1
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Sfakianos AP, Raven RM, Willis AE. The pleiotropic roles of eIF5A in cellular life and its therapeutic potential in cancer. Biochem Soc Trans 2022; 50:1885-1895. [PMID: 36511302 PMCID: PMC9788402 DOI: 10.1042/bst20221035] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2022] [Revised: 11/28/2022] [Accepted: 11/30/2022] [Indexed: 11/19/2023]
Abstract
Protein synthesis is dysregulated in the majority of cancers and this process therefore provides a good therapeutic target. Many novel anti-cancer agents are directed to target the initiation stage of translation, however, translation elongation also holds great potential as a therapeutic target. The elongation factor eIF5A that assists the formation of peptidyl bonds during the elongation process is of considerable interest in this regard. Overexpression of eIF5A has been linked with the development of a variety of cancers and inhibitors of the molecule have been proposed for anti-cancer clinical applications. eIF5A is the only protein in the cell that contains the post-translational modification hypusine. Hypusination is a two-step enzymatic process catalysed by the Deoxyhypusine Synthase (DHPS) and Deoxyhypusine Hydroxylase (DOHH). In addition, eIF5A can be acetylated by p300/CBP-associated factor (PCAF) which leads to translocation of the protein to the nucleus and its deactivation. In addition to the nucleus, eIF5A has been found in the mitochondria and the endoplasmic reticulum (ER) with eIF5A localisation related to function from regulation of mitochondrial activity and apoptosis to maintenance of ER integrity and control of the unfolded protein response (UPR). Given the pleiotropic functions of eIF5A and by extension the hypusination enzymes, this system is being considered as a target for a range of cancers including multiple myeloma, B-Cell lymphoma, and neuroblastoma. In this review, we explore the role of eIF5A and discuss the therapeutic strategies that are currently developing both in the pre- and the clinical stage.
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Affiliation(s)
| | - Rebecca Mallory Raven
- MRC Toxicology Unit, University of Cambridge, Gleeson Building, Tennis Court Rd, Cambridge, U.K
| | - Anne Elizabeth Willis
- MRC Toxicology Unit, University of Cambridge, Gleeson Building, Tennis Court Rd, Cambridge, U.K
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2
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Kaiser A, Agostinelli E. Hypusinated EIF5A as a feasible drug target for Advanced Medicinal Therapies in the treatment of pathogenic parasites and therapy-resistant tumors. Amino Acids 2022; 54:501-511. [DOI: 10.1007/s00726-021-03120-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2021] [Accepted: 12/21/2021] [Indexed: 11/30/2022]
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3
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Tauc M, Cougnon M, Carcy R, Melis N, Hauet T, Pellerin L, Blondeau N, Pisani DF. The eukaryotic initiation factor 5A (eIF5A1), the molecule, mechanisms and recent insights into the pathophysiological roles. Cell Biosci 2021; 11:219. [PMID: 34952646 PMCID: PMC8705083 DOI: 10.1186/s13578-021-00733-y] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2021] [Accepted: 12/14/2021] [Indexed: 11/29/2022] Open
Abstract
Since the demonstration of its involvement in cell proliferation, the eukaryotic initiation factor 5A (eIF5A) has been studied principally in relation to the development and progression of cancers in which the isoform A2 is mainly expressed. However, an increasing number of studies report that the isoform A1, which is ubiquitously expressed in normal cells, exhibits novel molecular features that reveal its new relationships between cellular functions and organ homeostasis. At a first glance, eIF5A can be regarded, among other things, as a factor implicated in the initiation of translation. Nevertheless, at least three specificities: (1) its extreme conservation between species, including plants, throughout evolution, (2) its very special and unique post-translational modification through the activating-hypusination process, and finally (3) its close relationship with the polyamine pathway, suggest that the role of eIF5A in living beings remains to be uncovered. In fact, and beyond its involvement in facilitating the translation of proteins containing polyproline residues, eIF5A is implicated in various physiological processes including ischemic tolerance, metabolic adaptation, aging, development, and immune cell differentiation. These newly discovered physiological properties open up huge opportunities in the clinic for pathologies such as, for example, the ones in which the oxygen supply is disrupted. In this latter case, organ transplantation, myocardial infarction or stroke are concerned, and the current literature defines eIF5A as a new drug target with a high level of potential benefit for patients with these diseases or injuries. Moreover, the recent use of genomic and transcriptomic association along with metadata studies also revealed the implication of eIF5A in genetic diseases. Thus, this review provides an overview of eIF5A from its molecular mechanism of action to its physiological roles and the clinical possibilities that have been recently reported in the literature.
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Affiliation(s)
- Michel Tauc
- LP2M, CNRS, Université Côte d'Azur, Nice, France. .,Laboratories of Excellence Ion Channel Science and Therapeutics, Nice, France. .,Laboratoire de Physiomédecine Moléculaire, UMR7370, Faculté de Médecine, CNRS, Université Côte d'Azur, 28 Avenue de Valombrose, 06107, Nice Cedex, France.
| | - Marc Cougnon
- LP2M, CNRS, Université Côte d'Azur, Nice, France.,Laboratories of Excellence Ion Channel Science and Therapeutics, Nice, France
| | - Romain Carcy
- Service de Réanimation Polyvalente et Service de Réanimation des Urgences Vitales, CHU Nice, Hôpital Pasteur 2, Nice, France
| | - Nicolas Melis
- Laboratory of Cellular and Molecular Biology, Center for Cancer Research, National Cancer Institute, Bethesda, MD, 20892, USA
| | - Thierry Hauet
- INSERM, IRTOMIT, CHU de Poitiers, Université de Poitiers, La Milétrie, Poitiers, France
| | - Luc Pellerin
- INSERM, IRTOMIT, CHU de Poitiers, Université de Poitiers, La Milétrie, Poitiers, France
| | - Nicolas Blondeau
- Laboratories of Excellence Ion Channel Science and Therapeutics, Nice, France.,IPMC, CNRS, Université Côte d'Azur, Valbonne, France
| | - Didier F Pisani
- LP2M, CNRS, Université Côte d'Azur, Nice, France.,Laboratories of Excellence Ion Channel Science and Therapeutics, Nice, France
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4
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Tanaka Y, Kurasawa O, Yokota A, Klein MG, Saito B, Matsumoto S, Okaniwa M, Ambrus-Aikelin G, Uchiyama N, Morishita D, Kimura H, Imamura S. New Series of Potent Allosteric Inhibitors of Deoxyhypusine Synthase. ACS Med Chem Lett 2020; 11:1645-1652. [PMID: 34345355 PMCID: PMC8323115 DOI: 10.1021/acsmedchemlett.0c00331] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2020] [Accepted: 07/30/2020] [Indexed: 02/06/2023] Open
Abstract
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Deoxyhypusine synthase (DHPS) is
the primary enzyme responsible
for the hypusine modification and, thereby, activation of the eukaryotic
translation initiation factor 5A (eIF5A), which is key in regulating
the protein translation processes associated with tumor proliferation.
Although DHPS inhibitors could be a promising therapeutic option for
treating cancer, only a few studies reported druglike compounds with
this inhibition property. Thus, in this work, we designed and synthesized
a new chemical series possessing fused ring scaffolds designed from
high-throughput screening hit compounds, discovering a 5,6-dihydrothieno[2,3-c]pyridine derivative (26d) with potent inhibitory
activity; furthermore, the X-ray crystallographic analysis of the
DHPS complex with 26d demonstrated a distinct allosteric
binding mode compared to a previously reported inhibitor. These findings
could be significantly useful in the functional analysis of conformational
changes in DHPS as well as the structure-based design of allosteric
inhibitors.
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Affiliation(s)
- Yuta Tanaka
- Pharmaceutical Research Division, Takeda Pharmaceutical Company Limited, 26-1, Muraoka-Higashi 2-chome, Fujisawa, Kanagawa 251-8555, Japan
| | - Osamu Kurasawa
- Pharmaceutical Research Division, Takeda Pharmaceutical Company Limited, 26-1, Muraoka-Higashi 2-chome, Fujisawa, Kanagawa 251-8555, Japan
| | - Akihiro Yokota
- Pharmaceutical Research Division, Takeda Pharmaceutical Company Limited, 26-1, Muraoka-Higashi 2-chome, Fujisawa, Kanagawa 251-8555, Japan
| | - Michael G. Klein
- Department of Structural Biology, Takeda California, 10410 Science Center Drive, San Diego, California 92121, United States
| | - Bunnai Saito
- Pharmaceutical Research Division, Takeda Pharmaceutical Company Limited, 26-1, Muraoka-Higashi 2-chome, Fujisawa, Kanagawa 251-8555, Japan
| | - Shigemitsu Matsumoto
- Pharmaceutical Research Division, Takeda Pharmaceutical Company Limited, 26-1, Muraoka-Higashi 2-chome, Fujisawa, Kanagawa 251-8555, Japan
| | - Masanori Okaniwa
- Pharmaceutical Research Division, Takeda Pharmaceutical Company Limited, 26-1, Muraoka-Higashi 2-chome, Fujisawa, Kanagawa 251-8555, Japan
| | - Geza Ambrus-Aikelin
- Department of Structural Biology, Takeda California, 10410 Science Center Drive, San Diego, California 92121, United States
| | - Noriko Uchiyama
- Pharmaceutical Research Division, Takeda Pharmaceutical Company Limited, 26-1, Muraoka-Higashi 2-chome, Fujisawa, Kanagawa 251-8555, Japan
| | - Daisuke Morishita
- Pharmaceutical Research Division, Takeda Pharmaceutical Company Limited, 26-1, Muraoka-Higashi 2-chome, Fujisawa, Kanagawa 251-8555, Japan
| | - Hiromichi Kimura
- Pharmaceutical Research Division, Takeda Pharmaceutical Company Limited, 26-1, Muraoka-Higashi 2-chome, Fujisawa, Kanagawa 251-8555, Japan
| | - Shinichi Imamura
- Pharmaceutical Research Division, Takeda Pharmaceutical Company Limited, 26-1, Muraoka-Higashi 2-chome, Fujisawa, Kanagawa 251-8555, Japan
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5
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Tanaka Y, Kurasawa O, Yokota A, Klein MG, Ono K, Saito B, Matsumoto S, Okaniwa M, Ambrus-Aikelin G, Morishita D, Kitazawa S, Uchiyama N, Ogawa K, Kimura H, Imamura S. Discovery of Novel Allosteric Inhibitors of Deoxyhypusine Synthase. J Med Chem 2020; 63:3215-3226. [PMID: 32142284 DOI: 10.1021/acs.jmedchem.9b01979] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Deoxyhypusine synthase (DHPS) utilizes spermidine and NAD as cofactors to incorporate a hypusine modification into the eukaryotic translation initiation factor 5A (eIF5A). Hypusine is essential for eIF5A activation, which, in turn, plays a key role in regulating protein translation of selected mRNA that are associated with the synthesis of oncoproteins, thereby enhancing tumor cell proliferation. Therefore, inhibition of DHPS is a promising therapeutic option for the treatment of cancer. To discover novel lead compounds that target DHPS, we conducted synthetic studies with a hit obtained via high-throughput screening. Optimization of the ring structures of the amide compound (2) led to bromobenzothiophene (11g) with potent inhibitory activity against DHPS. X-ray crystallographic analysis of 11g complexed with DHPS revealed a dramatic conformational change in DHPS, which suggests the presence of a novel allosteric site. These findings provide the basis for the development of novel therapy distinct from spermidine mimetic inhibitors.
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Affiliation(s)
- Yuta Tanaka
- Pharmaceutical Research Division, Takeda Pharmaceutical Company Limited, 26-1, Muraoka-Higashi 2-chome, Fujisawa, Kanagawa 251-8555, Japan
| | - Osamu Kurasawa
- Pharmaceutical Research Division, Takeda Pharmaceutical Company Limited, 26-1, Muraoka-Higashi 2-chome, Fujisawa, Kanagawa 251-8555, Japan
| | - Akihiro Yokota
- Pharmaceutical Research Division, Takeda Pharmaceutical Company Limited, 26-1, Muraoka-Higashi 2-chome, Fujisawa, Kanagawa 251-8555, Japan
| | - Michael G Klein
- Department of Structural Biology, Takeda California, 10410 Science Center Drive, San Diego, California 92121, United States
| | - Koji Ono
- Pharmaceutical Research Division, Takeda Pharmaceutical Company Limited, 26-1, Muraoka-Higashi 2-chome, Fujisawa, Kanagawa 251-8555, Japan
| | - Bunnai Saito
- Pharmaceutical Research Division, Takeda Pharmaceutical Company Limited, 26-1, Muraoka-Higashi 2-chome, Fujisawa, Kanagawa 251-8555, Japan
| | - Shigemitsu Matsumoto
- Pharmaceutical Research Division, Takeda Pharmaceutical Company Limited, 26-1, Muraoka-Higashi 2-chome, Fujisawa, Kanagawa 251-8555, Japan
| | - Masanori Okaniwa
- Pharmaceutical Research Division, Takeda Pharmaceutical Company Limited, 26-1, Muraoka-Higashi 2-chome, Fujisawa, Kanagawa 251-8555, Japan
| | - Geza Ambrus-Aikelin
- Department of Structural Biology, Takeda California, 10410 Science Center Drive, San Diego, California 92121, United States
| | - Daisuke Morishita
- Pharmaceutical Research Division, Takeda Pharmaceutical Company Limited, 26-1, Muraoka-Higashi 2-chome, Fujisawa, Kanagawa 251-8555, Japan
| | - Satoshi Kitazawa
- Pharmaceutical Research Division, Takeda Pharmaceutical Company Limited, 26-1, Muraoka-Higashi 2-chome, Fujisawa, Kanagawa 251-8555, Japan
| | - Noriko Uchiyama
- Pharmaceutical Research Division, Takeda Pharmaceutical Company Limited, 26-1, Muraoka-Higashi 2-chome, Fujisawa, Kanagawa 251-8555, Japan
| | - Kazumasa Ogawa
- Pharmaceutical Research Division, Takeda Pharmaceutical Company Limited, 26-1, Muraoka-Higashi 2-chome, Fujisawa, Kanagawa 251-8555, Japan
| | - Hiromichi Kimura
- Pharmaceutical Research Division, Takeda Pharmaceutical Company Limited, 26-1, Muraoka-Higashi 2-chome, Fujisawa, Kanagawa 251-8555, Japan
| | - Shinichi Imamura
- Pharmaceutical Research Division, Takeda Pharmaceutical Company Limited, 26-1, Muraoka-Higashi 2-chome, Fujisawa, Kanagawa 251-8555, Japan
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6
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Meng QB, Peng JJ, Qu ZW, Zhu XM, Wen Z, Kang WM. Eukaryotic initiation factor 5A2 and human digestive system neoplasms. World J Gastrointest Oncol 2019; 11:449-458. [PMID: 31236196 PMCID: PMC6580320 DOI: 10.4251/wjgo.v11.i6.449] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/31/2018] [Revised: 04/17/2019] [Accepted: 05/04/2019] [Indexed: 02/05/2023] Open
Abstract
Eukaryotic initiation factor 5A2 (eIF5A2), as one of the two isoforms in the family, is reported to be a novel oncogenic protein that is involved in multiple aspects of many types of human cancer. Overexpression or gene amplification of EIF5A2 has been demonstrated in many cancers. Accumulated evidence shows that eIF5A2 initiates tumor formation, enhances cancer cell growth, increases cancer cell metastasis, and promotes treatment resistance through multiple means, including inducing epithelial–mesenchymal transition, cytoskeletal rearrangement, angiogenesis, and metabolic reprogramming. Expression of eIF5A2 in cancer correlates with poor survival, advanced disease stage, as well as metastasis, suggesting that eIF5A2 function is crucial for tumor development and maintenance but not for normal tissue homeostasis. All these studies suggest that eIF5A2 is a useful biomarker in the prediction of cancer prognosis and serves as an anticancer molecular target. This review focuses on the expression, subcellular localization, post-translational modifications, and regulatory networks of eIF5A2, as well as its biochemical functions and evolving clinical applications in cancer, especially in human digestive system neoplasms.
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Affiliation(s)
- Qing-Bin Meng
- Department of Gastrointestinal Surgery, the First Hospital of Wuhan City, Wuhan 430022, Hubei Province, China
| | - Jing-Jing Peng
- Department of Gastroenterology, General Hospital of the Yangtze River Shipping, Wuhan 430015, Hubei Province, China
| | - Zi-Wei Qu
- Department of Gastrointestinal Surgery, the First Hospital of Wuhan City, Wuhan 430022, Hubei Province, China
| | | | - Zhang Wen
- Department of Hepato-Biliary-Pancreatic Surgery and Liver Transplantation, the First Affiliated Hospital of Guangxi Medical University, Nanning 530021, Guangxi Zhuang Autonomous Region, China
| | - Wei-Ming Kang
- Department of General Surgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100730, China
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7
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Turpaev KT. Translation Factor eIF5A, Modification with Hypusine and Role in Regulation of Gene Expression. eIF5A as a Target for Pharmacological Interventions. BIOCHEMISTRY. BIOKHIMIIA 2018; 83:863-873. [PMID: 30208826 DOI: 10.1134/s0006297918080011] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2018] [Revised: 04/09/2018] [Indexed: 12/22/2022]
Abstract
Translation factor eIF5A participates in protein synthesis at the stage of polypeptide chain elongation. Two eIF5A isoforms are known that are encoded by related genes whose expression varies significantly in different tissues. The eIF5A1 isoform is a constitutively and ubiquitously expressed gene, while the eIF5A2 isoform is expressed in few normal tissues and is an oncogene by a number of parameters. Unique feature of eIF5A isoforms is that they are the only two proteins that contain amino acid hypusine. Modification with hypusine is critical requirement for eIF5A activity. Another distinctive feature of eIF5A is its involvement in the translation of only a subset of the total population of cell mRNAs. The genes for which mRNAs translation requires eIF5A are the members of certain functional groups and are involved in cell proliferation, apoptosis, inflammatory processes, and regulation of transcription and RNA metabolism. The involvement of eIF5A is necessary for the translation of proteins containing oligoproline fragments and some other structures. Modification of eIF5A by hypusine is implemented by two highly specialized enzymes, deoxyhypusine synthase (DHS) and deoxyhypusine hydroxylase (DOHH), which are not involved in other biochemical reactions. Intracellular activity of these enzymes is closely associated with systems of protein acetylation, polyamine metabolism and other biochemical processes. Inhibition of DHS and DOHH activity provides the possibility of pharmacological control of eIF5A activity and expression of eIF5A-dependent genes.
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Affiliation(s)
- K T Turpaev
- Center for Theoretical Problems of Physicochemical Pharmacology, Russian Academy of Sciences, Moscow, 119991, Russia.
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8
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Schröder M, Kolodzik A, Windshügel B, Krepstakies M, Priyadarshini P, Hartjen P, van Lunzen J, Rarey M, Hauber J, Meier C. Linker-Region Modified Derivatives of the Deoxyhypusine Synthase Inhibitor CNI-1493 Suppress HIV-1 Replication. Arch Pharm (Weinheim) 2016; 349:91-103. [PMID: 26725082 DOI: 10.1002/ardp.201500323] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2015] [Revised: 12/02/2015] [Accepted: 12/04/2015] [Indexed: 11/12/2022]
Abstract
The inhibition of cellular factors that are involved in viral replication may be an important alternative to the commonly used strategy of targeting viral enzymes. The guanylhydrazone CNI-1493, a potent inhibitor of the deoxyhypusine synthase (DHS), prevents the activation of the cellular factor eIF-5A and thereby suppresses HIV replication and a number of other diseases. Here, we report on the design, synthesis and biological evaluation of a series of CNI-1493 analogues. The sebacoyl linker in CNI-1493 was replaced by different alkyl or aryl dicarboxylic acids. Most of the tested derivatives suppress HIV-1 replication efficiently in a dose-dependent manner without showing toxic side effects. The unexpected antiviral activity of the rigid derivatives point to a second binding mode as previously assumed for CNI-1493. Moreover, the chemical stability of CNI-1493 was analysed, showing a successive hydrolysis of the imino bonds. By molecular dynamics simulations, the behaviour of the parent CNI-1493 in solution and its interactions with DHS were investigated.
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Affiliation(s)
- Marcus Schröder
- Institute of Organic Chemistry, Department of Chemistry, Faculty of Sciences, University of Hamburg, Hamburg, Germany
| | - Adrian Kolodzik
- ZBH Center for Bioinformatics, University of Hamburg, Hamburg, Germany
| | - Björn Windshügel
- ZBH Center for Bioinformatics, University of Hamburg, Hamburg, Germany
| | - Marcel Krepstakies
- Heinrich Pette Institute - Leibniz Institute for Experimental Virology, Hamburg, Germany
| | - Poornima Priyadarshini
- Heinrich Pette Institute - Leibniz Institute for Experimental Virology, Hamburg, Germany
| | - Philip Hartjen
- Department of Medicine, Infectious Diseases Unit, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Jan van Lunzen
- Department of Medicine, Infectious Diseases Unit, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Matthias Rarey
- ZBH Center for Bioinformatics, University of Hamburg, Hamburg, Germany
| | - Joachim Hauber
- Heinrich Pette Institute - Leibniz Institute for Experimental Virology, Hamburg, Germany
| | - Chris Meier
- Institute of Organic Chemistry, Department of Chemistry, Faculty of Sciences, University of Hamburg, Hamburg, Germany
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9
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Mathews MB, Hershey JWB. The translation factor eIF5A and human cancer. BIOCHIMICA ET BIOPHYSICA ACTA 2015; 1849:836-44. [PMID: 25979826 PMCID: PMC4732523 DOI: 10.1016/j.bbagrm.2015.05.002] [Citation(s) in RCA: 121] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/06/2015] [Accepted: 05/06/2015] [Indexed: 12/14/2022]
Abstract
The eukaryotic initiation factor eIF5A is a translation factor that, unusually, has been assigned functions in both initiation and elongation. Additionally, it is implicated in transcription, mRNA turnover and nucleocytoplasmic transport. Two eIF5A isoforms are generated from distinct but related genes. The major isoform, eIF5A1, is considered constitutive, is abundantly expressed in most cells, and is essential for cell proliferation. The second isoform, eIF5A2, is expressed in few normal tissues but is highly expressed in many cancers and has been designated a candidate oncogene. Elevated expression of either isoform carries unfavorable prognostic implications for several cancers, and both have been advanced as cancer biomarkers. The amino acid hypusine, a presumptively unique eIF5A post-translational modification, is required for most known eIF5A functions and it renders eIF5A susceptible to inhibitors of the modification pathway as therapeutic targets. eIF5A has been shown to regulate a number of gene products specifically, termed the eIF5A regulon, and its role in translating proline-rich sequences has recently been identified. A model is advanced that accommodates eIF5A in both the initiation and elongation phases of translation. We review here the biochemical functions of eIF5A, the relationship of its isoforms with human cancer, and evolving clinical applications. This article is part of a Special Issue entitled: Translation and Cancer.
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Affiliation(s)
- Michael B Mathews
- Department of Medicine, Rutgers New Jersey Medical School, Newark, NJ 07103, USA.
| | - John W B Hershey
- Department of Biochemistry and Molecular Medicine, University of California Davis School of Medicine, Davis, CA 95616, USA.
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