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Fan W, Cao D, Yang B, Wang J, Li X, Kitka D, Li TWH, You S, Shiao S, Gangi A, Posadas E, Di Vizio D, Tomasi ML, Seki E, Mato JM, Yang H, Lu SC. Hepatic prohibitin 1 and methionine adenosyltransferase α1 defend against primary and secondary liver cancer metastasis. J Hepatol 2024; 80:443-453. [PMID: 38086446 PMCID: PMC10922446 DOI: 10.1016/j.jhep.2023.11.022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/30/2023] [Revised: 11/06/2023] [Accepted: 11/13/2023] [Indexed: 12/24/2023]
Abstract
BACKGROUND & AIMS The liver is a common site of cancer metastasis, most commonly from colorectal cancer, and primary liver cancers that have metastasized are associated with poor outcomes. The underlying mechanisms by which the liver defends against these processes are largely unknown. Prohibitin 1 (PHB1) and methionine adenosyltransferase 1A (MAT1A) are highly expressed in the liver. They positively regulate each other and their deletion results in primary liver cancer. Here we investigated their roles in primary and secondary liver cancer metastasis. METHODS We identified common target genes of PHB1 and MAT1A using a metastasis array, and measured promoter activity and transcription factor binding using luciferase reporter assays and chromatin immunoprecipitation, respectively. We examined how PHB1 or MAT1A loss promotes liver cancer metastasis and whether their loss sensitizes to colorectal liver metastasis (CRLM). RESULTS Matrix metalloproteinase-7 (MMP-7) is a common target of MAT1A and PHB1 and its induction is responsible for increased migration and invasion when MAT1A or PHB1 is silenced. Mechanistically, PHB1 and MAT1A negatively regulate MMP7 promoter activity via an AP-1 site by repressing the MAFG-FOSB complex. Loss of MAT1A or PHB1 also increased MMP-7 in extracellular vesicles, which were internalized by colon and pancreatic cancer cells to enhance their oncogenicity. Low hepatic MAT1A or PHB1 expression sensitized to CRLM, but not if endogenous hepatic MMP-7 was knocked down first, which lowered CD4+ T cells while increasing CD8+ T cells in the tumor microenvironment. Hepatocytes co-cultured with colorectal cancer cells express less MAT1A/PHB1 but more MMP-7. Consistently, CRLM raised distant hepatocytes' MMP-7 expression in mice and humans. CONCLUSION We have identified a PHB1/MAT1A-MAFG/FOSB-MMP-7 axis that controls primary liver cancer metastasis and sensitization to CRLM. IMPACT AND IMPLICATIONS Primary and secondary liver cancer metastasis is associated with poor outcomes but whether the liver has underlying defense mechanism(s) against metastasis is unknown. Here we examined the hypothesis that hepatic prohibitin 1 (PHB1) and methionine adenosyltransferase 1A (MAT1A) cooperate to defend the liver against metastasis. Our studies found PHB1 and MAT1A form a complex that suppresses matrix metalloproteinase-7 (MMP-7) at the transcriptional level and loss of either PHB1 or MAT1A sensitizes the liver to metastasis via MMP-7 induction. Strategies that target the PHB1/MAT1A-MMP-7 axis may be a promising approach for the treatment of primary and secondary liver cancer metastasis.
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Affiliation(s)
- Wei Fan
- Karsh Division of Gastroenterology and Hepatology, Cedars-Sinai Medical Center (CSMC), Los Angeles, CA 90048, USA
| | - DuoYao Cao
- Department of Biomedical Sciences, CSMC, Los Angeles, CA 90048, USA
| | - Bing Yang
- Karsh Division of Gastroenterology and Hepatology, Cedars-Sinai Medical Center (CSMC), Los Angeles, CA 90048, USA; Department of Geriatric Endocrinology and Metabolism, Guangxi Key Laboratory of Precision Medicine in Cardio-cerebrovascular Diseases Control and Prevention, Guangxi Clinical Research Center for Cardio-cerebrovascular Diseases, The First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi, 530021, China
| | - Jiaohong Wang
- Karsh Division of Gastroenterology and Hepatology, Cedars-Sinai Medical Center (CSMC), Los Angeles, CA 90048, USA
| | - Xiaomo Li
- Department of Pathology, CSMC, Los Angeles CA 90048, USA
| | - Diana Kitka
- Department of Biomedical Sciences, CSMC, Los Angeles, CA 90048, USA; Department of Surgery, Cedars-Sinai Cancer, CSMC, Los Angeles, CA, 90048, USA
| | - Tony W H Li
- Karsh Division of Gastroenterology and Hepatology, Cedars-Sinai Medical Center (CSMC), Los Angeles, CA 90048, USA
| | - Sungyong You
- Department of Biomedical Sciences, CSMC, Los Angeles, CA 90048, USA; Department of Surgery, Cedars-Sinai Cancer, CSMC, Los Angeles, CA, 90048, USA
| | - Stephen Shiao
- Department of Radiation Oncology, CSMC, LA, CA 90048, USA
| | | | | | - Dolores Di Vizio
- Department of Biomedical Sciences, CSMC, Los Angeles, CA 90048, USA; Department of Surgery, Cedars-Sinai Cancer, CSMC, Los Angeles, CA, 90048, USA
| | - Maria Lauda Tomasi
- Karsh Division of Gastroenterology and Hepatology, Cedars-Sinai Medical Center (CSMC), Los Angeles, CA 90048, USA
| | - Ekihiro Seki
- Karsh Division of Gastroenterology and Hepatology, Cedars-Sinai Medical Center (CSMC), Los Angeles, CA 90048, USA
| | - José M Mato
- CIC bioGUNE, Centro de Investigación Biomédica en Red de Enfermedades Hepáticasy Digestivas (Ciberehd), Basque Research and Technology Alliance (BRTA), Technology, Park of Bizkaia, 48160 Derio, Bizkaia, Spain
| | - Heping Yang
- Karsh Division of Gastroenterology and Hepatology, Cedars-Sinai Medical Center (CSMC), Los Angeles, CA 90048, USA
| | - Shelly C Lu
- Karsh Division of Gastroenterology and Hepatology, Cedars-Sinai Medical Center (CSMC), Los Angeles, CA 90048, USA.
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Wang JP, Leng JY, Zhang RK, Zhang L, Zhang B, Jiang WY, Tong L. Functional analysis of gene expression profiling-based prediction in bladder cancer. Oncol Lett 2018; 15:8417-8423. [PMID: 29805577 PMCID: PMC5950606 DOI: 10.3892/ol.2018.8370] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2016] [Accepted: 11/02/2017] [Indexed: 02/07/2023] Open
Abstract
The present study aimed to analyze the modification of gene expression in bladder cancer (BC) by identifying significant differentially expressed genes (DEGs) and functionally assess them using bioinformatics analysis. To achieve this, two microarray datasets, GSE24152 (which included 10 fresh tumor tissue samples from urothelial bladder carcinoma patients and 7 benign mucosa samples from the bladder), and GSE42089 (which included 10 tissues samples from urothelial cell carcinoma patients and 8 tissues samples from the normal bladder), were downloaded from the Gene Expression Omnibus database for further analysis. Differentially expressed genes (DEGs) were screened between benign the mucosa and control groups in GSE24152 and GSE42089 datasets. Gene ontology (GO) and Kyoto encyclopedia of genes and genomes (KEGG) analysis were performed on overlapping DEGs identified in GSE24152 and GSE42089. Protein-protein interaction (PPI) networks and sub-networks were then constructed to identify key genes and main pathways. GO terms analysis was also performed for the selected clusters. In total, 1,325 DEGs in GSE24152 and 647 DEGs in GSE42089 were screened, in which 619 common DEGs were identified. The DEGs were mainly enriched in pathways and GO terms associated with mitotic and chromosome assembly, including nucleosome assembly, spindle checkpoint and DNA replication. In the interaction network, progesterone receptor (PGR), MAF bZIP transcription factor G (MAFG), cell division cycle 6 (CDC6) and members of the minichromosome maintenance family (MCMs) were identified as key genes. Histones were also considered to be significant factors in BC. Nucleosome assembly and sequence-specific DNA binding were the most significant clustered GO terms. In conclusion, the DEGs, including PGR, MAFG, CDC6 and MCMs, and those encoding the core histone family were closely associated with the development of BC via pathways associated with mitotic and chromosome assembly.
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Affiliation(s)
- Ji-Ping Wang
- Department of Radiology, The First Hospital of Jilin University, Changchun, Jilin 130021, P.R. China
| | - Ji-Yan Leng
- Department of Geratology, The First Hospital of Jilin University, Changchun, Jilin 130021, P.R. China
| | - Rong-Kui Zhang
- Department of Radiology, The First Hospital of Jilin University, Changchun, Jilin 130021, P.R. China
| | - Li Zhang
- Department of Radiology, The First Hospital of Jilin University, Changchun, Jilin 130021, P.R. China
| | - Bei Zhang
- Department of Radiology, The First Hospital of Jilin University, Changchun, Jilin 130021, P.R. China
| | - Wen-Yan Jiang
- Department of Radiology, The First Hospital of Jilin University, Changchun, Jilin 130021, P.R. China
| | - Lan Tong
- Department of Radiology, The First Hospital of Jilin University, Changchun, Jilin 130021, P.R. China
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Potential Roles of Amiloride-Sensitive Sodium Channels in Cancer Development. BIOMED RESEARCH INTERNATIONAL 2016; 2016:2190216. [PMID: 27403419 PMCID: PMC4926023 DOI: 10.1155/2016/2190216] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/28/2016] [Revised: 04/18/2016] [Accepted: 05/23/2016] [Indexed: 12/15/2022]
Abstract
The ENaC/degenerin ion channel superfamily includes the amiloride-sensitive epithelial sodium channel (ENaC) and acid sensitive ionic channel (ASIC). ENaC is a multimeric ion channel formed by heteromultimeric membrane glycoproteins, which participate in a multitude of biological processes by mediating the transport of sodium (Na+) across epithelial tissues such as the kidney, lungs, bladder, and gut. Aberrant ENaC functions contribute to several human disease states including pseudohypoaldosteronism, Liddle syndrome, cystic fibrosis, and salt-sensitive hypertension. Increasing evidence suggests that ion channels not only regulate ion homeostasis and electric signaling in excitable cells but also play important roles in cancer cell behaviors such as proliferation, apoptosis, invasion, and migration. Indeed, ENaCs/ASICs had been reported to be associated with cancer characteristics. Given their cell surface localization and pharmacology, pharmacological strategies to target ENaC/ASIC family members may be promising cancer therapeutics.
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Nomoto H, Kondo T, Miyoshi H, Nakamura A, Hida Y, Yamashita KI, Sharma AJ, Atsumi T. Inhibition of Small Maf Function in Pancreatic β-Cells Improves Glucose Tolerance Through the Enhancement of Insulin Gene Transcription and Insulin Secretion. Endocrinology 2015; 156:3570-80. [PMID: 25763640 PMCID: PMC4588816 DOI: 10.1210/en.2014-1906] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The large-Maf transcription factor v-maf musculoaponeurotic fibrosarcoma oncogene homolog A (MafA) has been found to be crucial for insulin transcription and synthesis and for pancreatic β-cell function and maturation. However, insights about the effects of small Maf factors on β-cells are limited. Our goal was to elucidate the function of small-Maf factors on β-cells using an animal model of endogenous small-Maf dysfunction. Transgenic (Tg) mice with β-cell-specific expression of dominant-negative MafK (DN-MafK) experiments, which can suppress the function of all endogenous small-Mafs, were fed a high-fat diet, and their in vivo phenotypes were evaluated. Phenotypic analysis, glucose tolerance tests, morphologic examination of β-cells, and islet experiments were performed. DN-MafK-expressed MIN6 cells were also used for in vitro analysis. The results showed that DN-MafK expression inhibited endogenous small-Maf binding to insulin promoter while increasing MafA binding. DN-MafK Tg mice under high-fat diet conditions showed improved glucose metabolism compared with control mice via incremental insulin secretion, without causing changes in insulin sensitivity or MafA expression. Moreover, up-regulation of insulin and glucokinase gene expression was observed both in vivo and in vitro under DN-MafK expression. We concluded that endogenous small-Maf factors negatively regulates β-cell function by competing for MafA binding, and thus, the inhibition of small-Maf activity can improve β-cell function.
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Affiliation(s)
- Hiroshi Nomoto
- Division of Rheumatology, Endocrinology and Nephrology (H.N., T.K., H.M., A.N., Y.H., T.A.), and Department of Transplant Surgery (K.Y.), Hokkaido University Graduate School of Medicine, Sapporo, Japan 060-8638; Section of Islet Transplantation and Cell Biology (A.J.S.), Joslin Diabetes Center, Boston, Massachusetts 02215; and MedImmune LLC (A.J.S.), Gaithersburg, Maryland 20878
| | - Takuma Kondo
- Division of Rheumatology, Endocrinology and Nephrology (H.N., T.K., H.M., A.N., Y.H., T.A.), and Department of Transplant Surgery (K.Y.), Hokkaido University Graduate School of Medicine, Sapporo, Japan 060-8638; Section of Islet Transplantation and Cell Biology (A.J.S.), Joslin Diabetes Center, Boston, Massachusetts 02215; and MedImmune LLC (A.J.S.), Gaithersburg, Maryland 20878
| | - Hideaki Miyoshi
- Division of Rheumatology, Endocrinology and Nephrology (H.N., T.K., H.M., A.N., Y.H., T.A.), and Department of Transplant Surgery (K.Y.), Hokkaido University Graduate School of Medicine, Sapporo, Japan 060-8638; Section of Islet Transplantation and Cell Biology (A.J.S.), Joslin Diabetes Center, Boston, Massachusetts 02215; and MedImmune LLC (A.J.S.), Gaithersburg, Maryland 20878
| | - Akinobu Nakamura
- Division of Rheumatology, Endocrinology and Nephrology (H.N., T.K., H.M., A.N., Y.H., T.A.), and Department of Transplant Surgery (K.Y.), Hokkaido University Graduate School of Medicine, Sapporo, Japan 060-8638; Section of Islet Transplantation and Cell Biology (A.J.S.), Joslin Diabetes Center, Boston, Massachusetts 02215; and MedImmune LLC (A.J.S.), Gaithersburg, Maryland 20878
| | - Yoko Hida
- Division of Rheumatology, Endocrinology and Nephrology (H.N., T.K., H.M., A.N., Y.H., T.A.), and Department of Transplant Surgery (K.Y.), Hokkaido University Graduate School of Medicine, Sapporo, Japan 060-8638; Section of Islet Transplantation and Cell Biology (A.J.S.), Joslin Diabetes Center, Boston, Massachusetts 02215; and MedImmune LLC (A.J.S.), Gaithersburg, Maryland 20878
| | - Ken-ichiro Yamashita
- Division of Rheumatology, Endocrinology and Nephrology (H.N., T.K., H.M., A.N., Y.H., T.A.), and Department of Transplant Surgery (K.Y.), Hokkaido University Graduate School of Medicine, Sapporo, Japan 060-8638; Section of Islet Transplantation and Cell Biology (A.J.S.), Joslin Diabetes Center, Boston, Massachusetts 02215; and MedImmune LLC (A.J.S.), Gaithersburg, Maryland 20878
| | - Arun J Sharma
- Division of Rheumatology, Endocrinology and Nephrology (H.N., T.K., H.M., A.N., Y.H., T.A.), and Department of Transplant Surgery (K.Y.), Hokkaido University Graduate School of Medicine, Sapporo, Japan 060-8638; Section of Islet Transplantation and Cell Biology (A.J.S.), Joslin Diabetes Center, Boston, Massachusetts 02215; and MedImmune LLC (A.J.S.), Gaithersburg, Maryland 20878
| | - Tatsuya Atsumi
- Division of Rheumatology, Endocrinology and Nephrology (H.N., T.K., H.M., A.N., Y.H., T.A.), and Department of Transplant Surgery (K.Y.), Hokkaido University Graduate School of Medicine, Sapporo, Japan 060-8638; Section of Islet Transplantation and Cell Biology (A.J.S.), Joslin Diabetes Center, Boston, Massachusetts 02215; and MedImmune LLC (A.J.S.), Gaithersburg, Maryland 20878
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Moon EJ, Giaccia A. Dual roles of NRF2 in tumor prevention and progression: possible implications in cancer treatment. Free Radic Biol Med 2015; 79:292-9. [PMID: 25458917 PMCID: PMC4339613 DOI: 10.1016/j.freeradbiomed.2014.11.009] [Citation(s) in RCA: 130] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/24/2014] [Revised: 11/13/2014] [Accepted: 11/13/2014] [Indexed: 12/16/2022]
Abstract
The cap'n'collar (CNC) family serves as cellular sensors of oxidative and electrophilic stresses and shares structural similarities including basic leucine zipper (bZIP) and CNC domains. They form heterodimers with small MAF proteins to regulate antioxidant and phase II enzymes through antioxidant response element (ARE)-mediated transactivation. Among the CNC family members, NRF2 is required for systemic protection against redox-mediated injury and carcinogenesis. On the other hand, NRF2 is activated by oncogenic pathways, metabolism, and hypoxia. Constitutive NRF2 activation is observed in a variety of human cancers and it is highly correlated with tumor progression and aggressiveness. In this review, we will discuss how NRF2 plays dual roles in cancer prevention and progression depending on the cellular context and environment. Therefore, a better understanding of NRF2 will be necessary to exploit this complex network of balancing antioxidant pathways to inhibit tumor progression.
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Affiliation(s)
- Eui Jung Moon
- Division of Radiation Biology & Oncology, Department of Radiation Oncology, Stanford University, Stanford, CA 94305, USA
| | - Amato Giaccia
- Division of Radiation Biology & Oncology, Department of Radiation Oncology, Stanford University, Stanford, CA 94305, USA.
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Sedlakova O, Svastova E, Takacova M, Kopacek J, Pastorek J, Pastorekova S. Carbonic anhydrase IX, a hypoxia-induced catalytic component of the pH regulating machinery in tumors. Front Physiol 2014; 4:400. [PMID: 24409151 PMCID: PMC3884196 DOI: 10.3389/fphys.2013.00400] [Citation(s) in RCA: 128] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2013] [Accepted: 12/19/2013] [Indexed: 12/19/2022] Open
Abstract
Acidic tissue microenvironment contributes to tumor progression via multiple effects including the activation of angiogenic factors and proteases, reduced cell-cell adhesion, increased migration and invasion, etc. In addition, intratumoral acidosis can influence the uptake of anticancer drugs and modulate the response of tumors to conventional therapy. Acidification of the tumor microenvironment often develops due to hypoxia-triggered oncogenic metabolism, which leads to the extensive production of lactate, protons, and carbon dioxide. In order to avoid intracellular accumulation of the acidic metabolic products, which is incompatible with the survival and proliferation, tumor cells activate molecular machinery that regulates pH by driving transmembrane inside-out and outside-in ion fluxes. Carbonic anhydrase IX (CA IX) is a hypoxia-induced catalytic component of the bicarbonate import arm of this machinery. Through its catalytic activity, CA IX directly participates in many acidosis-induced features of tumor phenotype as demonstrated by manipulating its expression and/or by in vitro mutagenesis. CA IX can function as a survival factor protecting tumor cells from hypoxia and acidosis, as a pro-migratory factor facilitating cell movement and invasion, as a signaling molecule transducing extracellular signals to intracellular pathways (including major signaling and metabolic cascades) and converting intracellular signals to extracellular effects on adhesion, proteolysis, and other processes. These functional implications of CA IX in cancer are supported by numerous clinical studies demonstrating the association of CA IX with various clinical correlates and markers of aggressive tumor behavior. Although our understanding of the many faces of CA IX is still incomplete, existing knowledge supports the view that CA IX is a biologically and clinically relevant molecule, exploitable in anticancer strategies aimed at targeting adaptive responses to hypoxia and/or acidosis.
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Affiliation(s)
- Olga Sedlakova
- Department of Molecular Medicine, Institute of Virology, Slovak Academy of Sciences Bratislava, Slovakia
| | - Eliska Svastova
- Department of Molecular Medicine, Institute of Virology, Slovak Academy of Sciences Bratislava, Slovakia
| | - Martina Takacova
- Department of Molecular Medicine, Institute of Virology, Slovak Academy of Sciences Bratislava, Slovakia
| | - Juraj Kopacek
- Department of Molecular Medicine, Institute of Virology, Slovak Academy of Sciences Bratislava, Slovakia
| | - Jaromir Pastorek
- Department of Molecular Medicine, Institute of Virology, Slovak Academy of Sciences Bratislava, Slovakia
| | - Silvia Pastorekova
- Department of Molecular Medicine, Institute of Virology, Slovak Academy of Sciences Bratislava, Slovakia
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The small MAF transcription factors MAFF, MAFG and MAFK: current knowledge and perspectives. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2012; 1823:1841-6. [PMID: 22721719 DOI: 10.1016/j.bbamcr.2012.06.012] [Citation(s) in RCA: 100] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/27/2012] [Revised: 06/11/2012] [Accepted: 06/12/2012] [Indexed: 12/13/2022]
Abstract
The small MAFs, MAFF, MAFG and MAFK have emerged as crucial regulators of mammalian gene expression. Previous studies have linked small MAF function, by virtue of their heterodimerization with the Cap 'n' Collar (CNC) family of transcription factors, to the stress response and detoxification pathways. Recent analyses have revealed a complex regulatory network involving small MAF transcription factors and other cellular proteins. The expression and activity of small MAFs are tightly regulated at multiple levels. With regard to their clinical importance, small MAFs have been linked to various diseases, such as diabetes, neuronal disorders, thrombocytopenia and carcinogenesis. A better understanding of the molecular mechanisms governing the activity of small MAFs will provide novel insights into the control of mammalian transcription and may lead to the development of novel therapeutic strategies to treat common human disorders.
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Itoh K, Mimura J, Yamamoto M. Discovery of the negative regulator of Nrf2, Keap1: a historical overview. Antioxid Redox Signal 2010; 13:1665-78. [PMID: 20446768 DOI: 10.1089/ars.2010.3222] [Citation(s) in RCA: 394] [Impact Index Per Article: 28.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
An antioxidant response element (ARE) or an electrophile responsive element (EpRE) regulate the transcriptional induction of a battery of drug-detoxifying enzymes that are protective against electrophiles. Based on the high similarity of the ARE consensus sequence to an erythroid gene regulatory element NF-E2 binding site, we have found that the transcription factor Nrf2 is indispensable for the ARE-mediated induction of drug-metabolizing enzymes. Recent genome-wide analysis demonstrated that Nrf2 regulates hundreds of genes that are involved in the cytoprotective response against oxidative stress. In-depth analysis of Nrf2 regulatory mechanisms has led us to the discovery of a novel protein, which we have named Keap1. Keap1 suppresses Nrf2 activity by specifically binding to its evolutionarily conserved N-terminal Neh2 regulatory domain. In this review article, we summarize the findings and observations that have lead to the discovery of the Nrf2-Keap1 system. Furthermore, we briefly discuss the function of the Nrf2-Keap1 system under the regulation of the endogenous electrophilic compound 15-deoxy-Δ¹²(,)¹⁴-prostaglandin J₂. We propose that Nrf2-Keap1 plays a significant physiological role in the response to endogenous, environmental, and pharmacological electrophiles.
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Affiliation(s)
- Ken Itoh
- Department of Stress Response Science, Hirosaki University Graduate School of Medicine, Japan.
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Fréchet M, Warrick E, Vioux C, Chevallier O, Spatz A, Benhamou S, Sarasin A, Bernerd F, Magnaldo T. Overexpression of matrix metalloproteinase 1 in dermal fibroblasts from DNA repair-deficient/cancer-prone xeroderma pigmentosum group C patients. Oncogene 2008; 27:5223-32. [DOI: 10.1038/onc.2008.153] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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10
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Blank V. Small Maf proteins in mammalian gene control: mere dimerization partners or dynamic transcriptional regulators? J Mol Biol 2007; 376:913-25. [PMID: 18201722 DOI: 10.1016/j.jmb.2007.11.074] [Citation(s) in RCA: 108] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2007] [Revised: 11/09/2007] [Accepted: 11/26/2007] [Indexed: 12/13/2022]
Abstract
The small Maf basic leucine zipper (bZIP) proteins MafF, MafG and MafK, while modest in size, have emerged as crucial regulators of mammalian gene expression. Intriguingly, small Mafs do not contain an obvious transcriptional activation domain. However, previously perceived as "mere" partner molecules conferring DNA binding specificity to complexes with larger bZIP proteins, such as the CNC family member Nrf2, it has become clear that small Maf proteins are essential and dynamically regulated transcription factors. Current data suggest stringent control of small Maf protein function through transcriptional and post-translational mechanisms. Initial gene targeting experiments revealed considerable functional redundancy among small Maf proteins in vivo. This was not unexpected, due to the high level of homology among the three small Mafs. Nevertheless, further studies showed that these transcription factors have critical roles in various cellular processes, including stress signaling, hematopoiesis, CNS function and oncogenesis. Recent data provide a possible link between small Maf-mediated transcription and the inflammatory response.
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Affiliation(s)
- Volker Blank
- Lady Davis Institute for Medical Research, 3755, Côte Sainte-Catherine, Montreal, Quebec, Canada.
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Ye JH, Gao J, Wu YN, Hu YJ, Zhang CP, Xu TL. Identification of acid-sensing ion channels in adenoid cystic carcinomas. Biochem Biophys Res Commun 2007; 355:986-92. [PMID: 17324378 DOI: 10.1016/j.bbrc.2007.02.061] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2007] [Accepted: 02/13/2007] [Indexed: 11/19/2022]
Abstract
Tissue acidosis is an important feature of tumor. The response of adenoid cystic carcinoma (ACC) cells to acidic solution was studied using whole-cell patch-clamp recording in the current study. An inward, amiloride-sensitive Na(+) current was identified in cultured ACC-2 cells while not in normal human salivary gland epithelial cells. Electrophysiological and pharmacological properties of the currents suggest that heteromeric acid-sensing ion channels (ASICs) containing 2a and 3 may be responsible for the proton-induced currents in the majority of ACC-2 cells. Consistent with it, analyses of RT-PCR and Western blotting demonstrated the presences of ASIC2a and 3 in ACC-2 cells. Furthermore, we observed the enhanced expression of ASIC2a and 3 in the sample of ACC tissues. These results indicate that the functional expression of ASICs is characteristic feature of ACC cells.
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Affiliation(s)
- Jin-Hai Ye
- Department of Oral and Maxillofacial Surgery, School of Stomatology, Affiliated Ninth People's Hospital, Shanghai Jiaotong University, Shanghai Research Institute of Stomatology, Shanghai 200011, China
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12
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Kumaki I, Yang D, Koibuchi N, Takayama K. Neuronal expression of nuclear transcription factor MafG in the rat medulla oblongata after baroreceptor stimulation. Life Sci 2006; 78:1760-6. [PMID: 16263136 DOI: 10.1016/j.lfs.2005.08.030] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2005] [Accepted: 08/11/2005] [Indexed: 10/25/2022]
Abstract
The medulla oblongata is the site of central baroreceptive neurons in mammals. These neurons express specific basic-leucine zipper transcription factors (bZIP) after baroreceptor stimulation. Previously we showed that activation of baroreceptors induced expression of nuclear transcription factors c-Fos and FosB in central baroreceptive neurons. Here we studied the effects of baroreceptor stimulation on induction of MafG, a member of small Maf protein family that functions as dimeric partners for various bZIP transcription factors by forming transcription-regulating complexes, in the rat medulla oblongata. To determine whether gene expression of MafG is induced by stimulation of arterial baroreceptors, we examined the expression of its mRNA by semi-quantitative reverse transcription-PCR method and its gene product by immunohistochemistry. We found that the number of MafG transcripts increased significantly in the medulla oblongata after baroreceptor stimulation. MafG-immunoreactive neurons were distributed in the nucleus tractus solitarii, the dorsal motor nucleus of the vagus nerve, the ambiguous nucleus and the ventrolateral medulla. The numbers of MafG-immunoreactive neurons in these nuclei were significantly greater in test rats than in saline-injected control rats. We also found approximately 20% of MafG-immunoreactive neurons coexpress FosB after baroreceptor stimulation. Our results suggest that MafG cooperates with FosB to play critical roles as an immediate early gene in the signal transduction of cardiovascular regulation mediated by baroreceptive signals in the medulla oblongata.
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Affiliation(s)
- Iku Kumaki
- Department of Laboratory Sciences, Gunma University School of Health Sciences, 3-39-15 Showa-machi, Maebashi-shi 371-8514, Japan
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Duggan SP, Gallagher WM, Fox EJP, Abdel-Latif MM, Reynolds JV, Kelleher D. Low pH induces co-ordinate regulation of gene expression in oesophageal cells. Carcinogenesis 2005; 27:319-27. [PMID: 16113055 DOI: 10.1093/carcin/bgi211] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The development of gastro-oesophageal reflux disease (GORD) is known to be a causative risk factor in the evolution of adenocarcinoma of the oesophagus. The major component of this reflux is gastric acid. However, the impact of low pH on gene expression has not been extensively studied in oesophageal cells. This study utilizes a transcriptomic and bioinformatic approach to assess regulation of gene expression in response to low pH. In more detail, oesophageal adenocarcinoma cell lines were exposed to a range of pH environments. Affymetrix microarrays were used for gene-expression analysis and results were validated using cycle limitation and real-time RT-PCR analysis, as well as northern and western blotting. Comparative promoter transcription factor binding site (TFBS) analysis (MatInspector) of hierarchically clustered gene-expression data was employed to identify the elements which may co-ordinately regulate individual gene clusters. Initial experiments demonstrated maximal induction of EGR1 gene expression at pH 6.5. Subsequent array experimentation revealed significant induction of gene expression from such functional categories as DNA damage response (EGR1-4, ATF3) and cell-cycle control (GADD34, GADD45, p57). Changes in expression of EGR1, EGR3, ATF3, MKP-1, FOSB, CTGF and CYR61 were verified in separate experiments and in a variety of oesophageal cell lines. TFBS analysis of promoters identified transcription factors that may co-ordinately regulate gene-expression clusters, Cluster 1: Oct-1, AP4R; Cluster 2: NF-kB, EGRF; Cluster 3: IKRS, AP-1F. Low pH has the ability to induce genes and pathways which can provide an environment suitable for the progression of malignancy. Further functional analysis of the genes and clusters identified in this low pH study is likely to lead to new insights into the pathogenesis and therapeutics of GORD and oesophageal cancer.
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Affiliation(s)
- Shane P Duggan
- Department of Clinical Medicine, Institute of Molecular Medicine, Trinity Centre for Health Sciences, St James's Hospital, Dublin 8, Ireland.
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