Targeting PHGDH reverses the immunosuppressive phenotype of tumor-associated macrophages through α-ketoglutarate and mTORC1 signaling

Author(s)
Zhengnan Cai, Wan Li, Sonja Hager, Jayne Louise Wilson, Leila Afjehi-Sadat, Elke H. Heiss, Thomas Weichhart, Petra Heffeter, Wolfram Weckwerth
Abstract

Phosphoglycerate dehydrogenase (PHGDH) has emerged as a crucial factor in macromolecule synthesis, neutralizing oxidative stress, and regulating methylation reactions in cancer cells, lymphocytes, and endothelial cells. However, the role of PHGDH in tumor-associated macrophages (TAMs) is poorly understood. Here, we found that the T helper 2 (Th2) cytokine interleukin-4 and tumor-conditioned media upregulate the expression of PHGDH in macrophages and promote immunosuppressive M2 macrophage activation and proliferation. Loss of PHGDH disrupts cellular metabolism and mitochondrial respiration, which are essential for immunosuppressive macrophages. Mechanistically, PHGDH-mediated serine biosynthesis promotes α-ketoglutarate production, which activates mTORC1 signaling and contributes to the maintenance of an M2-like macrophage phenotype in the tumor microenvironment. Genetic ablation of PHGDH in macrophages from tumor-bearing mice results in attenuated tumor growth, reduced TAM infiltration, a phenotypic shift of M2-like TAMs toward an M1-like phenotype, downregulated PD-L1 expression and enhanced antitumor T-cell immunity. Our study provides a strong basis for further exploration of PHGDH as a potential target to counteract TAM-mediated immunosuppression and hinder tumor progression.

Organisation(s)
Research Platform Vienna Metabolomics Center, Department of Food Chemistry and Toxicology, Core Facility Shared Services UBB, Department of Pharmaceutical Sciences, Functional and Evolutionary Ecology
External organisation(s)
Medizinische Universität Wien, Vienna Doctoral School of Ecology and Evolution
Journal
Cellular and Molecular Immunology
Volume
21
Pages
448-465
No. of pages
18
ISSN
1672-7681
DOI
https://doi.org/10.1038/s41423-024-01134-0
Publication date
2024
Peer reviewed
Yes
Austrian Fields of Science 2012
301902 Immunology, 106052 Cell biology, 106023 Molecular biology, 301904 Cancer research
Keywords
ASJC Scopus subject areas
Immunology and Allergy, Immunology, Infectious Diseases
Sustainable Development Goals
SDG 3 - Good Health and Well-being
Portal url
https://ucrisportal.univie.ac.at/en/publications/targeting-phgdh-reverses-the-immunosuppressive-phenotype-of-tumorassociated-macrophages-through-ketoglutarate-and-mtorc1-signaling(7b506938-f803-40a3-8ba1-47c538f7d07c).html