Olaparib treatment results in a dose-dependent reduction in survival fraction of SUM-190 (A), MDA-IBC-3 (C), and SUM-149 (E) cell lines. Representative data from single experiments are shown for each cell line. The surviving fraction of cells after 6 Gy (B, D, F) was calculated as the mean of three independent experiments and depicted ± SEM for each cell line. (p < 0.05 = *, p < 0.01 = **)