Inhibition of heme biosynthesis triggers cuproptosis in acute myeloid leukemia.

The ubiquitous metabolite heme has diverse enzymatic and signaling functions in most mammalian cells. Through integrated analyses of mouse models, human cell lines, and primary patient samples, we identify de novo heme biosynthesis as a selective dependency in acute myeloid leukemia (AML). The dependency is underpinned by a propensity of AML cells, and especially leukemic stem cells (LSCs), to downregulate heme biosynthesis enzymes (HBEs), which promotes their self-renewal. Inhibition of HBEs causes the collapse of mitochondrial Complex IV and dysregulates the copper-chaperone system, inducing cuproptosis, a form of programmed cell death brought about by the oligomerization of lipoylated proteins by copper. Moreover, we identify pathways that are synthetic lethal with heme biosynthesis, including glycolysis, which can be leveraged for combination strategies. Altogether, our work uncovers a heme rheostat that is connected to gene expression and drug sensitivity in AML and implicates HBE inhibition as a trigger of cuproptosis.