Research on uPAR promoting proliferation, migration, and chemoresistance of pancreatic cancer by inhibiting autophagy via MAPK signaling

Background and purpose: Amplification of the urokinase plasminogen activator receptor (uPAR) gene is closely associated with poor prognosis in pancreatic cancer patients. uPAR regulates epithelial-mesenchymal transition (EMT) and chemoresistance in pancreatic cancer cells through the mitogen-activated protein kinases (MAPK) signaling pathway, though the specific mechanisms remain unclear. This study aimed to investigate the mechanism by which uPAR promotes proliferation, invasion, and chemoresistance of pancreatic cancer cells by inhibiting autophagy. Methods: Pancreatic cancer tissue samples were collected from patients who underwent surgical resection and biopsy at the Changsha Central Hospital, Affiliated to University of South China (Changsha Central Hospital), between December 2021 and Jun 2022. The study was approved by the Ethics Committee of Changsha Central Hospital (Approval No.: 2021-S0182, 2022-S0084). Patient-derived organoids (PDOs) from pancreatic cancer samples were cultured in vitro. Six pancreatic cancer cell lines (AsPC-1, PANC-1, CAPAN-1, CAPAN-2, MIA PaCa-2 and PaTu8988T) were used in this study. uPAR-deficient models were constructed using clustered regularly interspaced short palindromic repeats (CRISPR) Cas9 technology. Cell proliferation and invasion abilities were measured using confocal microscopy, Western blot, enzyme-linked immunosorbent assay (ELISA), and MTS assays. Changes in MAPK and autophagy signaling pathways and gemcitabine-induced cell death were analyzed. The synergistic effects of combined treatments were evaluated using gene silencing (siRNA) or autophagy inhibitors. Results: In AsPC-1 cells, uPAR knockout significantly reduced the proliferation and migration abilities of clone cells compared to wild-type cells, as shown by MTS assays and wound healing experiments, and decreased sensitivity to gemcitabine (P