MiR-506 Suppresses Tumor Proliferation and Invasion by Targeting FOXQ1 in Nasopharyngeal Carcinoma

MiRNAs are small noncoding RNAs that play important roles in various biological processes including tumorigenesis. However, little is known about the expression and function of miR-506 in nasopharyngeal carcinoma (NPC). In this study, we showed that miR-506 was downregulated in nasopharyngeal carcinoma (NPC) cell lines and tissues. Ectopic expression of miR-506 dramatically suppressed cell proliferation, colony formation and invasion. Moreover, we identified the Forkhead box Q1 (FOXQ1) gene as a novel direct target of miR-506. MiR-506 exerts its tumor suppressor function through inhibition of the FOXQ1, which was involved in tumor metastasis and proliferation in various cancers. Furthermore, the expression of FOXQ1 is up-regulated in NPC cell lines and tissues. Taken together, our results indicate that miR-506 functions as a tumor suppressor miRNA in NPC and that its suppressive effects are mediated chiefly by repressing FOXQ1 expression.