MicroRNA-200c binding to FN1 suppresses the proliferation, migration and invasion of gastric cancer cells.

We aimed to investigate the effects of miR-200c binding to fibronectin 1 (FN1) on proliferation, migration and invasion of gastric cancer (GC) cells. A total of 52 GC tissues and their corresponding normal adjacent tissue samples were collected. Then, miR-200c and FN1 were tested using quantitative real-time RT-PCR in the clinical specimens and GC cells, while immunohistochemistry and western blotting assay were carried out to detect FN1 expressions. Dual luciferase reporter gene assay was used to assess the effect of miR-200c on the luciferase activity of FN1 3'UTR. BGC-823 cells were transfected with miR-200c mimics, miR-200c inhibitors and FN1 siRNA, respectively. The effects of miR-200c inhibitors and FN1 siRNA on cellular proliferation, migration and invasion were detected through MTT assay and Transwell assay. Compared to normal tissues and cells, miR-200c was significantly down-regulated and FN1 was significantly up-regulated (P<0.01). Dual luciferase reporter gene assay showed that miR-200c could specifically bind to the 3'-UTR of FN1 and significantly repress the luciferase activity (P<0.01). Both mRNA and protein expressions of FN1 were decreased significantly in GC cells when miR-200c was over expressed. The proliferation, migration and invasion of GC cells could be suppressed by over-expression of miR-200c or down-regulation of FN1. In conclusion, miR-200c was significantly down-regulated in both GC tissues and cell lines, while FN1 presented the opposite trends. Besides, miR-200c inhibited the proliferation, migration and invasion of GC cells through binding to FN1.