Immunohistochemical patterns for alpha- and beta-catenin, E- and N-cadherin expression in ovarian epithelial tumors.

OBJECTIVES: This study aims were to analyze and compare the E- and N-cadherin, beta- and alpha-catenin expression in benign and malignant epithelial neoplasms of the ovary, correlating with tumor staging, histological grade, and presence of metastases during evolution. METHODS: Immunohistochemical reactions were performed on paraffin-embedded tissues and evaluated according to the number of positive, stained cellular structures and reaction intensity for each molecule. Information about histological type and grade, tumoral stage, and disease evolution was obtained from the patients' clinical records. RESULTS: Most of the carcinomas showed more intense beta-catenin reaction (P = 0.02). More than 50% of the endometrioid carcinomas showed increased beta-catenin expression, with a large number of positive cells and more intense staining, being the same also observed for most of the serous benign tumors (P < 0.01). E-cadherin membrane expression was frequently observed in carcinomas without metastasis, whereas cases with metastases in evolution were negative or showing E-cadherin expression only in the cytoplasm (P = 0.04). N-cadherin expression differed according to histological type and grade and alpha-catenin was also related to histological type, but these findings were not conclusive. CONCLUSIONS: Increased beta-catenin expression was more frequent in ovarian carcinomas, especially, but not only, in the endometrioid ones. The maintenance of E-cadherin expression in cellular membrane may be an independent marker of good prognosis in ovarian cancer. New studies about N-cadherin and alpha-catenin and their importance during ovarian carcinogenesis will be required.

Epithelial phenotype of cultured ovarian tumor cells

Epithelial differentiation is an early or predisposing step in epithelial ovarian carcinogeneses which occurs in pre-neoplastic lesions, benign tumors and normal ovarian surface epithelium (OSE) of women with a familial history of ovarian cancer. During neoplastic progression, OSE acquires a more epithelial aspect, including the expression of CA125 protein and other epithelial markers, whereas mesenchymal characteristics diminish. In this study, we investigated 26 primary cell cultures, including benign and malignant OSE neoplasms, obtained from women who underwent surgical removal of the ovaries at the university hospital of the State University of Campinas (Campinas, SP, Brazil). Cell morphology was assessed from the time of cell adhesion to the substrate up to the third of fourth passage. CA125 was detected byimmunohistochemistry at each passage. Serum CA125 levels were obtained from clinical records and heredograms were constructed using the information about the recurrence of familial cancer provided by the patients. Seventy-eight percent of the malignant OSE tumors analyzed showed an epithelial cell phenotype and 71 percent were positive for CA125. Benign and normal OSE cultures had a fibroblast-like cell phenotype, a negativa CA125 expression and an inexpressive history of recurrent familial cancer, compared to malignant OSE tumors. We concluded that the expression of an epithelial phenotype in vitro may serve as an important tumor marker in malignant OSE neoplasms. In certain cases, this marker may be more reliable than the determination of serum CA125 levels. However, the relationship between the expression if the epithelial phenotype in vitro and a familial predisposition to tumors development remains to be determined.