Fig. 4.
Overexpression of TRAF2 or BCL-XL significantly diminishes TL/Btz-induced apoptosis. a–c U266/GFP-TRAF2 and U266/GFP cells were established by stably transfecting cells with full-length human TRAF2 cDNA or empty vector. Cells were treated with Btz +/− TL for 24 h. a Immunoblotting analysis was performed to monitor TRAF2 and p52. GAPDH was assayed to ensure equivalent loading and transfer. Endo, endogenous. b Cytospin slides were prepared, stained with 7-AAD, and counterstained with DAPI. Images were obtained with an IX71-Olympus inverted system microscope at × 200 magnification. c After drug treatment, cells were subjected to flow cytometry to determine the percentage of dead (7-AAD+) cells in GFP+ cells (*P < 0.05; **P < 0.01). Values represent the means ± SD for at least three independent experiments performed in triplicate. d–e U266/BCL-XL and U266/EV cells were established by stably transfecting full-length human BCL-XL cDNA or empty vector. Cells were treated with Btz +/− TL for 24 h. After drug treatment, cells were subjected to flow cytometry to determine the percentage of dead (7-AAD+) cells (**P < 0.01). Values represent the means ± SD for at least three independent experiments performed in triplicate. e Immunoblotting analysis was performed to monitor BCL-XL and PARP. A black line separates images acquired from different regions of the same gel with identical exposures. CF, cleavage fragment. β-actin was assayed to ensure equivalent loading and transfer