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Dinh VT, Loaëc N, Quillévéré A, Le Sénéchal R, Keruzoré M, Martins RP, Granzhan A, Blondel M. The hide-and-seek game of the oncogenic Epstein-Barr virus-encoded EBNA1 protein with the immune system: An RNA G-quadruplex tale. Biochimie 2023; 214:57-68. [PMID: 37473831 DOI: 10.1016/j.biochi.2023.07.010] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2023] [Revised: 07/11/2023] [Accepted: 07/13/2023] [Indexed: 07/22/2023]
Abstract
The Epstein-Barr virus (EBV) is the first oncogenic virus described in human. EBV infects more than 90% of the human population worldwide, but most EBV infections are asymptomatic. After the primary infection, the virus persists lifelong in the memory B cells of the infected individuals. Under certain conditions the virus can cause several human cancers, that include lymphoproliferative disorders such as Burkitt and Hodgkin lymphomas and non-lymphoid malignancies such as 100% of nasopharyngeal carcinoma and 10% of gastric cancers. Each year, about 200,000 EBV-related cancers emerge, hence accounting for at least 1% of worldwide cancers. Like all gammaherpesviruses, EBV has evolved a strategy to escape the host immune system. This strategy is mainly based on the tight control of the expression of its Epstein-Barr nuclear antigen-1 (EBNA1) protein, the EBV-encoded genome maintenance protein. Indeed, EBNA1 is essential for viral genome replication and maintenance but, at the same time, is also highly antigenic and T cells raised against EBNA1 exist in infected individuals. For this reason, EBNA1 is considered as the Achilles heel of EBV and the virus has seemingly evolved a strategy that employs the binding of nucleolin, a host cell factor, to RNA G-quadruplex (rG4) within EBNA1 mRNA to limit its expression to the minimal level required for function while minimizing immune recognition. This review recapitulates in a historical way the knowledge accumulated on EBNA1 immune evasion and discusses how this rG4-dependent mechanism can be exploited as an intervention point to unveil EBV-related cancers to the immune system.
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Affiliation(s)
- Van-Trang Dinh
- Univ Brest; Inserm UMR1078; Etablissement Français Du Sang (EFS) Bretagne; CHRU Brest, Hôpital Morvan, Laboratoire de Génétique Moléculaire, 22 Avenue Camille Desmoulins, F-29200 Brest, France.
| | - Nadège Loaëc
- Univ Brest; Inserm UMR1078; Etablissement Français Du Sang (EFS) Bretagne; CHRU Brest, Hôpital Morvan, Laboratoire de Génétique Moléculaire, 22 Avenue Camille Desmoulins, F-29200 Brest, France
| | - Alicia Quillévéré
- Univ Brest; Inserm UMR1078; Etablissement Français Du Sang (EFS) Bretagne; CHRU Brest, Hôpital Morvan, Laboratoire de Génétique Moléculaire, 22 Avenue Camille Desmoulins, F-29200 Brest, France
| | - Ronan Le Sénéchal
- Univ Brest; Inserm UMR1078; Etablissement Français Du Sang (EFS) Bretagne; CHRU Brest, Hôpital Morvan, Laboratoire de Génétique Moléculaire, 22 Avenue Camille Desmoulins, F-29200 Brest, France
| | - Marc Keruzoré
- Univ Brest; Inserm UMR1078; Etablissement Français Du Sang (EFS) Bretagne; CHRU Brest, Hôpital Morvan, Laboratoire de Génétique Moléculaire, 22 Avenue Camille Desmoulins, F-29200 Brest, France
| | | | - Anton Granzhan
- Chemistry and Modelling for the Biology of Cancer (CMBC), CNRS UMR9187, Inserm U1196, Institut Curie, Université Paris Saclay, F-91405 Orsay, France
| | - Marc Blondel
- Univ Brest; Inserm UMR1078; Etablissement Français Du Sang (EFS) Bretagne; CHRU Brest, Hôpital Morvan, Laboratoire de Génétique Moléculaire, 22 Avenue Camille Desmoulins, F-29200 Brest, France.
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2
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Fusée L, Salomao N, Ponnuswamy A, Wang L, López I, Chen S, Gu X, Polyzoidis S, Vadivel Gnanasundram S, Fahraeus R. The p53 endoplasmic reticulum stress-response pathway evolved in humans but not in mice via PERK-regulated p53 mRNA structures. Cell Death Differ 2023; 30:1072-1081. [PMID: 36813920 PMCID: PMC10070458 DOI: 10.1038/s41418-023-01127-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2022] [Revised: 01/27/2023] [Accepted: 02/01/2023] [Indexed: 02/24/2023] Open
Abstract
Cellular stress conditions activate p53-dependent pathways to counteract the inflicted damage. To achieve the required functional diversity, p53 is subjected to numerous post-translational modifications and the expression of isoforms. Little is yet known how p53 has evolved to respond to different stress pathways. The p53 isoform p53/47 (p47 or ΔNp53) is linked to aging and neural degeneration and is expressed in human cells via an alternative cap-independent translation initiation from the 2nd in-frame AUG at codon 40 (+118) during endoplasmic reticulum (ER) stress. Despite an AUG codon in the same location, the mouse p53 mRNA does not express the corresponding isoform in either human or mouse-derived cells. High-throughput in-cell RNA structure probing shows that p47 expression is attributed to PERK kinase-dependent structural alterations in the human p53 mRNA, independently of eIF2α. These structural changes do not take place in murine p53 mRNA. Surprisingly, PERK response elements required for the p47 expression are located downstream of the 2nd AUG. The data show that the human p53 mRNA has evolved to respond to PERK-mediated regulation of mRNA structures in order to control p47 expression. The findings highlight how p53 mRNA co-evolved with the function of the encoded protein to specify p53-activities under different cellular conditions.
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Affiliation(s)
- Leila Fusée
- Inserm U1131, 27 Rue Juliette Dodu, 75010, Paris, France
| | - Norman Salomao
- Inserm U1131, 27 Rue Juliette Dodu, 75010, Paris, France
| | | | - Lixiao Wang
- Department of Medical Biosciences, Umea University, 90185, Umea, Sweden
| | - Ignacio López
- Biochemistry-Molecular Biology, Faculty of Science, Universidad de la República, Iguá 4225, 11400, Montevideo, Uruguay
| | - Sa Chen
- Department of Medical Biosciences, Umea University, 90185, Umea, Sweden
| | - Xiaolian Gu
- Department of Medical Biosciences, Umea University, 90185, Umea, Sweden
| | - Stavros Polyzoidis
- Department of Neurosurgery, AHEPA Hospital, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | | | - Robin Fahraeus
- Inserm U1131, 27 Rue Juliette Dodu, 75010, Paris, France. .,Department of Medical Biosciences, Umea University, 90185, Umea, Sweden. .,RECAMO, Masaryk Memorial Cancer Institute, Zluty kopec 7, 65653, Brno, Czech Republic.
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3
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Li M, Xu W, Zhang L, Gao E, Han X, Chen Z. Convallatoxin Inhibits Cell Proliferation and Induces Cell Apoptosis by Attenuating the Akt-E2F1 Signaling Pathway in K562 Cells. Nat Prod Commun 2022. [DOI: 10.1177/1934578x221136929] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Objective: To determine the effect of convallatoxin on K562 cell proliferation and apoptosis. Methods: CCK-8 assay was used to detect cell proliferation; PI staining, JC-1 staining, and Annexin V-FITC/PI double staining were used to analyze the cell cycle, cell mitochondrial membrane potential, and cell apoptosis; and Western blotting was used to detect cleaved caspase-9, cleaved caspase-3, Bcl-2, Bax, and E2F1 expression and Akt phosphorylation. Subsequently, AutoDock software was used to determine the interaction between convallatoxin and Akt1. Results: Upon treatment with convallatoxin, the proliferation of K562 cells was inhibited, the cells were arrested at the S and G2/M phases, and cell apoptosis was significantly induced. In addition, Akt phosphorylation and E2F1 expression were significantly decreased, whereas E2F1 overexpression rescued convallatoxin-induced cell proliferation and apoptosis. In addition, a molecular docking assay indicated that convallatoxin could bind to Akt1. Conclusion: Convallatoxin inhibited cell proliferation and induced mitochondrial-related apoptosis in K562 cells by reducing the Akt-E2F1 signaling pathway, indicating that it is a potential agent for treating leukemia.
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Affiliation(s)
- Man Li
- Department of Clinical Laboratory, The Second People's Hospital of Hefei, Hefei, China
| | - Wangwang Xu
- Anhui Province Key Laboratory of Translational Cancer Research, Bengbu Medical College, Bengbu, China
| | - Lu Zhang
- Anhui Province Key Laboratory of Translational Cancer Research, Bengbu Medical College, Bengbu, China
| | - Erke Gao
- Anhui Province Key Laboratory of Translational Cancer Research, Bengbu Medical College, Bengbu, China
| | - Xiaojin Han
- Anhui Province Key Laboratory of Translational Cancer Research, Bengbu Medical College, Bengbu, China
| | - Zhengxu Chen
- Department of Clinical Laboratory, The Second People's Hospital of Hefei, Hefei, China
- Anhui Province Key Laboratory of Translational Cancer Research, Bengbu Medical College, Bengbu, China
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4
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Temaj G, Saha S, Dragusha S, Ejupi V, Buttari B, Profumo E, Beqa L, Saso L. Ribosomopathies and cancer: pharmacological implications. Expert Rev Clin Pharmacol 2022; 15:729-746. [PMID: 35787725 DOI: 10.1080/17512433.2022.2098110] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
INTRODUCTION The ribosome is a ribonucleoprotein organelle responsible for protein synthesis, and its biogenesis is a highly coordinated process that involves many macromolecular components. Any acquired or inherited impairment in ribosome biogenesis or ribosomopathies is associated with the development of different cancers and rare genetic diseases. Interference with multiple steps of protein synthesis has been shown to promote tumor cell death. AREAS COVERED We discuss the current insights about impaired ribosome biogenesis and their secondary consequences on protein synthesis, transcriptional and translational responses, proteotoxic stress, and other metabolic pathways associated with cancer and rare diseases. Studies investigating the modulation of different therapeutic chemical entities targeting cancer in in vitro and in vivo models have also been detailed. EXPERT OPINION Despite the association between inherited mutations affecting ribosome biogenesis and cancer biology, the development of therapeutics targeting the essential cellular machinery has only started to emerge. New chemical entities should be designed to modulate different checkpoints (translating oncoproteins, dysregulation of specific ribosome-assembly machinery, ribosomal stress, and rewiring ribosomal functions). Although safe and effective therapies are lacking, consideration should also be given to using existing drugs alone or in combination for long-term safety, with known risks for feasibility in clinical trials and synergistic effects.
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Affiliation(s)
| | - Sarmistha Saha
- Department of Cardiovascular, Endocrine-metabolic Diseases, and Aging, Italian National Institute of Health, Rome, Italy
| | | | - Valon Ejupi
- College UBT, Faculty of Pharmacy, Prishtina, Kosovo
| | - Brigitta Buttari
- Department of Cardiovascular, Endocrine-metabolic Diseases, and Aging, Italian National Institute of Health, Rome, Italy
| | - Elisabetta Profumo
- Department of Cardiovascular, Endocrine-metabolic Diseases, and Aging, Italian National Institute of Health, Rome, Italy
| | - Lule Beqa
- College UBT, Faculty of Pharmacy, Prishtina, Kosovo
| | - Luciano Saso
- Department of Physiology and Pharmacology "Vittorio Erspamer", Sapienza University of Rome, Italy
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5
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Song H, Zhang Y, Liu J, Liu W, Luo B. Activation of DNA methyltransferase 3a by Epstein-Barr nuclear antigen 1 in gastric carcinoma. Dig Liver Dis 2022; 54:973-983. [PMID: 34215536 DOI: 10.1016/j.dld.2021.06.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/12/2021] [Revised: 06/04/2021] [Accepted: 06/07/2021] [Indexed: 12/12/2022]
Abstract
BACKGROUND Epstein-Barr nuclear antigen 1 (EBNA1) is expressed in all Epstein-Barr virus (EBV)-infected cells. It interacts with a variety of cellular proteins and activates the transcription of other EBV latency genes, which plays an important role in the persistence of the EBV genome during latent infection. AIM Several studies have shown that EBV infection induces the expression of DNA methyltransferases (DNMTs) and causes extensive methylation of the whole genome in EBV-associated gastric carcinoma (EBVaGC). However, the specific mechanism by which EBV regulates DNMTs expression is still unclear. METHODS AND RESULTS EBNA1 plasmid and siRNA were transfected to evaluate the effect of EBNA1 on DNMT3a expression. Molecular biology experiments were used to detect the biological function of DNMT3a and its effect on EBV latency in gastric carcinoma cells. We showed that EBNA1 upregulated DNMT3a expression through the E2F1 transcription factor (E2F1) in EBVaGC. DNMT3a knockdown restrained cell proliferation, induced cell cycle arrest, promoted cell apoptosis and suppressed cell migration in vitro. CONCLUSIONS Our results showed a new mechanism for EBV to regulate the expression of DNMT3a. Targeting the EBNA1/E2F1/DNMT3a axis may provide an alternative therapeutic strategy in the treatment of EBVaGC with high DNMT3a expression.
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Affiliation(s)
- Hui Song
- Department of Pathogenic Biology, School of Basic Medicine, Qingdao University, No. 308 Ningxia Road, Qingdao 266071, China
| | - Yan Zhang
- Department of Pathogenic Biology, School of Basic Medicine, Qingdao University, No. 308 Ningxia Road, Qingdao 266071, China; Department of Clinical Laboratory, Zibo Central Hospital, 54 Gongqingtuan Road, Zibo 255036, China
| | - Juanjuan Liu
- Department of Pathogenic Biology, School of Basic Medicine, Qingdao University, No. 308 Ningxia Road, Qingdao 266071, China
| | - Wen Liu
- Department of Pathogenic Biology, School of Basic Medicine, Qingdao University, No. 308 Ningxia Road, Qingdao 266071, China.
| | - Bing Luo
- Department of Pathogenic Biology, School of Basic Medicine, Qingdao University, No. 308 Ningxia Road, Qingdao 266071, China.
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6
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Zheng AJL, Thermou A, Guixens Gallardo P, Malbert-Colas L, Daskalogianni C, Vaudiau N, Brohagen P, Granzhan A, Blondel M, Teulade-Fichou MP, Martins RP, Fahraeus R. The different activities of RNA G-quadruplex structures are controlled by flanking sequences. Life Sci Alliance 2021; 5:5/2/e202101232. [PMID: 34785537 PMCID: PMC8605322 DOI: 10.26508/lsa.202101232] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2021] [Revised: 11/08/2021] [Accepted: 11/08/2021] [Indexed: 12/17/2022] Open
Abstract
The role of G-quadruplex (G4) RNA structures is multifaceted and controversial. Here, we have used as a model the EBV-encoded EBNA1 and the Kaposi's sarcoma-associated herpesvirus (KSHV)-encoded LANA1 mRNAs. We have compared the G4s in these two messages in terms of nucleolin binding, nuclear mRNA retention, and mRNA translation inhibition and their effects on immune evasion. The G4s in the EBNA1 message are clustered in one repeat sequence and the G4 ligand PhenDH2 prevents all G4-associated activities. The RNA G4s in the LANA1 message take part in similar multiple mRNA functions but are spread throughout the message. The different G4 activities depend on flanking coding and non-coding sequences and, interestingly, can be separated individually. Together, the results illustrate the multifunctional, dynamic and context-dependent nature of G4 RNAs and highlight the possibility to develop ligands targeting specific RNA G4 functions. The data also suggest a common multifunctional repertoire of viral G4 RNA activities for immune evasion.
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Affiliation(s)
- Alice J-L Zheng
- Inserm UMRS1131, Institut de Génétique Moléculaire, Université Paris 7, Hôpital St. Louis, Paris, France
| | - Aikaterini Thermou
- Inserm UMRS1131, Institut de Génétique Moléculaire, Université Paris 7, Hôpital St. Louis, Paris, France.,ICCVS, University of Gdańsk, Science, Gdańsk, Poland
| | - Pedro Guixens Gallardo
- CNRS UMR9187, INSERM U1196, Institut Curie, PSL Research University, Orsay, France.,CNRS UMR9187, INSERM U1196, Université Paris Sud, Université Paris-Saclay, Orsay, France
| | - Laurence Malbert-Colas
- Inserm UMRS1131, Institut de Génétique Moléculaire, Université Paris 7, Hôpital St. Louis, Paris, France
| | - Chrysoula Daskalogianni
- Inserm UMRS1131, Institut de Génétique Moléculaire, Université Paris 7, Hôpital St. Louis, Paris, France.,ICCVS, University of Gdańsk, Science, Gdańsk, Poland
| | - Nathan Vaudiau
- Inserm UMRS1131, Institut de Génétique Moléculaire, Université Paris 7, Hôpital St. Louis, Paris, France
| | - Petter Brohagen
- Inserm UMRS1131, Institut de Génétique Moléculaire, Université Paris 7, Hôpital St. Louis, Paris, France
| | - Anton Granzhan
- CNRS UMR9187, INSERM U1196, Institut Curie, PSL Research University, Orsay, France.,CNRS UMR9187, INSERM U1196, Université Paris Sud, Université Paris-Saclay, Orsay, France
| | - Marc Blondel
- Inserm UMR1078, Université de Bretagne Occidentale (UBO), Etablissement Français du Sang (EFS) Bretagne, CHRU Brest, Brest, France
| | - Marie-Paule Teulade-Fichou
- CNRS UMR9187, INSERM U1196, Institut Curie, PSL Research University, Orsay, France.,CNRS UMR9187, INSERM U1196, Université Paris Sud, Université Paris-Saclay, Orsay, France
| | | | - Robin Fahraeus
- Inserm UMRS1131, Institut de Génétique Moléculaire, Université Paris 7, Hôpital St. Louis, Paris, France .,RECAMO, Masaryk Memorial Cancer Institute, Brno, Czech Republic.,Department of Medical Biosciences, Umeå University, Umeå, Sweden.,ICCVS, University of Gdańsk, Science, Gdańsk, Poland
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7
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The Epstein-Barr virus noncoding RNA EBER2 transactivates the UCHL1 deubiquitinase to accelerate cell growth. Proc Natl Acad Sci U S A 2021; 118:2115508118. [PMID: 34686609 DOI: 10.1073/pnas.2115508118] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/08/2021] [Indexed: 12/23/2022] Open
Abstract
The Epstein-Barr virus (EBV) transforms resting B cells and is involved in the development of B cell lymphomas. We report here that the viral noncoding RNA EBER2 accelerates B cell growth by potentiating expression of the UCHL1 deubiquitinase that itself increased expression of the Aurora kinases and of cyclin B1. Importantly, this effect was also visible in Burkitt's lymphoma cells that express none of the virus's known oncogenes. Mechanistically, EBER2 bound the UCHL1 messenger RNA (mRNA), thereby bringing a protein complex that includes PU.1, a UCHL1 transactivator, to the vicinity of its promoter. Although the EBV oncogene LMP1 has been suggested to induce UCHL1, we show here that EBER2 plays a much more important role to reach significant levels of the deubiquitinase in infected cells. However, some viruses that carried a polymorphic LMP1 had an increased ability to achieve full UCHL1 expression. This work identifies a direct cellular target of a viral noncoding RNA that is likely to be central to EBV's oncogenic properties.
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8
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Vadivel Gnanasundram S, Bonczek O, Wang L, Chen S, Fahraeus R. p53 mRNA Metabolism Links with the DNA Damage Response. Genes (Basel) 2021; 12:genes12091446. [PMID: 34573428 PMCID: PMC8465283 DOI: 10.3390/genes12091446] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2021] [Revised: 09/10/2021] [Accepted: 09/13/2021] [Indexed: 12/14/2022] Open
Abstract
Human cells are subjected to continuous challenges by different genotoxic stress attacks. DNA damage leads to erroneous mutations, which can alter the function of oncogenes or tumor suppressors, resulting in cancer development. To circumvent this, cells activate the DNA damage response (DDR), which mainly involves cell cycle regulation and DNA repair processes. The tumor suppressor p53 plays a pivotal role in the DDR by halting the cell cycle and facilitating the DNA repair processes. Various pathways and factors participating in the detection and repair of DNA have been described, including scores of RNA-binding proteins (RBPs) and RNAs. It has become increasingly clear that p53’s role is multitasking, and p53 mRNA regulation plays a prominent part in the DDR. This review is aimed at covering the p53 RNA metabolism linked to the DDR and highlights the recent findings.
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Affiliation(s)
- Sivakumar Vadivel Gnanasundram
- Department of Medical Biosciences, Umeå University, 901-87 Umeå, Sweden; (O.B.); (L.W.); (S.C.)
- Correspondence: (S.V.G.); (R.F.)
| | - Ondrej Bonczek
- Department of Medical Biosciences, Umeå University, 901-87 Umeå, Sweden; (O.B.); (L.W.); (S.C.)
- RECAMO, Masaryk Memorial Cancer Institute, Zluty Kopec 7, 656-53 Brno, Czech Republic
| | - Lixiao Wang
- Department of Medical Biosciences, Umeå University, 901-87 Umeå, Sweden; (O.B.); (L.W.); (S.C.)
| | - Sa Chen
- Department of Medical Biosciences, Umeå University, 901-87 Umeå, Sweden; (O.B.); (L.W.); (S.C.)
| | - Robin Fahraeus
- Department of Medical Biosciences, Umeå University, 901-87 Umeå, Sweden; (O.B.); (L.W.); (S.C.)
- RECAMO, Masaryk Memorial Cancer Institute, Zluty Kopec 7, 656-53 Brno, Czech Republic
- Inserm UMRS1131, Institut de Genetique Moleculaire, Universite Paris 7, Hopital St Louis, F-75010 Paris, France
- International Centre for Cancer Vaccine Science, University of Gdansk, 80-822 Gdansk, Poland
- Correspondence: (S.V.G.); (R.F.)
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9
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Padariya M, Kalathiya U, Mikac S, Dziubek K, Tovar Fernandez MC, Sroka E, Fahraeus R, Sznarkowska A. Viruses, cancer and non-self recognition. Open Biol 2021; 11:200348. [PMID: 33784856 PMCID: PMC8061760 DOI: 10.1098/rsob.200348] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2020] [Accepted: 03/04/2021] [Indexed: 12/11/2022] Open
Abstract
Virus-host interactions form an essential part of every aspect of life, and this review is aimed at looking at the balance between the host and persistent viruses with a focus on the immune system. The virus-host interaction is like a cat-and-mouse game and viruses have developed ingenious mechanisms to manipulate cellular pathways, most notably the major histocompatibility (MHC) class I pathway, to reside within infected cell while evading detection and destruction by the immune system. However, some of the signals sensing and responding to viral infection are derived from viruses and the fact that certain viruses can prevent the infection of others, highlights a more complex coexistence between the host and the viral microbiota. Viral immune evasion strategies also illustrate that processes whereby cells detect and present non-self genetic material to the immune system are interlinked with other cellular pathways. Immune evasion is a target also for cancer cells and a more detailed look at the interfaces between viral factors and components of the MHC class I peptide-loading complex indicates that these interfaces are also targets for cancer mutations. In terms of the immune checkpoint, however, viral and cancer strategies appear different.
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Affiliation(s)
- Monikaben Padariya
- International Centre for Cancer Vaccine Science, University of Gdansk, Kladki 24, 80-822 Gdansk, Poland
| | - Umesh Kalathiya
- International Centre for Cancer Vaccine Science, University of Gdansk, Kladki 24, 80-822 Gdansk, Poland
| | - Sara Mikac
- International Centre for Cancer Vaccine Science, University of Gdansk, Kladki 24, 80-822 Gdansk, Poland
| | - Katarzyna Dziubek
- International Centre for Cancer Vaccine Science, University of Gdansk, Kladki 24, 80-822 Gdansk, Poland
| | - Maria C. Tovar Fernandez
- International Centre for Cancer Vaccine Science, University of Gdansk, Kladki 24, 80-822 Gdansk, Poland
| | - Ewa Sroka
- International Centre for Cancer Vaccine Science, University of Gdansk, Kladki 24, 80-822 Gdansk, Poland
| | - Robin Fahraeus
- International Centre for Cancer Vaccine Science, University of Gdansk, Kladki 24, 80-822 Gdansk, Poland
- Inserm UMRS1131, Institut de Génétique Moléculaire, Université Paris 7, Hôpital St. Louis, F-75010 Paris, France
- RECAMO, Masaryk Memorial Cancer Institute, Zluty kopec 7, 65653 Brno, Czech Republic
- Department of Medical Biosciences, Umeå University, Building 6M, 901 85 Umeå, Sweden
| | - Alicja Sznarkowska
- International Centre for Cancer Vaccine Science, University of Gdansk, Kladki 24, 80-822 Gdansk, Poland
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10
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Shindiapina P, Ahmed EH, Mozhenkova A, Abebe T, Baiocchi RA. Immunology of EBV-Related Lymphoproliferative Disease in HIV-Positive Individuals. Front Oncol 2020; 10:1723. [PMID: 33102204 PMCID: PMC7556212 DOI: 10.3389/fonc.2020.01723] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2020] [Accepted: 08/03/2020] [Indexed: 12/11/2022] Open
Abstract
Epstein-Bar virus (EBV) can directly cause lymphoproliferative disease (LPD), including AIDS-defining lymphomas such as Burkitt’s lymphoma and other non-Hodgkin lymphomas (NHL), as well as human immunodeficiency virus (HIV)-related Hodgkin lymphoma (HL). The prevalence of EBV in HL and NHL is elevated in HIV-positive individuals compared with the general population. Rates of incidence of AIDS-defining cancers have been declining in HIV-infected individuals since initiation of combination anti-retroviral therapy (cART) use in 1996. However, HIV-infected persons remain at an increased risk of cancers related to infections with oncogenic viruses. Proposed pathogenic mechanisms of HIV-related cancers include decreased immune surveillance, decreased ability to suppress infection-related oncogenic processes and a state of chronic inflammation marked by alteration of the cytokine profile and expanded numbers of cytotoxic T lymphocytes with down-regulated co-stimulatory molecules and increased expression of markers of senescence in the setting of treated HIV infection. Here we discuss the cooperation of EBV-infected B cell- and environment-associated factors that may contribute to EBV-related lymphomagenesis in HIV-infected individuals. Environment-derived lymphomagenic factors include impaired host adaptive and innate immune surveillance, cytokine dysregulation and a pro-inflammatory state observed in the setting of chronic, cART-treated HIV infection. B cell factors include distinctive EBV latency patterns and host protein expression in HIV-associated LPD, as well as B cell-stimulating factors derived from HIV infection. We review the future directions for expanding therapeutic approaches in targeting the viral and immune components of EBV LPD pathogenesis.
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Affiliation(s)
- Polina Shindiapina
- Division of Hematology, Department of Internal Medicine, The Ohio State University, Columbus, OH, United States.,Comprehensive Cancer Center, The James Cancer Hospital and Solove Research Institute, The Ohio State University, Columbus, OH, United States
| | - Elshafa H Ahmed
- Comprehensive Cancer Center, The James Cancer Hospital and Solove Research Institute, The Ohio State University, Columbus, OH, United States
| | - Anna Mozhenkova
- Comprehensive Cancer Center, The James Cancer Hospital and Solove Research Institute, The Ohio State University, Columbus, OH, United States
| | - Tamrat Abebe
- Department of Microbiology, Immunology, and Parasitology, School of Medicine Tikur Anbessa Specialized Hospital, College of Health Sciences, Addis Ababa University, Addis Ababa, Ethiopia
| | - Robert A Baiocchi
- Division of Hematology, Department of Internal Medicine, The Ohio State University, Columbus, OH, United States.,Comprehensive Cancer Center, The James Cancer Hospital and Solove Research Institute, The Ohio State University, Columbus, OH, United States
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11
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Gnanasundram SV, Malbert-Colas L, Chen S, Fusée L, Daskalogianni C, Muller P, Salomao N, Fåhraeus R. MDM2's dual mRNA binding domains co-ordinate its oncogenic and tumour suppressor activities. Nucleic Acids Res 2020; 48:6775-6787. [PMID: 32453417 PMCID: PMC7337897 DOI: 10.1093/nar/gkaa431] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2020] [Revised: 05/05/2020] [Accepted: 05/11/2020] [Indexed: 12/16/2022] Open
Abstract
Cell growth requires a high level of protein synthesis and oncogenic pathways stimulate cell proliferation and ribosome biogenesis. Less is known about how cells respond to dysfunctional mRNA translation and how this feeds back into growth regulatory pathways. The Epstein-Barr virus (EBV)-encoded EBNA1 causes mRNA translation stress in cis that activates PI3Kδ. This leads to the stabilization of MDM2, induces MDM2's binding to the E2F1 mRNA and promotes E2F1 translation. The MDM2 serine 166 regulates the interaction with the E2F1 mRNA and deletion of MDM2 C-terminal RING domain results in a constitutive E2F1 mRNA binding. Phosphorylation on serine 395 following DNA damage instead regulates p53 mRNA binding to its RING domain and prevents the E2F1 mRNA interaction. The p14Arf tumour suppressor binds MDM2 and in addition to preventing degradation of the p53 protein it also prevents the E2F1 mRNA interaction. The data illustrate how two MDM2 domains selectively bind specific mRNAs in response to cellular conditions to promote, or suppress, cell growth and how p14Arf coordinates MDM2's activity towards p53 and E2F1. The data also show how EBV via EBNA1-induced mRNA translation stress targets the E2F1 and the MDM2 - p53 pathway.
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Affiliation(s)
| | - Laurence Malbert-Colas
- Inserm UMRS1131, Institut de Génétique Moléculaire, Université Paris 7, Hôpital St. Louis, F-75010 Paris, France
| | - Sa Chen
- Department of Medical Biosciences, Building 6M, Umeå University, 901 85 Umeå, Sweden
| | - Leila Fusée
- Inserm UMRS1131, Institut de Génétique Moléculaire, Université Paris 7, Hôpital St. Louis, F-75010 Paris, France
| | - Chrysoula Daskalogianni
- Inserm UMRS1131, Institut de Génétique Moléculaire, Université Paris 7, Hôpital St. Louis, F-75010 Paris, France
| | - Petr Muller
- RECAMO, Masaryk Memorial Cancer Institute, Zlutykopec 7, 65653 Brno, Czech Republic
| | - Norman Salomao
- Inserm UMRS1131, Institut de Génétique Moléculaire, Université Paris 7, Hôpital St. Louis, F-75010 Paris, France
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12
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Han H, Chen N, Huang X, Liu B, Tian J, Lei H. Phosphoinositide 3-kinase δ inactivation prevents vitreous-induced activation of AKT/MDM2/p53 and migration of retinal pigment epithelial cells. J Biol Chem 2019; 294:15408-15417. [PMID: 31467081 DOI: 10.1074/jbc.ra119.010130] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2019] [Revised: 08/22/2019] [Indexed: 12/15/2022] Open
Abstract
Phosphoinositide 3-kinases (PI3Ks) are a family of lipid kinases that play a critical role in transmitting signals from cell-surface molecules to intracellular protein effectors. Key PI3Ks include PI3Kα, PI3Kβ, and PI3Kδ, which are regulated by receptors. The signaling pathway comprising the PI3Ks, along with a Ser/Thr kinase (AKT), a proto-oncogene product (mouse double minute (MDM)2), and a tumor suppressor protein (p53), plays an essential role in experimental proliferative vitreoretinopathy (PVR), which is a fibrotic blinding eye disorder. However, which PI3K isoforms are involved in PVR is unknown. A major characteristic of PVR is the formation of epi (or sub)-retinal membranes that consist of extracellular matrix and cells, including retinal pigment epithelium (RPE) cells, glial cells, and macrophages. RPE cells are considered key players in PVR pathogenesis. Using immunoblotting and immunofluorescence analyses, we herein provide the evidence that PI3Kδ is highly expressed in human RPEs when it is primarily expressed in leukocytes. We also found that PI3Kδ inactivation through two approaches, CRISPR/Cas9-mediated depletion and a PI3Kδ-specific inhibitor (idelalisib), not only blocks vitreous-induced activation of AKT and MDM2 but also abrogates a vitreous-stimulated decrease in p53. Furthermore, we demonstrate that PI3Kδ inactivation prevents vitreous-induced proliferation, migration, and contraction of human RPEs. These results suggest that PI3Kδ may represent a potential therapeutic target for RPE-related eye diseases, including PVR.
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Affiliation(s)
- Haote Han
- Schepens Eye Research Institute of Massachusetts Eye and Ear, Boston, Massachusetts 02114.,Department of Ophthalmology, Harvard Medical School, Boston, Massachusetts 02115.,College of Biomedical Engineering and Instrument Science, Zhejiang University, Hangzhou 310027, China.,Zhejiang-Malaysia Joint Research Center for Traditional Medicine, Zhejiang University, Hangzhou 310027 China
| | - Na Chen
- Schepens Eye Research Institute of Massachusetts Eye and Ear, Boston, Massachusetts 02114.,Department of Ophthalmology, Harvard Medical School, Boston, Massachusetts 02115.,Department of Ophthalmology, Renji Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai 200127, China
| | - Xionggao Huang
- Schepens Eye Research Institute of Massachusetts Eye and Ear, Boston, Massachusetts 02114.,Department of Ophthalmology, Harvard Medical School, Boston, Massachusetts 02115.,Department of Ophthalmology, The First Affiliated Hospital of Hainan Medical University, Haikou 570102, China
| | - Bing Liu
- Schepens Eye Research Institute of Massachusetts Eye and Ear, Boston, Massachusetts 02114.,Department of Ophthalmology, Harvard Medical School, Boston, Massachusetts 02115
| | - Jingkui Tian
- College of Biomedical Engineering and Instrument Science, Zhejiang University, Hangzhou 310027, China.,Zhejiang-Malaysia Joint Research Center for Traditional Medicine, Zhejiang University, Hangzhou 310027 China
| | - Hetian Lei
- Schepens Eye Research Institute of Massachusetts Eye and Ear, Boston, Massachusetts 02114 .,Department of Ophthalmology, Harvard Medical School, Boston, Massachusetts 02115
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13
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Mechanisms of B-Cell Oncogenesis Induced by Epstein-Barr Virus. J Virol 2019; 93:JVI.00238-19. [PMID: 30971472 PMCID: PMC6580952 DOI: 10.1128/jvi.00238-19] [Citation(s) in RCA: 66] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2019] [Accepted: 04/08/2019] [Indexed: 12/12/2022] Open
Abstract
Epstein-Barr virus (EBV) is a ubiquitous gammaherpesvirus which asymptomatically infects the majority of the world population. Under immunocompromised conditions, EBV can trigger human cancers of epithelial and lymphoid origin. The oncogenic potential of EBV is demonstrated by in vitro infection and transformation of quiescent B cells into lymphoblastoid cell lines (LCLs). These cell lines, along with primary infection using genetically engineered viral particles coupled with recent technological advancements, have elucidated the underlying mechanisms of EBV-induced B-cell lymphomagenesis.
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14
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Martins RP, Malbert-Colas L, Lista MJ, Daskalogianni C, Apcher S, Pla M, Findakly S, Blondel M, Fåhraeus R. Nuclear processing of nascent transcripts determines synthesis of full-length proteins and antigenic peptides. Nucleic Acids Res 2019; 47:3086-3100. [PMID: 30624716 PMCID: PMC6451098 DOI: 10.1093/nar/gky1296] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2018] [Revised: 11/23/2018] [Accepted: 12/18/2018] [Indexed: 01/19/2023] Open
Abstract
Peptides presented on major histocompatibility (MHC) class I molecules form an essential part of the immune system's capacity to detect virus-infected or transformed cells. Earlier works have shown that pioneer translation peptides (PTPs) for the MHC class I pathway are as efficiently produced from introns as from exons, or from mRNAs targeted for the nonsense-mediated decay pathway. The production of PTPs is a target for viral immune evasion but the underlying molecular mechanisms that govern this non-canonical translation are unknown. Here, we have used different approaches to show how events taking place on the nascent transcript control the synthesis of PTPs and full-length proteins. By controlling the subcellular interaction between the G-quadruplex structure (G4) of a gly-ala encoding mRNA and nucleolin (NCL) and by interfering with mRNA maturation using multiple approaches, we demonstrate that antigenic peptides derive from a nuclear non-canonical translation event that is independently regulated from the synthesis of full-length proteins. Moreover, we show that G4 are exploited to control mRNA localization and translation by distinguishable mechanisms that are targets for viral immune evasion.
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Affiliation(s)
| | | | - María José Lista
- Université de Brest, Inserm, EFS, UMR 1078, GGB, F-29200 Brest, France
| | - Chrysoula Daskalogianni
- Université Paris 7, Inserm, UMR 1162, Paris, France
- ICCVS, University of Gdańsk, Science, ul. Wita Stwosza 63, 80-308 Gdańsk, Poland
| | - Sebastien Apcher
- Institut Gustave Roussy, Université Paris Sud, UMR 1015, Villejuif, France
| | - Marika Pla
- Université Paris 7, IUH, Inserm, UMR-S-1131, Paris, France
| | | | - Marc Blondel
- Université de Brest, Inserm, EFS, UMR 1078, GGB, F-29200 Brest, France
| | - Robin Fåhraeus
- Université Paris 7, Inserm, UMR 1162, Paris, France
- ICCVS, University of Gdańsk, Science, ul. Wita Stwosza 63, 80-308 Gdańsk, Poland
- Department of Medical Biosciences, Umeå University, Umeå, Sweden
- RECAMO, Masaryk Memorial Cancer Institute, Zluty kopec 7, 656 53 Brno, Czech Republic
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15
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Abstract
Epstein–Barr virus (EBV) contributes to about 1.5% of all cases of human cancer worldwide, and viral genes are expressed in the malignant cells. EBV also very efficiently causes the proliferation of infected human B lymphocytes. The functions of the viral proteins and small RNAs that may contribute to EBV-associated cancers are becoming increasingly clear, and a broader understanding of the sequence variation of the virus genome has helped to interpret their roles. The improved understanding of the mechanisms of these cancers means that there are great opportunities for the early diagnosis of treatable stages of EBV-associated cancers and the use of immunotherapy to target EBV-infected cells or overcome immune evasion. There is also scope for preventing disease by immunization and for developing therapeutic agents that target the EBV gene products expressed in the cancers.
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Affiliation(s)
- Paul J. Farrell
- Section of Virology, Imperial College Faculty of Medicine, London W2 1PG, United Kingdom
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16
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Pyndiah S. [Stressed ribosomes, a new pathway to promote oncogenesis used by EBNA1]. Med Sci (Paris) 2018; 34:907-909. [PMID: 30526827 DOI: 10.1051/medsci/2018228] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Slovénie Pyndiah
- Inserm UMRS1162, équipe labellisée la ligue contre le cancer, institut de génétique moléculaire, université Paris 7, hôpital Saint Louis, 75010 Paris, France
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17
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Vadivel Gnanasundram S, Fåhraeus R. Translation Stress Regulates Ribosome Synthesis and Cell Proliferation. Int J Mol Sci 2018; 19:ijms19123757. [PMID: 30486342 PMCID: PMC6321632 DOI: 10.3390/ijms19123757] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2018] [Revised: 11/23/2018] [Accepted: 11/24/2018] [Indexed: 12/11/2022] Open
Abstract
Ribosome and protein synthesis are major metabolic events that control cellular growth and proliferation. Impairment in ribosome biogenesis pathways and mRNA translation is associated with pathologies such as cancer and developmental disorders. Processes that control global protein synthesis are tightly regulated at different levels by numerous factors and linked with multiple cellular signaling pathways. Several of these merge on the growth promoting factor c-Myc, which induces ribosome biogenesis by stimulating Pol I, Pol II, and Pol III transcription. However, how cells sense and respond to mRNA translation stress is not well understood. It was more recently shown that mRNA translation stress activates c-Myc, through a specific induction of E2F1 synthesis via a PI3Kδ-dependent pathway. This review focuses on how this novel feedback pathway stimulates cellular growth and proliferation pathways to synchronize protein synthesis with ribosome biogenesis. It also describes for the first time the oncogenic activity of the mRNA, and not the encoded protein.
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Affiliation(s)
| | - Robin Fåhraeus
- Inserm UMRS1162, Institut de Génétique Moléculaire, Université Paris 7, Hôpital St. Louis, F-75010 Paris, France.
- RECAMO, Masaryk Memorial Cancer Institute, Zluty kopec 7, 65653 Brno, Czech Republic.
- Department of Medical Biosciences, Building 6M, Umeå University, 901 85 Umeå, Sweden.
- ICCVS, University of Gdańsk, Science, ul. Wita Stwosza 63, 80-308 Gdańsk, Poland.
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18
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Lymphomas driven by Epstein-Barr virus nuclear antigen-1 (EBNA1) are dependant upon Mdm2. Oncogene 2018; 37:3998-4012. [PMID: 29691476 PMCID: PMC6054874 DOI: 10.1038/s41388-018-0147-x] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2017] [Revised: 12/07/2017] [Accepted: 12/19/2017] [Indexed: 12/22/2022]
Abstract
Epstein-Barr virus (EBV) associated Burkitt’s lymphoma is characterised by the deregulation of c-Myc expression and a restricted viral gene expression pattern in which the EBV nuclear antigen-1 (EBNA1) is the only viral protein to be consistently expressed. EBNA1 is required for viral genome propagation and segregation during latency. However, it has been much debated whether the protein plays a role in viral-associated tumourigenesis. We show that the lymphomas which arise in EµEBNA1 transgenic mice are unequivocally linked to EBNA1 expression and that both C-Myc and Mdm2 deregulation are central to this process. Tumour cell survival is supported by IL-2 and there is a skew towards CD8 positive T-cells in the tumour environment, while the immune check-point protein PD-L1 is upregulated in the tumours. Additionally, several isoforms of Mdm2 are upregulated in the EµEBNA1 tumours, with increased phosphorylation at ser166, an expression pattern not seen in Eµc-Myc transgenic tumours. Concomitantly, E2F1, Xiap, Mta1, C-Fos and Stat1 are upregulated in the tumours. Using four independent inhibitors of Mdm2 we demonstrate that the EµEBNA1 tumour cells are dependant upon Mdm2 for survival (as they are upon c-Myc) and that Mdm2 inhibition is not accompanied by upregulation of p53, instead cell death is linked to loss of E2F1 expression, providing new insight into the underlying tumourigenic mechanism. This opens a new path to combat EBV-associated disease.
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19
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EBNA1: Oncogenic Activity, Immune Evasion and Biochemical Functions Provide Targets for Novel Therapeutic Strategies against Epstein-Barr Virus- Associated Cancers. Cancers (Basel) 2018; 10:cancers10040109. [PMID: 29642420 PMCID: PMC5923364 DOI: 10.3390/cancers10040109] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2018] [Revised: 03/26/2018] [Accepted: 03/29/2018] [Indexed: 12/12/2022] Open
Abstract
The presence of the Epstein-Barr virus (EBV)-encoded nuclear antigen-1 (EBNA1) protein in all EBV-carrying tumours constitutes a marker that distinguishes the virus-associated cancer cells from normal cells and thereby offers opportunities for targeted therapeutic intervention. EBNA1 is essential for viral genome maintenance and also for controlling viral gene expression and without EBNA1, the virus cannot persist. EBNA1 itself has been linked to cell transformation but the underlying mechanism of its oncogenic activity has been unclear. However, recent data are starting to shed light on its growth-promoting pathways, suggesting that targeting EBNA1 can have a direct growth suppressing effect. In order to carry out its tasks, EBNA1 interacts with cellular factors and these interactions are potential therapeutic targets, where the aim would be to cripple the virus and thereby rid the tumour cells of any oncogenic activity related to the virus. Another strategy to target EBNA1 is to interfere with its expression. Controlling the rate of EBNA1 synthesis is critical for the virus to maintain a sufficient level to support viral functions, while at the same time, restricting expression is equally important to prevent the immune system from detecting and destroying EBNA1-positive cells. To achieve this balance EBNA1 has evolved a unique repeat sequence of glycines and alanines that controls its own rate of mRNA translation. As the underlying molecular mechanisms for how this repeat suppresses its own rate of synthesis in cis are starting to be better understood, new therapeutic strategies are emerging that aim to modulate the translation of the EBNA1 mRNA. If translation is induced, it could increase the amount of EBNA1-derived antigenic peptides that are presented to the major histocompatibility (MHC) class I pathway and thus, make EBV-carrying cancers better targets for the immune system. If translation is further suppressed, this would provide another means to cripple the virus.
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