1
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Zhu Q, Han Y, Wang X, Jia R, Zhang J, Liu M, Zhang W. Hypoxia exacerbates intestinal injury and inflammatory response mediated by myeloperoxidase during Salmonella Typhimurium infection in mice. Gut Pathog 2023; 15:62. [PMID: 38037141 PMCID: PMC10688069 DOI: 10.1186/s13099-023-00586-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/30/2023] [Accepted: 11/21/2023] [Indexed: 12/02/2023] Open
Abstract
BACKGROUND High-altitude exposure can cause oxidative stress damage in the intestine, which leads to increased intestinal permeability and bacterial translocation, resulting in local and systemic inflammation. Control of infection is critically dependent on the host's ability to kill pathogens with reactive oxygen species (ROS). Myeloperoxidase (MPO) targets ROS in pathogens. This study aimed to investigate the effects of hypoxia on the colonic mucosal barrier and myeloperoxidase (MPO)-mediated innate immune response in the colon. METHODS AND RESULTS Genetically engineered mice were exposed to a hypobaric oxygen chamber for 3 days and an inflammation model was established using Salmonella Typhimurium infection. We found that hypoxic exposure caused the development of exacerbated bacterial colitis and enhanced bacterial dissemination in MPO-deficient mice. Infection and disease severity were associated with significantly increased Ly6G+ neutrophil and F4/80+ macrophage counts in infected tissues, which is consistent with elevated proinflammatory cytokines and chemoattractant molecules. Hypoxia restrained antioxidant ability and MPO deficiency aggravated the respiratory burst in the colon. CONCLUSION Hypoxia can damage the colonic mucosa. MPO mediates the innate immune response and regulates the mucosal and systemic inflammatory responses to Salmonella infection during hypoxia.
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Affiliation(s)
- Qinfang Zhu
- Research Center for High Altitude Medicine, Key Laboratory of High Altitude Medicine (Ministry of Education), Key Laboratory of Application and Foundation for High Altitude Medicine Research in Qinghai Province (Qinghai-Utah Joint Research Key Lab for High Altitude Medicine), Qinghai University, Xining, China
| | - Ying Han
- Research Center for High Altitude Medicine, Key Laboratory of High Altitude Medicine (Ministry of Education), Key Laboratory of Application and Foundation for High Altitude Medicine Research in Qinghai Province (Qinghai-Utah Joint Research Key Lab for High Altitude Medicine), Qinghai University, Xining, China
| | - Xiaozhou Wang
- Research Center for High Altitude Medicine, Key Laboratory of High Altitude Medicine (Ministry of Education), Key Laboratory of Application and Foundation for High Altitude Medicine Research in Qinghai Province (Qinghai-Utah Joint Research Key Lab for High Altitude Medicine), Qinghai University, Xining, China
| | - Ruhan Jia
- Research Center for High Altitude Medicine, Key Laboratory of High Altitude Medicine (Ministry of Education), Key Laboratory of Application and Foundation for High Altitude Medicine Research in Qinghai Province (Qinghai-Utah Joint Research Key Lab for High Altitude Medicine), Qinghai University, Xining, China
| | - Jingxuan Zhang
- Research Center for High Altitude Medicine, Key Laboratory of High Altitude Medicine (Ministry of Education), Key Laboratory of Application and Foundation for High Altitude Medicine Research in Qinghai Province (Qinghai-Utah Joint Research Key Lab for High Altitude Medicine), Qinghai University, Xining, China
| | - Meiheng Liu
- Research Center for High Altitude Medicine, Key Laboratory of High Altitude Medicine (Ministry of Education), Key Laboratory of Application and Foundation for High Altitude Medicine Research in Qinghai Province (Qinghai-Utah Joint Research Key Lab for High Altitude Medicine), Qinghai University, Xining, China
| | - Wei Zhang
- Research Center for High Altitude Medicine, Key Laboratory of High Altitude Medicine (Ministry of Education), Key Laboratory of Application and Foundation for High Altitude Medicine Research in Qinghai Province (Qinghai-Utah Joint Research Key Lab for High Altitude Medicine), Qinghai University, Xining, China.
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2
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Mukherjee S, Skrede S, Haugstøyl M, López M, Fernø J. Peripheral and central macrophages in obesity. Front Endocrinol (Lausanne) 2023; 14:1232171. [PMID: 37720534 PMCID: PMC10501731 DOI: 10.3389/fendo.2023.1232171] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/31/2023] [Accepted: 07/28/2023] [Indexed: 09/19/2023] Open
Abstract
Obesity is associated with chronic, low-grade inflammation. Excessive nutrient intake causes adipose tissue expansion, which may in turn cause cellular stress that triggers infiltration of pro-inflammatory immune cells from the circulation as well as activation of cells that are residing in the adipose tissue. In particular, the adipose tissue macrophages (ATMs) are important in the pathogenesis of obesity. A pro-inflammatory activation is also found in other organs which are important for energy metabolism, such as the liver, muscle and the pancreas, which may stimulate the development of obesity-related co-morbidities, including insulin resistance, type 2 diabetes (T2D), cardiovascular disease (CVD) and non-alcoholic fatty liver disease (NAFLD). Interestingly, it is now clear that obesity-induced pro-inflammatory signaling also occurs in the central nervous system (CNS), and that pro-inflammatory activation of immune cells in the brain may be involved in appetite dysregulation and metabolic disturbances in obesity. More recently, it has become evident that microglia, the resident macrophages of the CNS that drive neuroinflammation, may also be activated in obesity and can be relevant for regulation of hypothalamic feeding circuits. In this review, we focus on the action of peripheral and central macrophages and their potential roles in metabolic disease, and how macrophages interact with other immune cells to promote inflammation during obesity.
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Affiliation(s)
- Sayani Mukherjee
- Hormone Laboratory, Department of Medical Biochemistry and Pharmacology, Haukeland University Hospital, Bergen, Norway
- Mohn Center for Diabetes Precision Medicine, Department of Clinical Science, University of Bergen, Bergen, Norway
- Department of Physiology, CIMUS, University of Santiago de Compostela, Santiago de Compostela, Spain
- CIBER Fisiopatología de la Obesidad y Nutrición (CIBERobn), Santiago de Compostela, Spain
| | - Silje Skrede
- Department of Clinical Science, Faculty of Medicine, University of Bergen, Bergen, Norway
- Department of Medical Biochemistry and Pharmacology, Haukeland University Hospital, Bergen, Norway
| | - Martha Haugstøyl
- Hormone Laboratory, Department of Medical Biochemistry and Pharmacology, Haukeland University Hospital, Bergen, Norway
- Mohn Center for Diabetes Precision Medicine, Department of Clinical Science, University of Bergen, Bergen, Norway
| | - Miguel López
- Department of Physiology, CIMUS, University of Santiago de Compostela, Santiago de Compostela, Spain
- CIBER Fisiopatología de la Obesidad y Nutrición (CIBERobn), Santiago de Compostela, Spain
| | - Johan Fernø
- Hormone Laboratory, Department of Medical Biochemistry and Pharmacology, Haukeland University Hospital, Bergen, Norway
- Mohn Center for Diabetes Precision Medicine, Department of Clinical Science, University of Bergen, Bergen, Norway
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3
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Hu J, Guan Z, Chen J. Multifunctional biomaterials that modulate oxygen levels in the tumor microenvironment. Cancer Lett 2021; 521:39-49. [PMID: 34419500 DOI: 10.1016/j.canlet.2021.08.019] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2021] [Revised: 08/11/2021] [Accepted: 08/17/2021] [Indexed: 12/27/2022]
Abstract
A characteristic feature of solid tumors is their low oxygen tension, which confers resistance to radiotherapy, photodynamic therapy, and chemotherapy. Therefore, to improve treatment outcomes, it is critical to develop biomaterials capable of targeted modulation of oxygen levels in tumors. In this review, we summarize four types of oxygen-modulating biomaterials, namely, oxygen-carrying biomaterials to deliver oxygen into tumors (e.g., perfluorocarbon and hemoglobin), oxygen-generating biomaterials to promote in situ oxygen generation (e.g., MnO2, catalase, and CuO), oxygen-consuming biomaterials to starve tumors (e.g., photosensitizer, glucose oxidase, and magnesium silicide), and oxygen-circulating biomaterials capable of both providing and consuming oxygen (e.g., ENBS-B). The current literature suggests that these biomaterials are useful for anticancer therapeutics. We present the key molecular mechanisms involved in modulating oxygen levels and the potential applications of these biomaterials in the context of hypoxic tumor treatment.
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Affiliation(s)
- Jinghui Hu
- School of Rehabilitation, Institute of Rehabilitation Engineering, Binzhou Medical University, Yantai, 264003, PR China
| | - Zhenxin Guan
- School of Pharmacy, The Key Laboratory of Prescription Effect and Clinical Evaluation of State Administration of Traditional Chinese Medicine of China, Binzhou Medical University, Yantai, 264003, PR China
| | - Jing Chen
- School of Pharmacy, The Key Laboratory of Prescription Effect and Clinical Evaluation of State Administration of Traditional Chinese Medicine of China, Binzhou Medical University, Yantai, 264003, PR China.
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4
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Mehta AK, Kadel S, Townsend MG, Oliwa M, Guerriero JL. Macrophage Biology and Mechanisms of Immune Suppression in Breast Cancer. Front Immunol 2021; 12:643771. [PMID: 33968034 PMCID: PMC8102870 DOI: 10.3389/fimmu.2021.643771] [Citation(s) in RCA: 77] [Impact Index Per Article: 25.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2020] [Accepted: 02/17/2021] [Indexed: 12/14/2022] Open
Abstract
Macrophages are crucial innate immune cells that maintain tissue homeostasis and defend against pathogens; however, their infiltration into tumors has been associated with adverse outcomes. Tumor-associated macrophages (TAMs) represent a significant component of the inflammatory infiltrate in breast tumors, and extensive infiltration of TAMs has been linked to poor prognosis in breast cancer. Here, we detail how TAMs impede a productive tumor immunity cycle by limiting antigen presentation and reducing activation of cytotoxic T lymphocytes (CTLs) while simultaneously supporting tumor cell survival, angiogenesis, and metastasis. There is an urgent need to overcome TAM-mediated immune suppression for durable anti-tumor immunity in breast cancer. To date, failure to fully characterize TAM biology and classify multiple subsets has hindered advancement in therapeutic targeting. In this regard, the complexity of TAMs has recently taken center stage owing to their subset diversity and tightly regulated molecular and metabolic phenotypes. In this review, we reveal major gaps in our knowledge of the functional and phenotypic characterization of TAM subsets associated with breast cancer, before and after treatment. Future work to characterize TAM subsets, location, and crosstalk with neighboring cells will be critical to counteract TAM pro-tumor functions and to identify novel TAM-modulating strategies and combinations that are likely to enhance current therapies and overcome chemo- and immuno-therapy resistance.
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Affiliation(s)
- Anita K Mehta
- Breast Tumor Immunology Laboratory, Dana-Farber Cancer Institute, Boston, MA, United States.,Division of Breast Surgery, Department of Surgery, Brigham and Women's Hospital, Boston, MA, United States
| | - Sapana Kadel
- Breast Tumor Immunology Laboratory, Dana-Farber Cancer Institute, Boston, MA, United States
| | - Madeline G Townsend
- Breast Tumor Immunology Laboratory, Dana-Farber Cancer Institute, Boston, MA, United States.,Division of Breast Surgery, Department of Surgery, Brigham and Women's Hospital, Boston, MA, United States
| | - Madisson Oliwa
- Breast Tumor Immunology Laboratory, Dana-Farber Cancer Institute, Boston, MA, United States.,Division of Breast Surgery, Department of Surgery, Brigham and Women's Hospital, Boston, MA, United States
| | - Jennifer L Guerriero
- Breast Tumor Immunology Laboratory, Dana-Farber Cancer Institute, Boston, MA, United States.,Division of Breast Surgery, Department of Surgery, Brigham and Women's Hospital, Boston, MA, United States
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5
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Berndt R, Albrecht M, Rusch R. Strategies to Overcome the Barrier of Ischemic Microenvironment in Cell Therapy of Cardiovascular Disease. Int J Mol Sci 2021; 22:ijms22052312. [PMID: 33669136 PMCID: PMC7956787 DOI: 10.3390/ijms22052312] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2021] [Revised: 02/21/2021] [Accepted: 02/22/2021] [Indexed: 12/11/2022] Open
Abstract
The transplantation of various immune cell types are promising approaches for the treatment of ischemic cardiovascular disease including myocardial infarction (MI) and peripheral arterial disease (PAD). Major limitation of these so-called Advanced Therapy Medicinal Products (ATMPs) is the ischemic microenvironment affecting cell homeostasis and limiting the demanded effect of the transplanted cell products. Accordingly, different clinical and experimental strategies have been evolved to overcome these obstacles. Here, we give a short review of the different experimental and clinical strategies to solve these issues due to ischemic cardiovascular disease.
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Affiliation(s)
- Rouven Berndt
- Clinic of Cardiovascular Surgery, University Hospital Schleswig-Holstein, 24105 Kiel, Germany;
- Vascular Research Center, University Hospital Schleswig-Holstein, 24105 Kiel, Germany
- Correspondence: ; Tel.: +49-(0431)-500-22033; Fax: +49-(0431)-500-22024
| | - Martin Albrecht
- Department of Anesthesiology and Intensive Care Medicine, University Hospital Schleswig-Holstein, 24105 Kiel, Germany;
| | - René Rusch
- Clinic of Cardiovascular Surgery, University Hospital Schleswig-Holstein, 24105 Kiel, Germany;
- Vascular Research Center, University Hospital Schleswig-Holstein, 24105 Kiel, Germany
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6
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Korbecki J, Kojder K, Barczak K, Simińska D, Gutowska I, Chlubek D, Baranowska-Bosiacka I. Hypoxia Alters the Expression of CC Chemokines and CC Chemokine Receptors in a Tumor-A Literature Review. Int J Mol Sci 2020; 21:ijms21165647. [PMID: 32781743 PMCID: PMC7460668 DOI: 10.3390/ijms21165647] [Citation(s) in RCA: 47] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Revised: 08/03/2020] [Accepted: 08/04/2020] [Indexed: 02/06/2023] Open
Abstract
Hypoxia, i.e., oxygen deficiency condition, is one of the most important factors promoting the growth of tumors. Since its effect on the chemokine system is crucial in understanding the changes in the recruitment of cells to a tumor niche, in this review we have gathered all the available data about the impact of hypoxia on β chemokines. In the introduction, we present the chronic (continuous, non-interrupted) and cycling (intermittent, transient) hypoxia together with the mechanisms of activation of hypoxia inducible factors (HIF-1 and HIF-2) and NF-κB. Then we describe the effect of hypoxia on the expression of chemokines with the CC motif: CCL1, CCL2, CCL3, CCL4, CCL5, CCL7, CCL8, CCL11, CCL13, CCL15, CCL16, CCL17, CCL18, CCL19, CCL20, CCL21, CCL22, CCL24, CCL25, CCL26, CCL27, CCL28 together with CC chemokine receptors: CCR1, CCR2, CCR3, CCR4, CCR5, CCR6, CCR7, CCR8, CCR9, and CCR10. To better understand the effect of hypoxia on neoplastic processes and changes in the expression of the described proteins, we summarize the available data in a table which shows the effect of individual chemokines on angiogenesis, lymphangiogenesis, and recruitment of eosinophils, myeloid-derived suppressor cells (MDSC), regulatory T cells (Treg), and tumor-associated macrophages (TAM) to a tumor niche.
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Affiliation(s)
- Jan Korbecki
- Department of Biochemistry and Medical Chemistry, Pomeranian Medical University in Szczecin, Powstańców Wielkopolskich 72, 70-111 Szczecin, Poland; (J.K.); (D.S.); (D.C.)
| | - Klaudyna Kojder
- Department of Anaesthesiology and Intensive Care, Pomeranian Medical University in Szczecin, Unii Lubelskiej 1, 71-281 Szczecin, Poland;
| | - Katarzyna Barczak
- Department of Conservative Dentistry and Endodontics, Pomeranian Medical University in Szczecin, Powstańców Wlkp. 72, 70-111 Szczecin, Poland;
| | - Donata Simińska
- Department of Biochemistry and Medical Chemistry, Pomeranian Medical University in Szczecin, Powstańców Wielkopolskich 72, 70-111 Szczecin, Poland; (J.K.); (D.S.); (D.C.)
| | - Izabela Gutowska
- Department of Medical Chemistry, Pomeranian Medical University in Szczecin, Powstańców Wlkp. 72, 70-111 Szczecin, Poland;
| | - Dariusz Chlubek
- Department of Biochemistry and Medical Chemistry, Pomeranian Medical University in Szczecin, Powstańców Wielkopolskich 72, 70-111 Szczecin, Poland; (J.K.); (D.S.); (D.C.)
| | - Irena Baranowska-Bosiacka
- Department of Biochemistry and Medical Chemistry, Pomeranian Medical University in Szczecin, Powstańców Wielkopolskich 72, 70-111 Szczecin, Poland; (J.K.); (D.S.); (D.C.)
- Correspondence: ; Tel.: +48-914661515; Fax: +48-914661516
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7
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Ravindran D, Cartland SP, Bursill CA, Kavurma MM. Broad-spectrum chemokine inhibition blocks inflammation-induced angiogenesis, but preserves ischemia-driven angiogenesis. FASEB J 2019; 33:13423-13434. [PMID: 31574232 DOI: 10.1096/fj.201900232rr] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
M3 is a broad-spectrum chemokine-binding protein that inactivates inflammatory chemokines, including CCL2, CCL5, and CX3CL1. The aim of this study was to compare whether M3 could inhibit angiogenesis driven by inflammation or ischemia. Here, apolipoprotein E-/- mice were injected with adenoviral M3 (AdM3) or control adenoviral green fluorescent protein (AdGFP) 3 d prior to stimulating angiogenesis using 2 established models that distinctly represent inflammatory or ischemia-driven angiogenesis, namely the periarterial femoral cuff and hind limb ischemia. AdM3 reduced intimal thickening, adventitial capillary density, and macrophage accumulation in femoral arteries 21 d after periarterial femoral cuff placement compared with AdGFP-treated mice (P < 0.05). AdM3 also reduced mRNA expression of proangiogenic VEGF, inflammatory markers IL-6 and IL-1β, and vascular smooth muscle cell (VSMC)-activated synthetic markers Krüppel-like family of transcription factor 4 (KLF4) and platelet-derived growth factor receptor β (PDGFRβ) in the inflammatory cuff model. In contrast, capillary density, VSMC content, blood flow perfusion, and VEGF gene expression were unaltered between groups in skeletal muscle following hind limb ischemia. In vitro, AdM3 significantly reduced human microvascular endothelial cell 1 proliferation, migration, and tubule formation by ∼17, 71.3, and 8.7% (P < 0.05) in macrophage-conditioned medium associating with reduced VEGF and hypoxia-inducible factor 1α mRNA but not in hypoxia (1% O2). Compared with AdGFP, AdM3 also inhibited VSMC proliferation and migration and reduced mRNA expression of KLF4 and PDGFRβ under inflammatory conditions. In contrast, AdM3 had no effect on VSMC processes in response to hypoxia in vitro. Our findings show that broad-spectrum inhibition of inflammatory chemokines by M3 inhibits inflammatory-driven but not ischemia-driven angiogenesis, presenting a novel strategy for the treatment of diseases associated with inflammatory-driven angiogenesis.-Ravindran, D., Cartland, S. P., Bursill, C. A., Kavurma, M. M. Broad-spectrum chemokine inhibition blocks inflammation-induced angiogenesis, but preserves ischemia-driven angiogenesis.
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Affiliation(s)
- Dhanya Ravindran
- The Heart Research Institute, Sydney, New South Wales, Australia.,Sydney Medical School, The University of Sydney, Sydney, New South Wales, Australia
| | - Siân P Cartland
- The Heart Research Institute, Sydney, New South Wales, Australia.,Sydney Medical School, The University of Sydney, Sydney, New South Wales, Australia
| | - Christina A Bursill
- Heart Health, South Australian Health and Medical Research Institute, Adelaide, South Australia, Australia
| | - Mary M Kavurma
- The Heart Research Institute, Sydney, New South Wales, Australia.,Sydney Medical School, The University of Sydney, Sydney, New South Wales, Australia
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8
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Nobre AR, Entenberg D, Wang Y, Condeelis J, Aguirre-Ghiso JA. The Different Routes to Metastasis via Hypoxia-Regulated Programs. Trends Cell Biol 2018; 28:941-956. [PMID: 30041830 PMCID: PMC6214449 DOI: 10.1016/j.tcb.2018.06.008] [Citation(s) in RCA: 73] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2018] [Revised: 06/28/2018] [Accepted: 06/29/2018] [Indexed: 12/18/2022]
Abstract
Hypoxia is linked to metastasis; however, how it affects metastatic progression is not clear due to limited consensus in the literature. We posit that this lack of consensus is due to hypoxia being studied using different approaches, such as in vitro, primary tumor, or metastasis assays in an isolated manner. Here, we review the pros and cons of in vitro hypoxia assays, highlight in vivo studies that inform on physiological hypoxia, and review the evidence that primary tumor hypoxia might influence the fate of disseminated tumor cells (DTCs) in secondary organs. Our analysis suggests that consensus can be reached by using in vivo methods of study, which also allow better modeling of how hypoxia affects DTC fate and metastasis.
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Affiliation(s)
- Ana Rita Nobre
- Division of Hematology and Oncology, Department of Medicine, Department of Otolaryngology, Department of Oncological Sciences, Tisch Cancer Institute, Black Family Stem Cell Institute, Mount Sinai School of Medicine, New York, NY 10029, USA; Abel Salazar School of Biomedicine, Porto University, Porto, Portugal; These authors contributed equally
| | - David Entenberg
- Department of Anatomy and Structural Biology, Gruss Lipper Biophotonics Center, Integrated Imaging Program, Albert Einstein College of Medicine, 1300 Morris Park Ave, Bronx, NY 10461, USA; These authors contributed equally
| | - Yarong Wang
- Department of Anatomy and Structural Biology, Gruss Lipper Biophotonics Center, Integrated Imaging Program, Albert Einstein College of Medicine, 1300 Morris Park Ave, Bronx, NY 10461, USA
| | - John Condeelis
- Department of Anatomy and Structural Biology, Gruss Lipper Biophotonics Center, Integrated Imaging Program, Albert Einstein College of Medicine, 1300 Morris Park Ave, Bronx, NY 10461, USA.
| | - Julio A Aguirre-Ghiso
- Division of Hematology and Oncology, Department of Medicine, Department of Otolaryngology, Department of Oncological Sciences, Tisch Cancer Institute, Black Family Stem Cell Institute, Mount Sinai School of Medicine, New York, NY 10029, USA.
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9
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Yang M, McKay D, Pollard JW, Lewis CE. Diverse Functions of Macrophages in Different Tumor Microenvironments. Cancer Res 2018; 78:5492-5503. [PMID: 30206177 PMCID: PMC6171744 DOI: 10.1158/0008-5472.can-18-1367] [Citation(s) in RCA: 280] [Impact Index Per Article: 46.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2018] [Revised: 06/21/2018] [Accepted: 07/31/2018] [Indexed: 12/13/2022]
Abstract
Tumor-associated macrophages are a major constituent of malignant tumors and are known to stimulate key steps in tumor progression. In our review in this journal in 2006, we postulated that functionally distinct subsets of these cells exist in different areas within solid tumors. Here, we review the many experimental and clinical studies conducted since then to investigate the function(s), regulation, and clinical significance of macrophages in these sites. The latter include three sites of cancer cell invasion, tumor nests, the tumor stroma, and areas close to, or distant from, the tumor vasculature. A more complete understanding of macrophage diversity in tumors could lead to the development of more selective therapies to restore the formidable, anticancer functions of these cells. Cancer Res; 78(19); 5492-503. ©2018 AACR.
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Affiliation(s)
- Ming Yang
- Department of Oncology & Metabolism, University of Sheffield Medical School, Sheffield, United Kingdom
| | - Daniel McKay
- Department of Oncology & Metabolism, University of Sheffield Medical School, Sheffield, United Kingdom
| | - Jeffrey W Pollard
- MRC Centre for Reproductive Health, College of Medicine and Veterinary Medicine, Queen's Medical Research Institute, The University of Edinburgh, Edinburgh, United Kingdom
| | - Claire E Lewis
- Department of Oncology & Metabolism, University of Sheffield Medical School, Sheffield, United Kingdom.
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10
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Mantovani A, Schioppa T, Biswas SK, Marchesi F, Allavena P, Sica A. Tumor-Associated Macrophages and Dendritic Cells as Prototypic Type II Polarized Myeloid Populations. TUMORI JOURNAL 2018; 89:459-68. [PMID: 14870765 DOI: 10.1177/030089160308900501] [Citation(s) in RCA: 50] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Environmental signals polarize mononuclear phagocytes which can express different functional programmes. Fully polarized type I and type II (or alternatively activated) macrophages are the extremes of a continuum of functional states. Tumor-derived and T cell-derived cytokines stimulate tumor associated macrophages (TAM) to acquire a polarized type II phenotype. These functionally polarized cells, and similarly oriented or immature dendritic cells present in tumors, play a key role in subversion of adaptive immunity and in inflammatory circuits which promote tumor growth and progression.
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11
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Schreiber T, Quinting T, Dittmer U, Fandrey J, Sutter K. Hypoxia-inducible factor 1α is Essential for Macrophage-mediated Erythroblast Proliferation in Acute Friend Retrovirus Infection. Sci Rep 2017; 7:17236. [PMID: 29222473 PMCID: PMC5722883 DOI: 10.1038/s41598-017-17324-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2017] [Accepted: 10/12/2017] [Indexed: 12/17/2022] Open
Abstract
Macrophages are the frontline of defence against foreign microorganisms, including bacteria, parasites, and viruses. During acute viral infection, macrophages must invade the inflamed tissue toward low oxygen concentrations, where genetic cellular responses depend on hypoxia-inducible factors (HIF). In the study reported here we investigated the role of HIF-1α in macrophage function during acute retroviral infection. Wild-type and myeloid cell-specific HIF-1α knockout mice were infected with Friend retrovirus (FV), and immune response was analysed 7 and 10 days after infection. FV infection led to increased spleen weight in wild-type and knockout mice, whereas a profound proliferation of erythroblasts was seen only in wild-type mice. The number of spleen-infiltrating macrophages was also significantly lower in knockout animals. Macrophage invasion after FV infection in wild-type mice led to elevated amounts of activated macrophage-stimulating 1 protein that resulted in massive proliferation of erythrocyte precursor cells. This proliferation was absent from knockout mice because of impaired invasion capabilities of HIF-1α-deficient macrophages. Our study elucidated a novel mechanism of FV-induced erythrocyte precursor cell proliferation.
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Affiliation(s)
- Timm Schreiber
- University of Duisburg-Essen, Institute of Physiology, Essen, Germany
| | - Theresa Quinting
- University of Duisburg-Essen, Institute of Physiology, Essen, Germany
| | - Ulf Dittmer
- University of Duisburg-Essen, Institute of Virology, Essen, Germany
| | - Joachim Fandrey
- University of Duisburg-Essen, Institute of Physiology, Essen, Germany.
| | - Kathrin Sutter
- University of Duisburg-Essen, Institute of Virology, Essen, Germany
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12
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Abstract
Human cancers exhibit formidable molecular heterogeneity, to a large extent accounting for the incomplete and transitory efficacy of current anti-cancer therapies. However, neoplastic cells alone do not manifest the disease, but conscript a battery of non-tumor cells to enable and sustain hallmark capabilities of cancer. Escaping immunosurveillance is one of such capabilities. Tumors evolve immunosuppressive microenvironment to subvert anti-tumor immunity. In this review, we will focus on tumor-associated myeloid cells, which constitute an essential part of the immune microenvironment and reciprocally interact with cancer cells to establish malignancy toward metastasis. The diversity and plasticity of these cells constitute another layer of heterogeneity, beyond the heterogeneity of cancer cells themselves. We envision that immune microenvironment co-evolves with the genetic heterogeneity of tumor. Addressing the question of how genetically distinct tumors shape and are shaped by unique immune microenvironment will provide an attractive rationale to develop novel immunotherapeutic modalities. Here, we discuss the complex nature of tumor microenvironment, with an emphasis on the cellular and functional heterogeneity among tumor-associated myeloid cells as well as immune environment heterogeneity in the context of a full spectrum of human breast cancers.
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13
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Hypoxia inducible factors are dispensable for myeloid cell migration into the inflamed mouse eye. Sci Rep 2017; 7:40830. [PMID: 28112274 PMCID: PMC5256030 DOI: 10.1038/srep40830] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2016] [Accepted: 12/12/2016] [Indexed: 12/19/2022] Open
Abstract
Hypoxia inducible factors (HIFs) are ubiquitously expressed transcription factors important for cell homeostasis during dynamic oxygen levels. Myeloid specific HIFs are crucial for aspects of myeloid cell function, including their ability to migrate into inflamed tissues during autoimmune disease. This contrasts with the concept that accumulation of myeloid cells at ischemic and hypoxic sites results from a lack of chemotactic responsiveness. Here we seek to address the role of HIFs in myeloid trafficking during inflammation in a mouse model of human uveitis. We show using mice with myeloid-specific Cre-deletion of HIFs that myeloid HIFs are dispensable for leukocyte migration into the inflamed eye. Myeloid-specific deletion of Hif1a, Epas1, or both together, had no impact on the number of myeloid cells migrating into the eye. Additionally, stabilization of HIF pathways via deletion of Vhl in myeloid cells had no impact on myeloid trafficking into the inflamed eye. Finally, we chemically induce hypoxemia via hemolytic anemia resulting in HIF stabilization within circulating leukocytes to demonstrate the dispensable role of HIFs in myeloid cell migration into the inflamed eye. These data suggest, contrary to previous reports, that HIF pathways in myeloid cells during inflammation and hypoxia are dispensable for myeloid cell tissue trafficking.
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Adipose Tissue Hypoxia in Obesity and Its Impact on Preadipocytes and Macrophages: Hypoxia Hypothesis. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2017; 960:305-326. [PMID: 28585205 DOI: 10.1007/978-3-319-48382-5_13] [Citation(s) in RCA: 70] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Obese subjects exhibit lower adipose tissue oxygen consumption in accordance with the lower adipose tissue blood flow. Thus, compared with lean subjects, obese subjects have 44% lower capillary density and 58% lower vascular endothelial growth factor (VEGF). The VEGF expression together with hypoxia-inducible transcription factor-1 (HIF-1) activity also requires phosphatidylinositol 3-kinase (PI3K)- and target of rapamycin (TOR)-mediated signaling. HIF-1alpha is an important signaling molecule for hypoxia to induce the inflammatory responses. Hypoxia affects a number of biological functions, such as angiogenesis, cell proliferation, apoptosis, inflammation and insulin resistance. Additionally, reactive oxygen radical (ROS) generation at mitochondria is responsible for propagation of the hypoxic signal. Actually mitochondrial ROS (mtROS) production, but not oxygen consumption is required for hypoxic HIF-1alpha protein stabilization. Adipocyte mitochondrial oxidative capacity is reduced in obese compared with non-obese adults. In this respect, mitochondrial dysfunction of adipocyte is associated with the overall adiposity. Furthermore, hypoxia also inhibits macrophage migration from the hypoxic adipose tissue. Alterations in oxygen availability of adipose tissue directly affect the macrophage polarization and are responsible from dysregulated adipocytokines production in obesity. Hypoxia also inhibits adipocyte differentiation from preadipocytes. In addition to stressed adipocytes, hypoxia contributes to immune cell immigration and activation which further aggravates adipose tissue fibrosis. Fibrosis is initiated in response to adipocyte hypertrophy in obesity.
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Ridiandries A, Tan JTM, Ravindran D, Williams H, Medbury HJ, Lindsay L, Hawkins C, Prosser HCG, Bursill CA. CC‐chemokine class inhibition attenuates pathological angiogenesis while preserving physiological angiogenesis. FASEB J 2016; 31:1179-1192. [DOI: 10.1096/fj.201600540r] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2016] [Accepted: 12/03/2016] [Indexed: 12/20/2022]
Affiliation(s)
- Anisyah Ridiandries
- Heart Research Institute Newtown New South Wales Australia
- Sydney Medical School University of Sydney Sydney New South Wales Australia
| | - Joanne T. M. Tan
- Heart Research Institute Newtown New South Wales Australia
- Sydney Medical School University of Sydney Sydney New South Wales Australia
| | - Dhanya Ravindran
- Heart Research Institute Newtown New South Wales Australia
- Sydney Medical School University of Sydney Sydney New South Wales Australia
| | - Helen Williams
- Sydney Medical School University of Sydney Sydney New South Wales Australia
- Vascular Biology Research Centre Department of Surgery Westmead Hospital University of Sydney Westmead New South Wales Australia
| | - Heather J. Medbury
- Sydney Medical School University of Sydney Sydney New South Wales Australia
- Vascular Biology Research Centre Department of Surgery Westmead Hospital University of Sydney Westmead New South Wales Australia
| | - Laura Lindsay
- Department of Anatomy and Histology School of Medical Sciences University of Sydney Sydney New South Wales Australia
| | - Clare Hawkins
- Heart Research Institute Newtown New South Wales Australia
- Sydney Medical School University of Sydney Sydney New South Wales Australia
| | - Hamish C. G. Prosser
- Heart Research Institute Newtown New South Wales Australia
- Sydney Medical School University of Sydney Sydney New South Wales Australia
| | - Christina A. Bursill
- Heart Research Institute Newtown New South Wales Australia
- Sydney Medical School University of Sydney Sydney New South Wales Australia
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Roberts SA, DiVito KA, Ligler FS, Adams AA, Daniele MA. Microvessel manifold for perfusion and media exchange in three-dimensional cell cultures. BIOMICROFLUIDICS 2016; 10:054109. [PMID: 27703595 PMCID: PMC5035297 DOI: 10.1063/1.4963145] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/21/2016] [Accepted: 09/08/2016] [Indexed: 05/08/2023]
Abstract
Integrating a perfusable microvasculature system in vitro is a substantial challenge for "on-chip" tissue models. We have developed an inclusive on-chip platform that is capable of maintaining laminar flow through porous biosynthetic microvessels. The biomimetic microfluidic device is able to deliver and generate a steady perfusion of media containing small-molecule nutrients, drugs, and gases in three-dimensional cell cultures, while replicating flow-induced mechanical stimuli. Here, we characterize the diffusion of small molecules from the perfusate, across the microvessel wall, and into the matrix of a 3D cell culture.
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Affiliation(s)
- Steven A Roberts
- Center for Bio/Molecular Science and Engineering , U.S. Naval Research Laboratory, 4555 Overlook Ave., Washington, DC 20375, USA
| | - Kyle A DiVito
- Center for Bio/Molecular Science and Engineering , U.S. Naval Research Laboratory, 4555 Overlook Ave., Washington, DC 20375, USA
| | - Frances S Ligler
- Joint Department of Biomedical Engineering, North Carolina State University and University of North Carolina , Chapel Hill, 911 Oval Dr., Raleigh, North Carolina 27695, USA
| | - André A Adams
- Center for Bio/Molecular Science and Engineering , U.S. Naval Research Laboratory, 4555 Overlook Ave., Washington, DC 20375, USA
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Patel A, Sant S. Hypoxic tumor microenvironment: Opportunities to develop targeted therapies. Biotechnol Adv 2016; 34:803-812. [PMID: 27143654 PMCID: PMC4947437 DOI: 10.1016/j.biotechadv.2016.04.005] [Citation(s) in RCA: 135] [Impact Index Per Article: 16.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2016] [Revised: 04/13/2016] [Accepted: 04/28/2016] [Indexed: 01/18/2023]
Abstract
In recent years, there has been great progress in the understanding of tumor biology and its surrounding microenvironment. Solid tumors create regions with low oxygen levels, generally termed as hypoxic regions. These hypoxic areas offer a tremendous opportunity to develop targeted therapies. Hypoxia is not a random by-product of the cellular milieu due to uncontrolled tumor growth; rather it is a constantly evolving participant in overall tumor growth and fate. This article reviews current trends and recent advances in drug therapies and delivery systems targeting hypoxia in the tumor microenvironment. In the first part, we give an account of important physicochemical changes and signaling pathways activated in the hypoxic microenvironment. This is then followed by various treatment strategies including hypoxia-sensitive signaling pathways and approaches to develop hypoxia-targeted drug delivery systems.
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Affiliation(s)
- Akhil Patel
- Department of Pharmaceutical Sciences, University of Pittsburgh School of Pharmacy, United States
| | - Shilpa Sant
- Department of Pharmaceutical Sciences, University of Pittsburgh School of Pharmacy, United States; Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA 15261, United States; McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, PA 15261, United States.
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Aggressiveness Niche: Can It Be the Foster Ground for Cancer Metastasis Precursors? Stem Cells Int 2016; 2016:4829106. [PMID: 27493669 PMCID: PMC4963571 DOI: 10.1155/2016/4829106] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2016] [Accepted: 06/15/2016] [Indexed: 12/26/2022] Open
Abstract
The relationship between tumor initiation and tumor progression can follow a linear projection in which all tumor cells are equally endowed with the ability to progress into metastasis. Alternatively, not all tumor cells are equal genetically and/or epigenetically, and only few cells are induced to become metastatic tumor cells. The location of these cells within the tumor can also impact the fate of these cells. The most inner core of a tumor where an elevated pressure of adverse conditions forms, such as necrosis-induced inflammation and hypoxia-induced immunosuppressive environment, seems to be the most fertile ground to generate such tumor cells with metastatic potential. Here we will call this necrotic/hypoxic core the “aggressiveness niche” and will present data to support its involvement in generating these metastatic precursors. Within this niche, interaction of hypoxia-surviving cells with the inflammatory microenvironment influenced by newly recruited mesenchymal stromal cells (MSCs), tumor-associated macrophages (TAMs), and other types of cells and the establishment of bidirectional interactions between them elevate the aggressiveness of these tumor cells. Additionally, immune evasion properties induced in these cells most likely contribute in the formation and maintenance of such aggressiveness niche.
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Whiteford JR, De Rossi G, Woodfin A. Mutually Supportive Mechanisms of Inflammation and Vascular Remodeling. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2016; 326:201-78. [PMID: 27572130 DOI: 10.1016/bs.ircmb.2016.05.001] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Chronic inflammation is often accompanied by angiogenesis, the development of new blood vessels from existing ones. This vascular response is a response to chronic hypoxia and/or ischemia, but is also contributory to the progression of disorders including atherosclerosis, arthritis, and tumor growth. Proinflammatory and proangiogenic mediators and signaling pathways form a complex and interrelated network in these conditions, and many factors exert multiple effects. Inflammation drives angiogenesis by direct and indirect mechanisms, promoting endothelial proliferation, migration, and vessel sprouting, but also by mediating extracellular matrix remodeling and release of sequestered growth factors, and recruitment of proangiogenic leukocyte subsets. The role of inflammation in promoting angiogenesis is well documented, but by facilitating greater infiltration of leukocytes and plasma proteins into inflamed tissues, angiogenesis can also propagate chronic inflammation. This review examines the mutually supportive relationship between angiogenesis and inflammation, and considers how these interactions might be exploited to promote resolution of chronic inflammatory or angiogenic disorders.
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Affiliation(s)
- J R Whiteford
- William Harvey Research Institute, Barts and London School of Medicine and Dentistry, Queen Mary College, University of London, London, United Kingdom
| | - G De Rossi
- William Harvey Research Institute, Barts and London School of Medicine and Dentistry, Queen Mary College, University of London, London, United Kingdom
| | - A Woodfin
- Cardiovascular Division, King's College, University of London, London, United Kingdom.
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The Response of Macrophages and Neutrophils to Hypoxia in the Context of Cancer and Other Inflammatory Diseases. Mediators Inflamm 2016; 2016:2053646. [PMID: 27034586 PMCID: PMC4789443 DOI: 10.1155/2016/2053646] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2015] [Accepted: 02/08/2016] [Indexed: 12/21/2022] Open
Abstract
Lack of oxygen (hypoxia) is a hallmark of a multitude of acute and chronic diseases and can be either beneficial or detrimental for organ restitution and recovery. In the context of inflammation, hypoxia is particularly important and can significantly influence the course of inflammatory diseases. Macrophages and neutrophils, the chief cellular components of innate immunity, display distinct properties when exposed to hypoxic conditions. Virtually every aspect of macrophage and neutrophil function is affected by hypoxia, amongst others, morphology, migration, chemotaxis, adherence to endothelial cells, bacterial killing, differentiation/polarization, and protumorigenic activity. Prominent arenas of macrophage and neutrophil function, for example, acute/chronic inflammation and the microenvironment of solid tumors, are characterized by low oxygen levels, demonstrating the paramount importance of the hypoxic response for proper function of these cells. Members of the hypoxia-inducible transcription factor (HIF) family emerged as pivotal molecular regulators of macrophages and neutrophils. In this review, we will summarize the molecular responses of macrophages and neutrophils to hypoxia in the context of cancer and other chronic inflammatory diseases and discuss the potential avenues for therapeutic intervention that arise from this knowledge.
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Huang WC, Shen MY, Chen HH, Lin SC, Chiang WH, Wu PH, Chang CW, Chiang CS, Chiu HC. Monocytic delivery of therapeutic oxygen bubbles for dual-modality treatment of tumor hypoxia. J Control Release 2015; 220:738-50. [DOI: 10.1016/j.jconrel.2015.09.016] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2015] [Revised: 08/31/2015] [Accepted: 09/09/2015] [Indexed: 01/24/2023]
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Huang WC, Chiang WH, Cheng YH, Lin WC, Yu CF, Yen CY, Yeh CK, Chern CS, Chiang CS, Chiu HC. Tumortropic monocyte-mediated delivery of echogenic polymer bubbles and therapeutic vesicles for chemotherapy of tumor hypoxia. Biomaterials 2015; 71:71-83. [DOI: 10.1016/j.biomaterials.2015.08.033] [Citation(s) in RCA: 81] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2015] [Revised: 08/14/2015] [Accepted: 08/16/2015] [Indexed: 10/23/2022]
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Sidaly R, Landin MA, Suo Z, Snead ML, Lyngstadaas SP, Reseland JE. Hypoxia increases the expression of enamel genes and cytokines in an ameloblast-derived cell line. Eur J Oral Sci 2015; 123:335-340. [PMID: 26193448 DOI: 10.1111/eos.12201] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/08/2015] [Indexed: 12/16/2022]
Abstract
The aim of this study was to investigate the effect of hypoxic conditions on the expression of enamel genes and on the secretion of alkaline phosphatase (ALP), lactate dehydrogenase (LDH), cytokines, and interleukins by an ameloblast-derived cell line. Murine ameloblast-derived cells (LS-8 cells) were exposed to 1% oxygen for 24 and 48 h and harvested after 1, 2, 3, and 7 d. The effect of culture in hypoxic conditions on the expression of structural enamel matrix genes and on the secretion of cytokines and interleukins, as well as ALP and LDH, into the cell-culture medium was calculated relative to the expression and secretion of these factors by untreated cells (controls) at each time point. Hypoxia increased expression of the structural enamel matrix genes amelogenin (Amelx), ameloblastin (Ambn), and enamelin (Enam), and the enamel protease matrix metalloproteinase-20 (Mmp20). Expression of hypoxia-inducible factor 1-alpha (Hif1α), and secretion of several vascularization factors and pro-inflammatory factors, were increased after 24 and 48 h of hypoxia. The ALP activity was reduced after 24 and 48 h of hypoxia, whereas the LDH level in the cell-culture medium was higher after 24 h of hypoxic conditions compared with 48 h. In conclusion, hypoxic exposure may disrupt the controlled fine-tuned expression and processing of enamel genes, and promote the secretion of pro-inflammatory factors.
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Affiliation(s)
- Rivan Sidaly
- Department of Biomaterials, Faculty of Dentistry, University of Oslo, Oslo, Norway
| | - Maria A Landin
- Department of Oral Biology, Faculty of Dentistry, University of Oslo, Oslo, Norway
| | - Zhenhe Suo
- Department of Pathology, The Norwegian Radium Hospital, Oslo University Hospital, Oslo, Norway
| | - Malcolm L Snead
- Center for Craniofacial Molecular Biology, The Herman Ostrow School of Dentistry, University of Southern California, Los Angeles, CA, USA
| | - Ståle P Lyngstadaas
- Department of Biomaterials, Faculty of Dentistry, University of Oslo, Oslo, Norway
| | - Janne E Reseland
- Department of Biomaterials, Faculty of Dentistry, University of Oslo, Oslo, Norway
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Tumor-associated macrophages are a useful biomarker to predict recurrence after surgical resection of nonfunctional pancreatic neuroendocrine tumors. Ann Surg 2015; 260:1088-94. [PMID: 25389924 DOI: 10.1097/sla.0000000000000262] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
OBJECTIVE Patients with nonfunctional pancreatic neuroendocrine tumors (NF-PNETs) have poorer survival than those with functional PNETs. Our objective was to identify risk factors for recurrence after resection to better define surveillance parameters to improve long-term outcomes. METHODS A retrospective analysis was performed for NF-PNET patients who underwent resection at the University of Michigan from 1995 to 2012. Immunohistochemical staining of tissues from patients with and without disease recurrence was performed for Ki-67 and the macrophage marker CD68, as tumor-associated macrophages are important for PNET development and progression. Clinicopathological factors and patient outcomes were measured. RESULTS Ninety-seven NF-PNET patients underwent surgical resection. There was a recurrence rate of 14.4% (14/97). The median time to recurrence was 0.61 years, with 10 (71%) patients recurring within the first 2 years. Six of 7 patients (86%) monitored at 6-month surveillance intervals were diagnosed with recurrence on their first computed tomographic scan or during the intervening intervals. By Cox proportional hazards analysis, the most significant independent risk factors for recurrence were higher grade, stage, and intraoperative blood loss. High CD68 score and Ki-67 index correlated with recurrence risk, and Ki-67 index inversely correlated with time to recurrence. In patients who otherwise had few risk factors, a high CD68 score was a significant prognostic factor for recurrence. CONCLUSIONS In patients with NF-PNETs, risk factors associated with recurrence were high EBL, grade, stage, CD68 score, and Ki-67 index. The CD68 score was an important prognostic factor in patients who otherwise had few clinicopathological risk factors; therefore, the CD68 score should be considered when planning surveillance strategies. We recommend that NF-PNET patients at high risk of recurrence undergo initial surveillance every 3 months for 2 years after surgery.
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Van Overmeire E, Laoui D, Keirsse J, Van Ginderachter JA, Sarukhan A. Mechanisms driving macrophage diversity and specialization in distinct tumor microenvironments and parallelisms with other tissues. Front Immunol 2014; 5:127. [PMID: 24723924 PMCID: PMC3972476 DOI: 10.3389/fimmu.2014.00127] [Citation(s) in RCA: 125] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2014] [Accepted: 03/12/2014] [Indexed: 12/12/2022] Open
Abstract
Macrophages are extremely versatile cells that adopt a distinct phenotype in response to a changing microenvironment. Consequently, macrophages are involved in diverse functions, ranging from organogenesis and tissue homeostasis to recognition and destruction of invading pathogens. In cancer, tumor-associated macrophages (TAM) often contribute to tumor progression by increasing cancer cell migration and invasiveness, stimulating angiogenesis, and suppressing anti-tumor immunity. Accumulating evidence suggests that these different functions could be exerted by specialized TAM subpopulations. Here, we discuss the potential underlying mechanisms regulating TAM specialization and elaborate on TAM heterogeneity in terms of their ontogeny, activation state, and intra-tumoral localization. In addition, parallels are drawn between TAM and macrophages in other tissues. Together, a better understanding of TAM diversity could provide a rationale for novel strategies aimed at targeting the most potent tumor-supporting macrophages.
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Affiliation(s)
- Eva Van Overmeire
- Myeloid Cell Immunology Laboratory, VIB , Brussels , Belgium ; Lab of Cellular and Molecular Immunology, Vrije Universiteit Brussel , Brussels , Belgium
| | - Damya Laoui
- Myeloid Cell Immunology Laboratory, VIB , Brussels , Belgium ; Lab of Cellular and Molecular Immunology, Vrije Universiteit Brussel , Brussels , Belgium
| | - Jiri Keirsse
- Myeloid Cell Immunology Laboratory, VIB , Brussels , Belgium ; Lab of Cellular and Molecular Immunology, Vrije Universiteit Brussel , Brussels , Belgium
| | - Jo A Van Ginderachter
- Myeloid Cell Immunology Laboratory, VIB , Brussels , Belgium ; Lab of Cellular and Molecular Immunology, Vrije Universiteit Brussel , Brussels , Belgium
| | - Adelaida Sarukhan
- Myeloid Cell Immunology Laboratory, VIB , Brussels , Belgium ; Lab of Cellular and Molecular Immunology, Vrije Universiteit Brussel , Brussels , Belgium ; Institut national de la santé et de la recherche médicale , Paris , France
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Strehl C, Fangradt M, Fearon U, Gaber T, Buttgereit F, Veale DJ. Hypoxia: how does the monocyte-macrophage system respond to changes in oxygen availability? J Leukoc Biol 2013; 95:233-41. [PMID: 24168857 DOI: 10.1189/jlb.1212627] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Hypoxia is an important feature of inflamed tissue, such as the RA joint. Activated monocytes/macrophages and endothelial cells play a pivotal role in the pathogenesis of RA, implicated in the mechanism of inflammation and erosion. During development, myeloid progenitor cells sequentially give rise to monoblasts, promonocytes, and monocytes that are released from the bone marrow into the bloodstream. After extravasation, monocytes differentiate into long-lived, tissue-specific macrophages or DCs. The effect of different oxygen concentrations experienced by these cells during maturation represents a novel aspect of this developmental process. In inflamed joint tissue, the microvascular architecture is highly dysregulated; thus, efficiency of oxygen supply to the synovium is poor. Therefore, invading cells must adapt instantaneously to changes in the oxygen level of the microenvironment. Angiogenesis is an early event in the inflammatory joint, which is important in enabling activated monocytes to enter via endothelial cells by active recruitment to expand the synovium into a "pannus", resulting in cartilage degradation and bone destruction. The increased metabolic turnover of the expanding synovial pannus outpaces the dysfunctional vascular supply, resulting in hypoxia. The abnormal bioenergetics of the microenvironment further promotes synovial cell invasiveness. In RA, joint hypoxia represents a potential threat to cell function and survival. Notably, oxygen availability is a crucial parameter in the cellular energy metabolism, itself an important factor in determining the function of immune cells.
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Affiliation(s)
- Cindy Strehl
- 2.Charité-Universitätsmedizin Berlin, Campus Mitte, Charitéplatz 1, 10117 Berlin, Germany.
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Obeid E, Nanda R, Fu YX, Olopade OI. The role of tumor-associated macrophages in breast cancer progression (review). Int J Oncol 2013; 43:5-12. [PMID: 23673510 PMCID: PMC3742164 DOI: 10.3892/ijo.2013.1938] [Citation(s) in RCA: 156] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2012] [Accepted: 02/20/2013] [Indexed: 02/07/2023] Open
Abstract
It is well established that the tumor microenvironment plays a major role in the aggressive behavior of malignant solid tumors. Among cell types associated with tumor microenvironment, tumor-associated macrophages (TAMs) are the most influential for tumor progression. Breast cancer is characterized by having a large population of TAMs, and experimental models have exposed multiple mechanisms by which TAMs interact with and influence the surrounding tumor cells. The process of metastasis involves tumor cells gaining access to the tissue outside the immediate tumor environment and invading the confining extracellular matrix (ECM). Supporting this process, TAMs secrete proangiogenic factors such as VEGF to build a network of vessels that provide nutrition for tumor cells, but also function as channels of transport into the ECM. Additionally, TAMs release factors to decrease the local pro-inflammatory antitumor response, suppressing it and providing a means of escape of the tumor cells. Similarly, hypoxia in the tumor microenvironment stimulates macrophages to further produce VEGF and suppress the T-cell immune responses, thus, enhancing the evasion of tumor cells and ultimately metastasis. Given the multiple roles of TAMS in breast cancer progression and metastasis, therapies targeting these cells are in development and demonstrate promising results.
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Affiliation(s)
- Elias Obeid
- Section of Hematology Medical and Oncology, Department of Medicine, University of Chicago, Chicago, IL 60637, USA
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Ling L, Maguire JJ, Davenport AP. Endothelin-2, the forgotten isoform: emerging role in the cardiovascular system, ovarian development, immunology and cancer. Br J Pharmacol 2013; 168:283-95. [PMID: 22118774 PMCID: PMC3572556 DOI: 10.1111/j.1476-5381.2011.01786.x] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2011] [Revised: 10/14/2011] [Accepted: 10/31/2011] [Indexed: 12/11/2022] Open
Abstract
Endothelin-2 [ET-2; also known as vasoactive intestinal contractor (VIC), in rodents] differs from endothelin-1 (ET-1) by only two amino acids, and unlike the third isoform, endothelin-3 (ET-3), it has the same affinity as ET-1 for both ET(A) and ET(B) receptors. It is often assumed that ET-2 would mimic the actions of the more abundant ET-1 and current pharmacological interventions used to inhibit the ET system would also block the actions of ET-2. These assumptions have focused research on ET-1 with ET-2 studied in much less detail. Recent research suggests that our understanding of the ET family requires re-evaluation. Although ET-2 is very similar in structure as well as pharmacology to ET-1, and may co-exist in the same tissue compartments, there is converging evidence for an important and distinct ET-2 pathway. Specifically is has been demonstrated that ET-2 has a key role in ovarian physiology, with ET-2-mediated contraction proposed as a final signal facilitating ovulation. Furthermore, ET-2 may also have a pathophysiological role in heart failure, immunology and cancer. Comparison of ET-2 versus ET-1 mRNA expression suggests this may be accomplished at the level of gene expression but differences may also exist in peptide synthesis by enzymes such as endothelin converting enzymes (ECEs) and chymase, which may allow the two pathways to be distinguished pharmacologically and become separate drug targets. LINKED ARTICLES This article is part of a themed section on Endothelin. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2013.168.issue-1.
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Affiliation(s)
- Lowell Ling
- Clinical Pharmacology Unit, University of Cambridge, Cambridge, UK
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29
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Curran CS, Keely PJ. Breast tumor and stromal cell responses to TGF-β and hypoxia in matrix deposition. Matrix Biol 2012; 32:95-105. [PMID: 23262216 DOI: 10.1016/j.matbio.2012.11.016] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2012] [Revised: 11/06/2012] [Accepted: 11/06/2012] [Indexed: 02/07/2023]
Abstract
The components that comprise the extracellular matrix (ECM) are integral to normal tissue homeostasis as well as the development and progression of breast tumors. The secretion, construction, and remodeling of the ECM are each regulated by a complex interplay between tumor cells, fibroblasts and macrophages. Transforming growth factor-β (TGF-β) is an essential molecule in regulating the cellular production of ECM molecules and the adhesive interactions of cells with the ECM. Additionally, hypoxic cell signals, initiated by oxygen deprivation, additional metabolic factors or receptor activation, are associated with ECM formation and the progression of breast cancer. Both TGF-β and hypoxic cell signals are implicated in the functional and morphological changes of cancer-associated-fibroblasts and tumor-associated-macrophages. Moreover, the enhanced recruitment of tumor and stromal cells in response to hypoxia-induced chemokines leads to increased ECM deposition and remodeling, increased blood vessel formation, and enhanced tumor migration. Thus, elucidation of the collaborative networks between tumor and stromal cells in response to the combined signals of TGF-β and hypoxia may yield insight into treatment parameters that target both tumor and stromal cells.
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Affiliation(s)
- Colleen S Curran
- Laboratory of Cell and Molecular Biology, Department of Cell and Regenerative Biology, University of Wisconsin School of Medicine and Public Health, Madison, WI 53706, United States.
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Riboldi E, Porta C, Morlacchi S, Viola A, Mantovani A, Sica A. Hypoxia-mediated regulation of macrophage functions in pathophysiology. Int Immunol 2012. [PMID: 23179187 DOI: 10.1093/intimm/dxs110] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Oxygen availability affects cell differentiation, survival and function, with profound consequences on tissue homeostasis, inflammation and immunity. A gradient of oxygen levels is present in most organs of the body as well as in virtually every site of inflammation, damaged or pathological tissue. As a consequence, infiltrating leukocytes, macrophages in particular, are equipped with the capacity to shift their metabolism to anaerobic glycolysis, to generate ATP and induce the expression of factors that increase the supply of oxygen and nutrients. Strikingly, low oxygen conditions (hypoxia) and inflammatory signals share selected transcriptional events, including the activation of members of both the hypoxia-inducible factor and nuclear factor κB families, which may converge to activate specific cell programs. In the pathological response to hypoxia, cancer in particular, macrophages act as orchestrators of disease evolution and their number can be used as a prognostic marker. Here we review mechanisms of macrophage adaptation to hypoxia, their role in disease as well as new perspectives for their therapeutic targeting.
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Affiliation(s)
- Elena Riboldi
- Department of Pharmaceutical Sciences, Università del Piemonte Orientale 'Amedeo Avogadro', Novara 28100, Italy
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Segal RA, Diegelmann RF, Ward KR, Reynolds A. A Differential Equation Model of Collagen Accumulation in a Healing Wound. Bull Math Biol 2012; 74:2165-82. [DOI: 10.1007/s11538-012-9751-z] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2011] [Accepted: 07/02/2012] [Indexed: 01/09/2023]
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Hypoxic regulation of mesenchymal stem cell migration: the role of RhoA and HIF-1α. Cell Biol Int 2012; 35:981-9. [PMID: 21574962 DOI: 10.1042/cbi20100733] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
A variety of pathologies such as skeletal fracture, neoplasia and inflammation compromise tissue perfusion and thereby decrease tissue oxygen tension. We and others have demonstrated that hypoxia is a potent stimulant for MSC (mesenchymal stem cell) recruitment and differentiation, yet to date little research has focused on the effects of oxygen tension on MSC migration. In the present study, we examined the effects of hypoxia and the potential role of the GTPase RhoA and HIF-1α (hypoxia-inducible factor 1α) on MSC migration. Our results demonstrate that hypoxia decreases MSC migration through an HIF-1α and RhoA-mediated pathway. The active GTP-bound form of RhoA was reduced in 1% oxygen, whereas activation of RhoA under hypoxic conditions rescued migration. Furthermore, stabilization of HIF-1α under normoxic conditions attenuated cell migration similar to that of hypoxia. These results suggest that hypoxia negatively affects MSC migration by regulating activation of GTPases. These results highlight the importance of oxygen in regulating the recruitment of progenitor cells to areas of ischaemic tissue damage.
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Dietz I, Jerchel S, Szaszák M, Shima K, Rupp J. When oxygen runs short: the microenvironment drives host-pathogen interactions. Microbes Infect 2011; 14:311-6. [PMID: 22133978 DOI: 10.1016/j.micinf.2011.11.003] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2011] [Revised: 11/07/2011] [Accepted: 11/07/2011] [Indexed: 01/13/2023]
Abstract
Pathogens that colonize or infect the human body have to face varying oxygen concentrations within different organs. Inflammation itself promotes oxygen consumption within affected tissues and creates a low oxygen environment. As a consequence, pathogens and the host immune system have to adapt to rapid changes in oxygen availability. Here we summarize recent findings on the adaptation of pathogens, host defense mechanisms and treatment strategies against intracellular pathogens in a low oxygen environment.
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Affiliation(s)
- Inga Dietz
- Institute of Medical Microbiology and Hygiene, University of Lübeck, Ratzeburger Allee 160, 23538 Lübeck, Germany
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Hwang HS, Kwon HS, Sohn IS, Park YW, Kim YH. Increased CXCL12 expression in the placentae of women with pre-eclampsia. Eur J Obstet Gynecol Reprod Biol 2011; 160:137-41. [PMID: 22071114 DOI: 10.1016/j.ejogrb.2011.10.007] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2011] [Revised: 07/25/2011] [Accepted: 10/12/2011] [Indexed: 10/15/2022]
Abstract
OBJECTIVE To investigate the expression pattern of CXC chemokine ligand-12 (CXCL12) in the placentae of normal and pre-eclamptic women. STUDY DESIGN Twenty-five women with severe pre-eclampsia and 30 normotensive women, matched for gestational age, were enrolled in the study. Placental tissue from each woman was collected following delivery by caesarean section. Quantitative reverse transcription polymerase chain reaction, Western blot analysis and immunohistochemical staining were performed for mRNA expression, quantification and tissue localization of CXCL12 in each placenta. RESULTS CXCL12 expression was greater in pre-eclamptic placentae compared with normal placentae. CXCL12 was detected in most placental tissue cells by immunohistochemical staining. CXCL12 immunoreactivity was significantly greater in syncytiotrophoblasts of pre-eclamptic placentae compared with normal placentae. However, there was no significant difference in CXCL12 immunoreactivity in other tissues between the two groups. CONCLUSION CXCL12 expression is significantly greater in the placentae of pre-eclamptic women compared with normal women. This may represent part of a compensatory mechanism for pre-eclampsia.
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Affiliation(s)
- Han Sung Hwang
- Department of Obstetrics and Gynaecology, Konkuk University Medical Centre, Konkuk University School of Medicine, Seoul, Republic of Korea
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35
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Hypoxia reduces the response of human adipocytes towards TNFα resulting in reduced NF-κB signaling and MCP-1 secretion. Int J Obes (Lond) 2011; 36:986-92. [PMID: 22005720 DOI: 10.1038/ijo.2011.200] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
OBJECTIVE Obesity is associated with adipose tissue hypoxia, and is thought to be linked to the chronic low-grade inflammation of adipose tissue, although the precise mechanism has remained unclear. In this study, we investigated the effect of a prominent hypoxia on human primary adipocyte secretion and tumor necrosis factor alpha (TNFα)-induced nuclear factor-κB (NF-κB) signaling. RESULTS Using cytokine array and ELISA analysis, we compared the secretion patterns of normoxic and hypoxic (1% O(2)) adipocytes and observed various alterations in adipokine release. We could reproduce known alterations like an induction of interleukin (IL)-6, vascular endothelial growth factor, leptin and a reduction in adiponectin release under hypoxia. Interestingly, we observed a significant reduction in the secretion of macrophage chemotactic protein (MCP)-1 and other NF-κB-related genes, such as growth-regulated oncogene-α, eotaxin and soluble TNF-Receptor1 (TNF-R1) under hypoxia. TNFα stimulation of hypoxic adipocytes resulted in a significantly reduced phosphorylation of NF-κB and its inhibitor IκBα compared with normoxic cells. Furthermore, chronic treatment of hypoxic adipocytes with TNFα resulted in an expected higher secretion of the chemokines MCP-1 and IL-8, but under hypoxia, the secretion level was substantially lower than that under normoxia. This reduction in protein release was accompanied by a reduced mRNA expression of MCP-1, whereas IL-8 mRNA expression was not altered. Additionally, we observed a significantly reduced expression of the TNF-receptor TNF-R1, possibly being one cause for the reduced responsiveness of hypoxic adipocytes towards TNFα stimulation. CONCLUSION In conclusion, human primary adipocytes show a basal and TNFα-induced reduction of MCP-1 release under hypoxia. This effect may be due to a reduced expression of TNF-R1 and therefore attenuated TNFα-induced NF-κB signaling. These observations demonstrate a reduced responsiveness of hypoxic adipocytes towards inflammatory stimuli like TNFα, which may represent an adaptation process to maintain adipose tissue function under hypoxia and inflammatory conditions.
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Ruiz-García A, Monsalve E, Novellasdemunt L, Navarro-Sabaté A, Manzano A, Rivero S, Castrillo A, Casado M, Laborda J, Bartrons R, Díaz-Guerra MJM. Cooperation of adenosine with macrophage Toll-4 receptor agonists leads to increased glycolytic flux through the enhanced expression of PFKFB3 gene. J Biol Chem 2011; 286:19247-58. [PMID: 21464136 DOI: 10.1074/jbc.m110.190298] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Macrophages activated through Toll receptor triggering increase the expression of the A(2A) and A(2B) adenosine receptors. In this study, we show that adenosine receptor activation enhances LPS-induced pfkfb3 expression, resulting in an increase of the key glycolytic allosteric regulator fructose 2,6-bisphosphate and the glycolytic flux. Using shRNA and differential expression of A(2A) and A(2B) receptors, we demonstrate that the A(2A) receptor mediates, in part, the induction of pfkfb3 by LPS, whereas the A(2B) receptor, with lower adenosine affinity, cooperates when high adenosine levels are present. pfkfb3 promoter sequence deletion analysis, site-directed mutagenesis, and inhibition by shRNAs demonstrated that HIF1α is a key transcription factor driving pfkfb3 expression following macrophage activation by LPS, whereas synergic induction of pfkfb3 expression observed with the A(2) receptor agonists seems to depend on Sp1 activity. Furthermore, levels of phospho-AMP kinase also increase, arguing for increased PFKFB3 activity by phosphorylation in long term LPS-activated macrophages. Taken together, our results show that, in macrophages, endogenously generated adenosine cooperates with bacterial components to increase PFKFB3 isozyme activity, resulting in greater fructose 2,6-bisphosphate accumulation. This process enhances the glycolytic flux and favors ATP generation helping to develop and maintain the long term defensive and reparative functions of the macrophages.
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Affiliation(s)
- Almudena Ruiz-García
- Facultad de Medicina, Centro Regional de Investigaciones Biomédicas, Albacete, Spain
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37
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Allen M, Louise Jones J. Jekyll and Hyde: the role of the microenvironment on the progression of cancer. J Pathol 2010; 223:162-76. [PMID: 21125673 DOI: 10.1002/path.2803] [Citation(s) in RCA: 256] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2010] [Revised: 10/01/2010] [Accepted: 10/01/2010] [Indexed: 12/13/2022]
Abstract
It is now recognized that the host microenvironment undergoes extensive change during the evolution and progression of cancer. This involves the generation of cancer-associated fibroblasts (CAFs), which, through release of growth factors and cytokines, lead to enhanced angiogenesis, increased tumour growth and invasion. It has also been demonstrated that CAFs may modulate the cancer stem cell (CSC) phenotype, which has therapeutic implications. The altered fibroblast phenotype also contributes to the development of an altered extracellular matrix (ECM), with synthesis of ECM isoforms rarely found in normal tissues, including tenascin-C isoforms and the fibronectin EDA isoform. There is also emerging evidence of how the tensile strength of the tumour-associated ECM may be modified and lead to altered signalling in tumour cells. The hypoxic environment of the tumour stimulates angiogenesis and also impacts on other aspects of cell signalling, including the c-met pathway and lysyl oxidase-mediated signalling, which can directly promote tumour cell invasion. The inflammatory infiltrate associated with many solid tumours also modulates tumour function, having both anti- and pro-tumour effects. All of these components of the microenvironment provide potential targets for therapeutic attack, with a number of molecules already in clinical trials. It is also becoming evident that characterizing the tumour microenvironment can provide important prognostic and predictive information about tumours, independent of the tumour cell phenotype.
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Affiliation(s)
- Michael Allen
- Centre for Tumour Biology, Barts Cancer Institute, Barts and the London School of Medicine and Dentistry, London, UK
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38
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Dziurla R, Gaber T, Fangradt M, Hahne M, Tripmacher R, Kolar P, Spies CM, Burmester GR, Buttgereit F. Effects of hypoxia and/or lack of glucose on cellular energy metabolism and cytokine production in stimulated human CD4+ T lymphocytes. Immunol Lett 2010; 131:97-105. [PMID: 20206208 DOI: 10.1016/j.imlet.2010.02.008] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2009] [Revised: 02/23/2010] [Accepted: 02/24/2010] [Indexed: 02/05/2023]
Abstract
Oxidative phosphorylation and/or glycolysis provide energy, mainly in the form of ATP, which ensures proper functioning of immune cells such as CD4(+) T lymphocytes. However, the main substrates, namely oxygen and glucose, are known to remain for a relatively short time in the inflamed tissue and in other clinical situations where immune cells need to function properly. Therefore, we examined the effect of hypoxia and/or lack of glucose on cellular energy metabolism and on cytokine secretion in stimulated human CD4(+) T lymphocytes. Human CD4(+) T cells were MACS-isolated using peripheral blood obtained from healthy donors. Stimulated cells were incubated in medium with or without glucose for 6h in a sealed chamber which led to cumulative hypoxia. During this incubation period, (i) oxygen saturation was measured continuously using a Clark-type electrode, and (ii) samples were taken at different time points in order to quantify for each the viability of cells, intracellular reactive oxygen species (iROS), ATP levels, glycolytic enzyme activity, mRNA expression of hexokinase-1 and superoxide dismutase-1, and concentrations of several different cytokines. Stimulated CD4(+) T cells which were incubated under normoxic conditions served as controls. Under hypoxic conditions, lack of glucose exerted a biphasic effect on cellular oxygen consumption: initially higher but later lower respiration rates were measured when compared to conditions where glucose was available. Lack of glucose strongly increased the number of dead cells and the formation of iROS under normoxia but not under hypoxia. Under both normoxic and hypoxic conditions, intracellular ATP levels remained almost unchanged during the incubation period if glucose was present, but decreased significantly in the absence of glucose, despite the enhanced glycolytic enzyme activity. Measurements of stimulated cytokine production demonstrated (i) that cumulative hypoxia stimulates especially the secretion of IL-1beta, IL-10 and IL-8, and (ii) that lack of glucose results in lower cytokine concentrations. We demonstrate that CD4(+) T cells are highly adaptive in bioenergetic terms which ensure their proper function under extreme conditions of glucose and/or oxygen availability as found under physiological and pathophysiological conditions. Hypoxia seems to facilitate inflammatory reactions and angiogenesis.
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Affiliation(s)
- R Dziurla
- Department of Rheumatology and Clinical Immunology, Charité University Hospital, Charitéplatz 1, Berlin, Germany.
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39
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Zhang Z, Liu Q, Che Y, Yuan X, Dai L, Zeng B, Jiao G, Zhang Y, Wu X, Yu Y, Zhang Y, Yang R. Antigen presentation by dendritic cells in tumors is disrupted by altered metabolism that involves pyruvate kinase M2 and its interaction with SOCS3. Cancer Res 2009; 70:89-98. [PMID: 19996282 DOI: 10.1158/0008-5472.can-09-2970] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Dendritic cell (DC) function is negatively affected by tumors and tumor-derived factors, but little is known about the underlying mechanisms. Here, we show that intracellular SOCS3 in DCs binds to pyruvate kinase type M2 (M2-PK), which plays a critical role in ATP production through glycolysis. The interaction of SOCS3 with M2-PK reduced ATP production and impaired DC-based immunotherapy against tumors. Thus, SOCS3, which has been shown to be upregulated by tumor-derived factors, interacts with M2-PK to decrease ATP production, causing DC dysfunction. These dysfunctional DCs have a reduced ability to present antigens. Alteration of DC metabolism mediated by SOCS3 represents a novel mechanism for DC dysfunction in the tumor microenvironment.
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Affiliation(s)
- Zhuohan Zhang
- Department of Immunology, Nankai University School of Medicine and Key Laboratory of Bioactive Materials, Ministry of Education, Nankai University, Tianjin, People's Republic of China
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Jin S, Chen Z, Lunan Y, Zeng Y, Wen T, Li B, Zhao J, Wang W, Xu M, Yang J. Can Liver Transplantation Achieve Similar Effects at High Altitudes Compared With Plains: Case Report. Transplant Proc 2009; 41:2003-5. [DOI: 10.1016/j.transproceed.2009.01.115] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2008] [Revised: 11/21/2008] [Accepted: 01/08/2009] [Indexed: 10/20/2022]
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41
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Staiano RI, Granata F, Secondo A, Petraroli A, Loffredo S, Frattini A, Annunziato L, Marone G, Triggiani M. Expression and function of Na+/Ca2+ exchangers 1 and 3 in human macrophages and monocytes. Eur J Immunol 2009; 39:1405-18. [DOI: 10.1002/eji.200838792] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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42
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Abstract
Recent studies consistently support a hypoxia response in the adipose tissue in obese animals. The observations have led to the formation of an exciting concept, adipose tissue hypoxia (ATH), in the understanding of major disorders associated with obesity. ATH may provide cellular mechanisms for chronic inflammation, macrophage infiltration, adiponectin reduction, leptin elevation, adipocyte death, endoplasmic reticulum stress and mitochondrial dysfunction in white adipose tissue in obesity. The concept suggests that inhibition of adipogenesis and triglyceride synthesis by hypoxia may be a new mechanism for elevated free fatty acids in the circulation in obesity. ATH may represent a unified cellular mechanism for a variety of metabolic disorders and insulin resistance in patients with metabolic syndrome. It suggests a new mechanism of pathogenesis of insulin resistance and inflammation in obstructive sleep apnea. In addition, it may help us to understand the beneficial effects of caloric restriction, physical exercise and angiotensin II inhibitors in the improvement of insulin sensitivity. In this review article, literatures are reviewed to summarize the evidence and possible cellular mechanisms of ATH. The directions and road blocks in the future studies are analyzed.
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Bosco MC, Puppo M, Blengio F, Fraone T, Cappello P, Giovarelli M, Varesio L. Monocytes and dendritic cells in a hypoxic environment: Spotlights on chemotaxis and migration. Immunobiology 2008; 213:733-49. [DOI: 10.1016/j.imbio.2008.07.031] [Citation(s) in RCA: 107] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2008] [Accepted: 07/23/2008] [Indexed: 01/20/2023]
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44
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Egeblad M, Ewald AJ, Askautrud HA, Truitt ML, Welm BE, Bainbridge E, Peeters G, Krummel MF, Werb Z. Visualizing stromal cell dynamics in different tumor microenvironments by spinning disk confocal microscopy. Dis Model Mech 2008; 1:155-67; discussion 165. [PMID: 19048079 DOI: 10.1242/dmm.000596] [Citation(s) in RCA: 158] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2008] [Accepted: 06/18/2008] [Indexed: 02/06/2023] Open
Abstract
The tumor microenvironment consists of stromal cells and extracellular factors that evolve in parallel with carcinoma cells. To gain insights into the activities of stromal cell populations, we developed and applied multicolor imaging techniques to analyze the behavior of these cells within different tumor microenvironments in the same live mouse. We found that regulatory T-lymphocytes (Tregs) migrated in proximity to blood vessels. Dendritic-like cells, myeloid cells and carcinoma-associated fibroblasts all exhibited higher motility in the microenvironment at the tumor periphery than within the tumor mass. Since oxygen levels differ between tumor microenvironments, we tested if acute hypoxia could account for the differences in cell migration. Direct visualization revealed that Tregs ceased migration under acute systemic hypoxia, whereas myeloid cells continued migrating. In the same mouse and microenvironment, we experimentally subdivided the myeloid cell population and revealed that uptake of fluorescent dextran defined a low-motility subpopulation expressing markers of tumor-promoting, alternatively activated macrophages. In contrast, fluorescent anti-Gr1 antibodies marked myeloid cells patrolling inside tumor vessels and in the stroma. Our techniques allow real-time combinatorial analysis of cell populations based on spatial location, gene expression, behavior and cell surface molecules within intact tumors. The techniques are not limited to investigations in cancer, but could give new insights into cell behavior more broadly in development and disease.
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Affiliation(s)
- Mikala Egeblad
- Department of Anatomy, University of California, San Francisco, 513 Parnassus Avenue, San Francisco, CA 94143, USA.
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45
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Tripmacher R, Gaber T, Dziurla R, Häupl T, Erekul K, Grützkau A, Tschirschmann M, Scheffold A, Radbruch A, Burmester GR, Buttgereit F. Human CD4(+) T cells maintain specific functions even under conditions of extremely restricted ATP production. Eur J Immunol 2008; 38:1631-42. [PMID: 18493983 DOI: 10.1002/eji.200738047] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
We investigated the energy-adaptive potential of human CD4(+) T cells under conditions of impaired oxidative phosphorylation (OXPHOS) and/or low glucose (inhibiting glycolysis). These cells often encounter these conditions when executing their functions in injured/inflamed tissues, even though T cells themselves require constant and adequate energy supply via ATP. We assessed two specific functions, cytokine synthesis and proliferation, and addressed whether adaptive characteristics also emerged in vivo. In glucose-containing medium, both cytokine production and proliferation were unaffected, even under complete OXPHOS suppression. Only when glucose was also absent were these functions significantly decreased. Partial recovery of OXPHOS and induced glycolysis were crucial for the maintenance of cellular energy supply. Adaptive regulatory mechanisms are clinically relevant because hypoxia up-regulates glycolytic genes but down-regulates OXPHOS genes in vivo. Our data demonstrate an unexpectedly high, clinically relevant adaptive potential of human CD4(+) T cells to maintain specific functions even under severely impaired bioenergetic conditions.
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Affiliation(s)
- Robert Tripmacher
- Department of Rheumatology and Clinical Immunology, Charité University Medicine, Berlin, Germany
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46
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Piovan E, Tosello V, Indraccolo S, Masiero M, Persano L, Esposito G, Zamarchi R, Ponzoni M, Chieco-Bianchi L, Dalla-Favera R, Amadori A. Differential regulation of hypoxia-induced CXCR4 triggering during B-cell development and lymphomagenesis. Cancer Res 2007; 67:8605-14. [PMID: 17875700 DOI: 10.1158/0008-5472.can-06-4722] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The chemokine receptor CXCR4 plays a central role in organ-specific homing and tumor spreading and is induced by hypoxia. B lymphocytes are exposed to low oxygen tensions during their development, but the influence of hypoxia on their physiology is poorly understood. Here, we show that hypoxia is associated with up-regulation of CXCR4 expression in human normal and malignant B cells, through both transcriptional and posttranslational mechanisms. However, a dichotomic functional response to CXCR4 triggering was observed: both peripheral B cells and lymphomas arising from mature B cells displayed increased responses to CXCR4 triggering under hypoxia, whereas germinal center (GC) B cells as well as GC-derived lymphomas showed CXCR4 receptor desensitization. This phenomenon was associated with differential modulation of key signal-transducing molecules, including mitogen-activated protein kinase phosphatase-1 and regulator of G protein signaling molecule-1. The unresponsiveness of GC-derived lymphomatous B cells to CXCR4 triggering under hypoxia may have implications for the development and pathogenesis of GC-derived lymphoid tumors.
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MESH Headings
- Animals
- B-Lymphocytes/metabolism
- B-Lymphocytes/pathology
- B-Lymphocytes/physiology
- Burkitt Lymphoma/genetics
- Burkitt Lymphoma/metabolism
- Burkitt Lymphoma/pathology
- Cell Hypoxia/physiology
- Cell Line, Tumor
- Dual Specificity Phosphatase 1/biosynthesis
- Dual Specificity Phosphatase 1/genetics
- Humans
- Hypoxia-Inducible Factor 1, alpha Subunit/genetics
- Hypoxia-Inducible Factor 1, alpha Subunit/metabolism
- Lymphoma, B-Cell/genetics
- Lymphoma, B-Cell/metabolism
- Lymphoma, B-Cell/pathology
- Mice
- Mice, SCID
- RGS Proteins/biosynthesis
- RGS Proteins/genetics
- RNA, Small Interfering/genetics
- Receptors, CXCR4/biosynthesis
- Receptors, CXCR4/genetics
- Transcription, Genetic
- Up-Regulation
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Affiliation(s)
- Erich Piovan
- Oncology Section, Department of Oncology and Surgical Sciences, University of Padova, Italy
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47
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Lewis CE, Hughes R. Inflammation and breast cancer. Microenvironmental factors regulating macrophage function in breast tumours: hypoxia and angiopoietin-2. Breast Cancer Res 2007; 9:209. [PMID: 17601353 PMCID: PMC1929095 DOI: 10.1186/bcr1679] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Considerable evidence has now accumulated for tumour-associated macrophages stimulating key aspects of tumour progression, including the proliferation, survival and metastasis of tumour cells, tumour angiogenesis and suppression of the anti-tumour functions of other immune effectors at the tumour site. Tumour micro-environmental factors such as hypoxia have profound, direct effects on these cells, stimulating many of their pro-tumour functions. Hypoxia also does so indirectly by stimulating the release of the cytokine angiopoietin-2 from tumour cells and tumour blood vessels. This in turn then recruits Tie-2-expressing monocytes into tumours from the bloodstream and inhibits their production of anti-apoptotic and anti-angiogenic cytokines.
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Affiliation(s)
- Claire E Lewis
- Tumour Targeting Group, Academic Unit of Pathology, Section of Infection, Inflammation and Immunity, The Sir Henry Wellcome Laboratories for Medical Research, University of Sheffield Medical School, Beech Hill Road, Sheffield S10 2RX, UK
| | - Russell Hughes
- Tumour Targeting Group, Academic Unit of Pathology, Section of Infection, Inflammation and Immunity, The Sir Henry Wellcome Laboratories for Medical Research, University of Sheffield Medical School, Beech Hill Road, Sheffield S10 2RX, UK
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48
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Raman D, Baugher PJ, Thu YM, Richmond A. Role of chemokines in tumor growth. Cancer Lett 2007; 256:137-65. [PMID: 17629396 PMCID: PMC2065851 DOI: 10.1016/j.canlet.2007.05.013] [Citation(s) in RCA: 443] [Impact Index Per Article: 26.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2007] [Revised: 05/21/2007] [Accepted: 05/21/2007] [Indexed: 12/11/2022]
Abstract
Chemokines play a paramount role in the tumor progression. Chronic inflammation promotes tumor formation. Both tumor cells and stromal cells elaborate chemokines and cytokines. These act either by autocrine or paracrine mechanisms to sustain tumor cell growth, induce angiogenesis and facilitate evasion of immune surveillance through immunoediting. The chemokine receptor CXCR2 and its ligands promote tumor angiogenesis and leukocyte infiltration into the tumor microenvironment. In harsh acidic and hypoxic microenvironmental conditions tumor cells up-regulate their expression of CXCR4, which equips them to migrate up a gradient of CXCL12 elaborated by carcinoma-associated fibroblasts (CAFs) to a normoxic microenvironment. The CXCL12-CXCR4 axis facilitates metastasis to distant organs and the CCL21-CCR7 chemokine ligand-receptor pair favors metastasis to lymph nodes. These two chemokine ligand-receptor systems are common key mediators of tumor cell metastasis for several malignancies and as such provide key targets for chemotherapy. In this paper, the role of specific chemokines/chemokine receptor interactions in tumor progression, growth and metastasis and the role of chemokine/chemokine receptor interactions in the stromal compartment as related to angiogenesis, metastasis, and immune response to the tumor are reviewed.
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Affiliation(s)
| | | | - Yee Mon Thu
- Department of Cancer Biology, Nashville, TN 37232, USA
| | - Ann Richmond
- Department of Veterans Affairs, Nashville, TN 37232, USA
- Department of Cancer Biology, Nashville, TN 37232, USA
- Vanderbilt University School of Medicine, Nashville, TN 37232, USA
- Corresponding author Dr. Ann Richmond, Department of Cancer Biology, Vanderbilt University School of Medicine, 432 PRB, 23 Avenue South @ Pierce, Nashville, TN 37232. U.S.A. Tel. +1 615 343 7777 Fax: +1 615 936 2911 e-mail:
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49
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Zhang L, Yeger H, Das B, Irwin MS, Baruchel S. Tissue microenvironment modulates CXCR4 expression and tumor metastasis in neuroblastoma. Neoplasia 2007; 9:36-46. [PMID: 17325742 PMCID: PMC1803034 DOI: 10.1593/neo.06670] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2006] [Revised: 11/27/2006] [Accepted: 11/28/2006] [Indexed: 11/18/2022] Open
Abstract
Neuroblastoma (NB) is derived from intrinsic migratory neural crest cells and has a high potential for distant metastasis. Growing evidence has implicated chemokine receptors, especially CXCR4, which normally control immune and inflammatory cell migration, as having important roles in tumor progression. In this study, we investigated the expression of CXCR4 in eight different NB cell lines and found that CXCR4 expression is dynamically regulated in NB and can be modulated by different tissue stromata. In addition, we demonstrate that IL-5 and IFN-gamma are released from stromal cells and act as differential mediators for CXCR4 expression. We also overexpressed CXCR4 in two NB cell lines, NUB-7 and SK-N-BE(2), and studied the role of CXCR4 in NB metastasis both in vitro and in vivo. In vitro transwell invasion assay showed that CXCR4 overexpression promoted NB cell migration preferentially toward a bone marrow stromal cell-conditioned medium. Using an in vivo xenograft model, CXCR4-overexpressing cells showed an increased incidence of metastasis, most notably bone marrow metastasis. Our studies reveal critical roles for CXCR4 in NB metastasis and provide insights into the regulatory mechanism of chemokine receptors in NB and the importance of the tissue microenvironment in modulating tumor cell behavior.
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Affiliation(s)
- Libo Zhang
- New Agent and Innovative Therapy Program, The Hospital for Sick Children, Toronto, Canada
- Department of Pediatric Laboratory Medicine, The Hospital for Sick Children, Toronto, Canada
| | - Herman Yeger
- Department of Pediatric Laboratory Medicine, The Hospital for Sick Children, Toronto, Canada
| | - Bikul Das
- New Agent and Innovative Therapy Program, The Hospital for Sick Children, Toronto, Canada
- Department of Pediatric Laboratory Medicine, The Hospital for Sick Children, Toronto, Canada
| | - Meredith S Irwin
- Division of Hematology and Oncology, Department of Pediatrics, The Hospital for Sick Children, Toronto, Canada
- Institute of Medical Sciences, University of Toronto, Toronto, Canada
| | - Sylvain Baruchel
- New Agent and Innovative Therapy Program, The Hospital for Sick Children, Toronto, Canada
- Division of Hematology and Oncology, Department of Pediatrics, The Hospital for Sick Children, Toronto, Canada
- Institute of Medical Sciences, University of Toronto, Toronto, Canada
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Boström P, Magnusson B, Svensson PA, Wiklund O, Borén J, Carlsson LMS, Ståhlman M, Olofsson SO, Hultén LM. Hypoxia converts human macrophages into triglyceride-loaded foam cells. Arterioscler Thromb Vasc Biol 2006; 26:1871-6. [PMID: 16741148 DOI: 10.1161/01.atv.0000229665.78997.0b] [Citation(s) in RCA: 133] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
OBJECTIVE Atherosclerotic lesions have regions that are hypoxic. Because the lesion contains macrophages that are loaded with lipid, we investigated whether hypoxia can influence the accumulation of lipids in these cells. METHODS AND RESULTS Exposure of human macrophages to hypoxia for 24 hours resulted in an increased formation of cytosolic lipid droplets and an increased accumulation of triglycerides. Exposure of the macrophages to oxidized low-density lipoprotein (oxLDL) increased the accumulation of cytosolic lipid droplets because of an increase in cellular cholesterol esters. The accumulation of lipid droplets in oxLDL-treated cells was further increased after hypoxia, caused by an increased level of triglycerides. Expression analyses combined with immunoblot or RT-PCR demonstrated that hypoxia increased the expression of several genes that could promote the accumulation of lipid droplets. Hypoxia increased the mRNA and protein levels of adipocyte differentiation-related protein (ADRP). It is well known that an increased expression of ADRP increases the formation of lipid droplets. Hypoxia decreased the expression of enzymes involved in beta-oxidation (acyl-coenzyme A synthetase and acyl-coenzyme A dehydrogenase) and increased the expression of stearoyl-coenzyme A desaturase, an important enzyme in the fatty acid biosynthesis. Moreover, exposure to hypoxia decreased the rate of beta-oxidation, whereas the accumulation of triglycerides increased. CONCLUSIONS The results demonstrate that exposure of human macrophages to hypoxia causes an accumulation of triglyceride-containing cytosolic lipid droplets. This indicates that the hypoxia present in atherosclerotic lesions can contribute to the formation of the lipid-loaded macrophages that characterize the lesion and to the accumulation of triglycerides in such lesions.
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Affiliation(s)
- Pontus Boström
- Wallenberg Laboratory for Cardiovascular Research, Sahlgrenska Academy, Göteborg, Sweden
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