The long non-coding RNA (lncRNA) urothelial carcinoma associated 1 (UCA1) is an oncogenic lncRNA in bladder cancer, and its upregulation is associated with enhanced cell invasion. However, the underlying mechanism remains to be elucidated. The present study demonstrated that UCA1 was positively associated with cell invasion ability and promoted epithelial-mesenchymal transition (EMT) of bladder cancer cells by inducing high mobility group box 1 (HMGB1). Furthermore, bioinformatics and luciferase reporter assays demonstrated binding sites of the tumor suppressive miR-143 within UCA1 and the 3'untranslated region of HMGB1. UCA1 negatively regulated miR-143 expression in a dose-dependent manner in bladder cancer cells. In addition, UCA1 and HMGB1 were upregulated and miR-143 was downregulated in bladder cancer specimens. Overall, the data suggested that UCA1 may promote the invasion and EMT of bladder cancer cells by regulating the miR-143/HMGB1 pathway, which exhibits an important regulatory role in the pathology of bladder cancer.
Keywords: bladder cancer; epithelial-mesenchymal transition; high mobility group box 1; miR-143; urothelial carcinoma associated 1.