Desmosomal plaque proteins are preserved in all grades of breast cancer. An immunohistochemical study utilizing monoclonal antibodies to desmoplakin.
Using a monoclonal antibody specific for desmoplakin, we evaluated 52 breast carcinomas, 25 normal tissues, 10 benign breast lesions, and 14 nonepithelial tumors. Carcinomas were classified as ductal or lobular, and they were graded histologically according to degree of malignancy and differentiation. Nonepithelial tumors were negative for desmoplakin. All carcinomas stained positively. Desmosomal staining occurred along epithelial cell borders as discrete, punctate granules. Staining intensity was similar in infiltrating carcinomas, in situ carcinomas, benign breast lesions, and normal breast epithelium. Our study demonstrates that most infiltrating breast carcinomas retain abundant desmoplakin, regardless of tumor grade, degree of differentiation, or tumor type (duct or lobular). Although altered desmosomal structure may be important, our findings suggest that loss of desmosomes is not necessary for tumor invasion or metastasis. Desmosomes have a characteristic staining pattern that is easy to interpret, and monoclonal antibodies to desmoplakin may prove useful as markers for distinguishing undifferentiated carcinomas from nonepithelial cancers.
Dervan
P A
PA
Department of Pathology, Mater Misericordiae Hospital, Dublin, Ireland.
Gilmartin
L G
LG
Johnston
P G
PG
Carney
D N
DN
D000911:Antibodies, Monoclonal; D001943:Breast Neoplasms / Q000032:analysis* / Q000473:pathology; D002285:Carcinoma, Intraductal, Noninfiltrating / Q000032:analysis* / Q000473:pathology; D003598:Cytoskeletal Proteins; D051180:Desmoplakins; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008562:Membrane Glycoproteins / Q000032:analysis* / Q000276:immunology; D009361:Neoplasm Invasiveness
D000911:Antibodies, Monoclonal; D003598:Cytoskeletal Proteins; C495294:DSP protein, human; D051180:Desmoplakins; D008562:Membrane Glycoproteins