MicroRNA-449b-5p suppresses cell proliferation, migration and invasion by targeting TPD52 in nasopharyngeal carcinoma

Abstract

Abstract Nasopharyngeal carcinoma (NPC) is an important type of head and neck malignant cancer with geographical distribution. MicroRNA-449b-5p (miR-449b-5p) is related to the development of various cancers, while its function in NPC remains unknown. The present study aimed to investigate the role and target gene of miR-449b-5p in NPC. Expressions of miR-449b-5p in NPC cell lines and clinical tissues were detected by quantitative real-time polymerase chain reaction (qRT-PCR). Cell proliferation was determined by MTT and colony formation assays. Migration and invasion abilities after different treatment were evaluated by wound healing and Transwell assays, respectively. Dual-luciferase reporter assay was performed to explore the relationship between miR-449b-5p and tumour protein D52 (TPD52). TPD52 expression was determined by qRT-PCR and western blot assay. miR-449b-5p was significantly downregulated in NPC cell lines and clinical tissues than the matched control. Overexpression of miR-449b-5p inhibited proliferation, migration and invasion of NPC cells. Dual-luciferase reporter assay indicated that miR-449b-5p directly targeted TPD52. Furthermore, shRNA-mediated downregulation of TPD52 rectified the promotion of cell migration and invasion by miR-449b-5p inhibition. In conclusion, the present study suggests that miR-449b-5p, as a novel tumour-suppressive miRNA against NPC, inhibits proliferation, migration and invasion of NPC cells via inhibiting TPD52 expression.