Studies based on in vivo and in vitro experiments show that Chk1 inhibitors (such as UCN-01, AZD7762) sensitize p53-deficient cancer cells to DNA-damaging agents (such as irinotecan and cisplatin) in different tumor types, including TNBC, head and neck cancer, and pancreatic cancer [173,174,175]. This evidence concerns the gene CHEK1 and cancer.