Carboxyamidotriazole combined with IDO1-Kyn-AhR pathway inhibitors profoundly enhances cancer immunotherapy

Bibliographic Details
Title: Carboxyamidotriazole combined with IDO1-Kyn-AhR pathway inhibitors profoundly enhances cancer immunotherapy
Authors: Jing Shi, Chen Chen, Rui Ju, Qingzhu Wang, Juan Li, Lei Guo, Caiying Ye, Dechang Zhang
Source: Journal for ImmunoTherapy of Cancer, Vol 7, Iss 1, Pp 1-14 (2019)
Publisher Information: BMJ Publishing Group, 2019.
Publication Year: 2019
Collection: LCC:Neoplasms. Tumors. Oncology. Including cancer and carcinogens
Subject Terms: CAI, PD-1, IFN-, IDO1, AhR, Neoplasms. Tumors. Oncology. Including cancer and carcinogens, RC254-282
More Details: Abstract Background Cancer immunotherapy has generated significant excitement, mainly as a result of the development of immune checkpoint inhibitors. The blockade of PD-1 or its ligand with antibodies has resulted in impressive clinical efficacy. However, a subset of patients does not respond to biologic therapeutics, and another subset suffers from severe immune-related adverse events in certain cases. The modulation of the immune system with small molecules might yield surprising benefits. Methods CD8+ cells were obtained through a magnetic cell sorting system (MACS), and their capabilities for IFN-γ release and PD-1 expression were analyzed. The in vitro effects of drugs were studied in a coculture system of tumor cells and activated CD8+ cells. We further isolated the primary tumor cells in tumor-bearing mice treated with CAI, DMF, 1-MT or a combination (CAI and DMF/CAI and 1-MT) and analyzed the percentages of CD8+ T cells and PD-1+CD8+ T cells among TILs. The selective anti-tumor immune reactions of the two drug combinations were confirmed in a coculture system consisting of B16-OVA cells and OVA-specific CTLs derived from OT-1 transgenic mice. The anti-tumor effects of the single drugs or combined therapies were assessed according to their capability to slow tumor growth and extend the life span of tumor-bearing mice, and they were compared with the effects of PD-1 antibody. Results CAI increased IFN-γ release from activated T cells, which might strengthen the anti-proliferative and anti-metastatic effects on cancer cells. However, CAI also stimulated IDO1-Kyn metabolic circuitry in the tumor microenvironment and facilitated tumor cell immune evasion. Combining CAI with 1-MT or DMF disrupted PD-1 expression and promoted IFN-γ production in CD8+ T cells, and it also increased T lymphocyte infiltration in the tumor microenvironment, inhibited tumor growth and prolonged the life spans of tumor-bearing mice. Conclusion Inhibitors of the IDO1-Kyn-AhR pathway could abolish the negative effects of CAI on CD8+ T cells and result in complementary and beneficial anti-tumor immune effects. The combination of CAI with 1-MT or DMF greatly augmented the ability of CD8+ T cells to kill malignant cells and showed a strong anti-cancer capability that was superior to that of either of the single agents was is comparable with that of anti-PD-1 antibody. The combinations of small molecules utilized in this study may serve as valuable new immunotherapy strategies for cancer treatment.
Document Type: article
File Description: electronic resource
Language: English
ISSN: 2051-1426
Relation: http://link.springer.com/article/10.1186/s40425-019-0725-7; https://doaj.org/toc/2051-1426
DOI: 10.1186/s40425-019-0725-7
Access URL: https://doaj.org/article/8493cecc3b124436abe311419c181770
Accession Number: edsdoj.8493cecc3b124436abe311419c181770
Database: Directory of Open Access Journals
More Details
ISSN:20511426
DOI:10.1186/s40425-019-0725-7
Published in:Journal for ImmunoTherapy of Cancer
Language:English