1
|
Wagner KD, Wagner N. The Senescence Markers p16INK4A, p14ARF/p19ARF, and p21 in Organ Development and Homeostasis. Cells 2022; 11:cells11121966. [PMID: 35741095 PMCID: PMC9221567 DOI: 10.3390/cells11121966] [Citation(s) in RCA: 33] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2022] [Revised: 06/15/2022] [Accepted: 06/15/2022] [Indexed: 02/07/2023] Open
Abstract
It is widely accepted that senescent cells accumulate with aging. They are characterized by replicative arrest and the release of a myriad of factors commonly called the senescence-associated secretory phenotype. Despite the replicative cell cycle arrest, these cells are metabolically active and functional. The release of SASP factors is mostly thought to cause tissue dysfunction and to induce senescence in surrounding cells. As major markers for aging and senescence, p16INK4, p14ARF/p19ARF, and p21 are established. Importantly, senescence is also implicated in development, cancer, and tissue homeostasis. While many markers of senescence have been identified, none are able to unambiguously identify all senescent cells. However, increased levels of the cyclin-dependent kinase inhibitors p16INK4A and p21 are often used to identify cells with senescence-associated phenotypes. We review here the knowledge of senescence, p16INK4A, p14ARF/p19ARF, and p21 in embryonic and postnatal development and potential functions in pathophysiology and homeostasis. The establishment of senolytic therapies with the ultimate goal to improve healthy aging requires care and detailed knowledge about the involvement of senescence and senescence-associated proteins in developmental processes and homeostatic mechanism. The review contributes to these topics, summarizes open questions, and provides some directions for future research.
Collapse
|
2
|
Hong X, Wang L, Zhang K, Liu J, Liu JP. Molecular Mechanisms of Alveolar Epithelial Stem Cell Senescence and Senescence-Associated Differentiation Disorders in Pulmonary Fibrosis. Cells 2022; 11:cells11050877. [PMID: 35269498 PMCID: PMC8909789 DOI: 10.3390/cells11050877] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2022] [Revised: 03/01/2022] [Accepted: 03/02/2022] [Indexed: 02/04/2023] Open
Abstract
Pulmonary senescence is accelerated by unresolved DNA damage response, underpinning susceptibility to pulmonary fibrosis. Recently it was reported that the SARS-Cov-2 viral infection induces acute pulmonary epithelial senescence followed by fibrosis, although the mechanism remains unclear. Here, we examine roles of alveolar epithelial stem cell senescence and senescence-associated differentiation disorders in pulmonary fibrosis, exploring the mechanisms mediating and preventing pulmonary fibrogenic crisis. Notably, the TGF-β signalling pathway mediates alveolar epithelial stem cell senescence by mechanisms involving suppression of the telomerase reverse transcriptase gene in pulmonary fibrosis. Alternatively, telomere uncapping caused by stress-induced telomeric shelterin protein TPP1 degradation mediates DNA damage response, pulmonary senescence and fibrosis. However, targeted intervention of cellular senescence disrupts pulmonary remodelling and fibrosis by clearing senescent cells using senolytics or preventing senescence using telomere dysfunction inhibitor (TELODIN). Studies indicate that the development of senescence-associated differentiation disorders is reprogrammable and reversible by inhibiting stem cell replicative senescence in pulmonary fibrosis, providing a framework for targeted intervention of the molecular mechanisms of alveolar stem cell senescence and pulmonary fibrosis. Abbreviations: DPS, developmental programmed senescence; IPF, idiopathic pulmonary fibrosis; OIS, oncogene-induced replicative senescence; SADD, senescence-associated differentiation disorder; SALI, senescence-associated low-grade inflammation; SIPS, stress-induced premature senescence; TERC, telomerase RNA component; TERT, telomerase reverse transcriptase; TIFs, telomere dysfunction-induced foci; TIS, therapy-induced senescence; VIS, virus-induced senescence.
Collapse
Affiliation(s)
- Xiaojing Hong
- Institute of Ageing Research, Hangzhou Normal University School of Medicine, Hangzhou 311121, China; (X.H.); (L.W.); (K.Z.); (J.L.)
| | - Lihui Wang
- Institute of Ageing Research, Hangzhou Normal University School of Medicine, Hangzhou 311121, China; (X.H.); (L.W.); (K.Z.); (J.L.)
| | - Kexiong Zhang
- Institute of Ageing Research, Hangzhou Normal University School of Medicine, Hangzhou 311121, China; (X.H.); (L.W.); (K.Z.); (J.L.)
| | - Jun Liu
- Institute of Ageing Research, Hangzhou Normal University School of Medicine, Hangzhou 311121, China; (X.H.); (L.W.); (K.Z.); (J.L.)
| | - Jun-Ping Liu
- Institute of Ageing Research, Hangzhou Normal University School of Medicine, Hangzhou 311121, China; (X.H.); (L.W.); (K.Z.); (J.L.)
- Department of Immunology and Pathology, Monash University Faculty of Medicine, Prahran, VIC 3181, Australia
- Hudson Institute of Medical Research, Monash University Department of Molecular and Translational Science, Clayton, VIC 3168, Australia
- Correspondence:
| |
Collapse
|
3
|
Zhang K, Xu L, Cong YS. Telomere Dysfunction in Idiopathic Pulmonary Fibrosis. Front Med (Lausanne) 2021; 8:739810. [PMID: 34859008 PMCID: PMC8631932 DOI: 10.3389/fmed.2021.739810] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2021] [Accepted: 10/05/2021] [Indexed: 12/14/2022] Open
Abstract
Idiopathic pulmonary fibrosis is an age-dependent progressive and fatal lung disease of unknown etiology, which is characterized by the excessive accumulation of extracellular matrix inside the interstitial layer of the lung parenchyma that leads to abnormal scar architecture and compromised lung function capacity. Recent genetic studies have attributed the pathological genes or genetic mutations associated with familial idiopathic pulmonary fibrosis (IPF) and sporadic IPF to telomere-related components, suggesting that telomere dysfunction is an important determinant of this disease. In this study, we summarized recent advances in our understanding of how telomere dysfunction drives IPF genesis. We highlighted the key role of alveolar stem cell dysfunction caused by telomere shortening or telomere uncapping, which bridged the gap between telomere abnormalities and fibrotic lung pathology. We emphasized that senescence-associated secretory phenotypes, innate immune cell infiltration, and/or inflammation downstream of lung stem cell dysfunction influenced the native microenvironment and local cell signals, including increased transforming growth factor-beta (TGF-β) signaling in the lung, to induce pro-fibrotic conditions. In addition, the failed regeneration of new alveoli due to alveolar stem cell dysfunction might expose lung cells to elevated mechanical tension, which could activate the TGF-β signaling loop to promote the fibrotic process, especially in a periphery-to-center pattern as seen in IPF patients. Understanding the telomere-related molecular and pathophysiological mechanisms of IPF would provide new insights into IPF etiology and therapeutic strategies for this fatal disease.
Collapse
Affiliation(s)
- Kexiong Zhang
- Key Laboratory of Aging and Cancer Biology of Zhejiang Province, School of Basic Medical Sciences, Hangzhou Normal University, Hangzhou, China
| | - Lu Xu
- Key Laboratory of Aging and Cancer Biology of Zhejiang Province, School of Basic Medical Sciences, Hangzhou Normal University, Hangzhou, China
| | - Yu-Sheng Cong
- Key Laboratory of Aging and Cancer Biology of Zhejiang Province, School of Basic Medical Sciences, Hangzhou Normal University, Hangzhou, China
| |
Collapse
|
4
|
Zhang DY, Monteiro MJ, Liu JP, Gu WY. Mechanisms of cancer stem cell senescence: Current understanding and future perspectives. Clin Exp Pharmacol Physiol 2021; 48:1185-1202. [PMID: 34046925 DOI: 10.1111/1440-1681.13528] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2020] [Accepted: 05/24/2021] [Indexed: 12/13/2022]
Abstract
Cancer stem cells (CSCs) are a small population of heterogeneous tumor cells with the capacity of self-renewal and aberrant differentiation for immortality and divergent lineages of cancer cells. In contrast to bulky tumor cells, CSCs remain less differentiated and resistant to therapy even when targeted with tissue-specific antigenic markers. This makes CSCs responsible for not only tumor initiation, development, but also tumor recurrence. Emerging evidence suggests that CSCs can undergo cell senescence, a non-proliferative state of cells in response to stress. While cell senescence attenuates tumor cell proliferation, it is commonly regarded as a tumor suppressive mechanism. However, mounting research indicates that CSC senescence also provides these cells with the capacity to evade cytotoxic effects from cancer therapy, exacerbating cancer relapse and metastasis. Recent studies demonstrate that senescence drives reprogramming of cancer cell toward stemness and promotes CSC generation. In this review, we highlight the origin, heterogeneity and senescence regulatory mechanisms of CSCs, the complex relationship between CSC senescence and tumor therapy, and the recent beneficial effects of senotherapy on eliminating senescent tumor cells.
Collapse
Affiliation(s)
- Da-Yong Zhang
- Department of Clinical Medicine, Zhejiang University City College, Hangzhou, China.,Australian Institute for Bioengineering and Nanotechnology, University of Queensland, St Lucia, QLD, Australia
| | - Michael J Monteiro
- Australian Institute for Bioengineering and Nanotechnology, University of Queensland, St Lucia, QLD, Australia
| | - Jun-Ping Liu
- Institute of Ageing Research, Hangzhou Normal University, Hangzhou, China.,Department of Immunology, Monash University Faculty of Medicine, Prahran, Vic, Australia.,Hudson Institute of Medical Research, and Department of Molecular and Translational Science, Monash University Faculty of Medicine, Clayton, Vic, Australia
| | - Wen-Yi Gu
- Australian Institute for Bioengineering and Nanotechnology, University of Queensland, St Lucia, QLD, Australia
| |
Collapse
|
5
|
Arun P, Rossetti F, Wilder DM, Sajja S, Van Albert SA, Wang Y, Gist ID, Long JB. Blast Exposure Leads to Accelerated Cellular Senescence in the Rat Brain. Front Neurol 2020; 11:438. [PMID: 32508743 PMCID: PMC7253679 DOI: 10.3389/fneur.2020.00438] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2020] [Accepted: 04/24/2020] [Indexed: 12/22/2022] Open
Abstract
Blast-induced traumatic brain injury (bTBI) is one of the major causes of persistent disabilities in Service Members, and a history of bTBI has been identified as a primary risk factor for developing age-associated neurodegenerative diseases. Clinical observations of several military blast casualties have revealed a rapid age-related loss of white matter integrity in the brain. In the present study, we have tested the effect of single and tightly coupled repeated blasts on cellular senescence in the rat brain. Isoflurane-anesthetized rats were exposed to either a single or 2 closely coupled blasts in an advanced blast simulator. Rats were euthanized and brains were collected at 24 h, 1 month and 1 year post-blast to determine senescence-associated-β-galactosidase (SA-β-gal) activity in the cells using senescence marker stain. Single and repeated blast exposures resulted in significantly increased senescence marker staining in several neuroanatomical structures, including cortex, auditory cortex, dorsal lateral thalamic nucleus, geniculate nucleus, superior colliculus, ventral thalamic nucleus and hippocampus. In general, the increases in SA-β-gal activity were more pronounced at 1 month than at 24 h or 1 year post-blast and were also greater after repeated than single blast exposures. Real-time quantitative RT-PCR analysis revealed decreased levels of mRNA for senescence marker protein-30 (SMP-30) and increased mRNA levels for p21 (cyclin dependent kinase inhibitor 1A, CDKN1A), two other related protein markers of cellular senescence. The increased senescence observed in some of these affected brain structures may be implicated in several long-term sequelae after exposure to blast, including memory disruptions and impairments in movement, auditory and ocular functions.
Collapse
Affiliation(s)
- Peethambaran Arun
- Blast-Induced Neurotrauma Branch, Center for Military Psychiatry and Neuroscience, Walter Reed Army Institute of Research, Silver Spring, MD, United States
| | - Franco Rossetti
- Blast-Induced Neurotrauma Branch, Center for Military Psychiatry and Neuroscience, Walter Reed Army Institute of Research, Silver Spring, MD, United States
| | - Donna M Wilder
- Blast-Induced Neurotrauma Branch, Center for Military Psychiatry and Neuroscience, Walter Reed Army Institute of Research, Silver Spring, MD, United States
| | - Sujith Sajja
- Blast-Induced Neurotrauma Branch, Center for Military Psychiatry and Neuroscience, Walter Reed Army Institute of Research, Silver Spring, MD, United States
| | - Stephen A Van Albert
- Blast-Induced Neurotrauma Branch, Center for Military Psychiatry and Neuroscience, Walter Reed Army Institute of Research, Silver Spring, MD, United States
| | - Ying Wang
- Blast-Induced Neurotrauma Branch, Center for Military Psychiatry and Neuroscience, Walter Reed Army Institute of Research, Silver Spring, MD, United States
| | - Irene D Gist
- Blast-Induced Neurotrauma Branch, Center for Military Psychiatry and Neuroscience, Walter Reed Army Institute of Research, Silver Spring, MD, United States
| | - Joseph B Long
- Blast-Induced Neurotrauma Branch, Center for Military Psychiatry and Neuroscience, Walter Reed Army Institute of Research, Silver Spring, MD, United States
| |
Collapse
|
6
|
Ferrucci L, Gonzalez‐Freire M, Fabbri E, Simonsick E, Tanaka T, Moore Z, Salimi S, Sierra F, de Cabo R. Measuring biological aging in humans: A quest. Aging Cell 2020; 19:e13080. [PMID: 31833194 PMCID: PMC6996955 DOI: 10.1111/acel.13080] [Citation(s) in RCA: 313] [Impact Index Per Article: 78.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2019] [Revised: 10/22/2019] [Accepted: 10/27/2019] [Indexed: 12/16/2022] Open
Abstract
The global population of individuals over the age of 65 is growing at an unprecedented rate and is expected to reach 1.6 billion by 2050. Most older individuals are affected by multiple chronic diseases, leading to complex drug treatments and increased risk of physical and cognitive disability. Improving or preserving the health and quality of life of these individuals is challenging due to a lack of well-established clinical guidelines. Physicians are often forced to engage in cycles of "trial and error" that are centered on palliative treatment of symptoms rather than the root cause, often resulting in dubious outcomes. Recently, geroscience challenged this view, proposing that the underlying biological mechanisms of aging are central to the global increase in susceptibility to disease and disability that occurs with aging. In fact, strong correlations have recently been revealed between health dimensions and phenotypes that are typical of aging, especially with autophagy, mitochondrial function, cellular senescence, and DNA methylation. Current research focuses on measuring the pace of aging to identify individuals who are "aging faster" to test and develop interventions that could prevent or delay the progression of multimorbidity and disability with aging. Understanding how the underlying biological mechanisms of aging connect to and impact longitudinal changes in health trajectories offers a unique opportunity to identify resilience mechanisms, their dynamic changes, and their impact on stress responses. Harnessing how to evoke and control resilience mechanisms in individuals with successful aging could lead to writing a new chapter in human medicine.
Collapse
Affiliation(s)
- Luigi Ferrucci
- Translational Gerontology BranchBiomedical Research CenterNational Institute on AgingNational Institutes of HealthBaltimoreMDUSA
| | - Marta Gonzalez‐Freire
- Translational Gerontology BranchBiomedical Research CenterNational Institute on AgingNational Institutes of HealthBaltimoreMDUSA
| | - Elisa Fabbri
- Translational Gerontology BranchBiomedical Research CenterNational Institute on AgingNational Institutes of HealthBaltimoreMDUSA
- Department of Medical and Surgical SciencesUniversity of BolognaBolognaItaly
| | - Eleanor Simonsick
- Translational Gerontology BranchBiomedical Research CenterNational Institute on AgingNational Institutes of HealthBaltimoreMDUSA
| | - Toshiko Tanaka
- Translational Gerontology BranchBiomedical Research CenterNational Institute on AgingNational Institutes of HealthBaltimoreMDUSA
| | - Zenobia Moore
- Translational Gerontology BranchBiomedical Research CenterNational Institute on AgingNational Institutes of HealthBaltimoreMDUSA
| | - Shabnam Salimi
- Department of Epidemiology and Public HealthUniversity of Maryland School of MedicineBaltimoreMDUSA
| | - Felipe Sierra
- Division of Aging BiologyNational Institute on AgingNIHBethesdaMDUSA
| | - Rafael de Cabo
- Translational Gerontology BranchBiomedical Research CenterNational Institute on AgingNational Institutes of HealthBaltimoreMDUSA
| |
Collapse
|
7
|
Higuchi S, Miyamoto T, Kobara H, Yamada S, Asaka R, Kikuchi N, Kashima H, Ohira S, Shiozawa T. Trophoblast type-specific expression of senescence markers in the human placenta. Placenta 2019; 85:56-62. [DOI: 10.1016/j.placenta.2019.06.377] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/09/2018] [Revised: 05/16/2019] [Accepted: 06/21/2019] [Indexed: 01/05/2023]
|
8
|
Abstract
The accumulation of 'senescent' cells has long been proposed to act as an ageing mechanism. These cells display a radically altered transcriptome and degenerative phenotype compared with their growing counterparts. Tremendous progress has been made in recent years both in understanding the molecular mechanisms controlling entry into the senescent state and in the direct demonstration that senescent cells act as causal agents of mammalian ageing. The challenges now are to gain a better understanding of how the senescent cell phenotype varies between different individuals and tissues, discover how senescence predisposes to organismal frailty, and develop mechanisms by which the deleterious effects of senescent cells can be ameliorated.
Collapse
Affiliation(s)
- Richard Ga Faragher
- Stress, Ageing and Disease Research Group, School of Pharmacy & Biomolecular Sciences, University of Brighton, Brighton, East Sussex, UK
| | - Anne McArdle
- Institute of Ageing and Chronic Disease, University of Liverpool, Liverpool, UK
| | - Alison Willows
- Stress, Ageing and Disease Research Group, School of Pharmacy & Biomolecular Sciences, University of Brighton, Brighton, East Sussex, UK
| | - Elizabeth L Ostler
- Stress, Ageing and Disease Research Group, School of Pharmacy & Biomolecular Sciences, University of Brighton, Brighton, East Sussex, UK
| |
Collapse
|
9
|
Hsu YM, Yin MC. EPA or DHA enhanced oxidative stress and aging protein expression in brain of d-galactose treated mice. Biomedicine (Taipei) 2016; 6:17. [PMID: 27514534 PMCID: PMC4980825 DOI: 10.7603/s40681-016-0017-1] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2016] [Accepted: 06/20/2016] [Indexed: 11/06/2022] Open
Abstract
BACKGROUND Effects of eicosapentaenoic acid (EPA, 20:5) and docosahexaenoic acid (DHA, 22:6) upon fatty acid composition, oxidative and inflammatory factors and aging proteins in brain of d-galactose (DG) treated aging mice were examined. METHODS Each fatty acid at 7 mg/kg BW/week was supplied for 8 weeks. Brain aging was induced by DG treatment (100 mg/kg body weight) via daily subcutaneous injection for 8 weeks. RESULTS DG, EPA and DHA treatments changed brain fatty acid composition. DG down-regulated brain Bcl-2 expression and up-regulated Bax expression. Compared with DG groups, EPA and DHA further enhanced Bax expression. DG decreased glutathione content, increased reactive oxygen species (ROS) and oxidized glutathione (GSSG) production, the intake of EPA or DHA caused greater ROS and GSSG formation. DG treatments up-regulated the protein expression of p47(phox) and gp91(phox), and the intake of EPA or DHA led to greater p47(phox) and gp91(phox) expression. DG increased brain prostaglandin E2 (PGE2) levels, and cyclooxygenase (COX)-2 expression and activity, the intake of EPA or DHA reduced brain COX-2 activity and PGE2 formation. DG enhanced brain p53, p16 and p21 expression. EPA and DHA intake led to greater p21 expression, and EPA only caused greater p53 and p16 expression. CONCLUSION These findings suggest that these two PUFAs have toxic effects toward aging brain.
Collapse
Affiliation(s)
- Yuan-Man Hsu
- Department of Biological Science and Technology, China Medical University, 404, Taichung, Taiwan
| | - Mei-Chin Yin
- Department of Nutrition, China Medical University, 91, Hsueh-shih Rd., 404, Taichung, Taiwan.
| |
Collapse
|
10
|
Kipkeew F, Kirsch M, Klein D, Wuelling M, Winterhager E, Gellhaus A. CCN1 (CYR61) and CCN3 (NOV) signaling drives human trophoblast cells into senescence and stimulates migration properties. Cell Adh Migr 2016; 10:163-78. [PMID: 26744771 DOI: 10.1080/19336918.2016.1139265] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
During placental development, continuous invasion of trophoblasts into the maternal compartment depends on the support of proliferating extravillous trophoblasts (EVTs). Unlike tumor cells, EVTs escape from the cell cycle before invasion into the decidua and spiral arteries. This study focused on the regulation properties of glycosylated and non-glycosylated matricellular CCN1 and CCN3, primarily for proliferation control in the benign SGHPL-5 trophoblast cell line, which originates from the first-trimester placenta. Treating SGHPL-5 trophoblast cells with the glycosylated forms of recombinant CCN1 and CCN3 decreased cell proliferation by bringing about G0/G1 cell cycle arrest, which was accompanied by the upregulation of activated Notch-1 and its target gene p21. Interestingly, both CCN proteins increased senescence-associated β-galactosidase activity and the expression of the senescence marker p16. The migration capability of SGHPL-5 cells was mostly enhanced in response to CCN1 and CCN3, by the activation of FAK and Akt kinase but not by the activation of ERK1/2. In summary, both CCN proteins play a key role in regulating trophoblast cell differentiation by inducing senescence and enhancing migration properties. Reduced levels of CCN1 and CCN3, as found in early-onset preeclampsia, could contribute to a shift from invasive to proliferative EVTs and may explain their shallow invasion properties in this disease.
Collapse
Affiliation(s)
- Friederike Kipkeew
- a Department of Molecular Biology , University of Duisburg-Essen , Essen , Germany
| | - Manuela Kirsch
- b Department of Gynecology and Obstetrics , University of Duisburg-Essen , Essen , Germany
| | - Diana Klein
- c Institute of Cell Biology, University of Duisburg-Essen , Essen , Germany
| | - Manuela Wuelling
- d Department of Developmental Biology , University of Duisburg-Essen , Essen , Germany
| | - Elke Winterhager
- a Department of Molecular Biology , University of Duisburg-Essen , Essen , Germany
| | - Alexandra Gellhaus
- a Department of Molecular Biology , University of Duisburg-Essen , Essen , Germany.,b Department of Gynecology and Obstetrics , University of Duisburg-Essen , Essen , Germany
| |
Collapse
|
11
|
Burton DGA, Faragher RGA. Cellular senescence: from growth arrest to immunogenic conversion. AGE (DORDRECHT, NETHERLANDS) 2015; 37:27. [PMID: 25787341 PMCID: PMC4365077 DOI: 10.1007/s11357-015-9764-2] [Citation(s) in RCA: 66] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2014] [Accepted: 02/27/2015] [Indexed: 05/23/2023]
Abstract
Cellular senescence was first reported in human fibroblasts as a state of stable in vitro growth arrest following extended culture. Since that initial observation, a variety of other phenotypic characteristics have been shown to co-associate with irreversible cell cycle exit in senescent fibroblasts. These include (1) a pro-inflammatory secretory response, (2) the up-regulation of immune ligands, (3) altered responses to apoptotic stimuli and (4) promiscuous gene expression (stochastic activation of genes possibly as a result of chromatin remodeling). Many features associated with senescent fibroblasts appear to promote conversion to an immunogenic phenotype that facilitates self-elimination by the immune system. Pro-inflammatory cytokines can attract and activate immune cells, the presentation of membrane bound immune ligands allows for specific recognition and promiscuous gene expression may function to generate an array of tissue restricted proteins that could subsequently be processed into peptides for presentation via MHC molecules. However, the phenotypes of senescent cells from different tissues and species are often assumed to be broadly similar to those seen in senescent human fibroblasts, but the data show a more complex picture in which the growth arrest mechanism, tissue of origin and species can all radically modulate this basic pattern. Furthermore, well-established triggers of cell senescence are often associated with a DNA damage response (DDR), but this may not be a universal feature of senescent cells. As such, we discuss the role of DNA damage in regulating an immunogenic response in senescent cells, in addition to discussing less established "atypical" senescent states that may occur independent of DNA damage.
Collapse
Affiliation(s)
- D. G. A. Burton
- Department of Molecular Cell Biology, The Weizmann Institute of Science, 76100 Rehovot, Israel
| | - R. G. A. Faragher
- School of Pharmacy & Biomolecular Science, University of Brighton, Huxley Building, Brighton, UK
| |
Collapse
|