41 research outputs found
Recessive mutations in POLR1C cause a leukodystrophy by impairing biogenesis of RNA polymerase III
A small proportion of 4H (Hypomyelination, Hypodontia and Hypogonadotropic Hypogonadism) or RNA polymerase III (POLR3)-related leukodystrophy cases are negative for mutations in the previously identified causative genes POLR3A and POLR3B. Here we report eight of these cases carrying recessive mutations in POLR1C, a gene encoding a shared POLR1 and POLR3 subunit, also mutated in some Treacher Collins syndrome (TCS) cases. Using shotgun proteomics and ChIP sequencing, we demonstrate that leukodystrophy-causative mutations, but not TCS mutations, in POLR1C impair assembly and nuclear import of POLR3, but not POLR1, leading to decreased binding to POLR3 target genes. This study is the first to show that distinct mutations in a gene coding for a shared subunit of two RNA polymerases lead to selective modification of the enzymesâ availability leading to two different clinical conditions and to shed some light on the pathophysiological mechanism of one of the most common hypomyelinating leukodystrophies, POLR3-related leukodystrophy
Characterization of Preoperative, Postsurgical, Acute and Chronic Pain in High Risk Breast Cancer Patients
Funding: The Ketorolac in Breast Cancer trial has been supported by the Anticancer Fund, the Belgian Society of Anaesthesia and Resuscitation, the Fondation Saint-Luc, and the Commission du Patrimoine of the Université catholique de Louvain, Cliniques universitaires Saint-Luc. Acknowledgments: Membership of the KBCt Group, Aline van Maanen, Gauthier Bouche, Alain Dekleermaker, Francois P Duhoux, Marc De Kock, Martine Berliere, Pierre Coulie, Jan Decloedt, Jean-Edouard Guillaume, Marc Ledent, Jean-Pascal Machiels, Véronique Mustin, Walter Swinnen, Lionel Vander Essen, and Jean-Christophe Verougstraete.Peer reviewedPublisher PD
ARMC5 Controls the Degradation of Most Pol II Subunits, and ARMC5 Mutation Increases Neural Tube Defect Risks in Mice and Humans
BACKGROUND: Neural tube defects (NTDs) are caused by genetic and environmental factors. ARMC5 is part of a novel ubiquitin ligase specific for POLR2A, the largest subunit of RNA polymerase II (Pol II).
RESULTS: We find that ARMC5 knockout mice have increased incidence of NTDs, such as spina bifida and exencephaly. Surprisingly, the absence of ARMC5 causes the accumulation of not only POLR2A but also most of the other 11 Pol II subunits, indicating that the degradation of the whole Pol II complex is compromised. The enlarged Pol II pool does not lead to generalized Pol II stalling or a generalized decrease in mRNA transcription. In neural progenitor cells, ARMC5 knockout only dysregulates 106 genes, some of which are known to be involved in neural tube development. FOLH1, critical in folate uptake and hence neural tube development, is downregulated in the knockout intestine. We also identify nine deleterious mutations in the ARMC5 gene in 511 patients with myelomeningocele, a severe form of spina bifida. These mutations impair the interaction between ARMC5 and Pol II and reduce Pol II ubiquitination.
CONCLUSIONS: Mutations in ARMC5 increase the risk of NTDs in mice and humans. ARMC5 is part of an E3 controlling the degradation of all 12 subunits of Pol II under physiological conditions. The Pol II pool size might have effects on NTD pathogenesis, and some of the effects might be via the downregulation of FOLH1. Additional mechanistic work is needed to establish the causal effect of the findings on NTD pathogenesis
ARMC5 Controls the Degradation of Most Pol II Subunits, and ARMC5 Mutation Increases Neural Tube Defect Risks in Mice and Humans
BACKGROUND: Neural tube defects (NTDs) are caused by genetic and environmental factors. ARMC5 is part of a novel ubiquitin ligase specific for POLR2A, the largest subunit of RNA polymerase II (Pol II).
RESULTS: We find that ARMC5 knockout mice have increased incidence of NTDs, such as spina bifida and exencephaly. Surprisingly, the absence of ARMC5 causes the accumulation of not only POLR2A but also most of the other 11 Pol II subunits, indicating that the degradation of the whole Pol II complex is compromised. The enlarged Pol II pool does not lead to generalized Pol II stalling or a generalized decrease in mRNA transcription. In neural progenitor cells, ARMC5 knockout only dysregulates 106 genes, some of which are known to be involved in neural tube development. FOLH1, critical in folate uptake and hence neural tube development, is downregulated in the knockout intestine. We also identify nine deleterious mutations in the ARMC5 gene in 511 patients with myelomeningocele, a severe form of spina bifida. These mutations impair the interaction between ARMC5 and Pol II and reduce Pol II ubiquitination.
CONCLUSIONS: Mutations in ARMC5 increase the risk of NTDs in mice and humans. ARMC5 is part of an E3 controlling the degradation of all 12 subunits of Pol II under physiological conditions. The Pol II pool size might have effects on NTD pathogenesis, and some of the effects might be via the downregulation of FOLH1. Additional mechanistic work is needed to establish the causal effect of the findings on NTD pathogenesis
Characterization of Preoperative, Postsurgical, Acute and Chronic Pain in High Risk Breast Cancer Patients
Background: Pain after breast cancer surgery remains largely unexplained and inconsistently quantified. This study aims to describe the perioperative pain patterns in patients with breast cancer, up to two years after surgery. Methods: This is a pre-planned sub-study of the Ketorolac in Breast Cancer (KBC) trial. The KBC trial was a multicentre, prospective, double-blind, placebo-controlled, randomised trial of a single dose of 30 mg of ketorolac just before breast cancer surgery, aiming to test its effect on recurrences. This sub-study focuses only on pain outcomes. From 2013 to 2015, 203 patients were randomised to ketorolac (n = 96) or placebo (n = 107). Structured questionnaires were delivered by telephone after one and two years, exploring the presence, location, permanence, and frequency of pain. Patientsâ perceptions of pain were captured by an open-ended question, the responses to which were coded and classified using hierarchical clustering. Results: There was no difference in pain between the ketorolac and the placebo group. The reported incidence of permanent pain was 67% and 45% at one and two years, respectively. The largest category was musculoskeletal pain. Permanent pain was mainly described in patients with musculoskeletal pain. The description of pain changed in most patients during the second postoperative year, i.e., moved from one category to another (no pain, permanent, or non-permanent pain, but also, the localisation). This phenomenon includes patients without pain at one year. Conclusions: Pain is a complex phenomenon, but also a fragile and unstable endpoint. Pain after breast cancer surgery does not necessarily mean breast pain but also musculoskeletal and other pains. The permanence of pain and the pain phenotype can change over time
Durvalumab Plus Carboplatin/Paclitaxel Followed by Maintenance Durvalumab With or Without Olaparib as First-Line Treatment for Advanced Endometrial Cancer: The Phase III DUO-E Trial
PURPOSE Immunotherapy and chemotherapy combinations have shown activity in endometrial cancer, with greater benefit in mismatch repair (MMR)-deficient (dMMR) than MMR-proficient (pMMR) disease. Adding a poly(ADP-ribose) polymerase inhibitor may improve outcomes, especially in pMMR disease. METHODS This phase III, global, double-blind, placebo-controlled trial randomly assigned eligible patients with newly diagnosed advanced or recurrent endometrial cancer 1:1:1 to: carboplatin/paclitaxel plus durvalumab placebo followed by placebo maintenance (control arm); carboplatin/paclitaxel plus durvalumab followed by maintenance durvalumab plus olaparib placebo (durvalumab arm); or carboplatin/paclitaxel plus durvalumab followed by maintenance durvalumab plus olaparib (durvalumab + olaparib arm). The primary end points were progression-free survival (PFS) in the durvalumab arm versus control and the durvalumab + olaparib arm versus control. RESULTS Seven hundred eighteen patients were randomly assigned. In the intention-to-treat population, statistically significant PFS benefit was observed in the durvalumab (hazard ratio [HR], 0.71 [95% CI, 0.57 to 0.89]; P = .003) and durvalumab + olaparib arms (HR, 0.55 [95% CI, 0.43 to 0.69]; P < .0001) versus control. Prespecified, exploratory subgroup analyses showed PFS benefit in dMMR (HR [durvalumab v control], 0.42 [95% CI, 0.22 to 0.80]; HR [durvalumab + olaparib v control], 0.41 [95% CI, 0.21 to 0.75]) and pMMR subgroups (HR [durvalumab v control], 0.77 [95% CI, 0.60 to 0.97]; HR [durvalumab + olaparib v control] 0.57; [95% CI, 0.44 to 0.73]); and in PD-L1-positive subgroups (HR [durvalumab v control], 0.63 [95% CI, 0.48 to 0.83]; HR [durvalumab + olaparib v control], 0.42 [95% CI, 0.31 to 0.57]). Interim overall survival results (maturity approximately 28%) were supportive of the primary outcomes (durvalumab v control: HR, 0.77 [95% CI, 0.56 to 1.07]; P = .120; durvalumab + olaparib v control: HR, 0.59 [95% CI, 0.42 to 0.83]; P = .003). The safety profiles of the experimental arms were generally consistent with individual agents. CONCLUSION Carboplatin/paclitaxel plus durvalumab followed by maintenance durvalumab with or without olaparib demonstrated a statistically significant and clinically meaningful PFS benefit in patients with advanced or recurrent endometrial cancer
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Averting biodiversity collapse in tropical forest protected areas
The rapid disruption of tropical forests probably imperils global biodiversity more than any other contemporary phenomenonÂčâ»Âł. With deforestation advancing quickly, protected areas are increasingly becoming final refuges for threatened species and natural ecosystem processes. However, many protected areas in the tropics are themselves vulnerable to human encroachment and other environmental stressesâŽâ»âč. As pressures mount, it is vital to know whether existing reserves can sustain their biodiversity. A critical constraint in addressing this question has been that data describing a broad array of biodiversity groups have been unavailable for a sufficiently large and representative sample of reserves. Here we present a uniquely comprehensive data set on changes over the past 20 to 30 years in 31 functional groups of species and 21 potential drivers of environmental change, for 60 protected areas stratified across the worldâs major tropical regions. Our analysis reveals great variation in reserve âhealthâ: about half of all reserves have been effective or performed passably, but the rest are experiencing an erosion of biodiversity that is often alarmingly widespread taxonomically and functionally. Habitat disruption, hunting and forest-product exploitation were the strongest predictors of declining reserve health. Crucially, environmental changes immediately outside reserves seemed nearly as important as those inside in determining their ecological fate, with changes inside reserves strongly mirroring those occurring around them. These findings suggest that tropical protected areas are often intimately linked ecologically to their surrounding habitats, and that a failure to stem broad-scale loss and degradation of such habitats could sharply increase the likelihood of serious biodiversity declines.Keywords: Ecology, Environmental scienc
Experiences and perspectives of adults on using opioids for pain management in the postoperative period: A scoping review
BACKGROUND Opioids play an important role in peri-operative pain management. However, opioid use is challenging for healthcare practitioners and patients because of concerns related to opioid crises, addiction and side effects.OBJECTIVE This review aimed to identify and synthesise the existing evidence related to adultsâ experiences of opioid use in postoperative pain management.DESIGN Systematic scoping review of qualitative studies. Inductive content analysis and the Theoretical Domains Framework (TDF) were applied to analyse and report the findings and to identify unexplored gaps in the literature.DATA SOURCES Ovid MEDLINE, PsycInfo, Embase, CINAHL (EBSCO), Cochrane Library and Google Scholar.ELIGIBILITY CRITERIA All qualitative and mixed-method studies, in English, that not only used a qualitative approach that explored adultsâ opinions or concerns about opioids and/or opioid reduction, and adultsâ experience related to opioid use for postoperative pain control, including satisfaction, but also aspects of overall quality of a person's life (physical, mental and social well being).RESULTS Ten studies were included; nine were qualitative (n = 9) and one used mixed methods. The studies were primarily conducted in Europe and North America. Concerns about opioid dependence, adverse effects, stigmatisation, gender roles, trust and shared decision-making between clinicians and patients appeared repeatedly throughout the studies. The TDF analysis showed that many peri-operative factors formed people's perceptions and experiences of opioids, driven by the following eight domains: Knowledge, Emotion, Beliefs about consequences, Beliefs about capabilities, Self-confidence, Environmental Context and Resources, Social influences and Decision Processes/Goals. Adults have diverse pain management goals, which can be categorised as proactive and positive goals, such as individualised pain management care, as well as avoidance goals, aimed at sidestepping issues such as addiction and opioid-related side effects.CONCLUSION It is desirable to understand the complexity of adultsâ experiences of pain management especially with opioid use and to support adults in achieving their pain management goals by implementing an individualised approach, effective communication and patientâclinician relationships. However, there is a dearth of studies that examine patientsâ experiences of postoperative opioid use and their involvement in opioid usage decision-making. A summary is provided regarding adultsâ experiences of peri-operative opioid use, which may inform future researchers, healthcare providers and guideline development by considering these factors when improving patient care and experiences
Prostate-Derived Ets Transcription Factor Overexpression is Associated with Nodal Metastasis, Hormone Receptor Positivity in Invasive Breast Cancer
Prostate-derived Ets transcription factor (PDEF) has recently been associated with invasive breast cancer, but no expression profile has been defined in clinical specimens. We undertook a comprehensive PDEF transcriptional expression study of 86 breast cancer clinical specimens, several cell lines, normal tissues. PDEF expression profile was analyzed according to standard clinicopathologic parameters, compared with hormonal receptor, HER-2/neu status, to the expression of the new tumor biomarker Dikkopf-1 (DKK1). Wide ranging PDEF overexpression was observed in 74% of tested tumors, at higher levels than the average expression found in normal breasts. High PDEF expression was associated with hormone receptor positivity (P < .001), moderate to good differentiation (less than grade III, P = .01), dissemination to axillary lymph nodes (P = .002). PDEF was an independent risk factor for nodal involvement (multivariate analysis, odds ratio 1.250, P = .002). It was expressed in a different subgroup compared to DKK1-expressing tumors (P < .001). Our data imply that PDEF mRNA expression could be useful in breast cancer molecular staging. Further insights into PDEF functions at the protein level, possible links with hormone receptors biology, bear great potential for new therapeutic avenues