miR-593 inhibits proliferation of colon cancer cells in vitro by down-regulating PLK1

MA Jinzhu; ZHU Yiping; WANG Zhen; ZAN Jiawei; CAO Long; FENG Zunyong; WANG Senlin; FAN Qian; YAN Liang

doi:10.12122/j.issn.1673-4254.2019.09.03

Abstract：Objective To explore the role of miR-593 in regulating the proliferation of colon cancer cells and the molecular mechanism.Methods Bioinformatics analysis identified PLK1 as the possible target gene of miR-593.Luciferase assay was employed to verify the binding between miR-593 and PLK1, and qRT-PCR and Western blotting were used to verify that PLK1 was the direct target gene of miR-593.CCK-8 assay was performed to test the hypothesis that miR-593 inhibited the proliferation of colon cancer cells by targeting PLK1.Results Luciferase assay identified the specific site of miR-593 binding with PLK1.Western blotting showed a significantly decreased expression of PLK1 in the colon cancer cells transfected with miR-593 mimics and an increased PLK1 expression in the cells transfected with the miR-593 inhibitor as compared with the control cells (P＜0.05).The results of qRT-PCR showed no significant differences in the expression levels of PLK1 among the cells with different treatments (P＞0.05).The cell proliferation assay showed opposite effects of miR-593 and PLK1 on the proliferation of colon cancer cells, and the effect of co-transfection with miR-593 mimic and a PLK1-overexpressing plasmid on the cell proliferation was between those in PLK1 over-expressing group and miR-593 mimic group.Conclusion miR-593 inhibits the proliferation of colon cancer cells by down-regulating PLK1 and plays the role as a tumor suppressor in colon cancer.