Evaluating the expression of survivin gene as a specific tumor marker for prognosis of bladder cancer

Inhibition of apoptosis may favor the onset and progression of cancer. Survivin is an inhibitor of apoptosis that has been considered as a potential marker for diagnostic and/or prognostic of bladder cancer. The survivin protein regulates both cell division and cell death and is overexpressed in the vast majority of human cancers. In this study, the expression pattern and potential prognostic value of survivin was assessed in Formalin-Fixed Paraffin-Embedded (FFPE) samples of bladder tumor. FFPE samples, from patients with a well-known five-year survival record, were assessed by semi-quantitative RT-PCR technique. 51 samples from 30 patients were analyzed on the basis of Survivin expression. Tissue distribution and subcellular localization of survivin protein in tumor tissues was also examined by immunohistochemistry (IHC). The expression of survivin was detected in 66.6% of the samples, with an increase of expression in higher grades of tumor. Furthermore, survivin was overexpressed in 2nd and 3rd recurrences of the same patients. Also, with the increased malignancy and accordingly increased expression of surviving, the overall 5-year survival rate of patients was significantly declined (P=0.036). IHC results also localized a nuclear localization for Survivin protein in tumor tissues. In conclusion, we were able to detect the expression of survivin in FFPE samples of bladder tissues, at the level of mRNA and protein and find a correlation between the level of Survivin expression and the degree of malignancy of the tumors. Our findings introduce Survivin as a suitable prognostic marker for predicting the bladder tumors.