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Bergerud KMB, Berkseth M, Pardoll DM, Ganguly S, Kleinberg LR, Lawrence J, Odde DJ, Largaespada DA, Terezakis SA, Sloan L. Radiation Therapy and Myeloid-Derived Suppressor Cells: Breaking Down Their Cancerous Partnership. Int J Radiat Oncol Biol Phys 2024; 119:42-55. [PMID: 38042450 PMCID: PMC11082936 DOI: 10.1016/j.ijrobp.2023.11.050] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2023] [Revised: 11/18/2023] [Accepted: 11/22/2023] [Indexed: 12/04/2023]
Abstract
Radiation therapy (RT) has been a primary treatment modality in cancer for decades. Increasing evidence suggests that RT can induce an immunosuppressive shift via upregulation of cells such as tumor-associated macrophages (TAMs) and myeloid-derived suppressor cells (MDSCs). MDSCs inhibit antitumor immunity through potent immunosuppressive mechanisms and have the potential to be crucial tools for cancer prognosis and treatment. MDSCs interact with many different pathways, desensitizing tumor tissue and interacting with tumor cells to promote therapeutic resistance. Vascular damage induced by RT triggers an inflammatory signaling cascade and potentiates hypoxia in the tumor microenvironment (TME). RT can also drastically modify cytokine and chemokine signaling in the TME to promote the accumulation of MDSCs. RT activation of the cGAS-STING cytosolic DNA sensing pathway recruits MDSCs through a CCR2-mediated mechanism, inhibiting the production of type 1 interferons and hampering antitumor activity and immune surveillance in the TME. The upregulation of hypoxia-inducible factor-1 and vascular endothelial growth factor mobilizes MDSCs to the TME. After recruitment, MDSCs promote immunosuppression by releasing reactive oxygen species and upregulating nitric oxide production through inducible nitric oxide synthase expression to inhibit cytotoxic activity. Overexpression of arginase-1 on subsets of MDSCs degrades L-arginine and downregulates CD3ζ, inhibiting T-cell receptor reactivity. This review explains how radiation promotes tumor resistance through activation of immunosuppressive MDSCs in the TME and discusses current research targeting MDSCs, which could serve as a promising clinical treatment strategy in the future.
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Affiliation(s)
| | - Matthew Berkseth
- Department of Radiation Oncology, University of Minnesota, Minneapolis, Minnesota
| | - Drew M Pardoll
- Department of Oncology, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Sudipto Ganguly
- Department of Oncology, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Lawrence R Kleinberg
- Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Jessica Lawrence
- Department of Veterinary Clinical Sciences, University of Minnesota, St. Paul, Minnesota
| | - David J Odde
- Department of Biomedical Engineering, University of Minnesota, Minneapolis, Minnesota
| | - David A Largaespada
- Departments of Pediatrics and Genetics, Cell Biology, and Development, University of Minnesota, Minneapolis, Minnesota
| | | | - Lindsey Sloan
- Department of Radiation Oncology, University of Minnesota, Minneapolis, Minnesota.
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2
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Dias IHK, Shokr H. Oxysterols as Biomarkers of Aging and Disease. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2024; 1440:307-336. [PMID: 38036887 DOI: 10.1007/978-3-031-43883-7_16] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/02/2023]
Abstract
Oxysterols derive from either enzymatic or non-enzymatic oxidation of cholesterol. Even though they are produced as intermediates of bile acid synthesis pathway, they are recognised as bioactive compounds in cellular processes. Therefore, their absence or accumulation have been shown to be associated with disease phenotypes. This chapter discusses the contribution of oxysterol to ageing, age-related diseases such as neurodegeneration and various disorders such as cancer, cardiovascular disease, diabetes, metabolic and ocular disorders. It is clear that oxysterols play a significant role in development and progression of these diseases. As a result, oxysterols are being investigated as suitable markers for disease diagnosis purposes and some drug targets are in development targeting oxysterol pathways. However, further research will be needed to confirm the suitability of these potentials.
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Affiliation(s)
- Irundika H K Dias
- Aston Medical School, College of Health and Life Sciences, Aston University, Birmingham, UK.
| | - Hala Shokr
- Manchester Pharmacy School, Faculty of Biology, Medicine and Health, The University of Manchester, Manchester, UK
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3
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Jin J, Zhao Q, Wei Z, Chen K, Su Y, Hu X, Peng X. Glycolysis-cholesterol metabolic axis in immuno-oncology microenvironment: emerging role in immune cells and immunosuppressive signaling. Cell Biosci 2023; 13:189. [PMID: 37828561 PMCID: PMC10571292 DOI: 10.1186/s13578-023-01138-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2023] [Accepted: 09/21/2023] [Indexed: 10/14/2023] Open
Abstract
Cell proliferation and function require nutrients, energy, and biosynthesis activity to duplicate repertoires for each daughter. It is therefore not surprising that tumor microenvironment (TME) metabolic reprogramming primarily orchestrates the interaction between tumor and immune cells. Tumor metabolic reprogramming affords bioenergetic, signaling intermediates, and biosynthesis requirements for both malignant and immune cells. Different immune cell subsets are recruited into the TME, and these manifestations have distinct effects on tumor progression and therapeutic outcomes, especially the mutual contribution of glycolysis and cholesterol metabolism. In particularly, glycolysis-cholesterol metabolic axis interconnection plays a critical role in the TME modulation, and their changes in tumor metabolism appear to be a double-edged sword in regulating various immune cell responses and immunotherapy efficacy. Hence, we discussed the signature manifestation of the glycolysis-cholesterol metabolic axis and its pivotal role in tumor immune regulation. We also highlight how hypothetical combinations of immunotherapy and glycolysis/cholesterol-related metabolic interventions unleash the potential of anti-tumor immunotherapies, as well as developing more effective personalized treatment strategies.
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Affiliation(s)
- Jing Jin
- Department of Biotherapy, Cancer Center, West China Hospital, Sichuan University, Chengdu, People's Republic of China
- West China School of Medicine, Sichuan University, Chengdu, China
| | - Qijie Zhao
- Department of Pharmacy, West China Hospital, Sichuan University, Chengdu, Sichuan, People's Republic of China
| | - Zhigong Wei
- West China School of Medicine, Sichuan University, Chengdu, China
| | - Keliang Chen
- West China School of Medicine, Sichuan University, Chengdu, China
| | - Yonglin Su
- Department of Rehabilitation, Cancer Center, West China Hospital, Sichuan University, Sichuan, People's Republic of China.
| | - Xiaolin Hu
- Department of Nursing, West China Hospital, Sichuan University, Chengdu, People's Republic of China.
| | - Xingchen Peng
- Department of Biotherapy, Cancer Center, West China Hospital, Sichuan University, Chengdu, People's Republic of China.
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4
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Xiao M, Xu J, Wang W, Zhang B, Liu J, Li J, Xu H, Zhao Y, Yu X, Shi S. Functional significance of cholesterol metabolism in cancer: from threat to treatment. Exp Mol Med 2023; 55:1982-1995. [PMID: 37653037 PMCID: PMC10545798 DOI: 10.1038/s12276-023-01079-w] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2022] [Revised: 05/18/2023] [Accepted: 06/20/2023] [Indexed: 09/02/2023] Open
Abstract
Cholesterol is an essential structural component of membranes that contributes to membrane integrity and fluidity. Cholesterol homeostasis plays a critical role in the maintenance of cellular activities. Recently, increasing evidence has indicated that cholesterol is a major determinant by modulating cell signaling events governing the hallmarks of cancer. Numerous studies have shown the functional significance of cholesterol metabolism in tumorigenesis, cancer progression and metastasis through its regulatory effects on the immune response, ferroptosis, autophagy, cell stemness, and the DNA damage response. Here, we summarize recent literature describing cholesterol metabolism in cancer cells, including the cholesterol metabolism pathways and the mutual regulatory mechanisms involved in cancer progression and cholesterol metabolism. We also discuss various drugs targeting cholesterol metabolism to suggest new strategies for cancer treatment.
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Affiliation(s)
- Mingming Xiao
- Department of Pancreatic Surgery, Fudan University Shanghai Cancer Center, Shanghai, 200032, China
- Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, 200032, China
- Shanghai Pancreatic Center Institute, Shanghai, 200032, China
- Pancreatic Center Institute, Fudan University, Shanghai, 200032, China
| | - Jin Xu
- Department of Pancreatic Surgery, Fudan University Shanghai Cancer Center, Shanghai, 200032, China
- Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, 200032, China
- Shanghai Pancreatic Center Institute, Shanghai, 200032, China
- Pancreatic Center Institute, Fudan University, Shanghai, 200032, China
| | - Wei Wang
- Department of Pancreatic Surgery, Fudan University Shanghai Cancer Center, Shanghai, 200032, China
- Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, 200032, China
- Shanghai Pancreatic Center Institute, Shanghai, 200032, China
- Pancreatic Center Institute, Fudan University, Shanghai, 200032, China
| | - Bo Zhang
- Department of Pancreatic Surgery, Fudan University Shanghai Cancer Center, Shanghai, 200032, China
- Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, 200032, China
- Shanghai Pancreatic Center Institute, Shanghai, 200032, China
- Pancreatic Center Institute, Fudan University, Shanghai, 200032, China
| | - Jiang Liu
- Department of Pancreatic Surgery, Fudan University Shanghai Cancer Center, Shanghai, 200032, China
- Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, 200032, China
- Shanghai Pancreatic Center Institute, Shanghai, 200032, China
- Pancreatic Center Institute, Fudan University, Shanghai, 200032, China
| | - Jialin Li
- Department of Pancreatic Surgery, Fudan University Shanghai Cancer Center, Shanghai, 200032, China
- Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, 200032, China
- Shanghai Pancreatic Center Institute, Shanghai, 200032, China
- Pancreatic Center Institute, Fudan University, Shanghai, 200032, China
| | - Hang Xu
- Department of Pancreatic Surgery, Fudan University Shanghai Cancer Center, Shanghai, 200032, China
- Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, 200032, China
- Shanghai Pancreatic Center Institute, Shanghai, 200032, China
- Pancreatic Center Institute, Fudan University, Shanghai, 200032, China
| | - Yingjun Zhao
- Institutes of Biomedical Sciences, Shanghai Medical College, Fudan University, Shanghai, 200032, China
| | - Xianjun Yu
- Department of Pancreatic Surgery, Fudan University Shanghai Cancer Center, Shanghai, 200032, China.
- Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, 200032, China.
- Shanghai Pancreatic Center Institute, Shanghai, 200032, China.
- Pancreatic Center Institute, Fudan University, Shanghai, 200032, China.
| | - Si Shi
- Department of Pancreatic Surgery, Fudan University Shanghai Cancer Center, Shanghai, 200032, China.
- Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, 200032, China.
- Shanghai Pancreatic Center Institute, Shanghai, 200032, China.
- Pancreatic Center Institute, Fudan University, Shanghai, 200032, China.
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5
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Chen Y, Xu Y, Zhao H, Zhou Y, Zhang J, Lei J, Wu L, Zhou M, Wang J, Yang S, Zhang X, Yan G, Li Y. Myeloid-derived suppressor cells deficient in cholesterol biosynthesis promote tumor immune evasion. Cancer Lett 2023; 564:216208. [PMID: 37150500 DOI: 10.1016/j.canlet.2023.216208] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2023] [Revised: 04/27/2023] [Accepted: 04/28/2023] [Indexed: 05/09/2023]
Abstract
Cancer immunotherapy targeting myeloid-derived suppressor cells (MDSCs) is one of the most promising anticancer strategies. Metabolic reprogramming is vital for MDSC activation, however, the regulatory mechanisms of cholesterol metabolic reprogramming in MDSCs remains largely unexplored. Using the receptor-interacting protein kinase 3 (RIPK3)-deficient MDSC model, a previously established tumor-infiltrating MDSC-like model, we found that the cholesterol accumulation was significantly decreased in these cells. Moreover, the phosphorylated AKT-mTORC1 signaling was reduced, and downstream SREBP2-HMGCR-mediated cholesterol synthesis was blunted. Interestingly, cholesterol deficiency profoundly elevated the immunosuppressive activity of MDSCs. Mechanistically, cholesterol elimination induced nuclear accumulation of LXRβ, thereby promoting LXRβ-RXRα heterodimer binding of a novel composite element in the promoter of Arg1. Furthermore, itraconazole enhanced the immunosuppressive activity of MDSCs to boost tumor growth by suppressing the RIPK3-AKT-mTORC1 pathway and impeding cholesterol synthesis. Our findings demonstrate that RIPK3 deficiency leads to cholesterol abrogation in MDSCs, which facilitates tumor-infiltrating MDSC activation, and highlight the therapeutic potential of targeting cholesterol synthesis to overcome tumor immune evasion.
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Affiliation(s)
- Yu Chen
- Department of Medical Oncology, Chongqing University Cancer Hospital, Chongqing, 400030, China
| | - Yanquan Xu
- Clinical Medicine Research Center, Xinqiao Hospital, Army Medical University, Chongqing, 400037, China
| | - Huakan Zhao
- Department of Medical Oncology, Chongqing University Cancer Hospital, Chongqing, 400030, China
| | - Yu Zhou
- Department of Medical Oncology, Chongqing University Cancer Hospital, Chongqing, 400030, China
| | - Jiangang Zhang
- Department of Medical Oncology, Chongqing University Cancer Hospital, Chongqing, 400030, China
| | - Juan Lei
- Department of Medical Oncology, Chongqing University Cancer Hospital, Chongqing, 400030, China
| | - Lei Wu
- Department of Medical Oncology, Chongqing University Cancer Hospital, Chongqing, 400030, China
| | - Mingyue Zhou
- Department of Medical Oncology, Chongqing University Cancer Hospital, Chongqing, 400030, China
| | - Jingchun Wang
- Department of Gastroenterology, Xinqiao Hospital, Army Medical University, Chongqing, 400037, China
| | - Shuai Yang
- Department of Pathology, The 958th Hospital, Southwest Hospital, Third Military Medical University, Chongqing, 400037, China
| | - Xiao Zhang
- Army 953 Hospital, Shigatse Branch of Xinqiao Hospital, Army Medical University, Shigatse, Tibet Autonomous Region, 857000, China
| | - Guifang Yan
- Department of Medical Oncology, Chongqing University Cancer Hospital, Chongqing, 400030, China.
| | - Yongsheng Li
- Department of Medical Oncology, Chongqing University Cancer Hospital, Chongqing, 400030, China; Clinical Medicine Research Center, Xinqiao Hospital, Army Medical University, Chongqing, 400037, China.
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6
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Zhang W, Fang X, Gao C, Song C, He Y, Zhou T, Yang X, Shang Y, Xu J. MDSCs in sepsis-induced immunosuppression and its potential therapeutic targets. Cytokine Growth Factor Rev 2023; 69:90-103. [PMID: 35927154 DOI: 10.1016/j.cytogfr.2022.07.007] [Citation(s) in RCA: 22] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2022] [Revised: 07/18/2022] [Accepted: 07/19/2022] [Indexed: 02/07/2023]
Abstract
Sepsis is a life-threatening organ dysfunction caused by a dysregulated host response to infection. In sepsis, a complicated immune response is initiated, which varies over time with sustained excessive inflammation and immunosuppression. Identifying a promising way to orchestrate sepsis-induced immunosuppression is a challenge. Myeloid-derived suppressor cells (MDSCs) comprise pathologically activated neutrophils and monocytes with potent immunosuppressive activity. They play an important part in inhibiting innate and adaptive immune responses, and have emerged as part of the immune response in sepsis. MDSCs numbers are persistently high in sepsis patients, and associated with nosocomial infections and other adverse clinical outcomes. However, their characteristics and functional mechanisms during sepsis have not been addressed fully. Our review sheds light on the features and suppressive mechanism of MDSCs. We also review the potential applications of MDSCs as biomarkers and targets for clinical treatment of sepsis.
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Affiliation(s)
- Wanying Zhang
- Department of Critical Care Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China; Institute of Anesthesiology and critical care Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
| | - Xiangzhi Fang
- Department of Critical Care Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Chenggang Gao
- Department of Critical Care Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Chaoying Song
- Department of Critical Care Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Yajun He
- Department of Critical Care Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Ting Zhou
- Department of Critical Care Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Xiaobo Yang
- Department of Critical Care Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - You Shang
- Department of Critical Care Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China; Institute of Anesthesiology and critical care Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China.
| | - Jiqian Xu
- Department of Critical Care Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China; Institute of Anesthesiology and critical care Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China.
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7
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van Geffen C, Heiss C, Deißler A, Kolahian S. Pharmacological modulation of myeloid-derived suppressor cells to dampen inflammation. Front Immunol 2022; 13:933847. [PMID: 36110844 PMCID: PMC9468781 DOI: 10.3389/fimmu.2022.933847] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2022] [Accepted: 07/26/2022] [Indexed: 11/13/2022] Open
Abstract
Myeloid-derived suppressor cells (MDSCs) are a heterogeneous cell population with potent suppressive and regulative properties. MDSCs’ strong immunosuppressive potential creates new possibilities to treat chronic inflammation and autoimmune diseases or induce tolerance towards transplantation. Here, we summarize and critically discuss different pharmacological approaches which modulate the generation, activation, and recruitment of MDSCs in vitro and in vivo, and their potential role in future immunosuppressive therapy.
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8
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Metabolic reprograming of MDSCs within tumor microenvironment and targeting for cancer immunotherapy. Acta Pharmacol Sin 2022; 43:1337-1348. [PMID: 34561553 PMCID: PMC9160034 DOI: 10.1038/s41401-021-00776-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2021] [Accepted: 09/07/2021] [Indexed: 02/07/2023] Open
Abstract
A number of emerging studies in field of immune metabolism have indicated that cellular metabolic reprograming serves as a major administrator in maintaining the viability and functions of both tumor cells and immune cells. As one of the most important immunosuppressive cells in tumor stroma, myeloid-derived suppressor cells (MDSCs) dynamically orchestrate their metabolic pathways in response to the complicated tumor microenvironment (TME), a process that consequently limits the therapeutic effectiveness of anti-cancer treatment modalities. In this context, the metabolic vulnerabilities of MDSCs could be exploited as a novel immune metabolic checkpoint upon which to intervene for promoting the efficacy of immunotherapy. Here, we have discussed about recent studies highlighting the important roles of the metabolic reprograming and the core molecular pathways involved in tumor-infiltrating MDSCs. In addition, we have also summarized the state-of-the-art strategies that are currently being employed to target MDSC metabolism and improve the efficacy of antineoplastic immunotherapy.
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9
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Targeting Nuclear Receptors in Lung Cancer—Novel Therapeutic Prospects. Pharmaceuticals (Basel) 2022; 15:ph15050624. [PMID: 35631448 PMCID: PMC9145966 DOI: 10.3390/ph15050624] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2022] [Revised: 05/10/2022] [Accepted: 05/13/2022] [Indexed: 01/27/2023] Open
Abstract
Lung cancer, the second most commonly diagnosed cancer, is the major cause of fatalities worldwide for both men and women, with an estimated 2.2 million new incidences and 1.8 million deaths, according to GLOBOCAN 2020. Although various risk factors for lung cancer pathogenesis have been reported, controlling smoking alone has a significant value as a preventive measure. In spite of decades of extensive research, mechanistic cues and targets need to be profoundly explored to develop potential diagnostics, treatments, and reliable therapies for this disease. Nuclear receptors (NRs) function as transcription factors that control diverse biological processes such as cell growth, differentiation, development, and metabolism. The aberrant expression of NRs has been involved in a variety of disorders, including cancer. Deregulation of distinct NRs in lung cancer has been associated with numerous events, including mutations, epigenetic modifications, and different signaling cascades. Substantial efforts have been made to develop several small molecules as agonists or antagonists directed to target specific NRs for inhibiting tumor cell growth, migration, and invasion and inducing apoptosis in lung cancer, which makes NRs promising candidates for reliable lung cancer therapeutics. The current work focuses on the importance of various NRs in the development and progression of lung cancer and highlights the different small molecules (e.g., agonist or antagonist) that influence NR expression, with the goal of establishing them as viable therapeutics to combat lung cancer.
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10
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Xue A, Shang Y, Jiao P, Zhang S, Zhu C, He X, Feng G, Fan S. Increased activation of
cGAS‐STING
pathway enhances radiosensitivity of non‐small cell lung cancer cells. Thorac Cancer 2022; 13:1361-1368. [PMID: 35429143 PMCID: PMC9058302 DOI: 10.1111/1759-7714.14400] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2022] [Revised: 03/09/2022] [Accepted: 03/11/2022] [Indexed: 12/25/2022] Open
Abstract
Background Methods Results Conclusion
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Affiliation(s)
- Aiying Xue
- Tianjin Key Laboratory of Radiation Medicine and Molecular Nuclear Medicine, Institute of Radiation Medicine Chinese Academy of Medical Sciences and Peking Union Medical College Tianjin China
| | - Yue Shang
- Tianjin Key Laboratory of Radiation Medicine and Molecular Nuclear Medicine, Institute of Radiation Medicine Chinese Academy of Medical Sciences and Peking Union Medical College Tianjin China
| | - Peng Jiao
- Department of Thoracic Surgery, Beijing Hospital, National Center of Gerontology, Institute of Geriatric Medicine Chinese Academy of Medical Sciences Beijing China
| | - Songling Zhang
- Tianjin Key Laboratory of Radiation Medicine and Molecular Nuclear Medicine, Institute of Radiation Medicine Chinese Academy of Medical Sciences and Peking Union Medical College Tianjin China
| | - Changchun Zhu
- Tianjin Key Laboratory of Radiation Medicine and Molecular Nuclear Medicine, Institute of Radiation Medicine Chinese Academy of Medical Sciences and Peking Union Medical College Tianjin China
| | - Xin He
- Tianjin Key Laboratory of Radiation Medicine and Molecular Nuclear Medicine, Institute of Radiation Medicine Chinese Academy of Medical Sciences and Peking Union Medical College Tianjin China
| | - Guoxing Feng
- Tianjin Key Laboratory of Radiation Medicine and Molecular Nuclear Medicine, Institute of Radiation Medicine Chinese Academy of Medical Sciences and Peking Union Medical College Tianjin China
| | - Saijun Fan
- Tianjin Key Laboratory of Radiation Medicine and Molecular Nuclear Medicine, Institute of Radiation Medicine Chinese Academy of Medical Sciences and Peking Union Medical College Tianjin China
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11
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Jiménez-Cortegana C, Galassi C, Klapp V, Gabrilovich DI, Galluzzi L. Myeloid-Derived Suppressor Cells and Radiotherapy. Cancer Immunol Res 2022; 10:545-557. [DOI: 10.1158/2326-6066.cir-21-1105] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2021] [Revised: 01/21/2022] [Accepted: 02/22/2022] [Indexed: 11/16/2022]
Abstract
Abstract
Myeloid-derived suppressor cells (MDSC) are a heterogeneous population of pathologically activated, mostly immature, myeloid cells that exert robust immunosuppressive functions. MDSCs expand during oncogenesis and have been linked to accelerated disease progression and resistance to treatment in both preclinical tumor models and patients with cancer. Thus, MDSCs stand out as promising targets for the development of novel immunotherapeutic regimens with superior efficacy. Here, we summarize accumulating preclinical and clinical evidence indicating that MDSCs also hamper the efficacy of radiotherapy (RT), as we critically discuss the potential of MDSC-targeting strategies as tools to achieve superior immunotherapeutic tumor control by RT in the clinic.
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Affiliation(s)
- Carlos Jiménez-Cortegana
- Department of Radiation Oncology, Weill Cornell Medical College, New York, New York
- Department of Medical Biochemistry, Molecular Biology and Immunology, Faculty of Medicine, University of Seville, Seville, Spain
| | - Claudia Galassi
- Department of Radiation Oncology, Weill Cornell Medical College, New York, New York
| | - Vanessa Klapp
- Department of Radiation Oncology, Weill Cornell Medical College, New York, New York
| | | | - Lorenzo Galluzzi
- Department of Radiation Oncology, Weill Cornell Medical College, New York, New York
- Sandra and Edward Meyer Cancer Center, New York, New York
- Caryl and Israel Englander Institute for Precision Medicine, New York, New York
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12
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Ling Z, Yang C, Tan J, Dou C, Chen Y. Beyond immunosuppressive effects: dual roles of myeloid-derived suppressor cells in bone-related diseases. Cell Mol Life Sci 2021; 78:7161-7183. [PMID: 34635950 PMCID: PMC11072300 DOI: 10.1007/s00018-021-03966-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2021] [Revised: 09/11/2021] [Accepted: 09/29/2021] [Indexed: 02/08/2023]
Abstract
Myeloid-derived suppressor cells (MDSCs) are a heterogeneous population of immature myeloid cells (IMCs) with immunosuppressive functions, whereas IMCs originally differentiate into granulocytes, macrophages, and dendritic cells (DCs) to participate in innate immunity under steady-state conditions. At present, difficulties remain in identifying MDSCs due to lacking of specific biomarkers. To make identification of MDSCs accurately, it also needs to be determined whether having immunosuppressive functions. MDSCs play crucial roles in anti-tumor, angiogenesis, and metastasis. Meanwhile, MDSCs could make close interaction with osteoclasts, osteoblasts, chondrocytes, and other stromal cells within microenvironment of bone and joint, and thereby contributing to poor prognosis of bone-related diseases such as cancer-related bone metastasis, osteosarcoma (OS), rheumatoid arthritis (RA), osteoarthritis (OA), and orthopedic trauma. In addition, MDSCs have been shown to participate in the procedure of bone repair. In this review, we have summarized the function of MDSCs in cancer-related bone metastasis, the interaction with stromal cells within the bone microenvironment as well as joint microenvironment, and the critical role of MDSCs in bone repair. Besides, the promising value of MDSCs in the treatment for bone-related diseases is also well discussed.
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Affiliation(s)
- Zhiguo Ling
- Department of Orthopaedics, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, 400038, China
| | - Chuan Yang
- Department of Biomedical Materials Science, Third Military Medical University (Army Medical University), Chongqing, 400038, China
| | - Jiulin Tan
- Department of Orthopaedics, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, 400038, China
| | - Ce Dou
- Department of Orthopaedics, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, 400038, China
| | - Yueqi Chen
- Department of Orthopaedics, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, 400038, China.
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13
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Li Y, He H, Jihu R, Zhou J, Zeng R, Yan H. Novel Characterization of Myeloid-Derived Suppressor Cells in Tumor Microenvironment. Front Cell Dev Biol 2021; 9:698532. [PMID: 34527668 PMCID: PMC8435631 DOI: 10.3389/fcell.2021.698532] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2021] [Accepted: 08/09/2021] [Indexed: 11/21/2022] Open
Abstract
Myeloid-derived suppressor cells (MDSCs) are a heterogeneous group of cells generated in various pathologic conditions, which have been known to be key components of the tumor microenvironment (TME) involving in tumor immune tolerance. So MDSCs have been extensively researched recently. As its name suggests, immunosuppression is the widely accepted function of MDSCs. Aside from suppressing antitumor immune responses, MDSCs in the TME also stimulate tumor angiogenesis and metastasis, thereby promoting tumor growth and development. Therefore, altering the recruitment, expansion, activation, and immunosuppression of MDSCs could partially restore antitumor immunity. So, this view focused on the favorable TME conditions that promote the immunosuppressive effects of MDSCs and contribute to targeted therapies with increased precision for MDSCs.
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Affiliation(s)
- Yanan Li
- Immunotherapy Laboratory, College of Pharmacology, Southwest Minzu University, Chengdu, China
| | - Hongdan He
- Immunotherapy Laboratory, Qinghai Tibet Plateau Research Institute, Southwest Minzu University, Chengdu, China
| | - Ribu Jihu
- Immunotherapy Laboratory, College of Pharmacology, Southwest Minzu University, Chengdu, China
| | - Junfu Zhou
- Immunotherapy Laboratory, College of Pharmacology, Southwest Minzu University, Chengdu, China
| | - Rui Zeng
- Immunotherapy Laboratory, College of Pharmacology, Southwest Minzu University, Chengdu, China
| | - Hengxiu Yan
- Immunotherapy Laboratory, College of Pharmacology, Southwest Minzu University, Chengdu, China
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14
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Li X, Li Y, Yu Q, Qian P, Huang H, Lin Y. Metabolic reprogramming of myeloid-derived suppressor cells: An innovative approach confronting challenges. J Leukoc Biol 2021; 110:257-270. [PMID: 34075637 PMCID: PMC8361984 DOI: 10.1002/jlb.1mr0421-597rr] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2020] [Revised: 04/11/2021] [Accepted: 04/12/2021] [Indexed: 02/06/2023] Open
Abstract
Immune cells such as T cells, macrophages, dendritic cells, and other immunoregulatory cells undergo metabolic reprogramming in cancer and inflammation-derived microenvironment to meet specific physiologic and functional demands. Myeloid-derived suppressor cells (MDSCs) are a heterogeneous population of immature myeloid cells that are characterized by immunosuppressive activity, which plays a key role in host immune homeostasis. In this review, we have discussed the core metabolic pathways, including glycolysis, lipid and fatty acid biosynthesis, and amino acid metabolism in the MDSCs under various pathologic situations. Metabolic reprogramming is a determinant of the phenotype and functions of MDSCs, and is therefore a novel therapeutic possibility in various diseases.
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Affiliation(s)
- Xiaoqing Li
- Bone Marrow Transplantation Center, the First Affiliated Hospital, School of MedicineZhejiang UniversityHangzhouZhejiangChina
- Institute of HematologyZhejiang UniversityHangzhouZhejiangChina
- Zhejiang Province Engineering Laboratory for Stem Cell and Immunity TherapyHangzhouZhejiangChina
- Liangzhu LaboratoryZhejiang University Medical CenterHangzhouZhejiangChina
| | - Yixue Li
- Bone Marrow Transplantation Center, the First Affiliated Hospital, School of MedicineZhejiang UniversityHangzhouZhejiangChina
- Institute of HematologyZhejiang UniversityHangzhouZhejiangChina
- Zhejiang Province Engineering Laboratory for Stem Cell and Immunity TherapyHangzhouZhejiangChina
- Liangzhu LaboratoryZhejiang University Medical CenterHangzhouZhejiangChina
| | - Qinru Yu
- Bone Marrow Transplantation Center, the First Affiliated Hospital, School of MedicineZhejiang UniversityHangzhouZhejiangChina
- Institute of HematologyZhejiang UniversityHangzhouZhejiangChina
- Zhejiang Province Engineering Laboratory for Stem Cell and Immunity TherapyHangzhouZhejiangChina
- Liangzhu LaboratoryZhejiang University Medical CenterHangzhouZhejiangChina
| | - Pengxu Qian
- Institute of HematologyZhejiang UniversityHangzhouZhejiangChina
- Zhejiang Province Engineering Laboratory for Stem Cell and Immunity TherapyHangzhouZhejiangChina
- Liangzhu LaboratoryZhejiang University Medical CenterHangzhouZhejiangChina
| | - He Huang
- Bone Marrow Transplantation Center, the First Affiliated Hospital, School of MedicineZhejiang UniversityHangzhouZhejiangChina
- Institute of HematologyZhejiang UniversityHangzhouZhejiangChina
- Zhejiang Province Engineering Laboratory for Stem Cell and Immunity TherapyHangzhouZhejiangChina
- Liangzhu LaboratoryZhejiang University Medical CenterHangzhouZhejiangChina
| | - Yu Lin
- Bone Marrow Transplantation Center, the First Affiliated Hospital, School of MedicineZhejiang UniversityHangzhouZhejiangChina
- Institute of HematologyZhejiang UniversityHangzhouZhejiangChina
- Zhejiang Province Engineering Laboratory for Stem Cell and Immunity TherapyHangzhouZhejiangChina
- Liangzhu LaboratoryZhejiang University Medical CenterHangzhouZhejiangChina
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15
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Wang Q, Wang J, Wang J, Zhang H. Molecular mechanism of liver X receptors in cancer therapeutics. Life Sci 2021; 273:119287. [PMID: 33667512 DOI: 10.1016/j.lfs.2021.119287] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Revised: 02/16/2021] [Accepted: 02/23/2021] [Indexed: 02/08/2023]
Abstract
Liver X receptors (LXRs) are receptors that belong to the nuclear receptor superfamily (NRs). It was originally called the "orphan receptor" when it was firstly discovered. Then it was found to be activated by oxysterol and it was officially named LXRs. LXRs are activated by ligands and bind to the retinol X receptor to form a heterodimer and regulate metabolism. Numerous studies have shown that LXRs are involved in regulating immune function and maintaining immune tolerance. Activating LXRs can also inhibit the tumorigenesis and promote apoptosis of tumor cells, which make LXRs as potential targets in cancer treatment. This review will discuss the recent progress of LXRs from the structure and function of LXRs, the signaling pathway of LXRs, the molecular mechanism of LXRs activation in cancers, and the potential targets of LXRs in cancer therapy.
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Affiliation(s)
- Qiang Wang
- Institute of Life Sciences, Jiangsu University, Zhenjiang, Jiangsu, China
| | - Jing Wang
- Institute of Life Sciences, Jiangsu University, Zhenjiang, Jiangsu, China
| | - Jiayou Wang
- Institute of Life Sciences, Jiangsu University, Zhenjiang, Jiangsu, China
| | - Heng Zhang
- Department of General Surgery, Nanjing Lishui District People's Hospital, Zhongda Hospital Lishui Branch, Southeast University, Nanjing, China.
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16
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Goel D, Vohora D. Liver X receptors and skeleton: Current state-of-knowledge. Bone 2021; 144:115807. [PMID: 33333244 DOI: 10.1016/j.bone.2020.115807] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/25/2020] [Revised: 11/26/2020] [Accepted: 12/11/2020] [Indexed: 12/25/2022]
Abstract
The liver X receptors (LXR) is a nuclear receptor that acts as a prominent regulator of lipid homeostasis and inflammatory response. Its therapeutic effectiveness against various diseases like Alzheimer's disease and atherosclerosis has been investigated in detail. Emerging pieces of evidence now reveal that LXR is also a crucial modulator of bone remodeling. However, the molecular mechanisms underlying the pharmacological actions of LXR on the skeleton and its role in osteoporosis are poorly understood. Therefore, in the current review, we highlight LXR and its actions through different molecular pathways modulating skeletal homeostasis. The studies described in this review propound that LXR in association with estrogen, PTH, PPARγ, RXR hedgehog, and canonical Wnt signaling regulates osteoclastogenesis and bone resorption. It regulates RANKL-induced expression of c-Fos, NFATc1, and NF-κB involved in osteoclast differentiation. Additionally, several studies suggest suppression of RANKL-induced osteoclast differentiation by synthetic LXR ligands. Given the significance of modulation of LXR in various physiological and pathological settings, our findings indicate that therapeutic targeting of LXR might potentially prevent or treat osteoporosis and improve bone quality.
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Affiliation(s)
- Divya Goel
- Department of Pharmacology, School of Pharmaceutical Education and Research (SPER), Jamia Hamdard, New Delhi 110062, India
| | - Divya Vohora
- Department of Pharmacology, School of Pharmaceutical Education and Research (SPER), Jamia Hamdard, New Delhi 110062, India.
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17
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Bilotta MT, Petillo S, Santoni A, Cippitelli M. Liver X Receptors: Regulators of Cholesterol Metabolism, Inflammation, Autoimmunity, and Cancer. Front Immunol 2020; 11:584303. [PMID: 33224146 PMCID: PMC7670053 DOI: 10.3389/fimmu.2020.584303] [Citation(s) in RCA: 66] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2020] [Accepted: 10/12/2020] [Indexed: 12/31/2022] Open
Abstract
The interplay between cellular stress and immune response can be variable and sometimes contradictory. The mechanisms by which stress-activated pathways regulate the inflammatory response to a pathogen, in autoimmunity or during cancer progression remain unclear in many aspects, despite our recent knowledge of the signalling and transcriptional pathways involved in these diseases. In this context, over the last decade many studies demonstrated that cholesterol metabolism is an important checkpoint for immune homeostasis and cancer progression. Indeed, cholesterol is actively metabolized and can regulate, through its mobilization and/or production of active derivatives, many aspects of immunity and inflammation. Moreover, accumulation of cholesterol has been described in cancer cells, indicating metabolic addiction. The nuclear receptors liver-X-receptors (LXRs) are important regulators of intracellular cholesterol and lipids homeostasis. They have also key regulatory roles in immune response, as they can regulate inflammation, innate and adaptive immunity. Moreover, activation of LXRs has been reported to affect the proliferation and survival of different cancer cell types that show altered metabolic pathways and accumulation of cholesterol. In this minireview we will give an overview of the recent understandings about the mechanisms through which LXRs regulate inflammation, autoimmunity, and cancer, and the therapeutic potential for future treatment of these diseases through modulation of cholesterol metabolism.
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Affiliation(s)
| | - Sara Petillo
- Department of Molecular Medicine, Sapienza University of Rome, Rome, Italy
| | - Angela Santoni
- Department of Molecular Medicine, Sapienza University of Rome, Rome, Italy
- Istituto Pasteur-Fondazione Cenci Bolognetti, Rome, Italy
- Istituto Mediterraneo di Neuroscienze Neuromed, Pozzilli, Italy
| | - Marco Cippitelli
- Department of Molecular Medicine, Sapienza University of Rome, Rome, Italy
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18
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Kloudova-Spalenkova A, Holy P, Soucek P. Oxysterols in cancer management: From therapy to biomarkers. Br J Pharmacol 2020; 178:3235-3247. [PMID: 32986851 DOI: 10.1111/bph.15273] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2020] [Revised: 09/03/2020] [Accepted: 09/11/2020] [Indexed: 12/20/2022] Open
Abstract
Oxysterols are oxidized derivatives of cholesterol, both endogenous and exogenous. They have been implicated in numerous pathologies, including cancer. In addition to their roles in carcinogenesis, proliferation, migration, apoptosis, and multiple signalling pathways, they have been shown to modulate cancer therapy. They are known to affect therapy of hormonally positive breast cancer through modulating oestrogen receptor activity. Oxysterols have also been shown in various in vitro models to influence efficacy of chemotherapeutics, such as doxorubicin, vincristine, cisplatin, 5-fluorouracil, and others. Their effects on the immune system should also be considered in immunotherapy. Selective anti-cancer cytotoxic properties of some oxysterols make them candidates for new therapeutic molecules. Finally, differences in oxysterol levels in blood of cancer patients in different stages or versus healthy controls, and in tumour versus non-tumour tissues, show potential of oxysterols as biomarkers for cancer management and patient stratification for optimization of therapy. LINKED ARTICLES: This article is part of a themed issue on Oxysterols, Lifelong Health and Therapeutics. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v178.16/issuetoc.
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Affiliation(s)
- Alzbeta Kloudova-Spalenkova
- Department of Toxicogenomics, National Institute of Public Health, Prague, Czech Republic.,Third Faculty of Medicine, Charles University, Prague, Czech Republic.,Biomedical Center, Faculty of Medicine in Pilsen, Charles University, Pilsen, Czech Republic
| | - Petr Holy
- Department of Toxicogenomics, National Institute of Public Health, Prague, Czech Republic.,Third Faculty of Medicine, Charles University, Prague, Czech Republic.,Biomedical Center, Faculty of Medicine in Pilsen, Charles University, Pilsen, Czech Republic
| | - Pavel Soucek
- Department of Toxicogenomics, National Institute of Public Health, Prague, Czech Republic.,Biomedical Center, Faculty of Medicine in Pilsen, Charles University, Pilsen, Czech Republic
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19
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Targeting Myeloid-Derived Suppressor Cells in Cancer Immunotherapy. Cancers (Basel) 2020; 12:cancers12092626. [PMID: 32942545 PMCID: PMC7564060 DOI: 10.3390/cancers12092626] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2020] [Revised: 09/10/2020] [Accepted: 09/10/2020] [Indexed: 12/14/2022] Open
Abstract
Simple Summary Myeloid-Derived Suppressor Cells (MDSCs) have been regarded as the main promoters of cancer development in recent years. They can protect tumor cells from being eliminated by neutralizing the anti-tumor response mediated by T cells, macrophages and dendritic cells (DCs). Therefore, different treatment methods targeting MDSCs, including chemotherapy, radiotherapy and immunotherapy, have been developed and proven to effectively inhibit tumor expansion. Herein, we summarize the immunosuppressive role of MDSCs in the tumor microenvironment and some effective treatments targeting MDSCs, and discuss the differences between different therapies. Abstract Myeloid-derived suppressor cells (MDSCs), which are activated under pathological conditions, are a group of heterogeneous immature myeloid cells. MDSCs have potent capacities to support tumor growth via inhibition of the antitumoral immune response and/or the induction of immunosuppressive cells. In addition, multiple studies have demonstrated that MDSCs provide potential therapeutic targets for the elimination of immunosuppressive functions and the inhibition of tumor growth. The combination of targeting MDSCs and other therapeutic approaches has also demonstrated powerful antitumor effects. In this review, we summarize the characteristics of MDSCs in the tumor microenvironment (TME) and current strategies of cancer treatment by targeting MDSCs.
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20
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Kramer ED, Abrams SI. Granulocytic Myeloid-Derived Suppressor Cells as Negative Regulators of Anticancer Immunity. Front Immunol 2020; 11:1963. [PMID: 32983128 PMCID: PMC7481329 DOI: 10.3389/fimmu.2020.01963] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2020] [Accepted: 07/21/2020] [Indexed: 12/24/2022] Open
Abstract
The immune system plays a critical role in cancer progression and response to therapy. However, the immune system can be compromised during the neoplastic process. Notably, the myeloid lineage, which gives rise to granulocytic cells, including neutrophils, is a well-recognized target of tumor-mediated immune suppression. Ordinarily, granulocytic cells are integral for host defense, but in neoplasia the normal process of granulocyte differentiation (i.e., granulopoiesis) can be impaired leading instead to the formation of granulocytic (or PMN)-myeloid-derived suppressor cells (MDSCs). Such cells comprise various stages of myeloid differentiation and are defined functionally by their highly pro-tumorigenic and immune suppressive activities. Thus, considerable interest has been devoted to impeding the negative contributions of PMN-MDSCs to the antitumor response. Understanding their biology has the potential to unveil novel therapeutic opportunities to hamper PMN-MDSC production in the bone marrow, their mobilization, or their effector functions within the tumor microenvironment and, therefore, bolster anticancer therapies that require a competent myeloid compartment. In this review, we will highlight mechanisms by which the neoplastic process skews granulopoiesis to produce PMN-MDSCs, summarize mechanisms by which they execute their pro-tumorigenic activities and, lastly, underscore strategies to obstruct their role as negative regulators of antitumor immunity.
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Affiliation(s)
- Elliot D Kramer
- Department of Immunology, Roswell Park Comprehensive Cancer Center, Buffalo, NY, United States
| | - Scott I Abrams
- Department of Immunology, Roswell Park Comprehensive Cancer Center, Buffalo, NY, United States
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