ERBB2 and breast carcinoma: To investigate the effects of PARP inhibitors in BRCA wild-type breast cancer cell lines with BRCA allelic loss we treated BRCA wild-type ER/PR+, ER+, HER2+, and triple-negative cell lines with 3 different PARP inhibitors, ABT-888, BSI-201, and AZD2281, for 4 days.