miR-101 suppresses colon cancer cell migration through the regulation of EZH2

Background: colorectal cancer (CRC) is one of the most prevalent types of malignancies worldwide. The incidence of CRC is steadily increasing due to extended life expectancy and aging-related genetic and epigenetic abnormalities. Dysregulation of microRNAs (miRNAs) has been implicated in CRC development. Methods: the current study is a basic research study aimed at understanding the molecular mechanism of miR-101 in the pathogenesis of CRC using human samples in vivo and CRC cell lines in vitro. The miRNAs profile from human samples was analyzed by miRNA microarrays and the expression level of single miRNAs were confirmed by qRT-PCR. The validation of the direct target of miR-101 was performed by western blot assay. The cell mobility of CRC was assessed using the Transwell migration assay. Results: downregulation of miR-101 was identified in 39 human CRC tissues and CRC cell lines (HT29 and SW620) when compared to their counterpart control. We further confirmed that the enhancer of zeste homolog 2 (EZH2), a histone methyltransferase, is a direct target of miR-101. Overexpression of EZH2 promoted CRC cell line migration and this effect was inhibited by forcing the expression of miR-101. Thus, we conclude that miR-101 regulated colon cancer cell migration occurs at least partially, though targeting EZH2. Conclusion: our study suggests that miR-101 functions as a tumor suppressor in CRC, and miR-101 may be a potential therapeutic target for CRC treatment.