SN-38 Sensitizes BRCA-Proficient Ovarian Cancers to PARP Inhibitors through Inhibiting Homologous Recombination Repair

Figure 3

SN-38 and PARP inhibitor olaparib synergistically induces DNA damage and DNA replication stress. (a) A2780 cells were treated with the indicated concentration of olaparib and SN-38 for 24 hrs, followed by a comet assay of DNA damage. Representative image (left) and quantification of tail moments (right) were represented. (b) OVCAR-3 cells and A2780 cells were treated with indicated compounds, followed by western blot (b) and immunostaining (c, d) analysis of γH2AX. Scale bar is 25 μM. The percentage of γ-H2AX-positive cells (≥5 foci) and the number of γ-H2AX foci per cell was determined by counting at least 100 cells from each sample. Data were represented as the , per group. and , by 2-tailed -test.

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