis that in women who are severely bothered by their menopausal complaints, improvement of menopausal symptoms is associated with an improvement in self-perceived work ability. Study design: This retrospective cohort study assessed the work ability of first-time attendees (n = 31) of a menopause clinic at baseline (T0) and 3–9 months follow-up (T1). All patients received care as usual according to local protocol, no interventions were applied by the researchers. Self-reported questionnaire data assessing work ability (Work Ability Index; WAI) and menopausal symptoms (Greene Climacteric Scale; GCS) were used. Main outcome measures: Multiple linear regression was used in an exploratory analysis to examine the relationship between change in WAI score (ΔWAI) and change in menopausal symptoms (ΔGCS), after adjustment for potential confounders. Additional exploratory univariate linear regression analyses were performed to assess the associations of change in WAI score with change in the different GCS domains and with type of treatment. Results: Twenty-seven out of 31 women reported improvement in work ability at follow-up (T1) (M = 30.73, SD = 6.42 respectively, M = 34.86, SD = 5.98). All women reported to be less bothered by their menopausal symptoms at T1 (M = 26.57, SD = 8.69 respectively, M = 14.73, SD = 6.36). Multivariate linear regression demonstrated a significant association between the WAI and GCS change scores after correction for confounders (beta ΔGCS = 0.283, p = 0.014). After additional adjustment for WAI at baseline, this association was no longer significant (beta ΔGCS = 0.172, p = 0.164). Change in GCS depression domain (ΔGCS depression) was significantly associated with ΔWAI, although after correction for WAI at baseline the effect of ΔGCS depression was no longer significant (beta = 0.855, p = 0.113). The WAI and GCS change scores were highly correlated, as a result their coefficients were not statistically significant separately. Conclusions: Treatment aimed at alleviating menopausal symptoms in symptomatic women could lead to improvement of menopausal symptoms along with improvement in work ability. Improvement of depressive symptoms seem particularly important for this outcome

A functional siRNA screen identifies RhoGTPase-associated genes involved in thrombin-induced endothelial permeability.

Thrombin and other inflammatory mediators may induce vascular permeability through the disruption of adherens junctions between adjacent endothelial cells. If uncontrolled, hyperpermeability leads to an impaired barrier, fluid leakage and edema, which can contribute to multi-organ failure and death. RhoGTPases control cytoskeletal dynamics, adhesion and migration and are known regulators of endothelial integrity. Knowledge of the precise role of each RhoGTPase, and their associated regulatory and effector genes, in endothelial integrity is incomplete. Using a combination of a RNAi screen with electrical impedance measurements, we quantified the effect of individually silencing 270 Rho-associated genes on the barrier function of thrombin-activated, primary endothelial cells. Known and novel RhoGTPase-associated regulators that modulate the response to thrombin were identified (RTKN, TIAM2, MLC1, ARPC1B, SEPT2, SLC9A3R1, RACGAP1, RAPGEF2, RHOD, PREX1, ARHGEF7, PLXNB2, ARHGAP45, SRGAP2, ARHGEF5). In conclusion, with this siRNA screen, we confirmed the roles of known regulators of endothelial integrity but also identified new, potential key players in thrombin-induced endothelial signaling

Testing for coeliac disease rarely leads to a diagnosis: a population-based study

Background Coeliac disease (CD) has an estimated prevalence of ∼1% in Europe with a significant gap between undiagnosed and diagnosed CD. Active case finding may help to bridge this gap yet the diagnostic yield of such active case finding in general practice by serological testing is unknown. Objective The aim of this study was to determine (1) the frequency of diagnosed CD in the general population, and (2) to investigate the yield of active case finding by general practitioners. Methods Electronic medical records of 207.200 patients registered in 49 general practices in The Netherlands in 2016 were analysed. An extensive search strategy, based on International Classification of Primary Care codes, free text and diagnostic test codes was performed to search CD- or gluten-related contacts. Results The incidence of CD diagnosis in general practice in 2016 was 0.01%. The prevalence of diagnosed CD reported in the general practice in the Netherlands was 0.19%, and considerably higher than previously reported in the general population. During the one year course of the study 0.95% of the population had a gluten-related contact with their GP; most of them (72%) were prompted by gastrointestinal complaints. Serological testing was performed in 66% (n = 1296) of these patients and positive in only 1.6% (n = 21). Conclusion The number of diagnosed CD patients in the Netherlands is substantially higher than previously reported. This suggests that the gap between diagnosed and undiagnosed patients is lower than generally assumed. This may explain that despite a high frequency of gluten-related consultations in general practice the diagnostic yield of case finding by serological testing is low.Key points The diagnostic approach of GPs regarding CD and the diagnostic yield is largely unknown Case finding in a primary health care practice has a low yield of 1.6% CD testing was mostly prompted by consultation for gastrointestinal symptoms There is a heterogeneity in types of serological test performed in primary car

Expression of Oncolytic Adenovirus-Encoded RNAi Molecules Is Most Effective in a pri-miRNA Precursor Format

Oncolytic adenoviruses are being developed as new anti-cancer agents. Their efficacy can be improved by incorporating RNA interference (RNAi) molecules. RNAi molecules can be expressed in various precursor formats. The aim of this study was to determine the most effective format. To this end, we constructed three Δ24-type oncolytic adenoviruses, with human microRNA-1 (miR-1) expression cassettes in short hairpin RNA (shRNA), precursor microRNA (pre-miRNA), and primary miRNA (pri-miRNA) format, respectively. The viruses were compared for virus replication, mature miR-1 expression, and target gene silencing in cancer cells. Incorporation of the cassettes had only minor effects on virus replication. Mature miR-1 expression from the pri-miRNA format reached on average 100-fold higher levels than from the other two formats. This expression remained stable upon long-term virus propagation. Infection with the pri-miR-1-expressing virus silenced the validated miR-1 targets FOXP1 and MET. Drosha knockout almost completely abrogated mature miR-1 expression, confirming that processing of adenovirus-encoded pri-miR-1 was dependent on the host cell miRNA machinery. Using simple in vitro recombination cloning, a similar virus expressing miR-26b was made and shown to silence the validated miR-26b target PTGS2. We thus provide a platform for construction of oncolytic adenoviruses with high expression of RNAi molecules of choice

Oncogenic Role of miR-15a-3p in 13q Amplicon-Driven Colorectal Adenoma-to-Carcinoma Progression.

Progression from colorectal adenoma to carcinoma is strongly associated with an accumulation of genomic alterations, including gain of chromosome 13. This gain affects the whole q arm and is present in 40%-60% of all colorectal cancers (CRCs). Several genes located at this amplicon are known to be overexpressed in carcinomas due to copy number dosage. A subset of these genes, including the mir-17~92 cluster, are functionally involved in CRC development. The present study set out to explore whether apart from mir-17~92, other miRNAs located at the 13q amplicon show a copy number dependent dosage effect that may contribute to 13q-driven colorectal adenoma-to-carcinoma progression. Integration of publically available miRNA expression, target mRNA expression and DNA copy number data from 125 CRCs yielded three miRNAs, miR-15a, -17, and -20a, of which high expression levels were significantly correlated with a 13q gain and which influenced target mRNA expression. These results could be confirmed by qRT-PCR in a series of 100 colon adenomas and carcinomas.Functional analysis of both mature miRNAs encoded by mir-15a, i.e. miR-15a-5p and miR-15a-3p, showed that silencing of miR-15a-3p significantly inhibited viability of CRC cells. Integration of miR-15a expression levels with mRNA expression data of predicted target genes identified mitochondrial uncoupling protein 2 (UCP2) and COP9 signalosome subunit 2 (COPS2) as candidates with significantly decreased expression in CRCs with 13q gain. Upon silencing of miR-15a-3p, mRNA expression of both genes increased in CRC cells, supporting miR-15a-3p mediated regulation of UPC2 and COPS2 expression. In conclusion, significant overexpression of miR-15a-3p due to gain of 13q is functionally relevant in CRC, with UCP2 and COPS2 as candidate target genes. Taken together our findings suggest that miR-15a-3p may contribute to adenoma-to-carcinoma progression