A bioluminescent orthotopic mouse model of human osteosarcoma that allows sensitive and rapid evaluation of new therapeutic agents In vivo.

Osteosarcoma (OSA) is the most common primary malignant bone tumor in children, 30% of whom develop lung metastases despite aggressive treatment. Our objective was to develop a mouse model of OSA for preclinical studies that (i) incorporates the natural history of OSA including tumor growth in bone and development of lung metastasis and (ii) is amenable to non-invasive detection methods. A human OSA cell line that expresses high levels of luciferase was created. Following subcutaneous injection, nine out of ten mice showed tumor growth. Eight out of ten mice showed tumor growth following orthotopic injection into the proximal tibia. Thirty percent of mice showed pulmonary metastasis by bioluminescent imaging eight to 10 weeks following orthotopic injection. Animals receiving cisplatin treatment showed reduced tumor volume compared to animals treated with vehicle alone. This model allows real-time detection of tumors and can be used to study mechanisms of OSA metastasis and test new therapeutic agents.