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Enhancing CAR-T cell efficacy in solid tumors by targeting the tumor microenvironment

Cellular & Molecular Immunology volume 18, pages 1085–1095 (2021)Cite this article

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Abstract

Chimeric antigen receptor (CAR)-T cell therapy has achieved successful outcomes against hematological malignancies and provided a new impetus for treating solid tumors. However, the efficacy of CAR-T cells for solid tumors remains unsatisfactory. The tumor microenvironment has an important role in interfering with and inhibiting the effector function of immune cells, among which upregulated inhibitory checkpoint receptors, soluble suppressive cytokines, altered chemokine expression profiles, aberrant vasculature, complicated stromal composition, hypoxia and abnormal tumor metabolism are major immunosuppressive mechanisms. In this review, we summarize the inhibitory factors that affect the function of CAR-T cells in tumor microenvironment and discuss approaches to improve CAR-T cell efficacy for solid tumor treatment by targeting those barriers.

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Acknowledgements

This work was supported by a grant from the National Natural Science Foundation of China (31821003 to X.L.) and Tsinghua-Peking Center for Life Sciences.

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Authors and Affiliations

  1. Department of Basic Medical Sciences and Institute for Immunology, Tsinghua University School of Medicine, Beijing, China

    Guangna Liu, Wei Rui, Xueqiang Zhao & Xin Lin

  2. China Immunotech (Beijing) Biotechnology Co.Ltd., Beijing, China

    Wei Rui & Xueqiang Zhao

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  1. Guangna Liu
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G.L. and X.L. conceptualized this review, G.L. wrote the manuscript, and W.R., X.Z., and X.L. edited and revised the manuscript. All authors approved the manuscript to be published.

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Correspondence to Xin Lin.

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Liu, G., Rui, W., Zhao, X. et al. Enhancing CAR-T cell efficacy in solid tumors by targeting the tumor microenvironment. Cell Mol Immunol 18, 1085–1095 (2021). https://doi.org/10.1038/s41423-021-00655-2

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