Consequently, genes involved in DNA damage processing are targets for tumor therapy.7–10 Ataxia telangiectasia mutated (ATM) together with ataxia telangiectasia and Rad3-related protein (ATR) and DNA-dependent protein kinase catalytic subunit (DNA-PKCS) constitutes the core of the DDR.11 DNA damage agents have shown favorable efficacy in anticancer therapy, which has accelerated the development of cancer chemotherapy. The gene discussed is ATR; the disease is cancer.