Abstract: Objective: To investigate the expression of Smac/DIABLO in epithelial ovarian carcinomas and its clinical significance. Methods: The expression of Smac/DIABLO proteins was detected with immunohistochemistry. Results: The positive expression rate of Smac/DIABLO in ovarian carcinomas was significantly lower than that in benign ovarian tumors and normal ovaries（χ²=14.06, P <0.008 3; χ²=19.15, P <0.008 3）. In ovarian carcinomas, the expression of Smac/DIABLO was significantly decreased during progression from early to advanced tumour clinical stages and histological grade（F=7.23, P <0.05; F=4.48, P <0.05）. There was relationship between the low expression of Smac/DIABLO and poor prognosis of epithelial ovarian carcinomas. Conclusions: There was low expression of Smac/DIABLO in epithelial ovarian carcinomas, Smac/DIABLO was related to the poor prognosis of ovarian carcinomas.

Key words: Epithelial ovarian carcinomas, Smac/DIABLO, Apoptosis, Immunohistochemistry