Several DNA damage response-related proteins, such as DNA-PKcs (DNA-dependent protein kinase, catalytic subunit), ATM/ATR (ataxia-telangiectasia mutated and Rad3-related), the MRN complex, PARP family proteins, MDC1, Wee1, LIG4 (ligase IV), CDK1, BRCA1, CHK1, and HIF-1 are potential targets for radiosensitization and could be used to overcome tumor radioresistance [298]. Here, ATM is linked to neoplasm.