Fig. 3
From: The synthetic lethality of targeting cell cycle checkpoints and PARPs in cancer treatment
Potential mechanisms of PARP inhibitor resistance. In a clinical setting, the mechanisms of resistance to PARP inhibitors (PARPi) present heterogeneity and mainly consist of a restoration of homologous recombination (HR) ability; b protection of replication fork stability; c reduction in PARP1 trapping; d mutations in cell cycle components; e efflux of the PGP-mediated drug pump; f interference in the microRNA (miRNA) environment