The expression of E-cadherin-catenin complex in adenoid cystic carcinoma of salivary glands.

The aim of this study was to investigate the expression of the E-cadherin-catenin (E-cad-cat) complex in human salivary adenoid cystic carcinoma (ACC) and determine the effects of E-cad-cat expression on tumor differentiation, metastasis, and invasion, as well as its clinical significance. The expression of adhesion molecules, which included E-cadherin, alpha-catenin, and beta-catenin, on 10 cases of normal salivary glands, and 50 cases of human salivary ACC were investigated by immunohistochemistry. Strong and stable expression of E-cad-cat complex showed in normal salivary glands tissues. However, weaker expression and even complete absence, of the positive signals were shown on all ACC cases. Coexpression of E-cad-cat were detected in 29 (58%) of the 50 ACC specimens. Positive staining of E-cad-cat complex were detected in 7 (39%) of the 18 ACC primary sites that had aggressive phenotype of nerve and vasculature. Strong positive signals of E-cad-cat complex are shown in normal salivary glands, and the down-regulated expression were observed in ACC cases. The expression of E-cad-cat complex is associated with a more aggressive phenotype on nerve and vasculature. No association with various histopathologic subtypes was found. However, absent or low E-cad expression was observed more frequently in solid carcinomas than in cribriform or tubular carcinomas. Down-regulation of E-cad-cat complex may be associated with canceration of normal salivary glands. The expression levels of E-cad-cat were positively correlated to the differentiation of ACC tumor cells.