Abstract 1592: Single-cell transcriptomics reveals unique stromal and metabolic heterogeneity in liver metastatic pancreatic cancer

Abstract Pancreatic ductal adenocarcinoma (PDA) is the 3rd leading cause of cancer related death in the US. This mortality is strongly linked to the complex PDA tumor microenvironment that drives resistance to chemotherapy and immune suppression. Most patients succumb to metastatic disease, with liver being the most frequently colonized organ. Despite this, most pre-clinical studies have focused on primary PDA models to study the disease. Accordingly, the extent that the liver metastatic niche promotes immune evasion and resistance to treatment remains unclear. To directly compare primary vs. metastatic tumors in PDA tumors, we have optimized a syngeneic experimental model to contrast primary vs. metastatic lesions. To define the similarities and differences between cell types present in these tumors, we employed a single-cell transcriptomics approach. Our analysis has identified shared populations of malignant epithelial, stromal, and immune cells between lesions, allowing for a direct comparison of programming. Here, we have observed that the dominant populations of PDA cells in pancreas vs. liver tumors engage in distinct metabolic programs that suggest different actionable vulnerabilities. Beyond these, we also observed fibroblasts and myeloid sub-populations that are exclusive to liver tumors. These data further support our hypothesis that alternative mechanisms of metabolic, immune, and stromal interactions take place in the metastatic tumor microenvironment. To define these crosstalk networks, we employed the interactome tool CellChat, which has uncovered unique signaling interactions between the CAF and cancer cell populations in pancreatic or liver tumors. Overall, these data have the potential to lead to new avenues to directly target cancer cells or engage an effective immune response that can be designed to treat metastatic pancreatic cancer- an urgent clinical need. Citation Format: Rima Singh, Christopher Halbrook. Single-cell transcriptomics reveals unique stromal and metabolic heterogeneity in liver metastatic pancreatic cancer abstract. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts) ; 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84 (6Suppl): Abstract nr 1592.