ATM and cancer: Moreover, the same author reported that danthron induced DNA damage in GBM 8401 cells via decreasing the expression of DNA damage and repair genes such as ataxia-telangiectasia mutated (ATM), ataxia-telangiectasia and Rad3-related (ATR), breast cancer 1, early onset (BRCA-1), 14-3-3 proteins sigma (14-3-3σ), DNA-dependent serine/threonine protein kinase (DNA-PK), and O6-methylguanine-DNA methyltransferase (MGMT) [57].