miR-194 inhibits gastric cancer cell proliferation and tumorigenesis by targeting KDM5B.

OBJECTIVE MicroRNAs play critical roles in regulating gene expression and various cellular processes in human cancer malignant progression. The aim of the present study was to examine the expression pattern of miR-194 in gastric cancer (GC) and its biological role in tumor progression. MATERIALS AND METHODS Using quantitative RT-PCR, we detected miR-194 expression in GC cell lines and primary tumor tissues. The proliferation, migration, and invasion assays were performed to investigate the effect of miR-194 on the GC cells. The target of miR-194 was predicted by TargetScan and confirmed by luciferase reporter assay. KDM5B expression was detected by Western blot. RESULTS miR-194 was significantly down-regulated in GC tissues and cell lines. Over-expression of miRNA-194 could inhibit GC cell proliferation, migration, and invasion in vitro. Also, miR-194 inhibited tumor growth and progression in vivo. Dual luciferase-based reporter assay indicated direct regulation of KDM5B by miR-194. CONCLUSIONS Our findings suggested that miR-194 directly targeted KDM5B and thereby acted as a tumor promoter in GC progression.