Fig. 7

The effect of PARP-1 inhibition on the persistence of radiation-induced DNA damage. Immunofluorescent confocal microscopy confirmed nuclear localisation of anti-γH2AX Alexa-Fluor 647-labelled antibody (a) following 10 Gy X-radiation treatment (blue, DAPI nuclear stain; green, anti-β-tubulin cytoplasmic antibody visualised using Alexa Fluor 488-conjugated secondary antibody; red, anti-γH2AX Alexa Fluor 647-conjugated antibody). SK-N-BE(2c) (b) and UVW/NAT (c) cells were treated with 10 μM rucaparib, 10 μM olaparib or 3 Gy X-radiation as single agents, or in combination. Cells were harvested 2 and 24 h after irradiation and the total percentage of γH2AX positive cells was analysed using flow cytometry. Representative FACS dot plots obtained from SK-N-BE(2c) cells are shown (d). Data are means ± SEM, n = 3; *p < 0.05, **p < 0.01, ***p < 0.001 compared to untreated cells