p53 tumor suppressor protein and tissue proliferative fraction in infiltrating duct carcinoma

Abstract

Background and Objectives Breast cancer continues to frustrate oncologists worldwide. In India, it is the second most common neoplasm among women and is increasing in incidence. Several molecular markers have been associated with a poor prognosis in patients with breast cancer, and the presence of these markers is often thought to provide information on the biological behavior of the malignant breast tumor. Much attention has recently been focused on the tumor suppressor gene p53. Mutation or alteration in this gene leads to the loss of negative growth regulation and hence to rapid cell proliferation. The present study was designed to evaluate the connection between expression of the p53 protein and its relation to the tissue proliferative compartment as measured by expression of the proliferating cell nuclear antigen (PCNA). Methods Expression of p53 and PCNA were detected by immunocytochemistry in paraffin-embedded sections of infiltrating duct carcinoma and control breast tissue (normal tissue and adenoma). Results A significant correlation was observed between expression of p53 and PCNA. A significant correlation was also observed between expression of p53 and grade of tumor and stage of disease. Conclusions Our results support the hypothesis that accumulation of p53 is associated with a high tumor proliferation rate an association that might be expected in view of the role of wild p53 as a negative regulator of cell proliferation.