microRNA-342-3p targets FOXQ1 to suppress the aggressive phenotype of nasopharyngeal carcinoma cells

BackgroundmicroRNA (miR)-342-3p is frequently dysregulated in human cancers. In the present study, we aimed to explore the expression, prognostic significance, and biological relevance of miR-342-3p in nasopharyngeal carcinoma (NPC).MethodsWe examined miR-342-3p expression in 79 paired NPC specimens and corresponding normal tissues and analyzed its prognostic impact on overall survival of NPC patients. Gain- and loss-of-function experiments were conducted to determine the biological roles of miR-342-3p.ResultsCompared with matched normal nasopharyngeal tissues, miR-342-3p was significantly downregulated in NPC (P=0.0038). Low miR-342-3p expression was significantly correlated with reduced overall survival (P=0.0084). Ectopic expression of miR-342-3p significantly suppressed proliferation, colony formation, and invasion of NPC cells. In contrast, depletion of miR-342-3p facilitated NPC cell proliferation and invasion. In vivo xenograft studies confirmed that overexpression of miR-342-3p restrained the growth of NPC xenograft tumors. Mechanistically, FOXQ1 served as a functional target of miR-342-3p. There was a significantly negative correlation between miR-342-3p and FOXQ1 expression (r=-0.487, P=0.004) in NPC specimens. Overexpression of FOXQ1 rescued the inhibitory effects of miR-342-3p on NPC cell growth and invasion.ConclusionsmiR-342-3p downregulation predicts poor prognosis in NPC patients and shows suppressive activity against NPC growth and invasion through repression of FOXQ1. Restoration of miR-342-3p may represent a potential therapeutic strategy for NPC.