Activation of Transmembrane Cell-Surface Receptors Via a Common Mechanism? the ‘‘Rotation Model’’

Total Page:16

File Type:pdf, Size:1020Kb

Activation of Transmembrane Cell-Surface Receptors Via a Common Mechanism? the ‘‘Rotation Model’’ Insights & Perspectives Hypotheses Activation of transmembrane cell-surface receptors via a common mechanism? The ‘‘rotation model’’ Ichiro N. Maruyama It has long been thought that transmembrane cell-surface receptors, such as typically consist of an extracellular receptor tyrosine kinases and cytokine receptors, among others, are activated by domain (ECD) and an intracellular ligand binding through ligand-induced dimerization of the receptors. However, domain (ICD) separated by a single transmembrane domain (TMD), with there is growing evidence that prior to ligand binding, various transmembrane the exception of bacterial receptors receptors have a preformed, yet inactive, dimeric structure on the cell surface. such as the aspartate receptor (Tar) Various studies also demonstrate that during transmembrane signaling, ligand and the serine receptor (Tsr), which binding to the extracellular domain of receptor dimers induces a rotation of have another TMD at their amino transmembrane domains, followed by rearrangement and/or activation of termini. Ligand binding to their ECDs often regulates kinases that are either intracellular domains. The paper here describes transmembrane cell-surface integrated into the receptor ICD, or receptors that are known or proposed to exist in dimeric form prior toligand binding, physically associated with the ICD. and discusses how these preformed dimers are activated by ligand binding. Apart from receptors that initiate signaling pathways inside cells via Keywords: tyrosine phosphorylation, there are .cytokine; dimerization; ligand binding; preformed dimer; transmembrane receptors in bacteria, fungi, and plants signaling; tyrosine kinase that phosphorylate histidine residues upon ligand binding. Furthermore, natriuretic peptide receptors, which are receptor-type guanylyl cyclases, Introduction cell membranes to the cytoplasm, and produce cGMP upon peptide binding. include receptor tyrosine kinases There are also receptors that recruit Transmembrane, cell-surface receptors (RTKs) and cytokine receptors among adaptor/effector proteins through transmit extracellular signals across many others. Cell-surface receptors protein-protein interactions upon ligand binding. There are two major, mutually DOI 10.1002/bies.201500041 exclusive concepts to explain activation of transmembrane, cell-surface receptors. Ligand binding induces Okinawa Institute of Science and Technology GCY-14, receptor-type guanylyl cyclase-14; Graduate University, Onna, Okinawa, Japan GHR, growth hormone receptor; ICD, intracellular either (i) dimerization of receptors, or domain; IGF1R, insulin-like growth factor-1 recep- (ii) rearrangement of constitutively pre- Corresponding author: tor; IL-6R, interleukin 6 receptor; IL-12R, inter- formed dimeric receptors. The former Ichiro N. Maruyama leukin 12 receptor; IR, insulin receptor; IRR, insulin E-mail: [email protected] receptor-related receptor; JAK, Janus kinase; mechanism, known as ligand-induced LepR, leptin receptor; NPRA, natriuretic peptide receptor dimerization, was first pro- Abbreviations: receptor A; p75NTR, neurotrophin receptor; PRLR, posed for the epidermal growth factor BRET, bioluminescence resonance energy trans- prolactin receptor; RTK, receptor tyrosine kinase; receptor (EGFR; also called ErbB1 or fer; ECD, extracellular domain; EGFR, epidermal STAT, signal transducers and activators of tran- growth factor receptor; Eph, ephrin receptor; scription; Tar, bacterial aspartate receptor; TLR, HER1) almost three decades ago [1–3]. In EpoR, erythropoietin receptor; ErbB, originally toll-like receptor; TMD, transmembrane domain; this “dimerization model,” the receptor named because of the homology to the erythro- TNFR, tumor necrosis factor receptor; TpoR, is thought to exist in monomeric form blastoma viral gene product, v-erbB; FGFR, thrombopoietin receptor; Trk, tropomyosin- fibroblast growth factor receptor; FnIII, fibronectin related kinase receptor; Tsr, bacterial serine on the cell surface prior to ligand type III; FRET, Forster€ resonance energy transfer; receptor. binding, which induces receptor Bioessays 37: 959–967, ß 2015 The Author. BioEssays published by WILEY Periodicals, Inc. This is an www.bioessays-journal.com 959 open access article under the terms of the Creative Commons Attribution-NonCommercial-NoDerivs License, which permits use and distribution in any medium, provided the original work is properly cited, the use is non-commercial and no modifications or adaptations are made. I. N. Maruyama Insights & Perspectives..... dimerization. According to this model, A variety of receptors kinase activity and in selective trans- ICDs of dimerized receptors are brought exist in dimeric form prior autophosphorylation of tyrosine resi- into close proximity to allow receptor to ligand binding dues. Some of these sites are involved in trans-autophosphorylation, subsequent maintaining active conformations of the tyrosine kinase activation, and initia- Receptor tyrosine kinases kinases, while others become docking tion of downstream signaling path- sites for various adaptor/effector scaf- ways [4, 5]. This mechanism has been The human RTK superfamily consists of fold proteins and enzymes. All RTKs, proposed for activation of many other 58 proteins grouped into 20 sub- except for the IR family, are expressed cell-surface receptors, including recep- families [8]. RTKs are integral mem- as single protomers. IR family members, tor tyrosine kinases and cytokine recep- brane proteins with a single TMD, and comprising IR, IGF1R, and IRR, are also tors. In contrast, the insulin receptor their N-terminal ECDs are generally expressed as single subunits, but they Hypotheses (IR), insulin-like growth factor-1 composed of various structural modules undergo processing into two a and two receptor (IGF1R), and insulin receptor- with multiple, intrachain, disulfide b polypeptide chains that are assembled related receptor (IRR) have covalent, bonds, and numerous N-linked into a heterotetramer, or an (ab)2 preformed, dimeric structures linked by glycosylation sites. Their ICDs have homodimer, stabilized by disulfide cysteine disulfide bridges [6, 7]. Like- tyrosine kinase domains flanked by bonds. wise, there is growing evidence that intracellular, juxtamembrane regions, prior to ligand binding, various trans- and C-terminal tails, which differ in size membrane receptors exist in preformed, and tyrosine content among family EGFR (ErbB) family yet inactive, dimeric form on the cell members. Ligand binding to the ECDs surface (Table 1). results in elevation of their tyrosine The ErbB receptor family consists of EGFR, ErbB2 (also known as Neu/ HER2), ErbB3 (HER3), and ErbB4 (HER4), and the receptors play crucial Table 1. Transmembrane cell-surface receptors that exist or are proposed to exist roles in cell growth, differentiation, in dimeric form prior to ligand binding survival, and migration. A number of studies demonstrate that prior to ligand References Rotation angle and reference binding, ErbB receptors exist in dimeric Receptor tyrosine kinases form on the cell surface (see [9], and EGFR [10–21] [140˚: 10] ErbB2 [13, 18, 80] references therein]. Chemical cross- ErbB3 [18, 21] linking showed that >80% of EGFR ErbB4 [18] molecules were dimeric in the absence EphA1 [40, 41] of bound ligand [10]. Forster€ resonance EphA2 [38, 39, 41] [60˚: 41] energy transfer (FRET) [11–14] and fluo- EphA3 [37] rescence correlation spectroscopic anal- FGFR3 [43] IGF1R [32] yses [13, 15, 16] further demonstrated that IR [32] preformed EGFR and ErbB2 dimers are IRR [33] present at physiological expression lev- MET [42] els on surfaces of living cells. Single- TrkA [28] molecule observations using total inter- TrkB [29] nal reflection fluorescence microscopy VEGFR2 [180˚: 99] with oblique illumination also supports Cytokine receptors EpoR [50, 51] [100˚: 91, 92] the existence of receptor dimers [17]. GHR [48, 49] [40˚: 93, 94; 45˚: 95] Fluorescent protein fragment comple- IL-6R [60] mentation indicates that all the members IL-12R [58] of the ErbB family exist in dimeric LepR [55–57] NTR form [18]. This is consistent with results p75 [30] of reversible firefly luciferase fragment PRLR [52] TNFR [62] complementation analysis, showing that TpoR [100˚: 53] 100% of EGFR and ErbB3 receptor Other cell-surface receptors molecules exist as dimers [19–21], since EnvZ [69] luciferase activity did not increase after GCY-14 [65] addition of EGF to the cell culture. LINGO-1 [66] Depending on methods used, dimer- NPRA [64] [40˚: 96] Tar [67] [50˚: 74] to-monomer ratios vary from 40 to TLR9 [63] 100%. Considering the inefficiency of Tsr [68] chemical cross-linking [22] and of fluo- rescent protein folding [23–25], these Receptors in which TMDs have been proposed to rotate during signaling are ratios are likely to be underestimated. indicated with bold letters, with or without rotation angles and reference(s). However, when EGFR mutants with 960 Bioessays 37: 959–967, ß 2015 The Author. BioEssays published by WILEY Periodicals, Inc. .....Insights & Perspectives I. N. Maruyama cysteine substitutions at different loca- extracellular a-subunits that contain (signal transducers and activators of tions in the TMD were expressed in a ligand-binding domains and two trans- transcription) proteins. A series of land- murine pre-B lymphocyte line, Ba/F3, membrane b-subunits that possess mark publications gave rise to the Hypotheses disulfide cross-linking of the receptors intracellular kinase domains [32, 33]. textbook view that ligand binding
Recommended publications
  • Somatic Ephrin Receptor Mutations Are Associated with Metastasis in Primary Colorectal Cancer Running Title
    Author Manuscript Published OnlineFirst on January 20, 2017; DOI: 10.1158/0008-5472.CAN-16-1921 Author manuscripts have been peer reviewed and accepted for publication but have not yet been edited. Uvyr)Thvp ru v rpr hv h r hpvhrq vu rhhv v vh py rphy phpr Svt vyr) 6u ) " #$ % & '$ $( $)*# $ ,$$ - ./ 0 1 " , $'2 / ' - , $$03$, 4, 5$ $ 6 7$ % & 8 8$ 9 6ssvyvhv) . 8 : .2 $ 5 1 $ ; $ ;# < %. 8 : ., , $ ;# $ < -: . $, 8 $ . . 8 ; $ ;# /. 8 : . $; $ ;# < 0= $ 1 2 . , >2,, $ ?&, $ 2 . & $ , $@ ABA%B, $ < 4: . $ $ $ ; $ ;# < 6: .2 $ 5 1 $ .@ $ $ $ = $ ; $ ;# < Downloaded from cancerres.aacrjournals.org on September 26, 2021. © 2017 American Association for Cancer Research. Author Manuscript Published OnlineFirst on January 20, 2017; DOI: 10.1158/0008-5472.CAN-16-1921 Author manuscripts have been peer reviewed and accepted for publication but have not yet been edited. & 8 * $$ < 9& $8 C 8 < 8$ D< < 8syvp s vr rC & . $@ $, $ ', $E $ . $ 8$:7'@ < % Downloaded from cancerres.aacrjournals.org on September 26, 2021. © 2017 American Association for Cancer Research. Author Manuscript Published OnlineFirst on January 20, 2017; DOI: 10.1158/0008-5472.CAN-16-1921 Author manuscripts have been peer reviewed and accepted for publication but have not yet been edited. 6i hpC& 8 . . $ $ >? $ <& . # $# . $ $ .464A6 22)2 . $. E<& # $ >?. $ . ). $ . ) . $$ 222 2 < $ $ . @ . <& 8$. $ ., ::)$$@,. ) $ ),@$$<F .8 222 . , $) ,::)$$ ), $E <& 8# # $8 , < - Downloaded from cancerres.aacrjournals.org on September 26, 2021. © 2017 American Association for Cancer Research. Author Manuscript Published OnlineFirst on January 20, 2017; DOI: 10.1158/0008-5472.CAN-16-1921 Author manuscripts have been peer reviewed and accepted for publication but have not yet been edited. D qpv #$ .$$) $ .. 8 >&5?>?<& . 8@ #$ $#$ # $ 8$ .8 .
    [Show full text]
  • Eph Receptor Signalling: from Catalytic to Non-Catalytic Functions
    Oncogene (2019) 38:6567–6584 https://doi.org/10.1038/s41388-019-0931-2 REVIEW ARTICLE Eph receptor signalling: from catalytic to non-catalytic functions 1,2 1,2 3 1,2 1,2 Lung-Yu Liang ● Onisha Patel ● Peter W. Janes ● James M. Murphy ● Isabelle S. Lucet Received: 20 March 2019 / Revised: 23 July 2019 / Accepted: 24 July 2019 / Published online: 12 August 2019 © The Author(s) 2019. This article is published with open access Abstract Eph receptors, the largest subfamily of receptor tyrosine kinases, are linked with proliferative disease, such as cancer, as a result of their deregulated expression or mutation. Unlike other tyrosine kinases that have been clinically targeted, the development of therapeutics against Eph receptors remains at a relatively early stage. The major reason is the limited understanding on the Eph receptor regulatory mechanisms at a molecular level. The complexity in understanding Eph signalling in cells arises due to following reasons: (1) Eph receptors comprise 14 members, two of which are pseudokinases, EphA10 and EphB6, with relatively uncharacterised function; (2) activation of Eph receptors results in dimerisation, oligomerisation and formation of clustered signalling centres at the plasma membrane, which can comprise different combinations of Eph receptors, leading to diverse downstream signalling outputs; (3) the non-catalytic functions of Eph receptors have been overlooked. This review provides a structural perspective of the intricate molecular mechanisms that 1234567890();,: 1234567890();,: drive Eph receptor signalling, and investigates the contribution of intra- and inter-molecular interactions between Eph receptors intracellular domains and their major binding partners. We focus on the non-catalytic functions of Eph receptors with relevance to cancer, which are further substantiated by exploring the role of the two pseudokinase Eph receptors, EphA10 and EphB6.
    [Show full text]
  • Systemic Analysis of Tyrosine Kinase Signaling Reveals a Common Adaptive Response Program in a HER2-Positive Breast Cancer
    Systemic analysis of tyrosine kinase signaling reveals a common adaptive response program in a HER2-positive breast cancer The MIT Faculty has made this article openly available. Please share how this access benefits you. Your story matters. Citation Schwill, Martin et al. "Systemic analysis of tyrosine kinase signaling reveals a common adaptive response program in a HER2-positive breast cancer." Science Signaling 12, 565 (January 2019): eaau2875 © 2019 The Author(s) As Published https://dx.doi.org/10.1126/scisignal.aau2875 Publisher American Association for the Advancement of Science (AAAS) Version Author's final manuscript Citable link https://hdl.handle.net/1721.1/125489 Terms of Use Creative Commons Attribution-Noncommercial-Share Alike Detailed Terms http://creativecommons.org/licenses/by-nc-sa/4.0/ HHS Public Access Author manuscript Author ManuscriptAuthor Manuscript Author Sci Signal Manuscript Author . Author manuscript; Manuscript Author available in PMC 2019 July 22. Published in final edited form as: Sci Signal. ; 12(565): . doi:10.1126/scisignal.aau2875. Systemic analysis of tyrosine kinase signaling reveals a common adaptive response program in a HER2-positive breast cancer Martin Schwill1, Rastislav Tamaskovic1, Aaron S. Gajadhar2, Florian Kast1, Forest M. White2, and Andreas Plückthun1,* 1Department of Biochemistry, University of Zurich, Winterthurerstr. 190, 8057 Zurich, Switzerland 2Department of Biological Engineering, Koch Institute for Integrative Cancer Research, Center for Precision Cancer Medicine, Massachusetts Institute of Technology, Cambridge, MA 02139, USA Abstract Drug-induced compensatory signaling and subsequent rewiring of the signaling pathways that support cell proliferation and survival promotes the development of acquired drug resistance in tumors. Here, we sought to analyze the adaptive kinase response in cancer cells after distinct treatment with agents targeting human epidermal growth factor receptor 2 (HER2), specifically those which induce only temporary cell cycle arrest or apoptosis in HER2-overexpressing cancers.
    [Show full text]
  • Tie2 and Eph Receptor Tyrosine Kinase Activation and Signaling
    Downloaded from http://cshperspectives.cshlp.org/ on September 26, 2021 - Published by Cold Spring Harbor Laboratory Press Tie2 and Eph Receptor Tyrosine Kinase Activation and Signaling William A. Barton1, Annamarie C. Dalton1, Tom C.M. Seegar1, Juha P. Himanen2, and Dimitar B. Nikolov2 1Department of Biochemistry and Molecular Biology, School of Medicine, Virginia Commonwealth University, Richmond, Virginia 23298 2Structural Biology Program, Memorial Sloan-Kettering Cancer Center, New York, New York 10065 Correspondence: [email protected] The Eph and Tie cell surface receptors mediate a variety of signaling events during develop- ment and in the adult organism. As other receptor tyrosine kinases, they are activated on binding of extracellular ligands and their catalytic activity is tightly regulated on multiple levels. The Eph and Tie receptors display some unique characteristics, including the require- ment of ligand-induced receptor clustering for efficient signaling. Interestingly, both Ephs and Ties can mediate different, even opposite, biological effects depending on the specific ligand eliciting the response and on the cellular context. Here we discuss the structural features of these receptors, their interactions with various ligands, as well as functional implications for downstream signaling initiation. The Eph/ephrin structures are already well reviewed and we only provide a brief overview on the initial binding events. We go into more detail discussing the Tie-angiopoietin structures and recognition. ANGIOPOIETINS AND TIE2 In contrast tovasculogenesis, angiogenesis is asculogenesis and angiogenesis are distinct continually required in the adult for wound re- Vcellular processes essential to the creation of pairand remodeling of reproductive tissues dur- the adult vasculature. In early embryonic devel- ing female menstruation.
    [Show full text]
  • Tyrosine Kinase Inhibitors in Cancer: Breakthrough and Challenges of Targeted Therapy
    cancers Review Tyrosine Kinase Inhibitors in Cancer: Breakthrough and Challenges of Targeted Therapy 1,2, 3,4 1 2 3, Charles Pottier * , Margaux Fresnais , Marie Gilon , Guy Jérusalem ,Rémi Longuespée y 1, and Nor Eddine Sounni y 1 Laboratory of Tumor and Development Biology, GIGA-Cancer and GIGA-I3, GIGA-Research, University Hospital of Liège, 4000 Liège, Belgium; [email protected] (M.G.); [email protected] (N.E.S.) 2 Department of Medical Oncology, University Hospital of Liège, 4000 Liège, Belgium; [email protected] 3 Department of Clinical Pharmacology and Pharmacoepidemiology, University Hospital of Heidelberg, 69120 Heidelberg, Germany; [email protected] (M.F.); [email protected] (R.L.) 4 German Cancer Consortium (DKTK)-German Cancer Research Center (DKFZ), 69120 Heidelberg, Germany * Correspondence: [email protected] Equivalent contribution. y Received: 17 January 2020; Accepted: 16 March 2020; Published: 20 March 2020 Abstract: Receptor tyrosine kinases (RTKs) are key regulatory signaling proteins governing cancer cell growth and metastasis. During the last two decades, several molecules targeting RTKs were used in oncology as a first or second line therapy in different types of cancer. However, their effectiveness is limited by the appearance of resistance or adverse effects. In this review, we summarize the main features of RTKs and their inhibitors (RTKIs), their current use in oncology, and mechanisms of resistance. We also describe the technological advances of artificial intelligence, chemoproteomics, and microfluidics in elaborating powerful strategies that could be used in providing more efficient and selective small molecules inhibitors of RTKs.
    [Show full text]
  • Cshperspect-RTK-Index 469..478
    Index A endothelial cell-derived tumors, 396 Abl, kinase modulation by SH2 metastasis studies, 394 allosteric activation, 39–40 tumor vascularization, 393–394 inhibition by intramolecular interactions, 38–39 development Acetylcholine receptor (AChR) endothelial cell expression of receptors muscle-specific kinase interactions, 265–268 Tie receptors, 392–393 myasthenia gravis autoantibodies, 271–272 vascular endothelial growth factor AChR. See Acetylcholine receptor receptor, 391–392 Acute myeloid leukemia, Kit role, 217 overview, 387–388 ADAM proteases inhibition for therapy, 396–400 domain structure, 119–120 lymphangiogenesis defects in lymphedema, 375 ephrin cleavage, 312 prospects for study, 400 epidermal growth factor receptor ligand therapeutic angiogenesis, 394–395 shedding role, 120–121 tip and stalk cell expression of receptor shedding tyrosine kinases, 389 stimuli, 121–122 vascular malformations, 396 tetraspanins in spatial control, 122–123 Angiopoietins ADAM10 Ang2 signals in inflammation, 395–396 ephrin proteolysis, 126 angiogenesis role, 391 platelet-derived growth factor receptor functional overview, 287–288 ligand proteolysis, 126 inhibitor therapy, 399–400 ADAM12, ErbB2 expression regulation, 140 knockout mouse, 392–393 ADAM17 (TACE) structure, 288–289 activity regulation in plasma membrane, 122 vascular endothelial growth factor receptor ErbB-4 as substrate, 50–51, 68–69 signaling cross talk, 234 trafficking regulators, 123 Apoptosis, TAM receptors in cell clearance, 373–374 Agrin, Lrp4 binding, 265, 269–270 Atherosclerosis, platelet-derived growth factor Akt receptor role, 214 ephrin receptor signaling, 310–311 Axl. See TAM receptors Grb2 in signaling, 38 insulin receptor signaling, 412–413 insulin resistance defects, 420 B MET signaling, 437 BCR-ABL RET signaling, 280–281 chronic myelogenous leukemia, 17–18 TAM receptor signaling, 371 therapeutic targeting, 18 Alk.
    [Show full text]
  • Epha2 and EGFR: Friends in Life, Partners in Crime
    cancers Review EphA2 and EGFR: Friends in Life, Partners in Crime. Can EphA2 Be a Predictive Biomarker of Response to Anti-EGFR Agents? Mario Cioce 1,* and Vito Michele Fazio 1,2,3,* 1 Laboratory of Molecular Medicine and Biotechnology, Department of Medicine, University Campus Bio-Medico of Rome, 00128 Rome, Italy 2 Laboratory of Oncology, Fondazione IRCCS Casa Sollievo della Sofferenza, 71013 San Giovanni Rotondo, Italy 3 Institute of Translational Pharmacology, National Research Council of Italy (CNR), 00133 Rome, Italy * Correspondence: [email protected] (M.C.); [email protected] (V.M.F.) Simple Summary: The Ephrin receptors and their ligands play important roles in organ formation and tissue repair, by orchestrating complex programs of cell adhesion and repulsion, however, this same system plays a role in cancer development In fact, EphA2 levels are higher in tumors vs normal tissue and further increased upon treatment, in vivo and in vitro. Changes in the molecular status of EphA2, of its subcellular localization, the absence of ligand and signals derived from the tumor context unleash the oncogenic role of EphA2 and its broad ability to promote resistance to radiotherapy, chemotherapy and targeted agents, including inhibitors of Epidermal-Growth-Factor- Receptor (EGFR). High levels of EphA2 may reduce response to cetuximab even in RAS wt CRC patients. In this work, we aim to review the current knowledge of the EphA2 function which is crucial for achieving a more effective therapeutic management of tumors resistant to EGFR inhibitors and to many other agents. Abstract: The Eph receptors represent the largest group among Receptor Tyrosine kinase (RTK) Citation: Cioce, M.; Fazio, V.M.
    [Show full text]
  • Harnessing the Power of Eph/Ephrin Biosemiotics for Theranostic Applications
    pharmaceuticals Review Harnessing the Power of Eph/ephrin Biosemiotics for Theranostic Applications Robert M. Hughes 1 and Jitka A.I. Virag 2,* 1 Department of Chemistry, East Carolina University, Science and Technology Building, SZ564, East 5th St, Greenville, NC 27858, USA; [email protected] 2 Department of Physiology, Brody School of Medicine, East Carolina University, Warren Life Sciences Building, LSB239, 600 Moye Blvd, Greenville, NC 27834, USA * Correspondence: [email protected] Received: 11 April 2020; Accepted: 27 May 2020; Published: 1 June 2020 Abstract: Comprehensive basic biological knowledge of the Eph/ephrin system in the physiologic setting is needed to facilitate an understanding of its role and the effects of pathological processes on its activity, thereby paving the way for development of prospective therapeutic targets. To this end, this review briefly addresses what is currently known and being investigated in order to highlight the gaps and possible avenues for further investigation to capitalize on their diverse potential. Keywords: Eph/ephrin; receptor tyrosine kinase; therapeutic target; smart drug; nanoparticles; liposomes; exosomes 1. Introduction Detection, transduction and appropriate response behavior of neighboring cells are essential components of optimal communication and the coordinated and integrated function necessary for survival. In a complex system, this is determined by the summative and timely intracellular processing of a myriad of intersecting signals from various distances and directions. The Eph receptors and ephrin ligands are the largest tyrosine kinase (RTK) superfamily, comprised of 22 known members, subdivided into A- and B-subclasses, and are heterogeneously expressed in almost every tissue [1]. These membrane-anchored proteins exhibit unique cell-to-cell communication via bidirectional signaling, which modulates cytoskeletal dynamics and thus cell–cell recognition and motility, making them integral mediators in developmental processes and the maintenance of homeostasis [2,3].
    [Show full text]
  • The Role of the Eph Receptor Family in Tumorigenesis. Cancers 2021
    cancers Review The Role of the Eph Receptor Family in Tumorigenesis Meg Anderton 1,2 , Emma van der Meulen 1,2 , Melissa J. Blumenthal 1,2,3,* and Georgia Schäfer 1,2,3,* 1 International Centre for Genetic Engineering and Biotechnology (ICGEB) Cape Town, Observatory, Cape Town 7925, South Africa; [email protected] (M.A.); [email protected] (E.v.d.M.) 2 Institute of Infectious Disease and Molecular Medicine (IDM), Faculty of Health Sciences, University of Cape Town, Observatory, Cape Town 7925, South Africa 3 Division of Medical Biochemistry and Structural Biology, Department of Integrative Biomedical Sciences, Faculty of Health Sciences, University of Cape Town, Observatory, Cape Town 7925, South Africa * Correspondence: [email protected] (M.J.B.); [email protected] (G.S.); Tel.: +27-21-4047630 (M.J.B.) Simple Summary: The Eph receptor family is implicated in both tumour promotion and suppression, depending on the tissue-specific context of available receptor interactions with ligands, adaptor proteins and triggered downstream signalling pathways. This complex interplay has not only consequences for tumorigenesis but also offers a basis from which new cancer-targeting strategies can be developed. This review comprehensively summarises the current knowledge of Eph receptor implications in oncogenesis in a tissue- and receptor-specific manner, with the aim to develop a better understanding of Eph signalling pathways for potential targeting in novel cancer therapies. Abstract: The Eph receptor tyrosine kinase family, activated by binding to their cognate ephrin ligands, are important components of signalling pathways involved in animal development. More recently, they have received significant interest due to their involvement in oncogenesis.
    [Show full text]
  • A Plausible Candidate Turning Off The
    RESEARCH HIGHLIGHTS IN THE NEWS METASTASIS Stress is good for you? Women who experience increased levels of stress A plausible candidate are less likely to develop breast cancer, according to a study by Danish Cancer mortality is most often the suppressor gene Brms1. However, GTPase activating protein (GAP) scientists (Nielsen, N. R. et result of metastasis rather than this gene has no obvious polymor- that negatively regulates RAP1 and al., Br. Med. J. 9 September the primary tumour. Previous phisms that influence metastasis RAP2 GTPases. Human SIPA1 has 2005 (doi: 10.1136/ studies from Kent Hunter’s group and so was discounted from this recently been found to interact bmj.38547.638183.06)). demonstrated that the genetic study. with the water channel aquaporin 2 Stress can reduce oestrogen production and background of the host can influ- To identify other potential can- (AQP2), by its PDZ domain, so the oestrogen is a known risk ence metastatic efficiency. Now, didates the authors used a multiple authors used AQP2 to see if the factor in breast cancer. Hunter and colleagues have identi- cross-mapping strategy that uses alanine to threonine substitution Therefore, the authors fied a candidate gene, Sipa1, with the shared haplotypes in different affected this interaction. They followed the incidence of an amino-acid polymorphism that inbred strains of mice to reduce the found that it did — the FVB allele breast cancer in the 6,689 influences this process. number of candidate genes. This bound AQP2 less effectively. women of the Copenhagen The authors previously used a reduced the number of potential What does this mean biologi- City Heart Study who had assessed their own stress mouse model of breast cancer to genes from 500 to 23, which were cally? Transient transfection assays levels between 1981 and investigate the effect of constitu- then prioritized based on their demonstrated that the FVB allele is 1983.
    [Show full text]
  • Phosphoproteomic Analysis of Her2 Neu Signaling and Inhibition
    Phosphoproteomic analysis of Her2͞neu signaling and inhibition Ron Bose*†, Henrik Molina‡, A. Scott Patterson§, John K. Bitok*, Balamurugan Periaswamy‡¶, Joel S. Baderʈ**, Akhilesh Pandey†‡††, and Philip A. Cole*†,†† Departments of *Pharmacology, †Oncology, and **Biomedical Engineering, ‡McKusick–Nathans Institute for Genetic Medicine, §Institute in Multiscale Modeling of Biological Interactions, and ʈHigh-Throughput Biology Center, Johns Hopkins University School of Medicine, Baltimore, MD 21205; and ¶Institute of Bioinformatics, International Tech Park, Bangalore 560066, India Communicated by Paul Talalay, Johns Hopkins University School of Medicine, Baltimore, MD, May 12, 2006 (received for review March 3, 2006) Her2͞neu (Her2) is a tyrosine kinase belonging to the EGF receptor signaling network, and Her2 is likely also to use a similarly complex (EGFR)͞ErbB family and is overexpressed in 20–30% of human network to mediate cell proliferation and transformation (4–6). breast cancers. We sought to characterize Her2 signal transduction Further knowledge of the Her2 signaling network could potentially pathways further by using MS-based quantitative proteomics. identify drug targets or approaches to treat trastuzumab resistance. Stably transfected cell lines overexpressing Her2 or empty vector MS-based quantitative proteomics is a valuable tool for charac- were generated, and the effect of an EGFR and Her2 selective terizing signaling pathways and generally utilizes stable isotopes to tyrosine kinase inhibitor, PD168393, on these cells was character- label cellular proteins. Stable isotopes are incorporated either by ized. Quantitative measurements were obtained on 462 proteins metabolic labeling, as in the SILAC (stable isotope labeling with by using the SILAC (stable isotope labeling with amino acids in cell amino acids in cell culture) method, or by chemical derivatization culture) method to monitor three conditions simultaneously.
    [Show full text]
  • AXL-Driven EMT State As a Targetable Conduit in Cancer Jane Antony1,2,3 and Ruby Yun-Ju Huang1,4,5
    Published OnlineFirst June 30, 2017; DOI: 10.1158/0008-5472.CAN-17-0392 Cancer Review Research AXL-Driven EMT State as a Targetable Conduit in Cancer Jane Antony1,2,3 and Ruby Yun-Ju Huang1,4,5 Abstract The receptor tyrosine kinase (RTK) AXL has been intrinsically further elucidation to define targetable conduits. Therapeuti- linked to epithelial–mesenchymal transition (EMT) and pro- cally, as AXL inhibition has shown EMT reversal and resensi- moting cell survival, anoikis resistance, invasion, and metas- tization to other tyrosine kinase inhibitors, mitotic inhibitors, tasis in several cancers. AXL signaling has been shown to and platinum-based therapy, there is a need to stratify patients directly affect the mesenchymal state and confer it with aggres- based on AXL dependence. This review elucidates the role of sive phenotype and drug resistance. Recently, the EMT gradient AXL in EMT-mediated oncogenesis and highlights the recipro- has also been shown to rewire the kinase signaling nodes that cal control between AXL signaling and the EMT state. In facilitate AXL–RTK cross-talk, protracted signaling, converging addition, we review the potential in inhibiting AXL for the on ERK, and PI3K axes. The molecular mechanisms under- development of different therapeutic strategies and inhibitors. playing the regulation between the kinome and EMT require Cancer Res; 77(14); 3725–32. Ó2017 AACR. Introduction was originally identified in 1991 as a transforming gene in chronic myeloid leukemia (CML; ref. 3). Under normal phys- AXL, which stems from the Greek word for uncontrolled, iologic conditions, it is ubiquitously expressed in several tissues "anexelekto," is a receptor tyrosine kinase (RTK) belonging to and organs, including but not limited to the hippocampus, the tumor-associated macrophage (TAM) family, comprising of cerebellum, macrophages, platelets, endothelial cells, heart, TYRO-3, AXL, and MER (Fig.
    [Show full text]