DNA synthesis inhibition via cytotoxic damage from ionizing radiation

The phrase "DNA synthesis inhibition via cytotoxic damage from ionizing radiation" describes the suppression of replicative DNA synthesis as a result of DNA lesions—predominantly double-strand breaks—caused by ionizing radiation such as X-rays or gamma rays. This leads to activation of cell cycle checkpoints (notably the S-phase checkpoint) in order to halt cell division and allow for attempted DNA repair. If the damage is irreparable or the checkpoint is defective (such as in ataxia-telangiectasia), cells may proceed with damaged DNA, leading to cell death or mutations. This is a key mechanism underlying both the therapeutic efficacy of radiotherapy in cancer and its side effects on normal tissue[3][5][2].

Other names

DNA replication arrest due to radiationRadiation-induced S-phase checkpoint activationDNA synthesis inhibition by ionizing radiationS-phase checkpoint activation by DNA double-strand breaks

Induction of DNA double-strand breaks (DSBs) and other DNA lesions; Activation of cell cycle checkpoints (especially S-phase checkpoint via ATM/CHK2/CDC25a pathway); Activation of cell death pathways through overwhelming of DNA repair mechanisms[5][6][1]