MicroRNA-92a promotes metastasis of nasopharyngeal carcinoma by targeting the PTEN/AKT pathway

MicroRNAs have been confirmed to be a group of important regulators during the pathogenesis of nasopharyngeal carcinoma (NPC). This study confirmed that the expression of microRNA-92a (miR-92a) was significantly upregulated in NPC as compared to noncancerous nasopharyngeal epithelial tissues. Furthermore, high expression of miR-92a was observed in all NPC cell lines, especially in high metastatic cell lines. Clinical analysis indicated that high expression of miR-92a was associated with adverse clinicopathological features including the advanced tumor-node-metastasis stage and distant metastasis, and conferred poor prognosis of patients. In vitro assays showed that miR-92a overexpression potentiated the migration and invasion of 6-10B cells, and miR-92a silencing reduced the number of migrated and invaded 5-8F cells. Phosphatase and tensin homolog (PTEN) was confirmed as a direct downstream target of miR-92a in NPC cells. Otherwise, alteration of miR-92a expression regulated PTEN/AKT pathway in NPC cells. Mechanistically, miR-92a exerted its promoting effects on the metastatic behaviors of NPC cells through suppressing PTEN/AKT pathway. Taken together, this study demonstrates that miR-92a is a promising prognostic biomarker for patients with NPC, and may be a potential therapeutic target to prevent the metastasis of NPC.