CK2 inhibition-dependent apoptosis of CLL cells correlates with PTEN activation and relies on inactivation of PKC. (A) Cell lysates of normal B cells from healthy donors or primary CLL cells collected at diagnosis were purified and immunoblotted with antibodies against P-PTEN(S380), PTEN, P-PKCβ(S660), P-PKCδ(T550), PKC, or actin as loading control. (B-D) Expression of P-PTEN relative to total PTEN (B) and expression of P-PKCβ (C) and P-PKCδ (D) relative to total PKC was quantified by densitometry analysis. Results are shown as mean ± SEM. (E) Primary CLL cells or JVM-3 cells were incubated with 25μM and 50μM TBB, respectively, and lysed after 2 hours. Cell lysates were immunoblotted with antibodies against the indicated proteins and their phosphorylated forms. P-PTEN results are representative of 10 patients analyzed. P-PKC results are representative of 2 patients analyzed. JVM3 results are representative of 3 independent experiments. (F) MEC1 cells were nucleofected with control versus CK2α siRNA and analyzed at 72 hours for the expression/phosphorylation of the indicated proteins by immunoblot. (G) Primary CLL cells were preincubated with 100nM PMA for 2 hours and then cultured with 12.5μM TBB for 48 hours. Cell viability was assessed by annexin V/7-AAD staining. Results are shown as mean ± SEM of triplicates and are representative of 4 patients analyzed.