Chromosome repositioning requires DNA-PKcs activity. Positions of chromosomes 11 and 19 in control, only cisplatin, only DNA-PKcs inhibitor and inhibitor with cisplatin-treated cells as depicted by 3D-FISH (A-F) and 2D-FISH (G-J) analyses. Scale bar: 10 μm. Quantitation as in Figure 1. A delayed repositioning of chromosome 19 territories is observed in damaged cells after removal of the DNA-PKcs inhibitor from the culture medium (K-P) * indicates P = 0.05 as assessed by ANOVA.