APTO-253 Stabilizes G-quadruplex DNA, Inhibits MYC Expression, and Induces DNA Damage in Acute Myeloid Leukemia Cells.

APTO-253 is a phase I clinical stage small molecule that selectively induces CDKN1A (p21), promotes G-G cell-cycle arrest, and triggers apoptosis in acute myeloid leukemia (AML) cells without producing myelosuppression in various animal species and humans. Differential gene expression analysis identified a pharmacodynamic effect on MYC expression, as well as induction of DNA repair and stress response pathways. APTO-253 was found to elicit a concentration- and time-dependent reduction in MYC mRNA expression and protein levels.