Upregulation of miR-370 contributes to the progression of gastric carcinoma via suppression of FOXO1.

FOXO1 is downregulated in a number of cancers. However, the underlying mechanisms are poorly understood. In this study, we report that the expression of miR-370 was upregulated in gastric cancer cell lines and gastric cancer tissues. Overexpression of miR-370 in gastric cancer cells promoted the cell proliferation and anchorage-independent growth, while silencing of miR-370 showed opposite effects. miR-370-induced proliferation was correlated with the downregulation of cyclin-dependent kinase inhibitors, p27(Kip1) and p21(Cip1), and the upregulation of the cell cycle regulator cyclin D1. Furthermore, we identified that FOXO1 is the functional target of miR-370. Restored expression of FOXO1 together with miR-370 strongly abrogated miR-370-induced cell proliferation. Taken together, our results revealed a novel mechanism of FOXO1 suppression mediated by miR-370 in gastric cancer.