bims-mecami 2024-02-18 papers

Issue of 2024–02–18
six papers selected by
Oltea Sampetrean, Keio University

Int Immunol. 2024 Feb 14. pii: dxae007. [Epub ahead of print]

Reprogramming T cell metabolism to enhance adoptive cell therapies.

Adoptive cell therapy (ACT) is an immunotherapeutic approach that involves isolating T cells from a patient, culturing them ex vivo, then re-infusing the cells back into the patient. Although this strategy has shown remarkable efficacy in hematological malignancies, the solid-tumour microenvironment (TME) has presented serious challenges for therapy efficacy. Particularly, the TME has immunosuppressive signaling and presents a metabolically challenging environment that leads to T cell suppression. T cell metabolism is an expanding field of research with a focus on understanding its inherent link to T cell function. Here, we review the current model of T cell metabolism from naïve cells through effector and memory life stages, as well as updates to the model from recent literature. These models of metabolism have provided us with the tools and understanding to explore T cell metabolic and mitochondrial insufficiency in the TME. We discuss manipulations that can be made to these mitochondrial and metabolic pathways to enhance persistence of infused T cells, overcome the metabolically challenging TME and improve the efficacy of therapy in ACT models. Further understanding and investigation of the impact of metabolic pathways on T cell performance could contribute to improving therapy efficacy for patients.

Keywords: Cancer Immunology; Immunometabolism; Immunotherapy

DOI: https://doi.org/10.1093/intimm/dxae007

Front Immunol. 2024 ;15 1331641

The roles of epigallocatechin gallate in the tumor microenvironment, metabolic reprogramming, and immunotherapy.

Dongming Li, Donghui Cao, Yuanlin Sun, Yingnan Cui, Yangyu Zhang, Jing Jiang, Xueyuan Cao.

Cancer, a disease that modern medicine has not fully understood and conquered, with its high incidence and mortality, deprives countless patients of health and even life. According to global cancer statistics, there were an estimated 19.3 million new cancer cases and nearly 10 million cancer deaths in 2020, with the age-standardized incidence and mortality rates of 201.0 and 100.7 per 100,000, respectively. Although remarkable advancements have been made in therapeutic strategies recently, the overall prognosis of cancer patients remains not optimistic. Consequently, there are still many severe challenges to be faced and difficult problems to be solved in cancer therapy today. Epigallocatechin gallate (EGCG), a natural polyphenol extracted from tea leaves, has received much attention for its antitumor effects. Accumulating investigations have confirmed that EGCG can inhibit tumorigenesis and progression by triggering apoptosis, suppressing proliferation, invasion, and migration, altering tumor epigenetic modification, and overcoming chemotherapy resistance. Nevertheless, its regulatory roles and biomolecular mechanisms in the immune microenvironment, metabolic microenvironment, and immunotherapy remain obscure. In this article, we summarized the most recent updates about the effects of EGCG on tumor microenvironment (TME), metabolic reprogramming, and anti-cancer immunotherapy. The results demonstrated EGCG can promote the anti-cancer immune response of cytotoxic lymphocytes and dendritic cells (DCs), attenuate the immunosuppression of myeloid-derived suppressor cells (MDSCs) and regulatory T cells (Tregs), and inhibit the tumor-promoting functions of tumor-associated macrophages (TAMs), tumor-associated neutrophils (TANs), and various stromal cells including cancer-associated fibroblasts (CAFs), endothelial cells (ECs), stellate cells, and mesenchymal stem/stromal cells (MSCs). Additionally, EGCG can suppress multiple metabolic reprogramming pathways, including glucose uptake, aerobic glycolysis, glutamine metabolism, fatty acid anabolism, and nucleotide synthesis. Finally, EGCG, as an immunomodulator and immune checkpoint blockade, can enhance immunotherapeutic efficacy and may be a promising candidate for antitumor immunotherapy. In conclusion, EGCG plays versatile regulatory roles in TME and metabolic reprogramming, which provides novel insights and combined therapeutic strategies for cancer immunotherapy.

Keywords: antitumor immunity; epigallocatechin gallate; immunotherapy; metabolic reprogramming; tumor microenvironment

DOI: https://doi.org/10.3389/fimmu.2024.1331641

Cancer Immunol Immunother. 2024 Feb 13. 73(3): 52

Targeting metabolic sensing switch GPR84 on macrophages for cancer immunotherapy.

Jianying Li, Anjun Ma, Ruohan Zhang, Yao Chen, Chelsea Bolyard, Bao Zhao, Cankun Wang, Thera Pich, Wantong Li, Nuo Sun, Qin Ma, Haitao Wen, Steven K Clinton, William E Carson, Zihai Li, Gang Xin.

INTRODUCTION: As one of the major components of the tumor microenvironment, tumor-associated macrophages (TAMs) possess profound inhibitory activity against T cells and facilitate tumor escape from immune checkpoint blockade therapy. Converting this pro-tumorigenic toward the anti-tumorigenic phenotype thus is an important strategy for enhancing adaptive immunity against cancer. However, a plethora of mechanisms have been described for pro-tumorigenic differentiation in cancer, metabolic switches to program the anti-tumorigenic property of TAMs are elusive.
MATERIALS AND METHODS: From an unbiased analysis of single-cell transcriptome data from multiple tumor models, we discovered that anti-tumorigenic TAMs uniquely express elevated levels of a specific fatty acid receptor, G-protein-coupled receptor 84 (GPR84). Genetic ablation of GPR84 in mice leads to impaired pro-inflammatory polarization of macrophages, while enhancing their anti-inflammatory phenotype. By contrast, GPR84 activation by its agonist, 6-n-octylaminouracil (6-OAU), potentiates pro-inflammatory phenotype via the enhanced STAT1 pathway. Moreover, 6-OAU treatment significantly retards tumor growth and increases the anti-tumor efficacy of anti-PD-1 therapy.
CONCLUSION: Overall, we report a previously unappreciated fatty acid receptor, GPR84, that serves as an important metabolic sensing switch for orchestrating anti-tumorigenic macrophage polarization. Pharmacological agonists of GPR84 hold promise to reshape and reverse the immunosuppressive TME, and thereby restore responsiveness of cancer to overcome resistance to immune checkpoint blockade.

Keywords: Cancer immunotherapy; Immunometabolsim; Tumor-associated macrophage

DOI: https://doi.org/10.1007/s00262-023-03603-3

Cell Metab. 2024 Feb 08. pii: S1550-4131(24)00012-3. [Epub ahead of print]

Dietary elaidic acid boosts tumoral antigen presentation and cancer immunity via ACSL5.

Yongfeng Lai, Yuan Gao, Junhong Lin, Fangfang Liu, Liguo Yang, Jie Zhou, Ying Xue, Yan Li, Zhenzhen Chang, Jing Li, Tengfei Chao, Jing Chen, Xiang Cheng, Xianfu Gao, Xiong Li, Fujia Lu, Qian Chu, Weimin Wang.

Immunomodulatory effects of long-chain fatty acids (LCFAs) and their activating enzyme, acyl-coenzyme A (CoA) synthetase long-chain family (ACSL), in the tumor microenvironment remain largely unknown. Here, we find that ACSL5 functions as an immune-dependent tumor suppressor. ACSL5 expression sensitizes tumors to PD-1 blockade therapy in vivo and the cytotoxicity mediated by CD8+ T cells in vitro via regulation of major histocompatibility complex class I (MHC-I)-mediated antigen presentation. Through screening potential substrates for ACSL5, we further identify that elaidic acid (EA), a trans LCFA that has long been considered harmful to human health, phenocopies to enhance MHC-I expression. EA supplementation can suppress tumor growth and sensitize PD-1 blockade therapy. Clinically, ACSL5 expression is positively associated with improved survival in patients with lung cancer, and plasma EA level is also predictive for immunotherapy efficiency. Our findings provide a foundation for enhancing immunotherapy through either targeting ACSL5 or metabolic reprogramming of antigen presentation via dietary EA supplementation.

Keywords: ACSL5; CD8(+) T cell; MHC class I; NLRC5; antigen presentation; checkpoint blockade; elaidic acid; immunotherapy; long-chain fatty acids

DOI: https://doi.org/10.1016/j.cmet.2024.01.012

Oncol Res. 2024 ;32(3): 563-576

Glycogen metabolism-mediated intercellular communication in the tumor microenvironment influences liver cancer prognosis.

Yang Zhang, Nannan Qin, Xijun Wang, Rui Liang, Quan Liu, Ruoyi Geng, Tianxiao Jiang, Yunfei Liu, Jinwei Li.

Glycogen metabolism plays a key role in the development of hepatocellular carcinoma (HCC), but the function of glycogen metabolism genes in the tumor microenvironment (TME) is still to be elucidated. Single-cell RNA-seq data were obtained from ten HCC tumor samples totaling 64,545 cells, and 65 glycogen metabolism genes were analyzed by a nonnegative matrix factorization (NMF). The prognosis and immune response of new glycogen TME cell clusters were predicted by using HCC and immunotherapy cohorts from public databases. HCC single-cell analysis was divided into fibroblasts, NT T cells, macrophages, endothelial cells, and B cells, which were separately divided into new cell clusters by glycogen metabolism gene annotation. Pseudo-temporal trajectory analysis demonstrated the temporal differentiation trajectory of different glycogen subtype cell clusters. Cellular communication analysis revealed extensive interactions between endothelial cells with glycogen metabolizing TME cell-related subtypes and different glycogen subtype cell clusters. SCENIC analysis of transcription factors upstream of TME cell clusters with different glycogen metabolism. In addition, TME cell clusters of glycogen metabolism were found to be enriched in expression in CAF subtypes, CD8 depleted, M1, and M2 types. Bulk-seq analysis showed the prognostic significance of glycogen metabolism-mediated TME cell clusters in HCC, while a significant immune response was found in the immunotherapy cohort in patients treated with immune checkpoint blockade (ICB), especially for CAFs, T cells, and macrophages. In summary, our study reveals for the first time that glycogen metabolism mediates intercellular communication in the hepatocellular carcinoma microenvironment while elucidating the anti-tumor mechanisms and immune prognostic responses of different subtypes of cell clusters.

Keywords: Glycogen metabolism; Immunotherapy; Liver cancer; Metabolic map; Prognosis; Single-cell; Tumor microenvironment

DOI: https://doi.org/10.32604/or.2023.029697

Nat Cancer. 2024 Feb 14.

Efferocytosis reprograms the tumor microenvironment to promote pancreatic cancer liver metastasis.

Yuliana Astuti, Meirion Raymant, Valeria Quaranta, Kim Clarke, Maidinaimu Abudula, Olivia Smith, Gaia Bellomo, Vatshala Chandran-Gorner, Craig Nourse, Christopher Halloran, Paula Ghaneh, Daniel Palmer, Robert P Jones, Fiona Campbell, Jeffrey W Pollard, Jennifer P Morton, Ainhoa Mielgo, Michael C Schmid.

Pancreatic ductal adenocarcinoma is a highly metastatic disease and macrophages support liver metastases. Efferocytosis, or engulfment of apoptotic cells by macrophages, is an essential process in tissue homeostasis and wound healing, but its role in metastasis is less well understood. Here, we found that the colonization of the hepatic metastatic site is accompanied by low-grade tissue injury and that efferocytosis-mediated clearance of parenchymal dead cells promotes macrophage reprogramming and liver metastasis. Mechanistically, progranulin expression in macrophages is necessary for efficient efferocytosis by controlling lysosomal acidification via cystic fibrosis transmembrane conductance regulator and the degradation of lysosomal cargo, resulting in LXRα/RXRα-mediated macrophage conversion and upregulation of arginase 1. Pharmacological blockade of efferocytosis or macrophage-specific genetic depletion of progranulin impairs macrophage conversion, improves CD8+ T cell functions, and reduces liver metastasis. Our findings reveal how hard-wired functions of macrophages in tissue repair contribute to liver metastasis and identify potential targets for prevention of pancreatic ductal adenocarcinoma liver metastasis.

DOI: https://doi.org/10.1038/s43018-024-00731-2