Abstract
MicroRNAs (miRNAs) play crucial roles in the pancreatic carcinogenesis and progression. In the present study, we found that miR-9-5p was significantly downregulated in pancreatic cancer tissues and cell lines. The expression levels of miR-9-5p were negatively correlated with tumor stage and vessel invasion. Log-rank tests demonstrated that low expression of miR-9-5p was strongly correlated with poor overall survival in pancreatic cancer patients. Moreover, overexpression of miR-9-5p remarkably inhibited pancreatic cancer cell proliferation by enhancing cell apoptosis and significantly suppressed the invasion of pancreatic cancer cells, whereas low expression of miR-9-5p exhibited the opposite effect. Bioinformatics analysis revealed that GOT1 was a potential target of miR-9-5p, and miR-9-5p inhibited the expression level of GOT1 mRNA by direct binding to its 3'-untranslated region (3'UTR). Expression of miR-9-5p was negatively correlated with GOT1 in pancreatic cancer tissues. Moreover, modulation of miR-9-5p expression could affect the glutamine metabolism and redox homeostasis in pancreatic cancer cells. Furthermore, downregulation of GOT1 counteracted the effects of miR-9-5p repression, whereas its overexpression reversed tumor inhibitory effects of miR-9-5p. Collectively, this study suggested that miR-9-5p regulates GOT1 expression in pancreatic cancer, thereby stunting proliferation, invasion, glutamine metabolism and redox homeostasis, and that miR-9-5p may serve as a prognostic or therapeutic target for pancreatic cancer.