Citations

Abstract Background Isocitrate dehydrogenase (IDH)-mutant gliomas are infiltrative tumors with limited treatment options at recurrence. Early studies suggest IDH inhibition has therapeutic activity. We evaluated clinical outcomes associated with IDH-1 inhibitor ivosidenib in recurrent IDH-1-mutant gliomas and molecular predictors of response. Methods We retrospectively analyzed adults treated with ivosidenib from January 2021 to August 2025 with predominantly recurrent, pretreated CNS WHO grade 2-4 astrocytoma IDH-mutant or grade 2-3 oligodendroglioma, IDH-mutant and 1p/19q codeleted. Prior anticancer treatments, toxicities, enhancement status at ivosidenib initiation, and genomic alterations were collected. The primary endpoint was progression-free survival (PFS); secondary analyses evaluated associations between PFS, genomic complexity, and CDKN2A/B homozygous deletion. Results Ninety-two adults, median age 43, were included: 61 astrocytomas and 31 oligodendrogliomas, mostly grade 2. Before ivosidenib, 69 had surgery, 64 chemotherapy, and 64 radiation. Median time from diagnosis to ivosidenib was 4.8 years, with median of two prior progressions. Median treatment duration was 5.8 months. Median PFS was 15.2, 4.6, and 2.1 months for astrocytoma grades 2-4, 14.0 and 6.9 months for oligodendroglioma grades 2-3. Increasing genomic complexity was associated with shorter PFS in univariate analysis. Patients without CDKN2A/B homozygous deletion had median PFS of 19.2 months. Two patients with homozygous deletion had median PFS of 0.6 months. Conclusions In this retrospective analysis of predominantly recurrent IDH-1-mutant glioma, ivosidenib was associated with longer PFS in lower-grade, non-enhancing tumors that received little or no prior anticancer treatment and less complex genomic profiles. These findings support a context-dependent benefit of IDH inhibition in recurrent disease.

Abstract Pancreatic cancer disproportionately affects Black individuals in the United States, but they have limited representation in genetic studies of pancreatic ductal adenocarcinoma (PDAC). To address this gap, we performed admixture mapping and genome-wide association analysis (GWAS) in genetically inferred African ancestry individuals (1,030 cases and 889 controls). Admixture mapping identified three regions with a significantly higher proportion of African ancestry in cases compared to controls (5q33.3, 10p1, 22q12.3). GWAS identified a genome-wide significant association at 5p15.33 ( CLPTM1L , rs383009:T>C, T Allele Frequency=0.51, OR:1.45, P value=1.24×10 -8 ), a locus previously associated with PDAC. Known loci at 5p15.33, 7q32.3, 8q24.21 and 7q25.1 also replicated (P value <0.01). Multi-ancestral fine-mapping identified two potential causal SNPs (rs3830069 and rs2735940) at 5p15.33. Collectively these findings identified novel PDAC risk loci and expanded our understanding of this deadly cancer in underrepresented populations, emphasizing the multifactorial nature of PDAC risk including inherited genetic and non-genetic factors. Statement of Significance To understand how genetic variation contributes to PDAC risk in Black people in North American, we studied individuals of genetically-inferred African ancestry. We identified novel risk loci and differences in the contribution of known loci. This demonstrates that ancestry-informed genetic analyses improve our understanding of PDAC risk and enhances discovery.

Abstract Oncology Advanced Practice Providers (APPs), including Advanced Practice Registered Nurses, Physician Assistants, and Clinical Pharmacists (CPs), play a vital role in delivering high-quality, patient-centered cancer care across the United States. Despite their widespread presence in oncology practices, APPs remain underutilized in cancer clinical research, representing a missed opportunity to expand trial access and improve patient outcomes. Clinical trials are essential to advancing oncology care, yet participation remains critically low among adult patients. Given Oncology APPs’ and CPs’ central role in cancer care delivery, their meaningful engagement in oncology clinical trial research is imperative as the standard of oncology care. This position article, with contributions from 5 professional societies, presents solutions and resources to barriers limiting APPs’ and CPs’ involvement in cancer clinical research, including gaps in education, role expectations, limited protected time, restrictive policies, insufficient financial support, and underrecognition of contributions. Integrating APPs and CPs more fully into the clinical research enterprise is essential to improving trial access, patient outcomes, closing equity gaps, and accelerating innovation in oncology care.

Emergence of epidemic viruses in new hosts threatens both human and other animal populations, and often involves virus evolution to overcome barriers that normally prevent efficient infection and spread in that host. After transfer the separated viruses will evolve in parallel as they spread within the original and new hosts. Here we examine the details of a virus involved in such a host-jumping event, where we define the natural evolution of feline panleukopenia virus (FPV) over 60 y, clarify the origins of the new pandemic canine parvovirus (CPV) that arose in the 1970s, and compare the separate evolution of those viruses over 47 y in cats or dogs. Several live-attenuated FPV vaccine viruses originated from early-1960s isolates or were a recombinant of an early virus, and many sequences in databases proved to be vaccine-derived. The sequences of wild viruses showed that FPV-like strains evolved at less than one-third the rate observed for CPV in dogs, and the higher rate of CPV evolution has been consistent since 1979, when a genetic variant became widespread. The common ancestor of the CPV lineage was related to FPVs from Europe and contained several unique host-adaptive capsid changes associated with canine transferrin receptor type-1 binding. Although the FPV vaccine strains are around 60 y old, little selection for antigenic variation was observed. The distinct evolutionary patterns of these closely related viruses circulating for decades in different hosts emphasize the complex evolution associated with viral epidemic emergence and spread in endemic and new hosts.

Abstract We evaluated outcomes by management type for patients with stage IA nodular lymphocyte-predominant Hodgkin lymphoma (NLPHL) in the Global NLPHL One Working Group retrospective database of 2243 patients with stages I to IV disease diagnosed from 1992 to 2021 at 38 international institutions. A total of 779 patients had stage IA disease with median age of 35 years (range, 3-89) and median follow-up of 6.1 years. The 6-year progression-free survival (PFS) and overall survival were 86.3% and 97.7%, respectively. Outcomes were analyzed for the 2 groups: complete resection and unresected disease. Patients with a complete resection and observation alone (n = 99) had a 6-year PFS of 65.5% vs 90.5% for those who received radiotherapy (RT) (n = 53). Patients with unresected disease (n = 627; 80.5%) had a 6-year PFS of 62.0% for rituximab alone (n = 31), 89.6% for RT alone (n = 325), 76.8% for ABVD (doxorubicin, bleomycin, vinblastine, dacarbazine) alone (n = 40), and 94.3% for ABVD plus RT (n = 130). A total of 127 patients relapsed (16.3%), of which 25 (19.7%) had transformation. Our analysis suggests the following: (1) RT improves the PFS in patients with completely resected disease; (2) rituximab or ABVD alone does not appear to achieve a durable response; and (3) chemotherapy was not observed to add additional PFS benefit when used in combination with RT. Thus, for stage IA NLPHL, RT alone is likely sufficient for definitive treatment.

Abstract The sentinel lymph node (SLN) is often the first site of melanoma spread and a critical immune checkpoint that determines local tumor dissemination to systemic metastasis. Although lymph nodes are central to antitumor immunity, the mechanisms that render them permissive to metastasis remain poorly understood. This study used spatial imaging to characterize immune and stromal phenotypic alteration in tumor-negative SLNs (SLN-) and tumor-positive SLNs (SLN+) from patients with cutaneous melanoma, compared to non-melanoma-associated normal lymph nodes (NLN). We performed multiplex immunofluorescence (MxIF) analysis of formalin-fixed, paraffin-embedded lymph node tissues from patients with cutaneous melanoma and control subjects, including two subjects per group (NLN, SLN-, and SLN+). Furthermore, quantitative single-cell segmentation and classification using QuPath generated median fluorescence intensities for immune, stromal, and tumor markers across LN, SLN- and SLN+ regions of interest. In addition to the initial analysis, we employed spatial neighborhood analysis to characterize markers expression profiles surrounding target immune population. This approach quantified local microenvironment based on marker normalized intensity-based co-expression pattern and stromal remodeling signatures. We grouped these markers based on the functional panels representing T-cell activation and exhaustion, myeloid polarization, tumor interaction, stromal remodeling, and apoptosis pathways providing insights into how prometastatic niche evolve within SLN. Normalized data, via centered log ratio (CLR) transformation and Gaussian Mixture Model (GMM) gating was analyzed using principal component analysis, UMAP/tSNE embedding, and hierarchical clustering in in python. Progressive immune remodeling was observed from normal NLN to SLN+, including expansion of regulatory T cells, enrichment of exhausted T cells as well as myeloid-derived suppressor cells (MDSC), and transition toward an M2-like macrophage phenotype. The spatial data from SLN- samples showed an early sign of immune suppression, with reduced cytotoxic capacity. These results show that SLN gets features of peripheral immune tolerance for melanoma early, prior to pathological dissection of metastatic spread supporting the existence of a pre-metastatic niche that facilitates lymphatic colonization of tumor cells. This work provides insights into early immune escape and may inform strategies for immunotherapy and early intervention in melanoma. Citation Format: Shankar Suman, Wendy K. Nevala, Noah A. Stueven, Raymond M. Moore, Chathu L. Atherton, Jeffrey E. Johnson, Ray Guo, James W. Jakub, Svetomir N. Markovic. Spatial remodeling of immune and stromal microenvironments in sentinel lymph nodes during melanoma progression [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 6193.

Abstract Introduction: Placental cell-free DNA (cfDNA) activates maternal monocytes to a proinflammatory phenotype through cGAS-STING signaling during pregnancy, thereby stimulating T cells. We sought to engineer DNA nanocarriers that reproduce this mechanism in human monocytes using clinically translatable materials as a strategy for tumor-associated macrophage (TAM) reprogramming. Methods: A synthetic mimic of fetal cfDNA (scfDNA) was designed, commercially synthesized, and complexed with polyethylenimine (PEI) to form scfDNA-PEI nanoparticles (scfDNA-PEI-NPs) for cytosolic delivery. THP-1 Dual reporter monocytes expressing interferon regulatory factor (IRF)-inducible luciferase were treated with scfDNA-PEI-NPs or human cytotrophoblast derived cfDNA (CTB-DNA) to quantify cGAS-STING-IRF activation. Cytotoxicity was assessed by lactate dehydrogenase (LDH) release to define a non-toxic therapeutic window. Results: scfDNA-PEI-NPs triggered robust cGAS-STING-IRF activation in THP-1 monocytes, exceeding CTB-DNA responses. This response was abolished in cGAS-knockout cells and rescued by a cGAS-independent stimulator of the IRF pathway, confirming cGAS specificity of scfDNA-PEI-NPs. Dose-response analysis showed a &gt; 10-fold separation between cGAS-activating and cytotoxic concentrations, establishing a therapeutic window for myeloid-selective cGAS activation. Conclusions: These findings provide proof-of-concept that pregnancy-inspired DNA nanocarriers can reproduce fetal cfDNA-driven activation of a proinflammatory monocyte phenotype in vitro. This platform lays the groundwork for future work on macrophage-targeted cGAS activation and proinflammatory reprogramming for tumor immunotherapy development. Citation Format: Mathew R. Schnorenberg, Elizabeth Ann L. Enninga, Wendy K. Nevala, Noah A. Stueven, Svetomir N. Markovic, . Pregnancy-inspired DNA nanocarriers reproduce a cGAS-driven pro-inflammatory monocyte phenotype [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 4307.

Abstract Background: Pediatric and AYA sarcomas are rare, biologically heterogeneous tumors with limited noninvasive biomarkers to guide diagnosis, personalized treatment, and disease monitoring. Standard-of-care evaluation relies on invasive biopsies that carry procedural risks and imaging modalities with limited sensitivity for detecting minimal residual disease and distinguishing tumor types. Cell-free DNA (cfDNA) methylation profiling offers a minimally invasive alternative capable of capturing tumor-derived epigenomic alterations and has consistently shown strong clinical utility in adult malignancies. However, genome-wide cfDNA methylation patterns across diverse pediatric and AYA sarcoma subtypes remain poorly defined. Methods: Plasma was collected from 93 pediatric and AYA patients (pediatric &lt;18 years; AYA 15-39 years) representing 27 Ewing sarcoma, 17 rhabdomyosarcoma, 11 liposarcoma, 10 chordoma, 8 synovial sarcoma, 7 chondrosarcoma, 6 osteosarcoma, and 6 fibrosarcoma cases, plus 19 matched healthy donors. cfDNA was isolated from 1 mL plasma, quantified by Qubit, and assessed by Bioanalyzer. Libraries were prepared using the NEBNext EM-seq v2 workflow with PCR cycles scaled to cfDNA input amount. Genome-wide sequencing (15× target depth) was followed by alignment, deduplication, and methylation calling. MultiQC was used to assess depth, duplication rate, conversion efficiency, and CpG coverage. Global methylation summaries were computed, and methylKit was used to generate per-CpG and 1-kb tiling matrices and initiate differential methylation analyses. Results: Ewing sarcoma patients had significantly higher plasma cfDNA concentrations than age- and sex-matched healthy donors (24.4 vs 4.6 ng/mL, p &lt; 0.0001), whereas cfDNA levels for other sarcoma subtypes overlapped with the healthy cohort. Low or undetectable cfDNA concentrations by Qubit were far more common among non-Ewing sarcoma samples (23 of 66) than Ewing sarcoma (1 of 27). All samples achieved sufficient CpG coverage for genome-wide methylation modeling. Global methylation summaries revealed no significant differences in mean β-values across sarcoma subtypes or versus healthy donors. An independent analysis of the Ewing subset identified 299 significant differentially methylated regions (DMRs), supporting the detectability of disease-specific methylation changes. Conclusions: These results demonstrate the feasibility of high-quality cfDNA methylome profiling across a large and diverse pediatric and AYA sarcoma cohort, including in plasma samples with cfDNA concentrations below the limit of detection. While global methylation levels appear broadly similar across subtypes, proof-of-concept DMR analysis in Ewing sarcoma suggests that subtype-specific epigenomic signatures could enable future noninvasive diagnostic tools for pediatric and AYA sarcomas. Citation Format: Lilli J. Greiner, Roman O. Kowalchuk, Jeff Szymanski, Pradeep S. Chauhan, Adam Amundson, Peter J. Schoettler, Wendy Allen-Rhoades, Stephanie F. Polites, Peter S. Rose, Kelly Bailey, Linda McAllister-Lucas, Anita Mahajan, Nadia Laack, Aadel Chaudhuri. Defining genome-wide cfDNA methylation landscapes in pediatric and adolescent and young adult (AYA) bone and soft-tissue sarcomas [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 7885.

Abstract Our team has demonstrated that lymphatic exudate collected via surgical drains (“lymph”) is a proximal biofluid rich in ctDNA and prognostic of recurrence in HPV-independent Head and Neck Cancer (HPV- HNSCC). Other analytes such as proteins, metabolites, and cells are also abundant in lymph. To understand the liquid tumor microenvironment (TME) immediately after tumor resection, we characterized lymph at 24 hrs in HNSCC. We performed a multi-omic survey, demonstrating that lymph is distinct from plasma and represents a largely unexplored source of biomarkers relevant to immune modulation and metastasis.Metabolomics and proteomics were run on lymph supernatant and plasma. Proteomic screening was performed via Olink and normalized to internal standards for quantitative analysis. Metabolomic samples were assayed via LC-MS and normalized. 16s libraries were sequenced utilizing Illumina and analyzed in QIIME. 16s sequencing on 6 patients indicated an array of bacterial genera present in post-surgical lymph with consistency across patients. The distribution consisted primarily of microbes native to the oral cavity, suggesting post-surgical lymph may reflect the native microbiome prior to surgery. Pathogenic blooms were observed in a subset of patients. Ongoing analysis will correlate microbiome data with both cancer and surgical outcomes.Metabolite profiling was performed on post-surgical lymph and matched plasma from 4 patients, including 3 who recurred within 1 year of surgery. The metabolite profile in lymph of all 4 patients was more diverse than plasma with higher metabolite abundance per mL. 13% of identified metabolites were &gt;2-fold enriched in lymph. Lymph from recurred patients showed high levels of saturated and monounsaturated fatty acids, reported to be associated with metastasis. Post-surgical lymph has a unique and largely uncharted metabolome to mine for biomarkers associated with recurrence.Proteomes were compared between lymph and plasma from 44 HPV-HNSCC patients. This cohort consists of 25 recurred (REC) and 19 patients with no evidence of disease (NED) with &gt;1 year of follow up. Lymph and plasma displayed highly non-overlapping protein repertoires. The mean absolute volcano score was 25.2, indicating a strong global difference between lymph and plasma. Lymph was significantly enriched in 91 proteins (p range 4.1e-47 to 0.037), many associated with inflammation. REC lymph was also enriched in inflammatory markers compared to NED, including IL-1a, TNF, and TSLP (p = 0.002, 0.015, 0.003, respectively), which have been implicated in cancer metastasis, invasion, and angiogenesis. Lymph hits were largely non-overlapping with plasma, indicating the opportunity for novel biomarker discovery in this fluid.Analysis of the microbiome, metabolome, and proteome of post-surgical lymph reveals a rich and differentiated tumor-adjacent biofluid to study biomarkers relevant to metastasis and the TME. Citation Format: Zachary Costliow, Seka Lazare, Zhuosheng Gu, Adam Harmon, Maciej Pacula, Megan Rivera, Aadel A. Chaudhuri, Jose P. Zevallos, Jessalyn Marie Ubellacker, Wendy Winckler. Multi-omicsinpostoperative lymphatic exudate in HPV-negative head and neck 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 6137.