NF-κB-Activated lncRNACASC9 Promotes Bladder Cancer Progression by Regulating the TK1 Expression

Long noncoding RNAs (lncRNA) are involved in cancer development, but the roles of most lncRNAs are undocumented. In this study, we identified lncRNAs that were abnormally expressed in bladder cancer. We found that lncRNACASC9 plays an important role in the progression of bladder cancer. CASC9 was highly expressed in bladder cancer cells and tissues, and the prognosis of bladder cancer patients with high expression of CASC9 was poor. The results of colony formation assays, CCK-8 assays, EdU assays, transwell assays, mouse xenograft models, and tail vein injection lung metastasis model showed that CASC9 could promote bladder cancer cells growth and metastasis both in vitro and in vivo. Mechanistically, through FISH experiments, luciferase reporter experiments, and RIP experiments, we proved that CASC9 regulated the expression of TK1 by adsorbing miR-195-5p, thereby exerting an oncogenic effect in bladder cancer. Taken together, our findings support that the CASC9/miR-195-5p/TK1 axis is a critical pathway in the tumorigenesis and progression of bladder cancer, implicating a new therapeutic direction for the treatment of bladder cancer.