MicroRNA-342 inhibits cell proliferation and invasion in nasopharyngeal carcinoma by directly targeting ZEB1.

Nasopharyngeal carcinoma (NPC) is prevalent in Africa and East Asia, particularly in the southern areas of China. Previous data has demonstrated that microRNAs (miRNAs/miRs) may be involved in the formation and progression of NPC. The deregulation of miR-342 has been identified in multiple types of cancer. However, to the best of our knowledge, there are no data concerning miR-342 in NPC. The present study aimed to measure miR-342 expression in NPC, and to investigate its roles in NPC initiation and progression, in addition to the underlying molecular mechanisms. miR-342 was significantly downregulated in NPC tissues and cell lines. Low miR-342 expression was associated with distant metastasis and tumor node metastasis stage in patients with NPC. The restoration of the expression of miR-342 suppressed cell proliferation and invasion of NPC in vitro. In addition, ZEB1 was identified as a direct target gene of miR-342 in NPC. Downregulation of ZEB1 mimicked the tumor-suppressive roles of miR-342 in NPC. Taken together, the present study identified that miR-342 directly targeted ZEB1 to inhibit NPC cell growth and invasion, which may provide a novel therapeutic target for the treatments of patients with this malignancy.