BACKGROUND: The aim of this study was to investigate the expression of long non-coding RNAs (lncRNA) cancer susceptibility candidate 2a (CASC2a) in patients with urothelial carcinoma of the bladder (UCB) and its predictive value in the recurrence of UCB after radical cystectomy (RC).
MATERIAL AND METHODS: Tumor and paired adjacent normal tissues were obtained from 112 patients with UCB who underwent RC in our hospital from March 2010 to March 2012. The expression of CASC2a was evaluated by quantitative reverse transcriptase polymerase chain reaction (qRT-PCR) and fluorescence in situ hybridization (FISH).
RESULTS: CASC2a was down-regulated in UCB tissues, and was highly negatively correlated with the pT, pN, tumor size, and lymphovascular invasion (LVI). The sensitivities of CASC2a for diagnosing UCB and its recurrence after RC were 89.30% and 81.55%, respectively, and the specificities were 71.43% and 58.21%, respectively. Patients with a high expression of CASC2a had a higher 5-year recurrence-free survival rate than those with low expression of CASC2a. Kaplan-Meier survival analysis demonstrated that the pT, pN, tumor grade, tumor size, concomitant carcinoma in situ (CIS), LVI, soft tissue surgical margin (STSM), and CASC2a expression were related to the recurrence in patients undergoing RC for UCB. Cox proportional hazard model analysis showed that CASC2 expression, pT4, lymph node metastasis, and CIS were independent risk factors.
CONCLUSIONS: CASC2a was down-regulated in patients with UCB, and was associated with the risk of recurrence among patients undergoing RC, indicating that lncRNAs could act as predictive biomarkers and potential therapeutic targets in bladder cancer, including CASC2a.

Keywords: Early Diagnosis, Neoplasm Recurrence, Local, RNA, Long Noncoding, Urinary Bladder Neoplasms