Abstract 637: Cytokine CCL9 mediates oncogenic Kras-induced pancreatic acinar-to-ductal metaplasia through ROS

Abstract Pancreatic ductal adenocarcinoma (PDAC) can be originated from acinar-to-ductal metaplasia (ADM). Pancreatic acini harboring oncogenic Kras mutations are transdifferentiated to a duct-like phenotype that further progresses to become pancreatic intraepithelial neoplasia (PanIN) lesions, giving rise to PDAC. Although ADM formation is frequently observed in KrasG12D transgenic mouse models of PDAC, the exact mechanisms of how oncogenic KrasG12D regulates this process remain an enigma. Herein we reveal a new downstream target of oncogenic Kras, cytokine CCL9 during ADM formation. Exogenously treating primary pancreatic acini with recombinant CCL9 in a 3D organoid culture system drives ADM formation. Furthermore, knockdown of CCL9 in KrasG12D-expressed acini reduced KrasG12D-induced ADM. Higher levels of reactive oxygen species were detected in the KrasG12D-expressed pancreatic acini, and knockdown of CCL9 in these acini dramatically decreased ROS levels. Depletion of ROS in 3D organoid culture of CCL9-expressed acini reduced CCL9-induced ADM formation. In transgenic mice of p48cre:KrasG12D, depletion of CCL9 through its specific neutralizing antibody attenuated ADM formation as well as PanIN structures. Hence, our results provided insight into how oncogenic Kras regulates pancreatic ADM through a new downstream target molecule, CCL9. Citation Format: Geou-Yarh Liou, Justin K. Messex, Kiyah L. Adams. Cytokine CCL9 mediates oncogenic Kras-induced pancreatic acinar-to-ductal metaplasia through ROS [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 637.