PC-3 (A) and DU-145 (B) cell survival analysis by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay following 48 h treatment with 0 μmol/L (cross-hatched), 50 μmol/L (diagonal), or 100 μmol/L (stippled) carprofen (Carp). PC-3 (A) and DU-145 (B) cell survival analysis by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay following 48 h treatment with 0 μmol/L (cross-hatched), 50 μmol/L (diagonal), or 100 μmol/L (stippled) carprofen (Carp). Before treatment, cells were cotransfected with a ponasterone A-inducible ecdysone receptor plasmid pVgRxR and ΔICDp75NTR. Following transfection, cells were incubated in serum-containing medium for 18 h and then incubated in 1 μmol/L ponasterone A (P) for 24 h to drive expression of the dominant-negative gene products. Results are expressed relative to the control (0 μmol/L). *, P < 0.001. Fatima S. Khwaja et al. Mol Cancer Ther 2008;7:3539-3545 ©2008 by American Association for Cancer Research