Citations

Abstract Background: Pembrolizumab has been increasingly used off label for recurrent gliomas, yet biomarkers predicting response are poorly defined. Gliomas exhibit substantial molecular heterogeneity across Glioblastoma, IDH-wildtype (GBM), Astrocytoma, IDH-Mutant (A-IDHm), and Oligodendroglioma, 1p/19q co-deleted (OLIGO), which may influence immunotherapy efficacy. This study aimed to identify molecular predictors of progression-free survival (PFS) in recurrent glioma patients treated with pembrolizumab. Methods: Adults ≥18 years with recurrent glioma receiving ≥2 cycles of pembrolizumab between 2014 - 2024 were retrospectively identified across Mayo Clinic. Next-generation sequencing (NGS) reports were reviewed and archival tumor tissue resected prior to pembrolizumab initiation was analyzed when available. Comprehensive molecular profiling was performed using the Mayo Clinic Solid Tumor Panel which employs the Illumina Tru-Sight Oncology 500 High-Throughput NGS assay. Progression was assessed using RANO 2.0 criteria. Genomic alterations (clinically relevant sequences and/or copy-number variants) were evaluated using the Kaplan-Meier method, with differences in PFS compared using the log-rank test. Results: Thirty-three patients were included [median (range) age: 44.0 (21-76) years; 63.6% male]. The interval between tumor tissue sampling and pembrolizumab initiation was 9.9 (0.9-176.1) months, and median treatment duration was 2.8 (1.4-10.4) months. Median PFS for the overall cohort was 2.4 (0.8-15.2) months, and median overall survival from pembrolizumab initiation was 6.9 (0.9-48.2) months. Patients with OLIGO (n=8) had a longer PFS [4.6 (1.9-15.2) months] than either A-IDHm [n=11; PFS 2.1 (1.1-4.4) months] or GBM [n=14; PFS 2.3 (0.8-9.2) months]. Within OLIGO, CDKN2A/B heterozygous deletion (n=3) predicted a shorter PFS (3.9 vs 10.9 months; p=0.0462), while in A-IDHm, FANC mutation (n=2) was associated with a longer PFS (4.17 vs 1.61 months; p=0.0224). No significant associations with PFS were observed for other altered genes or pathways evaluated, including but not limited to Tumor Mutational Burden, EGFR, RB1, TP53, FUBP1, NF 1 or 2, PTEN, PDGFRA, PIK3CA, PIK3R1, CDK4, KRAS, MLH1, MLH2, MSH6 genomic alterations or CDKN2A/B homozygous deletion (all p>0.05). Conclusions: Pembrolizumab shows limited overall efficacy in recurrent gliomas, however, exploratory analyses identified several subtype-specific genomic alterations that may correlate with PFS. These hypothesis-generating findings highlight the potential influence of underlying tumor biology on immunotherapy response and warrant further validation in larger, prospective cohorts. Citation Format: Shameel Shafqat, Muhammad Asad Maqbool, Hussam Al Kateb, Terry C. Burns, Jian L. Campian, Shannon P. Fortin Ensign, Evanthia Galanis, Julie E. Hammack, Cristaine M. Ida, Mitch L. Klebig, Timothy J. Kaufmann, Autumn C. Moon, Maciej M. Mrugala, Bryan J. Neth, Alyx B. aPorter, Michael W. Ruff, Ugur T. Sener, Wendy J. Sherman, Joon H. Uhm, Rachael A. Vaubel, Sani H. Kizilbash. Molecular correlates of progression-free survival in recurrent gliomas treated with pembrolizumab [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2026; Part 1 (Regular Abstracts); 2026 Apr 17-22; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2026;86(7 Suppl):Abstract nr 5253.

Abstract Introduction: Detectable circulating tumor DNA (ctDNA) is associated with inferior outcomes in Ewing sarcoma (ES); however, ctDNA clears in nearly all patients within 2 of the 6 chemotherapy cycles before radiotherapy (RT) or surgery. Given a 3-year EFS of 37% on AEWS 1221 (metastatic) and 5-year EFS of 78% on AEWS 1031 (localized), current ctDNA testing fails to predict most relapses. Extracellular vesicles (EVs) are microscopic particles studied as a biomarker in multiple cancer types. We hope to improve the sensitivity of ctDNA in ES and provide the first application of EVs in ES. Methods: cfDNA was isolated from 1mL plasma, quantified by Qubit, and sequenced as NEBNext Enzymatic Methyl-seq v2 libraries. We performed a systematic unsupervised clustering analysis of 27 ES plasma cfDNA profiles using 4 differentially methylated regions (DMR) subsets (63 strong DMRs, top 30, top 15, and 10 promoter-proximal loci), 3 clustering algorithms (k-means, Ward hierarchical, PAM), and k=2-5 clusters, testing associations with tumor burden and progression. EV analysis involved antibody detection against ES surface markers, including LINGO1, ENPP1, CDH11, and CD99. Concentrations of EVs were determined by standardized and calibrated high-resolution flow cytometry then analyzed with custom-built software to automatically determine and apply gates. Samples were de-identified, randomly coded, and run in triplicates. The senior research technologist responsible for EV analysis was blinded to patient information and clinical data. Results: EV analysis included 36 pre-RT samples from 16 metastatic and 20 localized ES patients from a prospectively maintained biobank, with 27 pre-RT samples in the cfDNA analysis and 19 healthy donor (HD) samples. 35 of 36 patients had chemotherapy before sample collection. cfDNA concentrations were markedly elevated in ES patients compared with HD (24.4 vs 4.6 ng/mL, p<0.0001), and 74% of ES samples exceeded the HD 95th-percentile detectability threshold (7.0 ng/mL). Across clustering configurations, ES cfDNA profiles consistently exhibited reproducible methylation substructure. One configuration (PAM clustering, k = 5, 63 strong DMRs) showed a modest but permutation-supported association with primary tumor size (nominal p ≈ 0.04; empirical p ≈ 0.03-0.04). ES samples had increased EV concentration compared to HD (p<0.001), with AUC 0.988 for distinguishing between ES and HD ENPP1 (p<0.0001). The highest ENPP1 EV values were in patients with large primary tumors (>8 cm vs. ≤ 8cm) and metastatic disease (p=0.066). Conclusions: cfDNA- and EV-based liquid biopsy provide encouraging signals for high ES detectability pre-RT. We also show the first study of EVs as a novel biomarker in ES, which may provide complementary information to ctDNA. Multimodal liquid biopsy in ES may identify candidate patients for systemic or local therapy escalation and facilitate personalized care. Citation Format: Roman O. Kowalchuk, Lilli J. Greiner, Yohan Kim, Rubia Noori, Jeffrey Szymanski, William S. Harmsen, Pradeep S. Chauhan, Adam C. Amundson, Andrea M. McMahon, Peter J. Schoettler, Wendy A. Allen-Rhoades, Stephanie F. Polites, Peter S. Rose, Kelly M. Bailey, Linda M. McAllister-Lucas, Anita Mahajan, Fabrice Lucien-Matteoni, Nadia N. Laack, Aadel A. Chaudhuri. Multimodal liquid biopsy of Ewing sarcoma reveals high sensitivity prior to radiotherapy [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2026; Part 1 (Regular Abstracts); 2026 Apr 17-22; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2026;86(7 Suppl):Abstract nr 1149.

Abstract Background: Small cell lung cancer (SCLC) remains an aggressive malignancy with limited treatment options and a 5-year survival rate under 10%. Delta-like ligand 3 (DLL3), expressed in >85% of SCLC but absent from normal tissue, represents an attractive therapeutic target. Existing DLL3-directed antibody-drug conjugates suffer from poor payload stability and limited tumor penetration. To overcome these limitations, we engineered a DLL3-targeted nano-immunoconjugate (NIC) of SN38, the active metabolite of irinotecan, using an albumin-based nanoscaffold. Methods: SN38 was encapsulated in a human serum albumin (HSA) matrix and non-covalently coated with a recombinant anti-DLL3 monoclonal antibody to yield DLL3-SN38-NIC. Stable conjugation was confirmed by HSA-IgG interactions and zeta-potential shift. Binding kinetics were evaluated using Biacore surface plasmon resonance (SPR) and Octet bio-layer interferometry (BLI) employing AHC biosensors to determine DLL3-antibody affinity and specificity. Cytotoxicity was assessed using IncuCyte live-cell imaging across five SCLC cell lines (DMS454, SHP77, NCI-H82, NCI-H889, and NCI-H211) with varying DLL3 expression. Results: DLL3-SN38-NIC retained high-affinity DLL3 binding (KD ≈ 3 × 10-10 M) and demonstrated potent cytotoxicity in SCLC cell lines. NIC formation did not reduce cytotoxic activity compared with free SN38, confirming preserved potency. Cytotoxicity trends were consistent across lines with variable DLL3 expression, and DLL3 antibody alone exhibited negligible cytotoxicity. These findings confirm that nano-immunoconjugate formation maintains drug activity and DLL3 binding; additional in-vivo studies are underway to evaluate pharmacokinetics and tumor selectivity. Conclusions: Albumin-based DLL3-SN38-NICs represent a novel nano-oncologic platform that preserves SN38 potency and achieves high-affinity DLL3 engagement. Ongoing studies will assess in-vivo selectivity, biodistribution, and therapeutic potential in DLL3-positive SCLC and other neuroendocrine malignancies. Citation Format: Mohamed Shanshal, Lin Yang, Liyi Geng, Wendy Nevala, Aaron S. Mansfield, Bharath Wootla, Konstantinos Leventakos, Kyle Korshavn, Svetomir N. Markovic. Albumin-based DLL3-targeted nano-immunoconjugates of SN38 preserve potency and demonstrate high-affinity DLL3 binding in small cell lung cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2026; Part 1 (Regular Abstracts); 2026 Apr 17-22; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2026;86(7 Suppl):Abstract nr 449.

Summary Evidence for an association between insulin‐like growth factors (IGF) and multiple myeloma (MM) is inconsistent. We examined total IGF‐I concentrations and risk of MM by combining baseline serological data among UK Biobank participants ( n = 444 187; 732 incident MM) with a two‐sample Mendelian randomisation (MR) analysis using identified genetic variants associated with circulating total IGF‐I and IGF‐binding protein 3 (IGFBP‐3) in the InterLymph consortium (2434 MM and their 2567 controls). Finally, additional lymphoid neoplasm (LN) subtypes were included for comparison with the main hypothesis. Circulating IGF‐I level was positively associated with MM risk Hazard ratio‐HR‐per one standard deviation‐SD‐increase (HR 1‐SD = 1.11, 95% confidence interval [CI]: 1.01–1.22; p ‐value = 0.03), especially closer to diagnosis. Genetically inferred IGF‐I levels were associated with increased MM risk (odds ratio [OR] = 1.27, 95% CI: 1.05–1.54) but not with any other LNs. Genetically inferred IGFBP‐3 levels showed no associations with any LN evaluated. Corroborating previous findings, in a secondary analysis, IGF‐I levels were associated with the risk of chronic lymphocytic leukaemia/small lymphocytic lymphoma (CLL/SLL) in males with higher body mass index (HR 1‐SD in obese male = 1.36, 95% CI: 1.14–1.61). Our serological and MR analyses suggest a contributing role of IGF‐I in the susceptibility of MM; the CLL/SLL findings warrant further investigation considering sex‐specific adiposity.

ABSTRACT Background Decision‐making (DM) dynamics between adolescents and young adults (AYAs) with cancer, parents, and oncologists remain underexplored in diverse populations. We examined cancer treatment DM preferences among an ethnically and socioeconomically diverse group of AYAs and their parents. Procedure We surveyed AYAs with cancer ( n = 75) and their parents ( n = 52) participating in the Texas KidsCanSeq study. Among AYA‐parent pairs, we compared preferred and actual treatment DM roles. We explored associations among DM roles, having pediatric‐to‐adult care transition discussions, and clinical and sociodemographic characteristics. We report AYAs’ and parents’ preferences for involvement in shared decision‐making (SDM) with oncologists about cancer treatment. Results AYAs’ DM role preferences varied: 44% preferred to equally share DM with parents, 31% preferred AYA‐led DM, and 25% preferred parent‐led DM. Parents who preferred parent‐led DM had younger AYAs than parents who preferred equally shared DM ( p = 0.011). For actual DM, 48% of AYAs reported DM was equally shared, 24% reported DM was AYA‐led, and 28% reported DM was parent‐led. Most AYAs had their preferred role (73%). AYAs’ actual role did not significantly differ from their own or their parents’ preferences (both p > 0.05). Approximately half of AYAs reported recent pediatric‐to‐adult care transition discussions. AYAs’ DM preferences and participation in transition discussions did not significantly differ along clinical or sociodemographic characteristics (all p > 0.05). AYAs and parents perceived high importance across all aspects of SDM with oncologists. Conclusion In this diverse study population, AYAs desired engagement in treatment DM and SDM. Although specific role preferences varied, opportunities existed to increase discussion around pediatric‐to‐adult care transition.

ABSTRACT Background and Aims Women now comprise over half of US medical school matriculants yet remain underrepresented in academic leadership, including emergency medicine (EM). Leadership training within medical education is variable, particularly in communication, conflict management, negotiation, and operations. Concurrently, large language models (LLMs) are emerging as accessible tools to support leadership skill development. This study aimed to develop and evaluate an AI‐augmented leadership skills workshop designed to address the leadership gap for women in academic emergency medicine. Materials and Methods The Academy for Women in Academic Emergency Medicine (AWAEM) developed and piloted a leadership development workshop at the 2025 Society for Academic Emergency Medicine Annual Meeting. The curriculum integrated evidence‐based leadership frameworks with experiential small‐group learning and structured demonstrations of LLM use. Educational strategies included brief didactics, reflection on lived leadership challenges, peer discussion, and guided LLM‐supported simulation of leadership conversations. Pre‐workshop and postworkshop surveys and qualitative feedback were collected to assess participant confidence and perceived utility. Results Participants demonstrated increased confidence in navigating power‐differential conversations and initiating negotiations following the workshop. There was greater reported intent to apply leadership frameworks and to utilize LLMs for leadership‐related tasks. Qualitative feedback highlighted themes of empowerment, practical applicability, and the importance of a psychologically safe, gender‐informed learning environment. Participants identified LLMs as a novel and accessible adjunct to traditional leadership development resources. Discussion and Conclusions An AI‐augmented, experiential leadership workshop is a feasible and scalable approach to addressing persistent leadership development gaps for women in academic emergency medicine. Integrating LLM‐supported practice with established leadership frameworks may enhance learner confidence and engagement. This model offers a practical strategy to support leadership skills for women physicians needed to navigate systemic barriers and advance into leadership roles.

Abstract The recent FDA approval of the first T-cell receptor–engineered (TCR) T-cell cancer therapy has solidified the treatment as a viable therapeutic strategy. However, only a fraction of patients who received this treatment achieved substantial and long-lasting responses, highlighting the need to understand the molecular underpinnings of these responses and develop more effective strategies to improve this therapy. Previous research has demonstrated that the activation of myeloid differentiation primary response 88 (MyD88) signaling in tumor-specific T cells functions as a robust costimulatory signaling pathway that promotes effective antitumor T-cell responses. In this study, we developed a strategy for improving TCR T-cell therapies by creating a synthetic TCR in which the intracellular domain of CD3ζ and a modified MyD88 are appended to the β-chain of a tumor-reactive TCR. The β:CD3ζ:MyD88 TCR activated MyD88 signaling in a tumor antigen/TCR-specific manner, and β:CD3ζ:MyD88 TCR T cells exhibited enhanced functionality and a reduced propensity to become exhausted. Furthermore, MyD88 signaling promoted T-cell persistence and expansion in vitro. In vivo, tumor-infiltrating β:CD3ζ:MyD88 TCR T cells skewed the immunosuppressive tumor microenvironment toward a less immunosuppressive state. Finally, β:CD3ζ:MyD88 TCR T cells substantially delayed tumor growth kinetics in a melanoma model. These findings introduce an approach for improving TCR-dependent T-cell responses by directly appending signaling domains to the full-length TCR and exemplify the utility of activating MyD88 signaling in tumor-specific T cells. Significance: A chimeric β:CD3ζ:MyD88 TCR reduces exhaustion and improves antitumor T-cell responses, overcoming the limited efficacy of current TCR-engineered T-cell cancer therapies.

ABSTRACT Background Primary lateral sclerosis (PLS) is an ultrarare upper motor neuron syndrome with a prognosis unique from classical ALS. The study of PLS is complicated by its rarity and the difficulty distinguishing PLS from ALS. We present data from a 1‐year prospective follow‐up study on PLS and efforts to distinguish it from ALS. Methods Seventy‐six PLS participants enrolled in this prospective natural history study. EMG studies, blood neurofilament light chain levels (NfLs), and demographic characteristics were obtained at baseline. At 1‐year follow‐up, repeat EMG studies were conducted to determine which participants fulfilled criteria for ALS. Baseline characteristics were then compared to determine features that predict reclassification. Results Seventy participants completed 1‐year follow‐up. Five of the 70 were reclassified to ALS (7.1%). Those reclassified had higher trends in baseline blood NfL levels (91.4 vs. 34.0 pg/mL, p = 0.13) and shorter symptom duration (39 vs. 69 months in the PLS group, p = 0.15). Reclassification was noted in both probable and definite PLS participants. All cases with a symptomatic duration of less than 2 years retained the PLS phenotype (5 of 5). NfL levels over 90 pg/mL predicted reclassification with 94% specificity and 60% sensitivity. No other features predicted reclassification to ALS. Conclusions In our population, reclassification of PLS to ALS occurred at a low frequency at 1 year follow‐up (7.1%). Baseline NfL was the strongest predictor in differentiating UMN dominant ALS from PLS at 1‐year follow‐up. Based on our data, we propose EMG and NfL criteria for enrollment in future PLS trials.

Abstract Rare Mendelian disorders affect 300-400 million people globally. Although genetic testing has become widely adopted, gene-specific evidence for tailored variant interpretation remains scattered across resources. We present Gene Portals, a framework for gene-centered multimodal knowledge bases that co-localize expert-harmonized clinical data, functional assays, population variation, structural annotations and gene-specific ACMG/AMP specifications within a single resource. A modular interface integrates this unified evidence with VCEP-refined ACMG specifications to enable automated gene-specific variant classification, infer molecular mechanisms, and support cross-gene analyses. We demonstrate the framework’s utility across five Gene portals spanning eleven neurodevelopmental disorder-associated genes, integrating data from 4,423 individuals with 2,838 unique variants, 36,149 ClinVar submissions, and 1,044 expert-curated molecular readouts. By organizing evidence that is otherwise dispersed across multiple sources into a unified, queryable framework, the SCN, GRIN, CACNA1A, SATB2 and SLC6A1 Gene Portals became widely used community resources and provide an extensible template for standardized rare-disease variant interpretation and mechanism-aware discovery.