title: [Keratin 5-positive cells in the breast are progenitor cells of glandular and myoepithelial differentiation. A cell biological model as a basis of breast pathology].
abstract: In the present computer-assisted labelling study we demonstrate for the first time that in normal breast tissue keratin (K) 5+ progenitor cells give rise to either glandular (K 8/18+) or to myoepithelial cells (sm-actin = SMA+) via intermediary cells (either K 5/6+; K 8/18+ or K 5/6+; SMA+). Furthermore we have conclusive evidence that benign proliferative breast disease lesions are progenitor cell-derived lesions. In contrast, most breast cancers appear to evolve from glandularly differentiated cells. Western blotting experiments which show large amounts of K 5 in benign proliferative breast lesions, but not in ductal carcinoma in situ confirm the immunofluorescence data. Our results pave the way towards a new cell biological model of breast regeneration, benign proliferative breast disease and breast cancer.
authors.affiliation: Gerhard-Domagk-Institut für Pathologie, Universität Münster.
authors.forename: W
authors.initials: W
authors.lastname: Böcker
mesh_terms: D015415:Biomarkers / Q000032:analysis; D001940:Breast / Q000473:pathology*; D002454:Cell Differentiation; D004847:Epithelial Cells / Q000473:pathology*; D005260:Female; D006801:Humans; D053555:Keratin-5; D007633:Keratins / Q000032:analysis*; D008954:Models, Biological; D009375:Neoplasms, Glandular and Epithelial / Q000473:pathology; D013234:Stem Cells / Q000473:pathology*
chemical_list: D015415:Biomarkers; C503940:KRT5 protein, human; D053555:Keratin-5; D007633:Keratins