Increased miR-222 in H. pylori-associated gastric cancer correlated with tumor progression by promoting cancer cell proliferation and targeting RECK

Little is known about the potential role of microRNAs (miRNAs) in the carcinogenesis of gastric cancer induced by Helicobacter pylori (H. pylori). Here, we showed that microRNA-222 (miR-222) was up-regulated in H. pylori-infected gastric mucosa and gastric cancer. Ectopic expression of miR-222 promoted cell proliferation and colony formation in vitro. Mechanistically, we identified RECK as a novel target of miR-222, and also confirmed their relationship by the inverse correlation of mRNA expression ex vivo. Furthermore, we found that RNA interference silencing of RECK can mimic the oncogenic effects of miR-222. Collectively, H. pylori may function as an initiator in the process of carcinogenesis by up-regulating miR-222, which further participates in the progression of cancer by promoting proliferation and inhibiting RECK.

► miR-222 is up-regulated both by H. pylori infection and in gastric cancer.
► Over-expression of miR-222 promotes cell proliferation and colony formation.
► RECK is a novel target of miR-222 and inversely correlated with miR-222.
► RECK is involved in miR-222-regulated proliferation in gastric cancer cells.