Fig. 4

Colony formation attenuated by treatment with talazoparib + decitabine. A–D Representative crystal violet stained culture plate images at day 14, illustrating the effects of Tala, Deci, and combination treatment on colony growth for each M231 BRCA isotype and SUM149PT. Drugs: C, DMSO; T, 5 nM talazoparib; D, 14 nM decitabine; T + D, both drugs. E–H Deci treatment reduces the colonies formed at each Tala dose in all M231 isotypes and SUM149PT. (# indicates the 5 nM Tala ± Deci values for each cell line for comparison). Colony quantitation used BioRad ChemiDoc imaging System (BioRad®), analyzed by ImageJ, values indicate mean ± SEM. I Values from Tala + Deci treatment plotted to directly compare M231 BRCA variants. Non-linear curve fit, asterisks below red icons represent significant differences for M231^BRCA1 versus M231^wt cells, and asterisks beside green icons represent significant differences for M231^BRCA2 versus M231^wt cells. Significance determined by two-way ANOVA with Tukey’s adjustment for multiple testing. ****, p < 0.0001; ***, p < 0.001; **, p < 0.01; *, p < 0.1; ns, not significant. All experiments used at least triplicate samples, and performed at least twice. Prior studies testing colony formation effects of 150 mM azacytidine + 10 nM Tala in M231^wt cells concur with our results. Combination treatment reduced colonies to ~ 60% of controls, while in their SUM149PT controls, colonies were reduced to about 30% of controls