AD 198 did not affect PKCδ nuclear translocation or NF-κB activation. (A) Dose-dependent effects of AD 198. Mouse or human tumor B cells were cultured in the absence or presence of various concentrations of AD 198 for 6 h. (B) Time-dependent effects of AD 198. Mouse or human tumor B cells were cultured in the absence or presence of AD 198 (1 μM for 105–8 cells and 2 μM for 8226 cells) for indicated time periods. Cytosolic and nuclear extracts were prepared as described in the Methods. Proteins were immunoblotted for PKCδ, NF-κB2 (p100 – p52), RelB, NF-κB1 (p50), c-Rel, and RelA, followed by HDAC1 and actin. Immunoblots of actin and HDAC1 were used as loading control for cytosolic and nuclear proteins, respectively. Results are representative of three independent experiments. Similar results were also obtained with other cell lines examined.