Detection of survivin expression in bladder cancer and renal cell carcinoma using specific monoclonal antibodies.

Survivin, which is highly expressed in the majority of tumors, but not in most normal adult tissues, has been identified to have significant clinical applications. In the present study, using survivin­specific monoclonal antibodies (mAbs), we aimed to establish methods for detecting the expression of survivin in cancer cell lines, serum samples, urine samples and cancer tissues from patients with bladder cancer (BCa) and renal cell carcinoma (RCC), and to evaluate the efficacy of survivin as a tumor marker in the surveillance of BCa and RCC. First, mAbs were labeled with horseradish peroxidase (HRP), and a sandwich enzyme­linked immunosorbent assay (ELISA) with mAbs and HRP­conjugated mAbs was developed to detect survivin expression in serum and urine samples from BCa and RCC patients, with samples from healthy controls (HCs) used for comparison. The HRP­conjugated mAbs were also used to detect survivin expression in cancer cell lines by western blotting. Survivin expression in cancer tissues from BCa patients was also evaluated by immunohistochemistry. The results showed that the sandwich ELISA was successfully established, and significantly higher expression of survivin was subsequently detected in BCa and RCC patients as compared with HCs in both urinary and serum samples (P<0.05), and was more pronounced in urine. The HRP­mAbs could recognize survivin in cancer cell lines. Western blotting and immunohistochemistry results confirmed survivin expression in the 5637 BCa cell line, as well as BCa tissues. In addition, the expressions of survivin in BCa tissues, urine and serum were consistent in our study. In conclusion, the sandwich ELISA successfully established in the present study was of high sensitivity and specificity in the detection of survivin expression. The results also indicated that survivin is a potential tumor marker for the surveillance of BCa and RCC.