Figure 8

Sorafenib downregulates the activation of STAT3 in CLL cells. (A) CLL cells purified from frozen PBMCs were preincubated with sorafenib (10 µmol/L) or DMSO for 30 min and then seeded on MSCs, as described in Materials and Methods, for 30 min, at which point the cells were harvested, lysed and analyzed by Western blot for the expression of pSTAT3, STAT3 and β-actin as loading and transfer control. Data from one representative CLL samples out of five are shown. (B) Densitometry analysis quantifying the modulation of pSTAT3 expression after sorafenib exposure. The ratio of pSTAT3 over STAT3 protein expression are presented for each of the five CLL patients tested in (A). **Statistically significant difference: P < 0.01 (paired Student t test).