E-cadherin÷CD44 immunophenotype in the epithelial-mesenchymal transition of bladder urothelial carcinomas

The alteration of epithelial stability, which includes changes in the expression of E-cadherin and CD44, is one of the complex biomolecular mechanisms involved in the tumoral epithelial-mesenchymal transition (EMT) process. We followed the E-cadherin÷CD44 immunophenotype by single and double detections in 25 cases of bladder urothelial carcinomas. Our study investigated simultaneously the differences in expression of the two markers, in different tumoral compartments, according to the prognostic parameters of the lesions. The study indicated significant differences in the expression of E-cadherin in relation to tumor grade, depth of invasion, tumor stage and Ki-67 proliferation index (PI), both intratumoral and at the advancing edge. For CD44, expression differences were found between the tumor grades in intratumoral sites, while for both intratumoral and advancing edge compartments the differences occurred for the depth of tumor invasion, tumor stage and Ki-67 PI. The only differences in the expression of the two markers in relation with the presence of lymph node metastasis were for E-cadherin at the advancing edge. In this study, the intratumoral E-caderin-÷CD44- immunophenotype, respectively E-caderin-÷CD44+ at the advancing edge were associated with the tumor aggressiveness analyzed parameters. The maintenance of CD44 expression at the advancing edge represents a negative prognostic factor for bladder urothelial carcinoma and supports the implication of EMT process, through the existence at this level of a cell population with particular properties.