title: Different distributions of immunoreactive S100-alpha and S100-beta protein expression in human breast cancer.
abstract: OBJECTIVE
  Although the localization of S100 protein in breast carcinoma has previously been studied, the immunohistochemical expression of the S100-alpha and -beta subunits has not been examined.
  
  
  METHODS
  Immunohistochemical staining for S100-alpha and S100-beta proteins was performed on 72 benign breast lesions and 72 infiltrating ductal carcinoma of the breast. Noncross-reactive anti-S100-alpha and anti-S100-beta antibodies purified by affinity chromatography were used in the studies.
  
  
  RESULTS
  More than 30% of the epithelial cells comprising all the benign lesions were either S100-alpha or S100-beta positive. In breast carcinoma cases, however, >30% of malignant cells were S100-alpha positive in 70/72 cases (97.2%), whereas the number of S100-beta positive cells exceeded 30% in only 3/72 cases (4.0%).
  
  
  CONCLUSIONS
  Immunohistochemical staining for S 100-alpha and S100-beta proteins may help to differentiate benign proliferative breast lesions from breast cancers in difficult cases.
authors.affiliation: Department of Surgery II, Nagoya University School of Medicine, Japan. hfunahas@tsuru.med.nagoya-u.ac.jp
authors.forename: H
authors.initials: H
authors.lastname: Funahashi
authors.forename: T
authors.initials: T
authors.lastname: Koshikawa
authors.forename: S
authors.initials: S
authors.lastname: Ichihara
authors.forename: E
authors.initials: E
authors.lastname: Ohike
authors.forename: K
authors.initials: K
authors.lastname: Katoh
mesh_terms: D001943:Breast Neoplasms / Q000378:metabolism* / Q000473:pathology; D002135:Calcium-Binding Proteins / Q000378:metabolism*; D018270:Carcinoma, Ductal, Breast / Q000378:metabolism* / Q000473:pathology; D002846:Chromatography, Affinity; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D009418:S100 Proteins
chemical_list: D002135:Calcium-Binding Proteins; D009418:S100 Proteins; C110294:S100A1 protein