1
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Cengiz M, Sezer CV, Gür B, Bayrakdar A, İzgördü H, Alanyalı F, Öziç C, Kutlu HM. The role of ceranib-2 and its nanoform on the decrease of telomerase levels in human non-small cell cancer. Mol Biol Rep 2024; 51:889. [PMID: 39105852 DOI: 10.1007/s11033-024-09838-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2024] [Accepted: 07/31/2024] [Indexed: 08/07/2024]
Abstract
BACKGROUND Ceranib-2, an acid ceramidase (AC) inhibitor, can inhibit cancer cell proliferation and tumor development. However, poor water solubility and low cellular bioavailability limit its efficacy in cancer treatment. METHODS AND RESULTS This study aimed to investigate the cell death induced by ceranib-2 and its solid lipid nanoformulation (ceranib-2-SLN) produced by the hot homogenization technique and the synergistic relationship between ceramide and telomerase in vitro and in silico. Furthermore, this study proved the possible mechanism of ceranib-2-induced AC inhibition by in silico studies. The effective cytotoxic concentrations of ceranib-2, telomerase level, and changes in ceramide levels were measured by MTT colorimetric cytotoxicity assay, ELISA, and LC/MS/MS methods, respectively. TEM results showed that ceranib-2-SLN was 13-fold smaller than the size of ceranib-2. Ceranib-2 and ceranib-2-SLN had IC50 concentrations of 31.62 (± 2.1) and 27.69 (± 1.75) µM in A549, and 48.79 (± 1.56) and 67.98 (± 2.33) in Beas-2B cells. These compounds simultaneously increased ceramide levels and decreased telomerase levels in A549 cells. Ceranib-2 increased telomerase levels while decreasing ceramide levels in Beas-2B cells. It was shown how the synergistic impact of ceranib-2-induced ceramide production and ceramide-induced telomerase level reduction on cytotoxicity in A549 cells. CONCLUSIONS Ceranib-2-SLN was discovered to be more cytotoxic on cancer cells than ceranib-2, suggesting that it could be a promising option for the development of a new anti-cancer agent.
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Affiliation(s)
- Mustafa Cengiz
- Department of Elementary Education, Faculty of Education, Siirt University, Siirt, 56100, Türkiye.
| | - Canan Vejselova Sezer
- Department of Biology, Faculty of Science, Eskişehir Technical University, Eskişehir, 26470, Türkiye
| | - Bahri Gür
- Department of Biochemistry, Faculty of Sciences and Arts, Iğdır University, Iğdır, 76300, Türkiye.
| | - Alpaslan Bayrakdar
- Vocational School of Higher Education for Healthcare Services, Iğdır University, Iğdır, 76000, Türkiye
| | - Hüseyin İzgördü
- Department of Biology, Faculty of Science, Eskişehir Technical University, Eskişehir, 26470, Türkiye
| | - Filiz Alanyalı
- Department of Biology, Faculty of Science, Eskişehir Technical University, Eskişehir, 26470, Türkiye
| | - Cem Öziç
- Department of Medical Biology, Kafkas University, Medicine Faculty, Ahmet Arslan Street, Kars, 36100, Türkiye
| | - Hatice Mehtap Kutlu
- Department of Biology, Faculty of Science, Eskişehir Technical University, Eskişehir, 26470, Türkiye
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2
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Waitkus MS, Erman EN, Reitman ZJ, Ashley DM. Mechanisms of telomere maintenance and associated therapeutic vulnerabilities in malignant gliomas. Neuro Oncol 2024; 26:1012-1024. [PMID: 38285162 PMCID: PMC11145458 DOI: 10.1093/neuonc/noae016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2023] [Indexed: 01/30/2024] Open
Abstract
A majority of cancers (~85%) activate the enzyme telomerase to maintain telomere length over multiple rounds of cellular division. Telomerase-negative cancers activate a distinct, telomerase-independent mechanism of telomere maintenance termed alternative lengthening of telomeres (ALT). ALT uses homologous recombination to maintain telomere length and exhibits features of break-induced DNA replication. In malignant gliomas, the activation of either telomerase or ALT is nearly ubiquitous in pediatric and adult tumors, and the frequency with which these distinct telomere maintenance mechanisms (TMMs) is activated varies according to genetically defined glioma subtypes. In this review, we summarize the current state of the field of TMMs and their relevance to glioma biology and therapy. We review the genetic alterations and molecular mechanisms leading to telomerase activation or ALT induction in pediatric and adult gliomas. With this background, we review emerging evidence on strategies for targeting TMMs for glioma therapy. Finally, we comment on critical gaps and issues for moving the field forward to translate our improved understanding of glioma telomere maintenance into better therapeutic strategies for patients.
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Affiliation(s)
- Matthew S Waitkus
- The Preston Robert Tisch Brain Tumor Center, Duke University Medical Center, Durham, North Carolina, USA
- Department of Neurosurgery, Duke University Medical Center, Durham, North Carolina, USA
| | - Elise N Erman
- The Preston Robert Tisch Brain Tumor Center, Duke University Medical Center, Durham, North Carolina, USA
- Department of Neurosurgery, Duke University Medical Center, Durham, North Carolina, USA
| | - Zachary J Reitman
- The Preston Robert Tisch Brain Tumor Center, Duke University Medical Center, Durham, North Carolina, USA
- Department of Radiation Oncology, Duke University Medical Center, Durham, North Carolina, USA
| | - David M Ashley
- The Preston Robert Tisch Brain Tumor Center, Duke University Medical Center, Durham, North Carolina, USA
- Department of Neurosurgery, Duke University Medical Center, Durham, North Carolina, USA
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3
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Cheng D, Zhang F, Porter KI, Wang S, Zhang H, Davis CJ, Robertson GP, Zhu J. Humanization of the mouse Tert gene reset telomeres to human length. RESEARCH SQUARE 2024:rs.3.rs-3617723. [PMID: 38260456 PMCID: PMC10802727 DOI: 10.21203/rs.3.rs-3617723/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2024]
Abstract
Telomeres undergo shortening with each cell division, serving as biomarkers of human aging, which is characterized by short telomeres and restricted telomerase expression in adult tissues. Contrarily, mice, featuring their longer telomeres and widespread telomerase activity, present limitations as models for understanding telomere-related human biology and diseases. To bridge this gap, we engineered a mouse strain with a humanized mTert gene, hmTert, wherein specific non-coding sequences were replaced with their human counterparts. The hmTert gene, encoding the wildtype mTert protein, was repressed in adult tissues beyond the gonads and thymus, closely resembling the regulatory pattern of the human TERT gene. Remarkably, the hmTert gene rescued telomere dysfunction in late generations of mTert-knockout mice. Through successive intercrosses of Terth/- mice, telomere length progressively declined, stabilizing below 10-kb. Terth/h mice achieved a human-like average telomere length of 10-12 kb, contrasting with the 50-kb length in wildtype C57BL/6J mice. Despite shortened telomeres, Terth/h mice maintained normal body weight and cell homeostasis in highly proliferative tissues. Notably, colonocyte proliferation decreased significantly in Terth/h mice during dextran sodium sulfate-induced ulcerative colitis-like pathology, suggesting limitations on cellular renewal due to short telomeres. Our findings underscore the genetic determination of telomere homeostasis in mice by the Tert gene. These mice, exhibiting humanized telomere homeostasis, serve as a valuable model for exploring fundamental questions related to human aging and cancer.
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Affiliation(s)
- De Cheng
- Department of Pharmaceutical Sciences, College of Pharmacy and Pharmaceutical Sciences, Washington State University, Spokane, WA 99202, USA
| | - Fan Zhang
- Department of Pharmaceutical Sciences, College of Pharmacy and Pharmaceutical Sciences, Washington State University, Spokane, WA 99202, USA
| | - Kenneth I. Porter
- Department of Pharmaceutical Sciences, College of Pharmacy and Pharmaceutical Sciences, Washington State University, Spokane, WA 99202, USA
| | - Shuwen Wang
- Department of Pharmaceutical Sciences, College of Pharmacy and Pharmaceutical Sciences, Washington State University, Spokane, WA 99202, USA
| | - Hui Zhang
- Department of Pharmaceutical Sciences, College of Pharmacy and Pharmaceutical Sciences, Washington State University, Spokane, WA 99202, USA
| | - Christopher J. Davis
- Department of Translational Medicine and Physiology, Elson S. Floyd College of Medicine, Washington State University, Spokane, WA 99202, USA
| | - Gavin P. Robertson
- Department of Pharmacology, Pathology, Dermatology, and Surgery, Pennsylvania State University College of Medicine, Hershey, PA 17033, USA
| | - Jiyue Zhu
- Department of Pharmaceutical Sciences, College of Pharmacy and Pharmaceutical Sciences, Washington State University, Spokane, WA 99202, USA
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4
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Quinn KM, Vicencio DM, La Gruta NL. The paradox of aging: Aging-related shifts in T cell function and metabolism. Semin Immunol 2023; 70:101834. [PMID: 37659169 DOI: 10.1016/j.smim.2023.101834] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/13/2023] [Revised: 08/17/2023] [Accepted: 08/17/2023] [Indexed: 09/04/2023]
Abstract
T cell survival, differentiation after stimulation, and function are intrinsically linked to distinct cellular metabolic states. The ability of T cells to readily transition between metabolic states enables flexibility to meet the changing energy demands defined by distinct effector states or T cell lineages. Immune aging is characterized, in part, by the loss of naïve T cells, accumulation of senescent T cells, severe dysfunction in memory phenotype T cells in particular, and elevated levels of inflammatory cytokines, or 'inflammaging'. Here, we review our current understanding of the phenotypic and functional changes that occur with aging in T cells, and how they relate to metabolic changes in the steady state and after T cell activation. We discuss the apparent contradictions in the aging T cell phenotype - where enhanced differentiation states and metabolic profiles in the steady state can correspond to a diminished capacity to adapt metabolically and functionally after T cell activation. Finally, we discuss key recent studies that indicate the enormous potential for aged T cell metabolism to induce systemic inflammaging and organism-wide multimorbidity, resulting in premature death.
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Affiliation(s)
- Kylie M Quinn
- School of Health and Biomedical Sciences, Royal Melbourne Institute of Technology University, Bundoora, Victoria, Australia; Immunity Program and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
| | - Daniela M Vicencio
- Immunity Program and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia; Division of Biomedical Sciences, Warwick Medical School, The University of Warwick, Coventry, UK
| | - Nicole L La Gruta
- Immunity Program and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia.
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5
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Lathe R, St Clair D. Programmed ageing: decline of stem cell renewal, immunosenescence, and Alzheimer's disease. Biol Rev Camb Philos Soc 2023. [PMID: 37068798 DOI: 10.1111/brv.12959] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Revised: 03/27/2023] [Accepted: 03/30/2023] [Indexed: 04/19/2023]
Abstract
The characteristic maximum lifespan varies enormously across animal species from a few hours to hundreds of years. This argues that maximum lifespan, and the ageing process that itself dictates lifespan, are to a large extent genetically determined. Although controversial, this is supported by firm evidence that semelparous species display evolutionarily programmed ageing in response to reproductive and environmental cues. Parabiosis experiments reveal that ageing is orchestrated systemically through the circulation, accompanied by programmed changes in hormone levels across a lifetime. This implies that, like the circadian and circannual clocks, there is a master 'clock of age' (circavital clock) located in the limbic brain of mammals that modulates systemic changes in growth factor and hormone secretion over the lifespan, as well as systemic alterations in gene expression as revealed by genomic methylation analysis. Studies on accelerated ageing in mice, as well as human longevity genes, converge on evolutionarily conserved fibroblast growth factors (FGFs) and their receptors, including KLOTHO, as well as insulin-like growth factors (IGFs) and steroid hormones, as key players mediating the systemic effects of ageing. Age-related changes in these and multiple other factors are inferred to cause a progressive decline in tissue maintenance through failure of stem cell replenishment. This most severely affects the immune system, which requires constant renewal from bone marrow stem cells. Age-related immune decline increases risk of infection whereas lifespan can be extended in germfree animals. This and other evidence suggests that infection is the major cause of death in higher organisms. Immune decline is also associated with age-related diseases. Taking the example of Alzheimer's disease (AD), we assess the evidence that AD is caused by immunosenescence and infection. The signature protein of AD brain, Aβ, is now known to be an antimicrobial peptide, and Aβ deposits in AD brain may be a response to infection rather than a cause of disease. Because some cognitively normal elderly individuals show extensive neuropathology, we argue that the location of the pathology is crucial - specifically, lesions to limbic brain are likely to accentuate immunosenescence, and could thus underlie a vicious cycle of accelerated immune decline and microbial proliferation that culminates in AD. This general model may extend to other age-related diseases, and we propose a general paradigm of organismal senescence in which declining stem cell proliferation leads to programmed immunosenescence and mortality.
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Affiliation(s)
- Richard Lathe
- Division of Infection Medicine, Chancellor's Building, University of Edinburgh Medical School, Little France, Edinburgh, EH16 4SB, UK
| | - David St Clair
- Institute of Medical Sciences, School of Medicine, University of Aberdeen, Aberdeen, AB25 2ZD, UK
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6
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Yu X, Liu MM, Zheng CY, Liu YT, Wang Z, Wang ZY. Telomerase reverse transcriptase and neurodegenerative diseases. Front Immunol 2023; 14:1165632. [PMID: 37063844 PMCID: PMC10091515 DOI: 10.3389/fimmu.2023.1165632] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2023] [Accepted: 03/15/2023] [Indexed: 03/31/2023] Open
Abstract
Neurodegenerative diseases (NDs) are chronic conditions that result in progressive damage to the nervous system, including Alzheimer’s disease (AD), Parkinson’s disease (PD), Huntington’s disease (HD), and Amyotrophic lateral sclerosis (ALS). Age is a major risk factor for NDs. Telomere shortening is a biological marker of cellular aging, and telomerase reverse transcriptase (TERT) has been shown to slow down this process by maintaining telomere length. The blood-brain barrier (BBB) makes the brain a unique immune organ, and while the number of T cells present in the central nervous system is limited, they play an important role in NDs. Research suggests that NDs can be influenced by modulating peripheral T cell immune responses, and that TERT may play a significant role in T cell senescence and NDs. This review focuses on the current state of research on TERT in NDs and explores the potential connections between TERT, T cells, and NDs. Further studies on aging and telomeres may provide valuable insights for developing therapeutic strategies for age-related diseases.
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7
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Post-Transcriptional and Post-Translational Modifications in Telomerase Biogenesis and Recruitment to Telomeres. Int J Mol Sci 2023; 24:ijms24055027. [PMID: 36902458 PMCID: PMC10003056 DOI: 10.3390/ijms24055027] [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: 02/02/2023] [Revised: 03/02/2023] [Accepted: 03/03/2023] [Indexed: 03/08/2023] Open
Abstract
Telomere length is associated with the proliferative potential of cells. Telomerase is an enzyme that elongates telomeres throughout the entire lifespan of an organism in stem cells, germ cells, and cells of constantly renewed tissues. It is activated during cellular division, including regeneration and immune responses. The biogenesis of telomerase components and their assembly and functional localization to the telomere is a complex system regulated at multiple levels, where each step must be tuned to the cellular requirements. Any defect in the function or localization of the components of the telomerase biogenesis and functional system will affect the maintenance of telomere length, which is critical to the processes of regeneration, immune response, embryonic development, and cancer progression. An understanding of the regulatory mechanisms of telomerase biogenesis and activity is necessary for the development of approaches toward manipulating telomerase to influence these processes. The present review focuses on the molecular mechanisms involved in the major steps of telomerase regulation and the role of post-transcriptional and post-translational modifications in telomerase biogenesis and function in yeast and vertebrates.
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8
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Functional T cells are capable of supernumerary cell division and longevity. Nature 2023; 614:762-766. [PMID: 36653453 DOI: 10.1038/s41586-022-05626-9] [Citation(s) in RCA: 61] [Impact Index Per Article: 61.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2022] [Accepted: 12/05/2022] [Indexed: 01/20/2023]
Abstract
Differentiated somatic mammalian cells putatively exhibit species-specific division limits that impede cancer but may constrain lifespans1-3. To provide immunity, transiently stimulated CD8+ T cells undergo unusually rapid bursts of numerous cell divisions, and then form quiescent long-lived memory cells that remain poised to reproliferate following subsequent immunological challenges. Here we addressed whether T cells are intrinsically constrained by chronological or cell-division limits. We activated mouse T cells in vivo using acute heterologous prime-boost-boost vaccinations4, transferred expanded cells to new mice, and then repeated this process iteratively. Over 10 years (greatly exceeding the mouse lifespan)5 and 51 successive immunizations, T cells remained competent to respond to vaccination. Cells required sufficient rest between stimulation events. Despite demonstrating the potential to expand the starting population at least 1040-fold, cells did not show loss of proliferation control and results were not due to contamination with young cells. Persistent stimulation by chronic infections or cancer can cause T cell proliferative senescence, functional exhaustion and death6. We found that although iterative acute stimulations also induced sustained expression and epigenetic remodelling of common exhaustion markers (including PD1, which is also known as PDCD1, and TOX) in the cells, they could still proliferate, execute antimicrobial functions and form quiescent memory cells. These observations provide a model to better understand memory cell differentiation, exhaustion, cancer and ageing, and show that functionally competent T cells can retain the potential for extraordinary population expansion and longevity well beyond their organismal lifespan.
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9
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Dizaji Asl K, Rafat A, Movassaghpour AA, Nozad Charoudeh H, Tayefi Nasrabadi H. The Effect of Telomerase Inhibition on NK Cell Activity in Acute Myeloid Leukemia. Adv Pharm Bull 2023; 13:170-175. [PMID: 36721807 PMCID: PMC9871272 DOI: 10.34172/apb.2023.018] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2021] [Revised: 09/20/2021] [Accepted: 09/28/2021] [Indexed: 02/03/2023] Open
Abstract
Purpose: Acute myeloid leukemia (AML) is known to be an invasive and highly lethal hematological malignancy in adults and children. Resistance to the present treatments, including radiotherapy and chemotherapy with their side effects and telomere length shortening are the main cause of the mortality in AML patients. Telomeres sequence which are located at the end of eukaryotic chromosome play pivotal role in genomic stability. Recent studies have shown that apoptosis process is blocked in AML patient by the excessive telomerase activity in cancerous blasts. Therefore, the find of effective ways to prevent disease progression has been considered by the researchers. Natural killer (NK) cells as granular effector cells play a critical role in elimination of abnormal and tumor cells. Given that the cytotoxic function of NK cells is disrupted in the AML patients, we investigated the effect of telomerase inhibitors on NK cell differentiation. Methods: To evaluate telomerase inhibition on NK cell differentiation, the expression of CD105, CD56, CD57, and KIRs was evaluated in CD34+ derived NK cells after incubation of them with BIBR1532. Results: The results showed that the expression of CD105, CD56, CD57, and KIRs receptors reduces after telomerase inhibition. According to these findings, BIBR1532 affected the final differentiation of NK cells. Conclusion: The results revealed that telomerase inhibitor drugs suppress cancer cell progression in a NK cells-independent process.
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Affiliation(s)
- Khadijeh Dizaji Asl
- Student Research Committee, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Ali Rafat
- Student Research Committee, Tabriz University of Medical Sciences, Tabriz, Iran.,Department of Anatomical Sciences, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Ali Akbar Movassaghpour
- Hematology and Oncology Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Hojjatollah Nozad Charoudeh
- Department of Anatomical Sciences, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran.,Stem Cell Research Centre, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Hamid Tayefi Nasrabadi
- Department of Anatomical Sciences, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran.,Corresponding Author: Hamid Tayefi Nasrabadi,
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10
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Booth LK, Redgrave RE, Tual-Chalot S, Spyridopoulos I, Phillips HM, Richardson GD. Heart Disease and Ageing: The Roles of Senescence, Mitochondria, and Telomerase in Cardiovascular Disease. Subcell Biochem 2023; 103:45-78. [PMID: 37120464 DOI: 10.1007/978-3-031-26576-1_4] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/01/2023]
Abstract
During ageing molecular damage leads to the accumulation of several hallmarks of ageing including mitochondrial dysfunction, cellular senescence, genetic instability and chronic inflammation, which contribute to the development and progression of ageing-associated diseases including cardiovascular disease. Consequently, understanding how these hallmarks of biological ageing interact with the cardiovascular system and each other is fundamental to the pursuit of improving cardiovascular health globally. This review provides an overview of our current understanding of how candidate hallmarks contribute to cardiovascular diseases such as atherosclerosis, coronary artery disease and subsequent myocardial infarction, and age-related heart failure. Further, we consider the evidence that, even in the absence of chronological age, acute cellular stress leading to accelerated biological ageing expedites cardiovascular dysfunction and impacts on cardiovascular health. Finally, we consider the opportunities that modulating hallmarks of ageing offer for the development of novel cardiovascular therapeutics.
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Affiliation(s)
- Laura K Booth
- Translational and Clinical Research Institute, Vascular Biology and Medicine Theme, Newcastle University, Newcastle upon Tyne, UK
| | - Rachael E Redgrave
- Biosciences Institute, Vascular Biology and Medicine Theme, Newcastle University, Newcastle upon Tyne, UK
| | - Simon Tual-Chalot
- Biosciences Institute, Vascular Biology and Medicine Theme, Newcastle University, Newcastle upon Tyne, UK
| | - Ioakim Spyridopoulos
- Translational and Clinical Research Institute, Vascular Biology and Medicine Theme, Newcastle University, Newcastle upon Tyne, UK
| | - Helen M Phillips
- Biosciences Institute, Vascular Biology and Medicine Theme, Newcastle University, Newcastle upon Tyne, UK
| | - Gavin D Richardson
- Biosciences Institute, Vascular Biology and Medicine Theme, Newcastle University, Newcastle upon Tyne, UK.
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11
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Rodríguez-Centeno J, Esteban-Cantos A, Montejano R, Stella-Ascariz N, De Miguel R, Mena-Garay B, Saiz-Medrano G, Alejos B, Jiménez-González M, Bernardino JI, Cadiñanos J, Castro-Alvarez JM, Rodés B, Arribas JR. Effects of tenofovir on telomeres, telomerase and T cell maturational subset distribution in long-term aviraemic HIV-infected adults. J Antimicrob Chemother 2022; 77:1125-1132. [PMID: 35045162 DOI: 10.1093/jac/dkab492] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2021] [Accepted: 12/07/2021] [Indexed: 11/13/2022] Open
Abstract
OBJECTIVES To evaluate whether the negative impact of tenofovir on telomere length (TL) is due to immune reconstitution interference or inhibition of telomerase. METHODS One hundred and twenty-eight long-term aviraemic HIV adults treated with tenofovir-containing (n = 79) or tenofovir-sparing regimens (n = 49) were recruited to compare the following: TL in whole blood, PBMCs, CD4+ T cells and CD8+ T cells by quantitative PCR (qPCR); telomerase activity in PBMCs, CD4+ cells and CD8+ T cells using the TRAPeze RT Telomerase Detection Kit; and T cell maturational subset distribution by flow cytometry. RESULTS In an adjusted analysis, participants treated with tenofovir for at least 4 years had shorter TL in CD8+ T cells (P = 0.04) and lower telomerase activity in CD4+ (P = 0.012) and CD8+ T cells (P = 0.023). Tenofovir treatment was also associated with lower proportions of recent thymic emigrant (RTE) CD4+ cells (P = 0.031) and PD1 marker expression (P = 0.013). CONCLUSIONS In long-term aviraemic HIV adults, the inhibition of telomerase by tenofovir could explain telomere shortening in CD8+ T cells. There is no telomere shortening in the CD4+ compartment and the decrease in telomerase activity could be explained both by the inhibition by tenofovir and by the lower proportion of RTE CD4+cells.
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Affiliation(s)
| | | | - Rocío Montejano
- Institute for Health Research Hospital La Paz (IdiPAZ), Madrid, Spain.,Internal Medicine Department, La Paz University Hospital, Madrid, Spain
| | | | - Rosa De Miguel
- Institute for Health Research Hospital La Paz (IdiPAZ), Madrid, Spain.,Internal Medicine Department, La Paz University Hospital, Madrid, Spain
| | | | | | | | | | - Jose I Bernardino
- Institute for Health Research Hospital La Paz (IdiPAZ), Madrid, Spain.,Internal Medicine Department, La Paz University Hospital, Madrid, Spain
| | - Julen Cadiñanos
- Institute for Health Research Hospital La Paz (IdiPAZ), Madrid, Spain.,Internal Medicine Department, La Paz University Hospital, Madrid, Spain
| | - Juan M Castro-Alvarez
- Institute for Health Research Hospital La Paz (IdiPAZ), Madrid, Spain.,Internal Medicine Department, La Paz University Hospital, Madrid, Spain
| | - Berta Rodés
- Institute for Health Research Hospital La Paz (IdiPAZ), Madrid, Spain
| | - Jose R Arribas
- Institute for Health Research Hospital La Paz (IdiPAZ), Madrid, Spain.,Internal Medicine Department, La Paz University Hospital, Madrid, Spain.,CIBER de Enfermedades Infecciosas
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12
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Ovarian Telomerase and Female Fertility. Biomedicines 2021; 9:biomedicines9070842. [PMID: 34356906 PMCID: PMC8301802 DOI: 10.3390/biomedicines9070842] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2021] [Revised: 07/08/2021] [Accepted: 07/14/2021] [Indexed: 11/16/2022] Open
Abstract
Women's fertility is characterized both quantitatively and qualitatively mainly by the pool of ovarian follicles. Monthly, gonadotropins cause an intense multiplication of granulosa cells surrounding the oocyte. This step of follicular development requires a high proliferation ability for these cells. Telomere length plays a crucial role in the mitotic index of human cells. Hence, disrupting telomere homeostasis could directly affect women's fertility. Strongly expressed in ovaries, telomerase is the most effective factor to limit telomeric attrition and preserve ovarian reserve. Considering these facts, two situations of infertility could be correlated with the length of telomeres and ovarian telomerase activity: PolyCystic Ovary Syndrome (PCOS), which is associated with a high density of small antral follicles, and Premature Ovarian Failure (POF), which is associated with a premature decrease in ovarian reserve. Several authors have studied this topic, expecting to find long telomeres and strong telomerase activity in PCOS and short telomeres and low telomerase activity in POF patients. Although the results of these studies are contradictory, telomere length and the ovarian telomerase impact in women's fertility disorders appear obvious. In this context, our research perspectives aimed to explore the stimulation of ovarian telomerase to limit the decrease in the follicular pool while avoiding an increase in cancer risk.
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13
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Senescence and senolytics in cardiovascular disease: Promise and potential pitfalls. Mech Ageing Dev 2021; 198:111540. [PMID: 34237321 PMCID: PMC8387860 DOI: 10.1016/j.mad.2021.111540] [Citation(s) in RCA: 57] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2021] [Revised: 06/28/2021] [Accepted: 07/04/2021] [Indexed: 02/08/2023]
Abstract
Ageing is the biggest risk factor for impaired cardiovascular health, with cardiovascular disease being the cause of death in 40 % of individuals over 65 years old. Ageing is associated with an increased prevalence of atherosclerosis, coronary artery stenosis and subsequent myocardial infarction, thoracic aortic aneurysm, valvular heart disease and heart failure. An accumulation of senescence and increased inflammation, caused by the senescence-associated secretory phenotype, have been implicated in the aetiology and progression of these age-associated diseases. Recently it has been demonstrated that compounds targeting components of anti-apoptotic pathways expressed by senescent cells can preferentially induce senescence cells to apoptosis and have been termed senolytics. In this review, we discuss the evidence demonstrating that senescence contributes to cardiovascular disease, with a particular focus on studies that indicate the promise of senotherapy. Based on these data we suggest novel indications for senolytics as a treatment of cardiovascular diseases which have yet to be studied in the context of senotherapy. Finally, while the potential benefits are encouraging, several complications may result from senolytic treatment. We, therefore, consider these challenges in the context of the cardiovascular system.
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14
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Plyasova AA, Zhdanov DD. Alternative Splicing of Human Telomerase Reverse Transcriptase (hTERT) and Its Implications in Physiological and Pathological Processes. Biomedicines 2021; 9:526. [PMID: 34065134 PMCID: PMC8150890 DOI: 10.3390/biomedicines9050526] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2021] [Revised: 05/03/2021] [Accepted: 05/05/2021] [Indexed: 12/24/2022] Open
Abstract
Alternative splicing (AS) of human telomerase catalytic subunit (hTERT, human telomerase reverse transcriptase) pre-mRNA strongly regulates telomerase activity. Several proteins can regulate AS in a cell type-specific manner and determine the functions of cells. In addition to being involved in telomerase activity regulation, AS provides cells with different splice variants that may have alternative biological activities. The modulation of telomerase activity through the induction of hTERT AS is involved in the development of different cancer types and embryos, and the differentiation of stem cells. Regulatory T cells may suppress the proliferation of target human and murine T and B lymphocytes and NK cells in a contact-independent manner involving activation of TERT AS. This review focuses on the mechanism of regulation of hTERT pre-mRNA AS and the involvement of splice variants in physiological and pathological processes.
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Affiliation(s)
| | - Dmitry D. Zhdanov
- Institute of Biomedical Chemistry, Pogodinskaya st 10/8, 119121 Moscow, Russia;
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15
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Mizuguchi M, Hara T, Yoshita-Takahashi M, Kohda T, Tanaka Y, Nakamura M. Promoter CpG methylation inhibits Krüppel-like factor 2 (KLF2)-Mediated repression of hTERT gene expression in human T-cells. Biochem Biophys Rep 2021; 26:100984. [PMID: 33768169 PMCID: PMC7980061 DOI: 10.1016/j.bbrep.2021.100984] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2021] [Revised: 03/02/2021] [Accepted: 03/08/2021] [Indexed: 12/31/2022] Open
Abstract
Constitutive expression of human telomerase reverse transcriptase (hTERT) with DNA methylation of its promoter is a common phenomenon in tumor cells. We recently found that the transcriptional factor Krüppel-like factor 2 (KLF2) binds to the CpG sequences in the hTERT promoter and inhibits hTERT gene expression in normal resting T-cells. The human T-cell line Kit 225 in the resting phase induced by the deprivation of interleukin (IL)-2 showed no decrease in the expression of hTERT, despite the high expression of KLF2. To elucidate the mechanisms of deregulation of hTERT expression in T-cells, we examined the relationship between DNA methylation and KLF2 binding to the hTERT promoter. The hTERT promoter was methylated in Kit 225 cells, resulting in the inhibition of the binding of KLF2 to the promoter. DNA demethylation by the reagent Zebularine recovered KLF2 binding to the hTERT promoter, followed by the downregulation of its gene expression. These findings indicate that the repressive effect of KLF2 on hTERT gene expression is abolished by DNA methylation in T-cell lines. Unlike normal T-cells, the hTERT promoter is highly methylated in a leukemic T-cell line. DNA methylation of the promoter induces hTERT gene expression. Association between the promoter and the repressor KLF2 is inhibited by DNA methylation. Demethylation promotes binding of KLF2 and silencing of hTERT expression.
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Affiliation(s)
- Mariko Mizuguchi
- Human Gene Sciences Center, Tokyo Medical and Dental University (TMDU), Tokyo, 113-8510, Japan
- Department of Immunology, Graduate School of Medicine, University of the Ryukyus, Okinawa, 903-0215, Japan
| | - Toshifumi Hara
- Department of Medical Biochemistry, School of Pharmacy, Aichi Gakuin University, Aichi, 464-8650, Japan
| | | | - Takashi Kohda
- Department of Epigenetics, Medical Research Institute, Tokyo Medical and Dental University (TMDU), Tokyo, 113-8510, Japan
- Faculty of Life and Environmental Sciences, University of Yamanashi, Yamanashi, 400-8510, Japan
| | - Yuetsu Tanaka
- Department of Immunology, Graduate School of Medicine, University of the Ryukyus, Okinawa, 903-0215, Japan
| | - Masataka Nakamura
- Human Gene Sciences Center, Tokyo Medical and Dental University (TMDU), Tokyo, 113-8510, Japan
- Corresponding author.
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16
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Emerging Molecular Connections between NM23 Proteins, Telomeres and Telomere-Associated Factors: Implications in Cancer Metastasis and Ageing. Int J Mol Sci 2021; 22:ijms22073457. [PMID: 33801585 PMCID: PMC8036570 DOI: 10.3390/ijms22073457] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2021] [Revised: 02/15/2021] [Accepted: 02/17/2021] [Indexed: 11/20/2022] Open
Abstract
The metastasis suppressor function of NM23 proteins is widely understood. Multiple enzymatic activities of NM23 proteins have also been identified. However, relatively less known interesting aspects are being revealed from recent developments that corroborate the telomeric interactions of NM23 proteins. Telomeres are known to regulate essential physiological events such as metastasis, ageing, and cellular differentiation via inter-connected signalling pathways. Here, we review the literature on the association of NM23 proteins with telomeres or telomere-related factors, and discuss the potential implications of emerging telomeric functions of NM23 proteins. Further understanding of these aspects might be instrumental in better understanding the metastasis suppressor functions of NM23 proteins.
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17
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Powter B, Jeffreys SA, Sareen H, Cooper A, Brungs D, Po J, Roberts T, Koh ES, Scott KF, Sajinovic M, Vessey JY, de Souza P, Becker TM. Human TERT promoter mutations as a prognostic biomarker in glioma. J Cancer Res Clin Oncol 2021; 147:1007-1017. [PMID: 33547950 PMCID: PMC7954705 DOI: 10.1007/s00432-021-03536-3] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2020] [Accepted: 01/15/2021] [Indexed: 12/27/2022]
Abstract
The TERT promoter (pTERT) mutations, C228T and C250T, play a significant role in malignant transformation by telomerase activation, oncogenesis and immortalisation of cells. C228T and C250T are emerging as important biomarkers in many cancers including glioblastoma multiforme (GBM), where the prevalence of these mutations is as high as 80%. Additionally, the rs2853669 single nucleotide polymorphism (SNP) may cooperate with these pTERT mutations in modulating progression and overall survival in GBM. Using liquid biopsies, pTERT mutations, C228T and C250T, and other clinically relevant biomarkers can be easily detected with high precision and sensitivity, facilitating longitudinal analysis throughout therapy and aid in cancer patient management. In this review, we explore the potential for pTERT mutation analysis, via liquid biopsy, for its potential use in personalised cancer therapy. We evaluate the relationship between pTERT mutations and other biomarkers as well as their potential clinical utility in early detection, prognostication, monitoring of cancer progress, with the main focus being on brain cancer.
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Affiliation(s)
- Branka Powter
- Centre for Circulating Tumour Cell Diagnostics and Research, Ingham Institute for Applied Medical Research, 1 Campbell St, Liverpool, NSW, 2170, Australia.
| | - Sarah A Jeffreys
- Centre for Circulating Tumour Cell Diagnostics and Research, Ingham Institute for Applied Medical Research, 1 Campbell St, Liverpool, NSW, 2170, Australia.,School of Medicine, Western Sydney University, Campbelltown, NSW, 2560, Australia
| | - Heena Sareen
- Centre for Circulating Tumour Cell Diagnostics and Research, Ingham Institute for Applied Medical Research, 1 Campbell St, Liverpool, NSW, 2170, Australia.,Western Clinical School, University of New South Wales South, Goulburn St, Liverpool, NSW, 2170, Australia
| | - Adam Cooper
- Centre for Circulating Tumour Cell Diagnostics and Research, Ingham Institute for Applied Medical Research, 1 Campbell St, Liverpool, NSW, 2170, Australia.,School of Medicine, Western Sydney University, Campbelltown, NSW, 2560, Australia.,Cancer Therapy Centre, Liverpool Hospital, Elizabeth St and Goulburn St, Liverpool, NSW, 2170, Australia
| | - Daniel Brungs
- Centre for Circulating Tumour Cell Diagnostics and Research, Ingham Institute for Applied Medical Research, 1 Campbell St, Liverpool, NSW, 2170, Australia.,School of Medicine, University of Wollongong, Wollongong, NSW, 2522, Australia
| | - Joseph Po
- Centre for Circulating Tumour Cell Diagnostics and Research, Ingham Institute for Applied Medical Research, 1 Campbell St, Liverpool, NSW, 2170, Australia
| | - Tara Roberts
- School of Medicine, Western Sydney University, Campbelltown, NSW, 2560, Australia.,Western Clinical School, University of New South Wales South, Goulburn St, Liverpool, NSW, 2170, Australia
| | - Eng-Siew Koh
- Western Clinical School, University of New South Wales South, Goulburn St, Liverpool, NSW, 2170, Australia.,Cancer Therapy Centre, Liverpool Hospital, Elizabeth St and Goulburn St, Liverpool, NSW, 2170, Australia
| | - Kieran F Scott
- Centre for Circulating Tumour Cell Diagnostics and Research, Ingham Institute for Applied Medical Research, 1 Campbell St, Liverpool, NSW, 2170, Australia.,School of Medicine, Western Sydney University, Campbelltown, NSW, 2560, Australia
| | - Mila Sajinovic
- Centre for Circulating Tumour Cell Diagnostics and Research, Ingham Institute for Applied Medical Research, 1 Campbell St, Liverpool, NSW, 2170, Australia
| | - Joey Y Vessey
- Cancer Therapy Centre, Liverpool Hospital, Elizabeth St and Goulburn St, Liverpool, NSW, 2170, Australia
| | - Paul de Souza
- Centre for Circulating Tumour Cell Diagnostics and Research, Ingham Institute for Applied Medical Research, 1 Campbell St, Liverpool, NSW, 2170, Australia.,School of Medicine, Western Sydney University, Campbelltown, NSW, 2560, Australia.,Western Clinical School, University of New South Wales South, Goulburn St, Liverpool, NSW, 2170, Australia.,Cancer Therapy Centre, Liverpool Hospital, Elizabeth St and Goulburn St, Liverpool, NSW, 2170, Australia.,School of Medicine, University of Wollongong, Wollongong, NSW, 2522, Australia
| | - Therese M Becker
- Centre for Circulating Tumour Cell Diagnostics and Research, Ingham Institute for Applied Medical Research, 1 Campbell St, Liverpool, NSW, 2170, Australia.,School of Medicine, Western Sydney University, Campbelltown, NSW, 2560, Australia.,Western Clinical School, University of New South Wales South, Goulburn St, Liverpool, NSW, 2170, Australia
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18
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Salimi-Jeda A, Badrzadeh F, Esghaei M, Abdoli A. The role of telomerase and viruses interaction in cancer development, and telomerase-dependent therapeutic approaches. Cancer Treat Res Commun 2021; 27:100323. [PMID: 33530025 DOI: 10.1016/j.ctarc.2021.100323] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2020] [Revised: 01/19/2021] [Accepted: 01/21/2021] [Indexed: 12/21/2022]
Abstract
Human telomerase reverse transcriptase (hTERT) is an enzyme that is critically involved in elongating and maintaining telomeres length to control cell life span and replicative potential. Telomerase activity is continuously expressed in human germ-line cells and most cancer cells, whereas it is suppressed in most somatic cells. In normal cells, by reducing telomerase activity and progressively shortening the telomeres, the cells progress to the senescence or apoptosis process. However, in cancer cells, telomere lengths remain constant due to telomerase's reactivation, and cells continue to proliferate and inhibit apoptosis, and ultimately lead to cancer development and human death due to metastasis. Studies demonstrated that several DNA and RNA oncoviruses could interact with telomerase by integrating their genome sequence within the host cell telomeres specifically. Through the activation of the hTERT promoter and lengthening the telomere, these cells contributes to cancer development. Since oncoviruses can activate telomerase and increase hTERT expression, there are several therapeutic strategies based on targeting the telomerase of cancer cells like telomerase-targeted peptide vaccines, hTERT-targeting dendritic cells (DCs), hTERT-targeting gene therapy, and hTERT-targeting CRISPR/Cas9 system that can overcome tumor-mediated toleration mechanisms and specifically apoptosis in cancer cells. This study reviews available data on the molecular structure of telomerase and the role of oncoviruses and telomerase interaction in cancer development and telomerase-dependent therapeutic approaches to conquest the cancer cells.
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Affiliation(s)
- Ali Salimi-Jeda
- Department of Virology, School of Medicine, Iran University of Medical Sciences, Tehran, Iran.
| | - Fariba Badrzadeh
- Faculti of Medicine, Golestan University of Medical sciences, Golestan, Iran.
| | - Maryam Esghaei
- Department of Virology, School of Medicine, Iran University of Medical Sciences, Tehran, Iran.
| | - Asghar Abdoli
- Department of Hepatitis and AIDS, Pasteur Institute of Iran, Tehran, Iran.
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19
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Dong K, Peng X, Huang J, Xia S, Yang Y. Association of leukocyte telomere length with metabolic syndrome in type 2 diabetes mellitus. JOURNAL OF RESEARCH IN MEDICAL SCIENCES 2021; 26:43. [PMID: 34484375 PMCID: PMC8384009 DOI: 10.4103/jrms.jrms_793_20] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/16/2020] [Revised: 10/06/2020] [Accepted: 02/10/2021] [Indexed: 11/18/2022]
Abstract
Background: Leukocyte telomere length (LTL) has been revealed to be associated with aging-related diseases such as metabolic syndrome (MetS) and Type 2 diabetes mellitus (T2DM). We aimed to investigate the correlation of LTL with MetS and its components in T2DM patients in this cross-sectional study. Materials and Methods: A total of 344 T2DM patients were enrolled into this study. LTL was measured by Southern blot-based terminal restriction fragment length analysis. MetS was clinically defined by 2007 Chinese Guidelines on Prevention and Treatment of Dyslipidemia in Adults. Results: Of 344 T2DM patients, 53% had MetS. T2DM patients with MetS had significantly longer LTL than those without MetS (6451.95 ± 51.10 base pairs vs. 6076.13 ± 55.13 base pairs, P < 0.001), especially when T2DM patients had poor glycemic control (hemoglobin A1c ≥7%). Meanwhile, the trend of longer LTL was associated with the increased components of MetS in T2DM patient. Finally, LTL had a significant association with MetS (odds ratio [OR]: 2.096, 95% confidence interval [CI] 1.337–3.285, P = 0.001), low levels of high-density lipoprotein-cholesterol (HDL-C) (OR: 2.412, 95% CI 1.350–4.308, P = 0.003) in T2DM patients. Conclusion: T2DM patients with MetS had a significantly longer LTL than those without MetS. The longer LTL was especially evident in T2DM patients with poor glycemic control. Longer LTL was positively associated with MetS, particularly low levels of HDL-C in T2DM patients.
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20
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Dookun E, Passos JF, Arthur HM, Richardson GD. Therapeutic Potential of Senolytics in Cardiovascular Disease. Cardiovasc Drugs Ther 2020; 36:187-196. [PMID: 32979174 PMCID: PMC8770386 DOI: 10.1007/s10557-020-07075-w] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 09/03/2020] [Indexed: 02/07/2023]
Abstract
Ageing is the biggest risk factor for impaired cardiovascular health, with cardiovascular disease being the leading cause of death in 40% of individuals over 65 years old. Ageing is associated with both an increased prevalence of cardiovascular disease including heart failure, coronary artery disease, and myocardial infarction. Furthermore, ageing is associated with a poorer prognosis to these diseases. Genetic models allowing the elimination of senescent cells revealed that an accumulation of senescence contributes to the pathophysiology of cardiovascular ageing and promotes the progression of cardiovascular disease through the expression of a proinflammatory and profibrotic senescence-associated secretory phenotype. These studies have resulted in an effort to identify pharmacological therapeutics that enable the specific elimination of senescent cells through apoptosis induction. These senescent cell apoptosis-inducing compounds are termed senolytics and their potential to ameliorate age-associated cardiovascular disease is the focus of this review.
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Affiliation(s)
- Emily Dookun
- Biosciences Institute, Newcastle University, Newcastle upon Tyne, NE1 3BZ, UK
| | - João F Passos
- Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, MN, USA
| | - Helen M Arthur
- Biosciences Institute, Newcastle University, Newcastle upon Tyne, NE1 3BZ, UK
| | - Gavin D Richardson
- Biosciences Institute, Newcastle University, Newcastle upon Tyne, NE1 3BZ, UK.
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21
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Lustig A, Manor T, Shi G, Li J, Wang YT, An Y, Liu YT, Weng NP. Lipid Microbubble-Conjugated Anti-CD3 and Anti-CD28 Antibodies (Microbubble-Based Human T Cell Activator) Offer Superior Long-Term Expansion of Human Naive T Cells In Vitro. Immunohorizons 2020; 4:475-484. [PMID: 32769179 PMCID: PMC10433792 DOI: 10.4049/immunohorizons.2000056] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2020] [Accepted: 07/21/2020] [Indexed: 11/19/2022] Open
Abstract
Stimulation of human primary T cells with immobilized anti-CD3 and anti-CD28 Abs in vitro provide a system to study T cell activation and proliferation and an avenue for expanding T cells for immunotherapy. Magnetic beads conjugated with anti-CD3 and anti-CD28 Abs (Dynabeads Human T-Activator [D-TCA]) have been a golden standard for stimulating human primary T cells in vitro. In this study, we report that an application using anti-CD3 and anti-CD28 Abs conjugated on lipid microbubbles (microbubble-based human T cell activator [MB-TCA]) to stimulate primary human naive T cells resulted in expansion superior to D-TCA. In 56-d cultures with three repeated stimulation cycles (14 d per stimulation), we found that 1) MB-TCA induced significantly better expansion (20- and 10-fold increase) of naive CD4+ and CD8+ T cells than did D-TCA; 2) MB-TCA- and D-TCA-stimulated T cells had a similar number of initial cell divisions, but MB-TCA had significantly lower activation-induced cell death than D-TCA; 3) MB-TCA-stimulated T cells produced less TNF-α than did D-TCA; and 4) blocking TNF-α action via adding an Ab against TNF-αR (TNFRSF1A) significantly improved expansion of T cells activated by D-TCA in vitro. Together, we demonstrated that the MB-TCA induces a better expansion of human naive T cells in vitro and offers advantages in both basic and clinical applications in which the outcome depends on the number of T cells.
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Affiliation(s)
- Ana Lustig
- Laboratory of Molecular Biology and Immunology, National Institute on Aging, National Institutes of Health, Baltimore, MD 21224
| | - Ty'Keemi Manor
- Laboratory of Molecular Biology and Immunology, National Institute on Aging, National Institutes of Health, Baltimore, MD 21224
| | | | - Jiangyuan Li
- Laboratory of Molecular Biology and Immunology, National Institute on Aging, National Institutes of Health, Baltimore, MD 21224
| | | | - Yang An
- Laboratory of Behavioral Neuroscience, National Institute on Aging, National Institutes of Health, Baltimore, MD 21224; and
| | - Yu-Tsueng Liu
- University of California, San Diego, San Diego, CA 92093
| | - Nan-Ping Weng
- Laboratory of Molecular Biology and Immunology, National Institute on Aging, National Institutes of Health, Baltimore, MD 21224;
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22
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Wang C, Wolters PJ, Calfee CS, Liu S, Balmes JR, Zhao Z, Koyama T, Ware LB. Long-term ozone exposure is positively associated with telomere length in critically ill patients. ENVIRONMENT INTERNATIONAL 2020; 141:105780. [PMID: 32417614 PMCID: PMC7535086 DOI: 10.1016/j.envint.2020.105780] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/14/2020] [Revised: 04/13/2020] [Accepted: 04/30/2020] [Indexed: 05/14/2023]
Abstract
RATIONALE Chronic air pollutant exposure has been associated with development of Acute Respiratory Distress Syndrome (ARDS) in patients at risk, particularly from severe trauma. We recently reported that shorter peripheral blood leukocyte (PBL) telomere length (TL) was associated with worse outcomes and higher severity of ARDS in critically ill patients. Since most major air pollutants are potent oxidants that can induce cellular oxidative stress, and oxidative stress can accelerate telomere shortening, we hypothesized that higher levels of chronic air pollutant exposure would be associated with shorter telomere length in critically ill patients including patients with ARDS. METHODS PBL-TL was measured in genomic DNA collected on the morning of ICU day 2 in 772 critically ill patients enrolled in a prospective observational study. Exposures to air pollutants including ozone (warm-season only), particulate matter < 2.5 µm (PM2.5), particulate matter < 10 µm (PM10), CO, NO2 and SO2, were estimated by weighted average of daily levels from all monitors within 50 km of each patient's residential address for the 3 years prior to admission. Associations of each air pollutant exposure and PBL-TL were investigated by multivariable linear regression models adjusting for age, ethnicity, sex, smoking history, alcohol abuse, insurance status, median household income, history of malignancy and APACHE II. RESULTS Contrary to our hypothesis, TL increased across exposure quartiles in both ozone and PM2.5 analyses (p < 0.05). In a regression model controlling for potential confounders, long term ozone exposure was significantly associated with an increase in TL in the entire cohort (0.31 kb per 10 ppb), as well as in subgroups with sepsis, trauma and ARDS (all p < 0.05). In multivariable models, entire-year exposure to PM2.5, PM10, CO, NO2 and SO2 was not associated with TL after adjustment for potential confounders. In an analysis restricted to warm-season levels to assess the effect of seasonality, higher warm-season PM2.5 and CO exposures were independently associated with longer TL. CONCLUSIONS Long-term exposure to ozone is associated with longer peripheral blood TL in critically ill patients. Further studies are needed to investigate the potential underlying mechanisms for this unexpected positive association between telomere length and air pollution exposure in critical illness.
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Affiliation(s)
- Chunxue Wang
- Division of Allergy, Pulmonary and Critical Care Medicine, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Paul J Wolters
- Department of Medicine, University of California, San Francisco, CA, USA
| | - Carolyn S Calfee
- Department of Medicine, University of California, San Francisco, CA, USA
| | - Shuo Liu
- Department of Respiratory Medicine, The Fourth Affiliated Hospital of China Medical University, Shenyang, Liaoning, People's Republic of China
| | - John R Balmes
- Department of Medicine, University of California, San Francisco, CA, USA
| | - Zhiguo Zhao
- Department of Biostatistics, Vanderbilt University, Nashville, TN, USA
| | - Tatsuki Koyama
- Department of Biostatistics, Vanderbilt University, Nashville, TN, USA
| | - Lorraine B Ware
- Division of Allergy, Pulmonary and Critical Care Medicine, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, USA; Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, TN, USA.
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23
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Human Telomerase RNA: Telomerase Component or More? Biomolecules 2020; 10:biom10060873. [PMID: 32517215 PMCID: PMC7355840 DOI: 10.3390/biom10060873] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2020] [Revised: 06/04/2020] [Accepted: 06/05/2020] [Indexed: 12/16/2022] Open
Abstract
Telomerase is a ribonucleoprotein complex that maintains the lengths of telomeres. Most studies of telomerase function have focused on the involvement of telomerase activation in the immortalization of cancer cells and cellular rejuvenation. However, some studies demonstrated that the results do not meet expectations for telomerase action in telomere maintenance. Recent results give reason to think that major telomerase components-the reverse transcriptase protein subunit and telomerase RNA-may participate in many cellular processes, including the regulation of apoptosis and autophagy, cell survival, pro-proliferative effects, regulation of gene expression, and protection against oxidative stress. However, the difficulties faced by scientist when researching telomerase component functions often reduce confidence in the minor effects observed in experiments. In this review, we focus on the analysis of the functions of telomerase components (paying more attention to the telomerase RNA component), both as a complex and as independent components, providing effects that are not associated with telomerase activity and telomere length maintenance. Despite the fact that the data on alternative roles of telomerase components look illusory, it would be wrong to completely reject the possibility of their involvement in other biological processes excluded from research/discussion. Investigations to improve the understanding of every aspect of the functioning of telomerase components will provide the basis for a more precise development of approaches to regulate cellular homeostasis, which is important for carcinogenesis and aging.
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24
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Dalzini A, Petrara MR, Ballin G, Zanchetta M, Giaquinto C, De Rossi A. Biological Aging and Immune Senescence in Children with Perinatally Acquired HIV. J Immunol Res 2020; 2020:8041616. [PMID: 32509884 PMCID: PMC7246406 DOI: 10.1155/2020/8041616] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Accepted: 04/22/2020] [Indexed: 12/12/2022] Open
Abstract
Chronic HIV-infected children suffer from premature aging and aging-related diseases. Viral replication induces an ongoing inflammation process, with the release of pathogen-associated molecular patterns (PAMPs) and damage-associated molecular patterns (DAMPs), the activation of the immune system, and the production of proinflammatory cytokines. Although combined highly active antiretroviral therapy (ART) has significantly modified the natural course of HIV infection, normalization of T and B cell phenotype is not completely achievable; thus, many HIV-infected children display several phenotypical alterations, including higher percentages of activated cells, that favor an accelerated telomere attrition, and higher percentages of exhausted and senescent cells. All these features ultimately lead to the clinical manifestations related to premature aging and comorbidities typically observed in older general population, including non-AIDS-related malignancies. Therefore, even under effective treatment, the premature aging process of HIV-infected children negatively impacts their quality and length of life. This review examines the available data on the impact of HIV and ART on immune and biological senescence of HIV-infected children.
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Affiliation(s)
- Annalisa Dalzini
- Section of Oncology and Immunology, Department of Surgery, Oncology and Gastroenterology, Unit of Viral Oncology and AIDS Reference Center, University of Padova, Padova, Italy
| | - Maria Raffaella Petrara
- Section of Oncology and Immunology, Department of Surgery, Oncology and Gastroenterology, Unit of Viral Oncology and AIDS Reference Center, University of Padova, Padova, Italy
| | - Giovanni Ballin
- Section of Oncology and Immunology, Department of Surgery, Oncology and Gastroenterology, Unit of Viral Oncology and AIDS Reference Center, University of Padova, Padova, Italy
| | | | - Carlo Giaquinto
- Department of Mother and Child Health, University of Padova, Padova, Italy
| | - Anita De Rossi
- Section of Oncology and Immunology, Department of Surgery, Oncology and Gastroenterology, Unit of Viral Oncology and AIDS Reference Center, University of Padova, Padova, Italy
- Veneto Institute of Oncology IOV – IRCCS, Padua, Italy
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25
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Attar A, Khosravi Maharlooei M, Nazarinia MA, Hosseini A, Bajalli Z, Moeini YS, Monabati A, Amirmoezi F, Jaberipour M, Habibagahi M. Expression Pattern of Telomerase Reverse Transcriptase (hTERT) Variants and Bcl-2 in Peripheral Lymphocytes of Systemic Lupus Erythematosus Patients. IRANIAN JOURNAL OF PATHOLOGY 2020; 15:225-231. [PMID: 32754218 PMCID: PMC7354072 DOI: 10.30699/ijp.2020.110994.2187] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/09/2019] [Accepted: 04/10/2020] [Indexed: 11/06/2022]
Abstract
Background & Objective: It is not clear whether activated lymphocytes of patients with systemic lupus erythematosus (SLE) are more proliferative or less apoptotic. We aimed to delineate potential differences between B and T cells of SLE patients compared to healthy controls regarding the telomerase activity and apoptosis status. Methods: In this cross-sectional case control study, Blood samples were taken from 10 SLE patients and 10 healthy controls. B and T cells were separated using magnetic cell sorting system. Telomeric repeat amplification protocol (TRAP) assay and real-time PCR were used to determine the telomerase activity and the expression of alternatively spliced variants. Results: Four patients under treatment showed significant telomerase activity in their T cells. Four of the newly diagnosed patients showed telomerase activity in their B cells (20% of all patients and 40% of new onset patients). There was no specific pattern of human telomerase reverse transcriptase variant expression within the patients’ lymphocytes. A significantly reduced expression of Bcl-2 was detected in B cells (P=0.018) and a trend toward lower Bcl-2 expression in T cells was seen in SLE patients compared to healthy controls. Conclusion: Although not definitive, our results may suggest that B cells may have more active roles during the earlier phases of the disease attack, while T cells take over when the disease reaches its chronic stages.
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Affiliation(s)
- Armin Attar
- Department of Cardiovascular Medicine, Division of Interventional Cardiology, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Mohsen Khosravi Maharlooei
- Students' Research Committee, Cell and Molecular Medicine Research Group, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Mohammad Ali Nazarinia
- Internal Medicine Department, Rheumatology Division, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Ahmad Hosseini
- Institute of Cancer Research, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Zohre Bajalli
- Students' Research Committee, Cell and Molecular Medicine Research Group, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Yalda Sadat Moeini
- Department of Anesthesiology, Division of Intensive Care Unit, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Ahmad Monabati
- Department of Pathology, Shiraz University of Medical Sciences, Shiraz, Iran.,Hematology research center, Shiraz university of medical sciences, Shiraz, Iran
| | - Fatemeh Amirmoezi
- Department of Pathology, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Mansooreh Jaberipour
- Institute of Cancer Research, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Mojtaba Habibagahi
- Department of Immunology, Shiraz University of Medical Sciences, Shiraz, Iran
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Roake CM, Artandi SE. Regulation of human telomerase in homeostasis and disease. Nat Rev Mol Cell Biol 2020; 21:384-397. [PMID: 32242127 DOI: 10.1038/s41580-020-0234-z] [Citation(s) in RCA: 163] [Impact Index Per Article: 40.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/05/2020] [Indexed: 12/14/2022]
Abstract
Telomerase is a ribonucleoprotein complex, the catalytic core of which includes the telomerase reverse transcriptase (TERT) and the non-coding human telomerase RNA (hTR), which serves as a template for the addition of telomeric repeats to chromosome ends. Telomerase expression is restricted in humans to certain cell types, and telomerase levels are tightly controlled in normal conditions. Increased levels of telomerase are found in the vast majority of human cancers, and we have recently begun to understand the mechanisms by which cancer cells increase telomerase activity. Conversely, germline mutations in telomerase-relevant genes that decrease telomerase function cause a range of genetic disorders, including dyskeratosis congenita, idiopathic pulmonary fibrosis and bone marrow failure. In this Review, we discuss the transcriptional regulation of human TERT, hTR processing, assembly of the telomerase complex, the cellular localization of telomerase and its recruitment to telomeres, and the regulation of telomerase activity. We also discuss the disease relevance of each of these steps of telomerase biogenesis.
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Affiliation(s)
- Caitlin M Roake
- Stanford Cancer Institute, Stanford University School of Medicine, Stanford, CA, USA.,Department of Medicine, Stanford University School of Medicine, Stanford, CA, USA.,Department of Biochemistry, Stanford University School of Medicine, Stanford, CA, USA
| | - Steven E Artandi
- Stanford Cancer Institute, Stanford University School of Medicine, Stanford, CA, USA. .,Department of Medicine, Stanford University School of Medicine, Stanford, CA, USA. .,Department of Biochemistry, Stanford University School of Medicine, Stanford, CA, USA.
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27
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Mahoney ER, Dumitrescu L, Seto M, Nudelman KNH, Buckley RF, Gifford KA, Saykin AJ, Jefferson AJ, Hohman TJ. Telomere length associations with cognition depend on Alzheimer's disease biomarkers. ALZHEIMERS & DEMENTIA-TRANSLATIONAL RESEARCH & CLINICAL INTERVENTIONS 2019; 5:883-890. [PMID: 31890852 PMCID: PMC6926345 DOI: 10.1016/j.trci.2019.11.003] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Introduction While telomere shortening, a marker of cellular aging, may impact the progression of age-related neurodegenerative diseases, its association with cognition is unclear, particularly in the context of Alzheimer's disease (AD) pathology. Methods Telomere, cognitive, and CSF data from 482 participants in the AD Neuroimaging Initiative (148 cognitively normal, 283 mild cognitive impairment, 51 AD) was leveraged to assess telomere length associations with cognition (measured by memory and executive function) and interactions with CSF amyloid-β, tau, and APOE -ε4. Secondary analyses assessed brain volume and thickness outcomes. Results Longer telomeres at baseline were associated with faster executive function decline. Amyloid-β and tau interacted with telomere length on cognition, with longer telomeres related to faster decline among biomarker-positive individuals. Discussion Telomere associations with cognition shift with AD progression, with longer telomeres related to worse outcomes as pathology increases, highlighting the need for further investigation of telomere length along the AD neuropathological cascade.
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Affiliation(s)
- Emily R Mahoney
- Vanderbilt Memory and Alzheimer's Center, Vanderbilt University Medical Center, Nashville, TN, USA.,Vanderbilt Genetics Institute, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Logan Dumitrescu
- Vanderbilt Memory and Alzheimer's Center, Vanderbilt University Medical Center, Nashville, TN, USA.,Vanderbilt Genetics Institute, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Mabel Seto
- Vanderbilt Memory and Alzheimer's Center, Vanderbilt University Medical Center, Nashville, TN, USA.,Vanderbilt Genetics Institute, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Kelly N H Nudelman
- Indiana Alzheimer Disease Center, Indiana University School of Medicine, Indianapolis, IN, USA.,Department of Medical and Molecular Genetics, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Rachel F Buckley
- Department of Neurology, Massachusetts General Hospital, Boston, MA, USA
| | - Katie A Gifford
- Vanderbilt Memory and Alzheimer's Center, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Andrew J Saykin
- Department of Radiology & Imaging Sciences, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Angela J Jefferson
- Vanderbilt Memory and Alzheimer's Center, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Timothy J Hohman
- Vanderbilt Memory and Alzheimer's Center, Vanderbilt University Medical Center, Nashville, TN, USA.,Vanderbilt Genetics Institute, Vanderbilt University Medical Center, Nashville, TN, USA
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28
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Predictive and prognostic significance of telomerase levels/telomere length in tissues and peripheral blood in head and neck squamous cell carcinoma. Sci Rep 2019; 9:17572. [PMID: 31772219 PMCID: PMC6879742 DOI: 10.1038/s41598-019-54028-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2019] [Accepted: 11/05/2019] [Indexed: 01/09/2023] Open
Abstract
A growing body of evidence indicates that the expression of TERT, the catalytic subunit of telomerase, is a biological marker of progression in several cancers. We investigated the predictive and prognostic role of TERT levels and telomere length in tissues and peripheral blood in patients with head and neck squamous cell carcinoma (HNSCC). High TERT levels in cancer tissues were independently associated with worse response to therapy (odds ratio [OR]:6.26), regional failure (hazard ratio [HR]:5.75), progression (HR:2.12), and death (HR:3.53). Longer telomeres in the mucosa surrounding the tumor (SM) were independently associated with a lower risk of mucosal failure (HR:0.39). While telomere length in peripheral blood mononuclear cells (PBMC) significantly decreased with age, no correlation was found between age and telomere length in SM. No associations were found between TERT levels in plasma and telomere length in PBMC and the prognostic variables. High levels of TERT transcripts in cancer cells represent a reliable prognostic marker for identifying HNSCC patients with risk of progression. The altered relationship of telomere length to age in SM compared with PBMC suggests that in a subset of cases the phenotypically normal SM constitutes an acquired telomere-shortened epithelial field prone to genetic instability.
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29
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Nyambura LW, Muñoz AA, le Coutre P, Walden P. HLA class I-restricted T cell epitopes isolated and identified from myeloid leukemia cells. Sci Rep 2019; 9:14029. [PMID: 31575892 PMCID: PMC6773711 DOI: 10.1038/s41598-019-50341-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2019] [Accepted: 09/11/2019] [Indexed: 12/19/2022] Open
Abstract
Leukemia-associated antigens (LAAs) and HLA-I epitopes published previously have shown promise in inducing leukemia-specific T cell responses. However, the clinical responses are limited, and clinical effectiveness is yet to be achieved. Limitations, among others, being the LAAs themselves, the indirect approach to HLA-I epitope identification by reverse immunology, and the use of single or few LAAs and HLA-I epitopes, which limits the spectrum of inducible tumor-specific T cells. Use of a direct approach to identify naturally processed and presented HLA-I epitopes from LAAs, and higher numbers of antigens for T cell-mediated immunotherapy for leukemia may enhance clinical responses and broaden clinical effectiveness. In a prior study we used immunoaffinity purification of HLA-I peptide complexes from the differentiated myeloid tumor cell lines MUTZ3 and THP1 coupled to high-performance liquid chromatography tandem mass spectrometry (LC-MS/MS). From this we identified in the current study seven new HLA-I epitopes and the corresponding LAAs for myeloid leukemia. In comparison, the myeloid HLA-I epitopes reported here were generally stronger HLA-binders that induce stronger T cell responses than those previously published, and their source LAAs had higher immunogenicity, higher expression levels in myeloid tumors cells compared to normal hemopoietin and other major normal tissues, and more protein interaction partners, and they are targeted by CD8 T cells in CML patients. This study analyses and compares the LAAs and HLA-I epitopes based on various immunotherapeutic targets selection criteria, and highlights new targets for T cell-mediated immunotherapy for leukemia.
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Affiliation(s)
- Lydon Wainaina Nyambura
- Department of Dermatology, Venerology and Allergology, Clinical Research Group 'Tumor Immunology', Charité - Universitätsmedizin Berlin corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, 10098, Berlin, Germany
| | - Alejandro Azorin Muñoz
- Department of Dermatology, Venerology and Allergology, Clinical Research Group 'Tumor Immunology', Charité - Universitätsmedizin Berlin corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, 10098, Berlin, Germany
| | - Philipp le Coutre
- Medical Department, Division of Hematology and Oncology, Charité - Universitätsmedizin Berlin corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, 10098, Berlin, Germany
| | - Peter Walden
- Department of Dermatology, Venerology and Allergology, Clinical Research Group 'Tumor Immunology', Charité - Universitätsmedizin Berlin corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, 10098, Berlin, Germany.
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30
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Telomere length measurement in tumor and non‐tumor cells as a valuable prognostic for tumor progression. Cancer Genet 2019; 238:50-61. [DOI: 10.1016/j.cancergen.2019.07.007] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2019] [Revised: 07/09/2019] [Accepted: 07/22/2019] [Indexed: 01/01/2023]
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31
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Patrick M, Weng NP. Expression and regulation of telomerase in human T cell differentiation, activation, aging and diseases. Cell Immunol 2019; 345:103989. [PMID: 31558266 DOI: 10.1016/j.cellimm.2019.103989] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2019] [Revised: 09/18/2019] [Accepted: 09/18/2019] [Indexed: 12/15/2022]
Abstract
Telomeres are essential for chromosomal integrity. Telomere shortening during cell division restricts cellular proliferative capacity and leads to cellular senescence when critically shortened telomere lengths are reached. Similar to hematopoietic stem cells, T cells can upregulate telomerase activity to compensate for telomere loss incurred during proliferation in response to engagement of the T cell antigen receptor (TCR) or exposure to homeostatic cytokines. However, this compensation for telomere loss by telomerase in T cells is imperfect or limited, as shortening of T cell telomeres is observed in human aging and during in vitro longterm culture. In this review, we summarize the current state of knowledge regarding the expression and regulation of telomerase in human T cells and changes of telomerase expression during development, activation, differentiation, aging and disease conditions. In conclusion, we discuss how controlled enhancement of telomerase activity could be a potential strategy to improve T cell function in the elderly and in immunotherapy.
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Affiliation(s)
- Michael Patrick
- Laboratory of Molecular Biology and Immunology, National Institute on Aging, National Institutes of Health, Baltimore, MD 21224, USA
| | - Nan-Ping Weng
- Laboratory of Molecular Biology and Immunology, National Institute on Aging, National Institutes of Health, Baltimore, MD 21224, USA.
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32
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Patrick MS, Cheng NL, Kim J, An J, Dong F, Yang Q, Zou I, Weng NP. Human T Cell Differentiation Negatively Regulates Telomerase Expression Resulting in Reduced Activation-Induced Proliferation and Survival. Front Immunol 2019; 10:1993. [PMID: 31497023 PMCID: PMC6712505 DOI: 10.3389/fimmu.2019.01993] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2019] [Accepted: 08/07/2019] [Indexed: 01/10/2023] Open
Abstract
Maintenance of telomeres is essential for preserving T cell proliferative responses yet the precise role of telomerase in human T cell differentiation, function, and aging is not fully understood. Here we analyzed human telomerase reverse transcriptase (hTERT) expression and telomerase activity in six T cell subsets from 111 human adults and found that levels of hTERT mRNA and telomerase activity had an ordered decrease from naïve (TN) to central memory (TCM) to effector memory (TEM) cells and were higher in CD4+ than their corresponding CD8+ subsets. This differentiation-related reduction of hTERT mRNA and telomerase activity was preserved after activation. Furthermore, the levels of hTERT mRNA and telomerase activity were positively correlated with the degree of activation-induced proliferation and survival of T cells in vitro. Partial knockdown of hTERT by an anti-sense oligo in naïve CD4+ cells led to a modest but significant reduction of cell proliferation. Finally, we found that activation-induced levels of telomerase activity in CD4+ TN and TCM cells were significantly lower in old than in young subjects. These findings reveal that hTERT/telomerase expression progressively declines during T cell differentiation and age-associated reduction of activation-induced expression of hTERT/telomerase mainly affects naïve CD4+ T cells and suggest that enhancing telomerase activity could be a strategy to improve T cell function in the elderly.
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Affiliation(s)
| | | | | | | | | | | | | | - Nan-ping Weng
- Laboratory of Molecular Biology and Immunology, National Institute on Aging, National Institutes of Health, Baltimore, MD, United States
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33
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Molecular and Cellular Bases of Immunosenescence, Inflammation, and Cardiovascular Complications Mimicking "Inflammaging" in Patients with Systemic Lupus Erythematosus. Int J Mol Sci 2019; 20:ijms20163878. [PMID: 31395799 PMCID: PMC6721773 DOI: 10.3390/ijms20163878] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2019] [Revised: 08/04/2019] [Accepted: 08/05/2019] [Indexed: 12/19/2022] Open
Abstract
Systemic lupus erythematosus (SLE) is an archetype of systemic autoimmune disease, characterized by the presence of diverse autoantibodies and chronic inflammation. There are multiple factors involved in lupus pathogenesis, including genetic/epigenetic predisposition, sexual hormone imbalance, environmental stimulants, mental/psychological stresses, and undefined events. Recently, many authors noted that "inflammaging", consisting of immunosenescence and inflammation, is a common feature in aging people and patients with SLE. It is conceivable that chronic oxidative stresses originating from mitochondrial dysfunction, defective bioenergetics, abnormal immunometabolism, and premature telomere erosion may accelerate immune cell senescence in patients with SLE. The mitochondrial dysfunctions in SLE have been extensively investigated in recent years. The molecular basis of normoglycemic metabolic syndrome has been found to be relevant to the production of advanced glycosylated and nitrosative end products. Besides, immunosenescence, autoimmunity, endothelial cell damage, and decreased tissue regeneration could be the results of premature telomere erosion in patients with SLE. Herein, the molecular and cellular bases of inflammaging and cardiovascular complications in SLE patients will be extensively reviewed from the aspects of mitochondrial dysfunctions, abnormal bioenergetics/immunometabolism, and telomere/telomerase disequilibrium.
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34
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da Silva JL, Dos Santos ALS, Nunes NCC, de Moraes Lino da Silva F, Ferreira CGM, de Melo AC. Cancer immunotherapy: the art of targeting the tumor immune microenvironment. Cancer Chemother Pharmacol 2019; 84:227-240. [PMID: 31240384 DOI: 10.1007/s00280-019-03894-3] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2018] [Accepted: 06/14/2019] [Indexed: 01/07/2023]
Abstract
For many decades, cancer treatment has been strongly directed toward the development of cytotoxic and cytostatic drugs, quite often leading to disappointing results due to the inter- and intra-tumoral heterogeneity. Lately, this intra-cellular look has given way to the understanding of the tumor microenvironment, thus enabling modification of the immunological dynamics between tumor cells and their host. An era of new drugs aiming to unlock the host immune system against tumor cells is steadily increasing. Strategies involving adoptive cell therapy, therapeutic vaccines, immune checkpoint inhibitors and so on have provided spectacular clinical responses and increased survival in previously refractory settings and "hard-to-treat" cancers. Based on a comprehensive search in the main scientific databases, annals of recent renowned oncology congresses and platforms of ongoing trials, the clinical pharmacology characteristics of the main classes of immunotherapeutic agents, as well as the new treatment strategies related to immunotherapy in solid tumors, are carefully discussed throughout this review.
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Affiliation(s)
- Jesse Lopes da Silva
- Clinic Oncomed, Brazilian National Cancer Institute (INCA), Rio de Janeiro, Brazil.
- Oncomed Clinic Oncologica, Niterói, Rio de Janeiro, 24220-300, Brazil.
| | | | - Natalia Cristina Cardoso Nunes
- Clinic Oncomed, Brazilian National Cancer Institute (INCA), Rio de Janeiro, Brazil
- Oncoclinicas Institute for Research and Education, Sao Paulo, Brazil
| | | | | | - Andreia Cristina de Melo
- Clinic Oncomed, Brazilian National Cancer Institute (INCA), Rio de Janeiro, Brazil
- Oncoclinicas Institute for Research and Education, Sao Paulo, Brazil
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35
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Abstract
Telomeres are specialised structures at the end of linear chromosomes. They consist of tandem repeats of the hexanucleotide sequence TTAGGG, as well as a protein complex called shelterin. Together, they form a protective loop structure against chromosome fusion and degradation. Shortening or damage to telomeres and opening of the loop induce an uncapped state that triggers a DNA damage response resulting in senescence or apoptosis.Average telomere length, usually measured in human blood lymphocytes, was thought to be a biomarker for ageing, survival and mortality. However, it becomes obvious that regulation of telomere length is very complex and involves multiple processes. For example, the "end replication problem" during DNA replication as well as oxidative stress are responsible for the shortening of telomeres. In contrast, telomerase activity can potentially counteract telomere shortening when it is able to access and interact with telomeres. However, while highly active during development and in cancer cells, the enzyme is down-regulated in most human somatic cells with a few exceptions such as human lymphocytes. In addition, telomeres can be transcribed, and the transcription products called TERRA are involved in telomere length regulation.Thus, telomere length and their integrity are regulated at many different levels, and we only start to understand this process under conditions of increased oxidative stress, inflammation and during diseases as well as the ageing process.This chapter aims to describe our current state of knowledge on telomeres and telomerase and their regulation in order to better understand their role for the ageing process.
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36
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Piekna-Przybylska D, Maggirwar SB. CD4+ memory T cells infected with latent HIV-1 are susceptible to drugs targeting telomeres. Cell Cycle 2018; 17:2187-2203. [PMID: 30198385 DOI: 10.1080/15384101.2018.1520568] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
The population of HIV reservoir in infected person is very small, but extremely long-lived and is a major obstacle for an HIV cure. We previously showed that cells with established HIV latency have deficiencies in DNA damage response (DDR). Here, we investigated ability of HIV-1 to interfere with telomere maintenance, and the effects of targeting telomeres on latently infected cells. Our results show that telomeres are elongated in cultured primary memory CD4 + T cells (TCM) after HIV-1 infection and when virus latency is established. Similarly, much longer telomeres were found in several Jurkat-derived latently infected cell lines, indicating that virus stimulates telomere elongation. Exposing primary CD4+ TCM cells to BRACO19, an agent targeting telomeres, resulted in a higher rate of apoptosis for infected cultures at day 3 post-infection, during HIV-1 latency and for PMA-stimulated cultures with low level of HIV-1 reactivation. Importantly, BRACO19 induced apoptosis in infected cells with potency similar to etoposide and camptothecin, whereas uninfected cells were less affected by BRACO19. We also determined that apoptosis induced by BRACO19 is not caused by telomeres shortening, but is related to formation of gamma-H2AX, implicating DNA damage or uncapping of telomeres, which triggers genome instability. In conclusion, our results indicate that HIV-1 stimulates telomere elongation during latency, suggesting that HIV reservoir has greater capacity for clonal expansion and extended lifespan. Higher rates of apoptosis in response to BRACO19 treatment suggest that HIV reservoirs are more susceptible to targeting telomere maintenance and to inhibitors targeting DDR, which is also involved in stabilizing telomeres.
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Affiliation(s)
- Dorota Piekna-Przybylska
- a Department of Microbiology and Immunology, School of Medicine and Dentistry , University of Rochester , Rochester , NY , USA
| | - Sanjay B Maggirwar
- a Department of Microbiology and Immunology, School of Medicine and Dentistry , University of Rochester , Rochester , NY , USA
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37
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Contact-independent suppressive activity of regulatory T cells is associated with telomerase inhibition, telomere shortening and target lymphocyte apoptosis. Mol Immunol 2018; 101:229-244. [PMID: 30025223 DOI: 10.1016/j.molimm.2018.07.017] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2018] [Revised: 07/02/2018] [Accepted: 07/11/2018] [Indexed: 02/08/2023]
Abstract
Regulatory T cells (Tregs) play a fundamental role in the maintenance of immunological tolerance by suppressing effector target T, B and NK lymphocytes. Contact-dependent suppression mechanisms have been well-studied, though contact-independent Treg activity is not fully understood. In the present study, we showed that human native Tregs, as well as induced ex vivo Tregs, can cause in vitro telomere-dependent senescence in target T, B and NK cells in a contact-independent manner. The co-cultivation of target cells with Tregs separated through porous membranes induced alternative splicing of the telomerase catalytic subunit hTERT (human Telomerase Reverse Transcriptase), which suppressed telomerase activity. Induction of the hTERT splicing variant was associated with increased expression of the apoptotic endonuclease EndoG, a splicing regulator. Inhibited telomerase in target cells co-cultivated with Tregs for a long period of time led to a decrease in their telomere lengths, cell cycle arrest, conversion of the target cells to replicative senescence and apoptotic death. Induced Tregs showed the ability to up-regulate EndoG expression, TERT alternative splicing and telomerase inhibition in mouse T, B and NK cells after in vivo administration. The results of the present study describe a novel mechanism of contact-independent Treg cell suppression that induces telomerase inhibition through the EndoG-provoked alternative splicing of hTERT and converts cells to senescence and apoptosis phenotypes.
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38
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Zhdanov DD, Gladilina YA, Pokrovsky VS, Grishin DV, Grachev VA, Orlova VS, Pokrovskaya MV, Alexandrova SS, Sokolov NN. Murine regulatory T cells induce death of effector T, B, and NK lymphocytes through a contact-independent mechanism involving telomerase suppression and telomere-associated senescence. Cell Immunol 2018; 331:146-160. [PMID: 29935763 DOI: 10.1016/j.cellimm.2018.06.008] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2018] [Revised: 05/22/2018] [Accepted: 06/18/2018] [Indexed: 12/30/2022]
Abstract
Regulatory T cells (Tregs) suppress the activity of effector T, B and NK lymphocytes and sustain immunological tolerance, but the proliferative activity of suppressed cells remains unexplored. In the present study, we report that mouse Tregs can induce replicative senescence and the death of responder mouse CD4+CD25- T cells, CD8+ T cells, B cells and NK cells in vitro and in vivo. Contact-independent in vitro co-cultivation with Tregs up-regulated endonuclease G (EndoG) expression and its translocation to the nucleus in responder cells. EndoG localization in the nucleus induced alternative mRNA splicing of the telomerase catalytic subunit Tert and telomerase inhibition. The lack of telomerase activity in proliferating cells led to telomere loss followed by the development of senescence and cell death. Injection of Tregs into mice resulted in EndoG-associated alternative splicing of Tert, telomerase inhibition, telomere loss, senescence development and increased cell death in vivo. The present study describes a novel contact-independent mechanism by which Tregs specify effector cell fate and provides new insights into cellular crosstalk related to immune suppression.
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Affiliation(s)
- Dmitry D Zhdanov
- Institute of Biomedical Chemistry, Pogodinskaya st 10/8, 119121 Moscow, Russia; Peoples Friendship University of Russia (RUDN University), Miklukho-Maklaya 6, 117198 Moscow, Russia.
| | - Yulia A Gladilina
- Institute of Biomedical Chemistry, Pogodinskaya st 10/8, 119121 Moscow, Russia
| | - Vadim S Pokrovsky
- Institute of Biomedical Chemistry, Pogodinskaya st 10/8, 119121 Moscow, Russia; Peoples Friendship University of Russia (RUDN University), Miklukho-Maklaya 6, 117198 Moscow, Russia; N.N. Blokhin Cancer Research Center, Kashirskoe Shosse 24, 115478 Moscow, Russia
| | - Dmitry V Grishin
- Institute of Biomedical Chemistry, Pogodinskaya st 10/8, 119121 Moscow, Russia
| | - Vladimir A Grachev
- Peoples Friendship University of Russia (RUDN University), Miklukho-Maklaya 6, 117198 Moscow, Russia
| | - Valentina S Orlova
- Peoples Friendship University of Russia (RUDN University), Miklukho-Maklaya 6, 117198 Moscow, Russia
| | | | | | - Nikolay N Sokolov
- Institute of Biomedical Chemistry, Pogodinskaya st 10/8, 119121 Moscow, Russia
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39
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D'Angelo SP, Melchiori L, Merchant MS, Bernstein D, Glod J, Kaplan R, Grupp S, Tap WD, Chagin K, Binder GK, Basu S, Lowther DE, Wang R, Bath N, Tipping A, Betts G, Ramachandran I, Navenot JM, Zhang H, Wells DK, Van Winkle E, Kari G, Trivedi T, Holdich T, Pandite L, Amado R, Mackall CL. Antitumor Activity Associated with Prolonged Persistence of Adoptively Transferred NY-ESO-1 c259T Cells in Synovial Sarcoma. Cancer Discov 2018; 8:944-957. [PMID: 29891538 DOI: 10.1158/2159-8290.cd-17-1417] [Citation(s) in RCA: 297] [Impact Index Per Article: 49.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2017] [Revised: 04/24/2018] [Accepted: 05/18/2018] [Indexed: 12/17/2022]
Abstract
We evaluated the safety and activity of autologous T cells expressing NY-ESO-1c259, an affinity-enhanced T-cell receptor (TCR) recognizing an HLA-A2-restricted NY-ESO-1/LAGE1a-derived peptide, in patients with metastatic synovial sarcoma (NY-ESO-1c259T cells). Confirmed antitumor responses occurred in 50% of patients (6/12) and were characterized by tumor shrinkage over several months. Circulating NY-ESO-1c259T cells were present postinfusion in all patients and persisted for at least 6 months in all responders. Most of the infused NY-ESO-1c259T cells exhibited an effector memory phenotype following ex vivo expansion, but the persisting pools comprised largely central memory and stem-cell memory subsets, which remained polyfunctional and showed no evidence of T-cell exhaustion despite persistent tumor burdens. Next-generation sequencing of endogenous TCRs in CD8+ NY-ESO-1c259T cells revealed clonal diversity without contraction over time. These data suggest that regenerative pools of NY-ESO-1c259T cells produced a continuing supply of effector cells to mediate sustained, clinically meaningful antitumor effects.Significance: Metastatic synovial sarcoma is incurable with standard therapy. We employed engineered T cells targeting NY-ESO-1, and the data suggest that robust, self-regenerating pools of CD8+ NY-ESO-1c259T cells produce a continuing supply of effector cells over several months that mediate clinically meaningful antitumor effects despite prolonged exposure to antigen. Cancer Discov; 8(8); 944-57. ©2018 AACR.See related commentary by Keung and Tawbi, p. 914This article is highlighted in the In This Issue feature, p. 899.
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Affiliation(s)
- Sandra P D'Angelo
- Memorial Sloan Kettering Cancer Center and Weill Cornell Medical College, New York, New York. E-mail:
| | - Luca Melchiori
- Adaptimmune, Oxford, United Kingdom, and Philadelphia, Pennsylvania
| | | | | | - John Glod
- Pediatric Oncology Branch, NCI, Bethesda, Maryland
| | | | - Stephan Grupp
- Children's Hospital of Philadelphia, Philadelphia, Pennsylvania
| | - William D Tap
- Memorial Sloan Kettering Cancer Center and Weill Cornell Medical College, New York, New York
| | - Karen Chagin
- Adaptimmune, Oxford, United Kingdom, and Philadelphia, Pennsylvania
| | | | - Samik Basu
- Adaptimmune, Oxford, United Kingdom, and Philadelphia, Pennsylvania
| | - Daniel E Lowther
- Adaptimmune, Oxford, United Kingdom, and Philadelphia, Pennsylvania
| | - Ruoxi Wang
- Adaptimmune, Oxford, United Kingdom, and Philadelphia, Pennsylvania
| | - Natalie Bath
- Adaptimmune, Oxford, United Kingdom, and Philadelphia, Pennsylvania
| | - Alex Tipping
- Adaptimmune, Oxford, United Kingdom, and Philadelphia, Pennsylvania
| | - Gareth Betts
- Adaptimmune, Oxford, United Kingdom, and Philadelphia, Pennsylvania
| | | | | | - Hua Zhang
- Pediatric Oncology Branch, NCI, Bethesda, Maryland
| | - Daniel K Wells
- Parker Institute for Cancer Immunotherapy, San Francisco, California
| | - Erin Van Winkle
- Adaptimmune, Oxford, United Kingdom, and Philadelphia, Pennsylvania
| | - Gabor Kari
- Adaptimmune, Oxford, United Kingdom, and Philadelphia, Pennsylvania
| | - Trupti Trivedi
- Adaptimmune, Oxford, United Kingdom, and Philadelphia, Pennsylvania
| | - Tom Holdich
- Adaptimmune, Oxford, United Kingdom, and Philadelphia, Pennsylvania
| | - Lini Pandite
- Adaptimmune, Oxford, United Kingdom, and Philadelphia, Pennsylvania
| | - Rafael Amado
- Adaptimmune, Oxford, United Kingdom, and Philadelphia, Pennsylvania
| | - Crystal L Mackall
- Pediatric Oncology Branch, NCI, Bethesda, Maryland.,Parker Institute for Cancer Immunotherapy, San Francisco, California.,Stanford University, Stanford, California
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Richardson GD, Sage A, Bennaceur K, Al Zhrany N, Coelho-Lima J, Dookun E, Draganova L, Saretzki G, Breault DT, Mallat Z, Spyridopoulos I. Telomerase Mediates Lymphocyte Proliferation but Not the Atherosclerosis-Suppressive Potential of Regulatory T-Cells. Arterioscler Thromb Vasc Biol 2018; 38:1283-1296. [PMID: 29599138 PMCID: PMC5965929 DOI: 10.1161/atvbaha.117.309940] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2017] [Accepted: 03/05/2018] [Indexed: 01/05/2023]
Abstract
Supplemental Digital Content is available in the text. Objective— Atherosclerosis is an age-related disease characterized by systemic oxidative stress and low-grade inflammation. The role of telomerase and telomere length in atherogenesis remains contentious. Short telomeres of peripheral leukocytes are predictive for coronary artery disease. Conversely, attenuated telomerase has been demonstrated to be protective for atherosclerosis. Hence, a potential causative role of telomerase in atherogenesis is critically debated. Approach and Results— In this study, we used multiple mouse models to investigate the regulation of telomerase under oxidative stress as well as its impact on atherogenesis in vitro and in vivo. Using primary lymphocytes and myeloid cell cultures, we demonstrate that cultivation under hyperoxic conditions induced oxidative stress resulting in chronic activation of CD4+ cells and significantly reduced CD4+ T-cell proliferation. The latter was telomerase dependent because oxidative stress had no effect on the proliferation of primary lymphocytes isolated from telomerase knockout mice. In contrast, myeloid cell proliferation was unaffected by oxidative stress nor reliant on telomerase. Telomerase reverse transcriptase deficiency had no effect on regulatory T-cell (Treg) numbers in vivo or suppressive function ex vivo. Adoptive transfer of telomerase reverse transcriptase–/– Tregs into Rag2–/– ApoE–/– (recombination activating gene 2/apolipoprotein E) double knockout mice demonstrated that telomerase function was not required for the ability of Tregs to protect against atherosclerosis. However, telomere length was critical for Treg function. Conclusions— Telomerase contributes to lymphocyte proliferation but plays no major role in Treg function, provided that telomere length is not critically short. We suggest that oxidative stress may contribute to atherosclerosis via suppression of telomerase and acceleration of telomere attrition in Tregs.
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Affiliation(s)
- Gavin David Richardson
- From the Cardiovascular Research Centre, Institute of Genetic Medicine, International Centre for Life (G.D.R., K.B., N.A.Z., J.C.-L., E.D., L.D., I.S.)
| | - Andrew Sage
- Division of Cardiovascular Medicine, Department of Medicine, University of Cambridge, United Kingdom (A.S., Z.M.)
| | - Karim Bennaceur
- From the Cardiovascular Research Centre, Institute of Genetic Medicine, International Centre for Life (G.D.R., K.B., N.A.Z., J.C.-L., E.D., L.D., I.S.)
| | - Nayef Al Zhrany
- From the Cardiovascular Research Centre, Institute of Genetic Medicine, International Centre for Life (G.D.R., K.B., N.A.Z., J.C.-L., E.D., L.D., I.S.)
| | - Jose Coelho-Lima
- From the Cardiovascular Research Centre, Institute of Genetic Medicine, International Centre for Life (G.D.R., K.B., N.A.Z., J.C.-L., E.D., L.D., I.S.)
| | - Emily Dookun
- From the Cardiovascular Research Centre, Institute of Genetic Medicine, International Centre for Life (G.D.R., K.B., N.A.Z., J.C.-L., E.D., L.D., I.S.)
| | - Lilia Draganova
- From the Cardiovascular Research Centre, Institute of Genetic Medicine, International Centre for Life (G.D.R., K.B., N.A.Z., J.C.-L., E.D., L.D., I.S.)
| | - Gabriele Saretzki
- Institute for Cell and Molecular Biosciences, The Ageing Biology Centre, Newcastle University Institute for Ageing, Campus for Ageing and Vitality (G.S.), Newcastle University, Newcastle upon Tyne, United Kingdom
| | - David T Breault
- Division of Endocrinology, Boston Children's Hospital, Harvard Medical School, MA (D.T.B.).,Harvard Stem Cell Institute, Cambridge, MA (D.T.B.)
| | - Ziad Mallat
- Division of Cardiovascular Medicine, Department of Medicine, University of Cambridge, United Kingdom (A.S., Z.M.).,INSERM U970, Paris Cardiovascular Research Center, France (Z.M.).,Université Paris Descartes, Sorbonne Paris Cité, France (Z.M.)
| | - Ioakim Spyridopoulos
- From the Cardiovascular Research Centre, Institute of Genetic Medicine, International Centre for Life (G.D.R., K.B., N.A.Z., J.C.-L., E.D., L.D., I.S.)
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Zaki-Dizaji M, Akrami SM, Abolhassani H, Rezaei N, Aghamohammadi A. Ataxia telangiectasia syndrome: moonlighting ATM. Expert Rev Clin Immunol 2017; 13:1155-1172. [PMID: 29034753 DOI: 10.1080/1744666x.2017.1392856] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
INTRODUCTION Ataxia-telangiectasia (A-T) a multisystem disorder primarily characterized by cerebellar degeneration, telangiectasia, immunodeficiency, cancer susceptibility and radiation sensitivity. Identification of the gene defective in this syndrome, ataxia-telangiectasia mutated gene (ATM), and further characterization of the disorder together with a greater insight into the function of the ATM protein have expanded our knowledge about the molecular pathogenesis of this disease. Area covered: In this review, we have attempted to summarize the different roles of ATM signaling that have provided new insights into the diverse clinical phenotypes exhibited by A-T patients. Expert commentary: ATM, in addition to DNA repair response, is involved in many cytoplasmic roles that explain diverse phenotypes of A-T patients. It seems accumulation of DNA damage, persistent DNA damage response signaling, and chronic oxidative stress are the main players in the pathogenesis of this disease.
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Affiliation(s)
- Majid Zaki-Dizaji
- a Department of Medical Genetics, School of Medicine , Tehran University of Medical Sciences , Tehran , Iran.,b Research Center for Immunodeficiencies, Children's Medical Center , Tehran University of Medical Science , Tehran , Iran
| | - Seyed Mohammad Akrami
- a Department of Medical Genetics, School of Medicine , Tehran University of Medical Sciences , Tehran , Iran
| | - Hassan Abolhassani
- b Research Center for Immunodeficiencies, Children's Medical Center , Tehran University of Medical Science , Tehran , Iran.,c Division of Clinical Immunology, Department of Laboratory Medicine , Karolinska Institute at Karolinska University Hospital Huddinge , Stockholm , Sweden.,d Primary Immunodeficiency Diseases Network (PIDNet ), Universal Scientific Education and Research Network (USERN) , Stockholm , Sweden
| | - Nima Rezaei
- b Research Center for Immunodeficiencies, Children's Medical Center , Tehran University of Medical Science , Tehran , Iran.,e Department of Immunology and Biology, School of Medicine , Tehran University of Medical Sciences , Tehran , Iran.,f Network of Immunity in Infection, Malignancy and Autoimmunity (NIIMA) , Universal Scientific Education and Research Network (USERN) , Tehran , Iran
| | - Asghar Aghamohammadi
- b Research Center for Immunodeficiencies, Children's Medical Center , Tehran University of Medical Science , Tehran , Iran
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Abstract
BACKGROUND Telomeres are protein DNA structures present at the ends of chromosomes and are essential for genetic stability and cell replication. Telomerase is the enzyme complex that maintains telomere integrity. Hematopoietic stem cells express telomerase and contain long telomeres, which become shorter as cells differentiate and mature. The extent of telomere shortening and the level of telomerase activity often correlate with the presence and severity of some hematopoietic diseases. METHODS The fundamentals of telomeres and telomerase are reviewed, and the telomere biology of human hematopoietic cells is discussed. RESULTS Telomere length and telomerase activity are important in the self-renewal of hematopoietic stem cells. Changes within these compartments affect both normal hematopoietic cells and the generation of hematopoietic disease. Telomere length provides information pertaining to the proliferative history and potential of a hematopoietic cell. CONCLUSIONS The role of telomerase and telomeres within the hematopoietic compartment needs further clarification. Advances in our knowledge in this field may improve clinical outcomes for the treatment of hematologic disease.
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Affiliation(s)
- Ngaire Elwood
- Leukaemia Research Fund Stem Cell Laboratory, Department of Clinical Haematology and Oncology, Murdoch Children's Research Institute, Melbourne, Australia.
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The Maintenance of Telomere Length in CD28+ T Cells During T Lymphocyte Stimulation. Sci Rep 2017; 7:6785. [PMID: 28754961 PMCID: PMC5533788 DOI: 10.1038/s41598-017-05174-7] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2017] [Accepted: 05/24/2017] [Indexed: 12/21/2022] Open
Abstract
Telomerase activity is not readily detected in resting human T lymphocytes, however upon antigen presentation, telomerase is transiently upregulated. Presently, it is not known if telomerase activation is necessary for the proliferation of T cells or for the maintenance of telomere lengths. In this study, we found that telomerase activation is not required for the short- term proliferation of T cells and that telomeres progressively shorten in a heterogeneous population of T cells, even if telomerase is detected. By measuring telomerase activity at the single-cell level using quantitative ddPCR techniques (ddTRAP) and by monitoring changes in the shortest telomeres with more sensitive telomere length measurement assays, we show that only a subset of CD28+ T-cells have robust telomerase activity upon stimulation and are capable of maintaining their telomere lengths during induced proliferation. The study of this T-cell subset may lead to a better understanding on how telomerase is regulated and functions in immune cells.
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Stabilization of Telomere G-Quadruplexes Interferes with Human Herpesvirus 6A Chromosomal Integration. J Virol 2017; 91:JVI.00402-17. [PMID: 28468887 DOI: 10.1128/jvi.00402-17] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2017] [Accepted: 04/29/2017] [Indexed: 11/20/2022] Open
Abstract
Human herpesviruses 6A and 6B (HHV-6A/B) can integrate their genomes into the telomeres of human chromosomes using a mechanism that remains poorly understood. To achieve a better understanding of the HHV-6A/B integration mechanism, we made use of BRACO-19, a compound that stabilizes G-quadruplex secondary structures and prevents telomere elongation by the telomerase complex. First, we analyzed the folding of telomeric sequences into G-quadruplex structures and their binding to BRACO-19 using G-quadruplex-specific antibodies and surface plasmon resonance. Circular dichroism studies indicate that BRACO-19 modifies the conformation and greatly stabilizes the G-quadruplexes formed in G-rich telomeric DNA. Subsequently we assessed the effects of BRACO-19 on the HHV-6A initial phase of infection. Our results indicate that BRACO-19 does not affect entry of HHV-6A DNA into cells. We next investigated if stabilization of G-quadruplexes by BRACO-19 affected HHV-6A's ability to integrate its genome into host chromosomes. Incubation of telomerase-expressing cells with BRACO-19, such as HeLa and MCF-7, caused a significant reduction in the HHV-6A integration frequency (P < 0.002); in contrast, BRACO-19 had no effect on HHV-6 integration frequency in U2OS cells that lack telomerase activity and elongate their telomeres through alternative lengthening mechanisms. Our data suggest that the fluidity of telomeres is important for efficient chromosomal integration of HHV-6A and that interference with telomerase activity negatively affects the generation of cellular clones containing integrated HHV-6A.IMPORTANCE HHV-6A/B can integrate their genomes into the telomeres of infected cells. Telomeres consist of repeated hexanucleotides (TTAGGG) of various lengths (up to several kilobases) and end with a single-stranded 3' extension. To avoid recognition and induce a DNA damage response, the single-stranded overhang folds back on itself and forms a telomeric loop (T-loop) or adopts a tertiary structure, referred to as a G-quadruplex. In the current study, we have examined the effects of a G-quadruplex binding and stabilizing agent, BRACO-19, on HHV-6A chromosomal integration. By stabilizing G-quadruplex structures, BRACO-19 affects the ability of the telomerase complex to elongate telomeres. Our results indicate that BRACO-19 reduces the number of clones harboring integrated HHV-6A. This study is the first of its kind and suggests that telomerase activity is essential to restore a functional telomere of adequate length following HHV-6A integration.
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Guruprasad KP, Dash S, Shivakumar MB, Shetty PR, Raghu KS, Shamprasad BR, Udupi V, Acharya RV, Vidya PB, Nayak J, Mana AE, Moni R, Sankaran MT, Satyamoorthy K. Influence of Amalaki Rasayana on telomerase activity and telomere length in human blood mononuclear cells. J Ayurveda Integr Med 2017; 8:105-112. [PMID: 28602428 PMCID: PMC5497001 DOI: 10.1016/j.jaim.2017.01.007] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2016] [Revised: 01/13/2017] [Accepted: 01/13/2017] [Indexed: 12/20/2022] Open
Abstract
Background Indian traditional medicine practices use defined rasayana preparations to improve the quality of life in aged individuals. Amalaki Rasayana is one such rasayana prepared from the fruits of Phyllanthus emblica and is popularly used to prevent or treat various age related health conditions. Telomerase activity in the cells maintains telomere length and is implicated in ageing and various diseases wherein the shortening of telomere during ageing is controlled chiefly by the telomerase activity. Objective In the present study, we investigated telomerase activity and telomere length in the peripheral blood mononuclear cells of aged individuals administered with Amalaki Rasayana. Materials and methods Amalaki Rasayana was administered to healthy, aged (45–60 years) volunteers for 45 days after koshta shuddhi procedure. The telomerase activity and telomere length were analyzed on 0, 45th and 90th days of Amalaki Rasayana administration in peripheral blood mononuclear cells from these individuals and compared with age-matched placebo group and young volunteers (22–30 years). The data were compared between the groups. Results The results indicated an increase in telomerase activity with no discernible change in telomere length in the Amalaki administered participants. The comparison between young and aged participants revealed higher telomerase activity in young participants with no significant differences in telomere length. Conclusion The data indicate that the maintenance of telomere length is facilitated by an increase in telomerase activity upon rasayana administration in aged individuals and Amalaki Rasayana may prevent the erosion of telomeres over a period of time in aged individuals to promote healthy ageing.
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Affiliation(s)
- Kanive P Guruprasad
- School of Life Sciences, Manipal University, Planetarium Complex, Manipal, 576 104, Karnataka, India
| | - Sweta Dash
- School of Life Sciences, Manipal University, Planetarium Complex, Manipal, 576 104, Karnataka, India
| | - Marigowda B Shivakumar
- School of Life Sciences, Manipal University, Planetarium Complex, Manipal, 576 104, Karnataka, India
| | - Pavithra R Shetty
- School of Life Sciences, Manipal University, Planetarium Complex, Manipal, 576 104, Karnataka, India
| | - Kothanahalli S Raghu
- School of Life Sciences, Manipal University, Planetarium Complex, Manipal, 576 104, Karnataka, India
| | - Bhanuvalli R Shamprasad
- School of Life Sciences, Manipal University, Planetarium Complex, Manipal, 576 104, Karnataka, India
| | - Vishwanatha Udupi
- School of Life Sciences, Manipal University, Planetarium Complex, Manipal, 576 104, Karnataka, India
| | - Raviraj V Acharya
- Department of Medicine, Kasturba Medical College Hospital, Manipal University, Manipal, 576 104, Karnataka, India
| | - Prasanna B Vidya
- Sri Dharmasthala Manjunatheshwara College of Ayurveda, Kuthpady, Udyavara, Udupi, 574 118, Karnataka, India
| | - Jayakrishna Nayak
- Sri Dharmasthala Manjunatheshwara College of Ayurveda, Kuthpady, Udyavara, Udupi, 574 118, Karnataka, India
| | - Anandan E Mana
- Ayurvedic Hospital and Research Centre, Arya Vaidya Sala, Kottakkal, 676 503, Mallapuram District, Kerala, India
| | - Rajesh Moni
- Ayurvedic Hospital and Research Centre, Arya Vaidya Sala, Kottakkal, 676 503, Mallapuram District, Kerala, India
| | - Muraleedharan T Sankaran
- Ayurvedic Hospital and Research Centre, Arya Vaidya Sala, Kottakkal, 676 503, Mallapuram District, Kerala, India
| | - Kapaettu Satyamoorthy
- School of Life Sciences, Manipal University, Planetarium Complex, Manipal, 576 104, Karnataka, India.
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Herz C, Tran HTT, Landerer S, Gaus J, Schlotz N, Lehr L, Schäfer WR, Treeck O, Odongo GA, Skatchkov I, Lamy E. Normal human immune cells are sensitive to telomerase inhibition by Brassica-derived 3,3-diindolylmethane,partly mediated via ERα/β-AP1 signaling. Mol Nutr Food Res 2017; 61. [PMID: 28267258 DOI: 10.1002/mnfr.201600524] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2016] [Revised: 02/13/2017] [Accepted: 02/22/2017] [Indexed: 11/07/2022]
Abstract
SCOPE Indole-3-carbinol (I3C) and 3,3'-diindolylmethane (DIM) from Brassica plants are regarded as promising anticancer phytochemicals. The enzyme telomerase is a very attractive target for cancer therapeutics; in normal cells such as lymphocytes, it plays a decisive role for cell maintenance. The effect of I3C and DIM on telomerase in normal human immune cells (PBMC) was studied compared to leukaemia cells (HL-60). Signalling of telomerase regulation via estrogen receptor (ER) was addressed. METHODS AND RESULTS Short-term treatment with I3C and DIM inhibited telomerase activity in leukaemia cells (>30 μM I3C; >3 μM DIM). In CD3/CD28 activated PBMC, inhibition was stronger, though (>3 μM I3C; >1 μM DIM). DIM long-term treatment resulted in DNA damage induction and proliferation inhibition in PBMC as determined by the comet assay and CFSE staining, respectively. A relevance of ERα/β-AP1 signaling for telomerase inhibition on enzyme activity, but not transcription level became evident indicating a nonclassical mode for ER regulation of telomerase by DIM. CONCLUSION Although desired in cancer cells, this study identified a potential adverse impact of I3C and DIM on telomerase action in normal human immune cells, partly mediated by an ER-dependent mechanism. These new findings should be considered for potential chronic high-dose chemoprevention strategies using these compounds.
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Affiliation(s)
- Corinna Herz
- Molecular Preventive Medicine, Institute of Prevention and Cancer Epidemiology, University Medical Center Freiburg, Freiburg, Germany
| | - Hoai Thi Thu Tran
- Molecular Preventive Medicine, Institute of Prevention and Cancer Epidemiology, University Medical Center Freiburg, Freiburg, Germany
| | - Steffen Landerer
- Institute of Environmental Health Sciences, University Medical Center Freiburg, Freiburg, Germany
| | - Johanna Gaus
- Molecular Preventive Medicine, Institute of Prevention and Cancer Epidemiology, University Medical Center Freiburg, Freiburg, Germany
| | - Nina Schlotz
- Molecular Preventive Medicine, Institute of Prevention and Cancer Epidemiology, University Medical Center Freiburg, Freiburg, Germany
| | - Lia Lehr
- Molecular Preventive Medicine, Institute of Prevention and Cancer Epidemiology, University Medical Center Freiburg, Freiburg, Germany
| | - Wolfgang R Schäfer
- Department of Obstetrics & Gynecology, University Medical Center Freiburg, Freiburg, Germany
| | - Oliver Treeck
- Department of Gynecology and Obstetrics, University Medical Center Regensburg, Regensburg, Germany
| | - Grace Akinyi Odongo
- Molecular Preventive Medicine, Institute of Prevention and Cancer Epidemiology, University Medical Center Freiburg, Freiburg, Germany
| | - Ivan Skatchkov
- Molecular Preventive Medicine, Institute of Prevention and Cancer Epidemiology, University Medical Center Freiburg, Freiburg, Germany
| | - Evelyn Lamy
- Molecular Preventive Medicine, Institute of Prevention and Cancer Epidemiology, University Medical Center Freiburg, Freiburg, Germany
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Aubert G, Strauss KA, Lansdorp PM, Rider NL. Defects in lymphocyte telomere homeostasis contribute to cellular immune phenotype in patients with cartilage-hair hypoplasia. J Allergy Clin Immunol 2017; 140:1120-1129.e1. [PMID: 28126377 DOI: 10.1016/j.jaci.2016.11.051] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2015] [Revised: 10/18/2016] [Accepted: 11/01/2016] [Indexed: 12/20/2022]
Abstract
BACKGROUND Mutations in the long noncoding RNA RNase component of the mitochondrial RNA processing endoribonuclease (RMRP) give rise to the autosomal recessive condition cartilage-hair hypoplasia (CHH). The CHH disease phenotype has some overlap with dyskeratosis congenita, a well-known "telomere disorder." RMRP binds the telomerase reverse transcriptase (catalytic subunit) in some cell lines, raising the possibility that RMRP might play a role in telomere biology. OBJECTIVE We sought to determine whether a telomere phenotype is present in immune cells from patients with CHH and explore mechanisms underlying these observations. METHODS We assessed proliferative capacity and telomere length using flow-fluorescence in situ hybridization (in situ hybridization and flow cytometry) of primary lymphocytes from patients with CHH, carrier relatives, and control subjects. The role of telomerase holoenzyme components in gene expression and activity were assessed by using quantitative PCR and the telomere repeat amplification protocol from PBMCs and enriched lymphocyte cultures. RESULTS Lymphocyte cultures from patients with CHH display growth defects in vitro, which is consistent with an immune deficiency cellular phenotype. Here we show that telomere length and telomerase activity are impaired in primary lymphocyte subsets from patients with CHH. Notably, telomerase activity is affected in a gene dose-dependent manner when comparing heterozygote RMRP carriers with patients with CHH. Telomerase deficiency in patients with CHH is not mediated by abnormal telomerase gene transcript levels relative to those of endogenous genes. CONCLUSION These findings suggest that telomere deficiency is implicated in the CHH disease phenotype through an as yet unidentified mechanism.
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Affiliation(s)
- Geraldine Aubert
- Terry Fox Laboratory, BC Cancer Agency, Vancouver, British Columbia, Canada
| | | | - Peter M Lansdorp
- Terry Fox Laboratory, BC Cancer Agency, Vancouver, British Columbia, Canada; Division of Hematology, Department of Medicine, University of British Columbia, Vancouver, British Columbia, Canada; European Research Institute on the Biology of Aging, University of Groningen, University Medical Centre Groningen, Groningen, The Netherlands.
| | - Nicholas L Rider
- Section of Immunology, Allergy and Rheumatology, Texas Children's Hospital, Baylor College of Medicine, Houston, Tex.
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Telomerase: The Devil Inside. Genes (Basel) 2016; 7:genes7080043. [PMID: 27483324 PMCID: PMC4999831 DOI: 10.3390/genes7080043] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2016] [Revised: 07/23/2016] [Accepted: 07/25/2016] [Indexed: 01/04/2023] Open
Abstract
High telomerase activity is detected in nearly all human cancers but most human cells are devoid of telomerase activity. There is well-documented evidence that reactivation of telomerase occurs during cellular transformation. In humans, tumors can rely in reactivation of telomerase or originate in a telomerase positive stem/progenitor cell, or rely in alternative lengthening of telomeres, a telomerase-independent telomere-length maintenance mechanism. In this review, we will focus on the telomerase positive tumors. In this context, the recent findings that telomerase reverse transcriptase (TERT) promoter mutations represent the most common non-coding mutations in human cancer have flared up the long-standing discussion whether cancer originates from telomerase positive stem cells or telomerase reactivation is a final step in cellular transformation. Here, we will discuss the pros and cons of both concepts in the context of telomere length-dependent and telomere length-independent functions of telomerase. Together, these observations may provoke a re-evaluation of telomere and telomerase based therapies, both in telomerase inhibition for cancer therapy and telomerase activation for tissue regeneration and anti-ageing strategies.
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Ali A, Ullah F, Ali IS, Faraz A, Khan M, Shah STA, Ali N, Saeed M. Aberrant Promoter Methylation at CpG Cytosines Induce the Upregulation of the E2F5 Gene in Breast Cancer. J Breast Cancer 2016; 19:133-41. [PMID: 27382388 PMCID: PMC4929253 DOI: 10.4048/jbc.2016.19.2.133] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2016] [Accepted: 04/27/2016] [Indexed: 02/06/2023] Open
Abstract
Purpose The promoter methylation status of cell cycle regulatory genes plays a crucial role in the regulation of the eukaryotic cell cycle. CpG cytosines are actively subjected to methylation during tumorigenesis, resulting in gain/loss of function. E2F5 gene has growth repressive activities; various studies suggest its involvement in tumorigenesis. This study aims to investigate the epigenetic regulation of E2F5 in breast cancer to better understand tumor biology. Methods The promoter methylation status of 50 breast tumor tissues and adjacent normal control tissues was analyzed. mRNA expression was determined using SYBR® green quantitative polymerase chain reaction (PCR), and methylation-specific PCR was performed for bisulfite-modified genomic DNA using E2F5-specific primers to assess promoter methylation. Data was statistically analyzed. Results Significant (p<0.001) upregulation was observed in E2F5 expression among tumor tissues, relative to the control group. These samples were hypo-methylated at the E2F5 promoter region in the tumor tissues, compared to the control. Change in the methylation status (Δmeth) was significantly lower (p=0.022) in the tumor samples, indicating possible involvement in tumorigenesis. Patients at the postmenopausal stage showed higher methylation (75%) than those at the premenopausal stage (23.1%). Interestingly, methylation levels gradually increased from the early to the advanced stages of the disease (p<0.001), which suggests a putative role of E2F5 methylation in disease progression that can significantly modulate tumor biology at more advanced stage and at postmenopausal age (Pearson's r=0.99 and 0.86, respectively). Among tissues with different histological status, methylation frequency was higher in invasive lobular carcinoma (80.0%), followed by invasive ductal carcinoma (46.7%) and ductal carcinoma in situ (20.0%). Conclusion Methylation is an important epigenetic factor that might be involved in the upregulation of E2F5 gene in tumor tissues, which can be used as a prognostic marker for breast cancer.
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Affiliation(s)
- Arshad Ali
- Cancer Genetics and Epigenetics Lab, Department of Biosciences, COMSATS Institute of Information Technology, Islamabad, Pakistan.; Department of Biotechnology & Genetic Engineering, Kohat University of Science & Technology, Kohat, Pakistan
| | - Farman Ullah
- Cancer Genetics and Epigenetics Lab, Department of Biosciences, COMSATS Institute of Information Technology, Islamabad, Pakistan.; Department of Biotechnology & Genetic Engineering, Kohat University of Science & Technology, Kohat, Pakistan
| | - Irum Sabir Ali
- Department of Surgical C Unit, Post Graduate Medical Institution, Lady Reading Hospital, Peshawar, Pakistan
| | - Ahmad Faraz
- Department of Surgical C Unit, Post Graduate Medical Institution, Lady Reading Hospital, Peshawar, Pakistan
| | - Mumtaz Khan
- Department of Surgical C Unit, Post Graduate Medical Institution, Lady Reading Hospital, Peshawar, Pakistan
| | | | - Nawab Ali
- Department of Biotechnology & Genetic Engineering, Kohat University of Science & Technology, Kohat, Pakistan
| | - Muhammad Saeed
- Cancer Genetics and Epigenetics Lab, Department of Biosciences, COMSATS Institute of Information Technology, Islamabad, Pakistan
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Sakurai F, Narii N, Tomita K, Togo S, Takahashi K, Machitani M, Tachibana M, Ouchi M, Katagiri N, Urata Y, Fujiwara T, Mizuguchi H. Efficient detection of human circulating tumor cells without significant production of false-positive cells by a novel conditionally replicating adenovirus. MOLECULAR THERAPY-METHODS & CLINICAL DEVELOPMENT 2016; 3:16001. [PMID: 26966699 PMCID: PMC4774621 DOI: 10.1038/mtm.2016.1] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/22/2015] [Revised: 11/20/2015] [Accepted: 11/25/2015] [Indexed: 12/20/2022]
Abstract
Circulating tumor cells (CTCs) are promising biomarkers in several cancers, and thus methods and apparatuses for their detection and quantification in the blood have been actively pursued. A novel CTC detection system using a green fluorescence protein (GFP)-expressing conditionally replicating adenovirus (Ad) (rAd-GFP) was recently developed; however, there is concern about the production of false-positive cells (GFP-positive normal blood cells) when using rAd-GFP, particularly at high titers. In addition, CTCs lacking or expressing low levels of coxsackievirus-adenovirus receptor (CAR) cannot be detected by rAd-GFP, because rAd-GFP is constructed based on Ad serotype 5, which recognizes CAR. In order to suppress the production of false-positive cells, sequences perfectly complementary to blood cell-specific microRNA, miR-142-3p, were incorporated into the 3'-untranslated region of the E1B and GFP genes. In addition, the fiber protein was replaced with that of Ad serotype 35, which recognizes human CD46, creating rAdF35-142T-GFP. rAdF35-142T-GFP efficiently labeled not only CAR-positive tumor cells but also CAR-negative tumor cells with GFP. The numbers of false-positive cells were dramatically lower for rAdF35-142T-GFP than for rAd-GFP. CTCs in the blood of cancer patients were detected by rAdF35-142T-GFP with a large reduction in false-positive cells.
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Affiliation(s)
- Fuminori Sakurai
- Laboratory of Biochemistry and Molecular Biology, Graduate School of Pharmaceutical Sciences, Osaka University, Osaka, Japan; Laboratory of Regulatory Sciences for Oligonucleotide Therapeutics, Clinical Drug Development Unit, Graduate School of Pharmaceutical Sciences, Osaka University, Osaka, Japan
| | - Nobuhiro Narii
- Laboratory of Biochemistry and Molecular Biology, Graduate School of Pharmaceutical Sciences, Osaka University , Osaka, Japan
| | - Kyoko Tomita
- Laboratory of Biochemistry and Molecular Biology, Graduate School of Pharmaceutical Sciences, Osaka University , Osaka, Japan
| | - Shinsaku Togo
- Division of Respiratory Medicine, Juntendo University Faculty of Medicine & Graduate School of Medicine , Tokyo, Japan
| | - Kazuhisa Takahashi
- Division of Respiratory Medicine, Juntendo University Faculty of Medicine & Graduate School of Medicine , Tokyo, Japan
| | - Mitsuhiro Machitani
- Laboratory of Biochemistry and Molecular Biology, Graduate School of Pharmaceutical Sciences, Osaka University , Osaka, Japan
| | - Masashi Tachibana
- Laboratory of Biochemistry and Molecular Biology, Graduate School of Pharmaceutical Sciences, Osaka University , Osaka, Japan
| | | | | | | | - Toshiyoshi Fujiwara
- Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences , Okayama, Japan
| | - Hiroyuki Mizuguchi
- Laboratory of Biochemistry and Molecular Biology, Graduate School of Pharmaceutical Sciences, Osaka University, Osaka, Japan; The Center for Advanced Medical Engineering and Informatics, Osaka University, Osaka, Japan; Laboratory of Hepatocyte Differentiation, National Institute of Biomedical Innovation, Osaka, Japan; iPS Cell-Based Research Project on Hepatic Toxicity and Metabolism, Graduate School of Pharmaceutical Sciences, Osaka University, Osaka, Japan
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