Osteopontin regulates growth and migration of human nasopharyngeal cancer cells.

Naspharyngeal carcinoma (NPC) is a common malignant tumor. Radiotherapy is the main treatment for patients with early-stage NPC. Some chemotherapeutic methods have been used to delay the progression of NPC during the later stages. Osteopontin (OPN), a secreted phosphoglycoprotein, has been shown to be involved in cell proliferation, migration and invasion in a variety of tumor models. However, the effect of OPN on the proliferation and migration activity of human NPC cells is still unknown. In this study, we detected the expression of OPN in NPC CNE-2 cells, and investigated the roles of OPN in CNE-2 cells. Our results show that the down-regulation of OPN inhibits the growth and migration of CNE-2 cells. Additionally, our results indicate that the cell number in the G2 phase can be regulated by OPN. We further demonstrate that OPN shRNA down-regulates the expression of MMP-2 and MMP-9, and that OPN overexpression up-regulates the expression of MMP-2 and MMP-9.