The effects of microRNA-98 inhibits cell proliferation and invasion by targeting STAT3 in nasopharyngeal carcinoma.

MicroRNA-98 (miR-98) is downregulated in many tumors, and is closely related to tumor progression. In addition, it shows anticarcinogenic functions in various tumor. However, few study show that the biological function and regulatory mechanisms of miR-98 in nasopharyngeal carcinoma (NPC) progression. The identification and its target genes which regulate by dysregulated miRNAs may strengthen our understanding of the molecular mechanisms of NPC. In this study, we observe that miR-98 is not only significantly reduced in NPC tissues, but also decreased markedly in NPC cell lines. Moreover, silencing miR-98 expression studies not only show miR-98 induced cell proliferation, migration and invasion in vitro, but also it promoted xenograft tumor growth in vivo in NPC. Furthermore, western blot assay was used to detected the level of STAT3 protein and we demonstrate that miR-98 regulate cells poliferation, migration and invasion through directly modulating functional target STAT3 by directly binding its 3'-UTR. These findings illustrate miR-98 as a anticarcinogenic functions through targeting STAT3, the miR-98/STAT3 pathway gives new clues for understanding NPC carcinogenesis and provides novel therapeutic targetsfor NPC.