Abstract
OBJECTIVE: DNA methyltransferases (DNMTs) take on a relevant role in epigenetic control of cancer proliferation and cell survival. However, the molecular mechanisms underlying the establishment and maintenance of DNA methylation in human cancer remain to be fully elucidated. This study was to investigate that how DNMT1 affected the biological characteristics of colorectal cancer (CRC) cells via modulating methylation of microRNA (miR)-152-3p and thymosin β 10 (TMSB10) expression. METHODS: DNMT1, miR-152-3p, and TMSB10 expression, and the methylation of miR-152-3p in CRC tissues and cells were detected. SW-480 and HCT-116 CRC cells were transfected with DNMT1 or miR-152-3p-related sequences or plasmids to explore their characters in biological functions of CRC cells. The binding relationship between DNMT1 and miR-152-3p and the targeting relationship between miR-152-3p and TMSB10 were analyzed. The tumor growth was also detected in vivo. RESULTS: Upregulated DNMT1, TMSB10, reduced miR-152-3p, and methylated miR-152-3p were detected in CRC tissues and cells. Silenced DNMT1 or upregulated miR-152-3p reduced TMSB10 expression and suppressed CRC progression and tumor growth. Moreover, elevated DNMT1 could reverse the effect of miR-152-3p upregulation on CRC development and tumor growth. DNMT1 maintained methylation of miR-152-3p. TMSB10 was the direct target gene of miR-152-3p. CONCLUSION: The study highlights that silenced DNMT1 results in non-methylated miR-152-3p to depress TMSB10 expression, thereby inhibiting CRC development, which provides a new approach for CRC therapy.