title: Simultaneous expression of type IX collagen and an inhibin-related antigen in proliferative myoepithelial cells with pleomorphic adenoma of canine mammary glands.
abstract: To identify an alcian blue-positive component expressed in the early stage of mammary mixed tumor and to pursue the possible involvement of a tumorigenic inducing factor, monoclonal antibodies to type IX collagen were generated and used to investigate the immunohistochemical kinetics of type IX collagen expression by the myoepithelial cell-derived chondrocyte-like cells during the development of chondrometaplasia. We also examined the expression of inhibin-related antigen using antibodies to a synthetic peptide spanning amino acids 1-30 of the inhibin alpha chain. At the earliest stage of chondrometaplasia, where myoepithelial cells began to proliferate inside the basement membrane, the cells expressed type IX collagen together with an inhibin-related antigen which was immunoreactive with the anti-inhibin peptide antibodies. The expression of the inhibin-related antigen was also demonstrated in normal embryonic chondrocytes and myoblasts, but was much less strong in mature chondrocytes and myotubes, strongly suggesting that the inhibin-related antigen is involved in the development of chondrocytes and myoblasts from undifferentiated mesenchymal cells as well as proliferating myoepithelial cells as a chondro-progenitor cell in the mammary mixed tumor. The pathophysiological significance of type IX collagen expression as a possible cell marker of the progenitor cell in myoepithelial cell-related chondrometaplasia is also discussed.
authors.affiliation: Department of Scleroprotein Chemistry and Cell Biology, Faculty of Agriculture, Tokyo University of Agriculture and Technology.
authors.forename: K
authors.initials: K
authors.lastname: Arai
authors.forename: K
authors.initials: K
authors.lastname: Uehara
authors.forename: Y
authors.initials: Y
authors.lastname: Nagai
mesh_terms: D008949:Adenoma, Pleomorphic / Q000737:chemistry / Q000378:metabolism* / Q000473:pathology; D000595:Amino Acid Sequence; D000818:Animals; D000911:Antibodies, Monoclonal; D000918:Antibody Specificity; D000941:Antigens / Q000032:analysis / Q000378:metabolism*; D002356:Cartilage / Q000737:chemistry / Q000378:metabolism*; D002455:Cell Division; D003094:Collagen / Q000032:analysis / Q000378:metabolism*; D004285:Dogs; D004848:Epithelium / Q000737:chemistry / Q000378:metabolism; D007265:Inhibins / Q000032:analysis / Q000276:immunology*; D015674:Mammary Neoplasms, Animal / Q000737:chemistry / Q000378:metabolism* / Q000473:pathology; D008969:Molecular Sequence Data; D010455:Peptides / Q000737:chemistry / Q000378:metabolism*
chemical_list: D000911:Antibodies, Monoclonal; D000941:Antigens; D010455:Peptides; C094377:inhibin-alpha subunit; D007265:Inhibins; D003094:Collagen