Immunohistochemical expression and serum level of survivin protein in colorectal cancer patients

Survivin is one of the apoptosis-related inhibitors that is associated with a more aggressive behavior and a poor prognosis in numerous types of malignancies, including colorectal cancer (CRC). The objective of the present study was to perform immunohistochemical tissue analysis of survivin expression and serum analysis of survivin levels in CRC patients. The study group consisted of 55 CRC patients. Survivin expression was assessed by immunohistochemistry in 38 patients using monoclonal antibodies. Color reactions were observed in the nucleus and cytoplasm of the cancer cells. The expression was defined based on the H-score method. The level of survivin was determined using the enzyme-linked immunosorbent assay method. A positive immunoreaction was observed in the tumor tissues of 84.2% (32/38) of patients with CRC, consisting of nuclear (63.2%; 24/38) and cytoplasmic (81.6%; 31/38) expression. The survivin nuclear expression was associated with tumor mass location and the presence of distant metastases (P=0.048 and P=0.026, respectively). Survivin was detected in the sera of 38.2% (21/55) of CRC patients and in 81.8% (18/22) of healthy individuals. Serum protein levels were found to correlate with hematocrit (P=0.035), hemoglobin (P=0.008) and albumin (P=0.045), but not with any of the investigated clinicopathological parameters. The immunohistochemical positive reaction of survivin in the nuclei of cancer cells may condition their proliferative capacity, which is associated with higher risk of developing metastatic foci. Thus, the present study suggests that the expression of survivin may have diagnostic implications in cancer of the colon and thus requires further research. By contrast, the survivin serum level in CRC patients appears to be diagnostically ineffectual for clinical use.