Cells were exposed to 1 μmol/L AZD1775, 1 μmol/L AZD6738, or both for 24 hours. Then, the cells were harvested, and alkaline comet assay was performed as previously described [11 (link)]. The tail moment and intensity were measured using the Comet Assay IV program (Andor Technology, Belfast, UK). Three independent experiments were analyzed for each condition.