MiR-203 Affects Proliferation, Apoptosis and Cisplatin Resistance of Gastric Cancer Cells Through DJ-1-PTEN-PI3K/AKT Pathway

Abstract

DJ-1 negatively regulates phosphatase and tensin homolog gene (PTEN). Abnormal miR-203 expression is associated with gastric cancer. Bioinformatics analysis showed a targeting relationship between miR-203 and DJ-1 3′-UTR. Our study evaluated the role of miR-203 gastric cancer cell proliferation, apoptosis, and cisplatin (DDP) resistance. The CDDP-resistant cell line SGC7901/CDDP was established and divided into miR-NC group and miR-203 mimic group followed by detecting DJ-1, PTEN and p-AKT expression, and cell apoptosis and proliferation by flow cytometry. There was a targeted relationship between miR-203 and DJ-1 mRNA. miR-203 expression in SGC7901/CDDP cells was significantly reduced compared with SGC7901 cells with elevated DJ-1 mRNA and protein level. Compared with miR-NC group, DJ-1 and p-AKT in SGC7901/CDDP cells was significantly downregulated in miR-203 mimic transfection group, while PTEN expression was significantly increased, cell apoptosis was increased, and proliferation and CDDP resistance were reduced. Decreased miR-203 and increased DJ-1 level is associated with gastric cancer drug resistance. Elevated miR-203 can downregulate DJ-1, affect the activity of PTEN-PI3K/AKT pathway, inhibit gastric cancer cell proliferation, promote cell apoptosis, and enhance the drug sensitivity to CDDP.