Tumor–Stromal Interactions in a Co-Culture Model of Human Pancreatic Adenocarcinoma Cells and Fibroblasts and Their Connection with Tumor Spread
Elena Prieto‐García, C. Vanesa Díaz-García, Alba Agudo-López, Virginia Pardo, Inés García‐Consuegra, Sara Marcos Asensio, Marina Alonso, Carlos Pérez‐Plasencia, Carlos F. Gómez, Jorge Adeva, Luis Paz‐Ares, José A. López-Martín, M. Teresa Agulló-Ortuño
Abstract
One key feature of pancreatic ductal adenocarcinoma (PDAC) is a dense desmoplastic reaction that has been recognized as playing important roles in metastasis and therapeutic resistance. We aim to study tumor-stromal interactions in an in vitro coculture model between human PDAC cells (Capan-1 or PL-45) and fibroblasts (LC5). Confocal immunofluorescence, Enzyme-Linked Immunosorbent Assay (ELISA), and Western blotting were used to evaluate the expressions of activation markers; cytokines arrays were performed to identify secretome profiles associated with migratory and invasive properties of tumor cells; extracellular vesicle production was examined by ELISA and transmission electron microscopy. Coculture conditions increased FGF-7 secretion and α-SMA expression, characterized by fibroblast activation and decreased epithelial marker E-cadherin in tumor cells. Interestingly, tumor cells and fibroblasts migrate together, with tumor cells in forming a center surrounded by fibroblasts, maximizing the contact between cells. We show a different mechanism for tumor spread through a cooperative migration between tumor cells and activated fibroblasts. Furthermore, IL-6 levels change significantly in coculture conditions, and this could affect the invasive and migratory capacities of cells. Targeting the interaction between tumor cells and the tumor microenvironment might represent a novel therapeutic approach to advanced PDAC.