LncRNA CACS15 regulates tongue squamous cell carcinoma cell behaviors and predicts survival

The involvement of lncRNA CASC15 in several types of cancers has been reported, while its role in tongue squamous cell carcinoma (TSCC) is unknown. Our study aimed to investigate the clinical potentials of lncRNA CASC15 in TSCC.

The expression of CASC15 and miR-124 in tissue samples from TSCC patients and TSCC cell lines was analyzed by qPCR. Overexpression experiments were performed to analyze the interactions between CASC15 and miR-124. Survival analysis was performed to analyze the prognostic values of CASC15 and miR-124 for TSCC. Transwell assays were performed to analyze cell invasion and migration.

We found that CASC15 was upregulated, while miR-124 was downregulated in TSCC tissues than in non-cancer tissues of TSCC patients. CASC15 and miR-125 expression was not significantly different among patients with different clinical stages, and patients with high level of CASC15 and low level of miR-125 showed low overall survival rate. CASC15 and miR-124 were inversely correlated in TSCC tissues, and CASC15 overexpression in TSCC cells resulted in downregulation of miR-124. In contrast, overexpression of miR-124 showed no significant effect on CASC15 expression. CASC15 overexpression resulted in the increased, while miR-124 overexpression resulted in the decreased migration and invasion rates of TSCC cells.

CASC15 and miR-124 predict TSCC patients' survival and CASC15 may downregulate miR-124 to inhibit TSCC cell migration and invasion. The study was approved by Ethics Committee of The first Affiliated Hospital of Jinzhou Medical University (20103548FAHJMU).