The lncRNA PVT1 Contributes to the Cervical Cancer Phenotype and Associates with Poor Patient Prognosis

The plasmacytoma variant translocation 1 gene (PVT1) is an lncRNA that has been designated as an oncogene due to its contribution to the phenotype of multiple cancers. Although the mechanism by which PVT1 influences disease processes has been studied in multiple cancer types, its role in cervical tumorigenesis remains unknown. Thus, the present study was designed to investigate the role of PVT1 in cervical cancer in vitro and in vivo. PVT1 expression was measured by quantitative PCR (qPCR) in 121 invasive cervical carcinoma (ICC) samples, 30 normal cervix samples, and cervical cell lines. Functional assays were carried out using both siRNA and LNA-mediated knockdown to examine PVT1's effects on cervical cancer cell proliferation, migration and invasion, apoptosis, and cisplatin resistance. Our results demonstrate that PVT1 expression is significantly increased in ICC tissue versus normal cervix and that higher expression of PVT1 correlates with poorer overall survival. In cervical cancer cell lines, PVT1 knockdown resulted in significantly decreased cell proliferation, migration and invasion, while apoptosis and cisplatin cytotoxicity were significantly increased in these cells. Finally, we show that PVT1 expression is augmented in response to hypoxia and immune response stimulation and that this lncRNA associates with the multifunctional and stress-responsive protein, Nucleolin. Collectively, our results provide strong evidence for an oncogenic role of PVT1 in cervical cancer and lend insight into potential mechanisms by which PVT1 overexpression helps drive cervical carcinogenesis.