Fig. 3: MK-8776/olaparib combination induces DNA damage and cell death in MYCN-OE and MNA cells.

A Upper panels, cell death monitored by trypan-blue exclusion assay in the indicated cells treated with olaparib, MK-8776 and their combination, for 48 h. Data are reported as mean (+SD) of three independent experiments. A Lower panels, WB analysis of whole cell lysates from the indicated cells performed after 9 and 24 h of treatment. Blots were probed with the indicated antibodies; β-actin was used as loading control. Data are representative of at least three replicates. The asterisk indicates the 89-kDa PARP1 cleaved fragment. B Upper panels, Neutral comet assay performed on the indicated cells treated with olaparib, MK-8776 and their combination, for 24 h. DNA damage is quantified by tail moment. Data are reported as mean (+SD) of three independent experiments. B Lower panels, whole cell lysates were analyzed by WB for the expression and/or phosphorylation of the indicated proteins; β-actin was used as loading control. Data are representative of at least three replicates. C Representative Z-stack images captured by confocal microscopy of RAD51 foci in MYCN + cells treated with olaparib, MK-8776 and their combination, for 24 h. Scale bar: 5 µm. D Dot plot representing the mean of RAD51 foci/cell ± SD in MYCN + cells treated as above. Each dot represents a field of at least 50 cells. The graph is representative of two independent experiments. p values were calculated by ANOVA (*p < 0.05, **p < 0.01, ***p < 0.001).