Abstract A041: Deciphering the bidirectional influences of sympathetic neurons and cancer associated fibroblasts and the resulting contributions to PDAC progression

Abstract The pancreatic ductal adenocarcinoma (PDAC) tumor microenvironment (TME) is innervated by a variety of peripheral nerves that are emerging as facilitators of tumor initiation, progression and metastasis. However, the influences of sympathetic nerves on the TME and how these bi-directional interactions can exacerbate PDAC progression remains unclear. Sympathetic nerves innervate both human and murine PDAC tumors and are frequently surrounded by abundant and heterogeneous cancer-associated fibroblasts (CAFs), which are known to play various crucial roles in PDAC progression. In our studies, we aim to elucidate the bidirectional CAF and sympathetic-neuron crosstalk that may promote tumor growth using a variety of in vitro coculture systems to model sympathetic-CAF interactions, as well as in vivo modeling of nerves in murine PDAC tumors. Our nerve-CAF cocultures reveal that CAFs closely and frequently interact with sympathetic nerves, and also enhance sympathetic nerve outgrowth. We further sequenced these cocultured conditions to evaluate intrinsic transcriptional changes that may be contributing to the enhanced nerve outgrowth. We identified several genes that may contribute to upregulated CAF adhesion, ECM deposition and neuroactive ligand-receptor interactions, which may also be supportive of the axon outgrowth and tumor cell growth. We are also currently characterizing human and murine PDAC samples that contain and lack sympathetic innervation to evaluate spatial phenotypic shifts within the TME. Collectively, our results suggest that this crosstalk between sympathetic neurons and CAFs may both enhance tumor innervation and tumor-promoting phenotypes in the TME, such as axonogenesis and fibrosis in PDAC. Citation Format: Ariana Sattler, Parham Diba, Tetiana Korzun, Marigold Kuykendall, Kevin MacPherson-Hawthorne, Mara Sherman, Teresa Zimmers, Sebnem E Eksi. Deciphering the bidirectional influences of sympathetic neurons and cancer associated fibroblasts and the resulting contributions to PDAC progression [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Advances in Pancreatic Cancer Research; 2024 Sep 15-18; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2024;84(17 Suppl_2):Abstract nr A041.