Mathematical modelling using phosphoproteomics data classified leukaemia cells from AML patients as sensitive or resistant to PF-3758309 treatment and identified the phosphorylation of the lysine demethylase PHF2 at Ser705 as an indicator of whether or not patients may respond to PF-3758309, with potential clinical and diagnostic utility. This evidence concerns the gene PHF2 and acute myeloid leukemia.