title: Isolation of human tumor cells that produce cementum proteins in culture.
abstract: We have cultured cells from explants of a human cementum tumor. The cells obtained were multipolar, they formed network-like structures and they were alkaline-phosphatase positive. Immunostaining and Western blots using specific antibodies revealed that these cells produced bone sialoprotein and collagen types I and V, and they also mineralized in vitro. Conditioned medium was mitogenic to fibroblasts and mitogens present were separated by heparin-affinity chromatography. Based on affinity to heparin and antibody-inhibition studies, the heparin fractions were shown to contain cementum-derived growth factor, platelet-derived growth factor and fibroblast growth factors. The cementum tumor cells, but not gingival fibroblasts, were stained positively by an antibody to cementum-derived attachment protein. The attachment protein was separated by immunoaffinity chromatography, and Western blots revealed that the preparation contained 56-kDa and 43-kDa proteins as major bands. Cells pulse-labeled with radioactive amino acids contained a 43-kDa protein as the major component; however, this protein was absent after a cold chase in the presence of cycloheximide, but 56-kDa, 39-kDa and 26-kDa species became prominent. These data indicated that the 56-kDa cementum attachment protein is derived from a 43-kDa precursor. Our data show that the cells cultured from the cementum tumor represent cementum cells capable of synthesizing and secreting cementum proteins in culture.
authors.affiliation: Department of Pathology SM 30, University of Washington School of Medicine, Seattle 98195.
authors.forename: H
authors.initials: H
authors.lastname: Arzate
authors.forename: S W
authors.initials: SW
authors.lastname: Olson
authors.forename: R C
authors.initials: RC
authors.lastname: Page
authors.forename: A S
authors.initials: AS
authors.lastname: Narayanan
mesh_terms: D000469:Alkaline Phosphatase / Q000378:metabolism; D000906:Antibodies; D015153:Blotting, Western; D002846:Chromatography, Affinity; D003094:Collagen / Q000032:analysis; D003739:Dental Cementum / Q000378:metabolism* / Q000473:pathology; D004591:Electrophoresis, Polyacrylamide Gel; D006133:Growth Substances / Q000096:biosynthesis*; D006801:Humans; D058574:Integrin-Binding Sialoprotein; D009808:Odontogenic Tumors / Q000378:metabolism* / Q000473:pathology; D014176:Protein Biosynthesis; D012795:Sialoglycoproteins / Q000032:analysis; D014407:Tumor Cells, Cultured / Q000166:cytology / Q000378:metabolism*
chemical_list: D000906:Antibodies; D006133:Growth Substances; C546871:IBSP protein, human; D058574:Integrin-Binding Sialoprotein; D012795:Sialoglycoproteins; D003094:Collagen; D000469:Alkaline Phosphatase