Establishment And Characterization Of A Human Osteosarcoma Cell Line(SOSP-M)with High Metastatic Potential To The Lung

Osteosarcoma is the most common malignant bone tumor in adolescents and young adults. Despite recent advances in multimodality treatment consisting of aggressive adjuvant chemotherapy and wide local excision,pulmonary metastasis occurs in approximately 40%-50% of patients with osteosarcoma and remain a major cause of fatal outcome.Therefore, to improve the prognosis of patients with osteosarcoma,prevention of pulmonary metastasis is critical.For this purpose, it is essential to have a good experiental animal model of osteosarcoma with pulmonary metastatic potential and to establishment and characterization of a human osteosarcoma cell line with high metastatic potential to the lung.To establish a new human osteosarcoma spontaneous metastasis model using orthotopic transplantation of histologically intact tumor tissue and screen high metastatic subpopulation from human osteosarcoma cell line SOSP-9607. The SOSP-M was developed fromlung metastatic locus occurred spontaneously through serially orthotopic transplantation of histologically intact tumor tissue into the tibia of nude mice.Cell growth analysis, histological observation, chromosomal staining, human Alu sequence PCR amplification, histochemical staining,flowcytometry and artificial metastasis model in nude mice were employed to characterize the cells.Subline SOSP-M was obtained from SOSP-9607 after 4 selection cycles.Hypotriploid karyotype with human chromosome morphology was observed in SOSP-M. The result of human Alu sequence PCR amplification shows that the metastatic tumor were composed of human osteosarcoma cells. SOSP-M had faster growth speed than SOSP-9607. The rate of S phase cell cycle was21.8 %. CD44 protein positive expression rate were 2 grade and 4 grade respectively.The artificial lung metastasis rate (%) in nude mice of SOSP-9607 and SOSP-M were 10% and 100% respectively.This spontaneous metastasis model of human osteosarcoma in nude mice may resemble a clinical situation and could thus be useful for studies on local tumor growm,metastasis formation and therapy. SOSP-M is a high metastatic subline.