Functional assay for HER-2/neu demonstrates active signalling in a minority of HER-2/neu-overexpressing invasive human breast tumours.
Overexpression of HER-2/neu in human breast carcinomas correlates with poor prognosis, although its strength as a prognostic indicator varies widely in different reports. Variability may be due to active signalling by HER-2/neu in a subset of the tumours in which it is overexpressed. To study this hypothesis, we have developed an activation state-specific anti-HER-2/neu monoclonal antibody. In this report, we use this antibody to analyse the signalling status of HER-2/neu in a large series of invasive breast carcinomas. Overexpression of HER-2/neu was detected in 9% of 223 cases. Of the cases demonstrating overexpression, active signalling by HER-2/neu was detected in only 35%. The clinicopathological characteristics of these cases are described. This functional assay is predicted to improve the utility of HER-2/ neu as a prognostic indicator.
DiGiovanna
M P
MP
Department of Pathology, Yale University School of Medicine, New Haven, CT 06510, USA.
Carter
D
D
Flynn
S D
SD
Stern
D F
DF
D000911:Antibodies, Monoclonal / Q000032:analysis; D001943:Breast Neoplasms / Q000235:genetics / Q000378:metabolism* / Q000473:pathology / Q000601:surgery; D002278:Carcinoma in Situ / Q000235:genetics / Q000378:metabolism* / Q000473:pathology / Q000601:surgery; D018270:Carcinoma, Ductal, Breast / Q000235:genetics / Q000378:metabolism* / Q000473:pathology / Q000601:surgery; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D007150:Immunohistochemistry / Q000379:methods; D008875:Middle Aged; D011379:Prognosis; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000096:biosynthesis* / Q000235:genetics; D011960:Receptors, Estrogen / Q000032:analysis; D012189:Retrospective Studies; D015398:Signal Transduction / Q000502:physiology*; D013194:Staining and Labeling
D000911:Antibodies, Monoclonal; D018719:Erb-b2 Receptor Tyrosine Kinases; D011960:Receptors, Estrogen