Effect of Ser/Thr phosphatase inhibitors on the phosphorylation of survival mediators in CLL. (A) Freshly isolated CLL cells were cultured in the absence or presence of 0.1 µM dasatinib, supplemented with Pic3 and 5 or 20 nM okadaic acid (OA) for 8 hours. After such treatment, cells were lysed and analyzed by western blot (Wb) analysis with antibodies against the phosphorylated and, after stripping, against the nonphosphorylated forms of Lyn, Akt, GSK-3, and SHP-1. (B) Whole B-cell lysates from 20 CLL patients underwent a phosphatase activity assay in the absence or presence of increasing concentrations of OA by using pAkt immunoprecipitated from CLL cells, for 0 and 10 minutes at 37°C. After such treatment, the samples underwent Wb analysis with anti-pAkt and anti-Akt antibodies. Pooled densitometric analyses (arbitrary units) of the Wb bands of the immunoblots are shown. Compared with the control, changes were statistically significant (*P < .01).