Decreased expression of CD44, alpha‐catenin, and deleted colon carcinoma and altered expression of beta‐catenin in ulcerative colitis‐associated dysplasia and carcinoma, as compared with sporadic colon neoplasms

BACKGROUND: To clarify the cell adhesion status in ulcerative colitis (UC)-associated colon neoplasm, expression of cell adhesion molecules were investigated and compared with that of sporadic colon neoplasm. METHODS: A total of 14 low grade dysplasias, 16 high grade dysplasias, and 8 adenocarcinomas associated with UC and 17 sporadic adenomas with mild to moderate dysplasia, 22 adenomas with severe dysplasia, and 15 invasive adenocarcinomas were immunohistochemically examined using monoclonal antibodies against CD44, E-cadherin, alpha- and beta-catenin, and deleted colon carcinoma (DCC). RESULTS: CD44, especially its standard form, and DCC expression was stronger in the sporadic colon neoplasms than in the UC-associated lesions. Although E-cadherin did not show significant differences between the two cases, alpha-catenin was more expressed in sporadic colon adenomas with severe dysplasia and carcinomas than in their UC-associated counterparts. Membranous beta-catenin staining was stronger in UC-associated neoplasms, whereas sporadic lesions had greater cytoplasmic and nuclear expression. CONCLUSIONS: The differences in cell adhesion molecule expression suggests that UC-associated and sporadic colon neoplasms arise from different pathways of tumorigenesis.