1
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Chu HY, Chen Z, Wang L, Zhang ZK, Tan X, Liu S, Zhang BT, Lu A, Yu Y, Zhang G. Dickkopf-1: A Promising Target for Cancer Immunotherapy. Front Immunol 2021; 12:658097. [PMID: 34093545 PMCID: PMC8174842 DOI: 10.3389/fimmu.2021.658097] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2021] [Accepted: 05/04/2021] [Indexed: 01/15/2023] Open
Abstract
Clinical studies in a range of cancers have detected elevated levels of the Wnt antagonist Dickkopf-1 (DKK1) in the serum or tumors of patients, and this was frequently associated with a poor prognosis. Our analysis of DKK1 gene profile using data from TCGA also proves the high expression of DKK1 in 14 types of cancers. Numerous preclinical studies have demonstrated the cancer-promoting effects of DKK1 in both in vitro cell models and in vivo animal models. Furthermore, DKK1 showed the ability to modulate immune cell activities as well as the immunosuppressive cancer microenvironment. Expression level of DKK1 is positively correlated with infiltrating levels of myeloid-derived suppressor cells (MDSCs) in 20 types of cancers, while negatively associated with CD8+ T cells in 4 of these 20 cancer types. Emerging experimental evidence indicates that DKK1 has been involved in T cell differentiation and induction of cancer evasion of immune surveillance by accumulating MDSCs. Consequently, DKK1 has become a promising target for cancer immunotherapy, and the mechanisms of DKK1 affecting cancers and immune cells have received great attention. This review introduces the rapidly growing body of literature revealing the cancer-promoting and immune regulatory activities of DKK1. In addition, this review also predicts that by understanding the interaction between different domains of DKK1 through computational modeling and functional studies, the underlying functional mechanism of DKK1 could be further elucidated, thus facilitating the development of anti-DKK1 drugs with more promising efficacy in cancer immunotherapy.
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Affiliation(s)
- Hang Yin Chu
- Law Sau Fai Institute for Advancing Translational Medicine in Bone & Joint Diseases, School of Chinese Medicine, Hong Kong Baptist University, Hong Kong, China.,Guangdong-Hong Kong-Macao Greater Bay Area International Research Platform for Aptamer-based Translational Medicine and Drug Discovery, Hong Kong, China
| | - Zihao Chen
- Guangdong-Hong Kong-Macao Greater Bay Area International Research Platform for Aptamer-based Translational Medicine and Drug Discovery, Hong Kong, China.,School of Chinese Medicine, The Chinese University of Hong Kong, Hong Kong, China
| | - Luyao Wang
- Law Sau Fai Institute for Advancing Translational Medicine in Bone & Joint Diseases, School of Chinese Medicine, Hong Kong Baptist University, Hong Kong, China.,Guangdong-Hong Kong-Macao Greater Bay Area International Research Platform for Aptamer-based Translational Medicine and Drug Discovery, Hong Kong, China
| | - Zong-Kang Zhang
- Guangdong-Hong Kong-Macao Greater Bay Area International Research Platform for Aptamer-based Translational Medicine and Drug Discovery, Hong Kong, China.,School of Chinese Medicine, The Chinese University of Hong Kong, Hong Kong, China
| | - Xinhuan Tan
- Department of Microsurgery (II), Wendeng Hospital of Traditional Chinese Orthopedics and Traumatology of Shandong Province, Wendeng, China
| | - Shuangshuang Liu
- Department of Microsurgery (II), Wendeng Hospital of Traditional Chinese Orthopedics and Traumatology of Shandong Province, Wendeng, China
| | - Bao-Ting Zhang
- Guangdong-Hong Kong-Macao Greater Bay Area International Research Platform for Aptamer-based Translational Medicine and Drug Discovery, Hong Kong, China.,School of Chinese Medicine, The Chinese University of Hong Kong, Hong Kong, China
| | - Aiping Lu
- Law Sau Fai Institute for Advancing Translational Medicine in Bone & Joint Diseases, School of Chinese Medicine, Hong Kong Baptist University, Hong Kong, China.,Guangdong-Hong Kong-Macao Greater Bay Area International Research Platform for Aptamer-based Translational Medicine and Drug Discovery, Hong Kong, China
| | - Yuanyuan Yu
- Law Sau Fai Institute for Advancing Translational Medicine in Bone & Joint Diseases, School of Chinese Medicine, Hong Kong Baptist University, Hong Kong, China.,Guangdong-Hong Kong-Macao Greater Bay Area International Research Platform for Aptamer-based Translational Medicine and Drug Discovery, Hong Kong, China
| | - Ge Zhang
- Law Sau Fai Institute for Advancing Translational Medicine in Bone & Joint Diseases, School of Chinese Medicine, Hong Kong Baptist University, Hong Kong, China.,Guangdong-Hong Kong-Macao Greater Bay Area International Research Platform for Aptamer-based Translational Medicine and Drug Discovery, Hong Kong, China
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2
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Martínez-Gil N, Roca-Ayats N, Atalay N, Pineda-Moncusí M, Garcia-Giralt N, Van Hul W, Boudin E, Ovejero D, Mellibovsky L, Nogués X, Díez-Pérez A, Grinberg D, Balcells S. Functional Assessment of Coding and Regulatory Variants From the DKK1 Locus. JBMR Plus 2020; 4:e10423. [PMID: 33354644 PMCID: PMC7745885 DOI: 10.1002/jbm4.10423] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/21/2020] [Accepted: 10/03/2020] [Indexed: 12/17/2022] Open
Abstract
The DKK1 gene encodes an extracellular inhibitor of the Wnt pathway with an important role in bone tissue development, bone homeostasis, and different critical aspects of bone biology. Several BMD genome‐wide association studies (GWASs) have consistently found association with SNPs in the DKK1 genomic region. For these reasons, it is important to assess the functionality of coding and regulatory variants in the gene. Here, we have studied the functionality of putative regulatory variants, previously found associated with BMD in different studies by others and ourselves, and also six missense variants present in the general population. Using a Wnt‐pathway‐specific luciferase reporter assay, we have determined that the variants p.Ala41Thr, p.Tyr74Phe, p.Arg120Leu, and p.Ser157Ile display a reduced DKK1 inhibitory capacity as compared with WT. This result agrees with the high‐bone‐mass (HBM) phenotype of two women from our cohort who carried mutations p.Tyr74Phe or p.Arg120Leu. On the other hand, by means of a circularized chromosome conformation capture‐ (4C‐) sequencing experiment, we have detected that the region containing 24 BMD‐GWA variants, located 350‐kb downstream of DKK1, interacts both with DKK1 and the LNCAROD (LncRNA‐activating regulator of DKK1, AKA LINC0148) in osteoblastic cells. In conclusion, we have shown that some rare coding variants are partial loss‐of‐function mutations that may lead to a HBM phenotype, whereas the common SNPs associated with BMD in GWASs belong to a putative long‐range regulatory region, through a yet unknown mechanism involving LNCAROD. © 2020 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.
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Affiliation(s)
- Núria Martínez-Gil
- Department of Genetics, Microbiology and Statistics, Faculty of Biology Universitat de Barcelona, Centro de Investigación Biomédica en Red en Enfermedades Raras (CIBERER), Institut de Biomedicina de la Universitat de Barcelona (IBUB), Institut de Recerca Sant Joan de Déu (IRSJD) Barcelona Spain
| | - Neus Roca-Ayats
- Department of Genetics, Microbiology and Statistics, Faculty of Biology Universitat de Barcelona, Centro de Investigación Biomédica en Red en Enfermedades Raras (CIBERER), Institut de Biomedicina de la Universitat de Barcelona (IBUB), Institut de Recerca Sant Joan de Déu (IRSJD) Barcelona Spain
| | - Nurgül Atalay
- Department of Genetics, Microbiology and Statistics, Faculty of Biology Universitat de Barcelona, Centro de Investigación Biomédica en Red en Enfermedades Raras (CIBERER), Institut de Biomedicina de la Universitat de Barcelona (IBUB), Institut de Recerca Sant Joan de Déu (IRSJD) Barcelona Spain
| | - Marta Pineda-Moncusí
- Musculoskeletal Research Group, Hospital del Mar Medical Research Institute Centro de Investigación Biomédica en Red en Fragilidad y Envejecimiento Saludable, ISCIII Barcelona Spain
| | - Natàlia Garcia-Giralt
- Musculoskeletal Research Group, Hospital del Mar Medical Research Institute Centro de Investigación Biomédica en Red en Fragilidad y Envejecimiento Saludable, ISCIII Barcelona Spain
| | - Wim Van Hul
- Center of Medical Genetics University of Antwerp & University Hospital Antwerp Antwerp Belgium
| | - Eveline Boudin
- Center of Medical Genetics University of Antwerp & University Hospital Antwerp Antwerp Belgium
| | - Diana Ovejero
- Musculoskeletal Research Group, Hospital del Mar Medical Research Institute Centro de Investigación Biomédica en Red en Fragilidad y Envejecimiento Saludable, ISCIII Barcelona Spain
| | - Leonardo Mellibovsky
- Musculoskeletal Research Group, Hospital del Mar Medical Research Institute Centro de Investigación Biomédica en Red en Fragilidad y Envejecimiento Saludable, ISCIII Barcelona Spain
| | - Xavier Nogués
- Musculoskeletal Research Group, Hospital del Mar Medical Research Institute Centro de Investigación Biomédica en Red en Fragilidad y Envejecimiento Saludable, ISCIII Barcelona Spain
| | - Adolfo Díez-Pérez
- Musculoskeletal Research Group, Hospital del Mar Medical Research Institute Centro de Investigación Biomédica en Red en Fragilidad y Envejecimiento Saludable, ISCIII Barcelona Spain
| | - Daniel Grinberg
- Department of Genetics, Microbiology and Statistics, Faculty of Biology Universitat de Barcelona, Centro de Investigación Biomédica en Red en Enfermedades Raras (CIBERER), Institut de Biomedicina de la Universitat de Barcelona (IBUB), Institut de Recerca Sant Joan de Déu (IRSJD) Barcelona Spain
| | - Susanna Balcells
- Department of Genetics, Microbiology and Statistics, Faculty of Biology Universitat de Barcelona, Centro de Investigación Biomédica en Red en Enfermedades Raras (CIBERER), Institut de Biomedicina de la Universitat de Barcelona (IBUB), Institut de Recerca Sant Joan de Déu (IRSJD) Barcelona Spain
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3
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Abstract
Wnt signalling regulates cardiogenesis during specification of heart tissue and the morphogenetic movements necessary to form the linear heart. Wnt11-mediated non-canonical signalling promotes early cardiac development whilst Wnt11-R, which is expressed later, also signals through the non-canonical pathway to promote heart development. It is unclear which Frizzled proteins mediate these interactions. Frizzled-7 (fzd7) is expressed during gastrulation in the mesodermal cells fated to become heart, and then in the primary heart field. This expression is complementary to the expression of wnt11 and wnt11-R. We further show co-localisation of fzd7 with other early- and late-heart-specific markers using double in situ hybridisation. We have used loss of function analysis to determine the role of fzd7 during heart development. Morpholino antisense oligonucleotide-mediated knockdown of Fzd7 results in effects on heart development, similar to that caused by Wnt11 loss of function. Surprisingly, overexpression of dominant-negative Fzd7 cysteine rich domain (Fzd7 CRD) results in a cardia bifida phenotype, similar to the loss of wnt11-R phenotype. Overexpression of Fzd7 and activation of non-canonical wnt signalling can rescue the effect of Fzd7 CRD. We propose that Fzd7 has an important role during Xenopus heart development. Summary: Wnt signalling has been shown to be important in heart development. Here, we demonstrate that the wnt receptor fzd7 is required in mediating these Wnt signals.
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Affiliation(s)
- Muhammad Abu-Elmagd
- Center of Excellence in Genomic Medicine Research, King Abdulaziz University, P.O. Box 80216 Jeddah 21589, Kingdom of Saudi Arabia.,School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich, NR4 7TJ, UK
| | - Joanna Mulvaney
- School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich, NR4 7TJ, UK
| | - Grant N Wheeler
- School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich, NR4 7TJ, UK
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4
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Parikh A, Wu J, Blanton RM, Tzanakakis ES. Signaling Pathways and Gene Regulatory Networks in Cardiomyocyte Differentiation. TISSUE ENGINEERING PART B-REVIEWS 2015; 21:377-92. [PMID: 25813860 DOI: 10.1089/ten.teb.2014.0662] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Strategies for harnessing stem cells as a source to treat cell loss in heart disease are the subject of intense research. Human pluripotent stem cells (hPSCs) can be expanded extensively in vitro and therefore can potentially provide sufficient quantities of patient-specific differentiated cardiomyocytes. Although multiple stimuli direct heart development, the differentiation process is driven in large part by signaling activity. The engineering of hPSCs to heart cell progeny has extensively relied on establishing proper combinations of soluble signals, which target genetic programs thereby inducing cardiomyocyte specification. Pertinent differentiation strategies have relied as a template on the development of embryonic heart in multiple model organisms. Here, information on the regulation of cardiomyocyte development from in vivo genetic and embryological studies is critically reviewed. A fresh interpretation is provided of in vivo and in vitro data on signaling pathways and gene regulatory networks (GRNs) underlying cardiopoiesis. The state-of-the-art understanding of signaling pathways and GRNs presented here can inform the design and optimization of methods for the engineering of tissues for heart therapies.
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Affiliation(s)
- Abhirath Parikh
- 1 Lonza Walkersville, Inc. , Lonza Group, Walkersville, Maryland
| | - Jincheng Wu
- 2 Department of Chemical and Biological Engineering, Tufts University , Medford, Massachusetts
| | - Robert M Blanton
- 3 Division of Cardiology, Molecular Cardiology Research Institute , Tufts Medical Center, Tufts School of Medicine, Boston, Massachusetts
| | - Emmanuel S Tzanakakis
- 2 Department of Chemical and Biological Engineering, Tufts University , Medford, Massachusetts.,4 Tufts Clinical and Translational Science Institute (CTSI) , Boston, Massachusetts
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5
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Killick R, Ribe EM, Al-Shawi R, Malik B, Hooper C, Fernandes C, Dobson R, Nolan PM, Lourdusamy A, Furney S, Lin K, Breen G, Wroe R, To AWM, Leroy K, Causevic M, Usardi A, Robinson M, Noble W, Williamson R, Lunnon K, Kellie S, Reynolds CH, Bazenet C, Hodges A, Brion JP, Stephenson J, Paul Simons J, Lovestone S. Clusterin regulates β-amyloid toxicity via Dickkopf-1-driven induction of the wnt-PCP-JNK pathway. Mol Psychiatry 2014; 19:88-98. [PMID: 23164821 PMCID: PMC3873038 DOI: 10.1038/mp.2012.163] [Citation(s) in RCA: 174] [Impact Index Per Article: 17.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/08/2012] [Revised: 10/02/2012] [Accepted: 10/09/2012] [Indexed: 02/01/2023]
Abstract
Although the mechanism of Aβ action in the pathogenesis of Alzheimer's disease (AD) has remained elusive, it is known to increase the expression of the antagonist of canonical wnt signalling, Dickkopf-1 (Dkk1), whereas the silencing of Dkk1 blocks Aβ neurotoxicity. We asked if clusterin, known to be regulated by wnt, is part of an Aβ/Dkk1 neurotoxic pathway. Knockdown of clusterin in primary neurons reduced Aβ toxicity and DKK1 upregulation and, conversely, Aβ increased intracellular clusterin and decreased clusterin protein secretion, resulting in the p53-dependent induction of DKK1. To further elucidate how the clusterin-dependent induction of Dkk1 by Aβ mediates neurotoxicity, we measured the effects of Aβ and Dkk1 protein on whole-genome expression in primary neurons, finding a common pathway suggestive of activation of wnt-planar cell polarity (PCP)-c-Jun N-terminal kinase (JNK) signalling leading to the induction of genes including EGR1 (early growth response-1), NAB2 (Ngfi-A-binding protein-2) and KLF10 (Krüppel-like factor-10) that, when individually silenced, protected against Aβ neurotoxicity and/or tau phosphorylation. Neuronal overexpression of Dkk1 in transgenic mice mimicked this Aβ-induced pathway and resulted in age-dependent increases in tau phosphorylation in hippocampus and cognitive impairment. Furthermore, we show that this Dkk1/wnt-PCP-JNK pathway is active in an Aβ-based mouse model of AD and in AD brain, but not in a tau-based mouse model or in frontotemporal dementia brain. Thus, we have identified a pathway whereby Aβ induces a clusterin/p53/Dkk1/wnt-PCP-JNK pathway, which drives the upregulation of several genes that mediate the development of AD-like neuropathologies, thereby providing new mechanistic insights into the action of Aβ in neurodegenerative diseases.
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Affiliation(s)
- R Killick
- King's College London, Institute of Psychiatry, London, UK
| | - E M Ribe
- King's College London, Institute of Psychiatry, London, UK
| | - R Al-Shawi
- Division of Medicine and Centre for Biomedical Science, University College London, London, UK
| | - B Malik
- King's College London, Institute of Psychiatry, London, UK
| | - C Hooper
- King's College London, Institute of Psychiatry, London, UK
| | - C Fernandes
- King's College London, Institute of Psychiatry, London, UK
| | - R Dobson
- King's College London, Institute of Psychiatry, London, UK
| | - P M Nolan
- MRC Harwell, Mammalian Genetics Unit, Harwell Science and Innovation Campus, Oxfordshire, UK
| | - A Lourdusamy
- King's College London, Institute of Psychiatry, London, UK
| | - S Furney
- King's College London, Institute of Psychiatry, London, UK
| | - K Lin
- King's College London, Institute of Psychiatry, London, UK
| | - G Breen
- King's College London, Institute of Psychiatry, London, UK
| | - R Wroe
- King's College London, Institute of Psychiatry, London, UK
| | - A W M To
- King's College London, Institute of Psychiatry, London, UK
| | - K Leroy
- Université Libre de Bruxelles, Faculté de Médecine, Brussels, Belgium
| | - M Causevic
- King's College London, Institute of Psychiatry, London, UK
| | - A Usardi
- King's College London, Institute of Psychiatry, London, UK
| | - M Robinson
- King's College London, Institute of Psychiatry, London, UK
| | - W Noble
- King's College London, Institute of Psychiatry, London, UK
| | - R Williamson
- King's College London, Institute of Psychiatry, London, UK
| | - K Lunnon
- Division of Medicine and Centre for Biomedical Science, University College London, London, UK
| | - S Kellie
- University of Queensland, School of Chemistry and Molecular Biosciences, Brisbane, Queensland, Australia
| | - C H Reynolds
- King's College London, Institute of Psychiatry, London, UK
| | - C Bazenet
- King's College London, Institute of Psychiatry, London, UK
| | - A Hodges
- King's College London, Institute of Psychiatry, London, UK
| | - J-P Brion
- Université Libre de Bruxelles, Faculté de Médecine, Brussels, Belgium
| | - J Stephenson
- King's College London, Institute of Psychiatry, London, UK
| | - J Paul Simons
- Division of Medicine and Centre for Biomedical Science, University College London, London, UK
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6
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Chaitra K, Ulaganathan K, James A, Ananthapur V, Nallari P. miRNA regulation during cardiac development and remodeling in cardiomyopathy. EXCLI JOURNAL 2013; 12:980-92. [PMID: 27092038 PMCID: PMC4827073] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/23/2013] [Accepted: 11/07/2013] [Indexed: 12/03/2022]
Abstract
miRNAs have been found to play a major role in cardiomyopathy, a heart muscle disorder characterized by cardiac dysfunction. Several miRNAs including those involved in heart development are found to be dysregulated in cardiomyopathy. These miRNAs act either directly or indirectly by controlling the genes involved in normal development and functioning of the heart. Indirectly it also targets modifier genes and genes involved in signaling pathways. In this review, miRNAs involved in heart development, including dysregulation of miRNA which regulate various genes, modifiers and notch signaling pathway genes leading to cardiomyopathy are discussed. A study of these miRNAs would give an insight into the mechanisms involved in the processes of heart development and disease. Apart from this, information gathered from these studies would also generate suitable therapeutic targets in the form of antagomirs which are chemically engineered oligonucleotides used for silencing miRNAs.
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Affiliation(s)
- K.L. Chaitra
- Department of Genetics, Osmania University, Hyderabad, India
| | | | - Anita James
- Department of Genetics, Osmania University, Hyderabad, India
| | | | - Pratibha Nallari
- Department of Genetics, Osmania University, Hyderabad, India,*To whom correspondence should be addressed: Pratibha Nallari, Department of Genetics, Osmania University, Hyderabad, India, E-mail:
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7
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Cheng SL, Shao JS, Behrmann A, Krchma K, Towler DA. Dkk1 and MSX2-Wnt7b signaling reciprocally regulate the endothelial-mesenchymal transition in aortic endothelial cells. Arterioscler Thromb Vasc Biol 2013; 33:1679-89. [PMID: 23685555 PMCID: PMC3837473 DOI: 10.1161/atvbaha.113.300647] [Citation(s) in RCA: 85] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2012] [Accepted: 04/25/2013] [Indexed: 01/28/2023]
Abstract
OBJECTIVE Endothelial cells (ECs) can undergo an endothelial-mesenchymal transition with tissue fibrosis. Wnt- and Msx2-regulated signals participate in arteriosclerotic fibrosis and calcification. We studied the impact of Wnt7, Msx2, and Dkk1, a Wnt7 antagonist, on endothelial-mesenchymal transition in primary aortic ECs. APPROACH AND RESULTS Transduction of aortic ECs with vectors expressing Dkk1 suppressed EC differentiation and induced a mineralizing myofibroblast phenotype. Dkk1 suppressed claudin 5, PECAM, cadherin 5 (Cdh5), Tie1, and Tie2. Dkk1 converted the cuboidal cell monolayer into a spindle-shaped multilayer and inhibited EC cord formation. Myofibroblast and osteogenic markers, SM22, type I collagen, Osx, Runx2, and alkaline phosphatase, were upregulated by Dkk1 via activin-like kinase/Smad pathways. Dkk1 increased fibrotic mineralization of aortic ECs cultured under osteogenic conditions--the opposite of mesenchymal cell responses. Msx2 and Wnt7b maintained morphology and upregulated markers of differentiated ECs. Deleting EC Wnt7b with the Cdh5-Cre transgene in Wnt7b(fl/fl);LDLR(-/-) mice upregulated aortic osteogenic genes (Osx, Sox9, Runx2, and Msx2) and nuclear phospho-Smad1/5, and increased collagen and calcium accumulation. CONCLUSIONS Dkk1 enhances endothelial-mesenchymal transition in aortic ECs, whereas Wnt7b and Msx2 signals preserve EC phenotype. EC responses to Dkk1, Wnt7b, and Msx2 are the opposite of mesenchymal responses, coupling EC phenotypic stability with osteofibrogenic predilection during arteriosclerosis.
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MESH Headings
- Animals
- Antigens, CD/genetics
- Antigens, CD/metabolism
- Aorta/metabolism
- Aorta/pathology
- Aortic Diseases/genetics
- Aortic Diseases/metabolism
- Aortic Diseases/pathology
- Arteriosclerosis/genetics
- Arteriosclerosis/metabolism
- Arteriosclerosis/pathology
- Biomarkers/metabolism
- Cadherins/genetics
- Cadherins/metabolism
- Cattle
- Cell Differentiation
- Cell Shape
- Cells, Cultured
- Disease Models, Animal
- Endothelial Cells/metabolism
- Endothelial Cells/pathology
- Epithelial-Mesenchymal Transition
- Fibrosis
- Gene Expression Regulation
- Homeodomain Proteins/genetics
- Homeodomain Proteins/metabolism
- Intercellular Signaling Peptides and Proteins/genetics
- Intercellular Signaling Peptides and Proteins/metabolism
- Male
- Mice
- Mice, Knockout
- Myofibroblasts/metabolism
- Myofibroblasts/pathology
- Neovascularization, Physiologic
- Ossification, Heterotopic/metabolism
- Phenotype
- Receptors, LDL/genetics
- Receptors, LDL/metabolism
- Transduction, Genetic
- Transfection
- Wnt Proteins/deficiency
- Wnt Proteins/genetics
- Wnt Proteins/metabolism
- Wnt Signaling Pathway
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Affiliation(s)
- Su-Li Cheng
- Diabetes and Obesity Research Center, Sanford-Burnham Medical Research Institute, Orlando, FL 32827
| | - Jian-Su Shao
- Department of Internal Medicine, Washington University, St. Louis, Missouri 63110
| | - Abraham Behrmann
- Diabetes and Obesity Research Center, Sanford-Burnham Medical Research Institute, Orlando, FL 32827
| | - Karen Krchma
- Diabetes and Obesity Research Center, Sanford-Burnham Medical Research Institute, Orlando, FL 32827
| | - Dwight A. Towler
- Diabetes and Obesity Research Center, Sanford-Burnham Medical Research Institute, Orlando, FL 32827
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8
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Reis M, Liebner S. Wnt signaling in the vasculature. Exp Cell Res 2013; 319:1317-23. [PMID: 23291327 DOI: 10.1016/j.yexcr.2012.12.023] [Citation(s) in RCA: 144] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2012] [Revised: 12/20/2012] [Accepted: 12/21/2012] [Indexed: 12/21/2022]
Abstract
The development of the vascular system requires orchestrated activities of various molecular pathways to assure the formation of a hierarchically branched tubular network. Furthermore, endothelial cell (EC) populations are heterogeneous to meet organ-specific requirements in the mature vasculature. This developmental scheme is probably best represented by the acquisition and maintenance of unique barrier properties known as the blood-brain barrier (BBB) in microvessels of the central nervous system (CNS). Only recently, the canonical Wnt/β-catenin pathway was implicated in many aspects of angiogenesis, vascular remodeling and differentiation in various species and organ systems. Beside its major contribution to brain angiogenesis and barrier formation, the Wnt/β-catenin pathway influences vascular sprouting, remodeling and arterio-venous specification by modulating the Notch pathway. Furthermore, canonical Wnt signaling has been implicated in heart valve formation by initiating endothelial-mesenchymal transition. Growing evidence also points to a role of the non-canonical Wnt pathway in vascular development by regulating VEGF availability. Several novel findings regarding the role of the Wnt pathway in developmental as well as in pathological angiogenesis prompted us to review its emerging function in the vasculature.
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Affiliation(s)
- Marco Reis
- Institute of Neurology (Edinger-Institute), Johann Wolfgang Goethe-University Frankfurt Medical School, Heinrich-Hoffmann-Straße 7, 60528 Frankfurt, Germany
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9
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Marinou K, Christodoulides C, Antoniades C, Koutsilieris M. Wnt signaling in cardiovascular physiology. Trends Endocrinol Metab 2012; 23:628-36. [PMID: 22902904 DOI: 10.1016/j.tem.2012.06.001] [Citation(s) in RCA: 95] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/09/2012] [Revised: 06/01/2012] [Accepted: 06/04/2012] [Indexed: 01/17/2023]
Abstract
Wnt signaling pathways play a key role in cardiac development, angiogenesis, and cardiac hypertrophy; emerging evidence suggests that they are also involved in the pathophysiology of atherosclerosis. Specifically, an important role for Wnts has been described in the regulation of endothelial inflammation, vascular calcification, and mesenchymal stem cell differentiation. Wnt signaling also induces monocyte adhesion to endothelial cells and is crucial for the regulation of vascular smooth-muscle cell (VSMC) behavior. We discuss how the Wnt pathways are implicated in vascular biology and outline the role of Wnt signaling in atherosclerosis. Dissecting Wnt pathways involved in atherogenesis and cardiovascular disease may provide crucial insights into novel mechanisms with therapeutic potential for atherosclerosis.
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Affiliation(s)
- K Marinou
- Department of Physiology, Athens University Medical School, Athens, Greece.
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10
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Korvala J, Löija M, Mäkitie O, Sochett E, Jüppner H, Schnabel D, Mora S, Cole WG, Ala-Kokko L, Männikkö M. Rare variations in WNT3A and DKK1 may predispose carriers to primary osteoporosis. Eur J Med Genet 2012; 55:515-9. [DOI: 10.1016/j.ejmg.2012.06.011] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2012] [Accepted: 06/21/2012] [Indexed: 12/30/2022]
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11
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Tanaka SS, Kojima Y, Yamaguchi YL, Nishinakamura R, Tam PPL. Impact of WNT signaling on tissue lineage differentiation in the early mouse embryo. Dev Growth Differ 2011; 53:843-56. [PMID: 21762130 DOI: 10.1111/j.1440-169x.2011.01292.x] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
WNT signaling activity is involved in the regulation of many cellular functions, including proliferation, migration, cell fate specification, maintenance of pluripotency and induction of tumorigenicity. Here we summarize recent progress towards understanding the regulation of canonical WNT/β-catenin signaling activity through feedback regulatory loops involving the ligands, agonists and antagonists, the availability of intracellular pools of active β-catenin and the cross-regulation of the WNT activity by β-catenin independent pathway. We also review recent findings on the role of WNT/β-catenin signaling in tissue lineage differentiation during embryogenesis and the maintenance and self renewal of embryo-derived stem cells in vitro.
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Affiliation(s)
- Satomi S Tanaka
- Department of Kidney Development, Institute of Molecular Embryology and Genetics, Kumamoto University, Kumamoto, Japan.
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12
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Liu W, Foley AC. Signaling pathways in early cardiac development. WILEY INTERDISCIPLINARY REVIEWS-SYSTEMS BIOLOGY AND MEDICINE 2011; 3:191-205. [PMID: 20830688 DOI: 10.1002/wsbm.112] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Cardiomyocyte differentiation is a complex multistep process requiring the proper temporal and spatial integration of multiple signaling pathways. Previous embryological and genetic studies have identified a number of signaling pathways that are critical to mediate the initial formation of the mesoderm and its allocation to the cardiomyocyte lineage. It has become clear that some of these signaling networks work autonomously, in differentiating myocardial cells whereas others work non-autonomously, in neighboring tissues, to regulate cardiac differentiation indirectly. Here, we provide an overview of three signaling networks that mediate cardiomyocyte specification and review recent insights into their specific roles in heart development. In addition, we demonstrate how systems level, 'omic approaches' and other high-throughput techniques such as small molecules screens are beginning to impact our understanding of cardiomyocyte specification and, to identify novel signaling pathways involved in this process. In particular, it now seems clear that at least one chemokine receptor CXCR4 is an important marker for cardiomyocyte progenitors and may play a functional role in their differentiation. Finally, we discuss some gaps in our current understanding of early lineage selection that could be addressed by various types of omic analysis.
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Affiliation(s)
- Wenrui Liu
- Greenberg Division of Cardiology, Department of Medicine, Weill Medical College of Cornell University, New York, NY, USA
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13
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Direct differentiation of atrial and ventricular myocytes from human embryonic stem cells by alternating retinoid signals. Cell Res 2010; 21:579-87. [PMID: 21102549 DOI: 10.1038/cr.2010.163] [Citation(s) in RCA: 250] [Impact Index Per Article: 17.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Although myocyte cell transplantation studies have suggested a promising therapeutic potential for myocardial infarction, a major obstacle to the development of clinical therapies for myocardial repair is the difficulties associated with obtaining relatively homogeneous ventricular myocytes for transplantation. Human embryonic stem cells (hESCs) are a promising source of cardiomyocytes. Here we report that retinoid signaling regulates the fate specification of atrial versus ventricular myocytes during cardiac differentiation of hESCs. We found that both Noggin and the pan-retinoic acid receptor antagonist BMS-189453 (RAi) significantly increased the cardiac differentiation efficiency of hESCs. To investigate retinoid functions, we compared Noggin+RAi-treated cultures with Noggin+RA-treated cultures. Our results showed that the expression levels of the ventricular-specific gene IRX-4 were radically elevated in Noggin+RAi-treated cultures. MLC-2V, another ventricular-specific marker, was expressed in the majority of the cardiomyocytes in Noggin+RAi-treated cultures, but not in the cardiomyocytes of Noggin+RA-treated cultures. Flow cytometry analysis and electrophysiological studies indicated that with 64.7 ± 0.88% (mean ±s.e.m) cardiac differentiation efficiency, 83% of the cardiomyocytes in Noggin+RAi-treated cultures had embryonic ventricular-like action potentials (APs). With 50.7 ± 1.76% cardiac differentiation efficiency, 94% of the cardiomyocytes in Noggin+RA-treated cultures had embryonic atrial-like APs. These results were further confirmed by imaging studies that assessed the patterns and properties of the Ca(2+) sparks of the cardiomyocytes from the two cultures. These findings demonstrate that retinoid signaling specifies the atrial versus ventricular differentiation of hESCs. This study also shows that relatively homogeneous embryonic atrial- and ventricular-like myocyte populations can be efficiently derived from hESCs by specifically regulating Noggin and retinoid signals.
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14
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Sotoodehnia N, Isaacs A, de Bakker PIW, Dörr M, Newton-Cheh C, Nolte IM, van der Harst P, Müller M, Eijgelsheim M, Alonso A, Hicks AA, Padmanabhan S, Hayward C, Smith AV, Polasek O, Giovannone S, Fu J, Magnani JW, Marciante KD, Pfeufer A, Gharib SA, Teumer A, Li M, Bis JC, Rivadeneira F, Aspelund T, Köttgen A, Johnson T, Rice K, Sie MPS, Wang YA, Klopp N, Fuchsberger C, Wild SH, Mateo Leach I, Estrada K, Völker U, Wright AF, Asselbergs FW, Qu J, Chakravarti A, Sinner MF, Kors JA, Petersmann A, Harris TB, Soliman EZ, Munroe PB, Psaty BM, Oostra BA, Cupples LA, Perz S, de Boer RA, Uitterlinden AG, Völzke H, Spector TD, Liu FY, Boerwinkle E, Dominiczak AF, Rotter JI, van Herpen G, Levy D, Wichmann HE, van Gilst WH, Witteman JCM, Kroemer HK, Kao WHL, Heckbert SR, Meitinger T, Hofman A, Campbell H, Folsom AR, van Veldhuisen DJ, Schwienbacher C, O'Donnell CJ, Volpato CB, Caulfield MJ, Connell JM, Launer L, Lu X, Franke L, Fehrmann RSN, te Meerman G, Groen HJM, Weersma RK, van den Berg LH, Wijmenga C, Ophoff RA, Navis G, Rudan I, Snieder H, Wilson JF, Pramstaller PP, Siscovick DS, Wang TJ, Gudnason V, van Duijn CM, Felix SB, Fishman GI, Jamshidi Y, Stricker BHC, Samani NJ, Kääb S, Arking DE. Common variants in 22 loci are associated with QRS duration and cardiac ventricular conduction. Nat Genet 2010; 42:1068-76. [PMID: 21076409 PMCID: PMC3338195 DOI: 10.1038/ng.716] [Citation(s) in RCA: 264] [Impact Index Per Article: 18.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2010] [Accepted: 10/19/2010] [Indexed: 12/16/2022]
Abstract
QRS interval on the electrocardiogram reflects ventricular depolarization and conduction time, and is a risk factor for mortality, sudden death, and heart failure. We performed a genome-wide association meta-analysis in 40,407 European-descent individuals from 14 studies, with further genotyping in 7170 additional Europeans, and identified 22 loci associated with QRS duration (P < 5 × 10−8). These loci map in or near genes in pathways with established roles in ventricular conduction such as sodium channels, transcription factors, and calcium-handling proteins, but also point to novel biologic processes, such as kinase inhibitors and genes related to tumorigenesis. We demonstrate that SCN10A, a gene at our most significant locus, is expressed in the mouse ventricular conduction system, and treatment with a selective SCN10A blocker prolongs QRS duration. These findings extend our current knowledge of ventricular depolarization and conduction.
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Affiliation(s)
- Nona Sotoodehnia
- Division of Cardiology, Department of Medicine, University of Washington, Seattle, Washington, USA.
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15
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Liu C, Gao H, Zhai S, Liu B. Molecular characterization, chromosomal localization, expression profile and association analysis with carcass traits of the porcine dickkopf homolog1 gene. Mol Biol Rep 2010; 38:1929-34. [DOI: 10.1007/s11033-010-0313-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2010] [Accepted: 09/03/2010] [Indexed: 11/28/2022]
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16
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Gessert S, Kühl M. The multiple phases and faces of wnt signaling during cardiac differentiation and development. Circ Res 2010; 107:186-99. [PMID: 20651295 DOI: 10.1161/circresaha.110.221531] [Citation(s) in RCA: 293] [Impact Index Per Article: 20.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Understanding heart development on a molecular level is a prerequisite for uncovering the causes of congenital heart diseases. Therapeutic approaches that try to enhance cardiac regeneration or that involve the differentiation of resident cardiac progenitor cells or patient-specific induced pluripotent stem cells will also benefit tremendously from this knowledge. Wnt proteins have been shown to play multiple roles during cardiac differentiation and development. They are extracellular growth factors that activate different intracellular signaling branches. Here, we summarize our current understanding of how these factors affect different aspects of cardiogenesis, starting from early specification of cardiac progenitors and continuing on to later developmental steps, such as morphogenetic processes, valve formation, and establishment of the conduction system.
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Affiliation(s)
- Susanne Gessert
- Institute for Biochemistry and Molecular Biology, Ulm University, Albert-Einstein-Allee 11, D-89081 Ulm, Germany
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17
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Abstract
Growth factor signaling is required for cellular differentiation, tissue morphogenesis, and tissue homeostasis. Misregulation of intracellular signal transduction can lead to developmental defects during embryogenesis or particular diseases in the adult. One family of growth factors important for these aspects is given by the Wnt proteins. In particular, Wnts have important functions in stem cell biology, cardiac development and differentiation, angiogenesis, cardiac hypertrophy, cardiac failure, and aging. Knowledge of growth factor signaling during differentiation will allow for improvement of targeted differentiation of embryonic or adult stem cells toward functional cardiomyocytes or for understanding the basis of diseases. Our major aim here is to provide a state of the art review summarizing our present knowledge of the intracellular Wnt-mediated signaling network. In particular, we provide evidence that the subdivision into canonical and noncanonical Wnt signaling pathways solely based on the identity of Wnt ligands or Frizzled receptors is not appropriate anymore. We thereby deliver a solid base for further upcoming articles of a review series focusing on the role of Wnt proteins on different aspects of cardiovascular development and dysfunction.
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Affiliation(s)
- Tata Purushothama Rao
- Institute for Biochemistry and Molecular Biology, Ulm University, Albert-Einstein-Allee 11, D-89081 Ulm, Germany
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18
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Ji YR, Kim MO, Kim SH, Yu DH, Shin MJ, Kim HJ, Yuh HS, Bae KB, Kim JY, Park HD, Lee SG, Hyun BH, Ryoo ZY. Effects of regulator of G protein signaling 19 (RGS19) on heart development and function. J Biol Chem 2010; 285:28627-34. [PMID: 20562099 DOI: 10.1074/jbc.m109.073718] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Wnt/Wg genes play a critical role in the development of various organisms. For example, the Wnt/beta-catenin signal promotes heart formation and cardiomyocyte differentiation in mice. Previous studies have shown that RGS19 (regulator of G protein signaling 19), which has Galpha subunits with GTPase activity, inhibits the Wnt/beta-catenin signal through inactivation of Galpha(o). In the present study, the effects of RGS19 on mouse cardiac development were observed. In P19 teratocarcinoma cells with RGS19 overexpression, RGS19 inhibited cardiomyocyte differentiation by blocking the Wnt signal. Additionally, several genes targeted by Wnt were down-regulated. For the in vivo study, we generated RGS19-overexpressing transgenic (RGS19 TG) mice. In these transgenic mice, septal defects and thin-walled ventricles were observed during the embryonic phase of development, and the expression of cardiogenesis-related genes, BMP4 and Mef2C, was reduced significantly. RGS19 TG mice showed increased expression levels of brain natriuretic peptide and beta-MHC, which are markers of heart failure, increase of cell proliferation, and electrocardiogram analysis shows abnormal ventricle repolarization. These data provide in vitro and in vivo evidence that RGS19 influenced cardiac development and had negative effects on heart function.
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Affiliation(s)
- Young Rae Ji
- School of Life Science and Biotechnology, Kyungpook National University, 1370 Sankyuk-dong, Buk-ku, Daegu 702-701, Korea
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19
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Sato N, Yamabuki T, Takano A, Koinuma J, Aragaki M, Masuda K, Ishikawa N, Kohno N, Ito H, Miyamoto M, Nakayama H, Miyagi Y, Tsuchiya E, Kondo S, Nakamura Y, Daigo Y. Wnt inhibitor Dickkopf-1 as a target for passive cancer immunotherapy. Cancer Res 2010; 70:5326-36. [PMID: 20551066 DOI: 10.1158/0008-5472.can-09-3879] [Citation(s) in RCA: 124] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Dickkopf-1 (DKK1) is an inhibitor of Wnt/beta-catenin signaling that is overexpressed in most lung and esophageal cancers. Here, we show its utility as a serum biomarker for a wide range of human cancers, and we offer evidence favoring the potential application of anti-DKK1 antibodies for cancer treatment. Using an original ELISA system, high levels of DKK1 protein were found in serologic samples from 906 patients with cancers of the pancreas, stomach, liver, bile duct, breast, and cervix, which also showed elevated expression levels of DKK1. Additionally, anti-DKK1 antibody inhibited the invasive activity and the growth of cancer cells in vitro and suppressed the growth of engrafted tumors in vivo. Tumor tissues treated with anti-DKK1 displayed significant fibrotic changes and a decrease in viable cancer cells without apparent toxicity in mice. Our findings suggest DKK1 as a serum biomarker for screening against a variety of cancers, and anti-DKK1 antibodies as potential theranostic tools for diagnosis and treatment of cancer.
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Affiliation(s)
- Nagato Sato
- Laboratory of Molecular Medicine, Human Genome Center, Institute of Medical Science, The University of Tokyo, Tokyo, Japan
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20
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Samuel LJ, Latinkić BV. Early activation of FGF and nodal pathways mediates cardiac specification independently of Wnt/beta-catenin signaling. PLoS One 2009; 4:e7650. [PMID: 19862329 PMCID: PMC2763344 DOI: 10.1371/journal.pone.0007650] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2009] [Accepted: 10/07/2009] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Cardiac induction, the first step in heart development in vertebrate embryos, is thought to be initiated by anterior endoderm during gastrulation, but what the signals are and how they act is unknown. Several signaling pathways, including FGF, Nodal, BMP and Wnt have been implicated in cardiac specification, in both gain- and loss-of-function experiments. However, as these pathways regulate germ layer formation and patterning, their specific roles in cardiac induction have been difficult to define. METHODOLOGY/PRINCIPAL FINDINGS To investigate the mechanisms of cardiac induction directly we devised an assay based on conjugates of anterior endoderm from early gastrula stage Xenopus embryos as the inducing tissue and pluripotent ectodermal explants as the responding tissue. We show that the anterior endoderm produces a specific signal, as skeletal muscle is not induced. Cardiac inducing signal needs up to two hours of interaction with the responding tissue to produce an effect. While we found that the BMP pathway was not necessary, our results demonstrate that the FGF and Nodal pathways are essential for cardiogenesis. They were required only during the first hour of cardiogenesis, while sustained activation of ERK was required for at least four hours. Our results also show that transient early activation of the Wnt/beta-catenin pathway has no effect on cardiogenesis, while later activation of the pathway antagonizes cardiac differentiation. CONCLUSIONS/SIGNIFICANCE We have described an assay for investigating the mechanisms of cardiac induction by anterior endoderm. The assay was used to provide evidence for a direct, early and transient requirement of FGF and Nodal pathways. In addition, we demonstrate that Wnt/beta-catenin pathway plays no direct role in vertebrate cardiac specification, but needs to be suppressed just prior to differentiation.
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Affiliation(s)
- Lee J. Samuel
- School of Biosciences, Cardiff University, Cardiff, United Kingdom
| | - Branko V. Latinkić
- School of Biosciences, Cardiff University, Cardiff, United Kingdom
- * E-mail:
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Koch S, Capaldo CT, Samarin S, Nava P, Neumaier I, Skerra A, Sacks DB, Parkos CA, Nusrat A. Dkk-1 inhibits intestinal epithelial cell migration by attenuating directional polarization of leading edge cells. Mol Biol Cell 2009; 20:4816-25. [PMID: 19776352 DOI: 10.1091/mbc.e09-05-0415] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Wnt signaling pathways regulate proliferation, motility, and survival in a variety of human cell types. Dickkopf-1 (Dkk-1) is a secreted Wnt antagonist that has been proposed to regulate tissue homeostasis in the intestine. In this report, we show that Dkk-1 is secreted by intestinal epithelial cells after wounding and that it inhibits cell migration by attenuating the directional orientation of migrating epithelial cells. Dkk-1 exposure induced mislocalized activation of Cdc42 in migrating cells, which coincided with a displacement of the polarity protein Par6 from the leading edge. Consequently, the relocation of the microtubule organizing center and the Golgi apparatus in the direction of migration was significantly and persistently inhibited in the presence of Dkk-1. Small interfering RNA-induced down-regulation of Dkk-1 confirmed that extracellular exposure to Dkk-1 was required for this effect. Together, these data demonstrate a novel role of Dkk-1 in the regulation of directional polarization of migrating intestinal epithelial cells, which contributes to the effect of Dkk-1 on wound closure in vivo.
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Affiliation(s)
- Stefan Koch
- Epithelial Pathobiology Unit, Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, GA 30322, USA
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22
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Willems E, Bushway PJ, Mercola M. Natural and synthetic regulators of embryonic stem cell cardiogenesis. Pediatr Cardiol 2009; 30:635-42. [PMID: 19319460 PMCID: PMC3478151 DOI: 10.1007/s00246-009-9409-2] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/01/2009] [Accepted: 03/03/2009] [Indexed: 12/24/2022]
Abstract
Debilitating cardiomyocyte loss underlies the progression to heart failure. Although there have been significant advances in treatment, current therapies are intended to improve or preserve heart function rather than regenerate lost myocardium. A major hurdle in implementing a cell-based regenerative therapy is the inefficient differentiation of cardiomyocytes from either endogenous or exogenous stem cell sources. Moreover, cardiomyocytes that develop in human embryonic stem cell (hESC) or human-induced pluripotent stem cell (hIPSC) cultures are comparatively immature, even after prolonged culture, and differences in their calcium handling, ion channel, and force generation properties relative to adult cardiomyocytes raise concerns of improper integration and function after transplantation. Thus, the discovery of natural and novel small molecule synthetic regulators of differentiation and maturation would accelerate the development of stem-cell-based myocardial therapies. Here, we document recent advances in defining natural signaling pathways that direct the multistep cardiomyogenic differentiation program and the development of small molecules that might be used to enhance differentiation as well as the potential characteristics of lead candidates for pharmaceutical stimulation of endogenous myocardial replacement.
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