title: Immunoexpression of HER family, neuregulin, MAPK and AKT in invasive ductal carcinomas of the breast.
abstract: 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.
authors: Department of Pathology, Marmara University Hospital, Istanbul, Turkey. hkaya@superonline.com
authors: H
authors: H
authors: Kaya
authors: I
authors: I
authors: Erbarut
authors: N
authors: N
authors: Ozkan
authors: N
authors: N
authors: Bekiroğlu
authors: S
authors: S
authors: Sen
authors: U
authors: U
authors: Abaciğlu
mesh_terms: 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
chemical_list: D014408:Biomarkers, Tumor; D020880:Neuregulins; D011960:Receptors, Estrogen; D011980:Receptors, Progesterone; D066246:ErbB Receptors; D011505:Protein-Tyrosine Kinases; D020928:Mitogen-Activated Protein Kinases