Abstract Outcomes for pediatric acute myeloid leukemia (AML) have improved significantly in recent years. However, relapsed and refractory disease remains a significant problem. The chemotherapy burden experienced by these patients makes the translational development of non-genotoxic experimental therapies attractive. We previously reported that the anti-helminth drug mebendazole induces degradation of the transcription factor MYB and has potent anti-AML activity. In the present study, we use CRISPR drop-out screening to identify genes encoding the proapoptotic regulators BAK and NOXA as hits conferring resistance to mebendazole activity in AML cells. Conversely, targeting MCL1 with a BH3-mimetic significantly enhanced the anti-AML activity of mebendazole in both AML cell lines in vitro and pediatric patient-derived xenograft (PDX) AML cells ex vivo. Treatment of mice transplanted with THP-1 AML cells or aggressive infant PDX AML cells with this drug combination significantly impaired disease progression in vivo. Our data indicate that mebendazole-induced MYB degradation in combination with MCL1 targeting is a novel non-genotoxic therapeutic strategy for pediatric AML.
Tsakaneli et al. (Tue,) studied this question.