Although the human neu gene was shown to be amplified/overexpressed in a large portion of human breast and ovarian cancer, no reports indicate that the human neu gene is activated by a point mutation in human tumor.
Overexpression of the EGFR and c-erbB-2 oncoproteins was found in respectively 3/31 (9%) and 10/31 (32%) ovarian carcinomas, 13/18 (72%) and 7/18 (38%) cervical carcinomas, and 2/15 (13%) and 2/15 (13%) endometrial carcinomas.
Amplification of ERBB-2 was detected in 14 out of 63 (22%) cases of breast carcinoma, in 1 out of 23 patients with ovarian cancers, in 1 out of 19 cases of colon carcinoma and in 1 out of 27 patients with thyroid cancer.
Amplification of the HER-2 (c-erbB-2) gene and overexpression of the p185HER-2 gene product is found in approximately one-third of primary human breast and ovarian cancers and is associated with a poor clinical outcome of early relapse and death.
The finding that erbB2 product in ovarian cancer is mostly localised in cytoplasm and not in the membrane as in breast cancer and that it has a lower molecular weight than the p185 in breast cancer suggest that this oncogene plays a different biological role in these two neoplasms.
No genomic rearrangements by Southern blotting were seen in the brcAI candidate gene estradiol 17 beta dehydrogenase 2 (17hsd2), or in erbB2, prohibition (phb) and nmeI (previously nm23-HI).
Expressions of nm23 gene products/nucleoside diphosphate kinases, epidermal growth factor receptor, erbB-2 protein, and sex steroid receptor status in ovarian carcinomas were also examined by immunohistochemistry.
These data suggest that amplification of the C-erbB-2 gene may play a role in the pathogenesis of ovarian carcinoma; it is frequently observed in advanced ovarian cancer and is associated with poor prognosis for these patients.
Overexpression of HER-2/neu, a 185-kDa tyrosine kinase growth factor receptor, in human ovarian cancers has been correlated with a poor prognosis for survival of the disease.
Approximately 30% of human breast and ovarian cancers have amplification and/or overexpression of HER-2/neu gene which encodes a cell surface growth-factor receptor.