AD 198 inhibited the phosphorylation of ERK, p38 and JNK in TRAF3
tumor B cells. (A) Phosphorylation of MAPK and Akt analyzed by immunoblot analysis. Mouse or human tumor B cells were cultured in the absence or presence of AD 198 or PEP005 for indicated time periods. Drug concentrations used: 1 μM AD 198 and 0.1 μM PEP005 for 105–8 cells; 4 μM AD 198 and 0.2 μM PEP005 for 8226 cells. Total cellular lysates were prepared, and then immunoblotted for phosphorylated (P-) or total ERK, p38, JNK, and Akt, followed by actin. (B) Quantitation of ERK and p38 phosphorylation. Phosphorylated and total ERK1, ERK2, and p38 bands on immunoblots were quantitated using a low-light imaging system, and the results are presented graphically. The amount of P-ERK1, P-ERK2, or P-p38 in each lane was normalized to the intensity of the corresponding total ERK1, ERK2 or p38 band. The graphs depict ERK and p38 phosphorylation observed in three independent experiments (mean ± SD).