Fig. 7
From: Small molecules in targeted cancer therapy: advances, challenges, and future perspectives
Molecular process of DNA damage repair related to PARP and the mechanism of action of PARP inhibitors. Endogenous single-strand breaks (SSB) are repaired mostly by PARP-dependent base excision repair (BER) pathway. PARP inhibitors suppress the repair of SSB and the unrepaired SSB can be converted to double-strand breaks (DSB) that are toxic to cells. Homologous recombination (HR) is the major pathway to repair DSB. However, the DSB in BRCA1/2 mutant cells cannot be repaired through HR, thus resulting in genomic instability and cell death. Figure created with BioRender.com
