BRCA1 and neoplasm: Clinically, PARP inhibitors could have potential as chemo- and radiosensitizing agents and the demonstration that PARP inhibitors are selective for tumour cells with homologous recombination (HR) gene defects (such as loss-of-function BRCA1 or BRCA2 mutations), suggests that these molecules could have some utility as single agents [reviewed in (Lord & Ashworth, 2012)].