Immunoexpression of HER family, neuregulin, MAPK and AKT in invasive ductal carcinomas of the breast.
BACKGROUND
The purpose of this study was to investigate the frequency of expression of the erbB/HER family of growth factor receptors, their ligand neuregulinalpha (NRGalpha) and the most important pathways activated by HER receptors that are mitogen-activated protein kinase (MAPK) and serine/threonine kinase (AKT) in invasive ductal carcinomas of the breast, not otherwise specified (IDC-NOS).


METHODS
59 of the IDC-NOS of the breast were studied for ER, PR, EGFR, c-erbB-2, c-erbB-3, c-erbB-4, neuregulin Ab-3, phospho-AKT, and phospho-p44/42 map kinase using the streptavidin-biotin horseradish method.


RESULTS
Of the 59 tumours, 44 (75%) were ER+, 37 (63%) PR+, four (7%) EGFR+, seven (12%) c-erbB-2+, seven (12%) c-erbB-3+ and 14 (24%) c-erbB-4+alpha. Strong cytoplasmic and/or nuclear immunoexpression was revealed in 17 (29%) cases for NRGalpha, 13 (22%) cases for p-AKT, and nuclear immunoexpression with p-MAPK was found in 17 (29%) cases.


CONCLUSIONS
The results suggest that high-grade breast carcinomas are not only associated with ER/PR- negativity, but seem to be activated by receptor tyrosine kinase growth factors.
Kaya
H
H
Department of Pathology, Marmara University Hospital, Istanbul, Turkey. hkaya@superonline.com
Erbarut
I
I
Ozkan
N
N
Bekiroğlu
N
N
Sen
S
S
Abaciğlu
U
U
D014408:Biomarkers, Tumor; D001943:Breast Neoplasms / Q000378:metabolism* / Q000473:pathology; D018270:Carcinoma, Ductal, Breast / Q000378:metabolism* / Q000473:pathology; D002285:Carcinoma, Intraductal, Noninfiltrating / Q000378:metabolism / Q000473:pathology; D066246:ErbB Receptors / Q000378:metabolism; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism*; D020880:Neuregulins / Q000378:metabolism*; D011505:Protein-Tyrosine Kinases / Q000378:metabolism; D011960:Receptors, Estrogen / Q000378:metabolism; D011980:Receptors, Progesterone / Q000378:metabolism
D014408:Biomarkers, Tumor; D020880:Neuregulins; D011960:Receptors, Estrogen; D011980:Receptors, Progesterone; D066246:ErbB Receptors; D011505:Protein-Tyrosine Kinases; D020928:Mitogen-Activated Protein Kinases