title: An in vivo/in vitro experimental model system for the study of human osteosarcoma: canine osteosarcoma cells (COS31) which retain osteoblastic and metastatic properties in nude mice.
abstract: BACKGROUND
  In this report we describe the establishment, characterization, and research utility of a cell line derived from a dog having a spontaneously occurring osteosarcoma.
  
  
  METHODS
  Tumor samples were collected from a dog with a naturally occurring osteosarcoma and processed for light microscopy, electron microscopy, immunocytochemistry, immunohistochemistry, karyology, and cell culture. Established cells from passage 31 (COS31; canine Qsteosarcoma cells from passage 31) were inoculated subcutaneously between the scapula and in the right abdominal side of athymic nude mice and evaluated similarly.
  
  
  RESULTS
  COS31 cells derived in cell culture and in nude mice had morphological and biochemical properties comparable in all respects to the original canine tumor specimen.
  
  
  CONCLUSIONS
  The ability of COS31 cells to produce tumors in nude mice (i.e. a small animal model) typical of canine osteosarcoma (i.e. a large animal model) with a similar pathological and biological behavior (e.g. alkaline phosphatase and osteocalcin positive immunostaining, osteoid production, rapid growth, and wide spread metastases) demonstrates the potential utility of COS31 cells as a in vitro and in vivo model system in the development of new strategies in the treatment of human osteosarcoma.
authors.affiliation: Department of Comparative Medicine, College of Veterinary Medicine, University of Tennessee, Knoxville 37901-1071, USA.
authors.forename: A M
authors.initials: AM
authors.lastname: Shoieb
authors.forename: K A
authors.initials: KA
authors.lastname: Hahn
authors.forename: M A
authors.initials: MA
authors.lastname: Barnhill
mesh_terms: D000469:Alkaline Phosphatase / Q000378:metabolism; D000818:Animals; D001859:Bone Neoplasms / Q000235:genetics / Q000378:metabolism / Q000473:pathology / Q000662:veterinary*; D004195:Disease Models, Animal; D004283:Dog Diseases / Q000235:genetics / Q000378:metabolism / Q000473:pathology*; D004285:Dogs; D005260:Female; D006801:Humans; D007621:Karyotyping; D008297:Male; D051379:Mice; D008819:Mice, Nude; D009368:Neoplasm Transplantation / Q000473:pathology; D009374:Neoplasms, Experimental / Q000473:pathology; D010006:Osteoblasts / Q000473:pathology*; D015675:Osteocalcin / Q000378:metabolism; D012516:Osteosarcoma / Q000235:genetics / Q000378:metabolism / Q000473:pathology / Q000662:veterinary*; D014407:Tumor Cells, Cultured
chemical_list: D015675:Osteocalcin; D000469:Alkaline Phosphatase