Fig. 4: Structure-based optimization of ASH1L inhibitors.

a Chemical structures of ASH1L inhibitors developed using structure-based design. b Titration curves and IC50 values from the HMT assay. Data are mean ± s.d. from two independent experiments. c Binding isotherm from the ITC experiment performed for the binding of AS-6 to ASH1L. Data are mean ± s.d. from two independent experiments. A representative binding isotherm is shown. d Mechanistic studies from HMT assay with the IC50 values for AS-6 measured at various nucleosome concentration demonstrating non-competitive inhibition with nucleosome. e Crystal structure of ASH1L-AS-85 complex determined at 1.69 Å resolution. Selected ASH1L residues (gray carbons) and AS-85 (green carbons) are shown in sticks. Hydrogen bonds are shown as dashed lines. f Selectivity of AS-99 tested at 50 µM concentration against a panel of histone methyltransferases. Data represent two independent experiments each performed in duplicates.