Abstract: [Abstract] Objective  To investigate the expressions of the epithelial cell adhesion molecule (EpCAM) and E-cadherin and their clinical significance in urothelial carcinoma of bladder. Methods  The expressions of EpCAM and E-cadherin were analyzed by immunohistochemistry using a monoclonal antibody EpCAM and E-cadherin in 80 cases of normal mucosa and 156 cases of urothelial carcinoma of bladder. The expression levels of EpCAM and E-cadherin were analyzed in different clinical pathological factors. Moreover, EpCAM expression was investigated by comparison with E-cadherin. Results    The positive rate of EpCAM expression in bladder urothelial carcinoma was 53.2%, which was significantly higher than that in para-cancerous mucosa (13.8%，P＜0.01). The positive rate of EpCAM expression was significantly lower in bladder urothelial carcinoma than that in para-cancerous mucosa (35.9% vs 56.3%，P＜0.01). The positive expression of EpCAM was detected in high-grade urothelial carcinoma. The positive expression of E-cadherin was detected in low-grade urothelial
carcinoma. The expression levels of EpCAM increased with the increased clinical stages, pathological grades, tumor quantity,distant metastasis and tumor recurrence (all P< 0.05). The expression levels of E-cadherin decreased with the increased clinical stages, pathological grades, tumor quantity and distant metastasis (all P< 0.05). There was a negative correlation between expressions of EpCAM and E-cadherin in bladder urothelial carcinoma (r =-0.607, P < 0.01). Conclusion    The expressions of EpCAM and E-cadherin are associated with tumor malignancies, such as invasion and metastasis. The evaluation of the two markers has a certain value for determining tumor invasion and metastasis.

Key words: urinary bladder neoplasms, carcinoma, cadherins, cell adhesion molecules, immunohistochemistry, EpCAM