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.

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.

MATERIALS AND 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.