Cell Viability Assay with DNA-damaging Agents

Camptothecin (TopoGEN, Inc.), olaparib (AZD-2281, Astrazeneca), etoposide (VP16, Funakoshi), ICRF-193 (Funakoshi) and cis-diamminedichloroplatinum(II) (cisplatin, Nippon Kayaku) were used for the sensitivity assay, as described previously [27 (link)–30 (link)]. 10⁴ cells were plated in duplicate onto 24-well cluster plates containing 1m of complete medium supplemented with the above-mentioned reagents and further incubated for 48 h. 3 × 10⁵ cells were exposed to UV or irradiated by a ¹³⁷Cs γ-ray source. 10⁴ cells were then plated in duplicate onto 24-well cluster plates containing 1m of complete medium and culture for 48 h. 100 μl of incubated cell were transferred to 96-well plates and measured the amount of ATP using CellTiter-Glo (Promega), according to the manufacturer's instructions. Luminescence was measured by Fluoroskan Ascent FL (Thermo Fisher Scientific Inc, Whaltham, MA)