title: Influence of vitamin D and retinoids on the induction of functional differentiation in vitro of canine osteosarcoma clonal cells.
abstract: The efficacy of 22-oxacalcitriol (OCT), calcitriol, cholecalciferol, all-trans retinoic acid (ATRA) and 9-cis retinoic acid (9-cis RA) to differentiate in vitro four clonal cells of the canine osteosarcoma cell line POS into cells having properties of a functionally mature osteoblast bone cell were investigated. The induction of intracellular alkaline phosphatase (ALP) activity, osteocalcin (GLA-OC) and type I collagen (PIP) production after 72 h treatment were used as markers of differentiation. At a concentration of 10(-8)M, OCT and calcitriol significantly induced all markers, and ATRA only the ALP of osteoblast, chondroblast and undifferentiated clonal cells. At the same concentration, 9-cis RA and cholecalciferol induced ALP of chondroblast and osteoblast cells, respectively; ATRA, 9-cis RA and cholecalciferol induced PIP of chondroblast and undifferentiated cells. None of the drugs significantly differentiated fibroblast cells. The ability of these agents to differentiate osteosarcoma cells into cells that exhibit properties of functionally mature osteoblastic bone cells may promote normal osteogenesis and reverse the loss of control of their differentiation.
authors.affiliation: Laboratory of Veterinary Surgery, Department of Veterinary Clinical Sciences, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo, 060-0818, Japan. efbm@vetmed.hokudai.ac.jp
authors.forename: E F
authors.initials: EF
authors.lastname: Barroga
authors.forename: T
authors.initials: T
authors.lastname: Kadosawa
authors.forename: M
authors.initials: M
authors.lastname: Okumura
authors.forename: T
authors.initials: T
authors.lastname: Fujinaga
mesh_terms: D000469:Alkaline Phosphatase / Q000096:biosynthesis / Q000187:drug effects; D000818:Animals; D002454:Cell Differentiation / Q000187:drug effects; D002471:Cell Transformation, Neoplastic / Q000187:drug effects; D002999:Clone Cells / Q000187:drug effects; D004283:Dog Diseases / Q000209:etiology*; D004285:Dogs; D004790:Enzyme Induction / Q000187:drug effects; D010006:Osteoblasts / Q000166:cytology* / Q000187:drug effects*; D015675:Osteocalcin / Q000096:biosynthesis / Q000187:drug effects; D012516:Osteosarcoma / Q000209:etiology / Q000662:veterinary*; D010446:Peptide Fragments / Q000096:biosynthesis / Q000187:drug effects; D011347:Procollagen / Q000096:biosynthesis / Q000187:drug effects; D012176:Retinoids / Q000494:pharmacology*; D014407:Tumor Cells, Cultured; D014807:Vitamin D / Q000494:pharmacology*
chemical_list: D010446:Peptide Fragments; D011347:Procollagen; D012176:Retinoids; C042813:procollagen type I carboxy terminal peptide; D015675:Osteocalcin; D014807:Vitamin D; D000469:Alkaline Phosphatase