Citations

Abstract Background: The goal of this study is to evaluate the immunomodulatory effects of daratumumab-(anti-CD38)-based therapy on fHRMM patients enrolled in the MMRF sponsored MyDRUG umbrella clinical trial (NCT03732703) over the duration of therapy and to correlate immune changes with patient response. Methods: fHRMM who had received 1-3 prior therapies (exposed to at least one proteasome inhibitor and an IMiD) were given a combination of daratumumab (D), ixazomib (I), pomalidomide (P) and dexamethasone (d) (D-IPd) quadruplet therapy. Bone marrow (BM) aspirates were then collected from patients prior to therapy (BL), after 2 cycles (EOC2), after 4 cycles (EOC4) of the quadruplet therapy and at the end of treatment or disease progression (EOT). Immune and tumor fractions were enriched by CD138 selection. Here, CD138- bone marrow mononuclear cells were isolated and transcriptionally profiled by scRNAseq and scTCRseq. Results: Single-cell RNA and TCR profiles were generated from ∼90,000 cells across 41 samples from 16 subjects. scRNAseq identified CD3+ T cells, NK cells, classical and non-classical monocytes and B cells. CD8+ T cells were further resolved into their subsets including precursor (TPEX) and terminally exhausted T cells (TEX) within the bone marrow microenvironment. Within the CD8+ T cell compartment, an expansion of the effector memory (TEM) cell population was observed following 2-cycles of therapy (EOC2). However, this TEM expansion was not sustained at timepoint EOC4. Towards the end of therapy, enrichment of precursors to exhausted and terminal dysfunctional effector memory cells (TEMRA) was observed. Subjects with partial (PR), very good partial (VGPR) and complete (CR) best overall responses showed an initial increase in TEM cells followed by a slow expansion of TEX and TEMRA cells over time. Longitudinal tracking of T cell clonality showed preferential progressive expansion of TEMRA cells after the therapy. We mapped hyperexpanded (more than 16 copies) clonotypes, presumed to be tumor-reactive, to various CD8+ T cell subsets. These hyperexpanded clonotypes mapped to the TEMRA, TEX and TEM CD8+ T cells. Analysis of TCR repertoires clonality and diversity also demonstrated a reduced richness and increased clonality of CD8+ TCRs in responders. Conclusions: Paired single cell RNA and TCR sequencing of BM T cells from RRMM patients receiving D-IPd quadruplet therapy revealed a selective expansion of clonotypic CD8+ T cells with a clonal replacement of BM exhausted clonotypes by dysfunctional circulating CD8+ T cells in responders over time. Citation Format: Chaitanya R. Acharya, Darwin D'souza, Reyka Jayasinghe, Mark Hamilton, Zhihong Zhihong, Seunghee Kim-Schulze, Hearn J. Cho, Shaji Kumar, George Mulligan. The immunomodulatory effects of daratumumab-based therapy on functional high-risk relapse/refractory multiple myeloma (fHRMM) patients enrolled in the MyDRUG trial [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2025; Part 1 (Regular Abstracts); 2025 Apr 25-30; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2025;85(8_Suppl_1):Abstract nr 5258.

Background: Anaplasma phagocytophilum is an emerging tick-borne zoonotic pathogen that typically causes mild infections, which are often successfully managed in outpatient settings. Immunosuppression associated with splenectomy is a well-documented risk factor for severe infections from pathogens such as Babesia microti and encapsulated bacteria. However, splenectomy has not previously been identified as a risk factor for severe anaplasmosis. Case Presentation: This report describes a rare case of severe anaplasmosis complicated by multiorgan failure in a patient who had undergone splenectomy several decades earlier. The clinical course was notable for pneumonia, acute respiratory distress syndrome, acute kidney injury, rhabdomyolysis, atrial fibrillation, and possible myocarditis. Despite the severity of the presentation, prompt initiation of doxycycline led to recovery, albeit with a significantly prolonged hospital stay. Conclusions: Patients with splenectomy might be more likely to develop a serious form of Anaplasmosis infection such as multiorgan failure. Clinicians in tick-borne endemic areas should be aware that non-specific symptoms can indicate anaplasmosis.

Background: Hypertrophic cardiomyopathy (HCM) is a genetic cardiomyopathy marked by increased left ventricular wall thickness, leading in some cases to left ventricular outflow tract (LVOT) obstruction, heart failure, and arrhythmias. Mavacamten, a selective allosteric inhibitor of cardiac myosin, has demonstrated benefits in improving hemodynamics and reducing LVOT obstruction. However, its impact on arrhythmic burden remains unclear, with reports of early atrial fibrillation (AF) risk contrasting with long-term reductions in arrhythmias. This study assesses the temporal patterns of Holter-detected arrhythmias in HCM patients treated with mavacamten. Methods: This retrospective study included HCM patients from three Mayo Clinic sites. Baseline demographic, clinical, and echocardiographic data were collected. Holter monitoring was performed at baseline, short-term (<6 months), and long-term (>6 months) follow-up. Arrhythmic events, including premature atrial contractions (PACs), premature ventricular contractions (PVCs), and supraventricular tachycardia (SVT), were analyzed using standardized rates per 24 h. Statistical comparisons utilized the Wilcoxon signed-rank test. Results: Twenty-seven patients (56% female, median age 66 years) were included. PACs, PVCs, and SVT duration transiently but not significantly increased at short-term follow-up but returned to baseline at long-term follow-up. No sustained or high-risk ventricular arrhythmias were observed. Conclusions: Mavacamten is associated with transient arrhythmic fluctuations early in treatment, followed by stabilization. These findings support its long-term electrophysiological safety and underscore the need for early rhythm monitoring. Further research should explore its role in arrhythmic risk stratification in HCM patients.

Abstract Background: Cholangiocarcinoma (CCA) is a diverse type of cancer. For several years, platinum-based chemotherapy (Gemcitabine and Cisplatin) has been the standard treatment and serves as the foundation for current immunotherapy combinations. The typical response rates are generally between 20% and 30%. In this study, we present the results of preclinical efficacy trials conducted on CCA patient-derived xenograft (PDX) models, correlating them with the baseline multiomics profiling of these models to identify molecular characteristics linked to treatment response. Methods: Tumor samples from twenty-eight CCA PDX were used to isolate RNA and protein to be included in multiomics analysis (Phosphoproteomics, Proteomics, and Transcriptomics). A subset of PDX models were treated with various doses of Gemcitabine and Cisplatin. The Median Efficacy Index (MEI) was calculated as the ratio of the difference in median of delta in tumor volume at the last day of the study between the treatment and the control arms divided by the median of delta in tumor volume of the control at the last day of the treatment (positive= growth, negative=inhibition, and 0=no efficacy). A Hierarchical All-Against-All algorithm was utilized to compare multiomics features to the MEI and pathway analysis completed for identified molecular features. Pathway enrichment was calculated using the KEGG database, and random-forest variable selection chose the pathways most influential in predicting sensitivity or resistance. Results: After conducting preclinical efficacy trials, the 11 tested CCA PDX models were classified into sensitive, moderately sensitive, and resistant models based on the MEI on each treatment arm. The top up-regulated genes were identified for Gemcitabine response (SRPK2, GLK2, and RIOK2) and Cisplatin response (NTRK1, PRPF4B, and SRPK2). The top up-regulated genes related to Gemcitabine resistance were NTRK1, PIP5K1C, and CSNK2A2, while those related to Cisplatin resistance were SRPK1, PRPF4B, and CSNK2A1. Downregulation of the anti-folate resistance pathway is a strong predictor of gemcitabine sensitivity, and the lysine degradation pathway is a strong predictor of cisplatin sensitivity. Conclusion: Multiomics signatures of cholangiocarcinoma can forecast responses to standard chemotherapy in preclinical models. New markers of resistance to Gemcitabine and Cisplatin were discovered, linked to NTRK1, SRPK1, and SRPK2. These resistance profiles will be tested using suitable targeted therapies on the resistant CCA patient-derived xenograft (PDX) models. Citation Format: Amro M. Abdelrahman, Danielle M. Carlson, Ellen L. Larson, Erik Jessen, Dong-Gi Mun, Isaac Lynch, Alessandro Fogliati, Stella Konadu Adjei Antwi, Aushinie Abeynayake, Akhilesh Pandey, Mark J. Truty, Gregory J. Gores, Rory L. Smoot. Baseline multiomics and chemotherapy efficacy in preclinical trials using patient-derived xenograft models of cholangiocarcinoma can reveal distinct signatures of chemotherapy response [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2025; Part 1 (Regular Abstracts); 2025 Apr 25-30; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2025;85(8_Suppl_1):Abstract nr 6762.

Abstract Glioblastoma is highly vascularized with increased perfusion and prognosis remains dismal, despite improved diagnosis and aggressive multimodal treatment. The current standard of care is maximal surgical resection when feasible, followed by adjuvant radiation with concurrent chemotherapy, temozolomide. However, treatment resistance and tumor recurrence pose a considerable challenge for stratifying patients for optimal treatment planning. Current radiological assessment of glioblastoma therapy response predominantly relies on morphological measures; that may not accurately capture early microscopic changes or therapeutic efficacy. We have developed and validated an advanced imaging method, Arterial Spin Labeling (ASL) MRI that enable noninvasive spatial assessment of the entire tumor. ASL-MRI uses water within the blood as an endogenous tracer and measures perfusion without the need for exogenous gadolinium-based contrast agent. The objective of this study was to investigate ASL measured quantitative perfusion after surgery to predict survival in glioblastoma patients undergoing the standard of care chemoradiation treatment. In this prospective, IRB-approved study, twenty-three adults with glioblastoma participated for longitudinal MRI. Progression-free survival (PFS) and overall survival (OS) were recorded for each patient. A baseline MRI scan was performed prior to chemoradiation treatment and after surgery utilizing a 3D ASL sequence. All structural images were co-registered to T1 post-contrast images. Tumor regions of interest (ROIs) such as enhancing tumor (ET), tumor core, whole tumor, and necrosis were manually segmented. Cerebral blood flow maps were calculated and mean perfusion values (MPV) within ET ROIs were extracted. Scatter plot of MPV and Kaplan-Meier graphs were generated using GraphPad Prism. Based on median survival of 420 days, patients were categorized into short (≤420 days) or long (&gt;420 days) survival. A threshold ASL measured perfusion value of 30 mL/100g/min distinguished survival groups; hyper-perfusion correlated with shorter OS, while hypo-perfusion linked to longer OS. The mean±SD of PFS and OS for patients with shorter survival were 119±42 days and 230±117 days respectively, while for longer survival were 624±285 and 726±210 days respectively, and the values were statistically different (P&lt;0.001for both). Kaplan-Meier curves showed significant OS and PFS differences (p&lt;0.015, Hazard Ratio=3.056). Our data indicate that ASL measured baseline perfusion, after surgery and before chemoradiation treatment can benefit in predicting survival and treatment stratification in glioblastoma patients. ASL measured perfusion can be performed during radiation treatment and could provide valuable information that can be incorporated into emerging treatment strategies such as adaptive radiation. Citation Format: Durga Udayakumar, Limin Zhou, Marco Pinho, Yiming Wang, Ben Wagner, Michael Youssef, Joseph Maldjian, Ananth Madhuranthakam. Noninvasive magnetic resonance imaging measured quantitative perfusion as predictive and prognostic biomarker in glioblastoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2025; Part 1 (Regular Abstracts); 2025 Apr 25-30; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2025;85(8_Suppl_1):Abstract nr 7163.

Abstract Background: Ovarian cancer is the sixth leading cause of cancer deaths among women in the United States. South Asians in the USA, including Asian Indians and Pakistani Americans (AIPA), are a rapidly growing yet under-researched group. This study aims to analyze the clinical features, survival rates, treatment, and outcomes of ovarian cancer among AIPA women in the United States. Methods: Adult women diagnosed with ovarian cancer between 2000 and 2023 within the Surveillance, Epidemiology, and End Results (SEER) registry were identified utilizing ICD codes. The analysis focused on comparing clinical characteristics and outcomes between AIPA and Non-Hispanic White (NHW)women and excluded all women of other races/ethnicities or unknown race/ethnicity. Baseline characteristics, including age at diagnosis, disease stage, and treatment, were compared between AIPA and NHW women utilizing a chi-squared test for categorical variables and a t-test for continuous variables. The 5-year overall survival (OS) was estimated for each race/ethnicity by the Kaplan-Meier method, and the OS was further compared between AIPA and NHW in a cox-proportional hazard regression analysis adjusting for age at diagnosis, grade, histology, TNM stage, surgical debulking, completeness of debulking surgery, and receipt of chemotherapy. Similar comparisons of baseline characteristics and OS were also performed in the subset of women with high-grade serous ovarian cancer (HGSOC). Result: A total of 86, 485 women met the inclusion criteria, of which 1, 179 were AIPA and 85, 306 were NHW. AIPA had a significantly younger median age at diagnosis compared to NHW women in the overall population (57 vs. 65 years, p&lt;0.001) and among 448 AIPA and 29, 677 NHW women with HGSOC (58 vs. 65 years, p&lt;0.001). Approximately two-thirds of women in both groups presented with Stage III or IV ovarian cancer at diagnosis and had a serous subtype of ovarian cancer. Similarly, after the exclusion of unknown grade, high-grade tumors accounted for more than two-thirds (75 vs. 72%) of the ovarian cancer cases in both groups. AIPA were more likely to undergo debulking surgery (85 vs. 80%, p&lt;0.001) and receive chemotherapy (77 vs. 72%, p&lt;0.001) compared to NHW women. The unadjusted 5-year OS for AIPA and NHW women were 56% vs. 43% in the overall population, and 53% vs. 41% among women with HGSOC, respectively. In multivariate analysis of the entire study population, AIPA women had a significantly better OS than NHW women (HR: 0.86, 95%CI: 0.79 - 0.94, p&lt;0.001). Among women with HGSOC, a similar trend of better OS was noted in multivariate analysis among AIPA women compared to NHW (HR: 0.88, 95%CI: 0.77 - 1.01, p=0.07), although this did not reach statistical significance. Conclusion: The younger age at diagnosis, along with a generally better prognosis, among AIPA women compared to NHW women, suggests a possible enrichment of DNA-repair gene alterations among AIPA women. Citation Format: Aditi Karki, Sumeet Kumar Yadav, Muhammad Rafiqul Islam, Raja Pramanik, Ramila Shilpakar Dangol, Zeba Aziz, Sandhya Pruthi, Maryam Shahi, Jamie N. Bakkum-Gamez, Scott H. Kaufmann, Fergus J. Couch, Siddhartha Yadav. Clinical characteristics and survival outcomes of ovarian cancer among South Asian women in United States [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2025; Part 1 (Regular Abstracts); 2025 Apr 25-30; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2025;85(8_Suppl_1):Abstract nr 7118.

Abstract Multiple myeloma (MM) is the second most common hematologic malignancy among US adults, characterized by high rates of relapse and refractory disease. Anti-Myeloma T cell immunotherapies, such as chimeric antigen receptors (CAR-Ts) and bispecific T cell engagers (BiTEs), have been able to induce deep responses in the clinic and extending survival for many. However, even these responses are not durable and majority of patients still relapse. MM cell signaling in response to cytokines released by these T cells, such as Tumor Necrosis Factor (TNF) Alpha, and Interferon gamma (IFNγ), may offer additional insight into mechanisms of relapse and resistance as well as avenues of therapeutic manipulation. To evaluate the effects of TNF and IFNγ on MM cell death and proliferation, we obtained human MM cell lines (MMCLs) and stably transduced them with a GFP-NLS reporter. We then monitored these cell lines in the presence of TNF, IFNγ, or TNF+IFNγ and tracked their cell death and growth kinetics over time using DiYO-3 incorporation and GFP count, respectively, via IncuCyteS3 live cell imaging. We next utilized Teclistamab, a B cell maturation antigen (BCMA)-directed BiTE, to co-culture MMCLs with healthy donor derived T cells at various effector to target (E:T) ratios and monitored for T cell mediated death again via IncuCyteS3 live cell imaging. While all MMCLs were able to be killed at high E:T ratios (1:1), only cytokine-sensitive lines remained susceptible to T cell killing at lower E:T ratios (1:10). The addition of TNF and/or IFNγ blocking antibodies confirmed that the increased sensitivity of these lines to T cell killing was indeed mediated by the two cytokines. In summary, were able to show an in vitro model of differential MM cell response to Teclistamab mediated T cell killing, and that this difference in response was predicated on the MM cells’ baseline sensitivity to cytokine mediated cell death via TNF and IFNγ. Thus, further dissecting mechanisms underlying resistance or sensitivity of MM cells to cytokine induced death could suggest therapeutic targets with the potential to enhance the efficacy of anti-MM T cell immunotherapies. Citation Format: Allison Carr, Adrian Ting. Role of cytokine-induced cell death on efficacy of teclistamab-mediated T cell killing of multiple myeloma cells. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2025; Part 1 (Regular Abstracts); 2025 Apr 25-30; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2025;85(8_Suppl_1):Abstract nr 1380.

Abstract Cholangiocarcinoma (CCA), an aggressive cancer of the bile ducts, is classified into intrahepatic (iCCA), perihilar (pCCA), and distal (dCCA) anatomic subtypes. Each subtype has a distinct epidemiology and pathogenesis. The tumor immune microenvironment (TIME) of each subtype is poorly understood. CCAs are poorly immunogenic tumors and systemic therapy has had subpar efficacy in CCA subtypes. Thus, we hypothesized that each anatomic subtype has a distinct TIME. To address this hypothesis, we completed single cell sequencing of tumor, liver, and bile duct from patients with either iCCA or pCCA/dCCA. 182,054 cells from paired liver (n=16), tumor (n=16) (9 iCCA, 7 pCCA/dCCA), and normal bile duct (n=9) samples were obtained from treatment-naïve patients undergoing resection from June 2020 to August 2023. The tissues were homogenized and flow sorted for immune (CD45+) populations immediately following resection. The cells then underwent single cell RNA sequencing (scRNA-seq) and cellular indexing of transcriptomes and epitopes by sequencing (CITE-seq) with antibodies for 157 proteins. Multiple immunocompetent, syngeneic/orthotopic murine models of iCCA with distinct genetic drivers were used to assess immunotherapeutics (PMID: 38458319). Immune cells of interest were isolated by flow sorting and functionally validated via suppression assays and multiparameter flow cytometry. Additionally, a novel pCCA murine model was established by injection of an Pik3caH1047R/p27Kip1-derived extrahepatic biliary cancer cell line into the porta/hilar tissue plane. Compared to non-involved liver, the bile duct immune microenvironment composition closely resembled that of the tumor. Multimodal analysis demonstrated both human and murine iCCA tumors have a significant upregulation of regulatory T cells (Treg) expressing T cell immunoreceptor with Ig and ITIM domain (TIGIT) compared to controls. Suppression assay with intratumoral TIGIT+ Treg from mouse compared with TIGIT- Treg indicate TIGIT+ Treg are more potent in inhibiting proliferation of CD8+ T cells. Moreover, TIGIT blockade using a monoclonal antibody resulted in a significant reduction in tumor burden in multiple iCCA murine models, including SB1, a model resistant to anti-PD-(L)1 monotherapy. Meanwhile, human pCCA tumors had a significant increase in IgA+ plasma cells compared to iCCA tumors. An innovative genetically and anatomically relevant pCCA murine model was developed to interrogate this unique plasma cell population. In summary, these data suggest that iCCA and pCCA have distinct immune microenvironments which likely impacts the differences in response to ICB between the subtypes observed in phase III clinical trials. Additionally, the uninvolved, tumor-adjacent bile duct immune microenvironment resembles that of the tumor, suggesting a pre-malignant niche that facilitates tumor development. Citation Format: Hannah E. Stumpf, Jingchun Yang, Haidong Dong, Rory L. Smoot, Sumera I. Ilyas. Multimodal single cell analysis of cholangiocarcinoma subtypes reveals distinct immune microenvironments [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2025; Part 1 (Regular Abstracts); 2025 Apr 25-30; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2025;85(8_Suppl_1):Abstract nr 6476.

Abstract Introduction: With over 80, 000 new cases of non-Hodgkin's lymphoma (NHL) diagnosed annually, modifiable risk factors remain unclear. Circadian disruption, linked to cancers like breast and prostate, affects immune cells (e.g., natural killer cells and T-helper cells) by altering their trafficking and proliferation. Some studies (PMID: 30566672, 27611440) suggest long sleep may increase overall NHL risk, including a Mendelian randomization (MR) study (PMID: 32895918). However, no research has examined the causal relationship between sleep traits, including long sleep, and NHL risk, by subtypes. We hypothesize that sleep traits are causally associated with NHL subtypes in European populations, testing this using MR with data from the International Lymphoma Epidemiology Consortium (InterLymph). Methods: We conducted two-sample MR using genome-wide association studies (GWAS) summary data for sleep traits and NHL subtypes. Only independent, genome-wide significant (p &lt; 5×10-8) Single Nucleotide Polymorphisms (SNPs) were selected as valid instruments, sourced from the UK Biobank. Sleep traits included chronotype (153 SNPs), insomnia (48 SNPs), sleep duration (78 SNPs), excessive daytime sleepiness (37 SNPs), short sleep (27 SNPs), and long sleep (8 SNPs). NHL subtype data were from InterLymph: follicular lymphoma (6, 508 cases / 64, 183 controls), mantle cell lymphoma (1, 169 cases / 61, 603 controls), Waldenstrom macroglobulinemia/lymphoplasmacytic lymphoma (WM/LPL: 1, 697 cases / 59, 333 controls), and chronic lymphocytic leukemia (8, 522 cases / 67, 653 controls). The primary analysis used inverse-variance weighted (IVW) random-effects, with MR-Egger for pleiotropy adjustment. Results: Using the IVW method, we did not identify any statistically significant causal association between sleep traits and the risk of NHL subtypes, but did yield several intriguing trends. Long sleep (sleep duration &gt;= 9 h per night) showed a marginally increased NHL risk [Odds ratio (OR) range: 1.51 - 247.9] across each subtype. Short sleep (sleep duration &lt; 7 h per night) showed a similar trend [OR range: 1.25 - 1.81], except for WM/LPL, where we noticed a negative trend. The confidence limit for long sleep was imprecise due to the small number of variants. We did not notice any significant directional horizontal pleiotropy or weak instrument bias. Conclusions: We found no conclusive evidence of a relationship between sleep traits and four NHL subtypes. However, we see suggestive trends of long and short sleep associated with higher risk of some NHL subtypes. These findings align with the previous studies, which showed long sleep was associated with higher risk of NHL overall. Future directions include expanding our analysis to additional NHL subtypes, generating polygenic risk scores, and conducting stratified analyses. Citation Format: Pankhil Shah, Brittany Crawford, Anwar Merchant, Brenda Birmann, Angelica Macauda, Michelle A. Hildebrandt, Aaron Norman, Neil E. Caporaso, Meredith Yeager, Michael Dean, Immaculata De Vivo, Lynn Goldin, Nicola J. Camp, Rosalie Griffin, Delphine Casabonne, Federico Canzian, Pelin Unal, Elad Ziv, Catherine R. Marinac, Alexandra Nieters, Stephen J. Chanock, Mitchell J. Machiela, Michael Conry, Charlie Zhong, Hanla A. Park, Simon Cheah, Jonathan N. Hofmann, Elizabeth E. Brown, Celine Vachon, Susan Slager, Sonja Berndt, Sophia S. Wang, Vijai Joseph, James McKay, Henrik Hjalgrim, Lara Sucheston-Campbell, Karl Smith-Byrne, Alyssa Clay-Gilmour. Association between sleep traits and risk of non-Hodgkin's lymphoma subtypes: a mendelian randomization study in the International Lymphoma Epidemiology (InterLymph) Consortium [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2025; Part 1 (Regular Abstracts); 2025 Apr 25-30; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2025;85(8_Suppl_1):Abstract nr 7415.