Expression of Survivin in colorectal cancer and its clinical significance

OBJECTIVE: To study the expression of inhibitor apoptosis protein of Survivin in colorectal carcinoma and its correlation with clinicopathological feature and prognosis.METHODS:Immunohistochemical staining of Survivin was performed by the standard streptavidin-peroxidase (SP) technique for the paraffin sections of 106 colorectal cancers.The relationship between the Survivin expression and the clinicopathological parameters was analyzed. Kaplan-Meier method was used to investigate the correlation between Survivin expression and survival rate of the patients for whom long term follow up data were available. RESULTS:The positive rate of Survivin in colorectal carcinoma was 64.2%(68/106),no expression of Survivin was detected in normal colorectal tissues. Significant relationship was found between Survivin expression and the histological differentiation grade of colorectal carcinoma. The positive rate of Survivin in middle to well differentiated colorectal carcinoma(72.4%,63/87)was significantly higher than that in poorly differentiated colorectal carcinoma(26.3%,5/19),P0.05. However, there was no correlation between Survivin expression and other clinicopathological parameters such as sex, tumor site, tumor depth, lymph node metastasis, distant metastasis, and Dukes' stage.The 5-year survival rate of patients with Survivin-positive tumors was significantly lower than that of patients with Survivin-negative tumors (42.6% vs 68.4%, P0.05, log-rank test).CONCLUSIONS: A high expression of inhibitor apoptosis protein of Survivin is found in colorectal carcinoma.The expression of Survivin is correlated with prognosis. It may be a significant prognostic parameter of worse outcome in colorectal carcinoma.