Mir-204 Regulates the EMT by Targeting Snai1 to Suppress the Invasion and Migration of Gastric Cancer

miR-204 was found to be downregulated in gastric cancer (GC) tissues, and the effect of miR-204 function on gastric cancer remains as a mystery. Therefore, this study was aimed at investigating the potential role of miR-204 involved in GC progression. Tissues collected from 60 gastric cancer patients were selected as the case group, while the matched normal paracancer tissues as controls. miR-204 expression levels in tissues and GC cells were detected using real-time fluorescent quantitative PCR. Luciferase assay was adopted to validate the interaction between potential gene targets and miR-204. Transwell assay was performed to evaluate the metastasis of GC cells. By building the epithelial-mesenchymal transition (EMT) model in vitro through the addition of transforming growth factor beta 1 (TGF-β1), expressions of miR-204 and snai1 in the EMT model together with their respective effects on EMT were evaluated. miR-204 was significantly downregulated in GC tissues and invasive GC cells (P < 0.05). The over-expression of miR-204 or downregulation of snai1 could significantly inhibit the metastasis and invasion of GC cells both in vitro and in vivo. The upregulated miR-204 expression or inhibited snai1 expression could suppress the EMT process in EMT in vitro models. Our study provided evidence that miR-204 may suppress the metastasis and invasion of GC cells through the regulation of the EMT process by targeting snai1.