MiR-613 suppressed the laryngeal squamous cell carcinoma progression through regulating PDK1.

MicroRNAs (miRNAs) are aberrantly expressed in several tumors and play important role in tumorigenesis. However, little is known about the role of miR-613 in laryngeal squamous cell carcinoma (LSCC). We determined the expression of miR-613 in a panel of 30 LSCC specimens. Compared with the adjacent normal samples, 20 cases of LSCC tissues exhibited decreased expression of miR-613. The average expression of miR-613 in LSCC tissues was lower than in normal samples. Moreover, we demonstrated that exogenous expression of miR-613 suppressed LSCC cell proliferation, invasion, and blocked G1/S phase transition. We identified that 3-phosphoinositide-dependent protein kinase-1 (PDK1) was a direct target gene of miR-613 in LSCC cell. Overexpression of miR-613 suppressed PDK1 expression in LSCC cell. Furthermore, we demonstrated that PDK1 was upregulated in LSCC tissues. MiR-613 expression was inversely correlated with the expression of PDK1 in LSCC tissues. Moreover, we showed that PDK1 was involved in the miR-613-mediated cancer suppression of LSCC cell. These results suggested that miR-613 played as a tumor suppressor gene in LSCC partly by inhibiting PDK1 expression.