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.
Our study examines the HER-2/neu oncogene in 61 primary human breast cancers at both the DNA level (by Southern blotting) and the protein level (by immunohistochemical methods).
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.
In contrast, only a trend towards higher relapse was observed in erbB-2 amplified breast cancers with respect to later events (occurring over the first 30-month period).
p53 and c-erbB-2 protein expression in breast carcinomas. An immunohistochemical study including correlations with receptor status, proliferation markers, and clinical stage in human breast cancer.
Thus the strong expression of c-erbB-2 oncogene in primary breast cancers appears to be an additional and particular prognostic factor in lymph node positive patients.