MIR-491-5p suppresses cell growth and invasion by targeting Notch3 in nasopharyngeal carcinoma

Abstract

MicroRNAs (miRNAs) have critical roles in the progression of nasopharyngeal carcinoma (NPC),a highly invasive and metastatic cancer that is widely prevalent in Southern China. miR-491-5p has been implicated in multiple types of cancer; however,its biological role and underlying mechanism in NPC have not been fully explored. In the present study,we found that miR-491-5p was downregulated in NPC tissues and cell lines compared with the corresponding normal counterparts. Overexpression of miR-491-5p significantly inhibited cell proliferation,migration and invasion in vitro and suppressed tumor growth in vivo. Using miRNA target prediction algorithms and reporter assays,we showed that miR-491-5p suppressed Notch3 expression both at the mRNA and protein level through directly targeting the 3' untranslated region (3'-UTR) of Notch3 mRNA. Overexpression of Notch3 significantly reversed the tumor-suppressive effects of miR-491-5p. Taken together,the present study reveals a mechanistic link between miR-491-5p and Notch3 in the pathogenesis of NPC and that miR-491-5p has potential as a therapeutic target for NPC.