MicroRNA-18a promotes proliferation and metastasis in oral squamous cell carcinoma via targeting KLF4.

Oral squamous cell carcinoma (OSCC) is a complex disease with extensive genetic and epigenetic defects, including microRNA deregulation. The aims of the present study were to explore the regulatory mechanism of microRNA-18a in OSCC cells proliferation and metastasis. Quantitative real-time PCR (qRT-PCR) was used to detect the expression level of miR-18a and KLF4 mRNA in OSCC tissues and cell lines (SCC-25, CAL-27, Tca-8113). Western-blot analysis was used to validate expression of KLF4 protein. CCK-8 assay was performed to e validate the proliferous ability of human OSCC cells. Transwell assays were performed to determine the migratory and invasive abilities of OSCC in vitro. Dual-luciferase reporter assay, qRT-PCR and Western-blot were used to confirm that miR-18a regulates KLF4 expression in OSCC. miR-18a was significantly up-regulated in human OSCC cell lines (SCC-25, CAL-27, and Tca-8113) and clinical OSCC specimens. miR-18a over-expression markedly promoted human OSCC cell proliferation, invasion, migration in vitro. Bioinformatics analysis made a prediction that KLF4 was the candidate target gene of miR-18a, and western blotting confirmed the negative correlation between miR-18a and KLF4. Additionally, KLF4 was negatively associated with miR-18a in OSCC and abnormal expression of KLF4 attenuated miR-18a-mediated promotion in cell proliferation. In conclusmiR-18a p ion, remoted OSCC proliferation, migration and invasion abilities and suppressed the expression of, KLF4. This newly identified miR-18a/KLF4 axis may provide new insight into the pathogenesis and offers a potential target for OSCC therapy.