Effect of Notch activation in myeloma cells on NF-κB and antiapoptotic proteins. (A) H929 cells were incubated on the monolayer of irradiated 3T3-Jagged (J) or control (Con) fibroblasts for 1.5, 3, or 6 hours. Myeloma cells were then collected, and nuclear extract was prepared followed by EMSA with NF-κB-specific probe. Similar results were obtained after H929 cells were collected at other time points: 0.5, 1, 4, 8, 12, and 24 hours. Experiments were performed twice with the same results. (B) H929 cells were incubated on the monolayer of 3T3-Jagged (J) or 3T3-MSCV (Con) stroma for 48 hours. Protein expression was evaluated by Western blotting. Experiments were repeated twice with the same results.