MiR-431 inhibits colorectal cancer cell invasion via repressing CUL4B.

OBJECTIVE: To detect the expression of microRNA-431 (miR-431) in epithelial- mesenchymal transition (EMT) in colorectal carcinoma and investigate its effects on the migration of colorectal cancer cells. PATIENTS AND METHODS: MiR-431 expressions in colorectal cancer tissues and adjacent tissues were examined via Real-time quantitative reverse transcriptase-polymerase chain reaction (RT-PCR). The expression levels of cullin- 4B (CUL4B) and EMT-related protein were evaluated by Western blotting assay. The invasive ability of the cells was examined via transwell method. RESULTS: The expression level of miR-431 in colorectal cancer tissues was lower than that in adjacent tissues (p < 0.05). After colorectal cancer cell line was transfected with miR-431 mimics, the expression level of e-cadherin was increased in the cells, and the expression levels of n-cadherin, vimentin, fibronectin (FN), and snail were reduced (p< 0.05). The migration ability of colorectal cancer cells with miR-431 overexpression was significantly decreased. Moreover, the reverse effect was observed in cells transfected with miR-431 inhibitors. CONCLUSIONS: The low expression of miR431 in colorectal cancer patients is involved in the development of colorectal cancer by promoting the migration of colorectal cancer cells.