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Möser C, Lorenz JS, Sajfutdinow M, Smith DM. Pinpointed Stimulation of EphA2 Receptors via DNA-Templated Oligovalence. Int J Mol Sci 2018; 19:ijms19113482. [PMID: 30404153 PMCID: PMC6274923 DOI: 10.3390/ijms19113482] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2018] [Accepted: 11/02/2018] [Indexed: 11/20/2022] Open
Abstract
DNA nanostructures enable the attachment of functional molecules to nearly any unique location on their underlying structure. Due to their single-base-pair structural resolution, several ligands can be spatially arranged and closely controlled according to the geometry of their desired target, resulting in optimized binding and/or signaling interactions. Here, the efficacy of SWL, an ephrin-mimicking peptide that binds specifically to EphrinA2 (EphA2) receptors, increased by presenting up to three of these peptides on small DNA nanostructures in an oligovalent manner. Ephrin signaling pathways play crucial roles in tumor development and progression. Moreover, Eph receptors are potential targets in cancer diagnosis and treatment. Here, the quantitative impact of SWL valency on binding, phosphorylation (key player for activation) and phenotype regulation in EphA2-expressing prostate cancer cells was demonstrated. EphA2 phosphorylation was significantly increased by DNA trimers carrying three SWL peptides compared to monovalent SWL. In comparison to one of EphA2’s natural ligands ephrin-A1, which is known to bind promiscuously to multiple receptors, pinpointed targeting of EphA2 by oligovalent DNA-SWL constructs showed enhanced cell retraction. Overall, we show that DNA scaffolds can increase the potency of weak signaling peptides through oligovalent presentation and serve as potential tools for examination of complex signaling pathways.
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Affiliation(s)
- Christin Möser
- DNA Nanodevices Unit, Department Diagnostics, Fraunhofer Institute for Cell Therapy and Immunology IZI, 04103 Leipzig, Germany.
- Institute of Biochemistry and Biology, Faculty of Science, University of Potsdam, 14476 Potsdam, Germany.
| | - Jessica S Lorenz
- DNA Nanodevices Unit, Department Diagnostics, Fraunhofer Institute for Cell Therapy and Immunology IZI, 04103 Leipzig, Germany.
- Peter Debye Institute for Soft Matter Physics, Faculty of Physics and Earth Sciences, University of Leipzig, 04103 Leipzig, Germany.
| | - Martin Sajfutdinow
- DNA Nanodevices Unit, Department Diagnostics, Fraunhofer Institute for Cell Therapy and Immunology IZI, 04103 Leipzig, Germany.
- Fraunhofer Project Center "Microelectronic and Optical Systems for Biomedicine" (MEOS), 99099 Erfurt, Germany.
| | - David M Smith
- DNA Nanodevices Unit, Department Diagnostics, Fraunhofer Institute for Cell Therapy and Immunology IZI, 04103 Leipzig, Germany.
- Peter Debye Institute for Soft Matter Physics, Faculty of Physics and Earth Sciences, University of Leipzig, 04103 Leipzig, Germany.
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Wijeratne D, Rodger J, Stevenson A, Wallace H, Prêle CM, Wood FM, Fear MW. Ephrin-A2 affects wound healing and scarring in a murine model of excisional injury. Burns 2018; 45:682-690. [PMID: 30482614 DOI: 10.1016/j.burns.2018.10.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2018] [Revised: 09/14/2018] [Accepted: 10/04/2018] [Indexed: 12/18/2022]
Abstract
Ephrin ligand/Eph receptor signaling is important in both tissue development and homeostasis. There is increasing evidence that Ephrin/Eph signaling is important in the skin, involved in hair follicle cycling, epidermal differentiation, cutaneous innervation and skin cancer. However, there is currently limited information on the role of Ephrin/Eph signaling in cutaneous wound healing. Here we report the effects of the Ephrin-A2 and A5 ligands on wound healing. Using Ephrin-A2-/-, Ephrin-A5-/- and Ephrin-A2A5-/- transgenic mice, in vitro wound healing assays were conducted using isolated keratinocytes and fibroblasts. Ephrin-A2-/-, Ephrin-A2A5-/- and wild type mice with excisional wounds were used to analyze the impact of these ligands on wound closure, scar outcome, collagen orientation and re-innervation in vivo. The absence of the Ephrin-A2 and A5 ligands did not have any effect on dermal fibroblast proliferation or on fibroblast or keratinocyte migration. The loss of Ephrin-A2 and A5 ligands did not impact on the rate of wound closure or re-innervation after injury. However, changes in the gross morphology of the healed scar and in collagen histology of the scar dermis were observed in transgenic mice. Therefore Ephrin-A2 and A5 ligands may play an important role in final scar appearance associated with collagen deposition and structure.
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Affiliation(s)
- Dulharie Wijeratne
- Burn Injury Research Unit, School of Biomedical Sciences, The University of Western Australia, Australia
| | - Jennifer Rodger
- Experimental and Regenerative Neurosciences, School of Biological Sciences, The University of Western Australia, Australia
| | - Andrew Stevenson
- Burn Injury Research Unit, School of Biomedical Sciences, The University of Western Australia, Australia
| | - Hilary Wallace
- Burn Injury Research Unit, School of Biomedical Sciences, The University of Western Australia, Australia
| | - Cecilia M Prêle
- The Institute for Respiratory Health, The University of Western Australia, Nedlands, Western Australia, Australia; Centre for Cell Therapy and Regenerative Medicine, School of Biomedical Sciences, The University of Western Australia, Crawley, Western Australia, Australia
| | - Fiona M Wood
- Burn Injury Research Unit, School of Biomedical Sciences, The University of Western Australia, Australia; Centre for Cell Therapy and Regenerative Medicine, School of Biomedical Sciences, The University of Western Australia, Crawley, Western Australia, Australia; The Fiona Wood Foundation, Perth, Western Australia, Australia; Burns Service of Western Australia, WA Department of Health, Perth, Western Australia, Australia
| | - Mark W Fear
- Burn Injury Research Unit, School of Biomedical Sciences, The University of Western Australia, Australia; The Institute for Respiratory Health, The University of Western Australia, Nedlands, Western Australia, Australia; The Fiona Wood Foundation, Perth, Western Australia, Australia.
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Stallaert W, Brüggemann Y, Sabet O, Baak L, Gattiglio M, Bastiaens PIH. Contact inhibitory Eph signaling suppresses EGF-promoted cell migration by decoupling EGFR activity from vesicular recycling. Sci Signal 2018; 11:11/541/eaat0114. [DOI: 10.1126/scisignal.aat0114] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
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54
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Hamaoka Y, Negishi M, Katoh H. Tyrosine kinase activity of EphA2 promotes its S897 phosphorylation and glioblastoma cell proliferation. Biochem Biophys Res Commun 2018; 499:920-926. [DOI: 10.1016/j.bbrc.2018.04.020] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2018] [Accepted: 04/03/2018] [Indexed: 01/04/2023]
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Worku T, Wang K, Ayers D, Wu D, Ur Rehman Z, Zhou H, Yang L. Regulatory roles of ephrinA5 and its novel signaling pathway in mouse primary granulosa cell apoptosis and proliferation. Cell Cycle 2018; 17:892-902. [PMID: 29619874 DOI: 10.1080/15384101.2018.1456297] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Recent findings suggest that ephrinA5 (Efna5) has a novel role in female mouse fertility, in addition to its well-defined role as a neurogenesis factor. Nevertheless, its physiological roles in ovarian granulosa cells (GC) have not been determined. In this study, mouse GC were cultured and transfected with ephrin A5 siRNA and negative control to determine the effects of Efna5 on GC apoptosis, proliferation, cell cycle progression, and related signaling pathways. To understand the mode signaling, the mRNA expression levels of Efna5 receptors (Eph receptor A5, Eph receptor A3, Eph receptor A8, and Eph receptor B2) were examined. Both mRNA and protein expressions of apoptosis-related factors (Bax, Bcl-2, Caspase 8, Caspase 3, and Tnfα) and a proliferation marker, Pcna, were investigated. Additionally, the role of Efna5 on paracrine oocyte-secreted factors and steroidogenesis hormones were also explored. Efna5 silencing suppressed GC apoptosis by downregulating Bax and upregulating Bcl-2 in a Caspase 8-dependent manner. Efna5 knockdown promoted GC proliferation via p-Akt and p-ERK pathway activation. The inhibition of Efna5 enhanced BMH15 and estradiol expression, but suppressed GDF9, while progesterone level remained unaltered. These results demonstrated that Efna5 is a pro-apoptotic agent in GC and plays important role in folliculogenesis by mediating apoptosis, proliferation, and steroidogenesis in female mouse. Therefore Efna5 might be potential therapeutic target for female fertility disorders.
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Affiliation(s)
- Tesfaye Worku
- a Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction, Education Ministry of China, College of Animal Science and Technology , Huazhong Agricultural University , Wuhan 430070 , China.,b School of Veterinary Medicine , Wollega University , PO Box: 395, Nekemte , Ethiopia
| | - Kai Wang
- a Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction, Education Ministry of China, College of Animal Science and Technology , Huazhong Agricultural University , Wuhan 430070 , China
| | - Duncan Ayers
- c School of Health Sciences, Faculty of Biology, Medicine and Health , The University of Manchester M13 9PL , UK
| | - Di Wu
- a Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction, Education Ministry of China, College of Animal Science and Technology , Huazhong Agricultural University , Wuhan 430070 , China
| | - Zia Ur Rehman
- a Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction, Education Ministry of China, College of Animal Science and Technology , Huazhong Agricultural University , Wuhan 430070 , China
| | - Hao Zhou
- a Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction, Education Ministry of China, College of Animal Science and Technology , Huazhong Agricultural University , Wuhan 430070 , China
| | - Liguo Yang
- a Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction, Education Ministry of China, College of Animal Science and Technology , Huazhong Agricultural University , Wuhan 430070 , China
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Kou CTJ, Kandpal RP. Differential Expression Patterns of Eph Receptors and Ephrin Ligands in Human Cancers. BIOMED RESEARCH INTERNATIONAL 2018; 2018:7390104. [PMID: 29682554 PMCID: PMC5851329 DOI: 10.1155/2018/7390104] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/29/2017] [Revised: 01/11/2018] [Accepted: 01/22/2018] [Indexed: 12/20/2022]
Abstract
Eph receptors constitute the largest family of receptor tyrosine kinases, which are activated by ephrin ligands that either are anchored to the membrane or contain a transmembrane domain. These molecules play important roles in the development of multicellular organisms, and the physiological functions of these receptor-ligand pairs have been extensively documented in axon guidance, neuronal development, vascular patterning, and inflammation during tissue injury. The recognition that aberrant regulation and expression of these molecules lead to alterations in proliferative, migratory, and invasive potential of a variety of human cancers has made them potential targets for cancer therapeutics. We present here the involvement of Eph receptors and ephrin ligands in lung carcinoma, breast carcinoma, prostate carcinoma, colorectal carcinoma, glioblastoma, and medulloblastoma. The aberrations in their abundances are described in the context of multiple signaling pathways, and differential expression is suggested as the mechanism underlying tumorigenesis.
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Affiliation(s)
- Chung-Ting Jimmy Kou
- Department of Basic Medical Sciences, Western University of Health Sciences, Pomona, CA 91766, USA
| | - Raj P. Kandpal
- Department of Basic Medical Sciences, Western University of Health Sciences, Pomona, CA 91766, USA
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Ferrer VP, Moura Neto V, Mentlein R. Glioma infiltration and extracellular matrix: key players and modulators. Glia 2018; 66:1542-1565. [DOI: 10.1002/glia.23309] [Citation(s) in RCA: 102] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2017] [Revised: 01/18/2018] [Accepted: 01/29/2018] [Indexed: 12/14/2022]
Affiliation(s)
| | | | - Rolf Mentlein
- Department of Anatomy; University of Kiel; Kiel Germany
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Netrin-1 suppresses the MEK/ERK pathway and ITGB4 in pancreatic cancer. Oncotarget 2017; 7:24719-33. [PMID: 27034160 PMCID: PMC5029736 DOI: 10.18632/oncotarget.8348] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2015] [Accepted: 02/05/2016] [Indexed: 12/21/2022] Open
Abstract
The axon guidance factor netrin-1 promotes tumorigenesis in multiple types of cancers, particularly at their advanced stages. Here, we investigate whether netrin-1 is involved in the in vivo growth of pancreatic adenocarcinoma. We show that netrin-1 is significantly under-expressed in stage-I/II pancreatic ductal adenocarcinoma (PDAC). Netrin-1 over-expression effectively arrests the growth of xenografted PDAC cells without decreasing cell proliferation or increasing apoptosis in two-dimensional cultures in vitro. Integrin-beta4 (ITGB4) expression is significantly reduced, and ITGB4-knockdown mimics the tumor-suppressive effect of netrin-1, implying that ITGB4 is a main target of netrin-1 in constraining PDAC. We further show that netrin-1 signals to UNC5B/FAK to stimulate nitric oxide production, which promotes PP2A-mediated inhibition of the MEK/ERK pathway and decreases phosphorylated-c-Jun recruitment to the ITGB4 promoter. Our findings suggest that netrin-1 can suppress the growth of PDAC and provide a mechanistic insight into this suppression.
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Locke C, Machida K, Tucker CL, Wu Y, Yu J. Optogenetic activation of EphB2 receptor in dendrites induced actin polymerization by activating Arg kinase. Biol Open 2017; 6:1820-1830. [PMID: 29158322 PMCID: PMC5769660 DOI: 10.1242/bio.029900] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Erythropoietin-producing hepatocellular (Eph) receptors regulate a wide array of developmental processes by responding to cell-cell contacts. EphB2 is well-expressed in the brain and known to be important for dendritic spine development, as well as for the maintenance of the synapses, although the mechanisms of these functions have not been fully understood. Here we studied EphB2's functions in hippocampal neurons with an optogenetic approach, which allowed us to specify spatial regions of signal activation and monitor in real-time the consequences of signal activation. We designed and constructed OptoEphB2, a genetically encoded photoactivatable EphB2. Photoactivation of OptoEphB2 in fibroblast cells induced receptor phosphorylation and resulted in cell rounding ------- a well-known cellular response to EphB2 activation. In contrast, local activation of OptoEphb2 in dendrites of hippocampal neurons induces rapid actin polymerization, resulting dynamic dendritic filopodial growth. Inhibition of Rac1 and CDC42 did not abolish OptoEphB2-induced actin polymerization. Instead, we identified Abelson tyrosine-protein kinase 2 (Abl2/Arg) as a necessary effector in OptoEphB2-induced filopodia growth in dendrites. These findings provided new mechanistic insight into EphB2's role in neural development and demonstrated the advantage of OptoEphB as a new tool for studying EphB signaling.
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Affiliation(s)
- Clifford Locke
- Richard D. Berlin Center for Cell Analysis and Modeling, University of Connecticut Health Center, Farmington, CT 06030, USA
| | - Kazuya Machida
- Richard D. Berlin Center for Cell Analysis and Modeling, University of Connecticut Health Center, Farmington, CT 06030, USA
| | | | - Yi Wu
- Richard D. Berlin Center for Cell Analysis and Modeling, University of Connecticut Health Center, Farmington, CT 06030, USA
| | - Ji Yu
- Richard D. Berlin Center for Cell Analysis and Modeling, University of Connecticut Health Center, Farmington, CT 06030, USA
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Graves PR, Din SU, Ashamalla M, Ashamalla H, Gilbert TSK, Graves LM. Ionizing radiation induces EphA2 S897 phosphorylation in a MEK/ERK/RSK-dependent manner. Int J Radiat Biol 2017; 93:929-936. [PMID: 28705041 DOI: 10.1080/09553002.2017.1355580] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
PURPOSE The EphA2 tyrosine kinase is frequently overexpressed in human tumors that are also treated with radiation. However, few studies have examined the effect of radiation on the EphA2 receptor itself. The purpose of this project was to investigate the impact of radiation on EphA2 to better understand mechanisms of radioresistance. MATERIALS AND METHODS Cell lines were exposed to X-rays and assayed for changes in EphA2 protein levels and phosphorylation over time by Western blotting. HEK293 cells stably expressing wild-type EphA2 or the S897A mutant were analyzed for cell survival from X-rays. RESULTS Treatment of different cancer cell lines with 2 Gy of X-rays induced the phosphorylation of EphA2 on S897 but no changes were found in EphA2 total levels or its tyrosine phosphorylation. Radiation-induced S897 phosphorylation was unaffected by an AKT inhibitor but blocked by a MEK or RSK inhibitor. HEK293 cells expressing the EphA2 S897A mutant had a nearly 2-fold lower level of cell survival from X-rays than cells expressing wild-type EphA2. CONCLUSIONS These findings show that radiation induces S897 EphA2 phosphorylation, an event associated with increased cell survival. Therefore, targeting pathways that mediate EphA2 S897 phosphorylation may be a beneficial strategy to reduce radioresistance.
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Affiliation(s)
- Paul R Graves
- a Department of Radiation Oncology , New York-Presbyterian Brooklyn Methodist Hospital , Brooklyn , NY , USA
| | - Shaun U Din
- a Department of Radiation Oncology , New York-Presbyterian Brooklyn Methodist Hospital , Brooklyn , NY , USA
| | - Mark Ashamalla
- a Department of Radiation Oncology , New York-Presbyterian Brooklyn Methodist Hospital , Brooklyn , NY , USA
| | - Hani Ashamalla
- a Department of Radiation Oncology , New York-Presbyterian Brooklyn Methodist Hospital , Brooklyn , NY , USA
| | - Thomas S K Gilbert
- b Department of Pharmacology , University of North Carolina , Chapel Hill , NC , USA
| | - Lee M Graves
- b Department of Pharmacology , University of North Carolina , Chapel Hill , NC , USA
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Kang M, Jeong W, Bae H, Lim W, Bazer FW, Song G. Bifunctional role of ephrin A1-Eph system in stimulating cell proliferation and protecting cells from cell death through the attenuation of ER stress and inflammatory responses in bovine mammary epithelial cells. J Cell Physiol 2017; 233:2560-2571. [PMID: 28777434 DOI: 10.1002/jcp.26131] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2017] [Accepted: 08/03/2017] [Indexed: 01/09/2023]
Abstract
Structural and functional development of the mammary gland is constant in the mammary gland life cycle. Eph receptors and their ligands, ephrins, control events through cell-to-cell interactions during embryonic development, and adult tissue homeostasis; however, little information on participation of ephrin A1, a representative ligand of the Eph receptor, in the development and function of normal mammary glands is known. In this study, we demonstrated functional effects of the ephrin A1-Eph system and mechanisms of its action on bovine mammary epithelial (MAC-T) cells. The in vitro cultured MAC-T cells expressed the ephrin A1 ligand and EphA1, A2, A4, A7, and A8 among the eight members of the Eph A family. Our results revealed that ephrin A1 induced MAC-T cell cycle progression and stimulated cell proliferation with abundant expression of nucleic PCNA and cyclin D1 proteins. Additionally, ephrin A1 induced activation of intracellular signaling molecules involved in PI3 K/AKT and MAPK signaling, and the proliferation-stimulating effect of ephrin A1 was mediated by activation of these pathways. Furthermore, ephrin A1 influenced expression and activation of various ER stress-related proteins and protected MAC-T cells from stress-induced cell death. Finally, ephrin A1 alleviated LPS-induced cell death through down-regulation of inflammatory cytokines. In conclusion, the results of this study suggest that the Eph A-ephrin A1 system is a positive factor in the increase and maintenance of epithelial cells in mammary glands of cows; the signaling system contributes to development, remodeling, and functionality of normal mammary glands and could overcome mastitis in cows and other mammals.
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Affiliation(s)
- Minkyung Kang
- Institute of Animal Molecular Biotechnology and Department of Biotechnology, College of Life Sciences and Biotechnology, Korea University, Seoul, Republic of Korea
| | - Wooyoung Jeong
- Department of Animal Resources Science, Dankook University, Cheonan, Republic of Korea
| | - Hyocheol Bae
- Institute of Animal Molecular Biotechnology and Department of Biotechnology, College of Life Sciences and Biotechnology, Korea University, Seoul, Republic of Korea
| | - Whasun Lim
- Department of Biomedical Sciences, Catholic Kwandong University, Gangneung, Republic of Korea
| | - Fuller W Bazer
- Center for Animal Biotechnology and Genomics and Department of Animal Science, Texas A&M University, College Station, Texas
| | - Gwonhwa Song
- Institute of Animal Molecular Biotechnology and Department of Biotechnology, College of Life Sciences and Biotechnology, Korea University, Seoul, Republic of Korea
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Functional non-coding polymorphism in an EPHA2 promoter PAX2 binding site modifies expression and alters the MAPK and AKT pathways. Sci Rep 2017; 7:9992. [PMID: 28855599 PMCID: PMC5577203 DOI: 10.1038/s41598-017-10117-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2017] [Accepted: 08/04/2017] [Indexed: 01/11/2023] Open
Abstract
To identify possible genetic variants influencing expression of EPHA2 (Ephrin-receptor Type-A2), a tyrosine kinase receptor that has been shown to be important for lens development and to contribute to both congenital and age related cataract when mutated, the extended promoter region of EPHA2 was screened for variants. SNP rs6603883 lies in a PAX2 binding site in the EPHA2 promoter region. The C (minor) allele decreased EPHA2 transcriptional activity relative to the T allele by reducing the binding affinity of PAX2. Knockdown of PAX2 in human lens epithelial (HLE) cells decreased endogenous expression of EPHA2. Whole RNA sequencing showed that extracellular matrix (ECM), MAPK-AKT signaling pathways and cytoskeleton related genes were dysregulated in EPHA2 knockdown HLE cells. Taken together, these results indicate a functional non-coding SNP in EPHA2 promoter affects PAX2 binding and reduces EPHA2 expression. They further suggest that decreasing EPHA2 levels alters MAPK, AKT signaling pathways and ECM and cytoskeletal genes in lens cells that could contribute to cataract. These results demonstrate a direct role for PAX2 in EPHA2 expression and help delineate the role of EPHA2 in development and homeostasis required for lens transparency.
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Abstract
Eph-ephrin bidirectional signaling is essential for eye lens transparency in humans and mice. Our previous studies in mouse lenses demonstrate that ephrin-A5 is mainly expressed in the anterior epithelium, where it is required for maintaining the anterior epithelial monolayer. In contrast, EphA2 is localized in equatorial epithelial and fiber cells where it is essential for equatorial epithelial and fiber cell organization and hexagonal cell shape. Immunostaining of lens epithelial and fiber cells reveals that EphA2 and ephrin-A5 are also co-expressed in anterior fiber cell tips, equatorial epithelial cells and newly formed lens fibers, although they are not precisely colocalized. Due to this complex expression pattern and the promiscuous interactions between Eph receptors and ephrin ligands, as well as their complex bidirectional signaling pathways, cataracts in ephrin-A5(-/-) or EphA2(-/-) lenses may arise from loss of function or abnormal signaling mechanisms. To test whether abnormal signaling mechanisms may play a role in cataractogenesis in ephrin-A5(-/-) or EphA2(-/-) lenses, we generated EphA2 and ephrin-A5 double knockout (DKO) mice. We compared the phenotypes of EphA2(-/-) and ephrin-A5(-/-) lenses to that of DKO lenses. DKO lenses displayed an additive lens phenotype that was not significantly different from the two single KO lens phenotypes. Similar to ephrin-A5(-/-) lenses, DKO lenses had abnormal anterior epithelial cells leading to a large mass of epithelial cells that invade into the underlying fiber cell layer, directly resulting in anterior cataracts in ephrin-A5(-/-) and DKO lenses. Yet, similar to EphA2(-/-) lenses, DKO lenses also had abnormal packing of equatorial epithelial cells with disorganized meridional rows, lack of a lens fulcrum and disrupted fiber cells. The DKO lens phenotype rules out abnormal signaling by EphA2 in ephrin-A5(-/-) lenses or by ephrin-A5 in EphA2(-/-) lenses as possible cataract mechanisms. Thus, these results indicate that EphA2 and ephrin-A5 do not form a lens receptor-ligand pair, and that EphA2 and ephrin-A5 have other binding partners in the lens to help align differentiating equatorial epithelial cells or maintain the anterior epithelium, respectively.
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Cuyàs E, Queralt B, Martin-Castillo B, Bosch-Barrera J, Menendez JA. EphA2 receptor activation with ephrin-A1 ligand restores cetuximab efficacy in NRAS-mutant colorectal cancer cells. Oncol Rep 2017; 38:263-270. [DOI: 10.3892/or.2017.5682] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2017] [Accepted: 05/08/2017] [Indexed: 12/22/2022] Open
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Chen C, Song Z, Zheng X, He Z, Liu B, Huang X, Kong D, Ding D, Tang BZ. AIEgen-based theranostic system: targeted imaging of cancer cells and adjuvant amplification of antitumor efficacy of paclitaxel. Chem Sci 2017; 8:2191-2198. [PMID: 28507673 PMCID: PMC5407270 DOI: 10.1039/c6sc03859j] [Citation(s) in RCA: 81] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2016] [Accepted: 12/01/2016] [Indexed: 01/31/2023] Open
Abstract
Photosensitizers are generally treated as key components for photodynamic therapy. In contrast, we herein report an aggregation-induced emission luminogen (AIEgen)-based photosensitizer (TPE-Py-FFGYSA) that can serve as a non-toxic adjuvant to amplify the antitumor efficacy of paclitaxel, a well-known anticancer drug, with a synergistic effect of "0 + 1 > 1". Besides the adjuvant function, TPE-Py-FFGYSA can selectively light up EphA2 protein clusters overexpressed in cancer cells in a fluorescence turn-on mode, by taking advantage of the specific YSA peptide (YSAYPDSVPMMS)-EphA2 protein interaction. The simple incorporation of FFG as a self-assembly-aided unit between AIEgen (TPE-Py) and YSA significantly enhances the fluorescent signal output of TPE-Py when imaging EphA2 clusters in live cancer cells. Cytotoxicity and western blot studies reveal that the reactive oxygen species (ROS) generated by TPE-Py-FFGYSA upon exposure to light do not kill cancer cells, but instead provide an intracellular oxidative environment to help paclitaxel have much better efficacy. This study thus not only extends the application scope of photosensitizers, but also offers a unique theranostic system with the combination of diagnostic imaging and adjuvant antitumor therapy.
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Affiliation(s)
- Chao Chen
- Key Laboratory of Bioactive Materials , Ministry of Education , State Key Laboratory of Medicinal Chemical Biology , College of Life Sciences , Nankai University , Tianjin 300071 , China .
| | - Zhegang Song
- Department of Chemistry , Hong Kong Branch of Chinese National Engineering Research Center for Tissue Restoration and Reconstruction , Division of Biomedical Engineering , The Hong Kong University of Science & Technology (HKUST) , Clear Water Bay, Kowloon , Hong Kong , China .
| | - Xiaoyan Zheng
- Department of Chemistry , Hong Kong Branch of Chinese National Engineering Research Center for Tissue Restoration and Reconstruction , Division of Biomedical Engineering , The Hong Kong University of Science & Technology (HKUST) , Clear Water Bay, Kowloon , Hong Kong , China .
| | - Zikai He
- Department of Chemistry , Hong Kong Branch of Chinese National Engineering Research Center for Tissue Restoration and Reconstruction , Division of Biomedical Engineering , The Hong Kong University of Science & Technology (HKUST) , Clear Water Bay, Kowloon , Hong Kong , China .
| | - Bin Liu
- Department of Chemical and Biomolecular Engineering , National University of Singapore , 4 Engineering Drive 4 , Singapore 117585 .
| | - Xuhui Huang
- Department of Chemistry , Hong Kong Branch of Chinese National Engineering Research Center for Tissue Restoration and Reconstruction , Division of Biomedical Engineering , The Hong Kong University of Science & Technology (HKUST) , Clear Water Bay, Kowloon , Hong Kong , China .
| | - Deling Kong
- Key Laboratory of Bioactive Materials , Ministry of Education , State Key Laboratory of Medicinal Chemical Biology , College of Life Sciences , Nankai University , Tianjin 300071 , China .
| | - Dan Ding
- Key Laboratory of Bioactive Materials , Ministry of Education , State Key Laboratory of Medicinal Chemical Biology , College of Life Sciences , Nankai University , Tianjin 300071 , China .
| | - Ben Zhong Tang
- Department of Chemistry , Hong Kong Branch of Chinese National Engineering Research Center for Tissue Restoration and Reconstruction , Division of Biomedical Engineering , The Hong Kong University of Science & Technology (HKUST) , Clear Water Bay, Kowloon , Hong Kong , China .
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Lim W, Bae H, Bazer FW, Song G. Functional Roles of Eph A-Ephrin A1 System in Endometrial Luminal Epithelial Cells During Early Pregnancy. J Cell Physiol 2016; 232:1527-1538. [DOI: 10.1002/jcp.25659] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2016] [Accepted: 10/20/2016] [Indexed: 11/05/2022]
Affiliation(s)
- Whasun Lim
- Institute of Animal Molecular Biotechnology and Department of Biotechnology; College of Life Sciences and Biotechnology; Korea University; Seoul Republic of Korea
| | - Hyocheol Bae
- Institute of Animal Molecular Biotechnology and Department of Biotechnology; College of Life Sciences and Biotechnology; Korea University; Seoul Republic of Korea
| | - Fuller W. Bazer
- Center for Animal Biotechnology and Genomics and Department of Animal Science; Texas A&M University; College Station Texas
| | - Gwonhwa Song
- Institute of Animal Molecular Biotechnology and Department of Biotechnology; College of Life Sciences and Biotechnology; Korea University; Seoul Republic of Korea
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Regulation of endothelial migration and proliferation by ephrin-A1. Cell Signal 2016; 29:84-95. [PMID: 27742560 DOI: 10.1016/j.cellsig.2016.10.003] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2016] [Revised: 10/09/2016] [Accepted: 10/10/2016] [Indexed: 11/21/2022]
Abstract
Endothelial migration and proliferation are fundamental processes in angiogenesis and wound healing of injured or inflamed vessels. The present study aimed to investigate the regulation of the Eph/ephrin-system during endothelial proliferation and the impact of the ligand ephrin-A1 on proliferation and migration of human umbilical venous (HUVEC) and arterial endothelial cells (HUAEC). Endothelial cells that underwent contact inhibition showed a massive induction of ephrin-A1. In contrast, an injury to a confluent endothelial layer, associated with induction of migration and proliferation, showed reduced ephrin-A1 levels. In addition, reducing ephrin-A1 expression by siRNA led to increased proliferation, whereas the overexpression of ephrin-A1 led to decreased proliferative activity. Due to the fact that wound healing is a combination of proliferation and migration, migration was investigated in detail. First, classical wound-healing assays showed increased wound closure in both ephrin-A1 silenced and overexpressing cells. Live-cell imaging enlightened the underlying differences. Silencing of ephrin-A1 led to a faster but more disorientated migration. In contrast, ephrin-A1 overexpression did not influence velocity of the cells, but the migration was more directed in comparison to the controls. Additional analysis of EphA2-silenced cells showed similar results in terms of proliferation and migration compared to ephrin-A1 silenced cells. Detailed analysis of EphA2 phosphorylation on ligand-dependent phospho-site (Y588) and autonomous activation site (S897) revealed a distinct phosphorylation pattern. Furthermore, the endothelial cells ceased to migrate when they came in contact with an ephrin-A1 coated surface. Using a baculoviral-mediated expression system, ephrin-A1 silencing and overexpression was shown to modulate the formation of focal adhesions. This implicates that ephrin-A1 is involved in changes of the actin cytoskeleton which explains the alterations in migratory actions, at least in part. In conclusion, ephrin-A1 expression is regulated by cellular density and is itself a critical determinant of endothelial proliferation. According to current knowledge, ephrin-A1 seems to be remarkably involved in elementary processes of endothelial migration like cellular polarization, migratory direction and speed. These data support the notion that ephrin-A1 plays a pivotal role in basal mechanisms of re-endothelialization.
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Takano H, Nakamura T, Tsuchikawa T, Kushibiki T, Hontani K, Inoko K, Takahashi M, Sato S, Abe H, Takeuchi S, Sato N, Hiraoka K, Nishihara H, Shichinohe T, Hirano S. Inhibition of Eph receptor A4 by 2,5-dimethylpyrrolyl benzoic acid suppresses human pancreatic cancer growing orthotopically in nude mice. Oncotarget 2016; 6:41063-76. [PMID: 26516928 PMCID: PMC4747390 DOI: 10.18632/oncotarget.5729] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2015] [Accepted: 09/20/2015] [Indexed: 12/20/2022] Open
Abstract
Ephrin receptor A4 (EphA4) is overexpressed in human pancreatic adenocarcinoma (PDAC) and activate cell growth. Recent studies have identified small molecules that block EphA4. In this study, we investigated the correlation between EphA4 expression and the prognosis of patients with PDAC. We also examined the cytostatic efficacy of 2,5-dimethylpyrrolyl benzoic acid (compound 1), a small molecule that blocks EphA4, in PDAC cells. Overall survival of patients with EphA4 positivity was significantly shorter than that of patients with EphA4 negativity (P = 0.029). In addition, multivariate analysis revealed that EphA4 expression was an independent prognostic factor in PDAC patients (P = 0.039). Compound 1 showed a cytostatic efficacy in PDAC cells expressing EphA4 in vitro and in vivo. Our study indicated that compound 1 suppressed both EphA4 and Akt phosphorylations, and induced apoptosis in PDAC cells expressing EphA4. In conclusion,compound 1 has a high potential as a therapeutic agent for patients with PDAC.
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Affiliation(s)
- Hironobu Takano
- Department of Gastroenterological Surgery II, Hokkaido University Graduate School of Medicine, Sapporo 060-8638, Japan
| | - Toru Nakamura
- Department of Gastroenterological Surgery II, Hokkaido University Graduate School of Medicine, Sapporo 060-8638, Japan
| | - Takahiro Tsuchikawa
- Department of Gastroenterological Surgery II, Hokkaido University Graduate School of Medicine, Sapporo 060-8638, Japan
| | - Toshihiro Kushibiki
- Department of Gastroenterological Surgery II, Hokkaido University Graduate School of Medicine, Sapporo 060-8638, Japan
| | - Kouji Hontani
- Department of Gastroenterological Surgery II, Hokkaido University Graduate School of Medicine, Sapporo 060-8638, Japan
| | - Kazuho Inoko
- Department of Gastroenterological Surgery II, Hokkaido University Graduate School of Medicine, Sapporo 060-8638, Japan
| | - Mizuna Takahashi
- Department of Gastroenterological Surgery II, Hokkaido University Graduate School of Medicine, Sapporo 060-8638, Japan
| | - Shoki Sato
- Department of Gastroenterological Surgery II, Hokkaido University Graduate School of Medicine, Sapporo 060-8638, Japan
| | - Hirotake Abe
- Department of Gastroenterological Surgery II, Hokkaido University Graduate School of Medicine, Sapporo 060-8638, Japan
| | - Shintaro Takeuchi
- Department of Gastroenterological Surgery II, Hokkaido University Graduate School of Medicine, Sapporo 060-8638, Japan
| | - Nagato Sato
- Department of Gastroenterological Surgery II, Hokkaido University Graduate School of Medicine, Sapporo 060-8638, Japan
| | - Kei Hiraoka
- Department of Gastroenterological Surgery II, Hokkaido University Graduate School of Medicine, Sapporo 060-8638, Japan
| | - Hiroshi Nishihara
- Department of Translational Pathology, Hokkaido University Graduate School of Medicine, Sapporo 060-8638, Japan
| | - Toshiaki Shichinohe
- Department of Gastroenterological Surgery II, Hokkaido University Graduate School of Medicine, Sapporo 060-8638, Japan
| | - Satoshi Hirano
- Department of Gastroenterological Surgery II, Hokkaido University Graduate School of Medicine, Sapporo 060-8638, Japan
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Bhatia S, Baig NA, Timofeeva O, Pasquale EB, Hirsch K, MacDonald TJ, Dritschilo A, Lee YC, Henkemeyer M, Rood B, Jung M, Wang XJ, Kool M, Rodriguez O, Albanese C, Karam SD. Knockdown of EphB1 receptor decreases medulloblastoma cell growth and migration and increases cellular radiosensitization. Oncotarget 2016; 6:8929-46. [PMID: 25879388 PMCID: PMC4496193 DOI: 10.18632/oncotarget.3369] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2014] [Accepted: 02/11/2015] [Indexed: 02/03/2023] Open
Abstract
The expression of members of the Eph family of receptor tyrosine kinases and their ephrin ligands is frequently dysregulated in medulloblastomas. We assessed the expression and functional role of EphB1 in medulloblastoma cell lines and engineered mouse models. mRNA and protein expression profiling showed expression of EphB1 receptor in the human medulloblastoma cell lines DAOY and UW228. EphB1 downregulation reduced cell growth and viability, decreased the expression of important cell cycle regulators, and increased the percentage of cells in G1 phase of the cell cycle. It also modulated the expression of proliferation, and cell survival markers. In addition, EphB1 knockdown in DAOY cells resulted in significant decrease in migration, which correlated with decreased β1-integrin expression and levels of phosphorylated Src. Furthermore, EphB1 knockdown enhanced cellular radiosensitization of medulloblastoma cells in culture and in a genetically engineered mouse medulloblastoma model. Using genetically engineered mouse models, we established that genetic loss of EphB1 resulted in a significant delay in tumor recurrence following irradiation compared to EphB1-expressing control tumors. Taken together, our findings establish that EphB1 plays a key role in medulloblastoma cell growth, viability, migration, and radiation sensitivity, making EphB1 a promising therapeutic target.
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Affiliation(s)
- Shilpa Bhatia
- Department of Radiation Oncology, University of Colorado Denver, Anschutz Medical Campus, Aurora, CO, USA
| | - Nimrah A Baig
- Department of Oncology, Lombardi Comprehensive Cancer Center, Georgetown University Medical Center, Washington, DC, USA
| | - Olga Timofeeva
- Department of Oncology, Lombardi Comprehensive Cancer Center, Georgetown University Medical Center, Washington, DC, USA
| | | | - Kellen Hirsch
- Department of Radiation Oncology, University of Colorado Denver, Anschutz Medical Campus, Aurora, CO, USA
| | - Tobey J MacDonald
- Department of Pediatrics, Emory University School of Medicine, Atlanta, GA, USA
| | - Anatoly Dritschilo
- Department of Oncology, Lombardi Comprehensive Cancer Center, Georgetown University Medical Center, Washington, DC, USA.,Georgetown University Hospital, Washington, DC, USA
| | - Yi Chien Lee
- Department of Oncology, Lombardi Comprehensive Cancer Center, Georgetown University Medical Center, Washington, DC, USA
| | - Mark Henkemeyer
- Department of Developmental Biology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Brian Rood
- Children's National Medical Center, Washington DC, USA
| | - Mira Jung
- Department of Oncology, Lombardi Comprehensive Cancer Center, Georgetown University Medical Center, Washington, DC, USA
| | - Xiao-Jing Wang
- Department of Pathology, University of Colorado Denver, Anschutz Medical Campus, Aurora, CO, USA
| | - Marcel Kool
- Division of Pediatric Neurooncology, German Cancer Research Center DKFZ, Heidelberg, Germany
| | - Olga Rodriguez
- Department of Oncology, Lombardi Comprehensive Cancer Center, Georgetown University Medical Center, Washington, DC, USA
| | - Chris Albanese
- Department of Oncology, Lombardi Comprehensive Cancer Center, Georgetown University Medical Center, Washington, DC, USA.,Department of Pathology, Georgetown University School of Medicine, Washington, DC, USA
| | - Sana D Karam
- Department of Radiation Oncology, University of Colorado Denver, Anschutz Medical Campus, Aurora, CO, USA.,Department of Oncology, Lombardi Comprehensive Cancer Center, Georgetown University Medical Center, Washington, DC, USA
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Wijeratne DT, Rodger J, Wood FM, Fear MW. The role of Eph receptors and Ephrins in the skin. Int J Dermatol 2015; 55:3-10. [PMID: 26498559 DOI: 10.1111/ijd.12968] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/08/2014] [Revised: 11/21/2014] [Accepted: 12/31/2014] [Indexed: 12/01/2022]
Abstract
Eph receptors and Ephrin ligands are widely expressed in the skin. Various studies have been carried out to identify the effects of these molecules on many aspects of skin development. Here we summarize the literature that has identified roles for Eph receptors and Ephrins in the skin, focusing mainly on the epidermis, hair follicles, and cutaneous innervation. This review may help direct and focus further investigations into the role of Eph receptors and Ephrins in the development, maintenance, and repair processes in cutaneous biology.
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Affiliation(s)
- Dulharie T Wijeratne
- Burn Injury Research Unit, School of Surgery, University of Western Australia, Perth, WA, Australia
| | - Jennifer Rodger
- Experimental and Regenerative Neurosciences, School of Animal Biology, University of Western Australia, Perth, WA, Australia
| | - Fiona M Wood
- Burn Injury Research Unit, School of Surgery, University of Western Australia, Perth, WA, Australia.,The Fiona Wood Foundation, Perth, WA, Australia
| | - Mark W Fear
- Burn Injury Research Unit, School of Surgery, University of Western Australia, Perth, WA, Australia.,The Fiona Wood Foundation, Perth, WA, Australia
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Terriente J, Pujades C. Cell segregation in the vertebrate hindbrain: a matter of boundaries. Cell Mol Life Sci 2015; 72:3721-30. [PMID: 26089248 PMCID: PMC11113478 DOI: 10.1007/s00018-015-1953-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2015] [Revised: 05/06/2015] [Accepted: 06/08/2015] [Indexed: 02/07/2023]
Abstract
Segregating cells into compartments during embryonic development is essential for growth and pattern formation. In the developing hindbrain, boundaries separate molecularly, physically and neuroanatomically distinct segments called rhombomeres. After rhombomeric cells have acquired their identity, interhombomeric boundaries restrict cell intermingling between adjacent rhombomeres and act as signaling centers to pattern the surrounding tissue. Several works have stressed the relevance of Eph/ephrin signaling in rhombomeric cell sorting. Recent data have unveiled the role of this pathway in the assembly of actomyosin cables as an important mechanism for keeping cells from different rhombomeres segregated. In this Review, we will provide a short summary of recent evidences gathered in different systems suggesting that physical actomyosin barriers can be a general mechanism for tissue separation. We will discuss current evidences supporting a model where cell-cell signaling pathways, such as Eph/ephrin, govern compartmental cell sorting through modulation of the actomyosin cytoskeleton and cell adhesive properties to prevent cell intermingling.
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Affiliation(s)
- Javier Terriente
- Department of Experimental and Health Sciences, Universitat Pompeu Fabra, PRBB, Dr Aiguader 88, 08003, Barcelona, Spain.
| | - Cristina Pujades
- Department of Experimental and Health Sciences, Universitat Pompeu Fabra, PRBB, Dr Aiguader 88, 08003, Barcelona, Spain.
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Tegge AN, Sharp N, Murali TM. Xtalk: a path-based approach for identifying crosstalk between signaling pathways. Bioinformatics 2015; 32:242-51. [PMID: 26400040 DOI: 10.1093/bioinformatics/btv549] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2014] [Accepted: 09/04/2015] [Indexed: 12/26/2022] Open
Abstract
MOTIVATION Cells communicate with their environment via signal transduction pathways. On occasion, the activation of one pathway can produce an effect downstream of another pathway, a phenomenon known as crosstalk. Existing computational methods to discover such pathway pairs rely on simple overlap statistics. RESULTS We present Xtalk, a path-based approach for identifying pairs of pathways that may crosstalk. Xtalk computes the statistical significance of the average length of multiple short paths that connect receptors in one pathway to the transcription factors in another. By design, Xtalk reports the precise interactions and mechanisms that support the identified crosstalk. We applied Xtalk to signaling pathways in the KEGG and NCI-PID databases. We manually curated a gold standard set of 132 crosstalking pathway pairs and a set of 140 pairs that did not crosstalk, for which Xtalk achieved an area under the receiver operator characteristic curve of 0.65, a 12% improvement over the closest competing approach. The area under the receiver operator characteristic curve varied with the pathway, suggesting that crosstalk should be evaluated on a pathway-by-pathway level. We also analyzed an extended set of 658 pathway pairs in KEGG and to a set of more than 7000 pathway pairs in NCI-PID. For the top-ranking pairs, we found substantial support in the literature (81% for KEGG and 78% for NCI-PID). We provide examples of networks computed by Xtalk that accurately recovered known mechanisms of crosstalk. AVAILABILITY AND IMPLEMENTATION The XTALK software is available at http://bioinformatics.cs.vt.edu/~murali/software. Crosstalk networks are available at http://graphspace.org/graphs?tags=2015-bioinformatics-xtalk. CONTACT ategge@vt.edu, murali@cs.vt.edu SUPPLEMENTARY INFORMATION Supplementary data are available at Bioinformatics online.
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Affiliation(s)
- Allison N Tegge
- Department of Computer Science, Department of Statistics and
| | | | - T M Murali
- Department of Computer Science, ICTAS Center for Systems Biology of Engineered Tissues, Virginia Tech, Blacksburg, VA 24061, USA
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Ubiquitination switches EphA2 vesicular traffic from a continuous safeguard to a finite signalling mode. Nat Commun 2015; 6:8047. [PMID: 26292967 PMCID: PMC4560775 DOI: 10.1038/ncomms9047] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2015] [Accepted: 07/11/2015] [Indexed: 01/15/2023] Open
Abstract
Autocatalytic phosphorylation of receptor tyrosine kinases (RTKs) enables diverse, context-dependent responses to extracellular signals but comes at the price of autonomous, ligand-independent activation. Using a conformational biosensor that reports on the kinase activity of the cell guidance ephrin receptor type-A (EphA2) in living cells, we observe that autonomous EphA2 activation is suppressed by vesicular recycling and dephosphorylation by protein tyrosine phosphatases 1B (PTP1B) near the pericentriolar recycling endosome. This spatial segregation of catalytically superior PTPs from RTKs at the plasma membrane is essential to preserve ligand responsiveness. Ligand-induced clustering, on the other hand, promotes phosphorylation of a c-Cbl docking site and ubiquitination of the receptor, thereby redirecting it to the late endosome/lysosome. We show that this switch from cyclic to unidirectional receptor trafficking converts a continuous suppressive safeguard mechanism into a transient ligand-responsive signalling mode.
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Abstract
There is increasing evidence that in addition to having major roles in morphogenesis, in some tissues Eph receptor and ephrin signaling regulates the differentiation of cells. In one mode of deployment, cell contact dependent Eph-ephrin activation induces a distinct fate of cells at the interface of their expression domains, for example in early ascidian embryos and in the vertebrate hindbrain. In another mode, overlapping Eph receptor and ephrin expression underlies activation within a cell population, which promotes or inhibits cell differentiation in bone remodelling, neural progenitors and keratinocytes. Eph-ephrin activation also contributes to formation of the appropriate number of progenitor cells by increasing or decreasing cell proliferation. These multiple roles of Eph receptor and ephrin signaling may enable a coupling between morphogenesis and the differentiation and proliferation of cells.
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Key Words
- Eph receptor
- Eph receptor, Erythropoietin-producing hepatocellular carcinoma cell receptor
- FGF, Fibroblast growth factor
- IGF-1, Insulin-like growth factor-1
- JNK, c-Jun N-terminal kinase
- MAPK, Mitogen activated protein kinase
- NFAT, Nuclear factor of activated T-cells
- RGS3, Regulator of G-protein signaling 3
- STAT3, Signal transducer and activator of transcription 3
- TAZ, Tafazzin
- TCR, T cell receptor
- TEC, Thymic epithelial cell
- TGF, Transforming growth factor
- ZHX2, Zinc fingers and homeoboxes 2
- ascidian development
- bone
- cell proliferation
- differentiation
- ephrin
- ephrin, Eph receptor interacting protein
- hindbrain
- keratinocytes
- neural progenitors
- p120GAP, GTPase activating protein
- thymocytes
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Affiliation(s)
- David G Wilkinson
- a Division of Developmental Neurobiology; MRC National Institute for Medical Research ; London , UK
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Yuan B, Yu WY, Dai LS, Gao Y, Ding Y, Yu XF, Chen J, Zhang JB. Expression of microRNA‑26b and identification of its target gene EphA2 in pituitary tissues in Yanbian cattle. Mol Med Rep 2015; 12:5753-61. [PMID: 26252447 PMCID: PMC4581756 DOI: 10.3892/mmr.2015.4192] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2014] [Accepted: 04/22/2015] [Indexed: 01/11/2023] Open
Abstract
microRNAs (miRNAs/miRs) are a class of single-stranded non-coding RNA molecules of 19–24 nucleotides (nt) in length. They are widely expressed in animals, plants, bacteria and viruses. Via specific mRNA complementary pairing of target genes, miRNAs are able to regulate the expression of mRNA levels or inhibit protein translation following transcription. miRNA expression has a time- and space specificity, and it is involved in cell proliferation and differentiation, apoptosis, development, tumor metastasis occurrence and other biological processes. miR-26b is an miRNA of 22 nt and is important in the regulation of cellular processes. With the advancement of molecular biology techniques in recent years, there have been extensive investigations into miR-26b. Numerous studies have observed that miR-26b is involved in early embryonic development, cell proliferation regulation, pituitary hormone secretion and other physiological activities. miRNAs are associated with the function of propagation. The present study used reverse transcription quantitative polymerase chain reaction to detect the relative expression levels of miR-26b in the pituitary tissue of Yanbian cattle at different developmental stages. The 2−ΔΔCt method was used to calculate the relative gene expression levels. The miRNA target gene database TargetScan and RNA22 were used for prediction of the miR-26b target gene and selective recognition was also performed. The results demonstrated that miR-26b is expressed in the pituitary tissues of Yanbian cattle at 6 and 24 months of age. The relative expression levels of miR-26b in the pituitary tissues of 24-month-old Yanbian cattle were 2.41 times that of those in the six-month-old Yanbian cattle, demonstrating significant differences in the relative expression (P<0.01). The relative expression of the candidate target genes, EphA2 and miR-26b, exhibited the opposite expression pattern. The relative expression levels in the pituitary tissues of six-month-old Yanbian cattle were 3.34 times that of those in 24-month-old Yanbian cattle (P<0.01). There are miR-26b binding sites in the 3′-untranslated region (3′-UTR) of EphA2 in bovine, human, murine and other mammalian mRNAs, suggesting that the EphA2 gene may be a target gene of miR-26b. The results of a Luciferase reporter system assay revealed that miR-26b is able to suppress EphA2 expression at the transcription level. Following the site-directed mutagenesis of plasmid EphA2 3′-UTR pmirGLO-MUT- and miR-26b mimic-transfected HeLa cells, the dual-luciferase reporter gene assay revealed that there were three consecutive nucleotide mutations in the 3′-UTR, binding with the predicted seed region. This may have caused the miR-26b inhibition of luciferase activity to decrease from 60% in the wild-type to 26%, suggesting that miR-26b achieved its function via binding with the TACTTGAA sequence of the 3′-UTR in EphA2. In conclusion, the present study successfully assessed the expression pattern of miR-26b in the pituitary tissue of Yanbian cattle, and also confirmed that EphA2 was a target gene of miR-26b in Yanbian cattle in vitro. The present study provided the theoretical basis to further investigate the role of miR-26b in early embryonic development, pituitary hormone secretion and other reproductive functions.
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Affiliation(s)
- Bao Yuan
- Laboratory Animal Center, College of Animal Sciences, Jilin University, Changchun, Jilin 130062, P.R. China
| | - Wang-Yang Yu
- Laboratory Animal Center, College of Animal Sciences, Jilin University, Changchun, Jilin 130062, P.R. China
| | - Li-Sheng Dai
- Laboratory Animal Center, College of Animal Sciences, Jilin University, Changchun, Jilin 130062, P.R. China
| | - Yan Gao
- Laboratory Animal Center, College of Animal Sciences, Jilin University, Changchun, Jilin 130062, P.R. China
| | - Yu Ding
- Laboratory Animal Center, College of Animal Sciences, Jilin University, Changchun, Jilin 130062, P.R. China
| | - Xian-Feng Yu
- Laboratory Animal Center, College of Animal Sciences, Jilin University, Changchun, Jilin 130062, P.R. China
| | - Jian Chen
- Laboratory Animal Center, College of Animal Sciences, Jilin University, Changchun, Jilin 130062, P.R. China
| | - Jia-Bao Zhang
- Laboratory Animal Center, College of Animal Sciences, Jilin University, Changchun, Jilin 130062, P.R. China
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Koshikawa N, Hoshino D, Taniguchi H, Minegishi T, Tomari T, Nam SO, Aoki M, Sueta T, Nakagawa T, Miyamoto S, Nabeshima K, Weaver AM, Seiki M. Proteolysis of EphA2 Converts It from a Tumor Suppressor to an Oncoprotein. Cancer Res 2015; 75:3327-39. [PMID: 26130649 DOI: 10.1158/0008-5472.can-14-2798] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2014] [Accepted: 06/11/2015] [Indexed: 01/04/2023]
Abstract
Eph receptor tyrosine kinases are considered candidate therapeutic targets in cancer, but they can exert opposing effects on cell growth. In the presence of its ligands, Eph receptor EphA2 suppresses signaling by other growth factor receptors, including ErbB, whereas ligand-independent activation of EphA2 augments ErbB signaling. To deploy EphA2-targeting drugs effectively in tumors, the anti-oncogenic ligand-dependent activation state of EphA2 must be discriminated from its oncogenic ligand-independent state. Because the molecular basis for the latter is little understood, we investigated how the activation state of EphA2 can be switched in tumor tissue. We found that ligand-binding domain of EphA2 is cleaved frequently by the membrane metalloproteinase MT1-MMP, a powerful modulator of the pericellular environment in tumor cells. EphA2 immunostaining revealed a significant loss of the N-terminal portion of EphA2 in areas of tumor tissue that expressed MT1-MMP. Moreover, EphA2 phosphorylation patterns that signify ligand-independent activation were observed specifically in these areas of tumor tissue. Mechanistic experiments revealed that processing of EphA2 by MT1-MMP promoted ErbB signaling, anchorage-independent growth, and cell migration. Conversely, expression of a proteolysis-resistant mutant of EphA2 prevented tumorigenesis and metastasis of human tumor xenografts in mice. Overall, our results showed how the proteolytic state of EphA2 in tumors determines its effector function and influences its status as a candidate biomarker for targeted therapy.
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Affiliation(s)
- Naohiko Koshikawa
- Division of Cancer Cell Research, Institute of Medical Science, University of Tokyo, Tokyo, Japan
| | - Daisuke Hoshino
- Division of Cancer Cell Research, Institute of Medical Science, University of Tokyo, Tokyo, Japan. Department of Cancer Biology, Vanderbilt University School of Medicine, Nashville, Tennessee
| | - Hiroaki Taniguchi
- Division of Cancer Cell Research, Institute of Medical Science, University of Tokyo, Tokyo, Japan
| | - Tomoko Minegishi
- Division of Cancer Cell Research, Institute of Medical Science, University of Tokyo, Tokyo, Japan
| | - Taizo Tomari
- Division of Cancer Cell Research, Institute of Medical Science, University of Tokyo, Tokyo, Japan
| | - Sung-Ouk Nam
- Department of Obstetrics, Fukuoka University, Fukuoka, Japan
| | - Mikiko Aoki
- Department of Pathology, Fukuoka University, Fukuoka, Japan
| | - Takayuki Sueta
- Department of Otorhinolaryngology, Faculty of Medicine, Fukuoka University, Fukuoka, Japan
| | - Takashi Nakagawa
- Department of Otorhinolaryngology, Faculty of Medicine, Fukuoka University, Fukuoka, Japan
| | - Shingo Miyamoto
- Department of Obstetrics, Fukuoka University, Fukuoka, Japan
| | | | - Alissa M Weaver
- Department of Cancer Biology, Vanderbilt University School of Medicine, Nashville, Tennessee
| | - Motoharu Seiki
- Division of Cancer Cell Research, Institute of Medical Science, University of Tokyo, Tokyo, Japan. Integrated Center for Advanced Medical Technologies, Kochi Medical School, Kochi, Japan.
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Abstract
Alzheimer's disease (AD) represents the main form of dementia, and is a major public health problem. Despite intensive research efforts, current treatments have only marginal symptomatic benefits and there are no effective disease-modifying or preventive interventions. AD has a strong genetic component, so much research in AD has focused on identifying genetic causes and risk factors. This chapter will cover genetic discoveries in AD and their consequences in terms of improved knowledge regarding the disease and the identification of biomarkers and drug targets. First, we will discuss the study of the rare early-onset, autosomal dominant forms of AD that led to the discovery of mutations in three major genes, APP, PSEN1, and PSEN2. These discoveries have shaped our current understanding of the pathophysiology and natural history of AD as well as the development of therapeutic targets and the design of clinical trials. Then, we will explore linkage analysis and candidate gene approaches, which identified variants in Apolipoprotein E (APOE) as the major genetic risk factor for late-onset, "sporadic" forms of AD (LOAD), but failed to robustly identify other genetic risk factors, with the exception of variants in SORL1. The main focus of this chapter will be on recent genome-wide association studies that have successfully identified common genetic variations at over 20 loci associated with LOAD outside of the APOE locus. These loci are in or near-novel AD genes including BIN1, CR1, CLU, phosphatidylinositol-binding clathrin assembly protein (PICALM), CD33, EPHA1, MS4A4/MS4A6, ABCA7, CD2AP, SORL1, HLA-DRB5/DRB1, PTK2B, SLC24A4-RIN3, INPP5D, MEF2C, NME8, ZCWPW1, CELF1, FERMT2, CASS4, and TRIP4 and each has small effects on risk of AD (relative risks of 1.1-1.3). Finally, we will touch upon the ongoing effort to identify less frequent and rare variants through whole exome and whole genome sequencing. This effort has identified two novel genes, TREM2 and PLD3, and shown a role for APP in LOAD. The identification of these recently identified genes has implicated previously unsuspected biological pathways in the pathophysiology of AD.
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Affiliation(s)
- Vincent Chouraki
- Department of Neurology, Boston University School of Medicine, Boston, MA, USA; Framingham Heart Study, Framingham, MA, USA
| | - Sudha Seshadri
- Department of Neurology, Boston University School of Medicine, Boston, MA, USA; Framingham Heart Study, Framingham, MA, USA
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Miao H, Gale NW, Guo H, Qian J, Petty A, Kaspar J, Murphy AJ, Valenzuela DM, Yancopoulos G, Hambardzumyan D, Lathia JD, Rich JN, Lee J, Wang B. EphA2 promotes infiltrative invasion of glioma stem cells in vivo through cross-talk with Akt and regulates stem cell properties. Oncogene 2015; 34:558-67. [PMID: 24488013 PMCID: PMC4119862 DOI: 10.1038/onc.2013.590] [Citation(s) in RCA: 119] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2012] [Revised: 12/17/2013] [Accepted: 12/18/2013] [Indexed: 01/24/2023]
Abstract
Diffuse infiltrative invasion is a major cause for the dismal prognosis of glioblastoma multiforme (GBM), but the underlying mechanisms remain incompletely understood. Using human glioma stem cells (GSCs) that recapitulate the invasive propensity of primary GBM, we find that EphA2 critically regulates GBM invasion in vivo. EphA2 was expressed in all seven GSC lines examined, and overexpression of EphA2 enhanced intracranial invasion. The effects required Akt-mediated phosphorylation of EphA2 on serine 897. In vitro the Akt-EphA2 signaling axis is maintained in the absence of ephrin-A ligands and is disrupted upon ligand stimulation. To test whether ephrin-As in tumor microenvironment can regulate GSC invasion, the newly established Efna1;Efna3;Efna4 triple knockout mice (TKO) were used in an ex vivo brain slice invasion assay. We observed significantly increased GSC invasion through the brain slices of TKO mice relative to wild-type (WT) littermates. Mechanistically EphA2 knockdown suppressed stem cell properties of GSCs, causing diminished self-renewal, reduced stem marker expression and decreased tumorigenicity. In a subset of GSCs, the reduced stem cell properties were associated with lower Sox2 expression. Overexpression of EphA2 promoted stem cell properties in a kinase-independent manner and increased Sox2 expression. Disruption of Akt-EphA2 cross-talk attenuated stem cell marker expression and neurosphere formation while having minimal effects on tumorigenesis. Taken together, the results show that EphA2 endows invasiveness of GSCs in vivo in cooperation with Akt and regulates glioma stem cell properties.
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Affiliation(s)
- Hui Miao
- Rammelkamp Center for Research, MetroHealth Campus, and Department of Pharmacology and Oncology, Case Western Reserve University School of Medicine, 2500 MetroHealth Drive, Cleveland, Ohio 44109, USA
- VelociGene Division, Regeneron Pharmaceuticals, Inc., Tarrytown, NY 10591, USA
| | | | - Hong Guo
- Rammelkamp Center for Research, MetroHealth Campus, and Department of Pharmacology and Oncology, Case Western Reserve University School of Medicine, 2500 MetroHealth Drive, Cleveland, Ohio 44109, USA
- VelociGene Division, Regeneron Pharmaceuticals, Inc., Tarrytown, NY 10591, USA
| | - Juan Qian
- Rammelkamp Center for Research, MetroHealth Campus, and Department of Pharmacology and Oncology, Case Western Reserve University School of Medicine, 2500 MetroHealth Drive, Cleveland, Ohio 44109, USA
- VelociGene Division, Regeneron Pharmaceuticals, Inc., Tarrytown, NY 10591, USA
| | - Aaron Petty
- Rammelkamp Center for Research, MetroHealth Campus, and Department of Pharmacology and Oncology, Case Western Reserve University School of Medicine, 2500 MetroHealth Drive, Cleveland, Ohio 44109, USA
- VelociGene Division, Regeneron Pharmaceuticals, Inc., Tarrytown, NY 10591, USA
| | - James Kaspar
- Rammelkamp Center for Research, MetroHealth Campus, and Department of Pharmacology and Oncology, Case Western Reserve University School of Medicine, 2500 MetroHealth Drive, Cleveland, Ohio 44109, USA
- VelociGene Division, Regeneron Pharmaceuticals, Inc., Tarrytown, NY 10591, USA
| | | | | | | | - Dolores Hambardzumyan
- Department of Stem Cell Biology and Regenerative Medicine, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio, 9500 Euclid Ave, Cleveland, Ohio, 44195, USA
- Case Comprehensive Cancer Center, School of Medicine, Case Western Reserve University, 11100 Euclid Ave, Cleveland Ohio, 44106, USA
| | - Justin D. Lathia
- Department of Stem Cell Biology and Regenerative Medicine, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio, 9500 Euclid Ave, Cleveland, Ohio, 44195, USA
- Case Comprehensive Cancer Center, School of Medicine, Case Western Reserve University, 11100 Euclid Ave, Cleveland Ohio, 44106, USA
| | - Jeremy N. Rich
- Department of Stem Cell Biology and Regenerative Medicine, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio, 9500 Euclid Ave, Cleveland, Ohio, 44195, USA
- Case Comprehensive Cancer Center, School of Medicine, Case Western Reserve University, 11100 Euclid Ave, Cleveland Ohio, 44106, USA
| | - Jeongwu Lee
- Department of Stem Cell Biology and Regenerative Medicine, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio, 9500 Euclid Ave, Cleveland, Ohio, 44195, USA
- Case Comprehensive Cancer Center, School of Medicine, Case Western Reserve University, 11100 Euclid Ave, Cleveland Ohio, 44106, USA
| | - Bingcheng Wang
- Rammelkamp Center for Research, MetroHealth Campus, and Department of Pharmacology and Oncology, Case Western Reserve University School of Medicine, 2500 MetroHealth Drive, Cleveland, Ohio 44109, USA
- VelociGene Division, Regeneron Pharmaceuticals, Inc., Tarrytown, NY 10591, USA
- Case Comprehensive Cancer Center, School of Medicine, Case Western Reserve University, 11100 Euclid Ave, Cleveland Ohio, 44106, USA
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Sen S, Diercke K, Zingler S, Lux CJ, Erber R. Compression induces Ephrin-A2 in PDL fibroblasts via c-fos. J Dent Res 2015; 94:464-72. [PMID: 25604255 DOI: 10.1177/0022034514567197] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Ephrin-A2-EphA2 and ephrin-B2-EphB4 interactions have been implicated in the regulation of bone remodeling. We previously demonstrated a potential role for members of the Eph-ephrin family of receptor tyrosine kinases for bone remodeling during orthodontic tooth movement: compression-dependent upregulation of ephrin-A2 in fibroblasts of the periodontal ligament (PDL) attenuated osteogenesis in osteoblasts of the alveolar bone. However, factors affecting the regulation of ephrin-A2 expression upon the application of compressive forces remained unclear. Here, we report a mechano-dependent pathway of ephrin-A2 induction in PDL fibroblasts (PDLFs) involving extracellular signal-regulated kinases (ERK) 1/2 and c-fos. PDLF subjected to compressive forces (30.3 g/cm(2)) upregulated c-fos and ephrin-A2 mRNA and protein expression and displayed increased ERK1/2 phosphorylation. Inhibition of the MAP kinase kinase (MEK)/ERK1/2 pathway using the specific MEK inhibitor U0126 significantly reduced ephrin-A2 messenger RNA upregulation upon compression. Silencing of c-fos using a small interfering RNA approach led to a significant inhibition of ephrin-A2 induction upon the application of compressive forces. Interestingly, ephrin-A2 stimulation of PDLF induced c-fos expression and led also to the induction of ephrin-A2 expression. Using a reporter gene construct in murine 3T3 cells, we found that ephrin-A2 was able to stimulate serum response element (SRE)-dependent luciferase activity. As the regulation of c-fos is SRE dependent, ephrin-A2 might induce c-fos via SRE activation. Taken together, we provide evidence for an ERK1/2- and c-fos-dependent regulation of ephrin-A2 in compressed PDLF and suggest a novel pathway for ephrin-A2 induction emanating from ephrin-A2 itself. We showed previously that ephrin-A2 at compression sites might contribute to tooth movement by inhibiting osteogenic differentiation. The regulatory pathway of ephrin-A2 induction during tooth movement identified in this study might be accessible for pharmacological interventions.
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Affiliation(s)
- S Sen
- Department of Orthodontics and Dentofacial Orthopaedics, Dental School, University of Heidelberg, Heidelberg, Germany
| | - K Diercke
- Department of Orthodontics and Dentofacial Orthopaedics, Dental School, University of Heidelberg, Heidelberg, Germany
| | - S Zingler
- Department of Orthodontics and Dentofacial Orthopaedics, Dental School, University of Heidelberg, Heidelberg, Germany
| | - C J Lux
- Department of Orthodontics and Dentofacial Orthopaedics, Dental School, University of Heidelberg, Heidelberg, Germany
| | - R Erber
- Department of Orthodontics and Dentofacial Orthopaedics, Dental School, University of Heidelberg, Heidelberg, Germany
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Dewas C, Chen X, Honda T, Junttila I, Linton J, Udey MC, Porcella SF, Sturdevant DE, Feigenbaum L, Koo L, Williams J, Paul WE. TSLP expression: analysis with a ZsGreen TSLP reporter mouse. THE JOURNAL OF IMMUNOLOGY 2014; 194:1372-80. [PMID: 25539812 DOI: 10.4049/jimmunol.1400519] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Thymic stromal lymphopoietin (TSLP) is a type I cytokine that plays a central role in induction of allergic inflammatory responses. Its principal targets have been reported to be dendritic cells and/or CD4 T cells; epithelial cells are a principal source. We report in this study the development of a reporter mouse (TSLP-ZsG) in which a ZsGreen (ZsG)-encoding construct has been inserted by recombineering into a bacterial artificial chromosome immediately at the translation initiating ATG of TSLP. The expression of ZsG by mice transgenic for the recombinant BAC appears to be a faithful surrogate for TSLP expression, particularly in keratinocytes and medullary thymic epithelial cells. Limited ZsG and TSLP mRNA was observed in bone marrow-derived mast cells, basophils, and dendritic cells. Using the TSLP-ZsG reporter mouse, we show that TNF-α and IL-4/IL-13 are potent inducers of TSLP expression by keratinocytes and that local activation of Th2 and Th1 cells induces keratinocyte TSLP expression. We suggest that the capacity of TSLP to both induce Th2 differentiation and to be induced by activated Th2 cells raises the possibility that TSLP may be involved in a positive feedback loop to enhance allergic inflammatory conditions.
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Affiliation(s)
- Cedric Dewas
- Laboratory of Immunology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892
| | - Xi Chen
- Laboratory of Immunology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892
| | - Tetsuya Honda
- Laboratory of Systems Biology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892
| | - Ilkka Junttila
- Laboratory of Immunology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892
| | - Jay Linton
- Dermatology Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892
| | - Mark C Udey
- Dermatology Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892
| | - Stephen F Porcella
- Research Technology Branch, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892
| | - Daniel E Sturdevant
- Research Technology Branch, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892
| | - Lionel Feigenbaum
- Laboratory Animal Science Program, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892; and
| | - Lily Koo
- Research Technology Branch, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892
| | - Joy Williams
- Experimental Immunology Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892
| | - William E Paul
- Laboratory of Immunology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892;
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Al-Ejeh F, Offenhäuser C, Lim YC, Stringer BW, Day BW, Boyd AW. Eph family co-expression patterns define unique clusters predictive of cancer phenotype. Growth Factors 2014; 32:254-64. [PMID: 25410964 DOI: 10.3109/08977194.2014.984807] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The Eph genes are the largest sub-family of receptor tyrosine kinases; however, it is most likely the least understood and the arena for many conflicting reports. In this tribute to Prof. Martin Lackmann and Prof. Tony Pawson, we utilized The Cancer Genome Atlas resources to shed new light on the understanding of this family. We found that mutation and expression analysis define two clusters of co-expressed Eph family genes that relate to aggressive phenotypes across multiple cancer types. Analysis of signal transduction pathways using reverse-phase protein arrays revealed a network of interactions, which associates cluster-specific Eph genes with epithelial-mesenchymal transition, metabolism, DNA-damage repair and apoptosis. Our findings support the role of the Eph family in modulating cancer progression and reveal distinct patterns of Eph expression, which correlate with disease outcome. These observations provide further rationale for seeking cancer therapies, which target the Eph/ephrin system.
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Affiliation(s)
- Fares Al-Ejeh
- Brain Cancer Research Unit & Leukaemia Foundation Research Unit, QIMR Berghofer Medical Research Institute , Brisbane, Queensland , Australia
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82
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Micel LN, Tentler JJ, Tan AC, Selby HM, Brunkow KL, Robertson KM, Davis SL, Klauck PJ, Pitts TM, Gangolli E, Fabrey R, O'Connell SM, Vincent PW, Eckhardt SG. Antitumor activity of the MEK inhibitor TAK-733 against melanoma cell lines and patient-derived tumor explants. Mol Cancer Ther 2014; 14:317-25. [PMID: 25376610 DOI: 10.1158/1535-7163.mct-13-1012] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The goal of this study was to investigate the activity of the selective MEK1/2 inhibitor TAK-733 in both melanoma cell lines and patient-derived melanoma xenograft models. In vitro cell proliferation assays using the sulforhodamine B assay were conducted to determine TAK-733 potency and melanoma responsiveness. In vivo murine modeling with eleven patient-derived melanoma explants evaluated daily dosing of TAK-733 at 25 or 10 mg/kg. Immunoblotting was performed to evaluate on-target activity and downstream inhibition by TAK-733 in both in vitro and in vivo studies. TAK-733 demonstrated broad activity in most melanoma cell lines with relative resistance observed at IC50 > 0.1 μmol/L in vitro. TAK-733 also exhibited activity in 10 out of 11 patient-derived explants with tumor growth inhibition ranging from 0% to 100% (P < 0.001-0.03). Interestingly, BRAF(V600E) and NRAS mutational status did not correlate with responsiveness to TAK-733. Pharmacodynamically, pERK was suppressed in sensitive cell lines and tumor explants, confirming TAK-733-mediated inhibition of MEK1/2, although the demonstration of similar effects in the relatively resistant cell lines and tumor explants suggests that escape pathways are contributing to melanoma survival and proliferation. These data demonstrate that TAK-733 exhibits robust tumor growth inhibition and regression against human melanoma cell lines and patient-derived xenograft models, suggesting that further clinical development in melanoma is of scientific interest. Particularly interesting is the activity in BRAF wild-type models, where current approved therapy such as vemurafenib has been reported not to be active.
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Affiliation(s)
- Lindsey N Micel
- Division of Medical Oncology, University of Colorado, Anschutz Medical Campus, Aurora, Colorado. Division of Pediatric Hematology/Oncology, Children's Hospital Colorado, Anschutz Medical Campus, Aurora, Colorado
| | - John J Tentler
- Division of Medical Oncology, University of Colorado, Anschutz Medical Campus, Aurora, Colorado.
| | - Aik-Choon Tan
- Division of Medical Oncology, University of Colorado, Anschutz Medical Campus, Aurora, Colorado
| | - Heather M Selby
- Division of Medical Oncology, University of Colorado, Anschutz Medical Campus, Aurora, Colorado
| | - Kelsey L Brunkow
- Division of Medical Oncology, University of Colorado, Anschutz Medical Campus, Aurora, Colorado
| | - Kelli M Robertson
- Division of Medical Oncology, University of Colorado, Anschutz Medical Campus, Aurora, Colorado
| | - S Lindsey Davis
- Division of Medical Oncology, University of Colorado, Anschutz Medical Campus, Aurora, Colorado
| | - Peter J Klauck
- Division of Medical Oncology, University of Colorado, Anschutz Medical Campus, Aurora, Colorado
| | - Todd M Pitts
- Division of Medical Oncology, University of Colorado, Anschutz Medical Campus, Aurora, Colorado
| | - Esha Gangolli
- Takeda Pharmaceuticals, Inc., Cambridge, Massachusetts
| | - Robyn Fabrey
- Takeda Pharmaceuticals, Inc., San Diego, California
| | | | | | - S Gail Eckhardt
- Division of Medical Oncology, University of Colorado, Anschutz Medical Campus, Aurora, Colorado
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83
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Buricchi F, Giannoni E, Grimaldi G, Parri M, Raugei G, Ramponi G, Chiarugi P. Redox Regulation of Ephrin/Integrin Cross-Talk. Cell Adh Migr 2014. [DOI: 10.4161/cam.3911] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
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84
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Ottone C, Krusche B, Whitby A, Clements M, Quadrato G, Pitulescu ME, Adams RH, Parrinello S. Direct cell-cell contact with the vascular niche maintains quiescent neural stem cells. Nat Cell Biol 2014; 16:1045-56. [PMID: 25283993 PMCID: PMC4298702 DOI: 10.1038/ncb3045] [Citation(s) in RCA: 252] [Impact Index Per Article: 25.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2014] [Accepted: 08/28/2014] [Indexed: 02/07/2023]
Abstract
The vasculature is a prominent component of the subventricular zone neural stem cell niche. Although quiescent neural stem cells physically contact blood vessels at specialised endfeet, the significance of this interaction is not understood. In contrast, it is well established that vasculature-secreted soluble factors promote lineage progression of committed progenitors. Here we specifically investigated the role of cell-cell contact-dependent signalling in the vascular niche. Unexpectedly, we find that direct cell-cell interactions with endothelial cells enforces quiescence and promotes stem cell identity. Mechanistically, endothelial ephrinB2 and Jagged1 mediate these effects by suppressing cell-cycle entry downstream of mitogens and inducing stemness genes to jointly inhibit differentiation. In vivo, endothelial-specific ablation of either of the genes which encode these proteins, Efnb2 and Jag1 respectively, aberrantly activates quiescent stem cells, resulting in depletion. Thus, we identify the vasculature as a critical niche compartment for stem cell maintenance, furthering our understanding of how anchorage to the niche maintains stem cells within a pro-differentiative microenvironment.
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Affiliation(s)
- Cristina Ottone
- Cell Interactions and Cancer Group, MRC Clinical Sciences Centre, Imperial College London, Du Cane Road London W12 0NN, UK
| | - Benjamin Krusche
- Cell Interactions and Cancer Group, MRC Clinical Sciences Centre, Imperial College London, Du Cane Road London W12 0NN, UK
| | - Ariadne Whitby
- Cell Interactions and Cancer Group, MRC Clinical Sciences Centre, Imperial College London, Du Cane Road London W12 0NN, UK
| | - Melanie Clements
- Cell Interactions and Cancer Group, MRC Clinical Sciences Centre, Imperial College London, Du Cane Road London W12 0NN, UK
| | - Giorgia Quadrato
- Hertie Institute for Brain Research, University of Tuebingen, Tuebingen D-72076, Germany
| | - Mara E Pitulescu
- Department of Tissue Morphogenesis, Max Planck Institute for Molecular Biomedicine and Faculty of Medicine, University of Muenster, Muenster D-48149, Germany
| | - Ralf H Adams
- Department of Tissue Morphogenesis, Max Planck Institute for Molecular Biomedicine and Faculty of Medicine, University of Muenster, Muenster D-48149, Germany
| | - Simona Parrinello
- Cell Interactions and Cancer Group, MRC Clinical Sciences Centre, Imperial College London, Du Cane Road London W12 0NN, UK
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85
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Gucciardo E, Sugiyama N, Lehti K. Eph- and ephrin-dependent mechanisms in tumor and stem cell dynamics. Cell Mol Life Sci 2014; 71:3685-710. [PMID: 24794629 PMCID: PMC11113620 DOI: 10.1007/s00018-014-1633-0] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2013] [Revised: 03/31/2014] [Accepted: 04/17/2014] [Indexed: 01/17/2023]
Abstract
The erythropoietin-producing hepatocellular (Eph) receptors comprise the largest family of receptor tyrosine kinases (RTKs). Initially regarded as axon-guidance and tissue-patterning molecules, Eph receptors have now been attributed with various functions during development, tissue homeostasis, and disease pathogenesis. Their ligands, ephrins, are synthesized as membrane-associated molecules. At least two properties make this signaling system unique: (1) the signal can be simultaneously transduced in the receptor- and the ligand-expressing cell, (2) the signaling outcome through the same molecules can be opposite depending on cellular context. Moreover, shedding of Eph and ephrin ectodomains as well as ligand-dependent and -independent receptor crosstalk with other RTKs, proteases, and adhesion molecules broadens the repertoire of Eph/ephrin functions. These integrated pathways provide plasticity to cell-microenvironment communication in varying tissue contexts. The complex molecular networks and dynamic cellular outcomes connected to the Eph/ephrin signaling in tumor-host communication and stem cell niche are the main focus of this review.
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Affiliation(s)
- Erika Gucciardo
- Research Programs Unit, Genome-Scale Biology, Biomedicum Helsinki, University of Helsinki, P.O.B. 63, 00014 Helsinki, Finland
| | - Nami Sugiyama
- Research Programs Unit, Genome-Scale Biology, Biomedicum Helsinki, University of Helsinki, P.O.B. 63, 00014 Helsinki, Finland
- Department of Biosystems Science and Bioengineering, ETH Zurich, Mattenstrasse 26, 4058 Basel, Switzerland
| | - Kaisa Lehti
- Research Programs Unit, Genome-Scale Biology, Biomedicum Helsinki, University of Helsinki, P.O.B. 63, 00014 Helsinki, Finland
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86
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Nasreen N, Khodayari N, Sriram PS, Patel J, Mohammed KA. Tobacco smoke induces epithelial barrier dysfunction via receptor EphA2 signaling. Am J Physiol Cell Physiol 2014; 306:C1154-66. [PMID: 24717580 DOI: 10.1152/ajpcell.00415.2012] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Erythropoietin-producing human hepatocellular carcinoma (Eph) receptors are the largest family of receptor tyrosine kinases (RTKs) that mediate various cellular and developmental processes. The degrees of expression of these key molecules control the cell-cell interactions. Although the role of Eph receptors and their ligand Ephrins is well studied in developmental processes, their function in tobacco smoke (TS)-induced epithelial barrier dysfunction is unknown. We hypothesized that TS may induce permeability in bronchial airway epithelial cell (BAEpC) monolayer by modulating receptor EphA2 expression, actin cytoskeleton, adherens junction, and focal adhesion proteins. Here we report that in BAEpCs, acute TS exposure significantly upregulated EphA2 and EphrinA1 expression, disrupted the actin filaments, decreased E-cadherin expression, and increased protein permeability, whereas the focal adhesion protein paxillin was unaffected. Silencing the receptor EphA2 expression with silencing interference RNA (siRNA) significantly attenuated TS-induced hyperpermeability in BAEpCs. In addition, when BAEpC monolayer was transfected with EphA2-expressing plasmid and treated with recombinant EphrinA1, the transepithelial electrical resistance decreased significantly. Furthermore, TS downregulated E-cadherin expression and induced hyperpermeability across BAEpC monolayer in a Erk1/Erk2, p38, and JNK MAPK-dependent manner. TS induced hyperpermeability in BAEpC monolayer by targeting cell-cell adhesions, and interestingly cell-matrix adhesions were unaffected. The present data suggest that TS causes significant damage to the BAEpCs via induction of EphA2 and downregulation of E-cadherin. Induction of EphA2 in the BAEpCs exposed to TS may be an important signaling event in the pathogenesis of TS-induced epithelial injury.
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Affiliation(s)
- Najmunnisa Nasreen
- Division of Pulmonary, Critical Care and Sleep Medicine, Department of Medicine, University of Florida, Gainesville, Florida; and North Florida/South Georgia Veterans Health Care System, Malcom Randall Veterans Affairs Medical Center, University of Florida, Gainesville, Florida
| | - Nazli Khodayari
- Division of Pulmonary, Critical Care and Sleep Medicine, Department of Medicine, University of Florida, Gainesville, Florida; and North Florida/South Georgia Veterans Health Care System, Malcom Randall Veterans Affairs Medical Center, University of Florida, Gainesville, Florida
| | - Peruvemba S Sriram
- Division of Pulmonary, Critical Care and Sleep Medicine, Department of Medicine, University of Florida, Gainesville, Florida; and North Florida/South Georgia Veterans Health Care System, Malcom Randall Veterans Affairs Medical Center, University of Florida, Gainesville, Florida
| | - Jawaharlal Patel
- Division of Pulmonary, Critical Care and Sleep Medicine, Department of Medicine, University of Florida, Gainesville, Florida; and North Florida/South Georgia Veterans Health Care System, Malcom Randall Veterans Affairs Medical Center, University of Florida, Gainesville, Florida
| | - Kamal A Mohammed
- Division of Pulmonary, Critical Care and Sleep Medicine, Department of Medicine, University of Florida, Gainesville, Florida; and North Florida/South Georgia Veterans Health Care System, Malcom Randall Veterans Affairs Medical Center, University of Florida, Gainesville, Florida
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87
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Song W, Ma Y, Wang J, Brantley-Sieders D, Chen J. JNK signaling mediates EPHA2-dependent tumor cell proliferation, motility, and cancer stem cell-like properties in non-small cell lung cancer. Cancer Res 2014; 74:2444-54. [PMID: 24607842 DOI: 10.1158/0008-5472.can-13-2136] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Recent genome-wide analyses in human lung cancer revealed that EPHA2 receptor tyrosine kinase is overexpressed in non-small cell lung cancer (NSCLC), and high levels of EPHA2 correlate with poor clinical outcome. However, the mechanistic basis for EPHA2-mediated tumor promotion in lung cancer remains poorly understood. Here, we show that the JNK/c-JUN signaling mediates EPHA2-dependent tumor cell proliferation and motility. A screen of phospho-kinase arrays revealed a decrease in phospho-c-JUN levels in EPHA2 knockdown cells. Knockdown of EPHA2 inhibited p-JNK and p-c-JUN levels in approximately 50% of NSCLC lines tested. Treatment of parental cells with SP600125, a c-JUN-NH2-kinase (JNK) inhibitor, recapitulated defects in EPHA2-deficient tumor cells, whereas constitutively activated JNK mutants were sufficient to rescue phenotypes. Knockdown of EPHA2 also inhibited tumor formation and progression in xenograft animal models in vivo. Furthermore, we investigated the role of EPHA2 in cancer stem-like cells (CSC). RNA interference-mediated depletion of EPHA2 in multiple NSCLC lines decreased the ALDH(+) cancer stem-like population and tumor spheroid formation in suspension. Depletion of EPHA2 in sorted ALDH(+) populations markedly inhibited tumorigenicity in nude mice. Furthermore, analysis of a human lung cancer tissue microarray revealed a significant, positive association between EPHA2 and ALDH expression, indicating an important role for EPHA2 in human lung CSCs. Collectively, these studies revealed a critical role of JNK signaling in EPHA2-dependent lung cancer cell proliferation and motility and a role for EPHA2 in CSC function, providing evidence for EPHA2 as a potential therapeutic target in NSCLC. Cancer Res; 74(9); 2444-54. ©2014 AACR.
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Affiliation(s)
- Wenqiang Song
- Authors' Affiliations: Veterans Affairs Medical Center, Tennessee Valley Healthcare System; Division of Rheumatology and Immunology, Department of Medicine; Departments of Neurological Surgery, Cancer Biology, and Cell and Developmental Biology; and Vanderbilt-Ingram Cancer Center, Vanderbilt University School of Medicine, Nashville, Tennessee
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88
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Xi HQ, Wu XS, Wei B, Chen L. Eph receptors and ephrins as targets for cancer therapy. J Cell Mol Med 2014; 16:2894-909. [PMID: 22862837 PMCID: PMC4393718 DOI: 10.1111/j.1582-4934.2012.01612.x] [Citation(s) in RCA: 85] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2012] [Accepted: 07/13/2012] [Indexed: 12/15/2022] Open
Abstract
Eph receptor tyrosine kinases and their ephrin ligands are involved in various signalling pathways and mediate critical steps of a wide variety of physiological and pathological processes. Increasing experimental evidence demonstrates that both Eph receptor and ephrin ligands are overexpressed in a number of human tumours, and are associated with tumour growth, invasiveness and metastasis. In this regard, the Eph/ephrin system provides the foundation for potentially exciting new targets for anticancer therapies for Eph-expressing tumours. The purpose of this review is to outline current advances in the role of Eph receptors and ephrin ligands in cancer, and to discuss novel therapeutic approaches of anticancer therapies.
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Affiliation(s)
- Hong-Qing Xi
- Department of General Surgery, Chinese People's Liberation Army General Hospital, Beijing, China
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89
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Keane N, Freeman C, Swords R, Giles FJ. EPHA3 as a novel therapeutic target in the hematological malignancies. Expert Rev Hematol 2014; 5:325-40. [DOI: 10.1586/ehm.12.19] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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90
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91
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Yamada T, Yuasa M, Masaoka T, Taniyama T, Maehara H, Torigoe I, Yoshii T, Shinomiya K, Okawa A, Sotome S. After repeated division, bone marrow stromal cells express inhibitory factors with osteogenic capabilities, and EphA5 is a primary candidate. Bone 2013; 57:343-54. [PMID: 24029132 DOI: 10.1016/j.bone.2013.08.028] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/01/2013] [Revised: 08/23/2013] [Accepted: 08/29/2013] [Indexed: 01/01/2023]
Abstract
The differentiation capability of human bone marrow stromal cells (hBMSCs) is thought to deteriorate over multiple doubling processes. To clarify the deterioration mechanisms, the multilineage differentiation capabilities of short- and long-term passaged BMSCs were compared. Predictably, long-term passaged BMSCs showed reduced differentiation capacities compared to short-term passaged cells. Furthermore, a non-human primate heterotopic bone formation model demonstrated that long-term passaged BMSCs have bone formation capabilities but also exert inhibitory effects on bone formation. This finding indicated that long-term passaged BMSCs express higher levels of inhibitory factors than short-term passaged BMSCs do. Co-culture assays of short- and long-term passaged BMSCs suggested that the inhibitory signals required cell-cell contact and would therefore be expressed on the cell membrane. A microarray analysis of BMSCs identified ephrin type-A receptor 5 (EphA5) as an inhibitory factor candidate. Quantitative PCR revealed that among all members of the ephrin and Eph receptor families, only the expression of EphA5 was increased by BMSC proliferation. A gene knockdown analysis using siRNAs demonstrated that knockdown of EphA5 gene expression in long-term passaged BMSCs led to an increase in ALP mRNA expression. These results indicate that EphA5 may be a negative regulator of bone formation. A better understanding of the roles of the ephrin and Eph receptor families in hBMSCs may lead to alternative approaches for manipulating hBMSC fate. In addition, this avenue of discovery may provide new therapeutic targets and quality-control markers of the osteogenic differentiation capabilities of hBMSCs.
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Affiliation(s)
- Tsuyoshi Yamada
- Department of Orthopaedic and Spinal Surgery, Graduate School, Tokyo Medical and Dental University, Tokyo, Japan; Global Center of Excellence (GCOE) Program, International Research Center for Molecular Science in Tooth and Bone Diseases, Tokyo Medical and Dental University, Tokyo, Japan
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92
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Falivelli G, Lisabeth EM, de la Torre ER, Perez-Tenorio G, Tosato G, Salvucci O, Pasquale EB. Attenuation of eph receptor kinase activation in cancer cells by coexpressed ephrin ligands. PLoS One 2013; 8:e81445. [PMID: 24348920 PMCID: PMC3857839 DOI: 10.1371/journal.pone.0081445] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2013] [Accepted: 10/21/2013] [Indexed: 12/20/2022] Open
Abstract
The Eph receptor tyrosine kinases mediate juxtacrine signals by interacting “in trans” with ligands anchored to the surface of neighboring cells via a GPI-anchor (ephrin-As) or a transmembrane segment (ephrin-Bs), which leads to receptor clustering and increased kinase activity. Additionally, soluble forms of the ephrin-A ligands released from the cell surface by matrix metalloproteases can also activate EphA receptor signaling. Besides these trans interactions, recent studies have revealed that Eph receptors and ephrins coexpressed in neurons can also engage in lateral “cis” associations that attenuate receptor activation by ephrins in trans with critical functional consequences. Despite the importance of the Eph/ephrin system in tumorigenesis, Eph receptor-ephrin cis interactions have not been previously investigated in cancer cells. Here we show that in cancer cells, coexpressed ephrin-A3 can inhibit the ability of EphA2 and EphA3 to bind ephrins in trans and become activated, while ephrin-B2 can inhibit not only EphB4 but also EphA3. The cis inhibition of EphA3 by ephrin-B2 implies that in some cases ephrins that cannot activate a particular Eph receptor in trans can nevertheless inhibit its signaling ability through cis association. We also found that an EphA3 mutation identified in lung cancer enhances cis interaction with ephrin-A3. These results suggest a novel mechanism that may contribute to cancer pathogenesis by attenuating the tumor suppressing effects of Eph receptor signaling pathways activated by ephrins in trans.
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Affiliation(s)
- Giulia Falivelli
- Sanford-Burnham Medical Research Institute, San Diego, California, United States of America
- Department Pharmacology, University of Bologna, Bologna, Italy
| | - Erika Mathes Lisabeth
- Sanford-Burnham Medical Research Institute, San Diego, California, United States of America
| | | | - Gizeh Perez-Tenorio
- Sanford-Burnham Medical Research Institute, San Diego, California, United States of America
| | - Giovanna Tosato
- Laboratory of Cellular Oncology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Ombretta Salvucci
- Laboratory of Cellular Oncology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Elena B. Pasquale
- Sanford-Burnham Medical Research Institute, San Diego, California, United States of America
- Department of Pathology, University of California San Diego, San Diego, California, United States of America
- * E-mail:
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93
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Lee HY, Mohammed KA, Kaye F, Sharma P, Moudgil BM, Clapp WL, Nasreen N. Targeted delivery of let-7a microRNA encapsulated ephrin-A1 conjugated liposomal nanoparticles inhibit tumor growth in lung cancer. Int J Nanomedicine 2013; 8:4481-94. [PMID: 24293999 PMCID: PMC3839802 DOI: 10.2147/ijn.s41782] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
MicroRNAs (miRs) are small noncoding RNA sequences that negatively regulate the expression of target genes by posttranscriptional repression. miRs are dysregulated in various diseases, including cancer. let-7a miR, an antioncogenic miR, is downregulated in lung cancers. Our earlier studies demonstrated that let-7a miR inhibits tumor growth in malignant pleural mesothelioma (MPM) and could be a potential therapeutic against lung cancer. EphA2 (ephrin type-A receptor 2) tyrosine kinase is overexpressed in most cancer cells, including MPM and non-small-cell lung cancer (NSCLC) cells. Ephrin-A1, a specific ligand of the EphA2 receptor, inhibits cell proliferation and migration. In this study, to enhance the delivery of miR, the miRs were encapsulated in the DOTAP (N-[1-(2.3-dioleoyloxy)propyl]-N,N,N-trimethyl ammonium)/Cholesterol/DSPE (1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N-[cyanur(polyethylene glycol)-2000])-PEG (polyethylene glycol)-cyanur liposomal nanoparticles (LNP) and ephrin-A1 was conjugated on the surface of LNP to target receptor EphA2 on lung cancer cells. The LNP with an average diameter of 100 nm showed high stability, low cytotoxicity, and high loading efficiency of precursor let-7a miR and ephrin-A1. The ephrin-A1 conjugated LNP (ephrin-A1–LNP) and let-7a miR encapsulated LNP (miR–LNP) showed improved transfection efficiency against MPM and NSCLC. The effectiveness of targeted delivery of let-7a miR encapsulated ephrin-A1 conjugated LNP (miR–ephrin-A1–LNP) was determined on MPM and NSCLC tumor growth in vitro. miR–ephrin-A1–LNP significantly increased the delivery of let-7a miR in lung cancer cells when compared with free let-7a miR. In addition, the expression of target gene Ras was significantly repressed following miR–ephrin-A1–LNP treatment. Furthermore, the miR–ephrin-A1–LNP complex significantly inhibited MPM and NSCLC proliferation, migration, and tumor growth. Our results demonstrate that the engineered miR–ephrin-A1–LNP complex is an effective carrier for the targeted delivery of small RNA molecules to lung cancer cells. This could be a potential therapeutic approach against tumors overexpressing the EphA2 receptor.
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Affiliation(s)
- Hung-Yen Lee
- Division of Pulmonary, Critical Care and Sleep Medicine, Department of Medicine in the College of Medicine, Gainesville, FL, USA ; Biomaterials Center, Department of Materials Sciences and Engineering, Gainesville, FL, USA
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94
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Li RX, Chen ZH, Chen ZK. The role of EPH receptors in cancer-related epithelial-mesenchymal transition. CHINESE JOURNAL OF CANCER 2013; 33:231-40. [PMID: 24103789 PMCID: PMC4026543 DOI: 10.5732/cjc.013.10108] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Erythropoietin-producing hepatoma (EPH) receptors are considered the largest family of receptor tyrosine kinases and play key roles in physiological and pathologic processes in development and disease. EPH receptors are often overexpressed in human malignancies and are associated with poor prognosis. However, the functions of EPH receptors in epithelial-mesenchymal transition (EMT) remain largely unknown. This review depicts the relationship between EPH receptors and the EMT marker E-cadherin as well as the crosstalk between EPH receptors and the signaling pathways involved EMT. Further discussion is focused on the clinical significance of EPH receptors as candidates for targeting in cancer therapeutics. Finally, we summarize how targeted inhibition of both EPH receptors and EMT-related signaling pathways represents a novel strategy for cancer treatment.
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Affiliation(s)
- Rui-Xin Li
- Department of Gastrointestinal Surgery, Xiangya Hospital, Central South University, Changsha, Hunan 410008, P. R. China.
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95
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Ohta N, Satou Y. Multiple signaling pathways coordinate to induce a threshold response in a chordate embryo. PLoS Genet 2013; 9:e1003818. [PMID: 24098142 PMCID: PMC3789818 DOI: 10.1371/journal.pgen.1003818] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2013] [Accepted: 08/07/2013] [Indexed: 12/11/2022] Open
Abstract
In animal development, secreted signaling molecules evoke all-or-none threshold responses of target gene transcription to specify cell fates. In the chordate Ciona intestinalis, the neural markers Otx and Nodal are induced at early embryonic stages by Fgf9/16/20 signaling. Here we show that three additional signaling molecules act negatively to generate a sharp expression boundary for neural genes. EphrinA signaling antagonizes FGF signaling by inhibiting ERK phosphorylation more strongly in epidermal cells than in neural cells, which accentuates differences in the strength of ERK activation. However, even weakly activated ERK activates Otx and Nodal transcription occasionally, probably because of the inherently stochastic nature of signal transduction processes and binding of transcription factors to target sequences. This occasional and undesirable activation of neural genes by weak residual ERK activity is directly repressed by Smad transcription factors activated by Admp and Gdf1/3-like signaling, further sharpening the differential responses of cells to FGF signaling. Thus, these signaling pathways coordinate to evoke a threshold response that delineates a sharp expression boundary.
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Affiliation(s)
- Naoyuki Ohta
- Department of Zoology, Graduate School of Science, Kyoto University, Sakyo, Kyoto, Japan
| | - Yutaka Satou
- Department of Zoology, Graduate School of Science, Kyoto University, Sakyo, Kyoto, Japan
- * E-mail:
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Haupaix N, Stolfi A, Sirour C, Picco V, Levine M, Christiaen L, Yasuo H. p120RasGAP mediates ephrin/Eph-dependent attenuation of FGF/ERK signals during cell fate specification in ascidian embryos. Development 2013; 140:4347-52. [PMID: 24067356 DOI: 10.1242/dev.098756] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
ERK1/2 MAP kinase exhibits a highly dynamic activation pattern in developing embryos, which largely depends on fibroblast growth factor (FGF) signals. In ascidian embryos, FGF-dependent activation of ERK1/2 occurs differentially between sister cells during marginal zone and neural lineage patterning. Selective attenuation of FGF signals by localised ephrin/Eph signals accounts for this differential ERK activation, which controls the binary fate choice of each sibling cell pair. Here, we show that p120 Ras GTPase-activating protein (p120RasGAP) is a crucial mediator of these ephrin/Eph signals. First, inhibition of p120RasGAP has a similar effect to inhibition of ephrin/Eph function during marginal zone and neural patterning. Second, p120RasGAP acts epistatically to ephrin/Eph signals. Third, p120RasGAP physically associates with Eph3 in an ephrin-dependent manner. This study provides the first in vivo evidence that the functional association between Eph and RasGAP controls the spatial extent of FGF-activated ERK.
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Affiliation(s)
- Nicolas Haupaix
- Université Pierre et Marie Curie and Centre National de la Recherche Scientifique, Laboratoire de Biologie du Développement de Villefranche-sur-Mer, Observatoire Océanologique, 06230 Villefranche-sur-Mer, France
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97
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Lisabeth EM, Falivelli G, Pasquale EB. Eph receptor signaling and ephrins. Cold Spring Harb Perspect Biol 2013; 5:5/9/a009159. [PMID: 24003208 DOI: 10.1101/cshperspect.a009159] [Citation(s) in RCA: 281] [Impact Index Per Article: 25.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The Eph receptors are the largest of the RTK families. Like other RTKs, they transduce signals from the cell exterior to the interior through ligand-induced activation of their kinase domain. However, the Eph receptors also have distinctive features. Instead of binding soluble ligands, they generally mediate contact-dependent cell-cell communication by interacting with surface-associated ligands-the ephrins-on neighboring cells. Eph receptor-ephrin complexes emanate bidirectional signals that affect both receptor- and ephrin-expressing cells. Intriguingly, ephrins can also attenuate signaling by Eph receptors coexpressed in the same cell. Additionally, Eph receptors can modulate cell behavior independently of ephrin binding and kinase activity. The Eph/ephrin system regulates many developmental processes and adult tissue homeostasis. Its abnormal function has been implicated in various diseases, including cancer. Thus, Eph receptors represent promising therapeutic targets. However, more research is needed to better understand the many aspects of their complex biology that remain mysterious.
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Affiliation(s)
- Erika M Lisabeth
- Cancer Center, Sanford-Burnham Medical Research Institute, La Jolla, California 92037, USA
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98
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Prognostic significance of combinations of RNA-dependent protein kinase and EphA2 biomarkers for NSCLC. J Thorac Oncol 2013; 8:301-8. [PMID: 23370317 DOI: 10.1097/jto.0b013e318282def7] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
INTRODUCTION RNA-dependent protein kinase (PKR) is an independent prognostic variable in patients with non-small-cell lung cancer (NSCLC). In the current study, we investigated the correlation between PKR and 25 other biomarkers for NSCLC, identified the markers that could further improve the prognostic significance of PKR and elucidated the mechanisms of interaction between these markers and PKR. METHODS Tissue microarray samples obtained from 218 patients with lung cancer were stained with an anti-PKR antibody and antibodies against 25 biomarkers. Immunohistochemical expression was scored and used for Kaplan-Meier survival analysis. The interaction between PKR and EphA2 in NSCLC cell lines was examined. RESULTS We found that PKR was associated with EphA2 and that the prognostic information regarding NSCLC provided by the combination of PKR and EphA2 (P/E) was significantly more accurate than that provided by either marker alone. The 5-year overall survival rate in patients with PKR/EphA2 (20%) was significantly lower than that of patients with PKR/EphA2 (74%), patients with PKR/EphA2 (55%), and patients with PKR/EphA2 (55%) (p < 0.0001). We also found that the PKR:EphA2 (P/E) ratio was significantly associated with prognosis (p < 0.0001). Univariate and multivariate Cox analyses revealed that this P/E combination or ratio was an independent predictor of overall survival. In addition, induction of PKR expression reduced EphA2 protein expression levels in NSCLC cell lines. CONCLUSIONS PKR/EphA2 is a significant predictor of prognosis for NSCLC. PKR/EphA2 may be a promising approach to improving screening efficiency and predicting prognosis in patients with NSCLC.
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EphA2 promotes epithelial-mesenchymal transition through the Wnt/β-catenin pathway in gastric cancer cells. Oncogene 2013; 33:2737-47. [PMID: 23752181 DOI: 10.1038/onc.2013.238] [Citation(s) in RCA: 162] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2013] [Revised: 05/03/2013] [Accepted: 05/10/2013] [Indexed: 12/18/2022]
Abstract
This study aims to investigate the significance of erythropoietin-producing hepatocellular (Eph)A2 expression and the mechanism by which EphA2 is involved in the epithelial-mensenchymal transition (EMT) of gastric cancer cells. EphA2 expression levels were upregulated and positively correlated with metastasis and EMT markers in human gastric cancer specimens. Modulation of EphA2 expression levels had distinct effects on cell proliferation, cell cycle, migration, invasion and morphology in the gastric cancer cell lines SGC7901 and AGS in vitro and in vivo. Overexpression of EphA2 resulted in the upregulation of the EMT molecular markers N-cadherin and Snail, as well as the Wnt/β-catenin targets TCF4, Cyclin-D1 and c-Myc, while silencing EphA2 using short hairpin RNA had the opposite effect. Furthermore, inhibition of the Wnt/β-catenin pathway by XAV939 negated the effect of EphA2 overexpression, whereas activation of the Wnt/β-catenin pathway by LiCl impaired the effect of the EphA2 knockdown on EMT. These observations demonstrate that EphA2 upregulation is a common event in gastric cancer specimens that is closely correlated with cancer metastasis and that EphA2 promotes EMT of gastric cancer cells through activation of Wnt/β-catenin signaling.
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100
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Burch TC, Watson MT, Nyalwidhe JO. Variable metastatic potentials correlate with differential plectin and vimentin expression in syngeneic androgen independent prostate cancer cells. PLoS One 2013; 8:e65005. [PMID: 23717685 PMCID: PMC3661497 DOI: 10.1371/journal.pone.0065005] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2012] [Accepted: 04/24/2013] [Indexed: 12/30/2022] Open
Abstract
Prostate cancer is a clinically heterogeneous disease, ranging from indolent asymptomatic disease to very aggressive metastatic and life threatening forms of the disease. Distant metastasis represents the major lethal cause of prostate cancer. The most critical clinical challenge in the management of the patients is identifying those individuals at risk of developing metastatic disease. To understand the molecular mechanisms of prostate cancer metastasis and identify markers with metastatic potential, we have analyzed protein expression in two syngeneic prostate cancer cells lines PC3-N2 and PC3-ML2 using isobaric tags for relative and absolute quantitation labeling and multi-dimensional protein identification technology liquid chromatography matrix assisted laser desorption ionization tandem mass spectrometry. PC3-N2 is lowly metastatic while PC3-ML2 highly metastatic. A total of 1,756 proteins were identified in the analyses with 130 proteins showing different expression levels (p<0.01) in the two cell lines. Out of these, 68 proteins were found to be significantly up-regulated while 62 are significantly down-regulated in PC3-ML2 cells compared with PC3-N2 cells. The upregulation of plectin and vimentin which were the most significantly differentially expressed were validated by Western blot and their functional relevance with respect to invasion and migration was determined by siRNA gene silencing. To our knowledge, this study is the first to demonstrate that up-regulation of vimentin and plectin expression positively correlates with the invasion and metastasis of androgen-independent PCA.
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Affiliation(s)
- Tanya C. Burch
- Department of Microbiology and Molecular Cell Biology, Eastern Virginia Medical School, Norfolk, Virginia, United States of America
- Leroy T. Canoles Jr. Cancer Research Center, Eastern Virginia Medical School, Norfolk, Virginia, United States of America
| | - Megan T. Watson
- Department of Microbiology and Molecular Cell Biology, Eastern Virginia Medical School, Norfolk, Virginia, United States of America
- Leroy T. Canoles Jr. Cancer Research Center, Eastern Virginia Medical School, Norfolk, Virginia, United States of America
| | - Julius O. Nyalwidhe
- Department of Microbiology and Molecular Cell Biology, Eastern Virginia Medical School, Norfolk, Virginia, United States of America
- Leroy T. Canoles Jr. Cancer Research Center, Eastern Virginia Medical School, Norfolk, Virginia, United States of America
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