In this study, we assessed the predictive potential of the BRCA1 foci test, similar to the RAD51 foci assay, in a large collection of 55 well-characterized ovarian carcinoma patient-derived xenograft (OC-PDX) models (Supplementary Table S1), whose response to cisplatin (DDP) and olaparib, a PARPi, is known (Ricci et al., 2014). Here, BRCA1 is linked to ovarian carcinoma.