PTPN11 and mast cell leukemia: To test whether SHP2 inhibitor could be effective in combination with multi-kinase inhibitor Dasatinib (BMS-354825), previously used in human mast cell leukemia SM patients [16, 37, 39], we treated HMC-1 cells with an IC50 dose of Dasatinib (50 nM) alone, or in combination with two different doses of II-B08.