Editor’s summary
Chemotherapy for acute myeloid leukemia (AML) can result in cardiotoxicity. Pan et al. found that the angiotensin II receptor type 1 (AGTR1) was increased in the blood from patients with AML or with cardiovascular disease and that it could be targeted to both enhance chemotherapy and protect against cardiotoxicity in mouse models. Genetic deletion of the receptor in a human AML cell transplant mouse model and in two other genetic mouse models of AML resulted in decreased leukemic burden and increased survival. Treating mice with losartan, an AGTR1 inhibitor, both enhanced the efficacy of chemotherapy against AML and prevented cardiotoxicity associated with the chemotherapy treatment. Together, these findings demonstrate that AGTR1 may be a target for improving AML treatment. —Brandon Berry.
Abstract
Clinical treatment of acute myeloid leukemia (AML) largely relies on intensive chemotherapy. However, the application of chemotherapy is often hindered by cardiotoxicity. Patient sequence data revealed that angiotensin II receptor type 1 (AGTR1) is a shared target between AML and cardiovascular disease (CVD). We found that inhibiting AGTR1 sensitized AML to chemotherapy and protected the heart against chemotherapy-induced cardiotoxicity in a human AML cell–transplanted mouse model. These effects were regulated by the AGTR1-Notch1 axis in AML cells and cardiomyocytes from mice. In mouse cardiomyocytes, AGTR1 was hyperactivated by AML and chemotherapy. AML leukemogenesis increased the expression of the angiotensin-converting enzyme and led to increased production of angiotensin II, the ligand of AGTR1, in an MLL-AF9–driven AML mouse model. In this model, the AGTR1-Notch1 axis regulated a variety of genes involved with cell stemness and chemotherapy resistance. AML cell stemness was reduced after Agtr1a deletion in the mouse AML cell transplant model. Mechanistically, Agtr1a deletion decreased γ-secretase formation, which is required for transmembrane Notch1 cleavage and release of the Notch1 intracellular domain into the nucleus. Using multiomics, we identified AGTR1-Notch1 signaling downstream genes and found decreased binding between these gene sequences with Notch1 and chromatin enhancers, as well as increased binding with silencers. These findings describe an AML/CVD association that may be used to improve AML treatment.
