Biological relevance of E-cadherin-catenin complex proteins in primary epithelial ovarian tumours

Abstract

This study analysed the biological relevance of E-cadherin, alpha-catenin, beta-catenin and gamma-catenin immunoexpression pattern (reduced vs. preserved phenotype) in epithelial ovarian tumours. Immunohistochemistry was used to evaluate the expression of these proteins in 154 epithelial ovarian tumours, consisting of 17 benign, 33 borderline and 104 malignant tumours. In borderline tumours, the immunoexpression pattern of E-cadherin (p = 0.014) and alpha-catenin (p = 0.030) associated with histological type. In malignant tumours, the immunoexpression pattern of E-cadherin was related with histological type (p = 0.001). The immunoexpression pattern of beta-catenin associated with histological type and tumour differentiation (p = 0.005, p = 0.025, respectively). The preserved phenotype of E-cadherin was most frequently observed in mucinous tumours, whereas reduced E-cadherin was most frequently observed in serous tumours. The preserved phenotype of beta-catenin associated with endometrioid carcinomas, while reduced beta-catenin associated with poorly differentiated serous and clear cell carcinomas. Although the reduced phenotype was the most frequent immunoexpression observed for all proteins of the E-cadherin-catenin complex in epithelial ovarian tumours, only beta-catenin showed a significant difference between benign, borderline and malignant tumours (p = 0.045), since borderline and malignant tumours most frequently showed the reduced phenotype. The immunohistochemical profile of beta-catenin was shown to be of biological relevance: reduced beta-catenin was correlated with loss of tumour differentiation and serous carcinomas that are known to depict aggressive biological behaviour in epithelial ovarian tumours.