PARP inhibitors in cancer therapy: an update

Inhibitors of the poly(ADP-ribose) polymerases (PARPs) family of proteins are currently being evaluated as potential anticancer medicines at both preclinical and clinical levels. They have the peculiarity to increase the efficacy of DNA-damaging agents and to selectively target tumor cells with specific DNA repair defects. This later development of these drugs should make it possible, in principle, to selectively target neoplastic vs healthy cells, thus realizing the Ehrlich's magic bullet concept of a personalized and tailored cure of diseases.

This review is designed to provide the readers with a brief summary and an update on PARP inhibitors in the oncology field, by covering the recent patent literature (2010 - 2012: and Questel Intellectual Property Portal [QPat] database search).

Presently, along with a number of preclinical candidates, there are eight PARP inhibitors in the clinic as either single agents or in combination with various chemotherapy and radiotherapy regimens. The tremendous efforts underneath those results testify the high interest on the target. The investigation and understanding of the cross-reactivity among members of the PARPs family as well as a deeper knowledge of their biological functions may lead to a more profound characterization of the PARP inhibitor's profile. This, in turn, will cast additional light on this exciting approach in treating cancer.