Imexon activates an ER stress response. (A) Panc-1, (B) BxPC3, and (C) MiaPaCa-2 were transfected with an ERSE reporter, a negative control, or a positive control for 24h, at which time the cells were washed and then exposed to drugs for an additional 8h with increasing concentrations of imexon. Data shown are the mean ± SEM, n=9 (for MiaPaCa-2 and Panc-1) and n=6 (for BxPC3). *p < 0.05, **p < 0.01.