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bioRxiv · 10.1101/123141

LncRNA-TUG1/EZH2 Axis Promotes Cell Proliferation, Migration And The EMT Phenotype Formation Through Sponging miR-382

Abstract

Pancreatic carcinoma (PC) is the one of the most common and malignant cancer in the world. Despite many effort have been made in recent years, the survival rate of PC still remains unsatisfied. Therefore, investigating the mechanisms underlying the progression of PC might facilitate the development of novel treatments that improve patient prognosis. LncRNA Taurine Up-regulated Gene 1 (TUG1) was initially identified as a transcript up - regulated by taurine, siRNA - based depletion of TUG1 suppresses mouse retinal development, and the abnormal expression of TUG1 has been reported in many cancers. However, the biological role and molecular mechanism of TUG1 in pancreatic carcinoma (PC) still needs to be further investigated. In the current study, the expression of TUG1 in the PC cell lines and tissues was measured by quantitative real-time PCR (qRT-PCR), and loss-of-function and gain-of-function approaches were applied to investigate the function of TUG1 in PC cell. Online database analysis tools showed that miR-382 could interact with TUG1 and we found an inverse correlation between TUG1 and miR-382 in PC specimens. Moreover, dual luciferase reporter assay, RNA-binding protein immunoprecipitation (RIP) and applied biotin-avidin pulldown system further provide evidence that TUG1 directly targeted miR-382 by binding with microRNA binding site harboring in the TUG1 sequence. Furthermore, gene expression array analysis using clinical samples and RT-qPCR proposed that EZH2 was a target of miR-382 in PC. Collectively, these findings revealed that TUG1 functions as an oncogenic lncRNA that promotes tumor progression at least partially through function as an endogenous sponge by competing for miR-382 binding to regulate the miRNA target EZH2.

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BibTeXRIS

Zhao, L., Sun, H., Kong, H., Chen, Z., Chen, B., Zhou, M.. 2017-04-01. LncRNA-TUG1/EZH2 Axis Promotes Cell Proliferation, Migration And The EMT Phenotype Formation Through Sponging miR-382. https://doi.org/10.1101/123141

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