BRCA2 and breast cancer: To validate the utility of PARPi gene set enrichment and drug ontology enrichment analyses (GSEAs and DOEAs) for PARPi response surrogacy, as well as to select the most sensitive PARPi response gene sets for application to the colorectal (CRC) cohorts, and confirm which HRD state (high versus low) in BC exhibits enrichment for PARPi response, GSEAs were performed with TAI, LOH, LST, and BRCA1 and BRCA2 expression phenotypes for the BC cohorts using 22 PARPi gene sets for olaparib, rucaparib, veliparib and talazoparib.