Effect of U0126 on CpG-ODN–treated CLL cells. CLL cells (n = 6) were pretreated with 10μM U0126 or DMSO for 15 minutes, before stimulation with CpG-ODN (7μg/mL) for 3 or 48 hours. (A) Representative analysis of BrdU and 7AAD staining in untreated (top) and CpG-ODN (bottom)–treated CLL cells (48 hours). S-phase and dead cells are gated in the bottom panel. (B) Quantitation of S-phase (48 hours, in the presence or absence of CpG-ODN ± U0126. (C) Immunoblot analysis of MYC, phosphorylated ERK1/2, and β-actin expression at 3 hours.