Fig. 8: CX-5461 cooperates with PARPi in inhibiting HGSOC cell growth.

a Mini drug screen in OVCAR4 cells treated with increasing doses of cisplatin (0–1.11 μM), PARPi (BMN-673, 0–0.11 μM), ATMi (KU55933, 0–1.11 μM), ATRi (VE-821, 0–1.11 μM), ABT-119 (0–1.11 μM) or Everolimus (0-0.11 μM) ± 80 nM (GI₂₀) CX-5461. Colour-coding denotes the level of proliferation as measured by DAPI staining and imaging using Cellomics (green denotes reduced proliferation). Dose response of single drug treatments were corrected for vehicle control and the combination was corrected for response to 80 nM CX-5461, the average values of n = 5 are presented. The combination of CX-5461 with BMN-673 or ATRi is highlighted by yellow boxes. b Quantitation of SubG1 DNA content by PI staining of cells treated with vehicle, 100 nM CX-5461, 1 μM VE-821, 100 nM BMN-673 or in combination for 7 days (n = 3 biologically independent experiments). Error bars represent mean ± SEM. Flow cytometry gating strategy is shown in Supplementary Fig. 3D. C) Representative BMN-673 dose response curves ± 30 nM CX-5461. Cell proliferation was measured using SRB assays at 5 days post-treatment. Dose response curves for BMN-673 were corrected for DMSO treatment control and the combination was corrected for response to 30 nM CX-5461. Representative of three biological replicates. Error bars represent mean ± SEM of n = 5 technical replicates. d BrdU cell cycle analysis of cells treated with vehicle, 1 μM CX-5461, 100 nM BMN-673 or in combination for 72 h as described in Fig. 3b and Supplementary Fig. 3D. n = 3, mean ± SEM. e In vitro proliferation time-course assessed by cell confluency using IncuCyte ZOOM. Representative of n = 3 biological replicates, mean ± SEM of five technical replicates. Dashed lines denote re-supplement of media with drugs. f CX-5461 and BMN-673 cooperate in inhibiting clonogenic survival. Representative image of n = 6 biologically independent experiments for OVCAR8 and OVCAR8 RAD51C KO cells and n = 3 biological replicates for FT282 cells, mean ± SEM. g Clonogenic assay of OV90 cells. n = 3 technical replicates. Statistical analysis (in b, d and f) was performed using a two-sided one-way ANOVA, Tukey’s multiple comparisons test (adjusted p-values are shown).