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Clonal acquisition of multiple chromosomal abnormalities in hematopoietic stem and progenitor cells (HSPCs) is a hallmark of high-risk acute myeloid leukemias with complex karyotype (AML-CK). AML-CK is associated with TP53 mutations and chromosome 5q deletions (del5q); however, the drivers and clonal trajectories of aneuploid evolution in HSPCs remain unknown. We have developed a patient-derived induced pluripotent stem cell (iPSC) model in which preleukemic HSPCs clonally evolve to distinct, highly aneuploid states following transient mitotic inhibition. By tracking chromosome evolution at single cell resolution, we show that TP53-mutant HSPCs with del5q, but not TP53­ mutation alone, evolved complex chromosomal changes. Clonal evolution was marked by stepwise acquisition of numerical and structural chromosome changes seen in AML-CK patients, with individual abnormalities conferring fitness advantage. iPSC-derived aneuploid HSPCs and primary AML-CK patient samples exhibited a conserved gene expression signature marked by upregulation of PTEN, cohesins, and anti-apoptotic factor BCL2, indicative of a shared aneuploid cell state in HSPCs. Clinical BCL2 inhibitor venetoclax eradicated BCL2-dependent aneuploid clones, with resistant clones undergoing a lineage switch to upregulate alternative BCL2 factors. In summary, we demonstrate that mutant TP53 and del5q drive chromosome evolution marked by stepwise acquisition of individual abnormalities. Moreover, aneuploid HSPCs exhibit a shared gene expression state which confers unique targetable therapeutic vulnerabilities in AML-CK.

Background: Hypoplastic left heart syndrome (HLHS) is defined as “a spectrum of congenital cardiovascular malformations with normally aligned great arteries without a common atrioventricular junction, characterized by underdevelopment of the left heart with significant hypoplasia of the left ventricle including atresia, stenosis, or hypoplasia of the aortic or mitral valve, or both valves, and hypoplasia of the ascending aorta and aortic arch”. Without treatment, HLHS is usually lethal in the neonate. Many hypotheses have been advanced to explain the etiology of HLHS; however, no single theory appears to fully explain the phenotypic variability seen in HLHS. Furthermore, many of these theories offer no explanations regarding the precipitating events which lead to the development of HLHS. Objective: This review considers and critically evaluates the strengths and weaknesses of the leading theories proposed to explain the pathogenesis of HLHS—including hemodynamic disturbances, primary myocardial structural defects, valvar malformations, and genetic or epigenetic alterations that may provoke developmental and anatomic abnormalities. After presenting each model, we propose a novel, comprehensive, and data-driven framework which may assist researchers in developing models for the pathogenesis of the various subtypes of HLHS. Methods: Key findings from human fetal imaging, histopathology, genetic studies, and animal models were considered, as well as the hypothetical contribution of each in observed HLHS phenotypes. The rationales for these findings as causal factors initiating individual HLHS patterns, as well as how they might contribute to HLHS in general, were critically analyzed. Results: The flow theory is strongly supported by animal models and in utero interventions that demonstrate the impact of altered hemodynamics on cardiac morphogenesis. However, the flow theory fails to identify initial causes of disturbed flow or related histological features of HLHS like endocardial fibroelastosis. The myocardial and valve-first models suggest an important role in developmental defects, but do not necessarily have a strong experimental basis that provides explanations for how they mediate HLHS. Genetic studies in patients with HLHS have identified several candidate causal mutations. However, such genetic causes of HLHS exhibit incomplete phenotypic penetrance and clinical impact. A multifactorial framework attempts to integrate these diverse mechanisms and may provide the most coherent explanation that can accommodate the heterogeneity and variable presentation of HLHS. Such a framework may identify multiple forces that drive disease but does not provide useful pathways for future research about HLHS. Conclusions: No single hypothesis has fully explained how HLHS is initiated, progresses, and presents with the clinical conditions that are encountered by cardiac surgeons and cardiologists. The most current models suggest that the spectrum of HLHS reflects acomplex interaction between genetic susceptibility, flow-dependent cardiac remodeling, and environmental factors in utero. A multifactorial model integrates these diverse mechanisms and may provide the most coherent explanation for the various phenotypic variations in HLHS. Based on our analysis of the most current data and the strengths and weaknesses of the current theoretical frameworks, we propose a novel research strategy aimed at identifying specific cardiac progenitor cell populations whose dysregulation may represent a unifying explanation for the etiology of the various phenotypes of HLHS. Based on the arguments made throughout this manuscript that evaluate the various genetic, structural, and hemodynamic models of initiation of disease, we believe that the significant phenotypic variability across the spectrum of HLHS (i.e., the different anatomic subtypes for “classic” HLHS) most likely reflects different underlying etiologies and mechanisms. At the very least, it is very likely that the timing of the insult is critical in determining anatomic subtype. Based on the published data and the arguments within this manuscript, it seems naive to think that there is a single unifying mechanism explain all forms of HLHLS.

Abstract Background Vorasidenib is Food and Drug Administration‐approved for treatment of grade 2 isocitrate dehydrogenase (IDH)–mutant gliomas and has demonstrated a benefit in progression‐free survival compared to a placebo. This study assessed the cost‐effectiveness of this treatment strategy compared to standard treatment: observation or chemoradiation (CRT). Methods The authors used an integrated Markov model to compare quality‐adjusted life‐years (QALY) gained and cost‐effectiveness of patients with IDH‐mutated low‐grade glioma (LGG) treated with vorasidenib, observation, or CRT. Outcomes were expressed as incremental cost‐effectiveness ratios (ICERs) per QALY gained. Treatment is considered cost‐effective if it meets the commonly accepted willingness‐to‐pay threshold of $100,000 per QALY gained. Results Based on model parameters, vorasidenib demonstrated an ICER of $356,756 per QALY when compared to CRT. When compared to observation, vorasidenib demonstrated an improved ICER of $215,191 per QALY. On one‐way sensitivity analysis compared to observation, median cost of vorasidenib and median overall survival were most likely to affect ICER with only marginal changes on analysis of other model factors. For ICER to become ≤$100,000 compared to observation, the cost of vorasidenib would need to drop to below $14,072 monthly or have a median survival gain of at least 11.9 years. The probabilistic sensitivity analysis demonstrated that vorasidenib was favored in none of 5000 Monte Carlo iterations. Conclusion Using the best available data, the current price of vorasidenib does not meet commonly accepted cost‐effectiveness thresholds in treatment of IDH‐mutated LGGs.

Introduction Lynch syndrome (LS) is a hereditary cancer syndrome that increases risk for colorectal and other cancers. We hypothesize that vaccines against tumor-associated antigens CEA, MUC1, and brachyury, simultaneously delivered in an adenovirus serotype-5 vector (Tri-Ad5) combined with the immune-enhancing IL-15 receptor superagonist nogapendekin-alfa-inbakicept (NAI) will reduce the incidence of colorectal neoplasms in LS carriers. Methods In this ongoing phase IIB double-blind placebo-controlled trial, two open-label safety phases (SPs) assessed safety of Tri-Ad5 alone (SP1, n=10) and with added NAI (SP2, n=10). A randomized controlled trial (RCT) follows the SPs. After baseline colonoscopy, vaccine dosing occurs at weeks 0, 4 and 8; Tri-Ad5 alone in SP1 and Tri-Ad5 plus NAI in SP2, with identical boosters at Week 52. The RCT phase participants (n=138) were randomized to receive Tri-Ad5 plus NAI or placebo. All participants complete colonoscopy at Weeks 52 and 104 for assessment of the primary endpoint: cumulative colorectal neoplasm incidence. Secondary endpoints include safety, tolerability, and immunogenicity. Results All 20 SP participants (median age 57.5 (range 42–75), 70% female, 15% minority) received all prime and booster series. SP1 participants reported 139 adverse events (AEs) and SP2 participants reported 178. AEs were predominantly grade 1; no treatment-related serious adverse events (SAEs) occurred. The most common treatment-related AEs were reactogenic events including grade 3 rash (without skin necrosis or breakdown) at NAI injection site (100% of SP2 participants). The RCT phase (n=138) recently completed accrual. Discussion In LS carriers without active cancer, the combination of Tri-Ad5 + NAI was well-tolerated; the RCT phase is ongoing. Clinical Trial Registration https://clinicaltrials.gov/study/ , identifier NCT05419011.

Abstract Inflammatory bowel diseases (IBD), principally Crohn’s disease (CD) and ulcerative colitis (UC), are common chronic disorders involving inflammation and often progressive tissue damage. Genome-wide association studies have mapped many risk signals, but the causal variants, effector genes and relevant cellular contexts remain difficult to resolve, limiting mechanistic interpretation and therapeutic translation. Here we performed a multi-ancestry GWAS meta-analysis of 125,992 individuals with IBD and more than 1.2 million controls, identifying 619 independent association signals (374 novel) at 420 IBD regions that account for 77–80% of SNP-based heritability. Fine-mapping resolved 81 high-confidence variants, 41 not previously reported. Although most signals were shared between CD and UC, 39% showed IBD subtype specificity, with UC signals showing stronger enrichment in functional annotations from intestinal epithelial, secretory and enteroendocrine cells, and CD showing stronger genetic correlations with circulating inflammatory biomarkers, including C-reactive protein and glycoprotein acetylation. Latent causal modelling supported a causal effect of decreased high-density lipoprotein on CD risk. By integrating bulk and single-cell eQTL and pQTL resources using colocalisation and Mendelian randomisation, together with coding-variant evidence from exome sequencing, we prioritised 664 candidate effector genes across 341 signals, including 390 newly implicated IBD genes, revealing new biological mechanisms and candidate therapeutic targets supported by human genetics.

PURPOSE We sought to characterize outcome associations of poly ADP-ribose polymerase inhibitors (PARPi) in patients with ovarian cancer (OVCA) whose cancers contain homozygous loss (deletions) of homologous recombination repair (HRR) pathway genes, an alteration class not uniformly reported on clinical testing and not susceptible to acquired resistance via secondary reversion mutations. METHODS This study used US-based deidentified Flatiron Health-Foundation Medicine OVCA Clinico-Genomic Database. Patients with advanced OVCA and genomic profiling by Foundation Medicine were assembled into cohorts evaluating PARPi monotherapy use, and separately, PARPi maintenance therapy use, with outcomes associated with HRR gene alterations: BRCA1 / 2 , PALB2 , RAD51B/C/D , BARD1 , and BRIP1 . RESULTS 1.5% (82/5,404) had HRR gene homozygous loss, with BRCA1 and BRCA2 loss being most common. Among all OVCAs with BRCA1/2 alterations, 7.5% (63/836) were homozygous losses. Most BRCA1 (34/38, 89%) and BRCA2 (18/25, 72%) homozygous losses were intragenic, with breakpoints not spanning entire gene. Maintenance cohort: 22 patients had HRR gene homozygous loss, with strongly improved progression-free survival (PFS) for PARPi versus no PARPi use (HR, 0.06, 95% CI, 0.01 to 0.37). Monotherapy cohort: patients without HRR alterations (n = 198), HRR mutations or rearrangements (n = 93), and HRR homozygous loss (n = 8) had median PFS of 4.9, 10.6, and 25.4 months, and median overall survival of 18.5, 22.5, and 51.8 months, respectively. CONCLUSION We observe durable PARPi effectiveness for patients with OVCA and HRR gene homozygous loss in routine practice. We demonstrate the importance of detecting and reporting homozygous loss in HRR genes, an aspect not standard to all sequencing assays.

PURPOSE The Lynch syndrome (LS) genes, MLH1 , MSH2 , MSH6 , and PMS2 , are considered to be some of the highest-priority genes to be tested for population genomic screening, with the aim to prevent and detect cancers early in those with a higher risk for such diagnoses. The objective of this study was to determine the risk of cancer associated with pathogenic variants in MLH1 , MSH2 , MSH6 , or PMS2 in the general population to build evidence-based guidelines for population genomic screening METHODS This retrospective case-control study uses Helix Research Network data from 230,159 participants across nine US health systems. Variant interpretation was performed following the American College of Medical Genetics and Association for Molecular Pathology guidelines. Clinical diagnoses were identified from electronic health records and claims data for 11 cancer types associated with LS, including colorectal and endometrial cancers. RESULTS Individuals with pathogenic variants in MLH1 , MSH2 , and MSH6 showed substantial risk for LS-related cancers compared with those without pathogenic variants. Conversely, individuals with pathogenic variants in PMS2 had no increase in risk for all 11 LS-associated cancers with hazard ratio (HR) of 1.0 (95% CI, 0.6 to 1.8) compared with those without a pathogenic variant. There was a small increase in risk when restricting the analysis to colorectal cancer with an HR of 3.5 (1.7-7.4). This increase in colorectal cancer risk was predominantly observed after age 60 years, 10 years after US Preventive Services Task Force guidelines recommend starting colonoscopies for the average population. Up to age 60 years, 2.6% of individuals with PMS2 pathogenic variants were diagnosed with colorectal cancer, closer to the general population (0.7%) than those with MLH1 (37.3%), MSH2 (28.9%), or MSH6 (6.7%) pathogenic variants. For 100,000 individuals screened for PMS2 , 854 additional colonoscopies would be performed, which would prevent or detect early 3.2 colorectal cancers. CONCLUSION This analysis across nine health systems highlights the clinical phenotypes of PMS2 pathogenic germline variants in the entire population.

Obesity is a complex metabolic disease that is the leading risk factor for cardiovascular disease. In obesity, adipose arteries exhibit robust endothelial dysfunction (ED). A major hallmark of ED is loss in flow induced vasodilation (FIV). Kir2.1 is an inwardly rectifying K+ channel that contributes to FIV through the downstream production of nitric oxide, a potent vasodilator. Work from our group demonstrated that in addition to loss in FIV, endothelial cells (ECs) isolated from obese mice exhibited blunted Kir2.1 currents. Plasma long chain fatty acids (LCFAs) are well established to be elevated in obesity and have been separately shown to inhibit Kir2.1 channels. CD36 is the major fatty acid translocase responsible for the uptake of LCFAs and we therefore aimed to determine if CD36 was contributing to this loss in Kir2.1 function. We previously showed that global CD36 ablation restores endothelium-dependent dilations to flow. These findings prompted us to explore the role of EC CD36 in negatively regulating Kir2.1 function. We performed patch clamp electrophysiology experiments on freshly isolated ECs from the Tie2eCreCD36fl/fl model and determined that EC CD36 ablation restores Kir2.1 currents in obesity. To further explore the established relationship between Kir2.1 and FIV, we performed ex vivo pressure myography experiments to evaluate endothelial dependent dilations to flow. EC CD36 ablation restored responses to flow in arteries from obese mice, an effect that could be blunted by inhibiting Kir2.1 suggesting that CD36 ablation in endothelium rescues the Kir2.1 contribution to FIV. To determine if obesity alters the expression of endothelial CD36, arteries from mice and humans undergoing bariatric surgery were isolated and en face preparations were stained to locate the EC layer and assess CD36 expression. Confocal imaging of en face arteries coupled with flow cytometry on isolated endothelial cells revealed that obesity did not alter the expression of CD36 in endothelium of mesenteric arteries relative to controls in WT mice or humans. As expression did not change, we next probed functionality of CD36 in obese vs. control in mice and humans. Arteries were exposed to a fluorescent fatty acid, BODIPY C-16, at various time points followed by en face preparations and confocal microscopy. As expected, obese vessels exhibited elevated amounts of fatty acid uptake (FAU) at all time points relative to control in mice and humans, suggesting an increase in CD36. To further confirm this change in function, we repeated FAU experiments in the Tie2eCreCD36fl/fl model and found that EC CD36 ablation attenuated FAU in obese vessels compared to both their lean and genotype controls. Taken together, this work suggests that an increase in CD36 function drives impairment of Kir2.1. This work establishes a CD36/Kir2.1 axis worthy of further exploration including understanding how CD36 and LCFAs are impairing Kir2.1 upstream. This abstract was presented at the American Physiology Summit 2026 and is only available in HTML format. There is no downloadable file or PDF version. The Physiology editorial board was not involved in the peer review process.

Background: Cardiovascular-Kidney-Metabolic (CKM) syndrome entails pathophysiological interactions leading to multiorgan dysfunction and a high rate of cardiovascular morbidity and mortality, largely driven by the development of heart failure (HF). Mechanisms leading to HF in CKM syndrome are unknown. We created a model of CKM syndrome in swine and showed that cardiac abnormalities associate with cardiac microvascular (MV) rarefaction and decreased expression and availability of VEGF. Emerging research focuses on micro-RNAs (miRNAs) and their role in the pathophysiology of HF, but whether they play a role in the development of cardiac injury in CKM syndrome via VEGF modulation has not been investigated. We aimed to identify specific miRNAs that can target VEGF to test the hypothesis that their direct cardiac inhibition will rescue cardiac VEGF, improve angiogenic signaling, and cardiac hemodynamics in CKM syndrome. Methods: CKM (bilateral renal artery stenosis+high-cholesterol/high-carbohydrate feeding) and normal pigs (n=4 each, 2 males/2 females) were studied for 14 weeks. Unbiased micro-RNA sequencing identified 26 miRNAs differentially expressed in CKM pig hearts, of which only miR-452-5p can target VEGFA, which was confirmed by pulldown analysis and qPCR. In addition, CKM (n=4, 2 males/2 females) were treated after 6 weeks with a single intracoronary (IC) administration of a miR-452-5p inhibitor (antagomiR). Cardiac hemodynamics (echocardiography), MV architecture (3D micro-CT) and cardiac expression of VEGF and miR-452-5p (RT-qPCR) were quantified before IC miR-452-5p inhibition, and again at the end of the study (14 weeks). Results: Pigs with CKM syndrome showed blunted diastolic relaxation, increased cardiac remodeling, and reduced subendocardial MV density and cardiac VEGF expression, accompanied by higher cardiac expression of miR-452-5p compared to normal pigs. Notably, most of these parameters were improved after in vivo IC miR-452-5p inhibition (single dose). Blood pressure was unchanged ( Table 1 ). Conclusions: Our study supports a role for VEGF in preserving cardiac MV integrity in CKM syndrome. Also, it identifies a targeted post-transcriptional regulation of VEGF via miR-452-5p and supports the feasibility and efficacy of its mechanistic modulation in vivo. The predictive power of our model conceptually supports the potential of a novel targeted intervention to protect the heart in CKM syndrome. [Table: see text] Support: NIH AG084154 (ARC), and DK129240 (AE) This abstract was presented at the American Physiology Summit 2026 and is only available in HTML format. There is no downloadable file or PDF version. The Physiology editorial board was not involved in the peer review process.