MicroRNA-183 inhibits apoptosis and promotes proliferation and invasion of gastric cancer cells by targeting PDCD4.

MicroRNA plays an important role in multiple processes of cancer development. Aberrant expression of miR-183 has been frequently reported in a variety of cancer types; however, the roles and mechanisms of miR-183 in gastric cancer are largely unknown. Here, we report that miR-183 is significantly up-regulated in human gastric tumor tissues compared to the adjacent normal tissues. Up-regulation of miR-183 is associated with advanced clinical stage, positive lymph node, deep stromal invasion, and distant metastasis in gastric cancer patients. We further demonstrated that miR-183 promotes gastric cancer cell growth in vitro by inhibition of apoptosis. Moreover, overexpression of miR-183 enhances gastric cancer cell migration and invasion. Mechanistically, we demonstrated that overexpression of miR-183 decreased, and inhibition of miR-183 increased the expression of PDCD4, a tumor suppressor, at both mRNA and protein levels. Taken together, our results suggest that miR-183 may modulate progression and metastatic potential of gastric cancer through inhibition of PDCD4 expression. miR-183 could serve as a potential biomarker for gastric cancer progression and a novel therapeutic target for gastric cancer treatment.