Nasopharyngeal carcinoma (NPC) is a malignant tumor with high invasive and metastatic properties. Dysregulation of miRNAs may contribute to disease progression by targeting disease-related genes. In this study we aimed to elucidate the role and function of aberrantly expressed miRNA in NPC tumorigenesis. We found that miR-1178-3p was highly expressed in NPC tissues. Overexpression of miR-1178-3p promoted the proliferation, migration and invasion of NPC cells in vitro. In contrast, knocking down endogenous miR-1178-3p by miRNA-specific inhibitor significantly suppressed the above phenotypes. Moreover, miR- 1178-3p was shown to negatively regulate serine/threonine-protein kinase 4 (STK4), an NPC-related tumor suppressor gene, in the post-transcriptional level. Furthermore, STK4 overexpression abolished miR-1178- 3p-induced cell proliferation, migration and invasion through STK4-mediated dephosphorylation of AKT. Our results indicate that miR-1178-3p acts as an oncomiRNA in NPC by suppressing STK4 expression, and inhibition of miR-1178-3p may become a therapeutic potential for NPC.
Keywords: AKT signaling; STK4; miR-1178-3p; nasopharyngeal carcinoma.