Leukemia L1210Leukemia P388Leukemia Virus, MurineLeukemia, ExperimentalMoloney murine leukemia virusCell LineInterleukin-3Leukemia L5178LeukemiaTrimetrexateTumor Cells, CulturedCell DivisionPteroylpolyglutamic AcidsCell Line, TumorLeukemia, Myeloid, AcuteFolic Acid AntagonistsAKR murine leukemia virusFriend murine leukemia virusHematopoietic Stem CellsTransfectionInterleukin-2HL-60 CellsDrug ResistanceAbelson murine leukemia virusMethotrexateCell SurvivalAntineoplastic AgentsMolecular Sequence DataBase SequenceLeukemia, LymphoidLeukemia, MyeloidLeukemia, Lymphocytic, Chronic, B-CellDose-Response Relationship, DrugApoptosisRetroviridae InfectionsCells, CulturedLeukemia, Myelogenous, Chronic, BCR-ABL PositiveDoxorubicinLeukemia, Monocytic, AcuteRNA, MessengerStructure-Activity RelationshipCell Line, TransformedCell DifferentiationK562 CellsRauscher VirusGene Expression Regulation, LeukemicLeukemia, T-CellKineticsMice, Inbred AKRLeukemia, Promyelocytic, AcuteAmino Acid SequencePrecursor Cell Lymphoblastic Leukemia-LymphomaRetroviridaeLeukemia, Megakaryoblastic, AcuteSignal TransductionLeukemia, B-CellTranscription, GeneticTime FactorsFlow CytometryXenotropic murine leukemia virus-related virusNeoplasm ProteinsMink Cell Focus-Inducing VirusesDrug Screening Assays, AntitumorDNA, Viral