Citations

Abstract Pathogenic protein-truncating variants of RAD51C, which plays an integral role in promoting DNA damage repair, increase the risk of breast and ovarian cancer. A large number of RAD51C missense variants of uncertain significance (VUS) have been identified, but the effects of the majority of these variants on RAD51C function and cancer predisposition have not been established. Here, analysis of 173 missense variants by a homology-directed repair (HDR) assay in reconstituted RAD51C−/− cells identified 30 nonfunctional (deleterious) variants, including 18 in a hotspot within the ATP-binding region. The deleterious variants conferred sensitivity to cisplatin and olaparib and disrupted formation of RAD51C/XRCC3 and RAD51B/RAD51C/RAD51D/XRCC2 complexes. Computational analysis indicated the deleterious variant effects were consistent with structural effects on ATP-binding to RAD51C. A subset of the variants displayed similar effects on RAD51C activity in reconstituted human RAD51C-depleted cancer cells. Case–control association studies of deleterious variants in women with breast and ovarian cancer and noncancer controls showed associations with moderate breast cancer risk [OR, 3.92; 95% confidence interval (95% CI), 2.18–7.59] and high ovarian cancer risk (OR, 14.8; 95% CI, 7.71–30.36), similar to protein-truncating variants. This functional data supports the clinical classification of inactivating RAD51C missense variants as pathogenic or likely pathogenic, which may improve the clinical management of variant carriers. Significance: Functional analysis of the impact of a large number of missense variants on RAD51C function provides insight into RAD51C activity and information for classification of the cancer relevance of RAD51C variants.

Abstract Background: The ATEMPT trial primary analysis found that one year of adjuvant trastuzumab emtansine (T-DM1) achieved a 3-year iDFS of 97.8% for patients with stage I HER2+ breast cancer, but was not associated with fewer clinically relevant toxicities (CRTs) compared with paclitaxel and trastuzumab (TH). In this end-of-study analysis, we report 5-year survival outcomes and correlative analyses from the trial. Methods: Patients with stage I centrally confirmed HER2+ breast cancer were randomly assigned 3:1 to adjuvant T-DM1 for one year or TH and received T-DM1 3.6 mg/kg IV every 3 weeks for 17 cycles or paclitaxel 80 mg/m2 IV with weekly trastuzumab IV followed by trastuzumab for 9 months. The co-primary objectives were to compare the incidence of CRTs between the 2 arms and to evaluate iDFS in patients receiving T-DM1. To investigate proteomic correlates of recurrence, spatial proteomic analyses were performed on samples from 13 patients experiencing iDFS events (cases) and 24 matched controls using the NanoString GeoMx Digital Spatial Profiler. The impact of HER2 heterogeneity on outcomes was investigated among 17 cases and 51 matched controls by fluorescence in-situ hybridization (FISH). HER2 genetic heterogeneity was assessed by scrutinizing the whole tumor area and defined as the occurrence of HER2 gene amplification in >5% but < 50% invasive tumor cells. The risk of recurrence was evaluated centrally with the HER2DX genomic assay from 225 primary tumor samples. Germline whole genome sequencing (WGS) was conducted among 55 patients experiencing T-DM1-induced thrombocytopenia and/or bleeding and 55 matched controls to identify genomic correlates for this side effect. Results: A total of 497 patients who initiated protocol therapy were included in this analysis (383 T-DM1 and 114 TH). After a median follow up 5.8 years, among patients receiving T-DM1 there were a total of 11 iDFS events, with 3 distant recurrences. The 5-year iDFS for T-DM1 was 97.0% (95% CI, 95.3-98.8%), the 5-year recurrence-free interval (RFI) was 98.6% (95% CI: 97.4-99.8%) and the 5-year overall survival (OS) for T-DM1 was 97.8 % (95% CI, 96.3-99.3%). Although the study was not powered to evaluate the efficacy of TH, among the 114 patients receiving TH, a total of 9 iDFS events were observed, including 2 distant events; the 5-year iDFS with TH was 91.3% (95% CI: 86.0-96.9%), 5-year RFI was 93.3% (95% CI: 88.6-98.2%) and 5-year OS was 97.9% (95% CI: 95.2-100%). A total of 56 samples were evaluable for heterogeneity analyses, among which 14% (n=8) harbored HER2 genetic heterogeneity. Spatial proteomic analyses found that NF1 (adjusted p=0.72 × 10-6) and CTLA-4 (adjusted p=0.15 × 10-3) were significantly upregulated in primary samples from cases, while cleaved caspase 9, CD25, GITR, ICOS, p53 and PD-L2 were significantly upregulated in controls (all with adjusted p< 0.05). Germline WGS found that the top gene associations with thrombocytopenia and thrombocytopenia or bleeding were ALMS1 (p=0,19 × 10-3) and APBA3 (p=0,23 × 10-3), respectively, although none reaching the threshold for genome wide significance. rs62143195 and rs114169776 were the top single nucleotide polymorphisms associated with thrombocytopenia and thrombocytopenia or bleeding, respectively. Data on the impact of HER2 heterogeneity and of HER2DX score on survival outcomes will be presented. Conclusion: With longer follow-up, adjuvant T-DM1 confirmed outstanding long-term outcomes among patients with stage I HER2+ breast cancer, demonstrating a 5-year RFI of 98.6%. Spatial proteomic analyses identified a potential association between NF1 and CTLA-4 expression with recurrence. Details on the impact of HER2 heterogeneity and HER2DX assay on prognosis will be presented. Citation Format: Paolo Tarantino, Nabihah Tayob, Chau T Dang, Denise Yardley, Steven J. Isakoff, Vicente Valero, Meredith Faggen, Therese Mulvey, Ron Bose, Douglas Weckstein, Antonio C. Wolff, Katherine Reeder-Hayes, Hope Rugo, Bhuvaneswari Ramaswamy, Dan Zuckerman, Lowell Hart, Vijayakrishna K. Gadi, Michael Constantine, Kit Cheng, Audrey Merrill Garrett, Paul K. Marcom, Kathy S. Albain, Patricia DeFusco, Nadine Tung, Blair Ardman, Rita Nanda, Rachel C. Jankowitz, Mothaffar Rimawi, Vandana Abramson, Paula R. Pohlmann, Catherine Van Poznak, Andres Forero-Torres, Minetta C. Liu, Kathryn Ruddy, Yue Zheng, Romualdo Barroso-Sousa, Adrienne Waks, Michelle K. DeMeo, Molly K. DiLullo, Giuseppe Curigliano, Harold Burstein, Ann Partridge, Eric Winer, Giuseppe Viale, Winnie Hui, Elizabeth A. Mittendorf, Bryan P. Schneider, Aleix Prat, Ian Krop, Sara Tolaney. Adjuvant Trastuzumab Emtansine Versus Paclitaxel plus Trastuzumab for Stage I HER2+ Breast Cancer: 5-year results and correlative analyses from ATEMPT (TBCRC033) [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr PD18-01.

Abstract Purpose To estimate the risk of contralateral breast cancer (CBC) among women in the general population with germline pathogenic variants (PVs) in ATM, BRCA1, BRCA2, CHEK2, and PALB2. Methods Among 15,104 prospectively followed women within the CARRIERS study treated with ipsilateral surgery for invasive breast cancer, a subset of 14,237 women were identified from population-based studies. The risk of CBC was estimated for PV carriers in each gene compared to women without PVs in a multivariate proportional hazard regression analysis accounting for the competing risk of death and adjusting for patient and tumor characteristics. The primary analyses focused on the overall cohort and on women from the general population. Secondary analyses examined associations by race/ethnicity, age at primary breast cancer diagnosis, menopausal status, and tumor estrogen receptor status. Results Germline BRCA1, BRCA2, and CHEK2 PV carriers with breast cancer were at significantly elevated risk (Hazard ratio ≥ 1.9, p< 0.05) of CBC, whereas only the PALB2 PV carriers with ER-negative breast cancer had elevated risks. In contrast, ATM PV carriers did not have significantly increased CBC risks. African American PV carriers had similarly elevated risks of CBC as non-Hispanic White PV carriers. Among premenopausal women, the 15-year cumulative incidence of CBC was >20% for BRCA1, BRCA2 and CHEK2 PV carriers with breast cancer, and for PALB2 PV carriers with ER-negative breast cancer. The 15-year cumulative incidence of CBC among postmenopausal PV carriers was < 20% for PV carriers in any of the 5 genes. Conclusions Women diagnosed with breast cancer and known to carry germline PVs in BRCA1, BRCA2, CHEK2, or PALB2 are at substantially increased risk of CBC and may benefit from enhanced surveillance and risk-reduction strategies. Citation Format: Siddhartha Yadav, Nicholas J. Boddicker, Jie Na, Eric C. Polley, Chunling Hu, Steven N. Hart, Rohan D. Gnanaolivu, Nicole Larson, Carolyn Dunn, Susan Holtegaard, Huaizhi Huang, Lauren R. Teras, Alpa V. Patel, James V. Lacey Jr., Susan Neuhausen, Leslie Bernstein, Elena Martinez, Christopher Haiman, Fei Chen, Kathryn Ruddy, Janet Olson, Esther John, Allison W. Kurian, Dale P. Sandler, Katie M. O’Brien, Jack A. Taylor, Clarice R. Weinberg, Hoda Anton-Culver, Argyrios Ziogas, Gary R. Zirpoli, David E. Goldgar, Katherine L. Nathanson, Susan Domchek, Julie R. Palmer, Jeffrey Weitzel, Peter Kraft, Fergus J. Couch. Population-based Estimates of contralateral Breast Cancer Risk among Carriers of Germline Pathogenic Variants in ATM, BRCA1, BRCA2, CHEK2, and PALB2 [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr GS4-04.

Mutations that predispose to familial pheochromocytoma and paraganglioma include inherited variants in the four genes ( SDHA , SDHB , SDHC and SDHD ) encoding subunits of succinate dehydrogenase (SDH), an enzyme of the mitochondrial tricarboxylic acid cycle and complex II of the electron transport chain. In heterozygous variant carriers, somatic loss of heterozygosity is thought to result in tumorigenic accumulation of succinate and reactive oxygen species. Inexplicably, variants affecting the SDHB subunit predict worse clinical outcomes. Why? Here we consider two hypotheses. First, relative to SDH A, C and D subunits, the small SDHB subunit might be more intrinsically ‘fragile’ to missense mutations because of its relatively large fraction of amino acids contacting prosthetic groups and other SDH subunits. We show evidence that supports this hypothesis. Second, the natural pool of human SDHB variants might, by chance, be biased toward severe truncating variants and missense variants causing more disruptive amino acid substitutions. We tested this hypothesis by creating a database of known SDH variants and predicting their biochemical severities. Our data suggest that natural SDHB variants are more pathogenic. It is unclear if this bias is sufficient to explain clinical data. Other explanations include the possibility that SDH subcomplexes remaining after SDHB loss have unique tumorigenic gain-of-function characteristics, and/or that SDHB may have additional unknown tumor-suppressor functions.

Background: Rare genetic variants are emerging as important contributors to the heritability of multiple sclerosis (MS). Whether rare variants also contribute to pediatric-onset multiple sclerosis (POMS) is unknown. Objective: To test whether genes harboring rare variants associated with adult-onset MS risk ( PRF1, PRKRA, NLRP8 , and HDAC7 ) and 52 major histocompatibility complex (MHC) genes are associated with POMS. Methods: We analyzed DNA samples from 330 POMS cases and 306 controls from the US Network of Pediatric MS Centers and Kaiser Permanente Northern California for which Illumina ExomeChip genotypes were available. Using the gene-based method “SKAT-O,” we tested the association between candidate genes and POMS risk. Results: After correction for multiple comparisons, one adult-onset MS gene ( PRF1, p = 2.70 × 10 −3 ) and two MHC genes ( BRD2, p = 5.89 × 10 −5 and AGER, p = 7.96 × 10 −5 ) were significantly associated with POMS. Results suggest these are independent of HLA-DRB1*1501. Conclusion: Findings support a role for rare coding variants in POMS susceptibility. In particular, rare minor alleles within PRF1 were more common among individuals with POMS compared to controls while the opposite was true for rare variants within significant MHC genes, BRD2 and AGER . These genes would not have been identified by common variant studies, emphasizing the merits of investigating rare genetic variation in complex diseases.

Abstract Background Current guidelines recommend endoscopic resection of visible and endoscopically resectable colorectal colitis-associated neoplasia (CAN) in patients with inflammatory bowel disease (IBD). However, patients with high risk CAN are often not amenable to conventional resections techniques and a consensus approach for the endoscopic management of these lesions is presently lacking. This Delphi study aims to reach consensus amongst experts on the endoscopic management of these lesions. Methods A three-round modified Delphi process was conducted to reach consensus amongst worldwide IBD and/or endoscopy experts (n=18) from three continents. Experts were chosen based on the extensive clinical experience with IBD and/or EMR/ESD in patients with IBD, and the authorship on multiple peer-reviewed publications on CAN, the endoscopic resection of CAN and/or EMR/ESD. Consensus was considered if ≥ 75% agreed or disagreed. Quality of evidence was assessed by the criteria of the Cochrane Collaboration group. Results Consensus was reached on all statements (n=14). Experts agreed on a definition for CAN and high-risk CAN (HR-CAN). Consensus was reached on the examination of the colon with enhanced endoscopic imaging prior to resection, the endoscopic resectability of a HR-CAN lesion and endoscopic assessment and standard report of CAN lesions. In addition, experts agreed on type of resections of HR-CAN (< 20mm, >20 mm, with or without good lifting), endoscopic success (technical success and outcomes), histologic assessment and follow-up in HR-CAN. Conclusion This is the first step in developing international consensus-based recommendations for endoscopic management of (HR-)CAN. Although the quality of available evidence was considered low, consensus was reached on several aspects of the management of (HR-)CAN. The present work and proposed standardization might benefit future studies.

Abstract Background Crohn’s disease (CD) and ulcerative colitis (UC), together known as inflammatory bowel diseases (IBD), affect approximately seven million people globally. The continuous rise in IBD prevalence and the aging of populations will inevitably lead to an increasing use of health care resources. In parallel with these trends, continuing innovations in IBD therapeutics, diagnostics, and preventatives are creating more options for IBD patients seeking to reduce their disease burden. These trends pose an imminent burden on health care systems and require that we identify modifiable cost drivers in IBD care and develop strategies for delivering equitable and affordable care for all patients. Methods This Lancet Gastroenterology & Hepatology Commission, consisting of a diverse faculty of health care professionals with expertise in the field of IBD and health economists, was formed to deliver an extensive summary of the literature and discuss key topics on the costs and cost-effectiveness of treating IBD in the present, and how this is likely to look in the future. Furthermore, it offers suggestions for how to deliver affordable IBD care in the coming years. The report’s focus was on high-income countries in Europe, North America, Australia and New Zealand, and Asia. Results The Commission drew together a wide range of expertise to discuss the current costs of IBD care, the drivers of increasing costs, as well as how to deliver affordable care for IBD in the future. The key conclusions are that (i) increases in health care costs must be evaluated against improved disease control and reductions in indirect costs, and (ii) that overarching systems for data interoperability, registries, and big data approaches must be established for continuous assessment of effectiveness, costs, and cost-effectiveness of care. International collaborations should be sought in order to evaluate novel models of care (such as value-based health care, including integrated health care and participatory health care models), as well as to improve the education and training of clinicians, patients, and policymakers. Measures to reduce the costs of IBD care are summarised in Table 1. Conclusion Increases in health care costs must be evaluated against improved disease control and reductions in indirect costs. Evaluations should be systematically aligned between countries and regions. Detailed analysis of the current epidemiology and the likely effects of changing IBD management on disease course and socioeconomic outcomes is essential; and will become even more imperative in the era of precision medicine, where complex biotechnologies will require expensive analyses, highly skilled personnel, and drug development for what may sometimes be relatively small patient groups.

PURPOSE To estimate the risk of contralateral breast cancer (CBC) among women with germline pathogenic variants (PVs) in ATM, BRCA1, BRCA2, CHEK2, and PALB2. METHODS The study population included 15,104 prospectively followed women within the CARRIERS study treated with ipsilateral surgery for invasive breast cancer. The risk of CBC was estimated for PV carriers in each gene compared with women without PVs in a multivariate proportional hazard regression analysis accounting for the competing risk of death and adjusting for patient and tumor characteristics. The primary analyses focused on the overall cohort and on women from the general population. Secondary analyses examined associations by race/ethnicity, age at primary breast cancer diagnosis, menopausal status, and tumor estrogen receptor (ER) status. RESULTS Germline BRCA1, BRCA2, and CHEK2 PV carriers with breast cancer were at significantly elevated risk (hazard ratio > 1.9) of CBC, whereas only the PALB2 PV carriers with ER-negative breast cancer had elevated risks (hazard ratio, 2.9). By contrast, ATM PV carriers did not have significantly increased CBC risks. African American PV carriers had similarly elevated risks of CBC as non-Hispanic White PV carriers. Among premenopausal women, the 10-year cumulative incidence of CBC was estimated to be 33% for BRCA1, 27% for BRCA2, and 13% for CHEK2 PV carriers with breast cancer and 35% for PALB2 PV carriers with ER-negative breast cancer. The 10-year cumulative incidence of CBC among postmenopausal PV carriers was 12% for BRCA1, 9% for BRCA2, and 4% for CHEK2. CONCLUSION Women diagnosed with breast cancer and known to carry germline PVs in BRCA1, BRCA2, CHEK2, or PALB2 are at substantially increased risk of CBC and may benefit from enhanced surveillance and risk reduction strategies.

Abstract Background Network-connected medical devices have rapidly proliferated in the wake of recent global catalysts, leaving clinical laboratories and healthcare organizations vulnerable to malicious actors seeking to ransom sensitive healthcare information. As organizations become increasingly dependent on integrated systems and data-driven patient care operations, a sudden cyberattack and the associated downtime can have a devastating impact on patient care and the institution as a whole. Cybersecurity, information security, and information assurance principles are, therefore, vital for clinical laboratories to fully prepare for what has now become inevitable, future cyberattacks. Content This review aims to provide a basic understanding of cybersecurity, information security, and information assurance principles as they relate to healthcare and the clinical laboratories. Common cybersecurity risks and threats are defined in addition to current proactive and reactive cybersecurity controls. Information assurance strategies are reviewed, including traditional castle-and-moat and zero-trust security models. Finally, ways in which clinical laboratories can prepare for an eventual cyberattack with extended downtime are discussed. Summary The future of healthcare is intimately tied to technology, interoperability, and data to deliver the highest quality of patient care. Understanding cybersecurity and information assurance is just the first preparative step for clinical laboratories as they ensure the protection of patient data and the continuity of their operations.

Abstract Obesity is associated with several skeletal muscle impairments which can be improved through an aerobic exercise prescription. The possibility that exercise responsiveness is diminished in people with obesity has been suggested but not well‐studied. The purpose of this study was to investigate how obesity influences acute exercise responsiveness in skeletal muscle and circulating amino metabolites. Non‐obese (NO; n = 19; 10F/9M; BMI = 25.1 ± 2.8 kg/m 2 ) and Obese (O; n = 21; 14F/7M; BMI = 37.3 ± 4.6 kg/m 2 ) adults performed 30 min of single‐leg cycling at 70% of VO 2 peak. 13 C 6 ‐Phenylalanine was administered intravenously for muscle protein synthesis measurements. Serial muscle biopsies (vastus lateralis) were collected before exercise and 3.5‐ and 6.5‐h post‐exercise to measure protein synthesis and gene expression. Targeted plasma metabolomics was used to quantitate amino metabolites before and 30 and 90 min after exercise. The exercise‐induced fold change in mixed muscle protein synthesis trended ( p = 0.058) higher in NO (1.28 ± 0.54‐fold) compared to O (0.95 ± 0.42‐fold) and was inversely related to BMI (R 2 = 0.140, p = 0.027). RNA sequencing revealed 331 and 280 genes that were differentially expressed after exercise in NO and O, respectively. Gene set enrichment analysis showed O had six blunted pathways related to metabolism, cell to cell communication, and protein turnover after exercise. The circulating amine response further highlighted dysregulations related to protein synthesis and metabolism in adults with obesity at the basal state and in response to the exercise bout. Collectively, these data highlight several unique pathways in individuals with obesity that resulted in a modestly blunted exercise response.