Related Experiment Video
Updated: Dec 7, 2025
Intracellular Phosphoflow Cytometry of Acute Myeloid Leukemia Patient-Derived Xenotransplants
Published on: June 6, 2025
Role of indoleamine 2,3-dioxygenase in acute myeloid leukemia
Philip T Sobash1, Ravindra Kolhe2, Nagla Abdel Karim3
1Internal Medicine, White River Health System, Batesville, AR 72501, USA.
Abstract:
Indoleamine 2,3 dioxygenase (IDO), first discovered in the 1960s, is an enzyme that has become a highly investigated metabolic target in cancer research. IDO is the rate-limiting step in tryptophan metabolism catabolism into its byproducts - kynurenines. Both IDO and kynurenines have been implicated in altering the tumor microenvironment, allowing for a tolerogenesis by affecting T-cell maturation and proliferation, and more specifically by inducing differentiation into T regulatory cells. Two mechanisms have been suspected in creating this environment: tryptophan starvation and metabolite toxicity. IDO has been shown to be expressed not only in cancer cells but also in antigen-presenting cells. The exact mechanisms underlying the two different sites of expression have not been fully elucidated. To date, most literature has focused on the role of IDO in solid tumors; we provide a review of IDO and its impact on hematological malignancies - more specifically, acute myeloid leukemia. The pathophysiology of IDO will be discussed, including a summarization of the literature to date on how IDO expression effects prognosis and disease progression in acute myeloid leukemia, along with current IDO-specific therapeutics with future considerations.
Insights
Indoleamine 2,3 dioxygenase (IDO) impacts cancer by altering the tumor microenvironment. This review focuses on IDO
Area of Science:
- Biochemistry
- Immunology
- Oncology
Background:
- Indoleamine 2,3 dioxygenase (IDO) is a key enzyme in tryptophan metabolism, producing kynurenines.
- IDO and kynurenines influence the tumor microenvironment, promoting immune tolerance and affecting T-cell responses.
- IDO expression in cancer cells and antigen-presenting cells contributes to these effects through tryptophan depletion and metabolite toxicity.
Purpose of the Study:
- To review the role of IDO in hematological malignancies, specifically acute myeloid leukemia (AML).
- To discuss the pathophysiology of IDO in AML and its impact on disease progression.
- To summarize current IDO-targeted therapeutics and future directions for AML treatment.
Main Methods:
- Literature review of IDO's role in cancer, with a focus on hematological malignancies.
- Analysis of existing studies on IDO expression, pathophysiology, and therapeutic strategies in acute myeloid leukemia.
Main Results:
- IDO and kynurenines are implicated in immune evasion within the tumor microenvironment.
- IDO expression is linked to prognosis and disease progression in acute myeloid leukemia.
- Current therapeutic strategies targeting IDO are being investigated for AML.
Conclusions:
- IDO plays a significant role in the immune landscape of acute myeloid leukemia.
- Understanding IDO's mechanisms in AML is crucial for developing effective treatments.
- Targeting IDO presents a promising therapeutic avenue for acute myeloid leukemia patients.
