Long non-coding RNA TUG1 promotes the proliferation of colorectal cancer cells through regulating Wnt/β-catenin pathway.

The long non-coding RNA taurine up-regulated gene 1 (TUG1) has been shown to be dysregulated in various types of malignant cancer; however, its underlying mechanism of action has not been fully elucidated. The present study aimed to investigate the biological role and clinical significance of TUG1 in the progression of colorectal cancer (CRC). A reverse transcription-quantitative polymerase chain reaction assay was used to evaluate TUG1 expression in tissues from patients with CRC. The effect of TUG1 on cell viability of CRC cells using MTT assay. The influence of TUG1 on tumorigenesis was monitored using an in vivo xenograft model. The status of the Wnt/β-catenin signaling pathway was evaluated using immunofluorescence, western blotting and luciferase reporter assays. The results demonstrated that the expression of TUG1 was positively associated with the pathological grade and clinical stage of CRC patients. Knockdown of TUG1 inhibited the proliferation of CRC cells and attenuated the activity of Wnt/β-catenin pathway in CRC cells. In addition, TUG1 knockdown inhibited the tumorigenicity in the in vivo CRC xenograft model, as well as the nuclear localization of β-catenin and downstream gene transcription. Taken together, the data of the present study highlighted the pivotal role of the TUG1-Wnt/β-catenin signaling pathway in CRC, which could be targeted to improve the therapeutic efficacy of CRC.