STAT5-IN-2 (100 nM-50 µM) inhibits cell growth in KG1a and MV-4-11 cell lines with EC50 values of 2.6 µM and 3.5 µM, respectively. In K562, KU812, KG1a and MV-4-11 cells, STAT5-IN-2 (10 µM) induces apoptosis. In KG1a, MV-4-11 and KU812 cells, STAT5-IN-2 (10 µM) blocks the phosphorylation of STAT5[1].