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Fadaee A, Mohammadi FS, Ariaee N, Ahmadi Ghezeldasht S, Valizadeh N, Kheradmand F, Boostani R, Rafatpanah H, Rezaee SA. Cannabinoid receptors as new targets for HTLV-1 associated myelopathy (HAM/TSP) treatment. Mult Scler Relat Disord 2024; 87:105659. [PMID: 38704874 DOI: 10.1016/j.msard.2024.105659] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2023] [Revised: 04/16/2024] [Accepted: 04/27/2024] [Indexed: 05/07/2024]
Abstract
BACKGROUND/AIM The roles of endocannabinoids are described in immune modulation and neuroprotection. HTLV-1-associated myelopathy (HAM/TSP) is an inflammatory neurodegenerative disease. Therefore, in this study, the interactions of HTLV-1 regulatory factors and host cannabinoid receptors (CBRs) were evaluated in HAM/TSP. METHODS Nineteen HAM/TSPs, 22 asymptomatic carriers (ACs), and 18 healthy controls (HCs) were enrolled. RNA was extracted from PBMCs and then reverse-transcribed to cDNA. The gene expression of CB1R and CB2R, as well as HTLV-1 proviral load (PVL), Tax and HTLV-1 basic leucine zipper factor (HBZ) were assessed by RT-qPCR. RESULTS The mean expression of CB1R in ACs (8.51 ± 2.76) was significantly higher than HAMTSPs (1.593 ± 0.74, p = 0.05) and also HCs (0.10 ± 0.039, p = 0.001). The CB2R gene expression level in ACs (2.62±0.44) was significantly higher than HAM/TSPs (0.59 ± 0.15, p = 0.001) and HCs (1.00 ± 0.2, p = 0.006). Meanwhile there was a strong correlation between CB1R and CB2R gene expression levels in the HCs and HAM/TSPs (p = 0.001). HTLV-1-Tax expression in HAM/TSPs (386 ± 104) was higher than ACs (75 ± 32) and statistically significant (p = 0.003). While HTLV-1-HBZ was only expressed in three AC subjects and five HAM/TSPs, thus it cannot be analyzed. CONCLUSION The up-regulation of CB2R has immunomodulatory effects in inflammatory reactions. While CB1R as a neuroprotective agent may suppress inflammatory reactions in ACs, preventing HAM/TSP. It seems that, like multiple sclerosis (MS), cannabinoid medications are beneficial in HAM/TSP.
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Affiliation(s)
- Afsane Fadaee
- Faculty of Medicine, Immunology Research Center, Inflammation and Inflammatory Diseases Division, Mashhad University of Medical Sciences, Azadi-Square, Medical Campus, Mashhad 9177948564, Iran; HTLV-1 Foundation, Ghaem Hospital, Mashhad University of Medical Sciences, Ahmad Abad Bolv., Mashhad, Iran
| | - Fatemeh Sadat Mohammadi
- Faculty of Medicine, Immunology Research Center, Inflammation and Inflammatory Diseases Division, Mashhad University of Medical Sciences, Azadi-Square, Medical Campus, Mashhad 9177948564, Iran
| | - Nazila Ariaee
- Faculty of Medicine, Immunology Research Center, Inflammation and Inflammatory Diseases Division, Mashhad University of Medical Sciences, Azadi-Square, Medical Campus, Mashhad 9177948564, Iran
| | - Sanaz Ahmadi Ghezeldasht
- Blood Borne Infections Research Center, Academic Center for Education, Culture, and Research (ACECR), Razavi Khorasan, Mashhad, Iran
| | - Narges Valizadeh
- Faculty of Medicine, Immunology Research Center, Inflammation and Inflammatory Diseases Division, Mashhad University of Medical Sciences, Azadi-Square, Medical Campus, Mashhad 9177948564, Iran
| | - Fatemeh Kheradmand
- Immunology Research Center, Department of Immunology, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Reza Boostani
- HTLV-1 Foundation, Ghaem Hospital, Mashhad University of Medical Sciences, Ahmad Abad Bolv., Mashhad, Iran
| | - Houshang Rafatpanah
- Faculty of Medicine, Immunology Research Center, Inflammation and Inflammatory Diseases Division, Mashhad University of Medical Sciences, Azadi-Square, Medical Campus, Mashhad 9177948564, Iran; HTLV-1 Foundation, Ghaem Hospital, Mashhad University of Medical Sciences, Ahmad Abad Bolv., Mashhad, Iran
| | - Seyed Abdolrahim Rezaee
- Faculty of Medicine, Immunology Research Center, Inflammation and Inflammatory Diseases Division, Mashhad University of Medical Sciences, Azadi-Square, Medical Campus, Mashhad 9177948564, Iran; HTLV-1 Foundation, Ghaem Hospital, Mashhad University of Medical Sciences, Ahmad Abad Bolv., Mashhad, Iran.
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Marino-Merlo F, Grelli S, Mastino A, Lai M, Ferrari P, Nicolini A, Pistello M, Macchi B. Human T-Cell Leukemia Virus Type 1 Oncogenesis between Active Expression and Latency: A Possible Source for the Development of Therapeutic Targets. Int J Mol Sci 2023; 24:14807. [PMID: 37834255 PMCID: PMC10572738 DOI: 10.3390/ijms241914807] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2023] [Revised: 09/16/2023] [Accepted: 09/28/2023] [Indexed: 10/15/2023] Open
Abstract
The human T-cell leukemia virus type 1 (HTLV-1) is the only known human oncogenic retrovirus. HTLV-1 can cause a type of cancer called adult T-cell leukemia/lymphoma (ATL). The virus is transmitted through the body fluids of infected individuals, primarily breast milk, blood, and semen. At least 5-10 million people in the world are infected with HTLV-1. In addition to ATL, HTLV-1 infection can also cause HTLV-I-associated myelopathy (HAM/TSP). ATL is characterized by a low viral expression and poor prognosis. The oncogenic mechanism triggered by HTLV-1 is extremely complex and the molecular pathways are not fully understood. However, viral regulatory proteins Tax and HTLV-1 bZIP factor (HBZ) have been shown to play key roles in the transformation of HTLV-1-infected T cells. Moreover, several studies have shown that the final fate of HTLV-1-infected transformed Tcell clones is the result of a complex interplay of HTLV-1 oncogenic protein expression with cellular transcription factors that subvert the cell cycle and disrupt regulated cell death, thereby exerting their transforming effects. This review provides updated information on the mechanisms underlying the transforming action of HTLV-1 and highlights potential therapeutic targets to combat ATL.
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Affiliation(s)
- Francesca Marino-Merlo
- Department of Chemical, Biological, Pharmaceutical and Environmental Sciences, University of Messina, 98166 Messina, Italy;
| | - Sandro Grelli
- Department of Experimental Medicine, University of Rome “Tor Vergata”, 00133 Rome, Italy;
| | - Antonio Mastino
- The Institute of Translational Pharmacology, CNR, 00133 Rome, Italy;
| | - Michele Lai
- Retrovirus Center and Virology Section, Department of Translational Research, University of Pisa, 56100 Pisa, Italy; (M.L.); (M.P.)
| | - Paola Ferrari
- Unit of Oncology, Department of Medical and Oncological Area, Azienda Ospedaliera—Universitaria Pisana, 56125 Pisa, Italy;
| | - Andrea Nicolini
- Department of Oncology, Transplantations and New Technologies in Medicine, University of Pisa, 56126 Pisa, Italy
| | - Mauro Pistello
- Retrovirus Center and Virology Section, Department of Translational Research, University of Pisa, 56100 Pisa, Italy; (M.L.); (M.P.)
| | - Beatrice Macchi
- Department of Chemical Science and Technology, University of Rome “Tor Vergata”, 00133 Rome, Italy;
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Mohanty S, Harhaj EW. Mechanisms of Innate Immune Sensing of HTLV-1 and Viral Immune Evasion. Pathogens 2023; 12:pathogens12050735. [PMID: 37242405 DOI: 10.3390/pathogens12050735] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2023] [Revised: 05/15/2023] [Accepted: 05/18/2023] [Indexed: 05/28/2023] Open
Abstract
Human T lymphotropic virus-1 (HTLV-1) was the first identified oncoretrovirus, which infects and establishes a persistent infection in approximately 10-20 million people worldwide. Although only ~5% of infected individuals develop pathologies such as adult T-cell leukemia/lymphoma (ATLL) or a neuroinflammatory disorder termed HTLV-1-asssociated myelopathy/tropical spastic paraparesis (HAM/TSP), asymptomatic carriers are more susceptible to opportunistic infections. Furthermore, ATLL patients are severely immunosuppressed and prone to other malignancies and other infections. The HTLV-1 replication cycle provides ligands, mainly nucleic acids (RNA, RNA/DNA intermediates, ssDNA intermediates, and dsDNA), that are sensed by different pattern recognition receptors (PRRs) to trigger immune responses. However, the mechanisms of innate immune detection and immune responses to HTLV-1 infection are not well understood. In this review, we highlight the functional roles of different immune sensors in recognizing HTLV-1 infection in multiple cell types and the antiviral roles of host restriction factors in limiting persistent infection of HTLV-1. We also provide a comprehensive overview of intricate strategies employed by HTLV-1 to subvert the host innate immune response that may contribute to the development of HTLV-1-associated diseases. A more detailed understanding of HTLV-1-host pathogen interactions may inform novel strategies for HTLV-1 antivirals, vaccines, and treatments for ATLL or HAM/TSP.
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Affiliation(s)
- Suchitra Mohanty
- Department of Microbiology and Immunology, Penn State College of Medicine, Hershey, PA 17033, USA
| | - Edward W Harhaj
- Department of Microbiology and Immunology, Penn State College of Medicine, Hershey, PA 17033, USA
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Ahmadi Ghezeldasht S, Blackbourn DJ, Mosavat A, Rezaee SA. Pathogenicity and virulence of human T lymphotropic virus type-1 (HTLV-1) in oncogenesis: adult T-cell leukemia/lymphoma (ATLL). Crit Rev Clin Lab Sci 2023; 60:189-211. [PMID: 36593730 DOI: 10.1080/10408363.2022.2157791] [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: 01/04/2023]
Abstract
Adult T-cell leukemia/lymphoma (ATLL) is an aggressive malignancy of CD4+ T lymphocytes caused by human T lymphotropic virus type-1 (HTLV-1) infection. HTLV-1 was brought to the World Health Organization (WHO) and researchers to address its impact on global public health, oncogenicity, and deterioration of the host immune system toward autoimmunity. In a minority of the infected population (3-5%), it can induce inflammatory networks toward HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP), or hijacking the infected CD4+ T lymphocytes into T regulatory subpopulation, stimulating anti-inflammatory signaling networks, and prompting ATLL development. This review critically discusses the complex signaling networks in ATLL pathogenesis during virus-host interactions for better interpretation of oncogenicity and introduces the main candidates in the pathogenesis of ATLL. At least two viral factors, HTLV-1 trans-activator protein (TAX) and HTLV-1 basic leucine zipper factor (HBZ), are implicated in ATLL manifestation, interacting with host responses and deregulating cell signaling in favor of infected cell survival and virus dissemination. Such molecules can be used as potential novel biomarkers for ATLL prognosis or targets for therapy. Moreover, the challenging aspects of HTLV-1 oncogenesis introduced in this review could open new venues for further studies on acute leukemia pathogenesis. These features can aid in the discovery of effective immunotherapies when reversing the gene expression profile toward appropriate immune responses gradually becomes attainable.
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Affiliation(s)
- Sanaz Ahmadi Ghezeldasht
- Blood Borne Infections Research Center, Academic Center for Education, Culture, and Research (ACECR), Razavi Khorasan, Mashhad, Iran.,Immunology Research Center, Inflammation and Inflammatory Diseases Division, Mashhad University of Medical Sciences, Mashhad, Iran
| | | | - Arman Mosavat
- Blood Borne Infections Research Center, Academic Center for Education, Culture, and Research (ACECR), Razavi Khorasan, Mashhad, Iran
| | - Seyed Abdolrahim Rezaee
- Immunology Research Center, Inflammation and Inflammatory Diseases Division, Mashhad University of Medical Sciences, Mashhad, Iran
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Hijacking Host Immunity by the Human T-Cell Leukemia Virus Type-1: Implications for Therapeutic and Preventive Vaccines. Viruses 2022; 14:v14102084. [DOI: 10.3390/v14102084] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2022] [Revised: 09/15/2022] [Accepted: 09/16/2022] [Indexed: 11/16/2022] Open
Abstract
Human T-cell Leukemia virus type-1 (HTLV-1) causes adult T-cell leukemia/lymphoma (ATLL), HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP) and other inflammatory diseases. High viral DNA burden (VL) in peripheral blood mononuclear cells is a documented risk factor for ATLL and HAM/TSP, and patients with HAM/TSP have a higher VL in cerebrospinal fluid than in peripheral blood. VL alone is not sufficient to differentiate symptomatic patients from healthy carriers, suggesting the importance of other factors, including host immune response. HTLV-1 infection is life-long; CD4+-infected cells are not eradicated by the immune response because HTLV-1 inhibits the function of dendritic cells, monocytes, Natural Killer cells, and adaptive cytotoxic CD8+ responses. Although the majority of infected CD4+ T-cells adopt a resting phenotype, antigen stimulation may result in bursts of viral expression. The antigen-dependent “on-off” viral expression creates “conditional latency” that when combined with ineffective host responses precludes virus eradication. Epidemiological and clinical data suggest that the continuous attempt of the host immunity to eliminate infected cells results in chronic immune activation that can be further exacerbated by co-morbidities, resulting in the development of severe disease. We review cell and animal model studies that uncovered mechanisms used by HTLV-1 to usurp and/or counteract host immunity.
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Shallak M, Alberio T, Fasano M, Monti M, Iacobucci I, Ladet J, Mortreux F, Accolla RS, Forlani G. The endogenous HBZ interactome in ATL leukemic cells reveals an unprecedented complexity of host interacting partners involved in RNA splicing. Front Immunol 2022; 13:939863. [PMID: 35979358 PMCID: PMC9376625 DOI: 10.3389/fimmu.2022.939863] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2022] [Accepted: 07/07/2022] [Indexed: 11/13/2022] Open
Abstract
Adult T-cell leukemia/lymphoma (ATL) is a T-cell lymphoproliferative neoplasm caused by the human T-cell leukemia virus type 1 (HTLV-1). Two viral proteins, Tax-1 and HBZ play important roles in HTLV-1 infectivity and in HTLV-1-associated pathologies by altering key pathways of cell homeostasis. However, the molecular mechanisms through which the two viral proteins, particularly HBZ, induce and/or sustain the oncogenic process are still largely elusive. Previous results suggested that HBZ interaction with nuclear factors may alter cell cycle and cell proliferation. To have a more complete picture of the HBZ interactions, we investigated in detail the endogenous HBZ interactome in leukemic cells by immunoprecipitating the HBZ-interacting complexes of ATL-2 leukemic cells, followed by tandem mass spectrometry analyses. RNA seq analysis was performed to decipher the differential gene expression and splicing modifications related to HTLV-1. Here we compared ATL-2 with MOLT-4, a non HTLV-1 derived leukemic T cell line and further compared with HBZ-induced modifications in an isogenic system composed by Jurkat T cells and stably HBZ transfected Jurkat derivatives. The endogenous HBZ interactome of ATL-2 cells identified 249 interactors covering three main clusters corresponding to protein families mainly involved in mRNA splicing, nonsense-mediated RNA decay (NMD) and JAK-STAT signaling pathway. Here we analyzed in detail the cluster involved in RNA splicing. RNAseq analysis showed that HBZ specifically altered the transcription of many genes, including crucial oncogenes, by affecting different splicing events. Consistently, the two RNA helicases, members of the RNA splicing family, DDX5 and its paralog DDX17, recently shown to be involved in alternative splicing of cellular genes after NF-κB activation by HTLV-1 Tax-1, interacted and partially co-localized with HBZ. For the first time, a complete picture of the endogenous HBZ interactome was elucidated. The wide interaction of HBZ with molecules involved in RNA splicing and the subsequent transcriptome alteration strongly suggests an unprecedented complex role of the viral oncogene in the establishment of the leukemic state.
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Affiliation(s)
- Mariam Shallak
- Laboratories of General Pathology and Immunology “Giovanna Tosi”, Department of Medicine and Surgery, University of Insubria, Varese, Italy
| | - Tiziana Alberio
- Laboratory of Biochemistry and Functional Proteomics, Department of Science and High Technology, University of Insubria, Busto Arsizio, Italy
| | - Mauro Fasano
- Laboratory of Biochemistry and Functional Proteomics, Department of Science and High Technology, University of Insubria, Busto Arsizio, Italy
| | - Maria Monti
- Department of Chemical Sciences, University Federico II of Naples, Naples, Italy
- CEINGE Advanced Biotechnologies, Naples, Italy
| | - Ilaria Iacobucci
- Department of Chemical Sciences, University Federico II of Naples, Naples, Italy
- CEINGE Advanced Biotechnologies, Naples, Italy
| | - Julien Ladet
- Laboratory of Biology and Modeling of the Cell, CNRS UMR 5239, INSERM U1210, University of Lyon, Lyon, France
| | - Franck Mortreux
- Laboratory of Biology and Modeling of the Cell, CNRS UMR 5239, INSERM U1210, University of Lyon, Lyon, France
- *Correspondence: Franck Mortreux, ; Roberto S. Accolla, ; Greta Forlani,
| | - Roberto S. Accolla
- Laboratories of General Pathology and Immunology “Giovanna Tosi”, Department of Medicine and Surgery, University of Insubria, Varese, Italy
- *Correspondence: Franck Mortreux, ; Roberto S. Accolla, ; Greta Forlani,
| | - Greta Forlani
- Laboratories of General Pathology and Immunology “Giovanna Tosi”, Department of Medicine and Surgery, University of Insubria, Varese, Italy
- *Correspondence: Franck Mortreux, ; Roberto S. Accolla, ; Greta Forlani,
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El Hajj H, Bazarbachi A. Interplay between innate immunity and the viral oncoproteins Tax and HBZ in the pathogenesis and therapeutic response of HTLV-1 associated adult T cell leukemia. Front Immunol 2022; 13:957535. [PMID: 35935975 PMCID: PMC9352851 DOI: 10.3389/fimmu.2022.957535] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Accepted: 06/27/2022] [Indexed: 11/24/2022] Open
Abstract
The Human T-cell Leukemia virus type 1 (HTLV-1) causes an array of pathologies, the most aggressive of which is adult T-cell leukemia (ATL), a fatal blood malignancy with dismal prognosis. The progression of these diseases is partly ascribed to the failure of the immune system in controlling the spread of virally infected cells. HTLV-1 infected subjects, whether asymptomatic carriers or symptomatic patients are prone to opportunistic infections. An increasing body of literature emphasizes the interplay between HTLV-1, its associated pathologies, and the pivotal role of the host innate and adoptive immune system, in shaping the progression of HTLV-1 associated diseases and their response to therapy. In this review, we will describe the modalities adopted by the malignant ATL cells to subvert the host innate immune response with emphasis on the role of the two viral oncoproteins Tax and HBZ in this process. We will also provide a comprehensive overview on the function of innate immunity in the therapeutic response to chemotherapy, anti-viral or targeted therapies in the pre-clinical and clinical settings.
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Affiliation(s)
- Hiba El Hajj
- Department of Experimental Pathology, Immunology and Microbiology, Faculty of Medicine, American University of Beirut, Beirut, Lebanon
| | - Ali Bazarbachi
- Department of Internal Medicine, Faculty of Medicine, American University of Beirut, Beirut, Lebanon
- Department of Anatomy, Cell Biology and Physiological Sciences, Faculty of Medicine, American University of Beirut, Beirut, Lebanon
- *Correspondence: Ali Bazarbachi,
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Accolla RS. The Road to HTLV-1-Induced Leukemia by Following the Subcellular Localization of HTLV-1-Encoded HBZ Protein. Front Immunol 2022; 13:940131. [PMID: 35812456 PMCID: PMC9259882 DOI: 10.3389/fimmu.2022.940131] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2022] [Accepted: 06/01/2022] [Indexed: 11/13/2022] Open
Abstract
Human T cell leukemia virus-1 (HTLV-1) is the causative agent of a severe cancer of the lymphoid lineage that develops in 3-5% of infected individuals after many years. HTLV-1 infection may also induce a serious inflammatory pathology of the nervous system designated HTLV-associated myelopathy/tropical spastic paraparesis (HAM/TSP). Two virus-encoded proteins, the viral transactivator Tax-1 and the HTLV-1 basic leucine-zipper factor HBZ, are strongly involved in the oncogenic process. Tax-1 is involved in initial phases of the oncogenic process. Conversely, HBZ seems to be involved in maintenance of the neoplastic state as witnessed by the generation of leukemic/lymphomatous phenotype in HBZ transgenic mice and the persistent expression of HBZ in all phases of the oncogenic process. Nevertheless, the intimate molecular and cellular mechanism mediated by the two viral proteins, particularly HBZ, in oncogenesis still remain elusive. An important step toward the complete comprehension of HBZ-associated oncogenicity is the clarification of the anatomical correlates of HBZ during the various phases of HTLV-1 infection to development of HTLV-1-associated inflammatory pathology and ultimately to the establishment of leukemia. In this review, I will summarize recent studies that have established for the first time a temporal and unidirectional expression of HBZ, beginning with an exclusive cytoplasmic localization in infected asymptomatic individuals and in HAM/TSP patients and ending to a progressive cytoplasmic-to-nuclear transition in leukemic cells. These results are framed within the present knowledge of HTLV-1 infection and the future lines of research that may shed new light on the complex mechanism of HTLV-1- mediated oncogenesis.
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Gallo RC, Tagaya Y. Reflections on Some of the Exceptional Features of HTLV-1 and HTLV-1 Research: A Perspective. Front Immunol 2022; 13:859654. [PMID: 35432297 PMCID: PMC9010860 DOI: 10.3389/fimmu.2022.859654] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2022] [Accepted: 02/28/2022] [Indexed: 11/22/2022] Open
Abstract
The report is not a review or a summary. In a manner, it is a perspective but an unusual one. It looks back to the years my colleagues and I (RG) began preparing for human retroviruses (beginning in 1970), how they evolved, and attempts to bring to light or simply to emphasize many exceptional characteristics of a retrovirus known as HTLV-1 and some fortuitous coincidences, with emphasis on the needs of the field. These events cover over one half a century. We have had many reviews on HTLV-1 disease, epidemiology, and basic aspects of its replication, genome, gene functions, structure, and pathogenesis, though continued updates are needed. However, some of its truly exceptional features have not been highlighted, or at least not in a comprehensive manner. This article attempts to do so.
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Affiliation(s)
- Robert C. Gallo
- Institute of Human Virology, University of Maryland School of Medicine, Baltimore, MD, United States
- *Correspondence: Robert C. Gallo,
| | - Yutaka Tagaya
- Cell Biology Lab, Division of Virology, Pathogenesis and Cancer, Institute of Human Virology, University of Maryland School of Medicine, Baltimore, MD, United States
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Regulation of HTLV-1 Transformation. Biosci Rep 2022; 42:230803. [PMID: 35169839 PMCID: PMC8919135 DOI: 10.1042/bsr20211921] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2021] [Revised: 02/07/2022] [Accepted: 02/15/2022] [Indexed: 11/17/2022] Open
Abstract
Human T-cell leukemia virus type 1 (HTLV-1) is the only identified oncogenic human retrovirus. HTLV-1 infects approximately 5–10 million people worldwide and is the infectious cause of adult T-cell leukemia/lymphoma (ATL) and several chronic inflammatory diseases, including HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP), dermatitis, and uveitis. Unlike other oncogenic retroviruses, HTLV-1 does not capture a cellular proto-oncogene or induce proviral insertional mutagenesis. HTLV-1 is a trans-activating retrovirus and encodes accessory proteins that induce cellular transformation over an extended period of time, upwards of several years to decades. Inarguably the most important viral accessory protein involved in transformation is Tax. Tax is a multifunctional protein that regulates several different pathways and cellular processes. This single viral protein is able to modulate viral gene expression, activate NF-κB signaling pathways, deregulate the cell cycle, disrupt apoptosis, and induce genomic instability. The summation of these processes results in cellular transformation and virus-mediated oncogenesis. Interestingly, HTLV-1 also encodes a protein called Hbz from the antisense strand of the proviral genome that counters many Tax functions in the infected cell, such as Tax-mediated viral transcription and NF-κB activation. However, Hbz also promotes cellular proliferation, inhibits apoptosis, and disrupts genomic integrity. In addition to viral proteins, there are other cellular factors such as MEF-2, superoxide-generating NAPDH oxidase 5-α (Nox5α), and PDLIM2 which have been shown to be critical for HTLV-1-mediated T-cell transformation. This review will highlight the important viral and cellular factors involved in HTLV-1 transformation and the available in vitro and in vivo tools used to study this complex process.
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Tagaya Y. Is it NICE (nuclear import as a carcinogenic mechanism) to restrict HBZ in the cytoplasm? Haematologica 2021; 106:2038. [PMID: 33626868 PMCID: PMC8327722 DOI: 10.3324/haematol.2021.278377] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2021] [Indexed: 11/09/2022] Open
Affiliation(s)
- Yukata Tagaya
- Institute of Human Virology University of Maryland School of Medicine Baltimore MD
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Forlani G, Shallak M, Accolla RS, Romanelli MG. HTLV-1 Infection and Pathogenesis: New Insights from Cellular and Animal Models. Int J Mol Sci 2021; 22:ijms22158001. [PMID: 34360767 PMCID: PMC8347336 DOI: 10.3390/ijms22158001] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2021] [Revised: 07/22/2021] [Accepted: 07/24/2021] [Indexed: 12/12/2022] Open
Abstract
Since the discovery of the human T-cell leukemia virus-1 (HTLV-1), cellular and animal models have provided invaluable contributions in the knowledge of viral infection, transmission and progression of HTLV-associated diseases. HTLV-1 is the causative agent of the aggressive adult T-cell leukemia/lymphoma and inflammatory diseases such as the HTLV-1 associated myelopathy/tropical spastic paraparesis (HAM/TSP). Cell models contribute to defining the role of HTLV proteins, as well as the mechanisms of cell-to-cell transmission of the virus. Otherwise, selected and engineered animal models are currently applied to recapitulate in vivo the HTLV-1 associated pathogenesis and to verify the effectiveness of viral therapy and host immune response. Here we review the current cell models for studying virus–host interaction, cellular restriction factors and cell pathway deregulation mediated by HTLV products. We recapitulate the most effective animal models applied to investigate the pathogenesis of HTLV-1-associated diseases such as transgenic and humanized mice, rabbit and monkey models. Finally, we summarize the studies on STLV and BLV, two closely related HTLV-1 viruses in animals. The most recent anticancer and HAM/TSP therapies are also discussed in view of the most reliable experimental models that may accelerate the translation from the experimental findings to effective therapies in infected patients.
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Affiliation(s)
- Greta Forlani
- Laboratory of General Pathology and Immunology “Giovanna Tosi”, Department of Medicine and Surgery, University of Insubria, 21100 Varese, Italy; (G.F.); (M.S.); (R.S.A.)
| | - Mariam Shallak
- Laboratory of General Pathology and Immunology “Giovanna Tosi”, Department of Medicine and Surgery, University of Insubria, 21100 Varese, Italy; (G.F.); (M.S.); (R.S.A.)
| | - Roberto Sergio Accolla
- Laboratory of General Pathology and Immunology “Giovanna Tosi”, Department of Medicine and Surgery, University of Insubria, 21100 Varese, Italy; (G.F.); (M.S.); (R.S.A.)
| | - Maria Grazia Romanelli
- Department of Biosciences, Biomedicine and Movement Sciences, University of Verona, 37134 Verona, Italy
- Correspondence:
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