1, 3, 4, 6, 8...1, 3, 4, 6, 8...161015910151, 3, 4, 6, 8...1091, 3, 4, 6, 8...1, 3, 4, 6, 8...1, 3, 4, 6, 8...1, 3, 4, 6, 8...1, 2, 5, 7, 1399G2/M transitionCell-cyclearrestBlocked replicationDNA repairUCN-017-hydroxystaurosporineExogenous:Cigarette SmokeCaffeineRadiation (UV)ClastogenesHypoxiaGenotoxic drugsROSDouble-strand breaksCell-cycle progressionChromatinremodellingSpecialized:Somatic hypermutaionV(D)J recombinationClass switchingChromatin alterationDNA adductAlkylating agentsG1/S transitionG2–MCheckpointCell survivalReplication stressBulky DNA lesionDNA repair and damage preventionEndogenous:Collapsed replication forksSingle stranded DNA replication breaksFree radicals (ROS)ApoptosisG2/M checkpoint arrestBlocked transcriptionSenescenceROSCASP3CREBRAD17GADD45AGADD45AHUS1NBNCCND3CDK5CDK4RFCRAD1CDKN1AMRE11PMAIP1CCNB1CASP9RAD52CCNE2GADD45BFANCD2CHEK1PMLE2F1CHEK2DDB2GADD45GPRKDCCCNE1BRCA1TP53CCNB2BBC3GADD45GPIDDCCND1CDC25ASFNRPA2BIDBAXTLK2RB1CDC25Cc-MycE2F1TNFRSF10BTP53AIP1GADD45BH2AFXATMRB1RAD51RRM2BCaffeineRAD9ACCNB3CYCSATRIPATRCASP8CDKN1BSMC1ACDK2EstradiolAPAF1TLK1CDC2SESN1CCND2ABL1RAD50CDK6FAS