Survivin

Survivin, a novel member of inhibitor of apoptosis(IAP) protein family, suggested in both control of apoptosis and cell division. The initial mechanistic studies found that survivin is cell cycle-regulated with a robust expression in G2/M phase.

The localization of survivin which is associated with microtubules, centrosomes and mitotic spindles appears to be required for its function in regulation of apoptosis. Survivin is not expressed in normal adult tissue expect for the thymus and placenta, but it is abundant in fetal tissue and various human tumors, including colon, lung, gastric, breast and bladder cancer. Several proteins associated with malignant transformation of cells can induce auto-antibodies which are detectable in serum. Overexpression of survivin by cancer cells may lead to anti-survivin antibody responses and cytotoxic T-lymphocyte responses against the cancer. Measuring anti-survivin auto-antibodies in human sera and evaluate the possibility of suffering from cancer. We will develop the ELISA kit for anti-survivin antibody detection, this kit with a low false positive rate is a good test for cancer screening.

HeLa cells were transfected with GFP-Survivin, simultaneously fixed and extracted, and analyzed for GFP labeling by confocal fluorescence microscopy. DNA was stained in red. GFP-Survivin localizes to kinetochores of metaphase chromosomes and decorates the entire length of mitotic spindle microtubules at metaphase. For details, see the article by Giodini et al. Regulation of Microtubule Stability and Mitotic Progression by Survivin, Cancer Research 2002; 62: 2462-2467.(GO)

Besides of the survivin auto-antibody detection, the survivin antigen detection could be applied as the specific tumor maker in specific sample. Such as detection of survivin in the urine sample assists in diagnosis of bladder cancer. Bladder cancer is a more common cancer now. At present, the best way to accurately diagnose bladder cancer remains performing cystoscopy and/or biopsy. It was demonstrated that survivin expression in bladder cancer (transitional-cell carcinoma, TCC) is an attractive prognostic marker for bladder cancer. Using survivin from urine as the basis of a potential bladder cancer screening test makes sense to us early on. All patients with bladder cancer had detectable survivin in their urine, while none of the healthy volunteers did. Highly sensitive and specific determination of urine survivin appears to provide a simple, noninvasive diagnostic test to identify patients with new or recurrent bladder cancer.

Dohi T et al. Mitochondrial survivin inhibits apoptosis and promotes tumorigenesis, J.Clin.Invest 2004; 114: 1117-1127 (GO)