Fig. 5

PARP activity, global DNA methylation and hydroxymethylation in niraparib treated NIH3T3 cells and in PARP^−/− cells. a PARP activity was evaluated by ELISA-based assay. Results were scaled to control NIH3T3 cells and are shown as mean ± SEM (n = 3). Statistical significance was evaluated by ANOVA (with blocking by sets of samples processed together) followed by a Dunnett test comparing each group to the control group. b Global level of DNA methylation was evaluated by an ELISA-based assay. Based on the absorbance measured for the standards, the calibration curve was approximated via a second-order logarithmic regression equation. The percentage of 5mC in the tested samples was calculated from the calibration curve. Results are presented as mean ± SEM (n = 3). Statistical significance was evaluated by ANOVA (with blocking by sets of samples processed together) followed by a Dunnett test comparing each group to the control group. c Immunocytological detection of 5hmC, with anti-5hmC antibody, by confocal imaging. d Quantification of 5hmC signal in confocal images. Integrated signal density (IntDen) of single nuclei was Log10 transformed and represented by a box-plot and the mean value for each sample was marked (●). Statistical significance was evaluated by nested ANOVA followed by the Tukey post hoc test. All groups are significantly different from each other at p*** ≤ 0.001. *p ≤ 0.05, **p ≤ 0.01, n‐number of independent experiments