c-erbB2 oncoprotein expression, gene amplification, and chromosome 17 aneusomy in apocrine adenosis of the breast

• Published in: The Journal of pathology Vol. 191; no. 2; pp. 138 - 142
• Main Authors: Selim, A-GA, El-Ayat, G, Wells, CA
• Format: Journal Article
• Language: English
• Published: 01-06-2000
• Subjects: c-erbB-2 gene; chromosome 17
• ISSN: 0022-3417
• DOI: 10.1002/(SICI)1096-9896(200006)191:2<138::AID-PATH611>3.3.CO;2-A

Amplification of the c-erbB2 oncogene and numerical aberrations of chromosome 17 occur in human breast carcinomas. Apocrine adenosis (AA) of the breast has been shown occasionally to have c-erbB2 overexpression and a possible premalignant potential, but little is known about cellular level genetic alterations in AA of the breast. Fluorescene in situ hybridization (FISH) is a new approach to detect these. In this study, a series of AA was studied by immunohistochemistry for c-erbB2 protein expression and by FISH using dual colour DNA probes for the c-erbB2 gene and the centromeric region of chromosome 17. Cell membrane immunostaining was seen in 10/18 (55.6%) AA cases, but unequivocal c-erbB2 gene amplification or chromosome 17 aneusomy was not seen. The results of this study suggest that c-erbB2 overexpression without amplification may occur early in breast oncogenesis. Amplification and numerical chromosome aberrations may occur later in the pathogenesis of apocrine-derived breast carcinomas.