LncRNA-PVT1 promotes pancreatic cancer cells proliferation and migration through acting as a molecular sponge to regulate miR-448

The identification and characterization of long non-coding RNAs (lncRNAs) in diverse biological process has currently developed rapidly. LncRNA-PVT1, located adjacent to the MYC locus on chromosomal region 8q24, has been reported to be associated with many biological processes. However, the function and mechanism of PVT1 in pancreatic carcinoma (PC) is poorly understood. In this present study, we first measured the level of PVT1 in the PC cell lines and tissues by quantitative real-time PCR (qRT-PCR), and then employed loss-of-function and gain-of-function approaches to explore the association between PVT1 expression levels and PC cell proliferation/migration ability. Furthermore, bioinformatics analysis was utilized to show that PVT1 contains binding site for miR-448 and an inverse correlation between PVT1 and miR-448 was obtained in PC specimens. Additionally, dual luciferase reporter assay, RNA-binding protein immunoprecipitation (RIP) and applied biotin-avidin pulldown system were applied to further confirm that PVT1 directly bind with microRNA binding site harboring in the PVT1 sequence. Then, SERBP1 was identified as a target of miR-448 according to the gene expression array analysis of PC clinical samples. Together, we revealed that PVT1 functions as an endogenous "sponge" by competing for miR-448 binding to regulate the miRNA target SERBP1 and, therefore, promotes the proliferation and migration of PC cells.