21 research outputs found
Human aneuploid cells depend on the RAF/MEK/ERK pathway for overcoming increased DNA damage
Aneuploidy is a hallmark of human cancer, yet the molecular mechanisms to cope with aneuploidy-induced cellular stresses remain largely unknown. Here, we induce chromosome mis-segregation in non-transformed RPE1-hTERT cells and derive multiple stable clones with various degrees of aneuploidy. We perform a systematic genomic, transcriptomic and proteomic profiling of 6 isogenic clones, using whole-exome DNA, mRNA and miRNA sequencing, as well as proteomics. Concomitantly, we functionally interrogate their cellular vulnerabilities, using genome-wide CRISPR/Cas9 and large-scale drug screens. Aneuploid clones activate the DNA damage response and are more resistant to further DNA damage induction. Aneuploid cells also exhibit elevated RAF/MEK/ERK pathway activity and are more sensitive to clinically-relevant drugs targeting this pathway, and in particular to CRAF inhibition. Importantly, CRAF and MEK inhibition sensitize aneuploid cells to DNA damage-inducing chemotherapies and to PARP inhibitors. We validate these results in human cancer cell lines. Moreover, resistance of cancer patients to olaparib is associated with high levels of RAF/MEK/ERK signaling, specifically in highly-aneuploid tumors. Overall, our study provides a comprehensive resource for genetically-matched karyotypically-stable cells of various aneuploidy states, and reveals a therapeutically-relevant cellular dependency of aneuploid cells
Impact of COVID-19 on cardiovascular testing in the United States versus the rest of the world
Objectives: This study sought to quantify and compare the decline in volumes of cardiovascular procedures between the United States and non-US institutions during the early phase of the coronavirus disease-2019 (COVID-19) pandemic.
Background: The COVID-19 pandemic has disrupted the care of many non-COVID-19 illnesses. Reductions in diagnostic cardiovascular testing around the world have led to concerns over the implications of reduced testing for cardiovascular disease (CVD) morbidity and mortality.
Methods: Data were submitted to the INCAPS-COVID (International Atomic Energy Agency Non-Invasive Cardiology Protocols Study of COVID-19), a multinational registry comprising 909 institutions in 108 countries (including 155 facilities in 40 U.S. states), assessing the impact of the COVID-19 pandemic on volumes of diagnostic cardiovascular procedures. Data were obtained for April 2020 and compared with volumes of baseline procedures from March 2019. We compared laboratory characteristics, practices, and procedure volumes between U.S. and non-U.S. facilities and between U.S. geographic regions and identified factors associated with volume reduction in the United States.
Results: Reductions in the volumes of procedures in the United States were similar to those in non-U.S. facilities (68% vs. 63%, respectively; p = 0.237), although U.S. facilities reported greater reductions in invasive coronary angiography (69% vs. 53%, respectively; p < 0.001). Significantly more U.S. facilities reported increased use of telehealth and patient screening measures than non-U.S. facilities, such as temperature checks, symptom screenings, and COVID-19 testing. Reductions in volumes of procedures differed between U.S. regions, with larger declines observed in the Northeast (76%) and Midwest (74%) than in the South (62%) and West (44%). Prevalence of COVID-19, staff redeployments, outpatient centers, and urban centers were associated with greater reductions in volume in U.S. facilities in a multivariable analysis.
Conclusions: We observed marked reductions in U.S. cardiovascular testing in the early phase of the pandemic and significant variability between U.S. regions. The association between reductions of volumes and COVID-19 prevalence in the United States highlighted the need for proactive efforts to maintain access to cardiovascular testing in areas most affected by outbreaks of COVID-19 infection
Increased Selectivity toward Cytoplasmic versus Mitochondrial Ribosome Confers Improved Efficiency of Synthetic Aminoglycosides in Fixing Damaged Genes: A Strategy for Treatment of Genetic Diseases Caused by Nonsense Mutations
Compelling evidence is now available that gentamicin
and Geneticin
(G418) can induce the mammalian ribosome to suppress disease-causing
nonsense mutations and partially restore the expression of functional
proteins. However, toxicity and relative lack of efficacy at subtoxic
doses limit the use of gentamicin for suppression therapy. Although
G418 exhibits the strongest activity, it is very cytotoxic even at
low doses. We describe here the first systematic development of the
novel aminoglycoside (<i>S</i>)-<b>11</b> exhibiting
similar <i>in vitro</i> and <i>ex vivo</i> activity
to that of G418, while its cell toxicity is significantly lower than
those of gentamicin and G418. Using a series of biochemical assays,
we provide proof of principle that antibacterial activity and toxicity
of aminoglycosides can be dissected from their suppression activity.
The data further indicate that the increased specificity toward cytoplasmic
ribosome correlates with the increased activity and that the decreased
specificity toward mitochondrial ribosome confers the lowered cytotoxicity
Peer Review in a General Medical Research Journal Before and During the COVID-19 Pandemic
IMPORTANCE: Although peer review is an important component of publication for new research, the viability of this process has been questioned, particularly with the added stressors of the COVID-19 pandemic. OBJECTIVE: To characterize rates of peer reviewer acceptance of invitations to review manuscripts, reviewer turnaround times, and editor-assessed quality of reviews before and after the start of the COVID-19 pandemic at a large, open-access general medical journal. DESIGN, SETTING, AND PARTICIPANTS: This retrospective, pre-post cohort study examined all research manuscripts submitted to JAMA Network Open between January 1, 2019, and June 29, 2021, either directly or via transfer from other JAMA Network journals, for which at least 1 peer review of manuscript content was solicited. Measures were compared between the period before the World Health Organization declaration of a COVID-19 pandemic on March 11, 2020 (14.3 months), and the period during the pandemic (15.6 months) among all reviewed manuscripts and between pandemic-period manuscripts that did or did not address COVID-19. MAIN OUTCOMES AND MEASURES: For each reviewed manuscript, the number of invitations sent to reviewers, proportions of reviewers accepting invitations, time in days to return reviews, and editor-assessed quality ratings of reviews were determined. RESULTS: In total, the journal sought review for 5013 manuscripts, including 4295 Original Investigations (85.7%) and 718 Research Letters (14.3%); 1860 manuscripts were submitted during the prepandemic period and 3153 during the pandemic period. Comparing the prepandemic with the pandemic period, the mean (SD) number of reviews rated as high quality (very good or excellent) per manuscript increased slightly from 1.3 (0.7) to 1.5 (0.7) (P \u3c .001), and the mean (SD) time for reviewers to return reviews was modestly shorter (from 15.8 [7.6] days to 14.4 [7.0] days; P \u3c .001), a difference that persisted in linear regression models accounting for manuscript type, study design, and whether the manuscript addressed COVID-19. CONCLUSIONS AND RELEVANCE: In this cohort study, the speed and editor-reported quality of peer reviews in an open-access general medical journal improved modestly during the initial year of the pandemic. Additional study will be necessary to understand how the pandemic has affected reviewer burden and fatigue
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Polygenic Inheritance of Paclitaxel-Induced Sensory Peripheral Neuropathy Driven by Axon Outgrowth Gene Sets in CALGB 40101 (Alliance)
Peripheral neuropathy is a common dose-limiting toxicity for patients treated with paclitaxel. For most individuals there are no known risk factors that predispose patients to the adverse event, and pathogenesis for paclitaxel-induced peripheral neuropathy is unknown. Determining whether there is a heritable component to paclitaxel induced peripheral neuropathy would be valuable in guiding clinical decisions and may provide insight into treatment of and mechanisms for the toxicity. Using genotype and patient information from the paclitaxel arm of CALGB 40101 (Alliance), a phase III clinical trial evaluating adjuvant therapies for breast cancer in women, we estimated the variance in maximum grade and dose at first instance of sensory peripheral neuropathy. Our results suggest that paclitaxel-induced neuropathy has a heritable component, driven in part by genes involved in axon outgrowth. Disruption of axon outgrowth may be one of the mechanisms by which paclitaxel treatment results in sensory peripheral neuropathy in susceptible patients
Process of drug registration in Israel: the correlation between the number of discussions within the Ministry of Health and postapproval variations by EMA and/or FDA
Objectives US FDA and EMA allow facilitated regulatory pathways to expedite access to new treatments. Limited supportive data may result in major postapproval variations. In Israel, partly relying on Food and Drug Administration (FDA) and European Medicines Agency (EMA), clinical data are reviewed independently by the Advisory Committee of Drug Registration (ACDR). In this study, the correlation between the number of discussions at the ACDR and major postapproval variations is examined.Design This is an observational retrospective comparative cohort study.Setting Applications with FDA and/or EMA approval at time of assessment in Israel were included. The timeframe was chosen to allow a minimum of 3 years of postmarketing approval experience for potential major label variations. Data regarding the number of discussions at ACDR were extracted from protocols. Data on postapproval major variations were extracted from the FDA and EMA websites.Results Between 2014 and 2016, 226 (176 drugs) applications, met the study criteria. 198 (87.6%) and 28 (12.4%) were approved following single and multiple discussions, respectively. A major postapproval variation was recorded in 129 (65.2%) compared with 23 (82.1%) applications approved following single and multiple discussions, respectively (p=0.002). Increased risk for major variation was found for medicines approved following multiple discussions (HR=1.98, 95% CI: 1.26 to 3.09) with a median time of 1.2 years, applications approved based on phase II trials (HR=2.58, 95% CI: 1.72 to 3.87), surrogate endpoints (HR=1.99, 95% CI: 1.44 to 2.74) and oncologic indications (HR=2.48, 95% CI: 1.78 to 3.45).Conclusions Multiple ACDR discussions associated with limited supportive data are predictive for major postapproval variations. Moreover, our findings demonstrate that approval by the FDA and/or EMA does not pave the way to automatic approval in Israel. In a substantial per cent of the cases, submission of the same clinical data resulted in different safety and efficacy considerations, requiring additional supporting data in some cases or even rejection of the application in others