The results of this study suggest that c-erbB-2 protein overexpression, a marker of poor prognosis in breast cancer, is associated with a lack of response to endocrine therapy on relapse, and particularly in combination with EGFR may be useful in directing therapeutic choices.
This study suggests that overexpression of the c-erbB-2 oncoprotein appears to be an important indicator of relapse in stage I-II breast cancer when singly evaluated.
This high incidence of HER2 gene amplification with accompanying overexpression in non-invasive breast tumors suggests that perturbations of the HER2 oncogene are among the earliest and most common genetic lesions in human breast cancer.
Thus, the oncogene ERBB-2 is often amplified in human tumors, but breast cancer is characterized by an especially high frequency of ERBB-2 amplification.
The relative ERBB2 copy number determined by FISH in 10 breast cancer cell lines correlated strongly with Southern blot results (r = 0.98) when probes for an identical reference locus were used in the two methods.
Overexpression of the p53 and c-erbB-2 proteins indicates a high malignant potential in ANN breast cancer, but it is not a significant prognostic factor independent of the cell proliferation rate.
Amplification of HER-2/neu, a protooncogene related to the epidermal growth factor receptor, has prognostic significance in patients with breast cancer.
Ninety-seven unselected breast carcinomas were immunostained for estrogen and progesterone receptors, Ki-67 proliferation-associated antigen, p53 tumor suppressor gene product (p53), and c-erbB-2 protein.
In addition, the level of c-erbB-2-protein was investigated by immunohistochemistry in 271 breast carcinomas which were operated in the years 1984-1987.