The Immunohistochemical Pattern of Epithelial-Mesenchymal Transition Markers In Endometrial Carcinoma

The majority of endometrial carcinoma are diagnosed at an early stage and exhibit a favorable prognosis. However, 10% to 15% of ECs recur and the majority are type II tumors which are high-grade carcinomas. The epithelial-mesenchymal transition (EMT) has been considered as a fundamental step for the development of the invasive phenotype of cancer cells. During EMT, many of epithelial surface markers, primarily E-cadherin disappear, and mesenchymal markers including N-cadherin gain. This feature resides predominantly at the invasive front (IF) of the tumor. Therefore, we examined the immunohistochemical expression of E-cadherin and N-cadherin at the IF, in central areas of the tumor and lymphovascular space, in type I and type II endometrial carcinoma. The association of each protein with the clinicopathologic features was also evaluated. Our results confirmed a stronger E-cadherin immunostaining in type I tumors indicating that the loss of E-cadherin may be responsible for a more aggressive behavior of type II ECs. In both types, E-cadherin was strongly expressed in central areas and the reactivity decreased toward the IF. On contrary, N-cadherin was overexpressed at the IF confirming an inverse relationship between these markers. In addition, a decrease in E- cadherin expression was observed in cells within the lymphovascular space. Downregulation of E-cadherin was associated only with high-grade tumors while no correlations between both markers and other clinicopathologic features were found. Our results confirm that EMT occurs at the IF that represents a critical interface between the tumor and the host