Abstract
Expression of the c-erbB-2 oncoprotein (ErbB-2) and the p53 gene product was examined in the operative specimen from 68 human breast cancer patients. These patients were detected immunohistochemically by the streptavidin-biotin method using a commercial kit (SABPO kit, Nichirei Co., Inc., Tokyo) and monoclonal anti-mouse antibodies specific for the intracellular domain of the protein. Expression was evaluated as positive when specific membranous staining for c-erbB-2, and nuclear staining for p53, were observed in a majority of cancer cell nets. The expression of the estrogen receptor (ER) as a marker of hormone dependency was also examined ; serum levels of these two gene products were measured (c-erbB-2: mAbl Triton Diagnostics Co., Inc. Alameda, CA) (p53: Ab-2 Oncogene Science Co., Inc., Uniondale, NY) . Tissue c-erbB-2 and p53 products were positive in 22.1% (15/68), and 25.0% (17/68) of the components, and serum c-erbB-2 and p53 protein levels were positive in 19.1% (13/68) and 7.4% (5/68) . Oncoprotein (c-erbB-2 or p53) tissue expression-positive patients showed a tendency to be estrogen receptor negative and 8 cases were positive on p53 protein expression out of 25 scirrhous breast cancer. The data might provide a better characterization of the human breast cancer phenotype, and two expressions of the c-erbB-2 and p53 protein in the tissue would be useful for judgements of prognosis.
