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Qasim A, Bhandari S, Peesapati VSR, Parikh HR, Baqui A. Adult T-Cell Lymphoma (ATL) With Erythroderma in Indolent Human T-Lymphotropic Virus Type I (HTLV-1) Infection. Cureus 2023; 15:e41264. [PMID: 37529824 PMCID: PMC10390346 DOI: 10.7759/cureus.41264] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/01/2023] [Indexed: 08/03/2023] Open
Abstract
Adult T-cell lymphoma (ATL) is a hematological malignancy of CD4+ mature T-lymphocytes commonly associated with chronic human T-lymphotropic virus type I (HTLV-1) infection. Chronic HTLV-1 infection induces oncogenic mutations in CD4+ T-cells, leading to an acute malignant transformation of host cells. Atypically, ATL presents with dermatological and pulmonary symptoms consistent with a "smoldering" disease pattern. We present a case of a 78-year-old male patient with chronic generalized malaise, progressively worsening shortness of breath, and diffuse erythroderma, who was diagnosed with ATL secondary to chronic indolent HTLV-1 infection. We evaluate the multisystemic clinical signs associated with ATL, the comprehensive clinical investigations required to reach a conclusive diagnosis, and the options for long-term clinical management.
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Affiliation(s)
- Abeer Qasim
- Internal Medicine, BronxCare Health System, Bronx, USA
| | | | | | - Harsh R Parikh
- Internal Medicine, St. George's University School of Medicine, St. George's, GRD
| | - Aam Baqui
- Pathology, BronxCare Health System, Bronx, USA
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Mehrabi Habibabadi H, Parsania M, Pourfathollah AA, Bahrami A, Sharifi Z. Prevalence and phylogenetic analysis of HTLV-1 in blood donors in Golestan Province, in the Northeast of Iran. J Virol Methods 2021; 290:114073. [PMID: 33485939 DOI: 10.1016/j.jviromet.2021.114073] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2020] [Revised: 12/07/2020] [Accepted: 01/16/2021] [Indexed: 10/22/2022]
Abstract
The human T-lymphotropic virus type 1 (HTLV-1) can cause ATL or TSP. This study evaluates the prevalence of HTLV-1 infection in blood donors in Golestan province. The study was conducted among 4226 blood donors and ELISA test was performed for the initial HTLV-1 screening. Reactive samples were confirmed by Western blot and Electrochemiluminescence tests. Then recalling donors with reactive results was done and genomic DNA from the new sample was extracted and tested using the Nested PCR method and phylogenetic analysis was performed. At first, 8 samples were reactive with ELISA test and 4 samples were confirmed with western blot, Electrochemiluminescence and Nested PCR tests.The sequences of isolates was related to the HTLV-1 virus and subtype a (cosmopolitan) subgroup A.The prevalence of HTLV-1 virus in Golestan province was about 0.09 %.The genotype of virus isolates had a common ancestor with isolates of the Khorasan region.
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Affiliation(s)
- Hossein Mehrabi Habibabadi
- Blood Transfusion Research Center, High Institute for Research and Education in Transfusion Medicine, Tehran, Iran
| | - Masoud Parsania
- Department of Microbiology, Faculty of Medicine, Tehran Medical Sciences, Islamic Azad University, Tehran, Iran
| | - Ali Akbar Pourfathollah
- Blood Transfusion Research Center, High Institute for Research and Education in Transfusion Medicine, Tehran, Iran; Department of Immunology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
| | - Asma Bahrami
- Blood Transfusion Research Center, High Institute for Research and Education in Transfusion Medicine, Tehran, Iran
| | - Zohreh Sharifi
- Blood Transfusion Research Center, High Institute for Research and Education in Transfusion Medicine, Tehran, Iran.
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Cancer Patients Have a Higher Risk Regarding COVID-19 - and Vice Versa? Pharmaceuticals (Basel) 2020; 13:ph13070143. [PMID: 32640723 PMCID: PMC7408191 DOI: 10.3390/ph13070143] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2020] [Revised: 06/24/2020] [Accepted: 07/03/2020] [Indexed: 02/06/2023] Open
Abstract
The world is currently suffering from a pandemic which has claimed the lives of over 230,000 people to date. The responsible virus is called severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and causes the coronavirus disease 2019 (COVID-19), which is mainly characterized by fever, cough and shortness of breath. In severe cases, the disease can lead to respiratory distress syndrome and septic shock, which are mostly fatal for the patient. The severity of disease progression was hypothesized to be related to an overshooting immune response and was correlated with age and comorbidities, including cancer. A lot of research has lately been focused on the pathogenesis and acute consequences of COVID-19. However, the possibility of long-term consequences caused by viral infections which has been shown for other viruses are not to be neglected. In this regard, this opinion discusses the interplay of SARS-CoV-2 infection and cancer with special focus on the inflammatory immune response and tissue damage caused by infection. We summarize the available literature on COVID-19 suggesting an increased risk for severe disease progression in cancer patients, and we discuss the possibility that SARS-CoV-2 could contribute to cancer development. We offer lines of thought to provide ideas for urgently needed studies on the potential long-term effects of SARS-CoV-2 infection.
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Habibabadi HM, Parsania M, Pourfathollah AA, Haghighat S, Sharifi Z. Association of TLR3 single nucleotide polymorphisms with susceptibility to HTLV-1 infection in Iranian asymptomatic blood donors. Rev Soc Bras Med Trop 2020; 53:e20200026. [PMID: 32578708 PMCID: PMC7310369 DOI: 10.1590/0037-8682-0026-2020] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2020] [Accepted: 04/03/2020] [Indexed: 01/06/2023] Open
Abstract
INTRODUCTION: The human T-lymphotropic virus type 1 (HTLV-1) has a single-stranded RNA genome and expresses specific proteins that have oncogenic potential. Approximately 15 to 20 million people worldwide have been infected by this virus. Changes in protein or gene expression are the effects of single nucleotide polymorphisms (SNPs) within the Toll-like receptor 3 (TLR3) gene. The function and efficacy of signal transduction also lead to modified immune responses. The present study aimed to investigate the association of SNPs within TLR3 (rs3775291 and rs3775296) with susceptibility to HTLV-1 infection in Iranian asymptomatic blood donors. METHODS: This study was performed on 100 HTLV-1-infected asymptomatic blood donors and 118 healthy blood donors. Genomic DNA from all participants was purified and then amplified using specific PCR primers. SNPs within TLR3 were evaluated using the restriction fragmentation length polymorphism technique, and the results were analyzed using SPSS software (version 22). RESULTS: The frequencies of the TLR3 (rs3775296) CC, CA, AA genotypes were 70%, 24%, and 6% in the patient group, and 50.8%, 44.9%, and 4.2% in the control group, respectively. There was a significant difference in the frequency distribution of TLR3 (rs3775296) genotypes and alleles, but not in the frequency distribution of TLR3 (rs3775291) genotypes between the patient and control groups. CONCLUSIONS: The TLR3 SNP rs3775296 was significantly associated with HTLV-1 infection and may be a protective factor against this viral infection.
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Affiliation(s)
- Hossein Mehrabi Habibabadi
- Department of Microbiology, Faculty of Advanced Science and Technology, Tehran Medical sciences, Islamic Azad University, Tehran, Iran
| | - Masoud Parsania
- Department of Microbiology, Faculty of Medicine, Tehran Medical sciences, Islamic Azad University, Tehran, Iran
| | - Ali Akbar Pourfathollah
- Department of Immunology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
| | - Setareh Haghighat
- Department of Microbiology, Faculty of Advanced Science and Technology, Tehran Medical sciences, Islamic Azad University, Tehran, Iran
| | - Zohreh Sharifi
- Blood Transfusion Research Center, High Institute for Research and Education in Transfusion Medicine, Tehran, Iran
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Azami M, Badfar G, Esmaeli E, Moslemirad M, Rahmati S. Epidemiology of human T-lymphotropic virus type 1 among blood donors and general population in Iran: a meta-analysis. Future Virol 2018. [DOI: 10.2217/fvl-2018-0015] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Aim: The present meta-analysis aims to assess the epidemiology of human T-lymphotropic virus type 1 (HTLV-1) among blood donors and general population in Iran. Methods: The present study was designed according to PRISMA guidelines. Results: The prevalence of HTLV-1 in 34 studies with a sample size of 3,626,364 blood donors was 0.20% (95% CI: 0.15–0.26) and the prevalence of this virus among men and women blood donors was 0.20% (95% CI: 0.15–0.27) and 0.64% (95% CI: 0.13–3.01), respectively and the female-male odds ratio was 3.13 (1.35–7.25, p = 0.008). In five studies consisting of 4763 individuals, the prevalence of HTLV-1 among the general population who lived in the main HTLV-1 endemic regions (Khorasan provinces, in northeastern Iran) was 2.5% (95% CI: 1.3–4.7) and the prevalence of this virus among men and women was 2.4% (95% CI: 0.8–7.1) and 3.4% (95% CI: 2.0–5.7), respectively. According to the systematic review, the prevalence of HTLV-1 in general population living in non-endemic regions of HTLV-1 was reported to be 0.07% to 1.8%. Conclusion: Considering the high prevalence of HTLV-1 in the main HTLV-1 endemic regions of Iran, persistent prevention programs are required in blood transfusion centers in these regions.
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Affiliation(s)
- Milad Azami
- Medical Student, Faculty of Medicine, Ilam University of Medical Sciences, Ilam, Iran
| | - Gholamreza Badfar
- Assistant Professor, Department of Pediatrics, Behbahan Faculty of Medical Sciences, Behbahan, Iran
| | - Elham Esmaeli
- Department of Microbiology & Clinical Microbiology Research Center, Ilam University of Medical Sciences, Ilam, Iran
| | - Moslem Moslemirad
- School of Nursing & Midwifery, Yasuj University of Medical Science, Yasuj, Iran
| | - Shoboo Rahmati
- Msc Epidemiology, School of Public Health, Ilam University of Medical Sciences, Ilam, Iran
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Panfil AR, Al-Saleem J, Howard CM, Shkriabai N, Kvaratskhelia M, Green PL. Stability of the HTLV-1 Antisense-Derived Protein, HBZ, Is Regulated by the E3 Ubiquitin-Protein Ligase, UBR5. Front Microbiol 2018; 9:80. [PMID: 29441057 PMCID: PMC5797633 DOI: 10.3389/fmicb.2018.00080] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2017] [Accepted: 01/12/2018] [Indexed: 12/25/2022] Open
Abstract
Human T-cell leukemia virus type 1 (HTLV-1) encodes a protein derived from the antisense strand of the proviral genome designated HBZ (HTLV-1 basic leucine zipper factor). HBZ is the only viral gene consistently expressed in infected patients and adult T-cell leukemia/lymphoma (ATL) tumor cell lines. It functions to antagonize many activities of the Tax viral transcriptional activator, suppresses apoptosis, and supports proliferation of ATL cells. Factors that regulate the stability of HBZ are thus important to the pathophysiology of ATL development. Using affinity-tagged protein and shotgun proteomics, we identified UBR5 as a novel HBZ-binding partner. UBR5 is an E3 ubiquitin-protein ligase that functions as a key regulator of the ubiquitin proteasome system in both cancer and developmental biology. Herein, we investigated the role of UBR5 in HTLV-1-mediated T-cell transformation and leukemia/lymphoma development. The UBR5/HBZ interaction was verified in vivo using over-expression constructs, as well as endogenously in T-cells. shRNA-mediated knockdown of UBR5 enhanced HBZ steady-state levels by stabilizing the HBZ protein. Interestingly, the related HTLV-2 antisense-derived protein, APH-2, also interacted with UBR5 in vivo. However, knockdown of UBR5 did not affect APH-2 protein stability. Co-immunoprecipitation assays identified ubiquitination of HBZ and knockdown of UBR5 resulted in a decrease in HBZ ubiquitination. MS/MS analysis identified seven ubiquitinated lysines in HBZ. Interestingly, UBR5 expression was upregulated in established T lymphocytic leukemia/lymphoma cell lines and the later stage of T-cell transformation in vitro. Finally, we demonstrated loss of UBR5 decreased cellular proliferation in transformed T-cell lines. Overall, our study provides evidence for UBR5 as a host cell E3 ubiquitin-protein ligase responsible for regulating HBZ protein stability. Additionally, our data suggests UBR5 plays an important role in maintaining the proliferative phenotype of transformed T-cell lines.
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Affiliation(s)
- Amanda R Panfil
- Department of Veterinary Biosciences, Center for Retrovirus Research, The Ohio State University, Columbus, OH, United States
| | - Jacob Al-Saleem
- Department of Veterinary Biosciences, Center for Retrovirus Research, The Ohio State University, Columbus, OH, United States
| | - Cory M Howard
- Department of Veterinary Biosciences, Center for Retrovirus Research, The Ohio State University, Columbus, OH, United States
| | - Nikoloz Shkriabai
- Division of Infectious Diseases, School of Medicine, University of Colorado Denver, Aurora, CO, United States
| | - Mamuka Kvaratskhelia
- Division of Infectious Diseases, School of Medicine, University of Colorado Denver, Aurora, CO, United States
| | - Patrick L Green
- Department of Veterinary Biosciences, Center for Retrovirus Research, The Ohio State University, Columbus, OH, United States.,Comprehensive Cancer Center and Solove Research Institute, The Ohio State University, Columbus, OH, United States
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Panfil AR, Martinez MP, Ratner L, Green PL. Human T-cell leukemia virus-associated malignancy. Curr Opin Virol 2016; 20:40-46. [PMID: 27591679 PMCID: PMC5102797 DOI: 10.1016/j.coviro.2016.08.009] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2016] [Revised: 08/05/2016] [Accepted: 08/16/2016] [Indexed: 12/30/2022]
Abstract
Human T-cell leukemia virus type 1 (HTLV-1) is a tumorigenic delta retrovirus and the causative infectious agent of a non-Hodgkin's peripheral T-cell malignancy called adult T-cell leukemia/lymphoma (ATL). ATL develops in approximately 5% of infected individuals after a significant clinical latency period of several decades. Clinical classifications of ATL include smoldering, chronic, lymphoma, and acute subtypes, with varying median survival ranges of a few months to several years. Depending on the ATL subtype and disease symptoms, treatment options include 'watchful waiting', chemotherapy, antiviral therapy, allogeneic hematopoietic stem cell transplantation (alloHSCT), and targeted therapies. Herein we review the characteristics and development of ATL, as well as current and future treatment options and perspectives.
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Affiliation(s)
- Amanda R Panfil
- Center for Retrovirus Research, Department of Veterinary Biosciences, The Ohio State University, Columbus, OH 43210, USA
| | - Michael P Martinez
- Center for Retrovirus Research, Department of Veterinary Biosciences, The Ohio State University, Columbus, OH 43210, USA
| | - Lee Ratner
- Department of Medicine, Division of Molecular Oncology, Washington University School of Medicine, St. Louis, MO, 63110, USA
| | - Patrick L Green
- Center for Retrovirus Research, Department of Veterinary Biosciences, The Ohio State University, Columbus, OH 43210, USA.
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Brenu EW, Ashton KJ, van Driel M, Staines DR, Peterson D, Atkinson GM, Marshall-Gradisnik SM. Cytotoxic lymphocyte microRNAs as prospective biomarkers for Chronic Fatigue Syndrome/Myalgic Encephalomyelitis. J Affect Disord 2012; 141:261-9. [PMID: 22572093 DOI: 10.1016/j.jad.2012.03.037] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/24/2011] [Revised: 03/11/2012] [Accepted: 03/12/2012] [Indexed: 10/28/2022]
Abstract
BACKGROUND Immune dysfunction associated with a disease often has a molecular basis. A novel group of molecules known as microRNAs (miRNAs) have been associated with suppression of translational processes involved in cellular development and proliferation, protein secretion, apoptosis, immune function and inflammatory processes. MicroRNAs may be implicated in Chronic Fatigue Syndrome/Myalgic Encephalomyelitis (CFS/ME), where immune function is impaired. The objective of this study was to determine the association between miRNAs in cytotoxic cells and CFS/ME. METHODS Natural Killer (NK) and CD8(+)T cells were preferentially isolated from peripheral blood mononuclear cells from all participants (CFS/ME, n=28; mean age=41.8±9.6 years and controls, n=28; mean age=45.3±11.7 years), via negative cell enrichment. Following total RNA extraction and subsequent synthesis of cDNA, reverse transcriptase-quantitative polymerase chain reaction (RT-qPCR) was used to determine the expression levels of nineteen miRNAs. RESULTS There was a significant reduction in the expression levels of miR-21, in both the NK and CD8(+)T cells in the CFS/ME sufferers. Additionally, the expression of miR-17-5p, miR-10a, miR-103, miR-152, miR-146a, miR-106, miR-223 and miR-191 was significantly decreased in NK cells of CFS/ME patients in comparison to the non-fatigued controls. LIMITATIONS The results from these investigations are not yet transferable into the clinical setting, further validatory studies are now required. CONCLUSIONS Collectively these miRNAs have been associated with apoptosis, cell cycle, development and immune function. Changes in miRNAs in cytotoxic cells may reduce the functional capacity of these cells and disrupt effective cytotoxic activity along with other immune functions in CFS/ME patients.
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Affiliation(s)
- Ekua W Brenu
- Faculty of Health Science and Medicine, Population Health and Neuroimmunology Unit, Bond University, Robina, Queensland, Australia.
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Cotranscriptional Chromatin Remodeling by Small RNA Species: An HTLV-1 Perspective. LEUKEMIA RESEARCH AND TREATMENT 2012; 2012:984754. [PMID: 23213554 PMCID: PMC3504244 DOI: 10.1155/2012/984754] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/23/2011] [Revised: 10/28/2011] [Accepted: 11/03/2011] [Indexed: 12/22/2022]
Abstract
Cell type specificity of human T cell leukemia virus 1 has been proposed as a possible reason for differential viral outcome in primary target cells versus secondary. Through chromatin remodeling, the HTLV-1 transactivator protein Tax interacts with cellular factors at the chromosomally integrated viral promoter to activate downstream genes and control viral transcription. RNA interference is the host innate defense mechanism mediated by short RNA species (siRNA or miRNA) that regulate gene expression. There exists a close collaborative functioning of cellular transcription factors with miRNA in order to regulate the expression of a number of eukaryotic genes including those involved in suppression of cell growth, induction of apoptosis, as well as repressing viral replication and propagation. In addition, it has been suggested that retroviral latency is influenced by chromatin alterations brought about by miRNA. Since Tax requires the assembly of transcriptional cofactors to carry out viral gene expression, there might be a close association between miRNA influencing chromatin alterations and Tax-mediated LTR activation. Herein we explore the possible interplay between HTLV-1 infection and miRNA pathways resulting in chromatin reorganization as one of the mechanisms determining HTLV-1 cell specificity and viral fate in different cell types.
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Pathogenesis of Metastatic Calcification and Acute Pancreatitis in Adult T-Cell Leukemia under Hypercalcemic State. LEUKEMIA RESEARCH AND TREATMENT 2011. [PMID: 23198151 PMCID: PMC3504271 DOI: 10.1155/2012/128617] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Human T-cell leukemia virus type-1 (HTLV-1) is the causative agent of adult T-cell leukemia (ATL). Hypercalcemia is common in patients with ATL. These patients rarely develop metastatic calcification and acute pancreatitis. The underlying pathogenesis of this condition is osteoclast hyperactivity with associated overproduction of parathyroid hormone-related protein, which results in hypercalcemia in association with bone demineralization. The discovery of the osteoclast differentiation factor receptor activator of nuclear factor-κB ligand (RANKL), its receptor RANK, and its decoy receptor osteoprotegerin (OPG), enhanced our understanding of the mechanisms of ATL-associated hypercalcemia. Macrophage inflammatory protein-1-α, tumor necrosis factor-α, interleukin-1, and interleukin-6 are important molecules that enhance the migration and differentiation of osteoclasts and the associated enhanced production of RANKL for osteoblast formation. In this paper, we focus on metastatic calcification and acute pancreatitis in ATL, highlighting recent advances in the understanding of the molecular role of the RANKL/RANK/OPG system including its interaction with various cytokines and calciotropic hormones in the regulation of osteoclastogenesis for bone resorption in hypercalcemic ATL patients.
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Interaction between the HTLV-1 envelope and cellular proteins: impact on virus infection and restriction. Future Med Chem 2011; 2:1651-68. [PMID: 21428837 DOI: 10.4155/fmc.10.255] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
The first human retrovirus, human T-lymphotropic virus 1 (HTLV-1), was discovered 30 years ago. Despite intensive study, the cell surface molecules involved in virus entry have only been identified over the past few years. Three molecules form the receptor complex for HTLV-1: glucose transporter 1, neuropilin 1 and heparan sulfate proteoglycans. Another molecule on the surface of dendritic cells, DC-SIGN, may play a role in dendritic cell-mediated infection of cells. In addition to the cell surface molecules used for entry, the HTLV-1 envelope interacts with cellular proteins, enabling the virus to traffic by exploiting cellular delivery pathways. To facilitate both these steps, HTLV-1 encodes motifs that mimic cellular binding partners for the trafficking system and ligands for the receptors. Here we review the interactions between the HTLV-1 envelope and cellular proteins.
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Bagossi P, Bander P, Bozóki B, Tözsér J. Discovery and significance of new human T-lymphotropic viruses: HTLV-3 and HTLV-4. Expert Rev Anti Infect Ther 2010; 7:1235-49. [PMID: 19968515 DOI: 10.1586/eri.09.97] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Human T-lymphotropic virus type 1 (HTLV-1) and type 2 (HTLV-2) were discovered approximately 30 years ago and they are associated with various lymphoproliferative and neurological diseases. The estimated number of infected people is 10-20 million worldwide. In 2005, two new HTLV-1/HTLV-2-related viruses were detected, HTLV-3 and HTLV-4, from the same geographical area of Africa. In the last 4 years, their complete genomic sequences were determined and some of their characteristic features were studied in detail. These newly discovered retroviruses alongside their human (HTLV-1 and -2) and animal relatives (simian T-lymphotropic virus type 1-3) are reviewed. The potential risks associated with these viruses and the potential antiretroviral therapies are also discussed.
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Affiliation(s)
- Péter Bagossi
- Department of Biochemistry and Molecular Biology, University of Debrecen, Debrecen, Hungary.
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Kurashina R, Ohyashiki JH, Kobayashi C, Hamamura R, Zhang Y, Hirano T, Ohyashiki K. Anti-proliferative activity of heat shock protein (Hsp) 90 inhibitors via β-catenin/TCF7L2 pathway in adult T cell leukemia cells. Cancer Lett 2009; 284:62-70. [DOI: 10.1016/j.canlet.2009.04.012] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2008] [Revised: 02/12/2009] [Accepted: 04/09/2009] [Indexed: 01/04/2023]
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Muraoka S, Ito Y, Kamimura M, Baba M, Arima N, Suda Y, Hashiguchi S, Torikai M, Nakashima T, Sugimura K. Effective Induction of Cell Death on Adult T-Cell Leukaemia Cells by HLA-DR -Specific Small Antibody Fragment Isolated from Human Antibody Phage Library. J Biochem 2009; 145:799-810. [DOI: 10.1093/jb/mvp039] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Agbottah E, Yeh WI, Berro R, Klase Z, Pedati C, Kehn-Hall K, Wu W, Kashanchi F. Two specific drugs, BMS-345541 and purvalanol A induce apoptosis of HTLV-1 infected cells through inhibition of the NF-kappaB and cell cycle pathways. AIDS Res Ther 2008; 5:12. [PMID: 18544167 PMCID: PMC2483717 DOI: 10.1186/1742-6405-5-12] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2007] [Accepted: 06/10/2008] [Indexed: 01/22/2023] Open
Abstract
Human T-cell leukemia virus type-1 (HTLV-1) induces adult T-cell leukemia/lymphoma (ATL/L), a fatal lymphoproliferative disorder, and HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP), a chronic progressive disease of the central nervous system after a long period of latent infection. Although the mechanism of transformation and leukemogenesis is not fully elucidated, there is evidence to suggest that the viral oncoprotein Tax plays a crucial role in these processes through the regulation of several pathways including NF-κB and the cell cycle pathways. The observation that NF-κB, which is strongly induced by Tax, is indispensable for the maintenance of the malignant phenotype of HTLV-1 by regulating the expression of various genes involved in cell cycle regulation and inhibition of apoptosis provides a possible molecular target for these infected cells. To develop potential new therapeutic strategies for HTLV-1 infected cells, in this present study, we initially screened a battery of NF-κB and CDK inhibitors (total of 35 compounds) to examine their effects on the growth and survival of infected T-cell lines. Two drugs namely BMS-345541 and Purvalanol A exhibited higher levels of growth inhibition and apoptosis in infected cell as compared to uninfected cells. BMS-345541 inhibited IKKβ kinase activity from HTLV-1 infected cells with an IC50 (the 50% of inhibitory concentration) value of 50 nM compared to 500 nM from control cells as measured by in vitro kinase assays. The effects of Purvalanol A were associated with suppression of CDK2/cyclin E complex activity as previously shown by us. Combination of both BMS-345541 and Purvalanol A showed a reduced level of HTLV-1 p19 Gag production in cell culture. The apparent apoptosis in these infected cells were associated with increased caspase-3 activity and PARP cleavage. The potent and selective apoptotic effects of these drugs suggest that both BMS-345541 and Purvalanol A, which target both NF-κB and CDK complex and the G1/S border, might be promising new agents in the treatment of these infected patients.
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Hamamura RS, Ohyashiki JH, Kurashina R, Kobayashi C, Zhang Y, Takaku T, Ohyashiki K. Induction of heme oxygenase-1 by cobalt protoporphyrin enhances the antitumour effect of bortezomib in adult T-cell leukaemia cells. Br J Cancer 2007; 97:1099-105. [PMID: 17895889 PMCID: PMC2360455 DOI: 10.1038/sj.bjc.6604003] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Adult T-cell leukaemia (ATL) is a lethal neoplasia derived from HTLV-1-infected T lymphocytes frequently exhibiting nuclear factor-κB (NF-κB) activation. Despite the use of various treatment regimens, the prognosis of ATL is poor, and new treatment strategies are urgently needed. We therefore explored the effect and the molecular mechanism of a proteasome inhibitor, bortezomib, in ATL cells. We found bortezomib-induced cell death, and bortezomib suppressed constitutive NF-κB activation via I-κB stabilisation in three ATL cell lines (TaY, MT-2 and MT-4). An oligonucleotide DNA microarray analysis of TaY cells revealed upregulation of genes encoding heat shock proteins (HSPA1A, STIP1, HSPA1B, and HSPCA), genes related to protein folding (CDC37 and ANAPC5), Fas-associated factor 1(FAF1) and an oxidative stress-related gene, heme oxygenase-1(HMOX-1), known to be a target gene of hypoxia-inducible gene-1 alpha (HIF-1 alpha). Cobalt protoporphyrin induced HMOX-1, instead of HIF-1 alpha expression and increased bortezomib-induced apoptosis in the presence of pharmacologically effective doses of bortezomib. In contrast, zinc protoporphyrin downregulated HMOX-1 expression, thereby partially inhibiting bortezomib-induced cell death. This indicates that HMOX-1 may modulate anticancer effects of bortezomib in ATL cells, and could be a molecular target in treating ATL patients.
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Affiliation(s)
- R S Hamamura
- Department of Internal Medicine, Tokyo Medical University, Tokyo, Japan
| | - J H Ohyashiki
- Intractable Immune System Disease Research Center, Tokyo Medical University, Tokyo, Japan
- Intractable Immune System Disease Research Center, Tokyo Medical University, 6-7-1, Nishi-shinjuku, Shinjuku-ku, Tokyo 160-0023, Japan. E-mail:
| | - R Kurashina
- Department of Internal Medicine, Tokyo Medical University, Tokyo, Japan
- Department of Clinical Pharmacology, Tokyo University of Pharmacy and Life Sciences, Tokyo, Japan
| | - C Kobayashi
- Department of Internal Medicine, Tokyo Medical University, Tokyo, Japan
| | - Y Zhang
- Department of Internal Medicine, Tokyo Medical University, Tokyo, Japan
| | - T Takaku
- Department of Internal Medicine, Tokyo Medical University, Tokyo, Japan
| | - K Ohyashiki
- Department of Internal Medicine, Tokyo Medical University, Tokyo, Japan
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17
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Lyell V, Khatamzas E, Allain T. Severe hypercalcaemia and lymphoma in an HTLV-1 positive Jamaican woman: a case report. J Med Case Rep 2007; 1:56. [PMID: 17651486 PMCID: PMC1950877 DOI: 10.1186/1752-1947-1-56] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2007] [Accepted: 07/25/2007] [Indexed: 11/16/2022] Open
Abstract
Human T cell lymphotrophic virus type-1 infection is endemic in the Afro-Caribbean community in Britain, with carriage rates of about 3%. Although there is a long latency, carriers have a 1–5% chance of developing adult T cell leukaemia/lymphoma, a condition frequently complicated by marked and refractory hypercalcaemia, and with a poor prognosis. We present the case of an elderly Jamaican woman with severe hypercalcaemia and a raised PTHrP who was found to have lymphoma and was positive for HTLV-1.
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Affiliation(s)
- Veronica Lyell
- Department of Care of the Elderly, Southmead Hospital, Bristol, UK
| | - Elham Khatamzas
- Department of Care of the Elderly, Southmead Hospital, Bristol, UK
| | - Theresa Allain
- Department of Care of the Elderly, Southmead Hospital, Bristol, UK
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18
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Matsuoka M, Jeang KT. Human T-cell leukaemia virus type 1 (HTLV-1) infectivity and cellular transformation. Nat Rev Cancer 2007; 7:270-80. [PMID: 17384582 DOI: 10.1038/nrc2111] [Citation(s) in RCA: 608] [Impact Index Per Article: 35.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
It has been 30 years since a 'new' leukaemia termed adult T-cell leukaemia (ATL) was described in Japan, and more than 25 years since the isolation of the retrovirus, human T-cell leukaemia virus type 1 (HTLV-1), that causes this disease. We discuss HTLV-1 infectivity and how the HTLV-1 Tax oncoprotein initiates transformation by creating a cellular environment favouring aneuploidy and clastogenic DNA damage. We also explore the contribution of a newly discovered protein and RNA on the HTLV-1 minus strand, HTLV-1 basic leucine zipper factor (HBZ), to the maintenance of virus-induced leukaemia.
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Affiliation(s)
- Masao Matsuoka
- Laboratory of Virus Immunology, Institute for Virus Research, Kyoto University, Japan
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19
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Miyazaki M, Yasunaga JI, Taniguchi Y, Tamiya S, Nakahata T, Matsuoka M. Preferential selection of human T-cell leukemia virus type 1 provirus lacking the 5' long terminal repeat during oncogenesis. J Virol 2007; 81:5714-23. [PMID: 17344291 PMCID: PMC1900290 DOI: 10.1128/jvi.02511-06] [Citation(s) in RCA: 87] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
In adult T-cell leukemia (ATL) cells, a defective human T-cell leukemia virus type 1 (HTLV-1) provirus lacking the 5' long terminal repeat (LTR), designated type 2 defective provirus, is frequently observed. To investigate the mechanism underlying the generation of the defective provirus, we sequenced HTLV-1 provirus integration sites from cases of ATL. In HTLV-1 proviruses retaining both LTRs, 6-bp repeat sequences were adjacent to the 5' and 3' LTRs. In 8 of 12 cases with type 2 defective provirus, 6-bp repeats were identified at both ends. In five of these cases, a short repeat was bound to CA dinucleotides of the pol and env genes at the 5' end, suggesting that these type 2 defective proviruses were formed before integration. In four cases lacking the 6-bp repeat, short (6- to 26-bp) deletions in the host genome were identified, indicating that these defective proviruses were generated after integration. Quantification indicated frequencies of type 2 defective provirus of less than 3.9% for two carriers, which are much lower than those seen for ATL cases (27.8%). In type 2 defective proviruses, the second exons of the tax, rex, and p30 genes were frequently deleted, leaving Tax unable to activate NF-kappaB and CREB pathways. The HTLV-1 bZIP factor gene, located on the minus strand, is expressed in ATL cells with this defective provirus, and its coding sequences are intact, suggesting its significance in oncogenesis.
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Affiliation(s)
- Maki Miyazaki
- Laboratory of Virus Immunology, Institute for Virus Research, Kyoto University, Shogoin Kawara-cho 53, Sakyo-ku, Kyoto 606-8507, Japan
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20
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Twizere JC, Springael JY, Boxus M, Burny A, Dequiedt F, Dewulf JF, Duchateau J, Portetelle D, Urbain P, Van Lint C, Green PL, Mahieux R, Parmentier M, Willems L, Kettmann R. Human T-cell leukemia virus type-1 Tax oncoprotein regulates G-protein signaling. Blood 2006; 109:1051-60. [PMID: 16990599 PMCID: PMC1785145 DOI: 10.1182/blood-2006-06-026781] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Human T-cell leukemia virus type-1 (HTLV-1) is associated with adult T-cell leukemia (ATL) and neurological syndromes. HTLV-1 encodes the oncoprotein Tax-1, which modulates viral and cellular gene expression leading to T-cell transformation. Guanine nucleotide-binding proteins (G proteins) and G protein-coupled receptors (GPCRs) constitute the largest family of membrane proteins known and are involved in the regulation of most biological functions. Here, we report an interaction between HTLV-1 Tax oncoprotein and the G-protein beta subunit. Interestingly, though the G-protein beta subunit inhibits Tax-mediated viral transcription, Tax-1 perturbs G-protein beta subcellular localization. Functional evidence for these observations was obtained using conditional Tax-1-expressing transformed T-lymphocytes, where Tax expression correlated with activation of the SDF-1/CXCR4 axis. Our data indicated that HTLV-1 developed a strategy based on the activation of the SDF-1/CXCR4 axis in the infected cell; this could have tremendous implications for new therapeutic strategies.
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21
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Siu YT, Chin KT, Siu KL, Yee Wai Choy E, Jeang KT, Jin DY. TORC1 and TORC2 coactivators are required for tax activation of the human T-cell leukemia virus type 1 long terminal repeats. J Virol 2006; 80:7052-9. [PMID: 16809310 PMCID: PMC1489057 DOI: 10.1128/jvi.00103-06] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Human T-cell leukemia virus type 1 (HTLV-1) Tax protein activates viral transcription from the long terminal repeats (LTR). Mechanisms through which Tax activates LTR have been established, but coactivators of this process remain to be identified and characterized. Here we show that all three members of the TORC family of transcriptional regulators are coactivators of Tax for LTR-driven expression. TORC coactivation requires CREB, but not ATF4 or other bZIP factors. Tax physically interacts with TORC1, TORC2, and TORC3 (TORC1/2/3), and the depletion of TORC1/2/3 inhibited Tax activity. TORC coactivation can be further enhanced by transcriptional coactivator p300. In addition, coactivators in the p300 family are required for full activity of Tax independently of TORC1/2/3. Thus, both TORC and p300 families of coactivators are essential for optimal activation of HTLV-1 transcription by Tax.
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Affiliation(s)
- Yeung-Tung Siu
- Department of Biochemistry, The University of Hong Kong, 3/F Laboratory Block, Faculty of Medicine Building, 21 Sassoon Road, Pokfulam, Hong Kong
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22
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Miyazato P, Yasunaga JI, Taniguchi Y, Koyanagi Y, Mitsuya H, Matsuoka M. De novo human T-cell leukemia virus type 1 infection of human lymphocytes in NOD-SCID, common gamma-chain knockout mice. J Virol 2006; 80:10683-91. [PMID: 16943297 PMCID: PMC1641804 DOI: 10.1128/jvi.01009-06] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Human T-cell leukemia virus type 1 (HTLV-1) is the etiologic agent of adult T-cell leukemia, a disease that is triggered after a long latency period. HTLV-1 is known to spread through cell-to-cell contact. In an attempt to study the events in early stages of HTLV-1 infection, we inoculated uninfected human peripheral blood mononuclear cells and the HTLV-1-producing cell line MT-2 into NOD-SCID, common gamma-chain knockout mice (human PBMC-NOG mice). HTLV-1 infection was confirmed with the detection of proviral DNA in recovered samples. Both CD4+ and CD8+ T cells were found to harbor the provirus, although the latter population harbored provirus to a lesser extent. Proviral loads increased with time, and inverse PCR analysis revealed the oligoclonal proliferation of infected cells. Although tax gene transcription was suppressed in human PBMC-NOG mice, it increased after in vitro culture. This is similar to the phenotype of HTLV-1-infected cells isolated from HTLV-1 carriers. Furthermore, the reverse transcriptase inhibitors azidothymidine and tenofovir blocked primary infection in human PBMC-NOG mice. However, when tenofovir was administered 1 week after infection, the proviral loads did not differ from those of untreated mice, indicating that after initial infection, clonal proliferation of infected cells was predominant over de novo infection of previously uninfected cells. In this study, we demonstrated that the human PBMC-NOG mouse model should be a useful tool in studying the early stages of primary HTLV-1 infection.
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Affiliation(s)
- Paola Miyazato
- Laboratory of Virus Immunology, Institute for Virus Research, Kyoto University, Shogoin Kawahara-cho 53, Sakyo-ku, Kyoto 606-8507, Japan.
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23
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Ching YP, Chan SF, Jeang KT, Jin DY. The retroviral oncoprotein Tax targets the coiled-coil centrosomal protein TAX1BP2 to induce centrosome overduplication. Nat Cell Biol 2006; 8:717-24. [PMID: 16767081 DOI: 10.1038/ncb1432] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2006] [Accepted: 04/13/2006] [Indexed: 12/18/2022]
Abstract
Emerging evidence suggests that supernumerary centrosomes drive genome instability and oncogenesis. Human T-cell leukaemia virus type I (HTLV-I) is etiologically associated with adult T-cell leukaemia (ATL). ATL cells are aneuploid, but the causes of aneuploidy are incompletely understood. Here, we show that centrosome amplification is frequent in HTLV-I-transformed cells and that this phenotype is caused by the viral Tax oncoprotein. We also show that the fraction of Tax protein that localizes to centrosomes interacts with TAX1BP2, a novel centrosomal protein composed almost entirely of coiled-coil domains. Overexpression of TAX1BP2 inhibited centrosome duplication, whereas depletion of TAX1BP2 by RNAi resulted in centrosome hyperamplification. Our findings suggest that the HTLV-I Tax oncoprotein targets TAX1BP2 causing genomic instability and aneuploidy.
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Affiliation(s)
- Yick-Pang Ching
- Department of Biochemistry, University of Hong Kong, 21 Sassoon Road, Pokfulam, Hong Kong
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24
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Fujiwara H, Nakamura D, Kukita T, Hamada H, Ozaki A, Matsushita K, Matsumoto T, Tei C. Immunosuppressive treatment for mixed connective tissue disease may facilitate the development of adult T cell leukemia/lymphoma in a HTLVI carrier. Intern Med 2006; 45:297-301. [PMID: 16595998 DOI: 10.2169/internalmedicine.45.1490] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
A 66-year-old woman who was positive for human T-lymphotropic virus type I (HTLV-I) antibody developed mixed connective tissue disease (MCTD) with interstitial pneumonia, and was successfully treated with corticosteroid. One year later, under maintenance treatment of prednisolone (PSL), she contracted acute type adult Tcell leukemia/lymphoma (ATLL) without flaring of MCTD. MCTD is considered to be as one of the HTL-V-I-related inflammatory diseases, however the development of ATLL during the treatment of HTL-V-I-related MCTD has not been well studied. Here, we review the literature and raise the issue of the mutual interactions between MCTD-causative anti-HTLV-I immune response and anti-ATLL immune response.
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Affiliation(s)
- Hiroshi Fujiwara
- Division of Hematology and Immunology, Department of Internal Medicine, Kagoshima University, Kagoshima, Sakuragaoka
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25
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Ravandi F, O'Brien S. Chronic lymphoid leukemias other than chronic lymphocytic leukemia: diagnosis and treatment. Mayo Clin Proc 2005; 80:1660-74. [PMID: 16342661 DOI: 10.4065/80.12.1660] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The World Health Organization classification divides lymphoid malignancies into precursor B-cell and T-cell neoplasms as well as mature B-cell and T-cell neoplasms. Mature B-cell neoplasms comprise more than 85% of non-Hodgkin lymphomas worldwide and can be further subclassified according to the postulated cell of origin by using specific morphologic, immunophenotypic, and molecular characteristics. Similarly, the more uncommon mature T-cell neoplasms have been better characterized to include numerous distinct entities with widely varying natural histories. The distinction between lymphoma and leukemia is somewhat arbitrary and is based on variable involvement of the bone marrow, peripheral blood, and lymphatic system. In this article, we review the diagnostic and clinical features of mature B-cell and T-cell lymphoproliferative disorders that commonly have a leukemic presentation.
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MESH Headings
- Diagnosis, Differential
- Humans
- Leukemia, Hairy Cell/diagnosis
- Leukemia, Hairy Cell/therapy
- Leukemia, Lymphocytic, Chronic, B-Cell/diagnosis
- Leukemia, Lymphocytic, Chronic, B-Cell/therapy
- Leukemia, T-Cell/diagnosis
- Leukemia, T-Cell/therapy
- Prognosis
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Affiliation(s)
- Farhad Ravandi
- Department of Leukemia, The University of Texas M D Anderson Cancer Center, Houston 77030, USA.
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26
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Tabakin-Fix Y, Azran I, Schavinky-Khrapunsky Y, Levy O, Aboud M. Functional inactivation of p53 by human T-cell leukemia virus type 1 Tax protein: mechanisms and clinical implications. Carcinogenesis 2005; 27:673-81. [PMID: 16308315 DOI: 10.1093/carcin/bgi274] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Human T-cell leukemia virus type 1 (HTLV-I) has been implicated with the etiology of adult T-cell leukemia (ATL) and certain other clinical disorders. Although the leukemogenic mechanism of HTLV-1 is not fully understood yet, the viral Tax protein is widely regarded as a key factor in this mechanism. Tax can modulate the synthesis or function of many regulatory factors which control a wide range of normal and oncogenic cellular processes and therefore, it acts as a potent oncoprotein. In the last few years, special attention has been attracted to Tax interference with the transactivation function of p53, a tumor-suppressor protein that is involved in regulation of the cell-cycle and apoptosis and in maintaining the cellular genome integrity. p53 is mutated in approximately 60% of all human tumors. In contrast, mutant p53 is found in only small percentage of ATL patients. Nevertheless, p53 is inactive in the leukemic cells of most ATL patients and in most HTLV-1 transformed cells. By inactivating p53, Tax can immortalize the HTLV-1-infected cells and destabilize their genome. Consequently, such cells can progress toward the ultimate leukemic state by a stepwise accumulation of oncogenic mutations and other types of chromosomal aberrations. Furthermore, since p53 exists in most ATL patients in its wild-type form, its reactivation by therapeutic drugs might be an effective approach for ATL therapy. Several mechanisms have been proposed so far for Tax-induced p53 inactivation. Understanding the exact mechanism of this Tax effect is essential for designing effective means for this therapeutic approach. In this review article, we discuss the various mechanisms proposed for Tax interference with p53 functions and their clinical and therapeutic implications.
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Affiliation(s)
- Yulia Tabakin-Fix
- Department of Microbiology and Immunology, Cancer Research Center, Faculty of Health Sciences and Department of Life Sciences, Ben Gurion University of the Negev, Beer Sheva 84105, Israel
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27
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Taylor GP, Matsuoka M. Natural history of adult T-cell leukemia/lymphoma and approaches to therapy. Oncogene 2005; 24:6047-57. [PMID: 16155611 DOI: 10.1038/sj.onc.1208979] [Citation(s) in RCA: 152] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
After cell-to-cell transmission, HTLV-I increases its viral genome by de novo infection and proliferation of infected cells. Proliferation of infected cells is clonal and persistent in vivo. During the carrier state, infected cells are selected in vivo by the host's immune system, the genetic and epigenetic environment of proviral integration sites, and other factors. In leukemic cells, tax gene expression is frequently impaired by genetic and epigenetic mechanisms. Such loss of Tax expression enables ATL cells to escape the host immune system. On the other hand, ATL cells acquire the ability to proliferate without Tax by intracellular genetic and epigenetic changes. Despite advances in support and the development of novel treatment agents, the prognosis for ATLL remains poor. A number of therapies, however, do appear to improve prognosis compared to CHOP (VEPA). These include interferon-alpha plus zidovudine (probably after 1-2 cycles of CHOP), intensive chemotherapy as in LSG-15 with G-CSF support and Allo-SCT (which includes the potential for cure). Emerging novel approaches include HDAC inhibitors, monoclonal antibodies, and proteasome inhibitors. Comparison between different therapeutic approaches is complicated by the range of natural history of ATLL, different recruitments of naïve-to-therapy, refractory or relapsed patients, and variations in the reporting of outcome that frequently excludes difficult-to-evaluate patients. Moreover, results from relatively small proof-of-principle studies have not been extended with randomized, controlled trials. As a result, currently, there is no clear evidence to support the value of any particular treatment approach over others. To avoid further unnecessary patient suffering and to identify optimal therapy as rapidly as possible, large randomized, controlled trials encompassing multicenter, international collaborations will be necessary.
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Affiliation(s)
- Graham P Taylor
- Department of GU Medicine & Communicable Diseases, Faculty of Medicine, Imperial College, Norfolk Place, London W2 1PG, UK
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