miR-203 Regulates Proliferation and Apoptosis of Colorectal Cancer Cells Through Targeting DJ-1

Objective: To assess whether miR-203 regulates DJ-lexpression, affects colorectal cancer cells through PTEN-PI3K/AKT signaling. Methods: Colorectal cancer (CRC) tissues and adjacent tissues were collected followed by analysis of the level of miR-203, DJ-1 and PTEN. miR-203 and DJ-1 level was measured in HCT116, SW480 and normal colorectal cell NCM460. miR-203 mimic or miR-NC was transfected into HCT116 or SW480 cells followed by measuring the level of miR-203, DJ-1, PTEN, p-AKT as well as cell apoptosis and proliferation. Results: Compared with tumor adjacent tissues, tumor tissues showed significantly lower level of miR-203 and PTEN, and higher level of DJ-1. There is a targeted relationship between miR-203 and DJ-1. Compared with NCM460 cell, HCT116 and SW480 cells displayed significantly lower miR-203 level and higher DJ-1 expression. miR-203 mimic significantly reduced DJ-1 and p-AKT level, increased PTEN expression, cell apoptosis and inhibited cell proliferation. Conclusion: Lower miR-203 and higher DJ-1 level is found in CRC patients. Upregulation of miR-203 inhibits DJ-1 expression, increases PTEN expression, impairs PI3K/AKT signaling, inhibits CRC cell proliferation and promotes apoptosis.