Figure 1.

(A) Clonogenic survival assay for AZD6738 in 231control and XRCC1_KO cells untreated or pre- treated with olaparib (5 μM). (B) Quantification of γH2AX levels by flow cytometry in 231control, 231 (XRCC1_KO) and 157 cells treated with AZD6738 (5 μM) or treated with AZD6738 (5 μM) plus olaparib (5 μM) for 24 h. (C) Quantification of cell cycle progression by flow cytometry in 231control, 231 (XRCC1_KO) and 157 cells treated with AZD6738 (5 μM) or treated with AZD6738 (5 μM) plus olaparib (5 μM) for 24 h. (D) Quantification of apoptotic cells by annexin V flow cytometry in 231control, 231 (XRCC1_KO) and 157 treated with AZD6738 (5 μM) or treated with AZD6738 (5 μM) plus olaparib (5 μM) for 24 h. Cells were plated overnight then treated with 5 μM of olaparib or left untreated for 24 h. The next day, untreated and olaparib pre-treated cells were treated with 5 μM of AZD6738 for another 24 h. After incubation cells were collected by trypsinization and stained for flow cytometry analysis as described in the Methods section. (E) Clonogenic survival assay for olaparib in 231control and XRCC1_KO cells untreated or pre-treated with olaparib. (F) Quantification of γH2AX levels by flow cytometry in 231control, 231 (XRCC1_KO) and 157 cells treated with olaparib. (G) Quantification of cell cycle progression by flow cytometry in 231control, 231 (XRCC1_KO) and 157 cells treated with olaparib. (H) Quantification of apoptotic cells by annexin V flow cytometry in 231control, 231 (XRCC1_KO) and 157 treated with olaparib. (I) Clonogenic survival assay for HeLa control and HeLa (XRCC1_KD) cells untreated or olaparib pre-treated (5 μM) in different doses of AZD6738. (J) Quantification of γH2AX levels by flow cytometry in HeLa control and (XRCC1_KO) cells treated with AZD6738 (5 μM) or treated with AZD6738 (5 μM) plus olaparib (5 μM) for 24 h. (K) Quantification of cell cycle progression by flow cytometry in HeLa control and (XRCC1_KO) cells treated with AZD6738 (5 μM) or treated with AZD6738 (5 μM) plus olaparib (5 μM) for 24 h. (L) Quantification of apoptotic cells by annexin V flow cytometry in HeLa control and (XRCC1_KO) cells treated with AZD6738 (5 μM) or treated with AZD6738 (5 μM) plus olaparib (5 μM) for 24 h. Cells were plated overnight then treated with 5 μM of olaparib or left un-treated for 24 h. The next day, untreated and olaparib pre-treated cells were treated with 5 μM of AZD6738 for another 24 h. After incubation cells were collected by trypsinization and stained for flow cytometry analysis as described in the Methods section.

*p ⩽ 0.05; **p ⩽ 0.01; ***p ⩽ 0.001.