To further investigate whether TUG1 knockdown enhanced radiosensitivity of bladder cancer cells via inhibiting HMGB1, SW780 and BIU87 cells transfected with si-TUG1 or combination of si-TUG1 and pcDNA-HMGB1 were treated with 2 Gy radiation. This evidence concerns the gene TUG1 and urinary bladder cancer.