Cell CycleCell ProliferationCell AgingCell Cycle ProteinsCell DivisionApoptosisCells, CulturedCell Line, TumorCell Cycle CheckpointsSignal TransductionG1 PhaseCyclin-Dependent Kinase Inhibitor p21Cell DifferentiationTumor Suppressor Protein p53Cell LineMitosisS PhaseFibroblastsCyclinsPhosphorylationBromodeoxyuridineRNA, MessengerRetinoblastoma ProteinCyclin-Dependent Kinase Inhibitor p27Cell SurvivalBlotting, WesternCyclin-Dependent Kinase Inhibitor p16Cyclin D1Flow CytometryGene Expression RegulationTumor Cells, CulturedDown-RegulationRNA, Small InterferingTranscription FactorsTime FactorsProtein-Serine-Threonine KinasesDNA-Binding ProteinsImmunohistochemistryReverse Transcriptase Polymerase Chain ReactionGene Expression Regulation, NeoplasticMolecular Sequence DataProliferating Cell Nuclear AntigenTumor Suppressor ProteinsDNA DamageNuclear ProteinsG2 PhaseMutationTransfectionRNA InterferenceMice, Inbred C57BLCell MovementModels, BiologicalUp-RegulationCell Transformation, NeoplasticG0 PhaseGene ExpressionG1 Phase Cell Cycle CheckpointsDNAKi-67 AntigenMice, KnockoutDose-Response Relationship, DrugCell Growth ProcessesBase SequenceEpithelial CellsCyclin EG2 Phase Cell Cycle CheckpointsPhenotypeCyclin-Dependent Kinase 2Stem CellsLymphocyte ActivationCell NucleusDNA ReplicationMenstrual CycleCyclin-Dependent Kinase 4Transcription, GeneticAntineoplastic AgentsProto-Oncogene Proteins c-mycGene Expression ProfilingProto-Oncogene ProteinsMice, NudeCyclin AAgingEnzyme InhibitorsThymidineEnzyme ActivationAmino Acid SequenceMice, TransgenicGene Knockdown TechniquesTelomereTelomeraseProto-Oncogene Proteins c-aktProtein BindingHeLa CellsGene Expression Regulation, DevelopmentalCDC2 Protein KinaseT-LymphocytesCell CountE2F Transcription FactorsNeoplasmsPromoter Regions, Genetic