Non-muscle myosin II is an independent predictor of overall survival for cystectomy candidates with early-stage bladder cancer.

Non-muscle myosin heavy chain IIA (NMHC IIA) plays a significant role in tumor progression and metastasis. The aim of this study was to explore the relationship between the expression levels of NMHC IIA and the characteristics, prognosis of patients who were cystectomy candidates with early-stage bladder cancer. Real-time PCR was used to examine the expression of NMHC IIA mRNA in 16 paired bladder cancer and the adjacent normal tissues. The expression of NMHC IIA protein in 167 specimens of bladder cancer was determined by immunohistochemistry assay. Statistical analyses were performed to evaluate the association between the expression of NMHC IIA, and clinicopathological features and prognosis. Compared with adjacent normal bladder tissues, upregulated expression of NMHC IIA mRNA was observed in 81.3% of bladder cancer tissues (P=0.011). Moreover, the higher levels of NMHC IIA expression were positively correlated with the histopathological classification (P=0.021), lymph node metastasis (P=0.047) and cancer-related mortality (P=0.030). The 5-year survival rate of patients with higher NMHC IIA expression was significantly lower than that of patients with lower NMHC IIA expression (P=0.004). Furthermore, in multivariate analysis by Cox regression model, high NMHC IIA expression was confirmed to be an independent molecular marker (P=0.047), while grade (P=0.020) and clinical T stage (P=0.049) were also significant prognostic factors. Expression of NMHC IIA mRNA was higher in bladder cancer compared to the adjacent normal tissues. The detection of NMHC IIA protein expression is potentially useful in prognostic evaluation of cystectomy candidates with early-stage bladder cancer.