miR-181a negatively regulates Kras to inhibit the proliferation and migration of cholangiocarcinoma cell line QBC939

Objective: To investigate whether miR-181a can regulate the expression of Kras to affect the proliferation and migration of cholangiocarcinoma cell line QBC939. Methods: QBC939 cells were divided into D group (cells without treatment), Dz group (cells transfected with negative control), Dm group (cells transfected with miR-181a inhibitor), and Dy group Dy (cells transfected with miR-181a mimics). The morphology of cells was observed by Hoechst staining, and the expression of Kras mRNA and miR-181a was determined by RT-PCR. The expression of Kras protein was detected by Western blot, and the invasion ability of QBC939 cells was detected by transwell assay. Clone formation assay and MTT assay were used to detect cell cloning ability and viability, and the dual luciferase reporter gene assay was performed. Results: Cells in Dz group and D group were arranged in a regular manner, while cells in Dm group were tightly arranged with increased quantity. Besides, cells in Dy group were sparsely arranged and fractured with increased loss of nuclear membrane. The expression of Kras mRNA was the lowest in Dy group and the highest in Dm group, while the expression of miR-181a was the opposite. The transfection of miR-181a could reduce Kras activity (P0.05). Western blot showed that Kras protein expression in Dm group was higher than that in other groups (P