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Paris A, Tardif N, Baietti FM, Berra C, Leclair HM, Leucci E, Galibert M, Corre S. The AhR-SRC axis as a therapeutic vulnerability in BRAFi-resistant melanoma. EMBO Mol Med 2022; 14:e15677. [PMID: 36305167 PMCID: PMC9728058 DOI: 10.15252/emmm.202215677] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2022] [Revised: 09/30/2022] [Accepted: 09/30/2022] [Indexed: 12/14/2022] Open
Abstract
The nongenetic mechanisms required to control tumor phenotypic plasticity and shape drug-resistance remain unclear. We show here that the Aryl hydrocarbon Receptor (AhR) transcription factor directly regulates the gene expression program associated with the acquisition of resistance to BRAF inhibitor (BRAFi) in melanoma. In addition, we show in melanoma cells that canonical activation of AhR mediates the activation of the SRC pathway and promotes the acquisition of an invasive and aggressive resistant phenotype to front-line BRAFi treatment in melanoma. This nongenetic reprogramming identifies a clinically compatible approach to reverse BRAFi resistance in melanoma. Using a preclinical BRAFi-resistant PDX melanoma model, we demonstrate that SRC inhibition with dasatinib significantly re-sensitizes melanoma cells to BRAFi. Together we identify the AhR/SRC axis as a new therapeutic vulnerability to trigger resistance and warrant the introduction of SRC inhibitors during the course of the treatment in combination with front-line therapeutics to delay BRAFi resistance.
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Affiliation(s)
- Anaïs Paris
- Univ Rennes, CNRS, INSERM, IGDR (Institut de Génétique et Développement de Rennes) – UMR6290, ERL U1305RennesFrance
| | - Nina Tardif
- Univ Rennes, CNRS, INSERM, IGDR (Institut de Génétique et Développement de Rennes) – UMR6290, ERL U1305RennesFrance
| | - Francesca M Baietti
- Laboratory for RNA Cancer Biology, Department of OncologyLKI, KU LeuvenLeuvenBelgium,Trace PDX Platform, Department of OncologyLKI, KU LeuvenLeuvenBelgium
| | - Cyrille Berra
- Univ Rennes, CNRS, INSERM, IGDR (Institut de Génétique et Développement de Rennes) – UMR6290, ERL U1305RennesFrance,Department of Molecular Genetics and GenomicsHospital University of Rennes (CHU Rennes)RennesFrance
| | - Héloïse M Leclair
- Univ Rennes, CNRS, INSERM, IGDR (Institut de Génétique et Développement de Rennes) – UMR6290, ERL U1305RennesFrance
| | - Eleonora Leucci
- Laboratory for RNA Cancer Biology, Department of OncologyLKI, KU LeuvenLeuvenBelgium,Trace PDX Platform, Department of OncologyLKI, KU LeuvenLeuvenBelgium
| | - Marie‐Dominique Galibert
- Univ Rennes, CNRS, INSERM, IGDR (Institut de Génétique et Développement de Rennes) – UMR6290, ERL U1305RennesFrance,Department of Molecular Genetics and GenomicsHospital University of Rennes (CHU Rennes)RennesFrance
| | - Sébastien Corre
- Univ Rennes, CNRS, INSERM, IGDR (Institut de Génétique et Développement de Rennes) – UMR6290, ERL U1305RennesFrance
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2
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The aryl hydrocarbon receptor promotes differentiation during mouse preimplantational embryo development. Stem Cell Reports 2021; 16:2351-2363. [PMID: 34478649 PMCID: PMC8452532 DOI: 10.1016/j.stemcr.2021.08.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2020] [Revised: 08/04/2021] [Accepted: 08/04/2021] [Indexed: 12/17/2022] Open
Abstract
Mammalian embryogenesis is a complex process controlled by transcription factors that regulate the balance between pluripotency and differentiation. Transcription factor aryl hydrocarbon receptor (AhR) regulates OCT4/POU5F1 and NANOG, both essential controllers of pluripotency, stemness and early embryo development. Molecular mechanisms controlling OCT4/POU5F1 and NANOG during embryogenesis remain unidentified. We show that AhR regulates pluripotency factors and maintains the metabolic activity required for proper embryo differentiation. AhR-lacking embryos (AhR−/−) showed a pluripotent phenotype characterized by a delayed expression of trophectoderm differentiation markers. Accordingly, central pluripotency factors OCT4/POU5F1 and NANOG were overexpressed in AhR−/− embryos at initial developmental stages. An altered intracellular localization of these factors was observed in the absence of AhR and, importantly, Oct4 had an opposite expression pattern with respect to AhR from the two-cell stage to blastocyst, suggesting a negative regulation of OCT4/POU5F by AhR. We propose that AhR is a regulator of pluripotency and differentiation in early mouse embryogenesis. AhR regulates pluripotency factors OCT4 and NANOG during early embryo differentiation AhR lacking embryos (AhR−/−) show a pluripotent phenotype Pluripotent phenotype of AhR−/− embryos show enhanced glycolytic metabolism
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3
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Fujisawa N, Yoshioka W, Yanagisawa H, Tohyama C. Significance of AHR nuclear translocation sequence in 2,3,7,8-tetrachlorodibenzo-p-dioxin-induced cPLA 2α activation and hydronephrosis. Arch Toxicol 2019; 93:1255-1264. [PMID: 30790002 DOI: 10.1007/s00204-019-02414-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2018] [Accepted: 02/14/2019] [Indexed: 12/13/2022]
Abstract
The aryl hydrocarbon receptor (AHR) plays a major role in 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)-induced toxicity phenotypes. TCDD bound to AHR elicits both genomic action in which target genes are transcriptionally upregulated and nongenomic action in which cytosolic phospholipase A2α (cPLA2α) is rapidly activated. However, how either of these actions, separately or in combination, induces toxicity phenotypes is largely unknown. In this study, we used AHRnls/nls mice as a model in which AHR was mutated to lack nuclear translocation sequence (NLS), and AHRd/- mice as the corresponding control. Using this model, we studied TCDD-induced alterations in cPLA2α activation and related factors because of the pivotal roles of cPLA2α both in AHR's nongenomic action and in regulation of causative genes of TCDD-induced hydronephrosis. Dams were orally administered TCDD at a dose of 300 µg/kg body weight on postnatal day 1, and pups subsequently exposed to TCDD via milk were examined for gene expression on PND 7 and for histological changes on PND 14. The activation of the AHR genomic action and hydronephrosis onset were observed in the control group but not in the AHRnls/nls group. An ex vivo experiment using peritoneal macrophages exposed to 100 nM TCDD resulted in rapid activation of cPLA2α, an indicator of the nongenomic action, only in the control group but not in the AHRnls/nls group. These results indicated that an NLS is required for the AHR's genomic and nongenomic actions.
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Affiliation(s)
- Nozomi Fujisawa
- Laboratory of Environmental Health Sciences, Center for Disease Biology and Integrative Medicine, Graduate School of Medicine, The University of Tokyo, Tokyo, 113-0033, Japan
| | - Wataru Yoshioka
- Laboratory of Environmental Health Sciences, Center for Disease Biology and Integrative Medicine, Graduate School of Medicine, The University of Tokyo, Tokyo, 113-0033, Japan. .,Department of Public Health and Environmental Medicine, The Jikei University School of Medicine, Tokyo, 105-8461, Japan.
| | - Hiroyuki Yanagisawa
- Department of Public Health and Environmental Medicine, The Jikei University School of Medicine, Tokyo, 105-8461, Japan
| | - Chiharu Tohyama
- Laboratory of Environmental Health Sciences, Center for Disease Biology and Integrative Medicine, Graduate School of Medicine, The University of Tokyo, Tokyo, 113-0033, Japan. .,Faculty of Medicine, University of Tsukuba, Tsukuba, 305-8575, Japan.
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4
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Dong X, Luo Z, Liu T, Chai J, Ke Q, Shen L. Identification of Integrin β1 as a Novel PAG1-Interacting Protein Involved in the Inherent Radioresistance of Human Laryngeal Carcinoma. J Cancer 2018; 9:4128-4138. [PMID: 30519312 PMCID: PMC6277618 DOI: 10.7150/jca.26885] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2018] [Accepted: 08/19/2018] [Indexed: 12/22/2022] Open
Abstract
Inherent radioresistance plays a crucial role in the failure of radiotherapy. Using the inherent radioresistant (Hep-2max) and radiosensitive (Hep-2min) cell lines established from the parental cell line Hep-2, we previously reported that phosphoprotein associated with glycosphingolipid-enriched microdomains 1(PAG1) overexpression in laryngeal carcinoma cells was correlated with inherent radioresistant phenotypes. However, the underlying mechanisms of this effect remain unknown. In the present study, we performed a proteomic screen to investigate the interactome of PAG1 in Hep-2max cells resulting in the identification of several interaction partners. Bioinformatic analysis and immunofluorescence experiments indicated the integrin β1 to be a crucial interaction partner of PAG1. PAG1 was also highly expressed in laryngeal carcinoma radioresistant tissues and showed co-localization with integrin β1. In addition, we demonstrated that integrin β1's binding to PAG1 could be interrupted by MβCD, an inhibitor of lipid rafts formation. Moreover, knockdown of integrin β1 by RNA interference sensitized radioresistant cells to irradiation. Importantly, we identified 2 potential interaction sites (Pro216-Arg232 and Asn356-Gly377) in the cytoplasmic domain of PAG1 using high throughput peptide arrays. Taken together, these results suggest that the binding of PAG1 to integrin β1 in lipid rafts is essential for inherent radioresistance of human laryngeal carcinoma.
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Affiliation(s)
- Xiaoxia Dong
- Department of pharmacology, School of Basic Medical Sciences, Hubei University of Medicine, Shiyan, Hubei 442000, P.R. China
| | - Zhiguo Luo
- Department of Clinical Oncology, Taihe Hospital, Hubei University of Medicine, Shiyan, Hubei 442000, P.R. China
| | - Tiantian Liu
- Department of Clinical Oncology, Taihe Hospital, Hubei University of Medicine, Shiyan, Hubei 442000, P.R. China
| | - Jingjing Chai
- Department of Clinical Oncology, Taihe Hospital, Hubei University of Medicine, Shiyan, Hubei 442000, P.R. China
| | - Qing Ke
- Department of Clinical Oncology, Taihe Hospital, Hubei University of Medicine, Shiyan, Hubei 442000, P.R. China
| | - Li Shen
- Department of Clinical Oncology, Taihe Hospital, Hubei University of Medicine, Shiyan, Hubei 442000, P.R. China
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5
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Zhu J, Luo L, Tian L, Yin S, Ma X, Cheng S, Tang W, Yu J, Ma W, Zhou X, Fan X, Yang X, Yan J, Xu X, Lv C, Liang H. Aryl Hydrocarbon Receptor Promotes IL-10 Expression in Inflammatory Macrophages Through Src-STAT3 Signaling Pathway. Front Immunol 2018; 9:2033. [PMID: 30283437 PMCID: PMC6156150 DOI: 10.3389/fimmu.2018.02033] [Citation(s) in RCA: 102] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2018] [Accepted: 08/17/2018] [Indexed: 12/16/2022] Open
Abstract
The aryl hydrocarbon receptor (AhR) is an important immune regulator with a role in inflammatory response. However, the role of AhR in IL-10 production by inflammatory macrophages is currently unknown. In this study, we investigated LPS-induced IL-10 expression in macrophages from AhR-KO mice and AhR-overexpressing RAW264.7 cells. AhR was highly expressed after LPS stimulation through NF-κB pathway. Loss of AhR resulted in reduced IL-10 expression in LPS-induced macrophages. Moreover, the IL-10 expression was elevated in LPS-induced AhR-overexpressing RAW264.7 cells. Maximal IL-10 expression was dependent on an AhR non-genomic pathway closely related to Src and STAT3. Furthermore, AhR-associated Src activity was responsible for tyrosine phosphorylation of STAT3 and IL-10 expression by inflammatory macrophages. Adoptive transfer of AhR-expressing macrophages protected mice against LPS-induced peritonitis associated with high IL-10 production. In conclusion, we identified the AhR-Src-STAT3-IL-10 signaling pathway as a critical pathway in the immune regulation of inflammatory macrophages, It suggests that AhR may be a potential therapeutic target in immune response.
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Affiliation(s)
- Junyu Zhu
- State Key Laboratory of Trauma, Burns and Combined Injury, Research Institute of Surgery, Daping Hospital, Army Medical University, Chongqing, China
| | - Li Luo
- State Key Laboratory of Trauma, Burns and Combined Injury, Research Institute of Surgery, Daping Hospital, Army Medical University, Chongqing, China
| | - Lixing Tian
- State Key Laboratory of Trauma, Burns and Combined Injury, Research Institute of Surgery, Daping Hospital, Army Medical University, Chongqing, China
| | - Shangqi Yin
- State Key Laboratory of Trauma, Burns and Combined Injury, Research Institute of Surgery, Daping Hospital, Army Medical University, Chongqing, China
| | - Xiaoyuan Ma
- State Key Laboratory of Trauma, Burns and Combined Injury, Research Institute of Surgery, Daping Hospital, Army Medical University, Chongqing, China.,Emergency and Trauma College of Hainan Medical University, Second Affiliated Hospital of Hainan Medical University, Haikou, China
| | - Shaowen Cheng
- Trauma Center, First Affiliated Hospital of Hainan Medical University, Haikou, China
| | - Wanqi Tang
- State Key Laboratory of Trauma, Burns and Combined Injury, Research Institute of Surgery, Daping Hospital, Army Medical University, Chongqing, China
| | - Jing Yu
- State Key Laboratory of Trauma, Burns and Combined Injury, Research Institute of Surgery, Daping Hospital, Army Medical University, Chongqing, China
| | - Wei Ma
- State Key Laboratory of Trauma, Burns and Combined Injury, Research Institute of Surgery, Daping Hospital, Army Medical University, Chongqing, China
| | - Xiaoying Zhou
- State Key Laboratory of Trauma, Burns and Combined Injury, Research Institute of Surgery, Daping Hospital, Army Medical University, Chongqing, China
| | - Xia Fan
- State Key Laboratory of Trauma, Burns and Combined Injury, Research Institute of Surgery, Daping Hospital, Army Medical University, Chongqing, China
| | - Xue Yang
- State Key Laboratory of Trauma, Burns and Combined Injury, Research Institute of Surgery, Daping Hospital, Army Medical University, Chongqing, China
| | - Jun Yan
- State Key Laboratory of Trauma, Burns and Combined Injury, Research Institute of Surgery, Daping Hospital, Army Medical University, Chongqing, China
| | - Xiang Xu
- State Key Laboratory of Trauma, Burns and Combined Injury, Research Institute of Surgery, Daping Hospital, Army Medical University, Chongqing, China
| | - Chuanzhu Lv
- Emergency and Trauma College of Hainan Medical University, Second Affiliated Hospital of Hainan Medical University, Haikou, China
| | - Huaping Liang
- State Key Laboratory of Trauma, Burns and Combined Injury, Research Institute of Surgery, Daping Hospital, Army Medical University, Chongqing, China
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6
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Shen L, Ke Q, Chai J, Zhang C, Qiu L, Peng F, Deng X, Luo Z. PAG1 promotes the inherent radioresistance of laryngeal cancer cells via activation of STAT3. Exp Cell Res 2018; 370:127-136. [DOI: 10.1016/j.yexcr.2018.06.014] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2018] [Revised: 06/06/2018] [Accepted: 06/14/2018] [Indexed: 12/29/2022]
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7
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Moreno-Marín N, Merino JM, Alvarez-Barrientos A, Patel DP, Takahashi S, González-Sancho JM, Gandolfo P, Rios RM, Muñoz A, Gonzalez FJ, Fernández-Salguero PM. Aryl Hydrocarbon Receptor Promotes Liver Polyploidization and Inhibits PI3K, ERK, and Wnt/β-Catenin Signaling. iScience 2018; 4:44-63. [PMID: 30240752 PMCID: PMC6147018 DOI: 10.1016/j.isci.2018.05.006] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2017] [Revised: 04/25/2018] [Accepted: 05/09/2018] [Indexed: 01/02/2023] Open
Abstract
Aryl hydrocarbon receptor (AhR) deficiency alters tissue homeostasis. However, how AhR regulates organ maturation and differentiation remains mostly unknown. Liver differentiation entails a polyploidization process fundamental for cell growth, metabolism, and stress responses. Here, we report that AhR regulates polyploidization during the preweaning-to-adult mouse liver maturation. Preweaning AhR-null (AhR−/−) livers had smaller hepatocytes, hypercellularity, altered cell cycle regulation, and enhanced proliferation. Those phenotypes persisted in adult AhR−/− mice and correlated with compromised polyploidy, predominance of diploid hepatocytes, and enlarged centrosomes. Phosphatidylinositol-3-phosphate kinase (PI3K), extracellular signal-regulated kinase (ERK), and Wnt/β-catenin signaling remained upregulated from preweaning to adult AhR-null liver, likely increasing mammalian target of rapamycin (mTOR) activation. Metabolomics revealed the deregulation of mitochondrial oxidative phosphorylation intermediates succinate and fumarate in AhR−/− liver. Consistently, PI3K, ERK, and Wnt/β-catenin inhibition partially rescued polyploidy in AhR−/− mice. Thus, AhR may integrate survival, proliferation, and metabolism for liver polyploidization. Since tumor cells tend to be polyploid, AhR modulation could have therapeutic value in the liver. AhR is required for liver polyploidization during preweaning-to-adult transition INS-R/PI3K/AKT, ERK, Wnt/β-Cat and mTOR are downregulated during liver polyploidization Reduced polyploidy relates with enhanced mitochondrial metabolism in AhR-null liver Understanding how AhR modulates polyploidy may provide strategies against cancer
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Affiliation(s)
- Nuria Moreno-Marín
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias, Universidad de Extremadura, Badajoz, Badajoz 06071, Spain
| | - Jaime M Merino
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias, Universidad de Extremadura, Badajoz, Badajoz 06071, Spain
| | - Alberto Alvarez-Barrientos
- Servicio de Técnicas Aplicadas a las Biociencias (STAB), Universidad de Extremadura, Badajoz, Badajoz 06071, Spain
| | - Daxeshkumar P Patel
- Laboratory of Metabolism, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Shogo Takahashi
- Laboratory of Metabolism, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - José M González-Sancho
- Instituto de Investigaciones Biomédicas "Alberto Sols", Consejo Superior de Investigaciones Científicas - Universidad Autónoma de Madrid, and CIBER de Cáncer (CIBERONC), Instituto de Salud Carlos III, Madrid 28029, Spain
| | - Pablo Gandolfo
- Cell Signaling Department, CABIMER-CSIC, Sevilla 41092, Spain
| | - Rosa M Rios
- Cell Signaling Department, CABIMER-CSIC, Sevilla 41092, Spain
| | - Alberto Muñoz
- Instituto de Investigaciones Biomédicas "Alberto Sols", Consejo Superior de Investigaciones Científicas - Universidad Autónoma de Madrid, and CIBER de Cáncer (CIBERONC), Instituto de Salud Carlos III, Madrid 28029, Spain
| | - Frank J Gonzalez
- Laboratory of Metabolism, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Pedro M Fernández-Salguero
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias, Universidad de Extremadura, Badajoz, Badajoz 06071, Spain.
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8
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Rico-Leo EM, Moreno-Marín N, González-Rico FJ, Barrasa E, Ortega-Ferrusola C, Martín-Muñoz P, Sánchez-Guardado LO, Llano E, Alvarez-Barrientos A, Infante-Campos A, Catalina-Fernández I, Hidalgo-Sánchez M, de Rooij DG, Pendás AM, Peña FJ, Merino JM, Fernández-Salguero PM. piRNA-associated proteins and retrotransposons are differentially expressed in murine testis and ovary of aryl hydrocarbon receptor deficient mice. Open Biol 2017; 6:rsob.160186. [PMID: 28003471 PMCID: PMC5204120 DOI: 10.1098/rsob.160186] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2016] [Accepted: 11/14/2016] [Indexed: 11/22/2022] Open
Abstract
Previous studies suggested that the aryl hydrocarbon receptor (AhR) contributes to mice reproduction and fertility. However, the mechanisms involved remain mostly unknown. Retrotransposon silencing by Piwi-interacting RNAs (piRNAs) is essential for germ cell maturation and, remarkably, AhR has been identified as a regulator of murine B1-SINE retrotransposons. Here, using littermate AhR+/+ and AhR−/− mice, we report that AhR regulates the general course of spermatogenesis and oogenesis by a mechanism likely to be associated with piRNA-associated proteins, piRNAs and retrotransposons. piRNA-associated proteins MVH and Miwi are upregulated in leptotene to pachytene spermatocytes with a more precocious timing in AhR−/− than in AhR+/+ testes. piRNAs and transcripts from B1-SINE, LINE-1 and IAP retrotransposons increased at these meiotic stages in AhR-null testes. Moreover, B1-SINE transcripts colocalize with MVH and Miwi in leptonema and pachynema spermatocytes. Unexpectedly, AhR−/− males have increased sperm counts, higher sperm functionality and enhanced fertility than AhR+/+ mice. In contrast, piRNA-associated proteins and B1-SINE and IAP-derived transcripts are reduced in adult AhR−/− ovaries. Accordingly, AhR-null female mice have lower numbers of follicles when compared with AhR+/+ mice. Thus, AhR deficiency differentially affects testis and ovary development possibly by a process involving piRNA-associated proteins, piRNAs and transposable elements.
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Affiliation(s)
- Eva M Rico-Leo
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias, Universidad de Extremadura, Badajoz, Spain
| | - Nuria Moreno-Marín
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias, Universidad de Extremadura, Badajoz, Spain
| | - Francisco J González-Rico
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias, Universidad de Extremadura, Badajoz, Spain
| | - Eva Barrasa
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias, Universidad de Extremadura, Badajoz, Spain
| | - Cristina Ortega-Ferrusola
- Laboratorio de Reproducción y Espermatología Equina, Hospital Veterinario, Universidad de Extremadura, Cáceres, Spain
| | - Patricia Martín-Muñoz
- Laboratorio de Reproducción y Espermatología Equina, Hospital Veterinario, Universidad de Extremadura, Cáceres, Spain
| | - Luis O Sánchez-Guardado
- Departamento de Anatomía, Biología Celular y Zoología, Facultad de Ciencias, Universidad de Extremadura, Badajoz, Spain
| | - Elena Llano
- Departamento de Fisiología, Universidad de Salamanca, Salamanca, Spain.,Instituto de Biología Molecular y Celular del Cáncer (CSIC-Universidad de Salamanca), Salamanca, Spain
| | | | | | | | - Matías Hidalgo-Sánchez
- Departamento de Anatomía, Biología Celular y Zoología, Facultad de Ciencias, Universidad de Extremadura, Badajoz, Spain
| | - Dirk G de Rooij
- Reproductive Biology Group, Division of Developmental Biology, Department of Biology, Faculty of Science, Utrecht University, Utrecht, The Netherlands
| | - Alberto M Pendás
- Instituto de Biología Molecular y Celular del Cáncer (CSIC-Universidad de Salamanca), Salamanca, Spain
| | - Fernando J Peña
- Laboratorio de Reproducción y Espermatología Equina, Hospital Veterinario, Universidad de Extremadura, Cáceres, Spain
| | - Jaime M Merino
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias, Universidad de Extremadura, Badajoz, Spain
| | - Pedro M Fernández-Salguero
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias, Universidad de Extremadura, Badajoz, Spain
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9
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Abstract
Endogenous electric fields (EFs) are involved in developmental regulation and wound healing. Although the phenomenon is known for more than a century, it is not clear how cells perceive the external EF. Membrane proteins, responding to electrophoretic and electroosmotic forces, have long been proposed as the sensing molecules. However, specific charge modification of surface proteins did not change cell migration motility nor directionality in EFs. Moreover, symmetric alternating current (AC) EF directs cell migration in a frequency-dependent manner. Due to their charge and ability to coalesce, glycolipids are therefore the likely primary EF sensor driving polarization of membrane proteins and intracellular signaling. We demonstrate that detergent-resistant membrane nanodomains, also known as lipid rafts, are the primary response element in EF sensing. The clustering and activation of caveolin and signaling proteins further stabilize raft structure and feed-forward downstream signaling events, such as rho and PI3K activation. Theoretical modeling supports the experimental results and predicts AC frequency-dependent cell and raft migration. Our results establish a fundamental mechanism for cell electrosensing and provide a role in lipid raft mechanotransduction.
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10
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Lin LF, Wu MH, Pidugu VK, Ho IC, Su TL, Lee TC. P-glycoprotein attenuates DNA repair activity in multidrug-resistant cells by acting through the Cbp-Csk-Src cascade. Oncotarget 2017; 8:45072-45087. [PMID: 28178691 PMCID: PMC5542168 DOI: 10.18632/oncotarget.15065] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2016] [Accepted: 01/24/2017] [Indexed: 11/25/2022] Open
Abstract
Recent studies have demonstrated that P-glycoprotein (P-gp) expression impairs DNA interstrand cross-linking agent-induced DNA repair efficiency in multidrug-resistant (MDR) cells. To date, the detailed molecular mechanisms underlying how P-gp interferes with Src activation and subsequent DNA repair activity remain unclear. In this study, we determined that the C-terminal Src kinase-binding protein (Cbp) signaling pathway involved in the negative control of Src activation is enhanced in MDR cells. We also demonstrated that cells that ectopically express P-gp exhibit reduced activation of DNA damage response regulators, such as ATM, Chk2, Braca1 and Nbs1 and hence attenuated DNA double-strand break repair capacity and become more susceptible than vector control cells to DNA interstrand cross-linking (ICL) agents. Moreover, we demonstrated that P-gp can not only interact with Cbp and Src but also enhance the formation of inhibitory C-terminal Src kinase (Csk)-Cbp complexes that reduce phosphorylation of the Src activation residue Y416 and increase phosphorylation of the Src negative regulatory residue Y527. Notably, suppression of Cbp expression in MDR cells restores cisplatin-induced Src activation, improves DNA repair capacity, and increases resistance to ICL agents. Ectopic expression of Cbp attenuates cisplatin-induced Src activation and increases the susceptibility of cells to ICL agents. Together, the current results indicate that P-gp inhibits DNA repair activity by modulating Src activation via Cbp-Csk-Src cascade. These results suggest that DNA ICL agents are likely to have therapeutic potential against MDR cells with P-gp-overexpression.
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Affiliation(s)
- Li-Fang Lin
- Institute of Biomedical Sciences, Academia Sinica, Taipei 11529, Taiwan
| | - Ming-Hsi Wu
- Institute of Biomedical Sciences, Academia Sinica, Taipei 11529, Taiwan
| | - Vijaya Kumar Pidugu
- Institute of Biomedical Sciences, Academia Sinica, Taipei 11529, Taiwan.,Taiwan International Graduate Program in Molecular Medicine, National Yang-Ming University, Academia Sinica, Taipei 11529, Taiwan
| | - I-Ching Ho
- Institute of Biomedical Sciences, Academia Sinica, Taipei 11529, Taiwan
| | - Tsann-Long Su
- Institute of Biomedical Sciences, Academia Sinica, Taipei 11529, Taiwan
| | - Te-Chang Lee
- Institute of Biomedical Sciences, Academia Sinica, Taipei 11529, Taiwan.,Taiwan International Graduate Program in Molecular Medicine, National Yang-Ming University, Academia Sinica, Taipei 11529, Taiwan.,Institute of Pharmacology, National Yang-Ming University, Taipei 11221, Taiwan
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11
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Environmental Ligands of the Aryl Hydrocarbon Receptor and Their Effects in Models of Adult Liver Progenitor Cells. Stem Cells Int 2016; 2016:4326194. [PMID: 27274734 PMCID: PMC4870370 DOI: 10.1155/2016/4326194] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2016] [Accepted: 04/07/2016] [Indexed: 12/20/2022] Open
Abstract
The toxicity of environmental and dietary ligands of the aryl hydrocarbon receptor (AhR) in mature liver parenchymal cells is well appreciated, while considerably less attention has been paid to their impact on cell populations exhibiting phenotypic features of liver progenitor cells. Here, we discuss the results suggesting that the consequences of the AhR activation in the cellular models derived from bipotent liver progenitors could markedly differ from those in hepatocytes. In contact-inhibited liver progenitor cells, the AhR agonists induce a range of effects potentially linked with tumor promotion. They can stimulate cell cycle progression/proliferation and deregulate cell-to-cell communication, which is associated with downregulation of proteins forming gap junctions, adherens junctions, and desmosomes (such as connexin 43, E-cadherin, β-catenin, and plakoglobin), as well as with reduced cell adhesion and inhibition of intercellular communication. At the same time, toxic AhR ligands may affect the activity of the signaling pathways contributing to regulation of liver progenitor cell activation and/or differentiation, such as downregulation of Wnt/β-catenin and TGF-β signaling, or upregulation of transcriptional targets of YAP/TAZ, the effectors of Hippo signaling pathway. These data illustrate the need to better understand the potential role of liver progenitors in the AhR-mediated liver carcinogenesis and tumor promotion.
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Park JH, Choi AJ, Kim SJ, Jeong SY. 3,3'-Diindolylmethane Inhibits Flt3L/GM-CSF-induced-bone Marrow-derived CD103(+) Dendritic Cell Differentiation Regulating Phosphorylation of STAT3 and STAT5. Immune Netw 2015; 15:278-90. [PMID: 26770182 PMCID: PMC4700404 DOI: 10.4110/in.2015.15.6.278] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2015] [Revised: 11/05/2015] [Accepted: 11/07/2015] [Indexed: 01/05/2023] Open
Abstract
The intestinal immune system maintains oral tolerance to harmless antigens or nutrients. One mechanism of oral tolerance is mediated by regulatory T cell (Treg)s, of which differentiation is regulated by a subset of dendritic cell (DC)s, primarily CD103+ DCs. The aryl hydrocarbon receptor (AhR), a ligand-activated transcription factor, plays an important role in regulating immunity. The intestines are exposed to various AhR ligands, including endogenous metabolites and phytochemicals. It was previously reported that AhR activation induced tolerogenic DCs in mice or in cultures of bone marrow-derived DCs. However, given the variety of tolerogenic DCs, which type of tolerogenic DCs is regulated by AhR remains unknown. In this study, we found that AhR ligand 3,3'-diindolylmethane (DIM) inhibited the development of CD103+ DCs from mouse bone marrow cells stimulated with Flt3L and GM-CSF. DIM interfered with phosphorylation of STAT3 and STAT5 inhibiting the expression of genes, including Id2, E2-2, IDO-1, and Aldh1a2, which are associated with DC differentiation and functions. Finally, DIM suppressed the ability of CD103+ DCs to induce Foxp3+ Tregs.
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Affiliation(s)
- Joo-Hung Park
- Department of Biology, Changwon National University, Changwon 51140, Korea
| | - Ah-Jeong Choi
- Department of Biology, Changwon National University, Changwon 51140, Korea
| | - Soo-Ji Kim
- Department of Biology, Changwon National University, Changwon 51140, Korea
| | - So-Yeon Jeong
- Department of Biology, Changwon National University, Changwon 51140, Korea
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Contador-Troca M, Alvarez-Barrientos A, Merino JM, Morales-Hernández A, Rodríguez MI, Rey-Barroso J, Barrasa E, Cerezo-Guisado MI, Catalina-Fernández I, Sáenz-Santamaría J, Oliver FJ, Fernandez-Salguero PM. Dioxin receptor regulates aldehyde dehydrogenase to block melanoma tumorigenesis and metastasis. Mol Cancer 2015; 14:148. [PMID: 26242870 PMCID: PMC4524442 DOI: 10.1186/s12943-015-0419-9] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2015] [Accepted: 07/22/2015] [Indexed: 01/16/2023] Open
Abstract
Background The dioxin (AhR) receptor can have oncogenic or tumor suppressor activities depending on the phenotype of the target cell. We have shown that AhR knockdown promotes melanoma primary tumorigenesis and lung metastasis in the mouse and that human metastatic melanomas had reduced AhR levels with respect to benign nevi. Methods Mouse melanoma B16F10 cells were engineered by retroviral transduction to stably downregulate AhR expression, Aldh1a1 expression or both. They were characterized for Aldh1a1 activity, stem cell markers and migration and invasion in vitro. Their tumorigenicity in vivo was analyzed using xenografts and lung metastasis assays as well as in vivo imaging. Results Depletion of aldehyde dehydrogenase 1a1 (Aldh1a1) impairs the pro-tumorigenic and pro-metastatic advantage of melanoma cells lacking AhR expression (sh-AhR). Thus, Aldh1a1 knockdown in sh-AhR cells (sh-AhR + sh-Aldh1a1) diminished their migration and invasion potentials and blocked tumor growth and metastasis to the lungs in immunocompetent AhR+/+ recipient mice. However, Aldh1a1 downmodulation in AhR-expressing B16F10 cells did not significantly affect tumor growth in vivo. Aldh1a1 knockdown reduced the high levels of CD133+/CD29+/CD44+ cells, melanosphere size and the expression of the pluripotency marker Sox2 in sh-AhR cells. Interestingly, Sox2 increased Aldh1a1 expression in sh-AhR but not in sh-AhR + sh-Aldh1a1 cells, suggesting that Aldh1a1 and Sox2 may be co-regulated in melanoma cells. In vivo imaging revealed that mice inoculated with AhR + Aldh1a1 knockdown cells had reduced tumor burden and enhanced survival than those receiving Aldh1a1-expressing sh-AhR cells. Conclusions Aldh1a1 overactivation in an AhR-deficient background enhances melanoma progression. Since AhR may antagonize the protumoral effects of Aldh1a1, the AhRlow-Aldh1a1high phenotype could be indicative of bad outcome in melanoma. Electronic supplementary material The online version of this article (doi:10.1186/s12943-015-0419-9) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- María Contador-Troca
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias, 06071, Badajoz, Spain.
| | | | - Jaime M Merino
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias, 06071, Badajoz, Spain.
| | | | - María I Rodríguez
- Instituto de Parasitología y Biomedicina López Neyra, CSIC, 18016, Granada, Spain.
| | - Javier Rey-Barroso
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias, 06071, Badajoz, Spain.
| | - Eva Barrasa
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias, 06071, Badajoz, Spain.
| | - María I Cerezo-Guisado
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias, 06071, Badajoz, Spain.
| | | | - Javier Sáenz-Santamaría
- Servicio de Anatomía Patológica, Hospital Universitario Infanta Cristina, 06071, Badajoz, Spain.
| | - Francisco J Oliver
- Instituto de Parasitología y Biomedicina López Neyra, CSIC, 18016, Granada, Spain.
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Stockinger B, Di Meglio P, Gialitakis M, Duarte JH. The aryl hydrocarbon receptor: multitasking in the immune system. Annu Rev Immunol 2014; 32:403-32. [PMID: 24655296 DOI: 10.1146/annurev-immunol-032713-120245] [Citation(s) in RCA: 648] [Impact Index Per Article: 64.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The aryl hydrocarbon receptor (AhR), for many years almost exclusively studied by the pharmacology/toxicology field for its role in mediating the toxicity of xenobiotics such as 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), has more recently attracted the attention of immunologists. The evolutionary conservation of this transcription factor and its widespread expression in the immune system point to important physiological functions that are slowly being unraveled. In particular, the emphasis is now shifting from the role of AhR in the xenobiotic pathway toward its mode of action in response to physiological ligands. In this article, we review the current understanding of the molecular interactions and functions of AhR in the immune system in steady state and in the presence of infection and inflammation, with a focus on barrier organs such as the skin, the gut, and the lung.
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Affiliation(s)
- Brigitta Stockinger
- Division of Molecular Immunology, MRC National Institute for Medical Research, Mill Hill, London NW7 1AA, United Kingdom; , , ,
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Rey-Barroso J, Alvarez-Barrientos A, Rico-Leo E, Contador-Troca M, Carvajal-Gonzalez JM, Echarri A, Del Pozo MA, Fernandez-Salguero PM. The Dioxin receptor modulates Caveolin-1 mobilization during directional migration: role of cholesterol. Cell Commun Signal 2014; 12:57. [PMID: 25238970 PMCID: PMC4172968 DOI: 10.1186/s12964-014-0057-7] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2014] [Accepted: 09/05/2014] [Indexed: 01/16/2023] Open
Abstract
Background Adhesion and migration are relevant physiological functions that must be regulated by the cell under both normal and pathological conditions. The dioxin receptor (AhR) has emerged as a transcription factor regulating both processes in mesenchymal, epithelial and endothelial cells. Indirect results suggest that AhR could cooperate not only with additional transcription factors but also with membrane-associated proteins to drive such processes. Results In this study, we have used immortalized and primary dermal fibroblasts from wild type (AhR+/+) and AhR-null (AhR−/−) mice to show that AhR modulates membrane distribution and mobilization of caveolin-1 (Cav-1) during directional cell migration. AhR co-immunoprecipitated with Cav-1 and a fraction of both proteins co-localized to detergent-resistant membrane microdomains (DRM). Consistent with a role of AhR in the process, AhR−/− cells had a significant reduction in Cav-1 in DRMs. Moreover, high cell density reduced AhR nuclear levels and moved Cav-1 from DRMs to the soluble membrane in AhR+/+ but not in AhR−/− cells. Tyrosine-14 phosphorylation had a complex role in the mechanism since its upregulation reduced Cav-1 in DRMs in both AhR+/+ and AhR−/−cells, despite the lower basal levels of Y14-Cav-1 in the null cells. Fluorescence recovery after photobleaching revealed that AhR knock-down blocked Cav-1 transport to the plasma membrane, a deficit possibly influencing its depleted levels in DRMs. Membrane distribution of Cav-1 in AhR-null fibroblasts correlated with higher levels of cholesterol and with disrupted membrane microdomains, whereas addition of exogenous cholesterol changed the Cav-1 distribution of AhR+/+ cells to the null phenotype. Consistently, higher cholesterol levels enhanced caveolae-dependent endocytosis in AhR-null cells. Conclusions These results suggest that AhR modulates Cav-1 distribution in migrating cells through the control of cholesterol-enriched membrane microdomains. Our study also supports the likely possibility of membrane-related, transcription factor independent, functions of AhR. Electronic supplementary material The online version of this article (doi:10.1186/s12964-014-0057-7) contains supplementary material, which is available to authorized users.
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Hwang YJ, Yun MO, Jeong KT, Park JH. Uremic toxin indoxyl 3-sulfate regulates the differentiation of Th2 but not of Th1 cells to lessen allergic asthma. Toxicol Lett 2013; 225:130-8. [PMID: 24291743 DOI: 10.1016/j.toxlet.2013.11.027] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2013] [Revised: 11/19/2013] [Accepted: 11/21/2013] [Indexed: 01/01/2023]
Abstract
Immune system dysfunctions including the increased Th1/Th2 ratio are common in chronic kidney disease (CKD) patients, and a wide variety of skin diseases including Th1-mediated uremic pruritis are associated with CKD. Although there are more than 90 uremic toxins reported, it is yet to be known which uremic solute is associated with the unbalanced Th1/Th2 ratio and how it works. Indoxyl 3-sulfate (I3S), one of uremic toxins and a potent aryl hydrocarbon receptor (AhR) ligand, accumulates in blood and tissues, increasing up to 81.04 μM in CKD patients, compared with 1.03 μM in healthy subjects. I3S activates NF-κB and AhR. Thus, we investigated roles of I3S in the differentiation of Th1 and Th2 cells. I3S inhibited Th2 differentiation but showed little or no effect on Th1 differentiation. I3S suppressed Th2-mediated ovalbumin-induced allergic asthma in mice and decreased the frequency of IL-4 producing CD4 T cells in the lungs. I3S inhibited phosphorylation of STAT5 and STAT6, transcription factors associated with Th2 differentiation. Effects of I3S on Th2 differentiation were suppressed by α-naphtoflavone, an AhR antagonist, indicating that I3S regulates Th2 differentiation AhR-dependently.
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Affiliation(s)
- You-Jung Hwang
- Department of Biology, Changwon National University, Kyungnam, Changwon, 641-773, South Korea
| | - Mi-Ok Yun
- Department of Biology, Changwon National University, Kyungnam, Changwon, 641-773, South Korea
| | - Kyu-Tae Jeong
- Department of Biology, Changwon National University, Kyungnam, Changwon, 641-773, South Korea
| | - Joo-Hung Park
- Department of Biology, Changwon National University, Kyungnam, Changwon, 641-773, South Korea.
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Hrdinka M, Horejsi V. PAG - a multipurpose transmembrane adaptor protein. Oncogene 2013; 33:4881-92. [DOI: 10.1038/onc.2013.485] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2013] [Revised: 09/25/2013] [Accepted: 09/25/2013] [Indexed: 12/25/2022]
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Contador-Troca M, Alvarez-Barrientos A, Barrasa E, Rico-Leo EM, Catalina-Fernández I, Menacho-Márquez M, Bustelo XR, García-Borrón JC, Gómez-Durán A, Sáenz-Santamaría J, Fernández-Salguero PM. The dioxin receptor has tumor suppressor activity in melanoma growth and metastasis. Carcinogenesis 2013; 34:2683-93. [PMID: 23843039 DOI: 10.1093/carcin/bgt248] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Melanoma is a highly metastatic and malignant skin cancer having poor rates of patient survival. Since the incidence of melanoma is steadily increasing in the population, finding prognostic and therapeutic targets are crucial tasks in cancer. The dioxin receptor (AhR) is required for xenobiotic-induced toxicity and carcinogenesis and for cell physiology and organ homeostasis. Yet, the mechanisms by which AhR affects tumor growth and dissemination are largely uncharacterized. We report here that AhR contributes to the tumor-stroma interaction, blocking melanoma growth and metastasis when expressed in the tumor cell but supporting melanoma when expressed in the stroma. B16F10 cells engineered to lack AhR (small hairpin RNA for AhR) exacerbated melanoma primary tumorigenesis and lung metastasis when injected in AhR+/+ recipient mice but not when injected in AhR- /- mice or when co-injected with AhR-/- fibroblasts in an AhR+/+ stroma. Contrary, B16F10 cells expressing a constitutively active AhR had reduced tumorigenicity and invasiveness in either AhR genetic background. The tumor suppressor role of AhR in melanoma cells correlated with reduced migration and invasion, with lower numbers of cancer stem-like cells and with altered levels of β1-integrin and caveolin1. Human melanoma cell lines with highest AHR expression also had lowest migration and invasion. Moreover, AHR expression was reduced in human melanomas with respect to nevi lesions. We conclude that AhR knockdown in melanoma cells requires stromal AhR for maximal tumor progression and metastasis. Thus, AhR can be a molecular marker in melanoma and its activity in both tumor and stromal compartments should be considered.
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Indoxyl 3-sulfate stimulates Th17 differentiation enhancing phosphorylation of c-Src and STAT3 to worsen experimental autoimmune encephalomyelitis. Toxicol Lett 2013; 220:109-17. [PMID: 23639249 DOI: 10.1016/j.toxlet.2013.04.016] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2013] [Revised: 04/19/2013] [Accepted: 04/21/2013] [Indexed: 01/01/2023]
Abstract
Although AhR activation regulates CD4T cell differentiation, how it works has yet to be elucidated. In the present study, using in vitro Th17 differentiation model, we examined effects of AhR activation by indoxyl 3-sulfate (I3S), a uremic toxin, on Th17 differentiation and investigated underlying mechanisms. I3S increased expression of RORγt, the master transcription factor for Th17 differentiation, and stimulated Th17 differentiation, in a comparative manner as 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), a prototypical AhR ligand. Activation of STAT3, which is phosphorylated by the IL-6 signaling pathways and thus is necessary for Th17 differentiation, was strongly stimulated by I3S and TCDD. Phosphorylation of c-Src, which was shown to be activated by AhR ligands, was also increased by I3S and TCDD, and blocking of c-Src activity by 4-amino-5-(4-chlorophenyl)-7-(t-butyl) pyrazolo[3,4-d]pyrimidine (PP2) inhibited phosphorylation of both c-Src and STAT3, raising a possibility that stimulatory activities of I3S and TCDD on Th17 differentiation could be exerted via increased phosphorylation of c-Src, which in turn stimulates STAT3 activation. Finally, we found that I3S worsened experimental autoimmune encephalomyelitis (EAE), which is primarily mediated by Th17 cells, enhancing the frequency of IL-17-producing cells in draining lymph nodes.
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