PARP inhibition: PARP1 and beyond

Recent findings have thrust poly(ADP-ribose) polymerases (PARPs) into the limelight as potential chemotherapeutic targets. What is known about the structures and functions of the family of PARP enzymes and which questions do we need answered to guide the rational development of PARP inhibitors as anticancer agents? Recent findings have thrust poly(ADP-ribose) polymerases (PARPs) into the limelight as potential chemotherapeutic targets. To provide a framework for understanding these recent observations, we review what is known about the structures and functions of the family of PARP enzymes, and then outline a series of questions that should be addressed to guide the rational development of PARP inhibitors as anticancer agents.