The significance of E-cadherin in transitional-cell carcinoma of the human urinary bladder.

E-cadherin is a Ca(2+)-dependent intracellular adhesion molecule in the epithelial tissue. The urothelium also expresses E-cadherin molecules. We determined E-cadherin expression in bladder carcinoma immunohistochemically and investigated its relationship with pathological and clinical data. The percentage of cases showing pattern B, less than 50% of which cancer cells expressed the same intensity of E-cadherin as did the normal epithelium, was higher in cases of high-grade or high-stage tumors as compared with those of low grade or low stage. Heterogeneous staining was observed in the same specimens, which suggested changes in the cell phenotype. Immunoblotting demonstrated no evidence of gross alteration of E-cadherin molecules. The decrease in E-cadherin expression was associated with the invasiveness of bladder carcinoma, as has been reported in other carcinomas.