mir-493 suppresses the proliferation and invasion of gastric cancer cells by targeting rhoc

objective(s):mirnas have been proposed to be key regulators of tumorigenesis, progression and metastasis. however, their effect and prognostic value in gastric cancer is still poorly known. materials and methods: gastric cancer cell lines were cultured. tissue samples obtained from 36 gastric cancer patients were used for quantitative real-time pcr (qrt-pcr) analysis. the tissue microarrays (tmas) consisted of 126 cases of gastric carcinoma that were used for in situ hybridisation (ish). lentivirus plasmids were co-transfected into 293ft cells. cell migration was examined using wound-healing assays. statistical analyses were performed using spss16.0 software. results: in this study, we found that the expression levels of mir-493 were strongly down-regulated in gastric cancer and were associated with clinical stage and the presence of lymph node metastases. moreover, mir-493 might independently predict os and rfs in gastric cancer. we further found that up-regulation of mir-493 inhibited the proliferation and metastasis of gastric cancer cells, in vitro and in vivo. in addition, mir-493 directly targeted rhoc, which resulted in a marked reduction of the expression of mrna and protein. this effect, in turn, led to a decreased ability of growth, invasion and metastasis in gastric cancer cells. conclusion: taken together, our findings demonstrate that mir-493 is important for gastric cancer initiation and progression and holds promise as a prognostic biomarker to predict survival and relapse in gastric cancer. it is also a potential therapeutic tool to improve clinical outcomes in this disease.