Targeting DHODH with AG-636 Induces Apoptosis and Differentiation and Inhibits Mitochondrial Function in AML, Translating into Anti-Tumor Efficacy in Vitro and in Vivo

Autor: Danielle Ulanet, Qi Zhang, Hagop M. Kantarjian, Joshua Murtie, Natalia Baran, Marina Konopleva, Antonio Cavazos, Vinitha Mary Kuruvilla, Philip L. Lorenzi, Michael Andreeff, Zhihong Zeng, Courtney D. DiNardo, Sergej Konoplev
Rok vydání: 2019
Předmět:
Zdroj: Blood. 134:3911-3911
ISSN: 1528-0020
0006-4971
Popis: Background: Acute myeloid leukemia (AML) is a devastating hematopoietic malignancy caused by differentiation arrest and suppression of apoptosis of immature myeloid cells. The long-term survival of AML under the established therapies remains poor. Differentiation therapy has been developed to promote the normal process of hematopoietic maturation from self-renewing progenitors to terminally differentiated effector cells. The recent discovery of a novel target, the enzyme dihydroorotate dehydrogenase (DHODH), offers differentiation-promoting therapy for the majority of AML (Sykes, D.B., et al.Cell, 2016). DHODH is the rate-limiting enzyme in the pyrimidine biosynthesis pathway. DHODH inhibition was reported to efficiently relieve the differentiation block caused by HoxA9 overexpression in 70% of AML, making this discovery potentially universally applicable for AML patients with diverse genomic alterations. AG-636 is a novel, potent, selective DHODH inhibitor developed by Agios Pharmaceuticals. This small molecule inhibitor has favorable pharmacokinetic properties and is in dose-finding Phase I clinical trials in lymphoma patients (NCT03834584) and is ready to enter a Phase I study in acute leukemia and myeloid dysplasia syndrome. Here, we investigated single agent activity of AG-636 in pre-clinical AML models. Results: AG-636 inhibited cell proliferation, induced apoptosis in AML cell lines, primary blasts and CD34+ leukemic stem/progenitor cells from AML patients with various genomic alterations cultured under physiologic conditions of stromal support (Fig. 1A). Flow cytometry and multi-parametric mass cytometry (CyTOF) analysis demonstrated that AG-636 reduced bulk AML and facilitated emergence of the differentiated myelo-monocytic cell subset co-expressing CD11b, CD11c and CD14 (Fig. 1B). Both cytotoxic and differentiating effects were rescued by supplementing the DHO downstream metabolite uridine, supporting on-target activity of AG-636 through DHODH inhibition and dependency of AML survival and stemness on the pyrimidine biosynthesis (Fig 1A top). Mass spectrometric analysis of 166 metabolites confirmed that targeting DHODH by AG-636 resulted in accumulation of the upstream L-dihydroorotic acid and ureidosuccinic acid, and depletion of the downstream metabolites, such as uridine 5'-diphsophate, uridine 5'-monophsophate, CDP and dCMP in pyrimidine biosynthesis pathway. Metabolic profiling further demonstrated the depletion of 5'-phosphoribosyl-N-formylglycinamide in treated cells, indicating the sequential effect of AG-636 on purine biosynthesis and metabolism. Seahorse-based metabolic assay showed inhibition of basal oxygen consumption and ATP generation in AG-636-treated cells, suggesting a contribution of DHODH in coupling of the mitochondria function. Proteomic profiling and immunoblots analysis revealed that AG-636 triggered AMPK activation in response to metabolic stress, and upregulated the expression of TP53, PUMA and NOXA known to regulate mitochondrial integrity. A role for DHODH inhibition in impairment of mitochondria function is of note given the key metabolic dependence of AML cells on OXPHOS/mitochondria function as shown by us and others (Molina J.R. et al. Nat Med, 2018). In vivo, twice daily administration of AG-636 significantly extended survival in a xenograft MOLM13-GFP-luciferase mouse model (Fig. 1C). Flow cytometry and CyTOF analysis demonstrated that AG-636 induced differentiation of CD11b+CD14+ and CD11b+CD11c+CD14+ monocytes in the bone marrow of treated mice (Fig. 1D). Administration of AG-636 significantly reduced tumor burden, induced differentiation and delayed leukemia progression in two AML patient-derived xenograft mouse models, one harboring mutations EZH2, NRAS and TET3, the other with mutations in ASXL1, BCOR and U2AF1. Daily treatment of AG-636 was well tolerated in all xenograft AML models tested, with a minimal effect on body weight and no significant toxicity recorded over the course of regimen. Conclusions: Our preliminary findings demonstrate that AG-636 is highly active against ex-vivo stroma-supported AML and AML stem/progenitor cells and in the in vivo AML xenograft models with diverse genetic subtypes. The significant monotherapy efficacy observed in pre-clinical studies provides the strong rationale for a clinical evaluation of AG-636 in myeloid malignancies. Disclosures Kuruvilla: The University of Texas M.D.Anderson Cancer Center: Employment. Kantarjian:Daiichi-Sankyo: Research Funding; Agios: Honoraria, Research Funding; Astex: Research Funding; Actinium: Honoraria, Membership on an entity's Board of Directors or advisory committees; Amgen: Honoraria, Research Funding; AbbVie: Honoraria, Research Funding; BMS: Research Funding; Takeda: Honoraria; Ariad: Research Funding; Cyclacel: Research Funding; Pfizer: Honoraria, Research Funding; Immunogen: Research Funding; Jazz Pharma: Research Funding; Novartis: Research Funding. Andreeff:Daiichi Sankyo, Inc.: Consultancy, Patents & Royalties: Patents licensed, royalty bearing, Research Funding; Jazz Pharmaceuticals: Consultancy; Celgene: Consultancy; Amgen: Consultancy; AstaZeneca: Consultancy; 6 Dimensions Capital: Consultancy; Reata: Equity Ownership; Aptose: Equity Ownership; Eutropics: Equity Ownership; Senti Bio: Equity Ownership, Membership on an entity's Board of Directors or advisory committees; Oncoceutics: Equity Ownership; Oncolyze: Equity Ownership; Breast Cancer Research Foundation: Research Funding; CPRIT: Research Funding; NIH/NCI: Research Funding; Center for Drug Research & Development: Membership on an entity's Board of Directors or advisory committees; Cancer UK: Membership on an entity's Board of Directors or advisory committees; NCI-CTEP: Membership on an entity's Board of Directors or advisory committees; German Research Council: Membership on an entity's Board of Directors or advisory committees; Leukemia Lymphoma Society: Membership on an entity's Board of Directors or advisory committees; NCI-RDCRN (Rare Disease Cliln Network): Membership on an entity's Board of Directors or advisory committees; CLL Foundation: Membership on an entity's Board of Directors or advisory committees; BiolineRx: Membership on an entity's Board of Directors or advisory committees. DiNardo:celgene: Consultancy, Honoraria; daiichi sankyo: Honoraria; jazz: Honoraria; medimmune: Honoraria; syros: Honoraria; notable labs: Membership on an entity's Board of Directors or advisory committees; abbvie: Consultancy, Honoraria; agios: Consultancy, Honoraria. Murtie:Agios Pharmaceuticals, Inc.: Employment. Ulanet:Agios: Employment, Equity Ownership. Konopleva:Calithera: Research Funding; Stemline Therapeutics: Consultancy, Honoraria, Research Funding; Forty-Seven: Consultancy, Honoraria; Eli Lilly: Research Funding; AbbVie: Consultancy, Honoraria, Research Funding; Cellectis: Research Funding; Amgen: Consultancy, Honoraria; F. Hoffman La-Roche: Consultancy, Honoraria, Research Funding; Genentech: Honoraria, Research Funding; Ascentage: Research Funding; Kisoji: Consultancy, Honoraria; Reata Pharmaceuticals: Equity Ownership, Patents & Royalties; Ablynx: Research Funding; Astra Zeneca: Research Funding; Agios: Research Funding.
Databáze: OpenAIRE