title: [Comparison of two different methods for establishing nude mouse model bearing osteosarcoma].
abstract: OBJECTIVE
  To compare two different methods, namely orthotopic implantation and armpit implantation, for establishing nude mouse model bearing osteosarcoma in light of the tumor formation rate and time, tumor growth changes and lung metastasis.
  
  
  METHODS
  Osteosarcoma cells were inoculated in the left armpit or the femoral medullary canal of nude mice, and the tumor growth was observed 6 weeks later. The differences in the pulmonary metastasis were examined macroscopically and microscopically.
  
  
  RESULTS
  Armpit implantation allowed easy operation and fast tumor growth, but tumors often sustained damages by frictions on the surface (P<0.05), and avascular necrosis occurred earlier in the tumors (P<0.05). With this approach, the pulmonary metastasis rate was only 40% (P<0.05), and the metastases in the lungs were sparser (P<0.05) and small. Orthotopic transplantation could well simulate the original growth environment of osteosarcoma, and resulted in milder avascular necrosis and greater pulmonary metastasis rate (100%) with larger and denser metastatic foci. But orthotopic transplantation required more complicated operation for establishing osteosarcoma-bearing models.
  
  
  CONCLUSIONS
  The two methods both result in high tumor growth rate, but orthotopic transplantation is superior in inducing pulmonary metastasis of osteosarcoma and reducing friction injury of the tumor and avascular necrosis in the tumor.
authors.affiliation: Department of Orthopedics and Spine Surgery, Nanfang Hospital, Southern Medical University, Guangzhou 510515, China.
authors.forename: Ming-Qiang
authors.initials: MQ
authors.lastname: Guan
authors.forename: Zhan-Jun
authors.initials: ZJ
authors.lastname: Shi
authors.forename: Peng
authors.initials: P
authors.lastname: Li
authors.forename: Lan-Bo
authors.initials: LB
authors.lastname: Yang
mesh_terms: D000818:Animals; D001859:Bone Neoplasms; D004195:Disease Models, Animal; D051379:Mice; D008807:Mice, Inbred BALB C; D008819:Mice, Nude; D009368:Neoplasm Transplantation / Q000379:methods*; D012516:Osteosarcoma