Specific expression of the pS2 gene in subclasses of breast cancers in comparison with expression of the estrogen and progesterone receptors and the oncogene ERBB2.
Neu-protein overexpression in breast cancer. Association with comedo-type ductal carcinoma in situ and limited prognostic value in stage II breast cancer.
This is the first study showing that a determination of the level of c-erbB-2 protein in paraffin-embedded tumor sections may have prognostic value for the course of human breast cancer.
Therefore, immuno-histological diagnosis with anti-c-erbB-2 antibody might be useful as an indicator to predict lymph-node involvement in breast cancer.
Five proto-oncogenes were found to be occasionally amplified in primary breast cancers: c-ERBB-2 (11%), c-MYB (3%), c-RAS-Ki (3%), INT-2 (4%) and c-MYC (6%).
Membrane protein levels of erbB-2 and epidermal growth factor (EGF) receptor as well as gene aberrations affecting these proto-oncogenes in human mammary cancer were determined in primary and metastatic lesions.
Correlation of erbB-2 gene amplification with low levels of estrogen and/or progesterone receptors in primary breast cancer: do erbB-2 products delineate hormone-independent tumors?
The c-myc gene was amplified 5-7-fold in two adenocarcinomas, the H-ras gene 3 5-fold in one adenocarcinoma, while the K-ras and the neu gene were amplified in lung metastases from a colorectal and a breast cancer primary respectively.
These findings confirm and extend earlier results of studies of int-2, c-erbB-2 and c-myc amplification in human breast cancers and point to a role for int-2 activation in certain cases of recurrent breast malignant neoplasia.
Some of these mutations involve amplification of protooncogenes (c-myc, c-erbB-2, and int-2) that have been shown to contribute to experimentally induced breast cancer in mouse model systems.
About 40% of breast carcinomas contain either amplified c-myc or c-erbB-2 protooncogenes, whereas simultaneous amplification of both was seen in only one sample, suggesting the involvement of two distinct molecular mechanisms in breast cancer.
Amplification and over-expression of the c-erbB-2 proto-oncogene were observed in 27% and 47% of tumors, respectively, and were strongly associated with breast cancers of the most unfavorable prognosis, namely IBC and NBC with multiple positive axillary nodes.
Since overexpression of HER2/neu oncogenes in breast cancer cells is associated with resistance to the cytotoxic effect of tumor necrosis factor (TNF), we investigated whether this correlation also existed for ovarian cancer targets.
Amplification of the Neu oncogene (c-erbB-2) has been reported by various researchers as a marker for poor clinical outcome in patients with breast cancer.
Among the neoplasms assayed p185 HER2 was expressed in 46% of primary breast cancers, in 28% of ovarian tumors and in 30% of colon rectum malignancies.