Selective killing of homologous recombination-deficient cancer cell lines by inhibitors of the RPA:RAD52 protein-protein interaction
Fig 5
Mitoxantrone induces apoptosis preferentially in the BRCA1-deficient UWB1.289.
UWB1.289 cells with or without restoration of the BRCA1 expression were treated with 0.2 μM of mitoxantrone (MX) for three days. Olaparib (Ola) at 1 μM was used as control for the induction of apoptosis. Near EC50 concentrations were selected for each compound. After the treatment with each compound, cell lysates were prepared and cleaved PARP was detected with (A) anti-cleaved PARP antibody (Cell Signaling Technology #9541) and (B) anti-PARP antibody (Cell Signaling Technology #9542). Tubulin detected with anti-beta-tubulin antibody (Cell Signaling Technology #15115) was used as an internal control. (C) Ratios of cleaved PARP to tubulin were determined with ImageJ and graphed. Three independent experiments were performed and the mean values are shown. The bars indicate standard deviations. Statistical significance of differences was determined with Student t-test (* p<0.05 and ** p<0.01).