PC-3 (A) and DU-145 (B) cell survival analysis by MTT assay following 48 hour treatment with 0 μM (cross-hatched), 50 μM (diagonal), or 100 μM (stippled) carprofen (Carp). Prior to treatment, cells were co-transfected with a ponasterone A-inducible ecdysone receptor plasmid pVgRxR and ΔICDp75NTR (ICD). Following transfection, cells were incubated in serum containing medium for 18 hours, and then incubated in 1 μM ponasterone A (P) for 24 hours to drive expression of the dominant negative gene products (ICD). Results are expressed relative to the control (0 μM). *, P < 0.001