Eltrombopag spares Stat3 phosphorylation. Flow cytometric phosphoprotein analysis of MDS/AML cells treated with either 0 or 3 μg/mL Eltrombopag or 100 ng/mL hrTPO. (A) Representative histogram plot. Cells were prestarved in serum-free RPMI medium for 4 hours, treated with Eltrombopag or hrTPO for 60 minutes, fixed, permeabilized, stained with phospho-specific antibodies against p-Stat3 and p-Stat5, and analyzed by FACS. (B) Mean values and SD of p-Stat5 and p-Stat3 analysis of 4 MDS/AML samples upon treatment with either Eltrombopag or hrTPO. ***Statistical significance (P < .001).