Reduced expression of MTUS1 mRNA is correlated with poor prognosis in bladder cancer.

Mitochondrial tumor suppressor 1 (MTUS1) is a newly identified candidate tumor suppressor gene. Previous studies have demonstrated that the expression status of MTUS1 is altered in several types of tumors. However, its clinical significance for bladder cancer patients remains undetermined. In this study, we detected the expression of MTUS1 mRNA in bladder tumors and paired normal samples obtained from 5 patients using semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR). A significant downregulation of MTUS1 mRNA expression was observed in the tumor tissues compared with the corresponding normal bladder tissue (P<0.001). We further tested the expression of MTUS1 mRNA in 55 bladder cancer tissues and 10 adjacent normal bladder tissues by quantitative real-time RT-PCR. Correlations between MTUS1 and clinicopathological features and prognosis were investigated by statistical analyses. The results showed that MTUS1 expression was correlated with tumor grade, stage, size and number (P<0.001, P<0.001, P=0.034 and P=0.029, respectively). Patients with low levels of MTUS1 mRNA expression had a poor prognosis compared with those with a high expression (P<0.001). Univariate and multivariate logistic regression prognostic analyses revealed that MTUS1 mRNA was an independent prognostic factor for disease-free survival in bladder cancer (P<0.05). In conclusion, these data suggest that MTUS1 is significant in the progression of bladder cancer and that the status of MTUS1 mRNA expression is a novel prognostic marker for predicting bladder tumor disease-free survival.