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Beadell B, Yamauchi J, Wong-Beringer A. Comparative in vitro efficacy of antibiotics against the intracellular reservoir of Staphylococcus aureus. J Antimicrob Chemother 2024:dkae241. [PMID: 39073778 DOI: 10.1093/jac/dkae241] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2024] [Accepted: 06/26/2024] [Indexed: 07/30/2024] Open
Abstract
Staphylococcus aureus (SA) is a leading cause of bloodstream infection. The liver represents the sentinel immune organ for clearance of bloodstream pathogens and eradication of intracellular SA from liver-resident macrophages (Kupffer cells, KCs) eliminates the likely pathogenic reservoir that contributes to persistent bacteraemia. OBJECTIVES We assessed antimicrobial activity at phagolysosome-mimicking pH, intracellular penetration, and SA eradication within KCs in vitro for clinically prescribed antistaphylococcal agents alone or in combination: vancomycin, daptomycin, ceftaroline, ceftobiprole, oritavancin, oxacillin, cefazolin; rifampin and fosfomycin. METHODS pH-adjusted broth microdilution assays, intracellular bioaccumulation assays, and intracellular killing assays against clinical bloodstream isolates were performed using a murine KC line with study agents. RESULTS Rifampin and β-lactams exhibited enhanced activity [2- to 16-fold minimum inhibitory concentrations (MIC) decrease] at phagolysosomal pH while vancomycin, oritavancin, daptomycin and fosfomycin demonstrated reduced activity (2- to 32-fold MIC increase in order of least to greatest potency reduction). All agents evaluated had poor to modest intracellular to extracellular concentration ratios (0.024-7.8), with exceptions of rifampin and oritavancin (intracellular to extracellular ratios of 17.4 and 78.2, respectively). Finally, we showed that the first-line treatment for SA bacteraemia (SAB), vancomycin, performed worse than all other tested antibiotics in eradicating intracellular SA at human Cmax concentration (0.20 log cfu decrease), while oritavancin performed better than all other agents alone (2.05 versus 1.06-1.36 log cfu decrease). CONCLUSIONS Our findings raise concerns about the efficacy of commonly prescribed antibiotics against intracellular SA reservoirs and emphasize the need to consider targeting pathogen eradication from the liver to achieve early control of SAB.
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Affiliation(s)
- Brent Beadell
- Alfred E. Mann School of Pharmacy and Pharmaceutical Sciences, University of Southern California, Los Angeles, CA, USA
| | - Joe Yamauchi
- Alfred E. Mann School of Pharmacy and Pharmaceutical Sciences, University of Southern California, Los Angeles, CA, USA
| | - Annie Wong-Beringer
- Alfred E. Mann School of Pharmacy and Pharmaceutical Sciences, University of Southern California, Los Angeles, CA, USA
- Department of Pharmacy, Huntington Hospital, Pasadena, CA, USA
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2
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Qin M, Huang L, Li M, Shao T, Zhang J, Jiang X, Shao C, Zhao C, Pan Y, Zhou Q, Wang Y, Liu XM, Qiu J. Immunotoxicity Evaluation of Trihalophenolic Disinfection By-Products in Mouse and Human Mononuclear Macrophage Systems: The Role of RNA Epitranscriptomic Modification in Mammalian Immunity. ENVIRONMENTAL HEALTH PERSPECTIVES 2023; 131:127023. [PMID: 38157273 PMCID: PMC10756339 DOI: 10.1289/ehp11329] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2022] [Revised: 10/15/2023] [Accepted: 11/14/2023] [Indexed: 01/03/2024]
Abstract
BACKGROUND 2,4,6-Trichlorophenol (TCP), 2,4,6-tribromophenol (TBP) and 2,4,6-triiodophenol (TIP) are three widely detected trihalophenolic disinfection by-products (DBPs). Previous studies have mainly focused on the carcinogenic risk and developmental toxicity of 2,4,6-trihalophenols. Very little is known about their immunotoxicity in mammals. OBJECTIVES We investigated the effects of 2,4,6-trihalophenols on mammalian immunity using a mouse macrophage model infected with bacteria or intracellular parasites and aimed to elucidate the underlying mechanisms from an epitranscriptomic perspective. The identified mechanisms were further validated in human peripheral blood mononuclear cells (PBMCs). METHODS The mouse macrophage cell line RAW264.7 and primary mouse peritoneal macrophages were exposed to different concentrations of TCP, TBP, and TIP. The pro-inflammatory marker Ly6C, the survival of the bacterium Escherichia coli (E. coli), and the parasite burden of Toxoplasma gondii (T. gondii) were assessed. Furthermore, the global gene expression profiling of macrophages following exposure to 2,4,6-trihalophenols was obtained through RNA-sequencing (RNA-seq). The effects of 2,4,6-trihalophenols on RNA N 6 -methyladenosine (m 6 A ) methyltransferases and total RNA m 6 A levels were evaluated using Western blotting and dot blot, respectively. Transcriptome-wide m 6 A methylome was analyzed by m 6 A -seq . In addition, expression of m 6 A regulators and total RNA m 6 A levels in human PBMCs exposed to 2,4,6-trihalophenols were detected using quantitative reverse transcriptase polymerase chain reaction and dot blot, respectively. RESULTS Mouse macrophages exposed to TCP, TBP, or TIP had lower expression of the pro-inflammatory marker Ly6C, with a greater difference from control observed for TIP-exposed cells. Consistently, macrophages exposed to such DBPs, especially TIP, were susceptible to infection with the bacterium E. coli and the intracellular parasite T. gondii, indicating a compromised ability of macrophages to defend against pathogens. Intriguingly, macrophages exposed to TIP had significantly greater m 6 A levels, which correlated with the greater expression levels of m 6 A methyltransferases. Macrophages exposed to each of the three 2,4,6-trihalophenols exhibited transcriptome-wide redistribution of m 6 A . In particular, the m 6 A peaks in genes associated with immune-related pathways were altered after exposure. In addition, differences in m 6 A were also observed in human PBMCs after exposure to 2,4,6-trihalophenols. DISCUSSION These findings suggest that 2,4,6-trihalophenol exposure impaired the ability of macrophages to defend against pathogens. This response might be associated with notable differences in m 6 A after exposure. To the best of our knowledge, this study presents the first m 6 A landscape across the transcriptome of immune cells exposed to pollutants. However, significant challenges remain in elucidating the mechanisms by which m 6 A mediates immune dysregulation in infected macrophages after 2,4,6-trihalophenol exposure. https://doi.org/10.1289/EHP11329.
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Affiliation(s)
- Min Qin
- Key Laboratory of Pathogen Biology of Jiangsu Province, Department of Pathogen Biology, Nanjing Medical University, Nanjing, Jiangsu, China
- Department of Pathology, Children’s Hospital of Nanjing Medical University, Nanjing, Jiangsu, China
| | - Linyuan Huang
- School of Life Science and Technology, China Pharmaceutical University, Nanjing, Jiangsu, China
- School of Pharmacy, Jiangsu Health Vocational College, Nanjing, Jiangsu, China
| | - Meishuang Li
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, Jiangsu, China
| | - Tianye Shao
- Key Laboratory of Pathogen Biology of Jiangsu Province, Department of Pathogen Biology, Nanjing Medical University, Nanjing, Jiangsu, China
| | - Jun Zhang
- School of Life Science and Technology, China Pharmaceutical University, Nanjing, Jiangsu, China
| | - Xiaoqin Jiang
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, Jiangsu, China
| | - Chenlu Shao
- Key Laboratory of Pathogen Biology of Jiangsu Province, Department of Pathogen Biology, Nanjing Medical University, Nanjing, Jiangsu, China
| | - Chengsi Zhao
- Key Laboratory of Pathogen Biology of Jiangsu Province, Department of Pathogen Biology, Nanjing Medical University, Nanjing, Jiangsu, China
| | - Yang Pan
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, Jiangsu, China
| | - Qing Zhou
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, Jiangsu, China
| | - Yong Wang
- Key Laboratory of Pathogen Biology of Jiangsu Province, Department of Pathogen Biology, Nanjing Medical University, Nanjing, Jiangsu, China
| | - Xiao-Min Liu
- School of Life Science and Technology, China Pharmaceutical University, Nanjing, Jiangsu, China
| | - Jingfan Qiu
- Key Laboratory of Pathogen Biology of Jiangsu Province, Department of Pathogen Biology, Nanjing Medical University, Nanjing, Jiangsu, China
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3
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Optimization of Capture ELISAs for Chicken Cytokines Using Commercially Available Antibodies. Animals (Basel) 2022; 12:ani12213040. [PMID: 36359163 PMCID: PMC9658146 DOI: 10.3390/ani12213040] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2022] [Revised: 10/28/2022] [Accepted: 10/31/2022] [Indexed: 11/09/2022] Open
Abstract
Cytokines like interferon (IFN)-γ, interleukin (IL)-2, IL-6, IL-10, and IL-12p40 are important biomarkers for characterizing the nature and strength of immune responses. It is important to be able to quantify the cytokines at the protein level in biological samples. Quantification of chicken cytokines is generally performed on the level of messenger RNA (mRNA) by quantitative polymerase chain reaction (qPCR) because very few capture ELISAs for the quantification of chicken cytokine proteins are commercially available. Here, we describe the optimization and validation of capture ELISAs for chicken IL-2, IL-6, IL-10, IL-12p40, and IFN-γ using commercially available antibodies and reagents. First, we determined the optimal concentrations of the antibodies. We then verified the ELISAs’ performance and established that the lower limit of detection (LLOD) for all cytokines was below 32 pg/mL. The ELISAs show the same binding characteristics for recombinant and native cytokines (parallelism was <15.2% CV). Values for inter-assay variation were consistently low and mostly <20% CV. Overall, the optimized capture ELISAs are sensitive (<32 pg/mL) and reliable tools to quantify chicken cytokines. These ELISAs can easily and inexpensively be utilized in any immunological lab and may therefore have wide applicability in immunological research for poultry.
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Tasnim F, Huang X, Lee CZW, Ginhoux F, Yu H. Recent Advances in Models of Immune-Mediated Drug-Induced Liver Injury. FRONTIERS IN TOXICOLOGY 2022; 3:605392. [PMID: 35295156 PMCID: PMC8915912 DOI: 10.3389/ftox.2021.605392] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2020] [Accepted: 03/30/2021] [Indexed: 12/12/2022] Open
Abstract
Hepatic inflammation is a key feature of a variety of liver diseases including drug-induced liver injury (DILI), orchestrated by the innate immune response (Kupffer cells, monocytes, neutrophils, dendritic cells) and the adaptive immune system (T cells and natural killer T cells). In contrast to acute DILI, prediction of immune-mediated DILI (im-DILI) has been more challenging due to complex disease pathogenesis, lack of reliable models and limited knowledge of underlying mechanisms. This review summarizes in vivo and in vitro systems that have been used to model im-DILI. In particular, the review focuses on state-of-the-art in vitro human-based multicellular models which have been developed to supplement the use of in vivo models due to interspecies variation and increasing ethical concerns regarding animal use. Advantages of the co-cultures in maintaining hepatocyte functions and importantly, introducing heterotypic cell-cell interactions to mimic inflammatory hepatic microenvironment are discussed. Challenges regarding cell source and incorporation of different cells with physical cell-cell contact are outlined and potential solutions are proposed. It is likely that better understanding of the interplay of immune cells in liver models will allow for the development of more accurate systems to better predict hepatotoxicity and stratification of drugs that can cause immune-mediated effects.
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Affiliation(s)
- Farah Tasnim
- Innovations in Food & Chemical Safety Programme, ASTAR, Singapore, Singapore.,Institute of Bioengineering and Nanotechnology, The Nanos, Singapore, Singapore
| | - Xiaozhong Huang
- Innovations in Food & Chemical Safety Programme, ASTAR, Singapore, Singapore.,Institute of Bioengineering and Nanotechnology, The Nanos, Singapore, Singapore.,Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Christopher Zhe Wei Lee
- Innovations in Food & Chemical Safety Programme, ASTAR, Singapore, Singapore.,Singapore Immunology Network, Singapore, Singapore.,School of Biological Sciences, Nanyang Technological University, Singapore, Singapore
| | - Florent Ginhoux
- Innovations in Food & Chemical Safety Programme, ASTAR, Singapore, Singapore.,Singapore Immunology Network, Singapore, Singapore.,School of Biological Sciences, Nanyang Technological University, Singapore, Singapore.,Shanghai Institute of Immunology, Shanghai JiaoTong University School of Medicine, Shanghai, China.,Translational Immunology Institute, SingHealth Duke-NUS Academic Medical Centre, Singapore, Singapore
| | - Hanry Yu
- Innovations in Food & Chemical Safety Programme, ASTAR, Singapore, Singapore.,Institute of Bioengineering and Nanotechnology, The Nanos, Singapore, Singapore.,Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore.,National University of Singapore (NUS) Graduate School for Integrative Sciences and Engineering, Centre for Life Sciences, Singapore, Singapore.,T-Labs, Mechanobiology Institute, Singapore, Singapore.,Critical Analytics for Manufacturing Personalised-Medicine Interdisciplinary Research Groups (CAMP-IRG), Singapore-Massachusetts Institute of Technology Alliance for Research and Technology, Singapore, Singapore
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Zulfiqar B, Avery VM. Assay development in leishmaniasis drug discovery: a comprehensive review. Expert Opin Drug Discov 2021; 17:151-166. [PMID: 34818139 DOI: 10.1080/17460441.2022.2002843] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
INTRODUCTION Cutaneous, muco-cutaneous and visceral leishmaniasis occur due to an infection with the protozoan parasite Leishmania. The current therapeutic options are limited mainly due to extensive toxicity, emerging resistance and variation in efficacy based on species and strain of the Leishmania parasite. There exists a high unmet medical need to identify new chemical starting points for drug discovery to tackle the disease. AREAS COVERED The authors have highlighted the recent progress, limitations and successes achieved in assay development for leishmaniasis drug discovery. EXPERT OPINION It is true that sophisticated and robust phenotypic in vitro assays have been developed during the last decade, however limitations and challenges remain with respect to variation in activity reported between different research groups and success in translating in vitro outcomes in vivo. The variability is not only due to strain and species differences but also a lack of well-defined criteria and assay conditions, e.g. culture media, host cell type, assay formats, parasite form used, multiplicity of infection and incubation periods. Thus, there is an urgent need for more physiologically relevant assays that encompass multi-species phenotypic approaches to identify new chemical starting points for leishmaniasis drug discovery.
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Affiliation(s)
- Bilal Zulfiqar
- Discovery Biology, Griffith University, Brisbane, Australia
| | - Vicky M Avery
- Discovery Biology, Griffith University, Brisbane, Australia.,Discovery Biology, Griffith University Drug Discovery Programme for Cancer Therapeutics, Brisbane, Australia.,School of Environment and Sciences, Griffith University, Brisbane, Australia
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Khatun M, Damgaard BM, Andersen JB, Røntved CM. Effect of polymyxin B on ex vivo tumor necrosis factor-alpha responsiveness of blood leukocytes in Danish Holstein Friesian cows. Vet Immunol Immunopathol 2021; 238:110293. [PMID: 34284224 DOI: 10.1016/j.vetimm.2021.110293] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Revised: 07/14/2021] [Accepted: 07/14/2021] [Indexed: 10/20/2022]
Abstract
Whole blood stimulation assay (WBA) with killed gram-positive and gram-negative udder pathogens were used to investigate the interference of the endotoxin-binding antibiotic polymyxin B (PMB) on the ex vivo TNF-α response. Blood samples were collected from first to third lactating dairy cows in their early lactation (<50 days in milk, n = 32) period. The WBA was stimulated with both inactivated bacteria (e.g., dead Escherichia coli, Staphylococcus aureus, Streptococcus dysgalactiae, Streptococcus uberis), at a concentration of 2.5 × 106/mL; and pathogen-associated molecular pattern molecules, namely E. coli LPS (10 μg/mL), and S. aureus peptidoglycan (PG, 10 μg/mL). The PMB was added at a concentration of 0, 12.5, 25, 50, 100, and 200 μg/mL to each stimulant, respectively. All bacteria stimulants resulted in an increased TNF-α response compared to the negative control. The PMB affected the TNF-α responses of gram-positive (except S. dysgalactaie), gram-negative bacteria; and bacterial cell wall components at a PMB concentration of 25-50 μg/mL. The LPS and E. coli had similar TNF-α response but PG had a lower TNF-α response than gram-positive bacteria. The doses of PMB (≥ 25 μg/mL) should be used with caution when using different types of pathogens or should be avoided in ex vivo TNF-α studies.
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Affiliation(s)
- Momena Khatun
- Aarhus University, Faculty of Science and Technology, Department of Animal Science, Blichers Allé 20, P.O. Box 50, DK-8300, Tjele, Denmark.
| | - Birthe M Damgaard
- Aarhus University, Faculty of Science and Technology, Department of Animal Science, Blichers Allé 20, P.O. Box 50, DK-8300, Tjele, Denmark.
| | - Jens B Andersen
- Aarhus University, Faculty of Science and Technology, Department of Animal Science, Blichers Allé 20, P.O. Box 50, DK-8300, Tjele, Denmark.
| | - Christine M Røntved
- Aarhus University, Faculty of Science and Technology, Department of Animal Science, Blichers Allé 20, P.O. Box 50, DK-8300, Tjele, Denmark; Christine Røntved, CMR On-Site RD, Graverhusvej 53, Langholt, 9310, Vodskov, Denmark.
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7
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Viegas C, Caetano LA, Cox J, Korkalainen M, Haines SR, Dannemiller KC, Viegas S, Reponen T. The effects of waste sorting in environmental microbiome, THP-1 cell viability and inflammatory responses. ENVIRONMENTAL RESEARCH 2020; 185:109450. [PMID: 32244107 DOI: 10.1016/j.envres.2020.109450] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2020] [Revised: 02/28/2020] [Accepted: 03/25/2020] [Indexed: 06/11/2023]
Abstract
Workers in the waste sorting industry are exposed to diverse bioaerosols. Characterization of these bioaerosols is necessary to more accurately assess the health risks of exposure. The use of high-throughput DNA sequencing for improved analysis of microbial composition of bioaerosols, in combination with their in vitro study in relevant cell cultures, represents an important opportunity to find answers on the biological effects of bioaerosols. This study aimed to characterize by high-throughput sequencing the biodiversity present in complex aerosol mixtures retained in forklift air conditioning filters of a waste-sorting industry and its effects on cytotoxicity and secretion of proinflammatory cytokines in vitro using human macrophages derived from monocytic THP-1 cells. Seventeen filters from the filtration system from forklifts operating in one waste sorting facility and one control filter (similar filter without prior use) were analyzed using high-throughput sequencing and toxicological tests in vitro. A trend of positive correlation was seen between the number of bacterial and fungal OTUs (r = 0.47, p = 0.06). Seven filters (39%) exhibited low or moderate cytotoxicity (p < 0.05). The highest cytotoxic responses had a reduction in cell viability between 17 and 22%. Filter samples evoked proinflammatory responses, especially the production of TNFα. No significant correlation was found between fungal richness and inflammatory responses in vitro. The data obtained stress the need of thorough exposure assessment in waste-sorting industry and to take immunomodulatory properties into consideration for bioaerosols hazard characterization. The broad spectrum of microbial contamination detected in this study demonstrates that adequate monitoring of bioaerosol exposure is necessary to evaluate and minimize risks. The combined techniques can support the implementation of effective environmental monitoring programs of public and occupational health importance.
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Affiliation(s)
- C Viegas
- H&TRC- Health & Technology Research Center, ESTeSL- Escola Superior de Tecnologia da Saúde, Instituto Politécnico de Lisboa, Portugal; NOVA National School of Public Health, Public Health Research Centre, Universidade NOVA de Lisboa, Portugal; Comprehensive Health Research Center (CHRC), Portugal.
| | - L A Caetano
- H&TRC- Health & Technology Research Center, ESTeSL- Escola Superior de Tecnologia da Saúde, Instituto Politécnico de Lisboa, Portugal; Research Institute for Medicines (iMed.ULisboa), Faculty of Pharmacy, University of Lisbon, 649-003, Lisbon, Portugal
| | - J Cox
- Department of Environmental Health, University of Cincinnati, P.O. Box 670056, Cincinnati, OH, 45242, USA
| | - M Korkalainen
- Finnish Institute for Health and Welfare (THL), Environmental Health, P.O. Box 95, FIN-70701, Kuopio, Finland
| | - S R Haines
- Department of Civil, Environmental, and Geodetic Engineering, College of Engineering, The Ohio State University, Columbus, OH, USA; Division of Environmental Health Sciences, College of Public Health, The Ohio State University, Columbus, OH, USA; Environmental Science Graduate Program, The Ohio State University, Columbus, OH, USA
| | - K C Dannemiller
- Department of Civil, Environmental, and Geodetic Engineering, College of Engineering, The Ohio State University, Columbus, OH, USA; Division of Environmental Health Sciences, College of Public Health, The Ohio State University, Columbus, OH, USA
| | - S Viegas
- H&TRC- Health & Technology Research Center, ESTeSL- Escola Superior de Tecnologia da Saúde, Instituto Politécnico de Lisboa, Portugal; NOVA National School of Public Health, Public Health Research Centre, Universidade NOVA de Lisboa, Portugal; Comprehensive Health Research Center (CHRC), Portugal
| | - T Reponen
- Department of Environmental Health, University of Cincinnati, P.O. Box 670056, Cincinnati, OH, 45242, USA
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Sullivan C, Brown NE, Vasiliauskas J, Pathrose P, Starnes SL, Waltz SE. Prostate Epithelial RON Signaling Promotes M2 Macrophage Activation to Drive Prostate Tumor Growth and Progression. Mol Cancer Res 2020; 18:1244-1254. [PMID: 32439702 DOI: 10.1158/1541-7786.mcr-20-0060] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2020] [Revised: 04/11/2020] [Accepted: 05/18/2020] [Indexed: 12/31/2022]
Abstract
Effective treatment of advanced prostate cancer persists as a significant clinical need as only 30% of patients with distant disease survive to 5 years after diagnosis. Targeting signaling and tumor cell-immune cell interactions in the tumor microenvironment has led to the development of powerful immunotherapeutic agents, however, the prostate tumor milieu remains impermeable to these strategies highlighting the need for novel therapeutic targets. In this study, we provide compelling evidence to support the role of the RON receptor tyrosine kinase as a major regulator of macrophages in the prostate tumor microenvironment. We show that loss of RON selectively in prostate epithelial cells leads to significantly reduced prostate tumor growth and metastasis and is associated with increased intratumor infiltration of macrophages. We further demonstrate that prostate epithelial RON loss induces transcriptional reprogramming of macrophages to support expression of classical M1 markers and suppress expression of alternative M2 markers. Interestingly, our results show epithelial RON activation drives upregulation of RON expression in macrophages as a positive feed-forward mechanism to support prostate tumor growth. Using 3D coculture assays, we provide additional evidence that epithelial RON expression coordinates interactions between prostate tumor cells and macrophages to promote macrophage-mediated tumor cell growth. Taken together, our results suggest that RON receptor signaling in prostate tumor cells directs the functions of macrophages in the prostate tumor microenvironment to promote prostate cancer. IMPLICATIONS: Epithelial RON is a novel immunotherapeutic target that is responsible for directing the macrophage antitumor immune response to support prostate tumor growth and progression.
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Affiliation(s)
- Camille Sullivan
- Department of Cancer Biology, University of Cincinnati College of Medicine, Cincinnati, Ohio
| | - Nicholas E Brown
- Department of Cancer Biology, University of Cincinnati College of Medicine, Cincinnati, Ohio
| | - Juozas Vasiliauskas
- Department of Cancer Biology, University of Cincinnati College of Medicine, Cincinnati, Ohio
| | - Peterson Pathrose
- Department of Surgery, University of Cincinnati College of Medicine, Cincinnati, Ohio
| | - Sandra L Starnes
- Department of Surgery, University of Cincinnati College of Medicine, Cincinnati, Ohio
| | - Susan E Waltz
- Department of Cancer Biology, University of Cincinnati College of Medicine, Cincinnati, Ohio.
- Research Service, Cincinnati Veterans Affairs Medical Center, Cincinnati, Ohio
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