LncRNA PVT1 overexpression is a poor prognostic biomarker and regulates migration and invasion in small cell lung cancer.

PVT1 has been suggested as playing important roles in diverse biological processes including tumorigenesis. However, the clinical significance and biological function of PVT1 in small cell lung cancer (SCLC) is still unclear. The purpose of this study is to identify the role of PVT1 in SCLC. The expression of PVT1 was examined in SCLC tissues and cell lines through real-time PCR. Meanwhile, the relationship of PVT1 expression levels with clinical characteristics of 120 SCLC patients was analyzed. Univariate and multivariate analyses were performed to determine the association between PVT1 expression and prognosis of SCLC patient. The biological function of PVT1 on tumor cell growth and mobility were explored through MTT, colony formation, Transwell migration and invasion assays in vitro. In our results, PVT1 expression was markedly higher in SCLC tissues and cell lines than in normal lung tissues and normal bronchial epithelial cell lines (both P<0.001). High levels of PVT1 were positively associated with the status of clinical stage (Limited vs. Extensive, P<0.001), lymph node metastasis (No vs. Yes, P<0.001), and distant metastasis (No vs. Yes, P<0.001) in SCLC patients. Patients with higher PVT1 expression had a significantly poorer overall survival time than did patients with low PVT1 expression (P<0.001). Multivariate analysis showed that PVT1 overexpression was an independent prognostic indicator (P=0.024) for the survival of patients with SCLC. Knocking down PVT1 expression significantly inhibited the SCLC cell migration and invasion in vitro (both P<0.001), but has no effect on the growth of SCLC cells (both P>0.05). In conclusion, PVT1 could serve as a new biomarker and a potential therapeutic target for SCLC patients.