Tehran University of Medical Sciences Iranian Journal of Allergy, Asthma and Immunology 1735-1502 23 6 2024 12 29 727 737 Yong Tao Department of General Surgery, XuanCheng People's Hospital, Affiliated Xuancheng Hospital of Wannan Medical College, AnHui, China Chengniu Chu Department of General Surgery, XuanCheng People's Hospital, Affiliated Xuancheng Hospital of Wannan Medical College, AnHui, China Dongjun Sun Department of Information, XuanCheng People's Hospital, Affiliated Xuancheng Hospital of Wannan Medical College, AnHui, China Junfeng Xiang Department of General Surgery, XuanCheng People's Hospital, Affiliated Xuancheng Hospital of Wannan Medical College, AnHui, China Bo Wu Department of General Surgery, XuanCheng People's Hospital, Affiliated Xuancheng Hospital of Wannan Medical College, AnHui, China Cong Li Department of General Surgery, XuanCheng People's Hospital, Affiliated Xuancheng Hospital of Wannan Medical College, AnHui, China Wei Cui Department of General Surgery, XuanCheng People's Hospital, Affiliated Xuancheng Hospital of Wannan Medical College, AnHui, China 2024 02 05 2024 07 17 Pancreatic ductal adenocarcinoma (PDAC) is a common digestive system tumor with high mortality rates and a poor prognosis. Reports suggest that microRNA (miR)-486-3p in PDAC can be used as a diagnostic biomarker. This research aimed to elucidate the mechanisms by which miR-486-3p regulates PDAC progression. miR-486-3p and chymotrypsin C (CTRC) expression in PDAC were measured using quantitative real-time polymerase chain reaction. Changes in the biological properties of PDAC cells were assessed by Transwell assay, scratch-wound assay, cell counting kit (CCK)-8 assay, and plate cloning assay. The protein expression of immunosuppressive factors (vascular endothelial growth factor, interleukin-6, and transforming growth factor-β) in PDAC cells was detected by western blot. Additionally, a subcutaneous graft tumor model was constructed to explore the influence of silencing miR-486-3p on PDAC in vivo. PDAC showed a pronounced increase in miR-486-3p expression. Upregulation of miR-486-3p stimulated PDAC cell proliferation, migration, invasion, and immunosuppressive factor protein expression, whereas silencing miR-486-3p hindered PDAC malignant development. miR-486-3p targets and negatively regulates CTRC expression. Silencing CTRC partially rescued the restraining impact of silencing miR-486-3p on PDAC malignant progression. In vivo experiments also indicated that silencing miR-486-3p inhibited PDAC malignant progression and immunosuppressive factor expression in vivo. In summary, miR-486-3p promotes immunosuppressive factor protein expression by targeting and negatively regulating CTRC expression, which in turn promotes PDAC malignant progression. https://ijaai.tums.ac.ir/index.php/ijaai/article/view/4027 https://ijaai.tums.ac.ir/index.php/ijaai/article/download/4027/2137