Abstract 2348: Unveiling dichotomies between liver cancer and adjacent normal tissues in Wilson’s disease model

Abstract Objective: The Long-Evans Cinnamon (LEC) rat is a model for Wilson’s disease (WD) and is associated with chronic inflammation and hepatocellular carcinoma. This study performed a gene expression microarray using total RNA extracted from LEC liver tissue at 84 weeks late chronic hepatitis, tumor-adjacent normal (84 weeks N), and 84 weeks tumor (84 weeks T). Understanding the difference between a tumor and adjacent normal within the same animal can be very intriguing as both are in the same environment, and one becomes and sustains a tumor status, but the other still maintains its normalcy. Experiment: Total RNA was extracted from liver tissue of three LEC rats at 84 weeks N and 84 weeks T and hybridized to the Affymetrix GeneChip Rat Genome 230 2.0 Array (Affymetrix Inc, Santa Clara). GeneGO Pathways software was used to analyze the differentially expressed genes using a cutoff of P-value ≤0.05 and FDR <0.25% and a fold change +/- 2. A volcano plot was generated to visualize significant gene change expression between 84 weeks N vs 84 weeks T. Agglomerative Hierarchical and K-means clustering were used to group similarly expressed genes into clusters and build a hierarchy of clusters. Each cluster obtained from K-means clustering analysis within the up or down-regulated groups were checked for pathway analysis to understand the interplay between biological pathways by QIAGEN Ingenuity® Pathway Analysis (QIAGEN IPA). In addition − log(p) > 1.3, a z-score cut-off͕ ≥ 2 for activation and a z-score cutoff ≤ -2 for inhibition was used to call a pathway activation, and inhibition is significant. Result: The seven most significant pathways that were activated are the S100 Family Signaling Pathway, Extracellular Matrix Organization, Response to Elevated platelet cytosolic Ca2+, HMGB1 Signaling, Sertoli Cell-Sertoli Cell Junction Signaling, Cachexia Sunaina Pathway, and Nicotine Degradation II. Except for Nicotine Degradation II pathway, all other pathways are shown activated in non-alcoholic fatty liver disease (NAFLD) and hepatocellular carcinoma (HCC) patients previously but shown in the WD model for the first itme. The Nicotine Degradation II pathway is shown to be activated in the NAFLD patient before. Conclusion: To our knowledge, this is the first report where gene expression analysis was done between tumor-adjacent normal and tumor within the same animal in the WD model. Our results identified multiple pathways in the model that could lead us to new diagnostics and therapeutic targets when validated. Citation Format: Ritam Adhikari, Chiranjeev Dash, Rabindra Roy. Unveiling dichotomies between liver cancer and adjacent normal tissues in Wilson’s disease model [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 2348.