miR-214 inhibits invasion and migration via downregulating GALNT7 in esophageal squamous cell cancer

Previous studies verified that miR-214 is of great significance in the invasion and migration of a variety of cancers. It has been demonstrated that UDP-N-acetyl-alpha-D-galactosamine: polypeptide N-acetylgalactosaminyltransferase 7(GALNT7) is a putative target of miR-214. We performed this study to figure out howmiR-214 and GALNT7 play their roles in the invasion and migration of esophageal squamous cell carcinoma(ESCC). The expression of miR-214 was significantly downregulated in tumors compared to the corresponding non-tumor tissues while GALNT7 showed an opposite tendency. The low expression of miR-214 and the high expression of GALNT7 were found positively correlated with poor tumor differentiation (P = 0.004), tumor invasion (P = 0.013), and lymph nodemetastasis (P = 0.012) in ESCC patients. Functional study demonstrated that overexpression of miR-214 or knockdown of GALNT7 could weaken invasive and migratory ability in Eca109, TE1, and KYSE150. Moreover, tumorigenicity assay showed us mice injected with cells containing miR-214 mimic or GALNT7 small interfering RNA formed substantially smaller tumors than that in miR-214 inhibitor group. Consequently, we concluded that miR-214 shows potential to be a diagnostic marker and therapeutic target in ESCC.