MicroRNA-125b expression in gastric adenocarcinoma and its effect on the proliferation of gastric cancer cells.

MicroRNAs exert regulatory effects on a number of genes, thereby contributing to both physiological and pathological processes. The functions of microRNAs in tumorigenesis are becoming increasingly clear. In the present study, we investigated the role of microRNA-125b (miR‑125b), previously implicated in prostate and breast cancer, in gastric cancer, particularly regarding proliferation and apoptosis of gastric cancer cells. The expression of miR‑125b was measured in 50 samples of gastric cancer tissues and corresponding para-cancerous tissues by real-time PCR. The levels of miR‑125b expression in the gastric cancer tissues were significantly higher compared to the adjacent normal tissues (P<0.05). To begin to understand how the increased expression of miR‑125b may promote gastric cancer, the miR‑125b mimic was transfected into the gastric cancer cell line, HGC‑27, for the determination of proliferation (CCK8) and apoptosis (Annexin V) by flow cytometry. The results demonstrated that the proliferation significantly increased and apoptosis significantly decreased in the HGC‑27 cells following transfection with the miR‑125b mimic, compared to the untreated and scramble‑treated controls (P<0.05). Thus, miR‑125b may act as an oncogene in gastric cancer by dysregulating gastric cell proliferation and apoptosis.