ATR and urinary bladder cancer: One target of interest in bladder cancer is the DNA-damage response (DDR) system, a network of inter-connected signaling pathways which detects and repairs DNA damage, thus promoting cell survival.6–8 Ataxia telangiectasia mutated (ATM) and ataxia telangiectasia and Rad3-related (ATR) are members of the phosphatidylinositol 3-kinase-related kinase (PI3K) family of serine/threonine protein kinases which play an integral role in DDR.