To know the biological function of the adherens junction associated with histological dedifferentiation, intramuscular invasion, and clinical staging, we studied the expressions of E-cadherin and alpha- and beta-catenin mRNAs in endometrial cancers in comparison with those in normal uterine counterparts. As dedifferentiation, myometrial invasion and staging advanced, the expressions of E-cadherin and beta-catenin mRNAs decreased. This suggests that the function of adhesive molecules in the adherens junction might be disturbed, leading to invasiveness and metastatic potential.