Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2025 Oct 14;58(10):2489-2504.e8.
doi: 10.1016/j.immuni.2025.09.003. Epub 2025 Sep 25.

Intra-tumoral hypoxia promotes CD8+ T cell dysfunction via chronic activation of integrated stress response transcription factor ATF4

Affiliations

Intra-tumoral hypoxia promotes CD8+ T cell dysfunction via chronic activation of integrated stress response transcription factor ATF4

Coral Del Mar Alicea Pauneto et al. Immunity. .

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.

PubMed Disclaimer

Conflict of interest statement

Declaration of interests The authors declare no competing interests.

References

    1. Siegel RL, Giaquinto AN, and Jemal A (2024). Cancer statistics, 2024. CA: A Cancer Journal for Clinicians 74, 12–49. 10.3322/caac.21820. - DOI - PubMed
    1. Wang Q, Shao X, Zhang Y, Zhu M, Wang FXC, Mu J, Li J, Yao H, and Chen K (2023). Role of tumor microenvironment in cancer progression and therapeutic strategy. Cancer Med 12, 11149–11165. 10.1002/cam4.5698. - DOI - PMC - PubMed
    1. Lim AR, Rathmell WK, and Rathmell JC (2020). The tumor microenvironment as a metabolic barrier to effector T cells and immunotherapy. Elife 9. 10.7554/eLife.55185. - DOI - PMC - PubMed
    1. 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
    1. 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

LinkOut - more resources