(E,E)-bisantrene suppresses MYC expression and displays anti-leukemic activity in acute myeloid leukemia
Background: Acute myeloid leukemia (AML) is genetically diverse with a high unmet clinical need for improved treatment options. Dysregulation of the transcription factor MYC plays a central role in AML progression and therapeutic resistance. (E,E)-bisantrene was recently found to inhibit MYC transcription and downstream activity via G-quadruplex DNA stabilization. This study aimed to evaluate the mechanism of action and preclinical activity of (E,E)-bisantrene in AML. Methods: The in vitro and in vivo activity of (E,E)-bisantrene was determined in a variety of AML models (cell lines, xenograft mouse models, and ex vivo human AML mononuclear cells). Transcriptomic, proteomic and phosphoproteomic analyses were performed after treatment with (E,E)-bisantrene. Analyses of -omics data to identify enriched pathways and upstream regulators were performed. Results: (E,E)-bisantrene demonstrated potent anti-proliferative activity across a panel of AML cell lines, inducing apoptosis and reducing S phase proportions. (E,E)-bisantrene significantly prolonged survival in cell- and patient-derived xenograft models of AML. Mechanistically, RNA-seq and proteomic analysis of MOLM13 and MV4-11 cells treated with (E,E)-bisantrene showed significant reductions in the activity of MYC and E2F, together with the cell cycle regulators CDK1/2/4/5. Transcript and protein levels of MYC were reduced in a dose- and time-dependent manner. TP53 and inflammation-associated transcript signatures were also observed. Conclusion: Anti-proliferative activity of (E,E)-bisantrene in preclinical AML models was associated with a downregulation of MYC, CDK1/2/4/5 and E2F. This study supports the ongoing clinical evaluation of (E,E)-bisantrene in AML where MYC is a clinically relevant driver of disease aggressiveness and therapy resistance.