ASSAY OF THE C-ERBB-2 ONCOGENE ENCODED PROTEIN BY ELISA AND IMMUNOCYTOCHEMISTRY IN HUMAN BREAST-CANCER

The c-erbB-2 gene is amplified in a wide variety of different adenocar cinomas. Generally, gene amplification correlates with increased expre ssion of the c-erbB-2 oncoprotein. Previous assays for the c-erbB-2 on coprotein have been qualitative or semi-quantitative. In this investig ation using human breast cancers, c-erbB-2 oncoprotein levels as measu red by enzyme-linked immunosorbent assay (ELISA) correlated significan tly with semi-quantitation by immunocytochemistry (r = 0.843, P < 0.00 01, n = 97). The cut-off point for the ELISA which gave the strongest agreement with immunocytochemistry was 15 units/mu g protein. It is co ncluded that detection of c-erbB-2 oncoprotein by ELISA is quantitativ e and objective.