Abstract:

Objective Radiotherapy is the standard treatment for nasopharyngeal carcinoma （NPC）. Increasing evidence shows that long non⁃coding RNA （lncRNAs） plays an important role in regulating cell radiosensitivity. However，the role of TUG1 in radiation resistance of NPC has not been studied. This study is to perform pan⁃cancer analysis of TUG1，and to evaluate its effect on biological behavior and radiosensitivity of NPC. Methods Expression and prognostic value of TUG1 in pan⁃cancer were detected based on TCGA database. qPCR was used to detect the expression of TUG1 in NPC tissues and NPC cell lines. CNE⁃1 and CNE⁃2 cells were trans⁃ fected with TUG1 siRNA or negative control siRNA. The proliferation，invasion and migration of NPC cells were detected by MTS，transwell and scratch test. The radiosensitivity of cells was measured by cell clone formation. The cell cycle and apoptosis were detected by flow cytometry. Results Analysis based on TCGA database showed that the expression of TUG1 was up⁃regulated in 12 cancer types. The increased expression of TUG1 was associated with poor prognosis in many types of cancers. In vitro studies showed that TUG1 was also significantly up⁃regulated in NPC cell lines and tissues. There was a significant association between TUG1 overexpression and worse TNM stage. Moreover，high expressionof TUG1 in NPC was determined to be a strongpredictor of short overall survival. Further investigation found that knockdown of TUG1 repressed proliferation，migration and invasion，promoted apoptosis， and improved radiosensitivity. Conclusion Our results reveal the important role of TUG1 in many types of cancers and it is related to the poor prognosis of NPC. TUG1may serve as novel targets for NPC therapy.

Key words:

nasopharyngeal carcinoma, long noncoding RNA TUG1, proliferation, invasion, mi? gration, apoptosis, radiosensitivity ,