The expression of E-cadherin and catenins in sporadic colorectal carcinoma

The E-cadherin/catenin complex plays a major role in epithelial cell-cell adhesion. Immunohistochemical studies have highlighted perturbation in the expression and distribution of E-cadherin and catenins in sporadic colorectal neoplasms. In this study, we compared the expression of E-cadherin and catenins (alpha-, beta-, and gamma-catenin) in 30 sporadic colorectal carcinomas with that in the adjacent nonneoplastic mucosa and assessed whether any perturbation in the level of expression occurred at the messenger RNA (mRNA) or protein level. We also compared the expression of E-cadherin and catenins in 13 lymph node deposits and the primary tumors. Immunohistochemistry was used to study the level of expression and cellular distribution of E-cadherin and catenins. Levels of mRNA were studied by in situ hybridization. E-cadherin and catenin immunoreactivity was increased with cytoplasmic accumulation in more than 85% of the neoplasms. There were marked increases in the levels of mRNA in the carcinomas compared with the nonneoplastic mucosa. Nuclear localization of beta-catenin was higher at the invasive margin of some tumors, but expression of E-cadherin and catenin transcripts in the lymph node deposits showed no consistent relationship to that in the primary tumors.