Transcriptional suppression of microRNA-27a contributes to laryngeal cancer differentiation via GSK-3β-involved Wnt/β-catenin pathway.

miR-27a regulates cell differentiation in a variety of diseases. However, whether and how miR-27a participates in laryngeal cancer cell differentiation remains unknown. Therefore, we explored role and molecular mechanism of miR-27a in laryngeal cancer differentiation in the study. We found that miR-27a expression was inversely correlated with laryngeal cancer differentiation degree based on the clinical pathological diagnosis of each patient. miR-27 asignificantly rescued differentiation and inhibited beta-catenin, LEF1, OCT4 and SOX2 in Wnt/beta-catenin pathway in all-transretinoic acid (ATRA)-induced laryngeal cancer cells. Bindings of RARa to miR-27a and miR-27a to GSK-3 beta were confirmed by ChIP and Luciferase reporter assays, respectively. In conclusion, miR-27a is a negative regulator in laryngeal cancer differentiation. RARa-mediated miR-27a transcriptional inactivation releases the inhibition of miR-27a on GSK-3 beta leading to laryngeal cancer differentiation through GSK-3 beta-involved Wnt/beta-catenin pathway, suggesting that miR-27a is a usefully therapeutic target at least in ATRA-induced laryngeal cancer differentiation.