Figure 2. Syk inhibition by TAK-659 downregulates BCR signalling in Ramos and primary CLL cells.

(A–B) Phosphorylation of Syk and ERK1/2 were analyzed by Western Blot in Ramos cells incubated with increasing doses of TAK-659 for 1 hour and stimulated with anti-IgM for 5 minutes. (C–D) Phosphorylation of Syk, Btk, NFκB, ERK1/2 and STAT3 were analyzed by Western Blot in primary CLL cells pre-treated with increasing doses of TAK-659 for 1 hour and stimulated with anti-IgM for 5 minutes. (E–F) Primary CLL cells pre-treated with increasing doses of TAK-659 for 1 hour were co-cultured with BMSC, CD40L and CpG ODN for 15 minutes and anti-IgM stimulated for additional 4 minutes. H₂O₂ 3.3 mM was added for 4 minutes. Expression of phosphorylated Syk, Btk, NFκB, Akt, ERK1/2 and STAT3 was analyzed by western blot. PV: treatment with pervanadate