Citations

Abstract Introduction The mitochondrial transporter ABCB7 is essential for exporting iron-sulfur (Fe-S) clusters, a function known to be critical in B cells. This study was conducted to investigate the broader, previously unknown roles of ABCB7 in regulating the overall lymphocyte development and homeostasis. Methods The study utilized conditional knockout (cKO) mouse models (CD2-iCre and Mb1-Cre) to create a specific deficiency of ABCB7 in certain immune populations. To determine if the observed effects were due to ABCB7 deletion in myeloid cells, two further models (CD2i-Cre ABCB7 cKO/C/EBPα and CD2-iCre LSL TMT ABCB7 cKO) were developed. The effects of blocking the cytokine G-CSF were also examined to understand its role in the observed myelopoiesis. Results ABCB7 deficiency was found to dramatically impair erythropoiesis while simultaneously driving emergency myelopoiesis. We confirmed that the myeloid expansion was not a direct result of ABCB7 loss in myeloid cells. A significant autoimmune phenotype also developed, characterized by hyperactivated T cells and a sharp decrease in peripheral regulatory T cells (Tregs). This Treg instability was linked to decreased thymic expression of key stability genes (like CD28 and PD-1) and reduced O-GlcNAc modification in T cells, a process crucial for maintaining Treg lineage. Conclusion The findings establish ABCB7 as a pivotal regulator of hematopoietic balance, linking mitochondrial function to both myeloid expansion and Treg stability. Funding Source T32AI170478 Topic Categories Hematopoiesis and Immune System Development (HEM)

Exercise and physical activity are recognized as essential tools to optimize fitness and longevity, improve overall health, and reduce the risk of cardiovascular disease and other major comorbidities. However, there are inherent risks associated with participation in sports and exercise, regardless of the level of competition or skill required. As such, there is a need for cardiologists to understand the unique aspects of competitive and recreational athletics, as well as sport and exercise science, as it relates to overall heart health and cardiovascular risk. In this article, we provide an overview of the essential aspects of sports and exercise cardiology. We describe the roles and responsibilities of a sports and exercise cardiologist as a member of a comprehensive team of experts who provide care of athletes at all levels of sport, emphasize the importance of risk stratification and prevention of sudden cardiac arrest, the role of exercise for maintaining and optimizing overall health in the general population, describe the growing field of sports electrophysiology and also discuss unique aspects of sports cardiology applied to environmental health and care of the tactical athlete. Knowledge gaps and directions for future clinical and research investigation are reviewed.

Abstract Background Rare pediatric and young adult brain tumors pose major diagnostic and therapeutic challenges due to limited evidence and scattered expertise. The International Rare Brain Tumor Board was established to enable multidisciplinary case review, shared learning, and collaborative decision support. Methods Launched in February 2025, the Rare Brain Tumor Board is a monthly collaborative initiative led by Children’s National Hospital and the National Institutes of Health (NIH). Close partnership with the European Pediatric Rare CNS Tumor Board enhances transatlantic exchange and alignment of diagnostic and treatment recommendations. De-identified cases are presented with clinical history, neuroimaging, histopathology, and molecular profiling, including DNA methylation classification, available for the majority of cases. Sessions are structured to support integrated diagnosis and evidence-informed management recommendations through multidisciplinary discussion (neuropathology, neuroradiology, neurosurgery, radiation oncology, and pediatric as well as adult neuro-oncology). Findings Since its inception, 12 sessions have been held averaging 138 participants per session, reviewing a total of 32 cases (mean 3 cases/session; range 1–4) from 7 different countries and 3 different continents. Entities reviewed include DICER1-intracranial sarcoma (n = 5), astroblastoma (n = 4), FOXR2-activated neuroblastoma (n = 4), CNS tumors with BCOR internal tandem duplication (n = 3) and, BCOR-fused tumors (n = 3), CIC-rearranged-sarcoma (n = 3), intracranial mesenchymal tumor FET::CREB fusion positive (n = 3), MN1::PATZ1 fusion tumors (n = 2), undifferentiated sarcoma (n = 2), PLAG1-fusion tumor (n = 1), medullomyoblastoma (n = 1), and EZHIP-altered diffuse midline glioma (DMG) (n = 1). Multidisciplinary review has supported diagnostic clarification, strengthened familiarity with ultra-rare entities, and informed real-world treatment discussions in settings where prospective data are limited. Discussions have also increased awareness of rare brain tumor registries and opportunities for systematic case capture. Conclusion An international multidisciplinary rare brain tumor board is a feasible, scalable model to advance integrated diagnosis and collaborative management of ultra-rare pediatric and young adult brain tumors, while building a shared knowledge base across institutions.

Background: Real-time intraoperative discrimination of malignant tissue during pediatric solid tumor resection is limited, constraining margin optimization; the utility of indocyanine green (ICG) fluorescence in this population remains incompletely defined. Study Design: Prospective, observational, multi-institutional study (2019–2023) of pediatric, adolescent, and young adult patients undergoing resection of intra-abdominal solid malignancies following preoperative ICG administration. The primary endpoint was diagnostic accuracy of ICG fluorescence for tumor-containing specimens; secondary endpoints included association with margin status and surgeon-perceived intraoperative benefit. Results: Forty-three operations in 42 patients yielded 55 specimens, of which 47 (85%) were malignant. Diagnostic performance was highest in hepatic tumors (sensitivity 83%, positive predictive value 83%) and lower in adrenal and heterogeneous tumor types. ICG avidity was not associated with improved negative margin rates (86% vs 75%, p=0.47). Surgeons reported intraoperative benefit in 67% of cases, most commonly improved visualization. No ICG-related adverse events occurred. Conclusions: ICG fluorescence provides reliable tumor identification in hepatic malignancies but does not correlate with margin-negative resection, indicating limited utility for margin guidance. These data support tumor-specific application and further investigation of optimized fluorescence strategies, including dosing, timing, and alternative fluorophores, in pediatric oncologic surgery.

PURPOSE In immunoglobulin light chain (AL) amyloidosis, amyloid fibrils cause organ dysfunction. Anselamimab, a monoclonal antibody, selectively binds to amyloid fibrils, accelerating their clearance. METHODS Newly diagnosed patients with European modification of Mayo 2004 stage IIIa or IIIb AL amyloidosis were randomly assigned to receive anselamimab or placebo with cyclophosphamide, bortezomib, and dexamethasone (with or without daratumumab). The primary end point was a hierarchical composite of time to all-cause mortality (ACM) and frequency of cardiovascular hospitalizations (CVHs), analyzed using the Finkelstein-Schoenfeld test and win ratio estimation. RESULTS Among 406 randomly assigned patients, the primary end point win ratio for anselamimab versus placebo was 1.11 (95% CI, 0.83, 1.50; P = .332) and the hazard ratio (HR) for ACM was 0.80 (95% CI, 0.57, 1.13; P = .290). CVH rates in the anselamimab and placebo groups were 0.59 (95% CI, 0.42, 0.83) and 0.89 (95% CI, 0.55, 1.43), respectively ( P = .145). Among patients with kappa isotype (n = 72), the win ratio was 2.06 (95% CI, 0.98, 4.31; P = .100) and anselamimab reduced ACM by 62% versus placebo (HR, 0.38; 95% CI, 0.17 to 0.86; nominal P = .012), and CVH by 71% (IRR, 0.29; 95% CI, 0.10 to 0.87; nominal P = .028) with improvements in Kansas City Cardiomyopathy Questionnaire-Overall Score. There was no clinical benefit observed in the lambda population. Anselamimab was generally well-tolerated; safety data were comparable between treatment arms overall. CONCLUSION Treatment with anselamimab, an antifibril antibody used alongside antiplasma cell dyscrasia therapy, while not meeting the primary end point in the overall population, significantly improved ACM and CVH in patients with kappa AL, potentially offering a new therapeutic option for this isotype.

TPS7101 Background: Patients with high-risk CLL/SLL not achieving a complete response (CR) after ≥ 12 months of BTK inhibitor (BTKi) monotherapy remain at risk for early progression due to residual disease and BTKi resistance. A BCL-2 inhibitor (BCL-2i) introduces a complementary, BCR-independent apoptotic mechanism that may deepen responses and prolong progression-free survival (PFS). Lisaftoclax, a selective oral BCL-2i with a short half-life (4-6 h), enables once-daily dosing and is approved in China as second-line CLL therapy. Lisaftoclax monotherapy has demonstrated overall response rates (ORRs) of 67% in relapsed/refractory CLL and 62.5% in BTKi-refractory disease, including del(17p)/ TP53 -mutated cases. Lisaftoclax combined with acalabrutinib achieved ORRs >97% with favorable tolerability. This study evaluates whether lisaftoclax plus BTKi (acalabrutinib, zanubrutinib, or ibrutinib) improves PFS and/or overall survival (OS) (vs continued BTKi monotherapy) in patients with CLL/SLL and residual disease after prolonged BTKi treatment. Methods: This study will enroll approximately 440 patients randomly allocated to receive lisaftoclax plus BTKi or BTKi alone. Eligible patients have CLL/SLL and, after ≥12 months of BTKi monotherapy (lines 1-3), have achieved neither CR nor progressive disease (PD). Randomization is stratified by del(17p)/ TP53 status. Key inclusion criteria include age ≥18 years, ECOG PS 0-2, and residual disease with either high-risk features (del(17p)/ TP53 mutation, unmutated IGHV , or complex karyotype [≥5 abnormalities]), or measurable residual disease with lymph nodes ≥2.5 cm in the absence of high-risk features. Exclusion criteria include prior BCL-2i therapy or Richter transformation. Patients in the investigational arm will undergo a 5-day oral lisaftoclax ramp-up to 400 mg once daily plus physician's choice of BTKi in 28-day cycles until progression or toxicity. Control patients continue their current BTKi monotherapy. Safety and disease assessments (CT/MRI) will occur regularly. The primary endpoint is PFS by independent review committee (iwCLL 2018); key secondary endpoint OS; and other secondary endpoints, PFS by investigator, ORR, duration of response, MRD negativity, and safety. Enrollment is ongoing across 126 sites in 18 countries (ClinicalTrials.gov ID: NCT06104566). Clinical trial information: NCT06104566 .

e16335 Background: Splanchnic vein thrombosis (SVT) is a rare but serious complication in gastrointestinal (GI) cancer patients. This study investigated its features and outcomes in U.S. hospitalizations. Methods: Hospitalizations (≥18 years old) with a GI malignancy (ICD-10-CM C15–C26) and portal vein thrombosis (PVT) (I81), hepatic vein thrombosis (HVT) (I82.0), or mesenteric/splenic vein thrombosis (MSVT) (I82.890 + K55) in any of the 40 diagnosis fields were found in 2022 National Inpatient Sample. Exclusions: non-GI cancers (C00-C14, C27-C96), thrombophilia (D68.5, D68.6, D45, D47.1, D59.5), or cirrhosis (K74, K70.3). Demographics and outcomes (in-hospital mortality, length of stay [LOS], and total hospital charges [TOTCHG]) were compared between SVT and non-SVT groups using unweighted descriptive statistics (medians, IQRs), χ², and Mann-Whitney U tests. Multivariable regression of mortality, LOS, and TOTCHG were adjusted for age, sex, race, income quartile, insurance type, hospital region and bed size, and comorbidity burden (elixsum). Stata 17.0 was used. Results: Among 51,940 GI cancer hospitalizations (mean age 68.37 ± 12.79 years; 44.46% female), 833 (1.60%) had SVT. SVT group was younger (66.60 ± 11.76 vs. 68.40 ± 12.80 years; p < 0.001). Sex distribution was similar (58.34% vs. 55.50% male; p = 0.101). Common cancers in SVT: liver (n=427; 51.26%), pancreas (n=310; 37.21%), and colorectal (n=42; 5.04%). SVT prevalence was highest in liver (7.10%), pancreatic (3.14%), gallbladder (2.65%), and biliary (2.13%) cancers. PVT was the predominant subtype (n=788; 94.60%), followed by HVT (n=21; 2.52%), MSVT (n=4; 0.48%), and multiple SVT sites (n=20; 2.40%). SVT subtype distribution was: PVT (n=788; 94.60%), HVT (n=21; 2.52%), MSVT (n=4; 0.48%), and multiple sites (n=20; 2.40%). SVT had longer median LOS (5 [3–10] vs. 4 [3–8] days; z = -6.666, p < 0.001), similar median charges ($65,053 [I33,560–130,026] vs. $66,433 [35,897–121,038]; z = -0.76, p = 0.447), and higher mortality (9.48% vs. 4.41%; χ² = 49.042, p < 0.001). In adjusted analyses, SVT had higher mortality (aOR = 2.23, 95% CI 1.74–2.85, p < 0.001), longer LOS by 1.50 days (95% CI 0.99–2.02, p < 0.001), and 14.63% higher TOTCHG (coefficient 0.136, 95% CI 0.051–0.222, p = 0.002). Conclusions: SVT affects ~1.6% of GI cancer hospitalizations, is most prevalent in liver cancer, and associated with longer stays and higher mortality, underscoring the need for proactive monitoring. Multivariable regression analyses of SVT on clinical outcomes (unweighted sample). Outcome SVT Effect 95% CI P-value Interpretation In-hospital mortality OR 2.23 1.74–2.85 <0.001 SVT doubles odds of in-hospital death Length of stay (days) +1.50 0.99–2.02 <0.001 SVT associated with ~1.5 extra hospital days Total hospital charges ($) +0.136 (log scale) 0.051–0.222 0.002 SVT increases hospital costs by ~14.63%

7501 Background: AL amyloidosis is a plasma cell dyscrasia (PCD) characterized by κ or λ Ig light chain amyloid fibrils that deposit in vital organs. Anselamimab is an investigational mAb designed to complement anti-PCD therapy through accelerated removal of amyloid fibrils. Cardiac Amyloid Reaching for Extended Survival (CARES) studies (NCT04512235 and NCT04504825) investigated the efficacy and safety of anselamimab compared with placebo, in addition to anti-PCD therapy. Methods: Alongside anti-PCD therapy with CyBorD (daratumumab was permitted) newly diagnosed patients with European modification of Mayo stage IIIa or IIIb AL amyloidosis were randomized 2:1 to receive anselamimab (1000 mg/m 2 ) or placebo (normal saline) IV every 7 days for 4 weeks followed by every 14 days for the remainder of the blinded study (18 months after the last participant enrolled). The primary endpoint was a hierarchical combination of time to all-cause mortality (ACM) and frequency of adjudicated cardiovascular hospitalizations (CVH) using the Finkelstein-Schoenfeld test and win-ratio in the combined study population. Subgroup analysis by involved κ or λ free light chain (iFLC) was prespecified. Results: 271 patients were randomized to receive anselamimab and 135 placebo. Baseline characteristics were similar between treatment arms. The median duration of treatment was 21.4 months and 21.1 in the anselamimab and placebo arms, respectively. Daratumumab was used in 79.3% and 83.7% of the anselamimab and placebo arms, respectively. Results of the primary efficacy analyses are shown in the table. Anselamimab-treated patients with κ iFLC had a 62% reduction in ACM (HR = 0.38; 95% CI, 0.17, 0.86; nominal P = 0.012) and a 71% reduction in risk for CVH (estimated CVH rate ratio = 0.29; 95% CI, 0.10, 0.87; nominal P = 0.028). Patients with λ iFLC had a 10% reduction in risk for CVH; none in ACM. Safety data were comparable between both treatment arms. In anselamimab-treated patients, safety findings were similar between κ subgroup and full population. Conclusions: Anselamimab, a κ light chain–directed anti-fibril monoclonal antibody used alongside standard of care chemotherapy, offers a first-in-class, new therapeutic option for patients with newly diagnosed κ AL amyloidosis. Clinical trial information: NCT04512235 and NCT04504825 . Summary of primary efficacy endpoints. Endpoint Overall κ Isotype λ Isotype Anselamimab (N=271) Placebo (N=135) P -value Anselamimab (N=48) Placebo (N=24) P -value Anselamimab (N=219) Placebo (N=109) P -value ACM and CVH win ratio (95% CI) 1.1 (0.8, 1.5) 0.332 2.06 (0.98, 4.31) 0.100 0.9 (0.6, 1.3) 0.848 ACM n (%) 90 (33.2) 52 (38.5) 15 (31.3) 14 (58.3) 73 (33.3) 37 (33.9) HR (95% CI) 0.8 (0.6, 1.1) 0.290 0.38 (0.2, 0.9) 0.012 1.0 (0.7, 1.5) 0.647 CVH Frequency/year (95% CI) 0.6 (0.4, 0.8) 0.9 (0.6, 1.4) 0.145 0.41 (0.2, 0.8) 1.4 (0.6, 3.4) 0.028 0.7 (0.4, 1.0) 0.8 (0.4, 1.3) 0.664 Incidence risk ratio (95% CI) 0.7 (0.4, 1.2) 0.29 (0.1, 0.9) 0.9 (0.5, 1.7)