In line with previous studies on ATM inhibitors, 29 was more effective in p53-deficient cells.91 It was also demonstrated that treatment of animal orthotropic brainmodels of glioblastoma and lung cancer brain metastasis (>3 h)with 29 at a concentration above the IC50, in combinationwith ionizing radiation, blocked tumor growth. Here, TP53 is linked to glioblastoma.