CHEK1 and cancer: Thus, using targeted agents for DDR pathways, including inhibitors of ATR/CHK1 [116], PARP [117], ATM, cyclin-dependent kinase 4/6 (CDK4/6), DNA-PK, WEE1, and aurora kinase B (AURKB) [9] opens new exciting avenues for clinical development of ICB for cancer treatment.