Heat shock protein expression independently predicts survival outcome in schistosomiasis-associated urinary bladder cancer.

BACKGROUND Heat shock proteins (HSPs) are synthesized by cells in response to various stress conditions, including carcinogenesis. These molecules have been studied in several malignancies, among which bladder carcinoma. This is the first study attempting to clarify the significance of HSP27 and HSP70 in schistosomiasis-associated bladder carcinoma and their relation to prognosis. METHODS HSP27 and HSP70 were localized immunohistochemically in tissue sections from 75 chistosomiasis-associated bladder carcinomas. Their expression was correlated with clinical and pathological features and their impact on 5-year disease-free survival was studied with univariate and multivariate analysis. RESULTS In all, 45 and 51 patients were positive for HSP27 and HSP70 expression, respectively. A significant correlation was found between expression of both HSPs and tumor grade, stage, DNA ploidy and recurrence. In univariate analysis, a statistically significant association of HSP27 and HSP70 expression with 5-year disease-free survival was found. In a multivariate Cox proportional hazards model, both HSP27 and HSP70 maintained a statistically significant impact on survival. CONCLUSIONS The current results indicate that expression of HSP27 and HSP70 may have prognostic relevance in patients with schistosomiasis-associated bladder cancer. HSPs may be useful markers for patients with this type of bladder carcinoma and may be used for predicting disease progression.