Cotreatment with PS enhances TG-mediated inhibition of JAK2 downstream signaling and induction of apoptosis in Ba/F3 cells with ectopic overexpression of JAK2V617F. (A) Ba/F3-JAK2V617F and Ba/F3-hEpoR cells were treated with the indicated concentrations of TG and/or PS for 48 hours. After treatment, the cells were washed with 1 × PBS and stained with annexin-V and propidium iodide, and the percentages of apoptotic cells were determined by flow cytometry. Columns represent mean of 3 independent experiments; bars represent SEM. (B-C) Ba/F3-JAK2V617F and Ba/F3-hEpoR cells were treated with the indicated concentrations of TG and/or PS for 24 hours. After this, cell lysates were prepared and immunoblot analyses were performed for pJAK2 (Tyr1007/1008), JAK2, pSTAT5 (Tyr694), STAT5, pSTAT3 (Tyr705), STAT3, pAKT (Ser473), and AKT. The expression levels of β-actin in the lysates served as the loading control. A vertical line has been inserted to indicate a repositioned gel lane.