Abrogation of apoptosis resistance in CEM-R cells by inhibition of NFκB activation. (A) CEM and CEM-R cells were stimulated with TRAIL (0.3 μg/mL) or PMA (50 ng/mL)/Ionomycin (2 μg/mL) (P/I) for 30 minutes and EMSA was performed. Similar results were obtained in two independent experiments. (B) CEM-R cells were stimulated with TRAIL at the concentrations indicated in the presence (•) or absence (○) of LLnL (1.5 μmol/L, 1 hour of preincubation). After 12 hours, apoptosis was measured by forward side scatter analysis and specific apoptosis was calculated. Data are the mean of duplicates with a standard deviation less than 10%. Similar results were obtained in three independent experiments. (C) CEM-R cells were incubated with doxorubicin in concentrations indicated in the presence (•) or absence (○) of LLnL (1.5 μmol/L, 1 hour of preincubation) for 48 hours. Apoptosis was measured as in (A). Data are the mean of duplicates with a standard deviation less than 10%. Similar results were obtained in three independent experiments. (D) CEM-R cells (5 × 10⁷) were transfected as in (Fig 3D). Stimulation was performed using TRAIL (1 μg/mL), anti–APO-1 (0.01 μg/mL), or TNFα (0.3 μg/mL) and apoptosis was measured after 12 hours of incubation. Data are the mean of duplicates with a standard deviation less than 10%. Similar results were obtained in two independent experiments.