ASXL1 and myeloid leukemia: The human myeloid leukemia cell line KBM5 (derived from a CML patient in blast phase) was chosen for this study as it lacks wild-type ASXL1 protein expression, due to a homozygous point mutation (c.2128G > T, p.G710X) in the ASXL1 gene that creates a premature termination codon [13] (Figure 1A).