Roberts, Lewis R.

Abstract Introduction: Liver cancer remains a leading cause of cancer mortality globally with limited treatment options for patients (pts) with unresectable hepatocellular carcinoma [HCC] and intrahepatic cholangiocarcinoma [iCCA][1,2,3,4]. We hypothesize that combining the intratumoral dendritic cell (DC) vaccination after external beam radiotherapy (EBRT) without (phase I) and with (phase II) systemic atezolizumab and bevacizumab (atezo/bev for HCC) would enhance tumor-specific immunity and improve clinical outcomes, and present preliminary results from our phase I/II trial (NCT03942328). Methods: Peripheral blood mononuclear cells (PBMCs) were collected at baseline (PRE), after radiation (EBRT), and after completion of DC without or with atezo/bev (POST). Single-cell RNA sequencing with TCR sequencing were analyzed using CellRanger v7.0.1, Immunopipe, Seurat v5.3.0, & Gene-set enrichment analysis (GSEA). Long EFS (EFS-L) is defined as >=12 months (mo) for phase I and >=18mo for phase II, and short EFS (EFS-S) below that. Results: Seventeen patients have been analyzed to date (Phase I: n=8 [4 HCC, 4 iCCA]; Phase II: n=9 HCC). 674,106 cells were sequenced (146,843 PRE; 168,838 EBRT; 114,437 POST). GSEA for EFS-L vs EFS-S were comparable at PRE, EBRT and POST between phase I and phase II. EFS-S was associated with enrichment of interferon alpha (IFNα; B naïve, monocytes, pDC, cDC2, NK, Treg, CD8 Tcm and Tem at PRE and POST; B intermediate, CD4 Tem and NK at EBRT) and reactive oxygen species (ROS; PRE: pDC, CD8 Tcm, Tem. EBRT: CD4 Tem. POST: CD8 T naïve Tem, CD4 Tcm & Tem, cDC2) pathways. In contrast, EFS-L was associated with enrichment of WNT-β-catenin (WNT; CD14 mono at EBRT & POST, B intermediate at EBRT), TGFb (PRE: NK; EBRT: B intermed, CD4 Tem; POST: monocytes, CD4 naïve & Tem, pDC, cDC2), and angiogenesis (EBRT: NK; POST: monocytes, cDC2) pathways. Interestingly, enrichment of protein secretion pathway in NK cells was associated with EFS-L, but among other cells were associated with EFS-S (PRE: CD16 mono, Treg; POST: CD16 mono, CD4 & D8 Tem). Compared to phase I, addition of atezo/bev in phase II pts was associated with a significant increase in Gini coefficient (p<0.0001), suggesting expansion of certain TCR clones, along with a trend for increased Gini coefficient from Pre to Post in both phase I and II. Conclusions: Preliminary analysis of this study combining EBRT with intratumoral DC vaccination +/- PD-L1/VEGF blockade identified distinct treatment-related changes in systemic cellular immune profiles. Enhanced TCR clonal diversity in phase II suggests added immunologic benefit from PD-L1/VEGF blockade. As accrual continues, integrated analyses will identify systemic immune correlates of clinical benefit and resistance to this multimodal immunotherapy approach. Citation Format: Melody Wu, Panwen Wang, Chen Wu, Ying Li, Christopher L. Hallemeier, Thomas D. Atwell, Nguyen H. Tran, Andre de Menezes Silva Corraes, Kevin Regan, Zuoyi Shao, Rayaan Kamal, Haidong Dong, Lewis R. Roberts, Sean Park, Yi Lin, Lionel Aurelien Kankeu Fonkoua. Radiation-dendritic cell combination therapy drives systemic cellular immune shifts in liver 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 3741.

Abstract Background: Hepatocellular carcinoma (HCC) remains a leading cause of cancer-related mortality worldwide. Prognostic models for HCC primarily rely on tumor burden and liver function, with limited consideration of inherited genetic contributions to survival variability. Identifying germline variants associated with survival could refine prognosis and reveal biological mechanisms underlying disease progression. Methods: We conducted a genome-wide association study (GWAS) of overall survival among 864 patients with HCC from the M.D. Anderson Cancer Center cohort. Genotyping, quality control, and imputation procedures followed previously described protocols (PMID: 38381705). Associations between genetic variants and overall survival were assessed using Cox proportional hazards models adjusted for age, sex, and the first five principal components. Genome-wide significance was defined as P < 5×10-8. Functional annotation and pathway enrichment analyses (MAGMA) were employed to investigate the biological relevance of the identified loci. Results: After quality control, 8,525,017 single-nucleotide polymorphisms (SNPs) were analyzed. We identified seven new loci associated with HCC survival at the genome-wide significance level. Five out of seven loci are associated with anthropometric traits and hematological measurement traits, reflecting metabolism, hematopoiesis, immune function, and inflammation. A variant in the 3′ untranslated region (UTR3) of STX7 showed a genome-wide significant association with overall survival (HR = 3.23; P = 2.56 ×10-8). Carriers of the risk allele had significantly shorter survival times compared with noncarriers. Pathway analysis revealed enrichment in biologically relevant processes, including liver growth and regeneration (growth hormone and Interleukin-6 (IL-6) signaling pathway), implicating hepatocyte proliferation and IL-6/STAT3-mediated inflammatory signaling. Immune-related pathways, such as regulation of T cell activation and myeloid leukocyte migration, highlight the role of germline variation in immune surveillance. Moreover, pathways governing vascular remodeling and metabolic stress response (e.g., JAK activation, mitochondrial dynamics) suggest that inherited determinants of microenvironmental structure and hepatocyte resilience influence patient outcomes. Conclusion: This germline GWAS of HCC survival identifies seven new genome-wide significant loci and implicates pathways involved in liver regeneration, inflammation, and tissue remodeling. These findings support a role for inherited genetic variation in shaping HCC prognosis and underscore the potential of integrating germline genetics into prognostic modelling and therapeutic target discovery. Citation Format: Younghun Han, Jinyoung Byun, Lewis R. Roberts, Katherine A. McGlynn, Manal M. Hassan, Christopher I. Amos. Identification of survival-associated germline variants in hepatocellular carcinoma [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 3606.

Background: Blood-based biomarker panels, including GALAD, have been proposed as an alternative to abdominal ultrasound for hepatocellular carcinoma (HCC) surveillance. Studies suggest longitudinal evaluation of biomarkers can improve test performance; however, no large studies have validated these findings. Methods: We leveraged the HCC Early Detection Strategy (HEDS) study (n=1019 patients with cirrhosis; 99 incident HCC) and Texas HCC Consortium (THCCC) (n=2345 patients with cirrhosis; 126 incident HCC) to compare the performance of fixed-threshold GALAD (cutoff of −1.36), and 4 longitudinal algorithms: longitudinal GALAD, PALAD, mFB-ALAD, and mPEB-ALAD. The HEDS cohort was used to derive longitudinal algorithms, and external validation was performed in THCCC. Patient-level sensitivity and test-level false-positive rate (FPR) were examined overall and across subgroups by age, sex, and cirrhosis etiology. Results: In THCCC, fixed-threshold GALAD had higher sensitivity in the 6 months before HCC diagnosis (71.4%, 95% CI: 62.9%–81.7%) than longitudinal GALAD (55.1%, 95% CI: 49.3–66.4), PALAD (55.1%, 95% CI: 50.0%–70.5%), mPEB-ALAD (53.1%, 95% CI: 43.6%–62.0%), and mFB-ALAD (42.9%, 95% CI: 32.3–48.5). However, fixed-threshold GALAD had a higher FPR (25.4%, 95% CI: 23.7%–26.9%) compared with longitudinal GALAD (15.0%, 95% CI: 12.8%–15.8%), PALAD (13.0%, 95% CI: 10.2%–14.6%), and mFB-ALAD (11.2%, 95% CI: 9.6%–12.1%) but comparable to mPEB-ALAD (22.9%, 95% CI: 21.2%–23.8%). In subgroup analyses, fixed-threshold GALAD had the highest FPR in males (35.6%) and those aged ≥65 (43.5%); longitudinal algorithms had significantly lower FPRs in subgroups but with lower sensitivity for HCC. Conclusions: Improvements in FPRs with longitudinal GALAD algorithms, as compared with fixed-threshold GALAD, are offset by significantly decreased sensitivity for HCC detection.

Background and Aims: Cholangiocarcinoma (CCA) is a rare but aggressive malignancy with poorly understood genetic susceptibility. To date, genome-wide association studies (GWAS) investigating germline variants associated with CCA risk remain limited. We aimed to identify genetic risk loci for CCA and its clinical subtypes through comprehensive GWAS and post-GWAS analyses. Approach and Results: We conducted a GWAS of 2366 CCA cases and 11,750 controls of European ancestry. Genome-wide significant loci ( p <5×10 −8 ) were identified and further examined through fine-mapping, functional annotation, and HLA imputation. Subgroup analyses were conducted by CCA subtypes and primary sclerosing cholangitis (PSC) status. Cross-trait linkage disequilibrium score regression and Mendelian randomization were employed to investigate the shared genetic architecture and potential causal relationships with a diverse range of traits. We identified 1 new genome-wide significant variant, rs535777 (OR=1.44), near HLA-DRB1/DQA1 associated with CCA, and 2 variants associated with extrahepatic CCA: rs116224263 (OR=0.17) in LINC02506 at 4p15.1 and rs6914950 (OR=1.63) near HLA-DRB1/DQB1 . Stratified analyses revealed rs2395184 (OR=3.51) near HLA-DRA/DRB5 associated with PSC-related CCA, and rs142674434 (OR=2.98) in THSD7A at 7p21.3 associated with non-PSC-related CCA. HLA imputation uncovered new amino acid residues associated with disease risk. Cross-trait analyses identified shared genetic signals between CCA and anthropometric, lipidemic, lifestyle, and medical traits. Mendelian randomization supported putative causal associations for 12 traits with CCA or its subtypes. Conclusions: Our large-scale GWAS highlights new genetic variants and HLA-linked mechanisms underlying CCA susceptibility. Integrating multi-step post-GWAS approaches enhances understanding of CCA pathogenesis and may facilitate the development of risk biomarkers for early detection and precision prevention strategies.