A, Clonogenic survival assays performed after treatment with BiQ2 (at 5 μM in all cell lines but DU-145 which was treated at 2.5 μM) or BiQ11 (at 5 μM for all cell lines) in the presence or absence of 40 μM Dic after exposure to 0, 2 or 4 Gy of ionizing radiation. *P < 0.05 comparing drug treatment with DMSO or drug treatment with DMSO treatment in the presence of Dic at each level of radiation. **P < 0.05 comparing the drug treatment group with the corresponding drug-treated group in the presence of Dic. B, MTT assays after exposure to vehicle (DMSO) or 0.25, 0.5, 1.25, or 2.5 nM of docetaxel in the absence (solid lines, circles) or presence of BiQ2 (at 5 μM for all cell lines but DU-145 which was treated at 2.5 μM, (red lines, squares) or BiQ11 (all cell lines treated at 5 μM (blue lines, triangles).