Different distributions of immunoreactive S100-alpha and S100-beta protein expression in human breast cancer.
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.
Funahashi
H
H
Department of Surgery II, Nagoya University School of Medicine, Japan. hfunahas@tsuru.med.nagoya-u.ac.jp
Koshikawa
T
T
Ichihara
S
S
Ohike
E
E
Katoh
K
K
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
D002135:Calcium-Binding Proteins; D009418:S100 Proteins; C110294:S100A1 protein