MiR-216a-5p targets TCTN1 to inhibit cell proliferation and induce apoptosis in esophageal squamous cell carcinoma.

Background: MiR-216a-5p has been reported to be associated with several tumors, including prostate cancer and melanoma. However, its expression level and potential role in esophageal squamous cell carcinoma (ESCC) remain uncertain.

Results: Here, we found that miR-216a-5p expression was significantly down-regulated in clinical ESCC tissues and cells. Functional assays were performed to evaluate the biological effects of miR-216a-5p on cell proliferation and cell apoptosis by CCK-8 assay and flow cytometry in ESCC cell lines, EC9706 and TE-9. The results showed that miR-216a-5p overexpression repressed cell proliferation and induced cell apoptosis. Through bioinformatics prediction and luciferase reporter assay, we revealed that miR-216a-5p could directly target tectonic family member 1 (TCTN1). Moreover, TCTN1 was obviously suppressed by miR-216a-5p overexpression. In addition, TCTN1 expression was significantly increased and inversely correlated with the levels of miR-216a-5p in ESCC tissues. More importantly, down-regulation of TCTN1 imitated, while restoration of TCTN reversed the effects of miR-216a-5p on cell proliferation and apoptosis. At the molecular level, we further found that TCTN1 overexpression reversed the effects of miR-216a-5p transfection on the expression of PCNA, Bcl-2 and Bad.

Conclusions: Our results demonstrate that miR-216a-5p might serve as a tumor suppressor in ESCC cells through negatively regulating TCTN1 expression, indicating the possibility that miR-216a-5p and TCTN1 might be attractive targets for ESCC therapeutic intervention.