Epithelial-mesenchymal transition markers in malignant ovarian germ cell tumors

The purpose of this study was to determine the expression and potential clinical role of epithelial-to-mesenchymal transition (EMT)-related factors in malignant ovarian germ cell tumors (MOGCT). Protein expression of E-cadherin, N-cadherin, P-cadherin, Zeb1, HMGA2, and vimentin by immunohistochemistry was analyzed in 42 MOGCT from patients treated in Norway during the period 1981-2001. Expression was analyzed for association with clinicopathologic parameters. E-cadherin (p = 0.016) and HMGA2 (p = 0.002) expression was significantly higher in immature teratomas and yolk sac tumors compared with dysgerminomas. Vimentin (p < 0.001) and Zeb1 (p = 0.029) staining was significantly higher in immature teratomas compared with yolk sac tumors and dysgerminomas, whereas no significant differences were observed for N-cadherin and P-cadherin. EMT-associated markers were not significantly related to clinicopathologic parameters including age, tumor diameter, and FIGO stage. In conclusion, based on this limited series, EMT-associated markers are not associated with clinical parameters in MOGCT, in contrast to ovarian carcinoma. EMT-related proteins are differentially expressed among various MOGCT subtypes, suggesting differences in biological characteristics associated with invasion and metastasis.