The expression of cadherin-catenin complex in association with the clinicopathologic features of early gastric cancer.

Although impaired expression of E-cadherin (E-cad) is frequently observed in tumors with aggressive histopathologic characteristics, the correlation between alpha-catenin (alpha-cat) expression and the clinicopathologic features of early gastric cancer have not been fully examined. In this study, we evaluated the expression of E-cad and alpha-cat by early gastric carcinomas, and examined the relationships between this expression and various clinicopathologic characteristics. A total of 69 specimens obtained from surgery were studied by immunohistochemistry. Reduced expression of E-cad and alpha-cat were found in 53.6% and 65.2% of the tumors, respectively, and a significant correlation was observed between the decreased expression of E-cad or alpha-cat and tumor histology, the quantity of stroma, and the infiltration pattern of the tumor. The reduced expression of alpha-cat correlated more strongly with these features than E-cadherin expression. Furthermore, alpha-cat expression was also related to the lymph node metastasis of tumors. The expression of E-cad or alpha-cat in the primary tumor was consistent with the expression of tumor cells that invaded the lymphatic vessels, but discordant with staining in the metastasized lymph nodes. In some cases, as the tumor invaded deeper, the expression of E-cad or alpha-cat changed from preserved to reduced. Our observations suggest that the reduced expression of E-cad or alpha-cat may be involved in the initial steps leading to the invasion and metastasis of early gastric cancer.