Figure 2. High-Throughput Screening and Medicinal Chemistry Identifies ML390 as an Inducer of Myeloid Differentiation.
(A and B) In (A), upon differentiation (following the removal of estradiol), Lys-GFP-ER-HoxA9 GMPs upregulate GFP fluorescence and (B) the cell-surface markers CD11b and Gr-1.
(C) A high-throughput flow cytometry phenotypic screen was established to identify compounds that could trigger differentiation of Lys-GFP-ER-HoxA9 cells as monitored by the upregulation of GFP and CD11b.
(D) Twelve biologically active compounds were identified, including compound 3 (C03) and compound 7 (C07).
(E) The most potent small molecule was a derivative of (R)-C07, designated ML390.
(F) C03 and (R)-C07 triggered myeloid differentiation, while (S)-C07 lacked activity.
(G) ML390 is capable of causing myeloid differentiation in murine (ER-HoxA9) and human (U937 and THP1) AML models.
(H) Imaging flow cytometry demonstrates upregulation of GFP and CD11b expression as well as the downregulation of KIT expression in Lys-GFP-ER-HoxA9 cells during differentiation in the absence of estradiol (-E2) or as the result of treatment with ML390.
See also Figure S2.