OsteosarcomaBone NeoplasmsOsteosarcoma, JuxtacorticalFemoral NeoplasmsCell Line, TumorLeg BonesOsteoblastomaHumerusTumor Cells, CulturedOsteoblastsSarcoma, EwingMethotrexateChondrosarcomaDog DiseasesDoxorubicinGene Expression Regulation, NeoplasticLung NeoplasmsCell ProliferationAntineoplastic AgentsNeoplasm MetastasisApoptosisAmputationCisplatinIfosfamide