Increased tryptophan (Trp) catabolism in the tumor microenvironment (TME) can mediate immune suppression by upregulation of interferon (IFN)-γ-inducible indoleamine 2,3-dioxygenase (IDO1) and/or ectopic expression of the predominantly liver-restricted enzyme tryptophan 2,3-dioxygenase (TDO)1,2,3,4,5. Whether these effects are due to Trp depletion in the TME or mediated by the accumulation of the IDO1 and/or TDO (hereafter referred to as IDO1/TDO) product kynurenine (Kyn) remains controversial5,6,7,8,9,10,11,12,13. Here we show that administration of a pharmacologically optimized enzyme (PEGylated kynureninase; hereafter referred to as PEG-KYNase) that degrades Kyn into immunologically inert, nontoxic and readily cleared metabolites inhibits tumor growth. Enzyme treatment was associated with a marked increase in the tumor infiltration and proliferation of polyfunctional CD8+ lymphocytes. We show that PEG-KYNase administration had substantial therapeutic effects when combined with approved checkpoint inhibitors or with a cancer vaccine for the treatment of large B16-F10 melanoma, 4T1 breast carcinoma or CT26 colon carcinoma tumors. PEG-KYNase mediated prolonged depletion of Kyn in the TME and reversed the modulatory effects of IDO1/TDO upregulation in the TME.
Subscribe to Journal
Get full journal access for 1 year
only $4.92 per issue
All prices are NET prices.
VAT will be added later in the checkout.
Tax calculation will be finalised during checkout.
Rent or Buy article
Get time limited or full article access on ReadCube.
All prices are NET prices.
Cheong, J.E. & Sun, L. Targeting the IDO1–TDO2–KYN–AHR pathway for cancer immunotherapy—challenges and opportunities. Trends Pharmacol. Sci. 39, 307–325 (2018).
Prendergast, G.C., Malachowski, W.P., DuHadaway, J.B. & Muller, A.J. Discovery of IDO1 inhibitors: from bench to bedside. Cancer Res. 77, 6795–6811 (2017).
Munn, D.H. & Mellor, A.L. Indoleamine 2,3-dioxygenase and tumor-induced tolerance. J. Clin. Invest. 117, 1147–1154 (2007).
Badawy, A.A.-B., Namboodiri, A.M.A. & Moffett, J.R. The end of the road for the tryptophan depletion concept in pregnancy and infection. Clin. Sci. (Lond.) 130, 1327–1333 (2016).
Sonner, J.K. et al. The stress kinase GCN2 does not mediate suppression of antitumor T cell responses by tryptophan catabolism in experimental melanomas. OncoImmunology 5, e1240858 (2016).
Van de Velde, L.-A. et al. Stress kinase GCN2 controls the proliferative fitness and trafficking of cytotoxic T cells independent of environmental amino acid sensing. Cell Rep. 17, 2247–2258 (2016).
Platten, M., Wick, W. & Van den Eynde, B.J. Tryptophan catabolism in cancer: beyond IDO and tryptophan depletion. Cancer Res. 72, 5435–5440 (2012).
Puccetti, P. et al. Accumulation of an endogenous tryptophan-derived metabolite in colorectal and breast cancers. PLoS One 10, e0122046 (2015).
Fatokun, A.A., Hunt, N.H. & Ball, H.J. Indoleamine 2,3-dioxygenase 2 (IDO2) and the kynurenine pathway: characteristics and potential roles in health and disease. Amino Acids 45, 1319–1329 (2013).
Spranger, S. et al. Upregulation of PD-L1, IDO and Tregs in the melanoma tumor microenvironment is driven by CD8+ T cells. Sci. Transl. Med. 5, 200ra116 (2013).
Mondanelli, G. et al. A Relay pathway between arginine and tryptophan metabolism confers immunosuppressive properties on dendritic cells. Immunity 46, 233–244 (2017).
Holmgaard, R.B., Zamarin, D., Munn, D.H., Wolchok, J.D. & Allison, J.P. Indoleamine 2,3-dioxygenase is a critical resistance mechanism in antitumor T cell immunotherapy targeting CTLA4. J. Exp. Med. 210, 1389–1402 (2013).
Ninomiya, S. et al. Tumor indoleamine 2,3-dioxygenase (IDO) inhibits CD19-CAR T cells and is downregulated by lymphodepleting drugs. Blood 125, 3905–3916 (2015).
Spranger, S. et al. Mechanism of tumor rejection with doublets of CTLA4, PD-1–PD-L1 or IDO blockade involves restored IL-2 production and proliferation of CD8+ T cells directly within the tumor microenvironment. J. Immunother. Cancer 2, 3 (2014).
Thaker, A.I. et al. IDO1 metabolites activate β-catenin signaling to promote cancer cell proliferation and colon tumorigenesis in mice. Gastroenterology 145, 416–425 (2013).
Mezrich, J.D. et al. An interaction between kynurenine and the aryl hydrocarbon receptor can generate regulatory T cells. J. Immunol. 185, 3190–3198 (2010).
Opitz, C.A. et al. An endogenous tumor-promoting ligand of the human aryl hydrocarbon receptor. Nature 478, 197–203 (2011).
Seok, S.-H. et al. Trace derivatives of kynurenine potently activate the aryl hydrocarbon receptor (AHR). J. Biol. Chem. 293, 1994–2005 (2018).
Theofylaktopoulou, D. et al. A community-based study on determinants of circulating markers of cellular immune activation and kynurenines: the Hordaland Health Study. Clin. Exp. Immunol. 173, 121–130 (2013).
Vécsei, L., Szalárdy, L., Fülöp, F. & Toldi, J. Kynurenines in the CNS: recent advances and new questions. Nat. Rev. Drug Discov. 12, 64–82 (2013).
Cervenka, I., Agudelo, L.Z. & Ruas, J.L. Kynurenines: tryptophan's metabolites in exercise, inflammation and mental health. Science 357, eaaf9794 (2017).
Phillips, R.S. Structure and mechanism of kynureninase. Arch. Biochem. Biophys. 544, 69–74 (2014).
Stone, E. et al. Strategies for optimizing the serum persistence of engineered human arginase I for cancer therapy. J. Control. Release 158, 171–179 (2012).
Frumento, G. et al. Tryptophan-derived catabolites are responsible for inhibition of T and natural killer cell proliferation induced by indoleamine 2,3-dioxygenase. J. Exp. Med. 196, 459–468 (2002).
Hou, D.-Y. et al. Inhibition of indoleamine 2,3-dioxygenase in dendritic cells by stereoisomers of 1-methyl-tryptophan correlates with antitumor responses. Cancer Res. 67, 792–801 (2007).
Banerjee, T. et al. A key in vivo antitumor mechanism of action of natural-product-based brassinins is inhibition of indoleamine 2,3-dioxygenase. Oncogene 27, 2851–2857 (2008).
Levina, V., Su, Y. & Gorelik, E. Immunological and non-immunological effects of indoleamine 2,3-dioxygenase on breast tumor growth and spontaneous metastasis formation. Clin. Dev. Immunol. 2012, 173029 (2012).
Pagès, F. et al. In situ cytotoxic and memory T cells predict outcome in patients with early-stage colorectal cancer. J. Clin. Oncol. 27, 5944–5951 (2009).
Yuan, J. et al. CTLA4 blockade enhances polyfunctional NY-ESO-1-specific T cell responses in metastatic melanoma patients with clinical benefit. Proc. Natl. Acad. Sci. USA 105, 20410–20415 (2008).
Wainwright, D.A. et al. Durable therapeutic efficacy utilizing combinatorial blockade against IDO, CTLA4 and PD-L1 in mice with brain tumors. Clin. Cancer Res. 20, 5290–5301 (2014).
Holmgaard, R.B., Zamarin, D., Lesokhin, A., Merghoub, T. & Wolchok, J.D. Targeting myeloid-derived suppressor cells with colony stimulating factor–1 receptor blockade can reverse immune resistance to immunotherapy in indoleamine 2,3-dioxygenase–expressing tumors. EBioMedicine 6, 50–58 (2016).
Grosso, J.F. & Jure-Kunkel, M.N. CTLA4 blockade in tumor models: an overview of preclinical and translational research. Cancer Immun. 13, 5 (2013).
Schreiber, T.H., Raez, L., Rosenblatt, J.D. & Podack, E.R. Tumor immunogenicity and responsiveness to cancer vaccine therapy: the state of the art. Semin. Immunol. 22, 105–112 (2010).
Chung, K.-T. & Gadupudi, G.S. Possible roles of excess tryptophan metabolites in cancer. Environ. Mol. Mutagen. 52, 81–104 (2011).
Moyer, B.J. et al. Indoleamine 2,3-dioxygenase 1 (IDO1) inhibitors activate the aryl hydrocarbon receptor. Toxicol. Appl. Pharmacol. 323, 74–80 (2017).
Terness, P. et al. Inhibition of allogeneic T cell proliferation by indoleamine 2,3-dioxygenase–expressing dendritic cells: mediation of suppression by tryptophan metabolites. J. Exp. Med. 196, 447–457 (2002).
Sierra, J.R., Cepero, V. & Giordano, S. Molecular mechanisms of acquired resistance to tyrosine kinase targeted therapy. Mol. Cancer 9, 75 (2010).
Matino, D. et al. IDO1 suppresses inhibitor development in hemophilia A treated with factor VIII. J. Clin. Invest. 125, 3766–3781 (2015).
Koushik, S.V., Sundararaju, B., McGraw, R.A. & Phillips, R.S. Cloning, sequence and expression of kynureninase from Pseudomonas fluorescens. Arch. Biochem. Biophys. 344, 301–308 (1997).
Miroux, B. & Walker, J.E. Overproduction of proteins in Escherichia coli: mutant hosts that allow synthesis of some membrane proteins and globular proteins at high levels. J. Mol. Biol. 260, 289–298 (1996).
We are grateful to N. Ashoura for assistance with various aspects of this work, data interpretation and comments on the manuscript. This work was supported by funding from NIH 1 RO1 CA189623 (E. Stone and G.G.), the Cancer Prevention and Research Institute of Texas grant DP150061 (E. Stone, L.I.R.E. and G.G.) and Kyn Therapeutics (G.G. and E. Stone). Support from the American Cancer Society was provided to T.A.T. (Postdoctoral Fellowship 126584-PF-14-216-01-TBF), N.M. (Postdoctoral Fellowship 123506-PF-13-354-01-CDD) and J.B. (Postdoctoral Fellowship 128252-PF-15-143-01-CDD). M.D. acknowledges support by a postdoctoral fellowship from the Cancer Prevention and Research Institute of Texas (RP140108).
G.G. and E. Stone are inventors on intellectual property related to this work, and G.G., E. Stone, X.M.Z., K.M., S.C. and M.M. have equity interest in Kyn Therapeutics, a company pursuing the commercial development of this technology.
About this article
Cite this article
Triplett, T., Garrison, K., Marshall, N. et al. Reversal of indoleamine 2,3-dioxygenase–mediated cancer immune suppression by systemic kynurenine depletion with a therapeutic enzyme. Nat Biotechnol 36, 758–764 (2018). https://doi.org/10.1038/nbt.4180
Advanced Materials (2021)
Charge convertible biomimetic micellar nanoparticles for enhanced melanoma-targeted therapy through tumor cells and tumor-associated macrophages dual chemotherapy with IDO immunotherapy
Chemical Engineering Journal (2021)
Advanced Functional Materials (2021)
Reversing Immunosuppression in Hypoxic and Immune‐Cold Tumors with Ultrathin Oxygen Self‐Supplementing Polymer Nanosheets under Near Infrared Light Irradiation
Advanced Functional Materials (2021)
Current Opinion in Chemical Biology (2021)