Objective To explore the effects of down-regulated PVT1 on the proliferation,migration and invasion of nasopharyngeal cancer(NPC)C666-1 cells. Methods Expression of PVT1 in NPC cell lines was de-tected by real-time RT-PCR. The effects of PVT1 silencing on cell proliferation were detected using MTT assay. Transwell assay was performed to assess the effect of down-regulated PVT1 on C666-1 cells migration and invasion. Protein level of N-cadherin,Vimentin and E-cadherin were determined by qRT-PCR and Western blot. Results Expression of PVT1 was significantly increased in seven NPC cell lines. Expression of PVT1 was reduced compared to the control group after the siPVT1 transfection. C666-1 cell proliferation was inhibited as compared with siNC group after transfection. The number of migration and invasion cells were significantly reduced while down-regulat-ed PVT1 expression. E-cadherin expression was upregulated while N-cadherin and Vimentinafter was downregulat-ed after PVT1 silencing. Conclusions Downregulation of PVT1 in C666-1 cells via siPVT1 transfection can inhib-it cell growth,migration and invasion,as well as reverse epithelial-mesenchymal transition. PVT1 may serve as a biomarker or even a therapeutic target for NPC.