TAK-981, a SUMOylation inhibitor, suppresses AML growth immune-independently.

Acute myeloid leukemia (AML) generally has an unsatisfactory prognosis despite recent introduction of new regimens including targeted agents and antibodies. To find a new druggable pathway, we performed integrated bioinformatic pathway screening on large OHSU and MILE AML databases, discovered the SUMOylation pathway, and validated it independently with an external dataset (totaling 2959 AML and 642 normal sample data). The clinical relevance of SUMOylation in AML was supported by its core gene expression which is correlated with patient survival, ELN2017 risk classification, and AML-relevant mutations. TAK-981, a first-in-class SUMOylation inhibitor currently under clinical trials for solid tumors, showed anti-leukemic effects with apoptosis induction, cell-cycle arrest and induction of differentiation marker expression in leukemic cells. It exhibited potent nanomolar activity, often stronger than that of cytarabine, which is part of the standard-of-care. TAK-981's utility was further demonstrated in in vivo mouse and human leukemia models as well as patient-derived primary AML cells. Our results also indicate direct and cancer-cell-inherent anti-AML effects by TAK-981, different from the IFN1 and immune-dependent mechanism in a previous solid tumor study. Overall, we provide a proof-of-concept for SUMOylation as a new targetable pathway in AML and propose TAK-981 as a promising direct anti-AML agent. Our data should prompt studies on optimal combination strategies and transitions to clinical trials in AML.