Citations

Abstract BRCA2 mutations contribute to the pathogenesis and treatment sensitivity of a subset of ovarian, breast, prostate, and pancreatic cancers. When these cancers become therapy resistant, secondary mutations that restore the BRCA2 open reading frame are found in half the cases, but other causes of resistance remain incompletely understood. Here, we identified translational readthrough of a premature termination codon (PTC) as a cause of resistance to poly(ADP-ribose) polymerase inhibitors (PARPis) and cisplatin in cells derived from the BRCA2-mutated ovarian cancer line PEO1 by PARPi selection. Despite persistence of the signature 4965C > G (p.Y1655X) BRCA2 mutation, low-level expression of full-length BRCA2 protein was detectable in these cells by immunoblotting and tandem mass spectrometry. Either BRCA2 knockdown or gene interruption 5′ or 3′ to the PTC restored treatment sensitivity, implicating BRCA2 in the resistance. Reporter assays demonstrated UAG-selective readthrough in the resistant clones but not parental cells. Moreover, custom searching of global proteomic data indicated readthrough of stop codons, particularly UAGs, in additional proteins in the resistant clones. Finally, multi-omic analysis identified multiple changes in the nonsense-mediated decay and termination machineries that favor readthrough. Accordingly, the present results identify PTC readthrough as a potential mechanism of drug resistance in cells with BRCA2 nonsense mutations.

BACKGROUND: People with narcolepsy are at increased risk for hypertension and cardiovascular disease; excessive sodium intake is linked to both. METHODS: We studied patients with narcolepsy and office systolic blood pressures (BPs) of 130 to 155 mm Hg taking twice-nightly high-sodium oxybate for ≥6 weeks who switched to low-sodium oxybate at the same dosage. The primary end point was the change from baseline in mean 24-hour ambulatory systolic BP at the end of treatment (≈6 weeks after switching). Secondary and exploratory end points included changes in diastolic BP, office BP, and 24-hour sodium excretion. RESULTS: Patients (n=43) had a mean age of 45 years, were 65% female, 33% on antihypertensives, with baseline mean (SD) office BP of 138.0/85.2 (5.7/6.6). Mean (SD) total high- and low-sodium oxybate dosages of 8.0 (1.1) and 8.1 (1.1) g/night, respectively, represented 1456.5 (206.2) and 117.8 (16.3) mg of sodium. The median 24-hour urinary sodium was 4278 mg/d at baseline and 2703 mg/d at the end of treatment (median change, 1288 mg/d). Mean (SE) 24-hour ambulatory systolic BPs at baseline and study end were 132.3 (1.8) and 128.2 (1.8) mm Hg (least-squares mean change, −4.1 [95% CI, −6.9 to −1.4] mm Hg; 1-sided P =0.0019). BP changes by narcolepsy subtype, sex, body mass index, baseline office BP, and baseline antihypertensive use were consistent with the overall effect size. CONCLUSIONS: People with narcolepsy switching from high- to low-sodium oxybate showed substantially reduced daily medication-related sodium intake and significant 24-hour BP reductions. These results demonstrate the importance of reducing pharmaceutical sodium content in this elevated cardiovascular risk patient population. REGISTRATION: URL: https://www.clinicaltrials.gov ; Unique identifier: NCT05869773.

Abstract Background Lung adenocarcinoma in never-smokers is a major public health burden, especially among East Asian women. Polygenic risk scores (PRSs) are promising for risk stratification but are primarily developed in European-ancestry populations. We aimed to develop and validate single- and multi-ancestry PRSs for East Asian never-smokers to improve lung adenocarcinoma risk prediction. Methods PRSs were developed using genome-wide association study summary statistics from East Asian (8002 cases; 20 782 controls) and European (2058 cases; 5575 controls) populations. Single-ancestry models included a PRS with 25 single nucleotide variants (PRS-25), PRS clumping and thresholding (CT), and LDpred2; multi-ancestry models included LDpred2 plus European PRS-128, PRS-CSx, and clumping and thresholding, super learning, empirical Bayes (CT-SLEB). Performance was evaluated in independent East Asian data from the Female Lung Cancer Consortium and externally validated in the Nanjing Lung Cancer Cohort. We assessed predictive accuracy via area under the curve operating procedure (AUC), with 10-year and (ages 30-80 years) absolute risks estimates. Results The best multi-ancestry PRS, using East Asian and European data via CT-SLEB, outperformed the best East Asian-only (LDpred2; AUC = 0.629, 95% confidence interval [CI] = 0.618 to 0.641), achieving an AUC of 0.640 (95% CI = 0.629 to 0.653) and odds ratio of 1.71 (95% CI = 1.61 to 1.82) per standard deviation increase. Nanjing Lung Cancer Cohort validation confirmed robust performance (AUC = 0.649, 95% CI = 0.623 to 0.676). The top 20% PRS group had a 3.92-fold higher lung adenocarcinoma risk than the bottom 20%. Further, the top 5% PRS group reached a 6.69% lifetime absolute risk. Notably, this group reached the average population 10-year lung adenocarcinoma risk at age 50 years (0.42%) by age 41 years, 9 years earlier. Conclusions Multi-ancestry PRS approaches enhance lung adenocarcinoma risk stratification in East Asian never-smokers, with consistent external validation, suggesting future clinical utility.

Background Dementia with Lewy bodies (DLB) is a common degenerative dementia, but no studies investigate bereaved caregiver experiences. Objective To investigate the experiences of caregivers three months after the death of persons with DLB using a mixed-methods approach. Methods Dyads of individuals with moderate-advanced DLB and their primary informal caregivers were followed prospectively every 6 months until the person with DLB died. Caregivers completed a study visit with questionnaires and a semi-structured interview ∼3 months later. Spearman correlation coefficients and Wilcoxon rank-sum tests evaluated the relationships of post-death measures with pre-death patient and caregiver variables. Thematic analysis was used to analyze the interviews. Results Seventy-three caregivers completed visits (mean 3.5 months post-death). Most of the caregivers were women (82.2%) and spouses (76.7%) or adult children (17.8%). Over 40% had scores indicating risk for clinical depression. Post-death caregiver experiences (depression, quality of life, grief, resilience) correlated with pre-death caregiver experiences. Post-death experiences did not associate with patient characteristics, disease-related symptoms, or healthcare services used in the last 6 months of life. Trajectories for caregiver measures from pre- to post-death visits varied widely. Interview themes included grief and sadness, anger, guilt and regret, relief, appreciation/gratitude, and adjusting to a new normal. Conclusions The finding that pre-death caregiving experiences have the strongest association with post-death experiences emphasizes the critical importance of accessible and evidence-based caregiver support before and after the death of a person with DLB. Research is needed to develop interventions for current and bereaved caregivers of individuals with DLB. Trial registration information NCT04829656 (submitted 2021-03-22).

Background: Current understanding of associations between alcohol use and falls among people with HIV (PWH) is limited due to few and inconsistent studies. Given the prevalence of heavy episodic alcohol use reported among PWH, this remains an important question. Methods: Alcohol use was measured using the Alcohol Use Disorders Identification Test-Consumption (AUDIT-C) and self-reported alcohol use treatment and/or diagnosis of alcohol use disorder (collectively AUD) among PWH at eight CFAR Network of Integrated Clinical Systems (CNICS) sites from 2021 to 2024. Falls were self-reported using the components of the Falls Risk for Older People in the Community (FROP-Com) questionnaire. Cross-sectional associations between alcohol use and falls were examined using relative risk models adjusted for age, sex, race/ethnicity, and geographic location. Results: Among 5729 PWH, mean age was 55 years; 42% reported White and 41% reported Black/African American race/ethnicity; and 81% were male. Mean AUDIT-C score was 1.9 (range: 0–12); 27% reported heavy episodic drinking; 22% had AUD; and 22% reported falling in the past year. Reporting at least one fall in the past year was not associated with any measure of current alcohol use. AUD was associated with reporting at least one fall [prevalence ratio = 1.54; 95% confidence interval (CI) 1.39–1.70] and number of falls [one fall: prevalence ratio = 1.27 (95% CI: 1.08–1.50); at least two falls: prevalence ratio = 1.84 (95% CI: 1.58–2.15)]. Conclusion: Among PWH, 22% reported falling, which was associated with AUD, but not current alcohol use, suggesting that a mechanism other than acute intoxication could be responsible. Further longitudinal research is warranted to explore mechanisms for why AUD, but not current alcohol use, is associated with falls.

Abstract Aims Although cardiovascular disease (CVD) screening and preventive care in the early postpartum are recommended for women with prior gestational diabetes (GDM) and hypertensive disorders of pregnancy (HDP), certain barriers limit access to such services. We conducted a scoping review to summarize evidence on the barriers and facilitators of CVD prevention services among women with prior GDM or HDP. Methods and results A comprehensive search strategy was used to search articles published in three databases (Ovid Medline, CINAHL, Embase). Studies published in English or French that investigated and reported barriers or facilitators to postpartum CVD screening and preventive care among women with previous GDM and HDP were included. Out of 18 565 studies we screened, 29 studies (12 qualitative, 17 quantitative) were included. Main individual level barriers including lack of knowledge, health, and emotional factors were identified. Competing priorities, lack of family/friend support, and mistrust of healthcare providers were the most reported interpersonal level barriers, while gaps in communication were the most significant organizational barrier, and gaps in insurance coverage was the most reported system barrier. Individual level facilitators included a personal desire for better health and availability of postpartum programmes, and the most reported interpersonal facilitator was women's commitment to modelling a healthy lifestyle for their children. Organizational level facilitators were access to primary care providers and follow-up visit reminders, and programme availability in native languages. Conclusion Women with prior GDM or HDP face significant barriers to accessing postpartum CVD prevention services. These barriers ranged from individual-level knowledge gaps to system-level healthcare disparities.