MECOM and acute myeloid leukemia: To verify that PIP/56-1 or PIP/56-2 inhibits EVI1-dependent GPR56 expression in EVI1high AML cells, two EVI1low AML cell lines with GPR56 expression, HEL and F36P, were treated with the same series of PIPs and analyzed for GPR56 expression (Supplementary Fig. S1i).