Intra-tumoral hypoxia promotes CD8+ T cell dysfunction via chronic activation of integrated stress response transcription factor ATF4
- PMID: 41005293
- PMCID: PMC12666857
- DOI: 10.1016/j.immuni.2025.09.003
Intra-tumoral hypoxia promotes CD8+ T cell dysfunction via chronic activation of integrated stress response transcription factor ATF4
Abstract
Metabolic stress in the tumor microenvironment (TME) promotes T cell dysfunction and immune checkpoint inhibitor (ICI) resistance. We examined the contribution of activating transcription factor 4 (ATF4), the central node of the integrated stress response (ISR), to T cell dysfunction in tumors. CD8+ tumor-infiltrating lymphocytes (TILs) in patient samples exhibited chronic ATF4 activity, which was reflected across various tumor models. Hypoxia in the TME imposed chronic ATF4 activity via the ISR kinases. ATF4 overexpression in CD8+ T cells induced metabolic polarity, mitochondrial oxidative stress, and cell death, impairing antitumor immunity. Chronic ATF4 transcriptional activity replicated the terminal exhaustion CD8+ T cell state independent of T cell receptor (TCR) stimulation. Genetic or pharmacologic attenuation of ATF4 reduced mitochondrial oxidative stress and promoted CD8+ TIL viability, enabling response to programmed cell death protein-1 (PD-1) inhibitor therapy and conferring protection from re-emergent disease. Thus, the ISR converges on chronic ATF4 activity in CD8+ TILs as a barrier to ICI response, positioning ISR therapeutics as candidates for immunotherapy.
Keywords: ATF4; T cell; hypoxia; immunotherapy; integrated stress response; metabolism; mitochondria; tumor microenvironment.
Copyright © 2025 The Authors. Published by Elsevier Inc. All rights reserved.
Conflict of interest statement
Declaration of interests The authors declare no competing interests.
References
-
- Scharping NE, Rivadeneira DB, Menk AV, Vignali PDA, Ford BR, Rittenhouse NL, Peralta R, Wang Y, Wang Y, DePeaux K, et al. (2021). Mitochondrial stress induced by continuous stimulation under hypoxia rapidly drives T cell exhaustion. Nat Immunol 22, 205–215. 10.1038/s41590-020-00834-9. - DOI - PMC - PubMed
-
- Scharping NE, Menk AV, Moreci RS, Whetstone RD, Dadey RE, Watkins SC, Ferris RL, and Delgoffe GM (2016). The Tumor Microenvironment Represses T Cell Mitochondrial Biogenesis to Drive Intratumoral T Cell Metabolic Insufficiency and Dysfunction. Immunity 45, 374–388. 10.1016/j.immuni.2016.07.009. - DOI - PMC - PubMed
MeSH terms
Substances
Grants and funding
LinkOut - more resources
Full Text Sources
Medical
Molecular Biology Databases
Research Materials
