Expression of Anaphase Promoting Complex (APC) and APC Regulatory Proteins in Invasive Ductal Carcinoma Associated with Paget's Disease

ABSTRACT

BACKGROUND: Oncogene expression in Paget's disease of the breast is not well known. To characterize invasive ductal carcinoma associated with Paget's disease, we studied expression of anaphase promoting complex (APC) with its regulatory proteins. METHODS: Immunohistochemical stainings were done with 10 cases of invasive ductal carcinoma associated with Paget's disease for APC, pituitary tumor transforming gene (PTTG), cyclin B1, p53, cyclin D1, and c-erbB-2. The expressions of these markers in Paget's disease were compared with those in the associated with carcinoma. RESULTS: APC, PTTG, cyclin B1, and c-erbB-2 were positive in all of the cases with both Paget's disease and underlying carcinoma. p53 was expressed in Paget's disease of 6 cases (60%) and in carcinoma of 7 cases (70%). Cyclin D1 was positive in Paget's disease of 8 cases (80%) and in carcinoma of 9 cases (90%). CONCLUSIONS: Breast carcinomas with Paget's disease seem to be distinguished by the high expression of APC, cyclin B1, PTTG, c-erbB2, and cyclin D1 in contrast to breast cancers without Paget's disease. Furthermore, the similar expression patterns of APC and APC regulatory proteins in both Paget's disease and underlying breast cancer support the epidermotropic theory as its pathogenetic mechanism.