Fig. 4

The effect of PARP-1 inhibition in combination with ¹³¹I-MIBG treatment. SK-N-BE(2c) (a, b) and UVW/NAT cells (d, e) were treated simultaneously with rucaparib (a, d) or olaparib (b, e) in combination with ¹³¹I-MIBG. Cells were treated with 10 μM rucaparib or olaparib following exposure to ¹³¹I-MIBG at various activity concentrations, for a total of 24 h prior to seeding cells for clonogenic assay. The activity concentrations associated with 50 % cell kill (IC₅₀) and the dose enhancement factors corresponding to 50 % clonogenic kill (DEF₅₀) are shown (c). Data are means ± SEM, n = 3; *p < 0.05 compared to the IC₅₀ in the absence of drug