Abstract: Objective To investigate the effect of miR-200c-5p on malignant proliferation of human colorectal cancer cell line SW480. Methods Human colorectal cancer cell line SW480 was transfected with miR-200c-5p mimic/inhibitor and negative control agent respectively. The expression of miR-200c-5p was detected by qPCR, and the effects of miR-200c-5p on the proliferation activity and clonogenesis ability of colorectal cancer cells were detected by CCK-8 and foci formation experiment. Bioinformatics methods were used to analyze the differential target genes and related pathways of miR-200c-5p in human colorectal cancer. Results Transient transfection with miR-200c-5p mimic/inhibitor succeeded in high/low expression of miR-200c-5p (P＜0.05). The proliferation of cells with high expression of miR-200c-5p was significantly inhibited as compare to that of controls(P＜0.05). The clone-formation rate of miR-200c-5p cells with high expression was significantly lower than that of untransfected cells, while the clone-formation rate of miR-200c-5p cells with low expression was the opposite (P＜0.05). CXCL10, the target gene of miR-200c-5p, was significantly up-regulated in colorectal cancer, while C2orf72, ZC3H12C and DST were significantly down-regulated. The most significant KEGG pathways were “melanoma”, “microRNAs in cancer” and “bladder cancer”. Conclusions miR-200c-5p inhibits the proliferation and clonal formation of human colorectal cancer cell line SW480, which is related to the occurrence and progression of colorectal cancer.

Key words: colorectal cancer, miR-200c-5p, cell proliferation