401
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Servais C, Erez N. From sentinel cells to inflammatory culprits: cancer-associated fibroblasts in tumour-related inflammation. J Pathol 2012; 229:198-207. [DOI: 10.1002/path.4103] [Citation(s) in RCA: 116] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2012] [Revised: 08/27/2012] [Accepted: 09/07/2012] [Indexed: 12/11/2022]
Affiliation(s)
- Charlotte Servais
- Department of Pathology, Sackler School of Medicine; Tel Aviv University; Tel-Aviv Israel 69978
| | - Neta Erez
- Department of Pathology, Sackler School of Medicine; Tel Aviv University; Tel-Aviv Israel 69978
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402
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1 0 7. Cancer Biomark 2012. [DOI: 10.1201/b14318-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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403
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Abstract
For most species, aging promotes a host of degenerative pathologies that are characterized by debilitating losses of tissue or cellular function. However, especially among vertebrates, aging also promotes hyperplastic pathologies, the most deadly of which is cancer. In contrast to the loss of function that characterizes degenerating cells and tissues, malignant (cancerous) cells must acquire new (albeit aberrant) functions that allow them to develop into a lethal tumor. This review discusses the idea that, despite seemingly opposite characteristics, the degenerative and hyperplastic pathologies of aging are at least partly linked by a common biological phenomenon: a cellular stress response known as cellular senescence. The senescence response is widely recognized as a potent tumor suppressive mechanism. However, recent evidence strengthens the idea that it also drives both degenerative and hyperplastic pathologies, most likely by promoting chronic inflammation. Thus, the senescence response may be the result of antagonistically pleiotropic gene action.
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Affiliation(s)
- Judith Campisi
- Buck Institute for Research on Aging, Novato, California 94945, USA.
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404
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Sikora E. Rejuvenation of senescent cells-the road to postponing human aging and age-related disease? Exp Gerontol 2012; 48:661-6. [PMID: 23064316 DOI: 10.1016/j.exger.2012.09.008] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2012] [Revised: 09/19/2012] [Accepted: 09/20/2012] [Indexed: 12/15/2022]
Abstract
Cellular senescence is the state of permanent inhibition of cell proliferation. Replicative senescence occurs due to the end replication problem and shortening telomeres with each cell division leading to DNA damage response (DDR). The number of short telomeres increases with age and age-related pathologies. Stress induced senescence, although not accompanied by attrition of telomeres, is also attributed to the DDR induced by irreparable DNA lesions in telomeric DNA. Senescent cells characterized by the presence of γH2AX, the common marker of double DNA strand breaks, and other senescence markers including activity of SA-β-gal, accumulate in tissues of aged animals and humans as well as at sites of pathology. It is believed that cellular senescence evolved as a cancer barrier since non-proliferating senescent cells cannot be transformed to neoplastic cells. On the other hand senescent cells favor cancer development, just like other age-related pathologies, by creating a low grade inflammatory state due to senescence associated secretory phenotype (SASP). Reversal/inhibition of cellular senescence could prolong healthy life span, thus many attempts have been undertaken to influence cellular senescence. The two main approaches are genetic and pharmacological/nutritional modifications of cell fate. The first one concerns cell reprogramming by induced pluripotent stem cells (iPSCs), which in vitro is effective even in cells undergoing senescence, or derived from very old or progeroid patients. The second approach concerns modification of senescence signaling pathways just like TOR-induced by pharmacological or with natural agents. However, knowing that aging is unavoidable we cannot expect its elimination, but prolonging healthy life span is a goal worth serious consideration.
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Affiliation(s)
- Ewa Sikora
- Laboratory of the Molecular Bases of Aging, Nencki Institute of Experimental Biology, Polish Academy of Sciences, Pasteura 3, Warsaw, Poland.
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405
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Cirri P, Chiarugi P. Cancer-associated-fibroblasts and tumour cells: a diabolic liaison driving cancer progression. Cancer Metastasis Rev 2012; 31:195-208. [PMID: 22101652 DOI: 10.1007/s10555-011-9340-x] [Citation(s) in RCA: 366] [Impact Index Per Article: 30.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Several recent papers have now provided compelling experimental evidence that the progression of tumours towards a malignant phenotype does not depend exclusively on the cell-autonomous properties of cancer cells themselves but is also deeply influenced by tumour stroma reactivity, thereby undergoing a strict environmental control. Tumour microenvironmental elements include structural components such as the extracellular matrix or hypoxia as well as stromal cells, either resident cells or recruited from circulating precursors, as macrophages and other inflammatory cells, endothelial cells and cancer-associated fibroblasts (CAFs). All these elements synergistically play a specific role in cancer progression. This review summarizes our current knowledge on the role of CAFs in tumour progression, with a particular focus on the biunivocal interplay between CAFs and cancer cells leading to the activation of the epithelial-mesenchymal transition programme and the achievement of stem cell traits, as well as to the metabolic reprogramming of both stromal and cancer cells. Recent advances on the role of CAFs in the preparation of metastatic niche, as well as the controversial origin of CAFs, are discussed in light of the new emerging therapeutic implications of targeting CAFs.
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Affiliation(s)
- Paolo Cirri
- Department of Biochemical Science, University of Florence, Florence, Italy
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406
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Abstract
Aging is the main risk factor for Alzheimer’s disease (AD); however, the aspects of the aging process that predispose the brain to the development of AD are largely unknown. Astrocytes perform a myriad of functions in the central nervous system to maintain homeostasis and support neuronal function. In vitro, human astrocytes are highly sensitive to oxidative stress and trigger a senescence program when faced with multiple types of stress. In order to determine whether senescent astrocytes appear in vivo, brain tissue from aged individuals and patients with AD was examined for the presence of senescent astrocytes using p16INK4a and matrix metalloproteinase-1 (MMP-1) expression as markers of senescence. Compared with fetal tissue samples (n = 4), a significant increase in p16INK4a-positive astrocytes was observed in subjects aged 35 to 50 years (n = 6; P = 0.02) and 78 to 90 years (n = 11; P<10−6). In addition, the frontal cortex of AD patients (n = 15) harbored a significantly greater burden of p16INK4a-positive astrocytes compared with non-AD adult control subjects of similar ages (n = 25; P = 0.02) and fetal controls (n = 4; P<10−7). Consistent with the senescent nature of the p16INK4a-positive astrocytes, increased metalloproteinase MMP-1 correlated with p16INK4a. In vitro, beta-amyloid 1–42 (Aβ1–42) triggered senescence, driving the expression of p16INK4a and senescence-associated beta-galactosidase. In addition, we found that senescent astrocytes produce a number of inflammatory cytokines including interleukin-6 (IL-6), which seems to be regulated by p38MAPK. We propose that an accumulation of p16INK4a-positive senescent astrocytes may link increased age and increased risk for sporadic AD.
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407
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Cadenas C, Vosbeck S, Hein EM, Hellwig B, Langer A, Hayen H, Franckenstein D, Büttner B, Hammad S, Marchan R, Hermes M, Selinski S, Rahnenführer J, Peksel B, Török Z, Vígh L, Hengstler JG. Glycerophospholipid profile in oncogene-induced senescence. Biochim Biophys Acta Mol Cell Biol Lipids 2012; 1821:1256-68. [DOI: 10.1016/j.bbalip.2011.11.008] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2011] [Revised: 11/14/2011] [Accepted: 11/17/2011] [Indexed: 11/27/2022]
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408
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Scarpulla RC, Vega RB, Kelly DP. Transcriptional integration of mitochondrial biogenesis. Trends Endocrinol Metab 2012; 23:459-66. [PMID: 22817841 PMCID: PMC3580164 DOI: 10.1016/j.tem.2012.06.006] [Citation(s) in RCA: 568] [Impact Index Per Article: 47.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/03/2012] [Revised: 06/15/2012] [Accepted: 06/19/2012] [Indexed: 02/06/2023]
Abstract
Gene regulatory factors encoded by the nuclear genome are essential for mitochondrial biogenesis and function. Some of these factors act exclusively within the mitochondria to regulate the control of mitochondrial transcription, translation, and other functions. Others govern the expression of nuclear genes required for mitochondrial metabolism and organelle biogenesis. The peroxisome proliferator-activated receptor γ coactivator-1 (PGC-1) family of transcriptional coactivators play a major role in transducing and integrating physiological signals governing metabolism, differentiation, and cell growth to the transcriptional machinery controlling mitochondrial functional capacity. Thus, the PGC-1 coactivators serve as a central component of the transcriptional regulatory circuitry that coordinately controls the energy-generating functions of mitochondria in accordance with the metabolic demands imposed by changing physiological conditions, senescence, and disease.
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Affiliation(s)
- Richard C Scarpulla
- Department of Cell and Molecular Biology, Northwestern University Medical School, Chicago, IL 60611, USA
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409
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Laberge RM, Zhou L, Sarantos MR, Rodier F, Freund A, de Keizer PL, Liu S, Demaria M, Cong YS, Kapahi P, Desprez PY, Hughes RE, Campisi J. Glucocorticoids suppress selected components of the senescence-associated secretory phenotype. Aging Cell 2012; 11:569-78. [PMID: 22404905 PMCID: PMC3387333 DOI: 10.1111/j.1474-9726.2012.00818.x] [Citation(s) in RCA: 154] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Cellular senescence suppresses cancer by arresting the proliferation of cells at risk for malignant transformation. Recently, senescent cells were shown to secrete numerous cytokines, growth factors, and proteases that can alter the tissue microenvironment and may promote age-related pathology. To identify small molecules that suppress the senescence-associated secretory phenotype (SASP), we developed a screening protocol using normal human fibroblasts and a library of compounds that are approved for human use. Among the promising library constituents was the glucocorticoid corticosterone. Both corticosterone and the related glucocorticoid cortisol decreased the production and secretion of selected SASP components, including several pro-inflammatory cytokines. Importantly, the glucocorticoids suppressed the SASP without reverting the tumor suppressive growth arrest and were efficacious whether cells were induced to senesce by ionizing radiation or strong mitogenic signals delivered by oncogenic RAS or MAP kinase kinase 6 overexpression. Suppression of the prototypical SASP component IL-6 required the glucocorticoid receptor, which, in the presence of ligand, inhibited IL-1α signaling and NF-κB transactivation activity. Accordingly, co-treatments combining glucocorticoids with the glucocorticoid antagonist RU-486 or recombinant IL-1α efficiently reestablished NF-κB transcriptional activity and IL-6 secretion. Our findings demonstrate feasibility of screening for compounds that inhibit the effects of senescent cells. They further show that glucocorticoids inhibit selected components of the SASP and suggest that corticosterone and cortisol, two FDA-approved drugs, might exert their effects in part by suppressing senescence-associated inflammation.
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Affiliation(s)
- Remi-Martin Laberge
- Buck Institute for Research on Aging, 8001 Redwood Boulevard, Novato, CA 94945, USA
| | - Lili Zhou
- Buck Institute for Research on Aging, 8001 Redwood Boulevard, Novato, CA 94945, USA
- Institute of Cell Biology, College of Life Sciences, Beijing Normal University, Beijing, China 100875
| | - Melissa R. Sarantos
- Buck Institute for Research on Aging, 8001 Redwood Boulevard, Novato, CA 94945, USA
| | - Francis Rodier
- Centre de Recherche du Centre Hospitalier de l’Université de Montréal (CRCHUM)/Institut du Cancer de Montréal, Department of Radiology, Radio-Oncology and Nuclear Medicine, Université de Montréal, Montréal, QC H2L 4M1, Canada
| | - Adam Freund
- Buck Institute for Research on Aging, 8001 Redwood Boulevard, Novato, CA 94945, USA
| | - Peter L.J. de Keizer
- Buck Institute for Research on Aging, 8001 Redwood Boulevard, Novato, CA 94945, USA
| | - Su Liu
- Buck Institute for Research on Aging, 8001 Redwood Boulevard, Novato, CA 94945, USA
| | - Marco Demaria
- Buck Institute for Research on Aging, 8001 Redwood Boulevard, Novato, CA 94945, USA
| | - Yu-Sheng Cong
- Institute of Cell Biology, College of Life Sciences, Beijing Normal University, Beijing, China 100875
| | - Pankaj Kapahi
- Buck Institute for Research on Aging, 8001 Redwood Boulevard, Novato, CA 94945, USA
| | - Pierre-Yves Desprez
- Buck Institute for Research on Aging, 8001 Redwood Boulevard, Novato, CA 94945, USA
- California Pacific Medical Center, Research Institute, 475 Brannan Street, San Francisco, CA 94107, USA
| | - Robert E. Hughes
- Buck Institute for Research on Aging, 8001 Redwood Boulevard, Novato, CA 94945, USA
| | - Judith Campisi
- Buck Institute for Research on Aging, 8001 Redwood Boulevard, Novato, CA 94945, USA
- Lawrence Berkeley National Laboratory, Life Sciences Division, 1 Cyclotron Road, Berkeley, CA 94720, USA
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410
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Kim KC, Kang KA, Lim CM, Park JH, Jung KS, Hyun JW. Water extract of edible bird’s nest attenuated the oxidative stress-induced matrix metalloproteinase-1 by regulating the mitogen-activated protein kinase and activator protein-1 pathway in human keratinocytes. ACTA ACUST UNITED AC 2012. [DOI: 10.1007/s13765-012-2030-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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411
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Abstract
A major goal in cancer and aging research is to discriminate the biochemical modifications that happen locally that could account for the healthiness or malignancy of tissues. Senescence is one general antiproliferative cellular process that acts as a strong barrier for cancer progression, playing a crucial role in aging. Here, we focus on the current methods to assess cellular senescence, discriminating the advantages and disadvantages of several senescence biomarkers.
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Affiliation(s)
- Bruno Bernardes de Jesus
- Telomeres and Telomerase Group, Molecular Oncology Program, Spanish National Cancer Centre, Madrid, Spain
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412
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Deeks SG, Verdin E, McCune JM. Immunosenescence and HIV. Curr Opin Immunol 2012; 24:501-6. [PMID: 22658763 DOI: 10.1016/j.coi.2012.05.004] [Citation(s) in RCA: 109] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2012] [Revised: 05/05/2012] [Accepted: 05/10/2012] [Indexed: 01/07/2023]
Abstract
PURPOSE OF REVIEW The present review discusses the interplay between HIV infection and other environmental factors (e.g. co-infection with CMV) in the acceleration of the aging process of the immune system, leading to 'immunosenescence.' RECENT FINDINGS Basic studies in cell biology demonstrate that replicative senescence is a common pathway of many cell lineages, including those of the immune system, characterized by activation of a unique pro-inflammatory secretory program. In the setting of HIV disease, this process is accelerated, resulting in an immunosuppressed state that diminishes the ability of the immune system to contain virus while at the same time facilitating viral replication and spread. Clinically, these changes result in a lower capacity to respond to new infections as well as an increased frequency of age-associated end-organ disease (e.g. cardiovascular complications, cancer, and neurologic disease). SUMMARY Accelerated immunosenescence in the setting of HIV disease is associated with increased morbidity and mortality, prompting the need for more investigation into its causes, diagnosis, and treatment.
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Affiliation(s)
- Steven G Deeks
- HIV/AIDS Program, Department of Medicine, University of California, San Francisco, CA, USA
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413
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Accelerated senescence of renal tubular epithelial cells is associated with disease progression of patients with immunoglobulin A (IgA) nephropathy. Transl Res 2012; 159:454-63. [PMID: 22633096 DOI: 10.1016/j.trsl.2011.11.008] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/07/2011] [Revised: 11/29/2011] [Accepted: 11/29/2011] [Indexed: 11/22/2022]
Abstract
The aim of this study is to determine the potential correlation between the accelerated senescence of renal tubular epithelial cells (RTECs) and the disease progression of patients with immunoglobulin A nephropathy (IgAN). A total of 108 IgAN patients with different Lee's pathologic grades were enrolled. Additionally, 18 patients with renal resection were recruited as controls. Cellular senescence was evaluated by senescence-associated β-galactosidase (SA-β-gal) staining and an immunohistochemical analysis of p21 and p16 protein expression. The expression of type III collagen (Col III) and fibronectin (FN) in renal interstitium and the levels of serum total and low-density lipoprotein (LDL) cholesterol, serum creatinine concentration (SCr), and 24-h urinary protein excretion were evaluated also. SA-β-gal staining and the expression of p16 and p21 were increased significantly in renal biopsy specimens obtained from grades I-II IgAN patients compared with controls (P < 0.05). The expression of these senescence-associated markers increased gradually with disease progression and correlated with the renal morphologic changes and the expression of Col III and FN in renal interstitium in IgAN patients. A correlation analysis showed that the expressions of p16, p21, and SA-β-gal staining were associated significantly with blood pressure and renal function (P < 0.05), but not with patient age, body mass index (BMI), LDL cholesterol level, or 24-h urinary protein value (P > 0.05). Our results indicated that the RTECs in IgAN patients exhibited features of accelerated senescence, which were unrelated to mechanisms associated with normal aging. Cellular senescence was associated closely with IgAN disease progression, which suggested the accelerated senescence of RTECs may contribute to this progression.
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414
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Giannoni E, Parri M, Chiarugi P. EMT and oxidative stress: a bidirectional interplay affecting tumor malignancy. Antioxid Redox Signal 2012; 16:1248-63. [PMID: 21929373 DOI: 10.1089/ars.2011.4280] [Citation(s) in RCA: 155] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
SIGNIFICANCE Epithelial-mesenchymal transition (EMT) is emerging as a driving force in tumor progression, enabling cancer cells to evade their "homeland" and to colonize remote locations. In this review, we focus on the emerging views dealing with a redox control of EMT and with the importance of a pro-oxidant environment, both in cancer and stromal cells, to attain an improvement in tumor malignancy. RECENT ADVANCES The variety of signals able to promote EMT is large and continuously growing, ranging from soluble factors to components of the extracellular matrix. Compelling evidence highlights reactive oxygen species (ROS) as crucial conspirators in EMT engagement. CRITICAL ISSUES Tumor microenvironment exploits a fascinating role in ensuring EMT outcome within the primary tumor, granting for the achievement of an essential selective advantage for cancer cells. Cancer-associated fibroblasts, macrophages, and hypoxia are major players in this scenario, exerting a propelling role for EMT, as well as for invasiveness, stemness, and dissemination of metastatic cells. FUTURE DIRECTIONS Future research focused on EMT should address some key points that are still unclear. They include: i) the role of the reverse phenomenon (i.e., mesenchymal-epithelial transition) that is likely regulated in the final stages of tumor progression, or that of mesenchymal-amoeboid transition, a plasticity program of cancer cells, which often follows EMT and offers a further metastatic advantage, and ii) the molecular basis of the correlation between stemness, EMT and ROS content.
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Affiliation(s)
- Elisa Giannoni
- Department of Biochemical Sciences, University of Florence, Tuscany Tumor Institute, and Center for Research, Transfer and High Education DenoTHE, Florence, Italy.
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415
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The quiescent cellular state is Arf/p53-dependent and associated with H2AX downregulation and genome stability. Int J Mol Sci 2012; 13:6492-6506. [PMID: 22754379 PMCID: PMC3382772 DOI: 10.3390/ijms13056492] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2012] [Revised: 05/21/2012] [Accepted: 05/22/2012] [Indexed: 12/17/2022] Open
Abstract
Cancer is a disease associated with genomic instability and mutations. Excluding some tumors with specific chromosomal translocations, most cancers that develop at an advanced age are characterized by either chromosomal or microsatellite instability. However, it is still unclear how genomic instability and mutations are generated during the process of cellular transformation and how the development of genomic instability contributes to cellular transformation. Recent studies of cellular regulation and tetraploidy development have provided insights into the factors triggering cellular transformation and the regulatory mechanisms that protect chromosomes from genomic instability.
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416
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Oxidative stress, tumor microenvironment, and metabolic reprogramming: a diabolic liaison. Int J Cell Biol 2012; 2012:762825. [PMID: 22666258 PMCID: PMC3361160 DOI: 10.1155/2012/762825] [Citation(s) in RCA: 200] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2012] [Accepted: 03/06/2012] [Indexed: 12/11/2022] Open
Abstract
Conversely to normal cells, where deregulated oxidative stress drives the activation of death pathways, malignant cells exploit oxidative milieu for its advantage. Cancer cells are located in a very complex microenvironment together with stromal components that participate to enhance oxidative stress to promote tumor progression. Indeed, convincing experimental and clinical evidence underline the key role of oxidative stress in several tumor aspects thus affecting several characteristics of cancer cells. Oxidants influence the DNA mutational potential, intracellular signaling pathways controlling cell proliferation and survival and cell motility and invasiveness as well as control the reactivity of stromal components that is fundamental for cancer development and dissemination, inflammation, tissue repair, and de novo angiogenesis. This paper is focused on the role of oxidant species in the acquisition of two mandatory features for aggressive neoplastic cells, recently defined by Hanahan and Weinberg as new “hallmarks of cancer”: tumor microenvironment and metabolic reprogramming of cancer cells.
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417
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Yoon JY, Lafarge S, Dawe D, Lakhi S, Kumar R, Morales C, Marshall A, Gibson SB, Johnston JB. Association of interleukin-6 and interleukin-8 with poor prognosis in elderly patients with chronic lymphocytic leukemia. Leuk Lymphoma 2012; 53:1735-42. [DOI: 10.3109/10428194.2012.666662] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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418
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Dale W, Mohile SG, Eldadah BA, Trimble EL, Schilsky RL, Cohen HJ, Muss HB, Schmader KE, Ferrell B, Extermann M, Nayfield SG, Hurria A. Biological, clinical, and psychosocial correlates at the interface of cancer and aging research. J Natl Cancer Inst 2012; 104:581-9. [PMID: 22457474 DOI: 10.1093/jnci/djs145] [Citation(s) in RCA: 82] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
In September 2010, the Cancer and Aging Research Group, in collaboration with the National Cancer Institute and the National Institute on Aging, conducted the first of three planned conferences to discuss research methodology to generate the highest quality research in older adults with cancer and then disseminate these findings among those working in the fields of cancer and aging. Conference speakers discussed the current level of research evidence in geriatric oncology, outlined the current knowledge gaps, and put forth principles for research designs and strategies that would address these gaps within the next 10 years. It was agreed that future oncology research trials that enroll older adults should include: (1) improved standardized geriatric assessment of older oncology patients, (2) substantially enhanced biological assessment of older oncology patients, (3) specific trials for the most vulnerable and/or those older than 75 years, and (4) research infrastructure that specifically targets older adults and substantially strengthened geriatrics and oncology research collaborations. This initial conference laid the foundation for the next two meetings, which will address the research designs and collaborations needed to enhance therapeutic and intervention trials in older adults with cancer.
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Affiliation(s)
- William Dale
- Department of Medical Oncology and Therapeutics Research, City of Hope, 1500 E Duarte Rd, Duarte, CA 91010, USA
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419
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Abstract
Cellular senescence is a program of irreversible cell cycle arrest that cells undergo in response to a variety of intrinsic and extrinsic stimuli including progressive shortening of telomeres, changes in telomeric structure or other forms of genotoxic and non-genotoxic stress. The role of nuclear factor-κB in cellular senescence is controversial, as it has been associated with both proliferation and tumour progression, and also with growth arrest and ageing. This research perspective focuses on the evidence for a functional relationship between NF-κB and senescence, and how disruption of the NF-κB pathway can lead to its bypass.
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Affiliation(s)
- Simon Vaughan
- Department of Neurodegenerative Disease, UCL Institute of Neurology, Queen Square, London, UK
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420
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Liu J, Xu K, Chase M, Ji Y, Logan JK, Buchsbaum RJ. Tiam1-regulated osteopontin in senescent fibroblasts contributes to the migration and invasion of associated epithelial cells. J Cell Sci 2012; 125:376-86. [PMID: 22302986 DOI: 10.1242/jcs.089466] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
The tumor microenvironment undergoes changes concurrent with neoplastic progression. Cancer incidence increases with aging and is associated with tissue accumulation of senescent cells. Senescent fibroblasts are thought to contribute to tumor development in aging tissues. We have shown that fibroblasts deficient in the Rac exchange factor Tiam1 promote invasion and metastasis of associated epithelial tumor cells. Here, we use a three-dimensional culture model of cellular invasiveness to outline several steps underlying this effect. We find that stress-induced senescence induces decreased fibroblast Tiam1 protein levels and increased osteopontin levels, and that senescent fibroblast lysates induce Tiam1 protein degradation in a calcium- and calpain-dependent fashion. Changes in fibroblast Tiam1 protein levels induce converse changes in osteopontin mRNA and protein. Senescent fibroblasts induce increased invasion and migration in co-cultured mammary epithelial cells. These effects in epithelial cells are ameliorated by either increasing fibroblast Tiam1 or decreasing fibroblast osteopontin. Finally, in seeded cell migration assays we find that either senescent or Tiam1-deficient fibroblasts induce increased epithelial cell migration that is dependent on fibroblast secretion of osteopontin. These findings indicate that one mechanism by which senescent fibroblasts promote neoplastic progression in associated tumors is through degradation of fibroblast Tiam1 protein and the consequent increase in secretion of osteopontin by fibroblasts.
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Affiliation(s)
- Jiewei Liu
- Molecular Oncology Research Institute, Tufts Medical Center Boston, MA 02111, USA
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421
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Colorectal adenoma to carcinoma progression is accompanied by changes in gene expression associated with ageing, chromosomal instability, and fatty acid metabolism. Cell Oncol (Dordr) 2012; 35:53-63. [PMID: 22278361 PMCID: PMC3308003 DOI: 10.1007/s13402-011-0065-1] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/28/2011] [Indexed: 02/08/2023] Open
Abstract
Background Colorectal cancer develops in a multi-step manner from normal epithelium, through a pre-malignant lesion (so-called adenoma), into a malignant lesion (carcinoma), which invades surrounding tissues and eventually can spread systemically (metastasis). It is estimated that only about 5% of adenomas do progress to a carcinoma. Aim The present study aimed to unravel the biology of adenoma to carcinoma progression by mRNA expression profiling, and to identify candidate biomarkers for adenomas that are truly at high risk of progression. Methods Genome-wide mRNA expression profiles were obtained from a series of 37 colorectal adenomas and 31 colorectal carcinomas using oligonucleotide microarrays. Differentially expressed genes were validated in an independent colorectal gene expression data set. Gene Set Enrichment Analysis (GSEA) was used to identify altered expression of sets of genes associated with specific biological processes, in order to better understand the biology of colorectal adenoma to carcinoma progression. Results mRNA expression of 248 genes was significantly different, of which 96 were upregulated and 152 downregulated in carcinomas compared to adenomas. Classification of adenomas and carcinomas using the expression of these genes showed to be very accurate, also when tested in an independent expression data set. Gene-sets associated with ageing (which is related to senescence) and chromosomal instability were upregulated, and a gene-set associated with fatty acid metabolism was downregulated in carcinomas compared to adenomas. Moreover, gene-sets associated with chromosomal location revealed chromosome 4q22 loss and chromosome 20q gain of gene-set expression as being relevant in this progression. Concluding remark These data are consistent with the notion that adenomas and carcinomas are distinct biological entities. Disruption of specific biological processes like senescence (ageing), maintenance of chromosomal instability and altered metabolism, are key factors in the progression from adenoma to carcinoma. Electronic supplementary material The online version of this article (doi:10.1007/s13402-011-0065-1) contains supplementary material, which is available to authorized users.
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422
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Chilosi M, Poletti V, Rossi A. The pathogenesis of COPD and IPF: distinct horns of the same devil? Respir Res 2012; 13:3. [PMID: 22235752 PMCID: PMC3282644 DOI: 10.1186/1465-9921-13-3] [Citation(s) in RCA: 138] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2011] [Accepted: 01/11/2012] [Indexed: 01/08/2023] Open
Abstract
New paradigms have been recently proposed in the pathogenesis of both chronic obstructive pulmonary disease (COPD) and idiopathic pulmonary fibrosis (IPF), evidencing surprising similarities between these deadly diseases, despite their obvious clinical, radiological and pathologic differences. There is growing evidence supporting a "double hit" pathogenic model where in both COPD and IPF the cumulative action of an accelerated senescence of pulmonary parenchyma (determined by either telomere dysfunction and/or a variety of genetic predisposing factors), and the noxious activity of cigarette smoke-induced oxidative damage are able to severely compromise the regenerative potential of two pulmonary precursor cell compartments (alveolar epithelial precursors in IPF, mesenchymal precursor cells in COPD/emphysema). The consequent divergent derangement of signalling pathways involved in lung tissue renewal (mainly Wnt and Notch), can eventually lead to the distinct abnormal tissue remodelling and functional impairment that characterise the alveolar parenchyma in these diseases (irreversible fibrosis and bronchiolar honeycombing in IPF, emphysema and airway chronic inflammation in COPD).
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Affiliation(s)
- Marco Chilosi
- Department of Pathology, University of Verona, Italy.
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423
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MicroRNAs as a novel cellular senescence regulator. Ageing Res Rev 2012; 11:41-50. [PMID: 21689787 DOI: 10.1016/j.arr.2011.06.001] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2011] [Revised: 05/09/2011] [Accepted: 06/02/2011] [Indexed: 12/26/2022]
Abstract
Cellular senescence is a program activated in normal cells in response to various types of stresses and is manifested by permanent arrest of cell cycle. Cellular senescence is closely related to tumor suppression, and may contribute to the ageing of organisms. The complex senescence cell phenotype has many different mechanisms. Recent studies have provided important insights regarding the role played by miRNAs during cellular senescence as a novel molecular mechanism. In this article, we will review the latest advances in the identification and validation of senescence-regulatory miRNAs and the possible mechanisms.
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424
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Abstract
(Macro)autophagy is a cellular membrane trafficking process that serves to deliver cytoplasmic constituents to lysosomes for degradation. At basal levels, it is critical for maintaining cytoplasmic as well as genomic integrity and is therefore key to maintaining cellular homeostasis. Autophagy is also highly adaptable and can be modified to digest specific cargoes to bring about selective effects in response to numerous forms of intracellular and extracellular stress. It is not a surprise, therefore, that autophagy has a fundamental role in cancer and that perturbations in autophagy can contribute to malignant disease. We review here the roles of autophagy in various aspects of tumor suppression including the response of cells to nutrient and hypoxic stress, the control of programmed cell death, and the connection to tumor-associated immune responses.
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Affiliation(s)
- Li Yen Mah
- Tumour Cell Death Laboratory, Beatson Institute for Cancer Research, Glasgow G61 1BD, United Kingdom
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425
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Myers CE, Mirza NN, Lustgarten J. Immunity, cancer and aging: lessons from mouse models. Aging Dis 2011; 2:512-523. [PMID: 22396898 PMCID: PMC3295066] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2011] [Revised: 08/22/2011] [Accepted: 09/05/2011] [Indexed: 05/31/2023] Open
Abstract
The deterioration of immune function with advancing age is associated with an increased incidence of cancer. Most of the studies to evaluate the effect of immunotherapy on cancer have been conducted in the young without considering the effect of age-associated changes in immune function. Studies from my laboratory and others groups indicate that immunotherapeutic interventions could be effective in young animals, but that the same therapies are not as effective in old animals. The present review summarizes some defects found in the old immune system affecting the activation of antitumor immune responses, the strategies used to activate a more robust antitumor immune response in the old and the description of a preclinical tumor model indicating possible strategies for optimization of immunotherapeutic interventions in the old.
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Affiliation(s)
| | - Noweeda N. Mirza
- Correspondence should be addressed to: Noweeda Mirza PhD, Mayo Clinic Arizona, Scottsdale, AZ 85259, USA. . This review is dedicated to Joseph Lustgarten Ph.D. who passed away on June 30, 2011 after a short but very courageous battle with stage IV stomach adenocarcinoma
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426
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Blagosklonny MV. Molecular damage in cancer: an argument for mTOR-driven aging. Aging (Albany NY) 2011; 3:1130-41. [PMID: 22246147 PMCID: PMC3273893 DOI: 10.18632/aging.100422] [Citation(s) in RCA: 74] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2011] [Accepted: 12/31/2011] [Indexed: 12/12/2022]
Abstract
Despite common belief, accumulation of molecular damage does not play a key role in aging. Still, cancer (an age-related disease) is initiated by molecular damage. Cancer and aging share a lot in common including the activation of the TOR pathway. But the role of molecular damage distinguishes cancer and aging. Furthermore, an analysis of the role of both damage and aging in cancer argues against "a decline, caused by accumulation of molecular damage" as a cause of aging. I also discuss how random molecular damage, via rounds of multiplication and selection, brings about non-random hallmarks of cancer.
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Affiliation(s)
- Mikhail V Blagosklonny
- Department of Cell Stress Biology, Roswell Park Cancer Institute, Buffalo, NY 14263, USA.
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427
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Scarpulla RC. Nucleus-encoded regulators of mitochondrial function: integration of respiratory chain expression, nutrient sensing and metabolic stress. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2011; 1819:1088-97. [PMID: 22080153 DOI: 10.1016/j.bbagrm.2011.10.011] [Citation(s) in RCA: 91] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/06/2011] [Accepted: 10/28/2011] [Indexed: 12/23/2022]
Abstract
Nucleus-encoded regulatory factors are major contributors to mitochondrial biogenesis and function. Several act within the organelle to regulate mitochondrial transcription and translation while others direct the expression of nuclear genes encoding the respiratory chain and other oxidative functions. Loss-of-function studies for many of these factors reveal a wide spectrum of phenotypes. These range from embryonic lethality and severe respiratory chain deficiency to relatively mild mitochondrial defects seen only under conditions of physiological stress. The PGC-1 family of regulated coactivators (PGC-1α, PGC-1β and PRC) plays an important integrative role through their interactions with transcription factors (NRF-1, NRF-2, ERRα, CREB, YY1 and others) that control respiratory gene expression. In addition, recent evidence suggests that PGC-1 coactivators may balance the cellular response to oxidant stress by promoting a pro-oxidant environment or by orchestrating an inflammatory response to severe metabolic stress. These pathways may serve as essential links between the energy generating functions of mitochondria and the cellular REDOX environment associated with longevity, senescence and disease. This article is part of a Special Issue entitled: Mitochondrial Gene Expression.
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Affiliation(s)
- Richard C Scarpulla
- Department of Cell and Molecular Biology, Northwestern Medical School, Chicago, IL 60611, USA.
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428
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Azad A, Jackson S, Cullinane C, Natoli A, Neilsen PM, Callen DF, Maira SM, Hackl W, McArthur GA, Solomon B. Inhibition of DNA-dependent protein kinase induces accelerated senescence in irradiated human cancer cells. Mol Cancer Res 2011; 9:1696-707. [PMID: 22009179 DOI: 10.1158/1541-7786.mcr-11-0312] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
DNA-dependent protein kinase (DNA-PK) plays a pivotal role in the repair of DNA double-strand breaks (DSB) and is centrally involved in regulating cellular radiosensitivity. Here, we identify DNA-PK as a key therapeutic target for augmenting accelerated senescence in irradiated human cancer cells. We find that BEZ235, a novel inhibitor of DNA-PK and phosphoinositide 3-kinase (PI3K)/mTOR, abrogates radiation-induced DSB repair resulting in cellular radiosensitization and growth delay of irradiated tumor xenografts. Importantly, radiation enhancement by BEZ235 coincides with a prominent p53-dependent accelerated senescence phenotype characterized by positive β-galactosidase staining, G(2)-M cell-cycle arrest, enlarged and flattened cellular morphology, and increased p21 expression and senescence-associated cytokine secretion. Because this senescence response to BEZ235 is accompanied by unrepaired DNA DSBs, we examined whether selective targeting of DNA-PK also induces accelerated senescence in irradiated cells. Significantly, we show that specific pharmacologic inhibition of DNA-PK, but not PI3K or mTORC1, delays DSB repair leading to accelerated senescence after radiation. We additionally show that PRKDC knockdown using siRNA promotes a striking accelerated senescence phenotype in irradiated cells comparable with that of BEZ235. Thus, in the context of radiation treatment, our data indicate that inhibition of DNA-PK is sufficient for the induction of accelerated senescence. These results validate DNA-PK as an important therapeutic target in irradiated cancer cells and establish accelerated senescence as a novel mechanism of radiosensitization induced by DNA-PK blockade.
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Affiliation(s)
- Arun Azad
- Division of Cancer Research, Peter MacCallum Cancer Centre, East Melbourne, Victoria, Australia
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429
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Serra MP, Doratiotto S, Marongiu F, Laconi E. Normal hepatocyte transplantation delays the emergence of chemically induced preneoplastic nodules in rat liver. Cell Transplant 2011; 21:671-7. [PMID: 21944459 DOI: 10.3727/096368911x600975] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Cancer often arises in a background of chronic tissue damage. It is also increasingly appreciated that such an injured tissue microenvironment might foster the selective emergence of altered cells, leading to neoplasia. Accordingly, reversal of chronic tissue damage could represent a potential strategy to counteract neoplastic disease. In these studies, we aim to investigate whether transplantation of normal cells in the context of an injured, neoplastic-prone microenvironment might impact on the evolution of the carcinogenic process. A rat model of chemically induced hepatocarcinogenesis was used. Animals were given a single dose of diethylnitrosamine (DENA), followed by two injections of retrorsine (RS), a pyrrolizidine alkaloid that imposes a persistent block on hepatocyte cell cycle. At the end of this protocol, rats were either given no further treatment or injected, via the portal circulation, with 4 million normal hepatocytes isolated from a syngenic donor. After 3 months, rats given DENA+RS alone displayed numerous discrete nodular lesions (up to 30 per liver), ranging 1 to 3 mm in size. On the other hand, in animals receiving DENA+RS and transplantation, donor hepatocytes were able to repopulate over 50% of the host liver, as expected. Most importantly, both the number and the size of hepatocyte nodules were greatly reduced in these animals (percent nodular area was 1.8 ± 0.3, down from a control value of 8.5 ± 2.8). The above data indicate that strategies aimed at reestablishing a normal tissue microenvironment might be relevant to the management of neoplastic disease.
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Affiliation(s)
- Maria Paola Serra
- Department of Biomedical Sciences, Unit of Experimental Medicine, University of Cagliari, Cagliari, Italy
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430
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Sabin RJ, Anderson RM. Cellular Senescence - its role in cancer and the response to ionizing radiation. Genome Integr 2011; 2:7. [PMID: 21834983 PMCID: PMC3169443 DOI: 10.1186/2041-9414-2-7] [Citation(s) in RCA: 78] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2011] [Accepted: 08/11/2011] [Indexed: 12/11/2022] Open
Abstract
Cellular senescence is a normal biological process that is initiated in response to a range of intrinsic and extrinsic factors that functions to remove irreparable damage and therefore potentially harmful cells, from the proliferative pool. Senescence can therefore be thought of in beneficial terms as a tumour suppressor. In contrast to this, there is a growing body of evidence suggesting that senescence is also associated with the disruption of the tissue microenvironment and development of a pro-oncogenic environment, principally via the secretion of senescence-associated pro-inflammatory factors. The fraction of cells in a senescent state is known to increase with cellular age and from exposure to various stressors including ionising radiation therefore, the implications of the detrimental effects of the senescent phenotype are important to understand within the context of the increasing human exposure to ionising radiation. This review will discuss what is currently understood about senescence, highlighting possible associations between senescence and cancer and, how exposure to ionising radiation may modify this.
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Affiliation(s)
- Rebecca J Sabin
- Centre for Cell and Chromosome Biology and Centre for Infection, Immunity and Disease Mechanisms, Division of Biosciences, Brunel University, West London, UB8 3PH, UK.
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431
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Maxwell F, McGlynn LM, Muir HC, Talwar D, Benzeval M, Robertson T, Roxburgh CS, McMillan DC, Horgan PG, Shiels PG. Telomere attrition and decreased fetuin-A levels indicate accelerated biological aging and are implicated in the pathogenesis of colorectal cancer. Clin Cancer Res 2011; 17:5573-81. [PMID: 21753158 DOI: 10.1158/1078-0432.ccr-10-3271] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
PURPOSE Increasing chronological age is a risk factor for many types of cancer including colorectal. An understanding of the biology of aging and factors which regulate it may provide insight into cancer pathogenesis. The role of telomere biology in both the cancer and aging process could prove useful in this regard. EXPERIMENTAL DESIGN Using quantitative PCR, we determined telomere length in the peripheral blood leukocytes of 64 colorectal cancer (CRC) patients and 1,348 controls. We also measured telomere length in 32 colorectal tumor samples and matched normal tissue. We aimed to assess whether telomere lengths were reflected in circulating mediators of inflammation and redox control factors, including fetuin-A, a circulating modulator of calcium homeostasis. RESULTS CRC patients had shorter telomeres [adjusted mean ratio of relative telomere repeat copy number to single-copy gene number (RelT/S) = 0.61] compared with chronologically older controls (mean age = 75, adjusted mean RelT/S = 0.70; ANCOVA, P = 0.004). Telomere length in tumor tissue [median = 0.43, interquartile range (IQR) = 0.40] was significantly shorter than adjacent normal tissue (median = 0.65, IQR = 0.28; P = 0.004). Patients with low fetuin-A levels were shown to have significantly shorter telomeres (P = 0.041). Patients with rectal tumors had significantly higher levels of fetuin-A than those with colonic tumors (P = 0.045). CONCLUSIONS We have observed that patients with CRC display clear evidence of telomere attrition compared with controls. This is congruent with accelerated biological aging in the pathogenesis of CRC. An imbalance in redox control mechanisms and calcium homeostasis may be a contributing factor to telomere dynamics in our patients. Furthermore, fetuin-A levels can be used to distinguish between colon and rectal cancers.
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Affiliation(s)
- Fraser Maxwell
- Department of Surgery, Institute of Cancer Sciences, University of Glasgow, Western Infirmary, Scotland, UK
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432
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Witkiewicz AK, Rivadeneira DB, Ertel A, Kline J, Hyslop T, Schwartz GF, Fortina P, Knudsen ES. Association of RB/p16-pathway perturbations with DCIS recurrence: dependence on tumor versus tissue microenvironment. THE AMERICAN JOURNAL OF PATHOLOGY 2011; 179:1171-8. [PMID: 21756866 DOI: 10.1016/j.ajpath.2011.05.043] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/16/2011] [Revised: 05/18/2011] [Accepted: 05/31/2011] [Indexed: 12/27/2022]
Abstract
The prevalence of ductal carcinoma in situ (DCIS) diagnoses has significantly increased as a result of active radiographic screening. Surgical resection and hormone and radiation therapies are effective treatments, but not all DCIS will progress to invasive breast cancer. Therefore, markers are needed to define tumors at low risk of recurrence and progression that can be treated by surgery alone rather than by adjuvant therapies. Initial analyses indicate that retinoblastoma (RB)-pathway perturbations occur at high frequency in DCIS and mirror the molecular alterations observed in invasive breast cancer. Particularly, the elevated expression of p16ink4a in DCIS was associated with loss of RB function and estrogen receptor-negative biology. Furthermore, high expression of p16ink4a in conjunction with Ki-67 was associated with increased risk of DCIS recurrence and progression to invasive disease in multivariate analyses. These data are consistent with a functional role for RB in modulating the invasive behavior of mammary epithelial cells. The tissue microenvironment is particularly relevant to the behavior of DCIS, and, surprisingly, elevated expression of p16ink4a in nonproliferative stroma was observed in a substantial fraction of cases. In this tissue compartment, p16ink4a expression was strongly associated with disease recurrence, independent of standard histopathologic features. Together, the data herein describe dual aspects of RB-pathway biology that are associated with disease recurrence through the epithelial or stromal compartment of DCIS.
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433
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Brody JS, Steiling K. Interaction of cigarette exposure and airway epithelial cell gene expression. Annu Rev Physiol 2011; 73:437-56. [PMID: 21090967 DOI: 10.1146/annurev-physiol-012110-142219] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Cigarette smoking is responsible for lung cancer and chronic obstructive pulmonary disease (COPD), the leading cause of death from cancer and the second-leading cause of death in the United States. In the United States, 46 million people smoke, with an equal number of former smokers. Moreover, 20-25% of current or former smokers will develop either disease, and smokers with one disease are at increased risk for developing the other. There are no tools for predicting risk of developing either disease; no accepted tools for early diagnosis of potentially curable lung cancer; and no tools for defining molecular pathways or molecular subtypes of these diseases, for predicting rate of progression, or for assessing response to therapy at a biochemical or molecular level. This review discusses current studies and the future potential of measuring global gene expression in epithelial cells that are in the airway field of injury and of using the genomic information derived to begin to answer some of the above questions.
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Affiliation(s)
- Jerome S Brody
- Pulmonary Center, Boston University School of Medicine, Massachusetts 02218, USA.
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434
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Pine SR, Mechanic LE, Enewold L, Chaturvedi AK, Katki HA, Zheng YL, Bowman ED, Engels EA, Caporaso NE, Harris CC. Increased levels of circulating interleukin 6, interleukin 8, C-reactive protein, and risk of lung cancer. J Natl Cancer Inst 2011; 103:1112-22. [PMID: 21685357 DOI: 10.1093/jnci/djr216] [Citation(s) in RCA: 244] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
BACKGROUND Previous studies that were based primarily on small numbers of patients suggested that certain circulating proinflammatory cytokines may be associated with lung cancer; however, large independent studies are lacking. METHODS Associations between serum interleukin 6 (IL-6) and interleukin 8 (IL-8) levels and lung cancer were analyzed among 270 case patients and 296 control subjects participating in the National Cancer Institute-Maryland (NCI-MD) case-control study. Results were validated in 532 case patients and 595 control subjects in a nested case-control study within the prospective Prostate, Lung, Colorectal, and Ovarian (PLCO) Cancer Screening Trial. Association with C-reactive protein (CRP), a systemic inflammation biomarker, was also analyzed. Associations between biomarkers and lung cancer were estimated using logistic regression models adjusted for smoking, stage, histology, age, and sex. The 10-year standardized absolute risks of lung cancer were estimated using a weighted Cox regression model. RESULTS Serum IL-6 and IL-8 levels in the highest quartile were associated with lung cancer in the NCI-MD study (IL-6, odds ratio [OR] = 3.29, 95% confidence interval [CI] = 1.88 to 5.77; IL-8, OR = 2.06, 95% CI = 1.19 to 3.57) and with lung cancer risk in the PLCO study (IL-6, OR = 1.48, 95% CI = 1.04 to 2.10; IL-8, OR = 1.57, 95% CI = 1.10 to 2.24), compared with the lowest quartile. In the PLCO study, increased IL-6 levels were only associated with lung cancer diagnosed within 2 years of blood collection, whereas increased IL-8 levels were associated with lung cancer diagnosed more than 2 years after blood collection (OR = 1.57, 95% CI = 1.15 to 2.13). The 10-year standardized absolute risks of lung cancer in the PLCO study were highest among current smokers with high IL-8 and CRP levels (absolute risk = 8.01%, 95% CI = 5.77% to 11.05%). CONCLUSIONS Although increased levels of both serum IL-6 and IL-8 are associated with lung cancer, only IL-8 levels are associated with lung cancer risk several years before diagnosis. Combination of IL-8 and CRP are more robust biomarkers than either marker alone in predicting subsequent lung cancer.
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Affiliation(s)
- Sharon R Pine
- Laboratory of Human Carcinogenesis, Center for Cancer Research, National Cancer Institute, Bethesda, MD 20892-4258, USA
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435
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Schauer IG, Rowley DR. The functional role of reactive stroma in benign prostatic hyperplasia. Differentiation 2011; 82:200-10. [PMID: 21664759 DOI: 10.1016/j.diff.2011.05.007] [Citation(s) in RCA: 91] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2011] [Revised: 05/03/2011] [Accepted: 05/16/2011] [Indexed: 12/19/2022]
Abstract
The human prostate gland is one of the only internal organs that continue to enlarge throughout adulthood. The specific mechanisms that regulate this growth, as well as the pathological changes leading to the phenotype observed in the disease benign prostatic hyperplasia (BPH), are essentially unknown. Recent studies and their associated findings have made clear that many complex alterations occur, involving persistent and chronic inflammation, circulating hormonal level deregulation, and aberrant wound repair processes. BPH has been etiologically characterized as a progressive, albeit discontinuous, hyperplasia of both the glandular epithelial and the stromal cell compartments coordinately yielding an expansion of the prostate gland and clinical symptoms. Interestingly, the inflammatory and repair responses observed in BPH are also key components of general wound repair in post-natal tissues. These responses include altered expression of chemokines, cytokines, matrix remodeling factors, chronic inflammatory processes, altered immune surveillance and recognition, as well as the formation of a prototypical 'reactive' stroma, which is similar to that observed across various fibroplasias and malignancies of a variety of tissue sites. Stromal tissue, both embryonic mesenchyme and adult reactive stroma myofibroblasts, has been shown to exert potent and functional regulatory control over epithelial proliferation and differentiation as well as immunoresponsive modulation. Thus, the functional biology of a reactive stroma, within the context of an adult disease typified by epithelial and stromal aberrant hyperplasia, is critical to understand within the context of prostate disease and beyond. The mechanisms that regulate reactive stroma biology in BPH represent targets of opportunity for new therapeutic approaches that may extend to other tissue contexts. Accordingly, this review seeks to address the dissection of important factors, signaling pathways, genes, and other regulatory components that mediate the interplay between epithelium and stromal responses in BPH.
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Affiliation(s)
- Isaiah G Schauer
- Department of Molecular and Cellular Biology, One Baylor Plaza, Jewish Research Institute, Baylor College of Medicine, 325D, mailstop BCM130, Houston, TX 77030, USA.
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436
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Khatami M. Unresolved inflammation: 'immune tsunami' or erosion of integrity in immune-privileged and immune-responsive tissues and acute and chronic inflammatory diseases or cancer. Expert Opin Biol Ther 2011; 11:1419-32. [PMID: 21663532 DOI: 10.1517/14712598.2011.592826] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
INTRODUCTION Unresolved inflammation is loss of balance between two biologically opposing arms of acute inflammation, 'Yin' (tumoricidal) and 'Yang' (tumorigenic) processes that cause disruption of protective mechanisms of immune system. AREAS COVERED HYPOTHESIS Unresolved inflammation-induced exaggerated expression of apoptotic and/or wound healing mediators lead to fundamental erosion ('immune tsunami' or 'immune meltdown') of integrity in tissues that are naturally immune-responsive (immune surveillance); or immune-privileged (immune tolerance). 'Immune tsunami' refers to end results of acute or chronic immune dysfunction leading to inflammatory diseases or cancer. Acute inflammatory diseases including drug-induced cancer cachexia, would fit features of 'immune meltdown' that are otherwise described for end results of age-associated diseases. Pathogens induce rapid destruction of vascular integrity, gain access to tissues and cause excessive expression of apoptotic factors leading to multiple organ failure (MOF). Significant disruptions of immunological barriers and response shifts lead to chronic neurodegenerative and autoimmune diseases, tumor growth, malignancies and angiogenesis and loss of natural immune response balances. EXPERT OPINION Strategies to promote (stabilize) inherent properties of innate immune cells ('tumoricidal' versus 'tumorigenesis') that would influence polarization of adaptive immune (T or B) cells are key in reducing or preventing incidence of inflammatory and vascular diseases or cancer during aging process.
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Affiliation(s)
- Mahin Khatami
- National Cancer Institute, National Institutes of Health, Bethesda, MD 20817, USA.
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437
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Zhou F, Onizawa S, Nagai A, Aoshiba K. Epithelial cell senescence impairs repair process and exacerbates inflammation after airway injury. Respir Res 2011; 12:78. [PMID: 21663649 PMCID: PMC3118351 DOI: 10.1186/1465-9921-12-78] [Citation(s) in RCA: 73] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2011] [Accepted: 06/10/2011] [Indexed: 12/20/2022] Open
Abstract
Background Genotoxic stress, such as by exposure to bromodeoxyuridine (BrdU) and cigarette smoke, induces premature cell senescence. Recent evidence indicates that cellular senescence of various types of cells is accelerated in COPD patients. However, whether the senescence of airway epithelial cells contributes to the development of airway diseases is unknown. The present study was designed to test the hypothesis that premature senescence of airway epithelial cells (Clara cells) impairs repair processes and exacerbates inflammation after airway injury. Methods C57/BL6J mice were injected with the Clara-cell-specific toxicant naphthalene (NA) on days 0, 7, and 14, and each NA injection was followed by a daily dose of BrdU on each of the following 3 days, during which regenerating cells were allowed to incorporate BrdU into their DNA and to senesce. The p38 MAPK inhibitor SB202190 was injected 30 minutes before each BrdU dose. Mice were sacrificed at different times until day 28 and lungs of mice were obtained to investigate whether Clara cell senescence impairs airway epithelial regeneration and exacerbates airway inflammation. NCI-H441 cells were induced to senesce by exposure to BrdU or the telomerase inhibitor MST-312. Human lung tissue samples were obtained from COPD patients, asymptomatic smokers, and nonsmokers to investigate whether Clara cell senescence is accelerated in the airways of COPD patients, and if so, whether it is accompanied by p38 MAPK activation. Results BrdU did not alter the intensity of the airway epithelial injury or inflammation after a single NA exposure. However, after repeated NA exposure, BrdU induced epithelial cell (Clara cell) senescence, as demonstrated by a DNA damage response, p21 overexpression, increased senescence-associated β-galactosidase activity, and growth arrest, which resulted in impaired epithelial regeneration. The epithelial senescence was accompanied by p38 MAPK-dependent airway inflammation. Senescent NCI-H441 cells impaired epithelial wound repair and secreted increased amounts of pro-inflammatory cytokines in a p38 MAPK-dependent manner. Clara cell senescence in COPD patients was accelerated and accompanied by p38 MAPK activation. Conclusions Senescence of airway epithelial cells impairs repair processes and exacerbates p38 MAPK-dependent inflammation after airway injury, and it may contribute to the pathogenesis of COPD.
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Affiliation(s)
- Fang Zhou
- Graduate School of Medical Science, Tokyo Women's Medical University, Shinjuku-ku, Tokyo, Japan
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438
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Salminen A, Ojala J, Kaarniranta K, Haapasalo A, Hiltunen M, Soininen H. Astrocytes in the aging brain express characteristics of senescence-associated secretory phenotype. Eur J Neurosci 2011; 34:3-11. [PMID: 21649759 DOI: 10.1111/j.1460-9568.2011.07738.x] [Citation(s) in RCA: 235] [Impact Index Per Article: 18.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Cellular stress increases progressively with aging in mammalian tissues. Chronic stress triggers several signaling cascades that can induce a condition called cellular senescence. Recent studies have demonstrated that senescent cells express a senescence-associated secretory phenotype (SASP). Emerging evidence indicates that the number of cells expressing biomarkers of cellular senescence increases in tissues with aging, which implies that cellular senescence is an important player in organismal aging. In the brain, the aging process is associated with degenerative changes, e.g. synaptic loss and white matter atrophy, which lead to progressive cognitive impairment. There is substantial evidence for the presence of oxidative, proteotoxic and metabolic stresses in aging brain. A low-level, chronic inflammatory process is also present in brain during aging. Astrocytes demonstrate age-related changes that resemble those of the SASP: (i) increased level of intermediate glial fibrillary acidic protein and vimentin filaments, (ii) increased expression of several cytokines and (iii) increased accumulation of proteotoxic aggregates. In addition, in vitro stress evokes a typical senescent phenotype in cultured astrocytes and, moreover, isolated astrocytes from aged brain display the proinflammatory phenotype. All of these observations indicate that astrocytes are capable of triggering the SASP and the astrocytes in aging brain display typical characteristics of cellular senescence. Bearing in mind the many functions of astrocytes, it is evident that the age-related senescence of astrocytes enhances the decline in functional capacity of the brain. We will review the astroglial changes occurring during aging and emphasize that senescent astrocytes can have an important role in age-related neuroinflammation and neuronal degeneration.
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Affiliation(s)
- Antero Salminen
- Department of Neurology, Institute of Clinical Medicine, University of Eastern Finland, Kuopio, Finland.
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439
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Dhahbi JM, Atamna H, Boffelli D, Magis W, Spindler SR, Martin DIK. Deep sequencing reveals novel microRNAs and regulation of microRNA expression during cell senescence. PLoS One 2011; 6:e20509. [PMID: 21637828 PMCID: PMC3102725 DOI: 10.1371/journal.pone.0020509] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2011] [Accepted: 04/29/2011] [Indexed: 11/19/2022] Open
Abstract
In cell senescence, cultured cells cease proliferating and acquire aberrant gene expression patterns. MicroRNAs (miRNAs) modulate gene expression through translational repression or mRNA degradation and have been implicated in senescence. We used deep sequencing to carry out a comprehensive survey of miRNA expression and involvement in cell senescence. Informatic analysis of small RNA sequence datasets from young and senescent IMR90 human fibroblasts identifies many miRNAs that are regulated (either up or down) with cell senescence. Comparison with mRNA expression profiles reveals potential mRNA targets of these senescence-regulated miRNAs. The target mRNAs are enriched for genes involved in biological processes associated with cell senescence. This result greatly extends existing information on the role of miRNAs in cell senescence and is consistent with miRNAs having a causal role in the process.
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Affiliation(s)
- Joseph M. Dhahbi
- Center for Genetics, Children's Hospital Oakland Research Institute, Oakland, California, United States of America
- Department of Biochemistry, University of California Riverside, Riverside, California, United States of America
- * E-mail: (JMD); (HA); (DIKM)
| | - Hani Atamna
- Department of Basic Sciences, Neuroscience, The Commonwealth Medical College, Scranton, Pennsylvania, United States of America
- * E-mail: (JMD); (HA); (DIKM)
| | - Dario Boffelli
- Center for Genetics, Children's Hospital Oakland Research Institute, Oakland, California, United States of America
| | - Wendy Magis
- Center for Genetics, Children's Hospital Oakland Research Institute, Oakland, California, United States of America
| | - Stephen R. Spindler
- Department of Biochemistry, University of California Riverside, Riverside, California, United States of America
| | - David I. K. Martin
- Center for Genetics, Children's Hospital Oakland Research Institute, Oakland, California, United States of America
- * E-mail: (JMD); (HA); (DIKM)
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440
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Cho JH, Saini DK, Karunarathne WA, Kalyanaraman V, Gautam N. Alteration of Golgi structure in senescent cells and its regulation by a G protein γ subunit. Cell Signal 2011; 23:785-93. [PMID: 21238584 PMCID: PMC3085901 DOI: 10.1016/j.cellsig.2011.01.001] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2010] [Revised: 12/21/2010] [Accepted: 01/05/2011] [Indexed: 11/20/2022]
Abstract
Cellular senescence is a process wherein proliferating cells undergo permanent cell cycle arrest while remaining viable. Senescence results in enhanced secretion of proteins that promote cancer and inflammation. We report here that the structure of the Golgi complex which regulates secretion is altered in senescent cells. In cells where senescence is achieved by replicative exhaustion or in cells wherein senescence has been induced with BrdU treatment dependent stress, the Golgi complex is dispersed. The expression of a G protein γ subunit, γ11, capable of translocation from the plasma membrane to the Golgi complex on receptor activation increases with senescence. Knockdown of γ11 or overexpression of a dominant negative γ3 subunit inhibits Golgi dispersal induced by senescence. Overall these results suggest that in cellular senescence an upregulated G protein gamma subunit mediates alterations in the structure of the Golgi.
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Affiliation(s)
- Joon-Ho Cho
- Department of Anesthesiology, Washington University School of Medicine, St. Louis, MO 63110
| | - Deepak Kumar Saini
- Department of Anesthesiology, Washington University School of Medicine, St. Louis, MO 63110
| | | | - Vani Kalyanaraman
- Department of Anesthesiology, Washington University School of Medicine, St. Louis, MO 63110
| | - N. Gautam
- Department of Anesthesiology, Washington University School of Medicine, St. Louis, MO 63110
- Department of Genetics, Washington University School of Medicine, St. Louis, MO 63110
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441
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Abstract
The PinX1 protein inhibits telomerase, an enzyme that lengthens telomeres - the structures that protect the ends of chromosomes. Loss of PinX1 leads to increased telomere length along with defects in chromosome dynamics. In this issue of the JCI, Zhou et al. present novel evidence from human tumors and mouse models indicating that PinX1 is a clinically significant tumor suppressor. Importantly, the genome-destabilizing effects of PinX1 loss appear to depend on telomerase activity, raising new models and questions for how telomeres and telomerase contribute to the development of cancer.
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Affiliation(s)
- F Brad Johnson
- Department of Pathology and Laboratory Medicine, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania, USA.
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442
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p38MAPK is a novel DNA damage response-independent regulator of the senescence-associated secretory phenotype. EMBO J 2011; 30:1536-48. [PMID: 21399611 PMCID: PMC3102277 DOI: 10.1038/emboj.2011.69] [Citation(s) in RCA: 681] [Impact Index Per Article: 52.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2010] [Accepted: 02/18/2011] [Indexed: 12/11/2022] Open
Abstract
Cellular senescence suppresses cancer by forcing potentially oncogenic cells into a permanent cell cycle arrest. Senescent cells also secrete growth factors, proteases, and inflammatory cytokines, termed the senescence-associated secretory phenotype (SASP). Much is known about pathways that regulate the senescence growth arrest, but far less is known about pathways that regulate the SASP. We previously showed that DNA damage response (DDR) signalling is essential, but not sufficient, for the SASP, which is restrained by p53. Here, we delineate another crucial SASP regulatory pathway and its relationship to the DDR and p53. We show that diverse senescence-inducing stimuli activate the stress-inducible kinase p38MAPK in normal human fibroblasts. p38MAPK inhibition markedly reduced the secretion of most SASP factors, constitutive p38MAPK activation was sufficient to induce an SASP, and p53 restrained p38MAPK activation. Further, p38MAPK regulated the SASP independently of the canonical DDR. Mechanistically, p38MAPK induced the SASP largely by increasing NF-κB transcriptional activity. These findings assign p38MAPK a novel role in SASP regulation--one that is necessary, sufficient, and independent of previously described pathways.
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443
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Couillard J, Estève PO, Pradhan S, St-Pierre Y. 5-Aza-2′-deoxycytidine and interleukin-1 cooperate to regulate matrix metalloproteinase-3 gene expression. Int J Cancer 2011; 129:2083-92. [DOI: 10.1002/ijc.25865] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2010] [Accepted: 11/30/2010] [Indexed: 12/31/2022]
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444
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Impact of cellular senescence signature on ageing research. Ageing Res Rev 2011; 10:146-52. [PMID: 20946972 DOI: 10.1016/j.arr.2010.10.002] [Citation(s) in RCA: 192] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2010] [Revised: 10/01/2010] [Accepted: 10/01/2010] [Indexed: 01/08/2023]
Abstract
Cellular senescence as the state of permanent inhibition of cell proliferation is a tumour-suppressive mechanism. However, due to the associated secretory phenotype senescence can also contribute to cancer and possibly other age-related diseases, such as obesity, diabetes, atherosclerosis and Alzheimer's disease. There are two major mechanisms of cellular senescence; replicative senescence depends on telomere erosion or dysfunction whilst stress-induced premature senescence (SIPS) is telomere-independent and also includes oncogene-induced senescence (OIS). The senescence phenotype is characterised by altered cellular morphology, increased activity for senescence-associated-β-galactosidase (SA-β-GAL), increased formation of senescence-associated heterochromatin foci (SAHF) and promyelocytic leukemia protein nuclear bodies (PML NBs), permanent DNA damage, chromosomal instability and an inflammatory secretome. Some of these markers have been identified in cells from age-related pathologies. However, to improve our understanding of the contribution of cellular senescence to organismal ageing and age-related disease, it is imperative to define an unequivocal signature of cellular senescence that is functionally connected with normal and pathological ageing. Herein, we describe the processes leading to senescence, and the current biomarkers of cellular senescence, with particular emphasis on the causal role of DNA damage responses involved in the process. We highlight the gaps in our knowledge both of the processes leading to senescence, and the signature of cellular senescence both in vitro and in vivo. A well-defined set of senescence biomarkers for ageing and age-related disease would have a strong impact on the diagnosis, staging and predicted outcomes of age-related disease, providing the basis for a pharmacological intervention to postpone ageing and age-related disease.
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445
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Vergel M, Marin JJ, Estevez P, Carnero A. Cellular senescence as a target in cancer control. J Aging Res 2010; 2011:725365. [PMID: 21234095 PMCID: PMC3018654 DOI: 10.4061/2011/725365] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2010] [Accepted: 11/03/2010] [Indexed: 01/04/2023] Open
Abstract
Somatic cells show a spontaneous decline in growth rate in continuous culture. This is not related to elapsed time but to an increasing number of population doublings, eventually terminating in a quiescent but viable state termed replicative senescence. These cells are commonly multinucleated and do not respond to mitogens or apoptotic stimuli. Cells displaying characteristics of senescent cells can also be observed in response to other stimuli, such as oncogenic stress, DNA damage, or cytotoxic drugs and have been reported to be found in vivo. Most tumors show unlimited replicative potential, leading to the hypothesis that cellular senescence is a natural antitumor program. Recent findings suggest that cellular senescence is a natural mechanism to prevent undesired oncogenic stress in somatic cells that has been lost in malignant tumors. Given that the ultimate goal of cancer research is to find the definitive cure for as many tumor types as possible, exploration of cellular senescence to drive towards antitumor therapies may decisively influence the outcome of new drugs. In the present paper, we will review the potential of cellular senescence to be used as target for anticancer therapy.
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Affiliation(s)
- Mar Vergel
- Instituto de Biomedicina de Sevilla, Hospital Universitario virgen del Rocio, 41013 Sevilla, Spain
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446
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447
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Balducci L. Anemia, fatigue and aging. Transfus Clin Biol 2010; 17:375-81. [PMID: 21067951 DOI: 10.1016/j.tracli.2010.09.169] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2010] [Accepted: 09/19/2010] [Indexed: 10/18/2022]
Abstract
Aging is associated with increased incidence and prevalence of both cancer and anemia. Cancer and aging may conspire in making anemia more frequent and more severe. This article reviews the causes and the consequences of anemia in the older individual. The most common causes include chronic inflammation that is a typical manifestation of aging, iron deficiency that may be due to chronic hemorrhage, malabsorption and Helicobacter pylori infection, cobalamin deficiency from malabsorption and renal insufficiency. Other causes of anemia whose prevalence is not well established include myelodysplasia, copper deficiency, hypothyroidism, and sarcopenia. Anemia is associated with increased risk of mortality, functional dependence, dementia, falls, and chemotherapy-related toxicity. When correcting the anemia of older cancer patients one should remember that the erythropoietic stimulating agents (ESA) may stimulate cancer growth and cause thrombosis. These products may be safe when given exclusively to patients receiving chemotherapy and when the hemoglobin levels are maintained below 12 g/dL.
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Affiliation(s)
- L Balducci
- H Lee Moffitt Cancer Center & Research Institute, 12902 Magnolia Dr, Tampa, FL 33612, USA.
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448
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Chen LH, Chiou GY, Chen YW, Li HY, Chiou SH. MicroRNA and aging: a novel modulator in regulating the aging network. Ageing Res Rev 2010; 9 Suppl 1:S59-66. [PMID: 20708718 DOI: 10.1016/j.arr.2010.08.002] [Citation(s) in RCA: 77] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2010] [Accepted: 07/29/2010] [Indexed: 10/19/2022]
Abstract
miRNAs are a group of noncoding small RNA that are capable of modulating the expression of hundreds of genes via a near-perfect or partial complementary to target mRNA. The ability to regulate multiple targets simultaneously makes miRNA a crucial regulator in many physiological conditions, especially in the aging network and process. The tremendous capability of miRNA supports its ability in regulating ageing, which is a complex process involving multiple interconnected signaling pathways. Even though the relationship between miRNA and ageing is not fully understood, studies have provided evidence showing that miRNAs participate in regulating cell cycle progression, proliferation, stemness gene expression, and stress-induced responses. Molecular studies of ageing and miRNAs would provide a more comprehensive understanding of the mechanisms of ageing and, subsequently, help to ameliorate this universal process compromising our quality of life. In this review article, we focus our attention on miRNA targets in conserved pathways involved in organism aging and aging networks, as well as cellular senescence.
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449
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Long-distance inflammatory and genotoxic impact of cancer in vivo. Proc Natl Acad Sci U S A 2010; 107:17861-2. [PMID: 20926747 DOI: 10.1073/pnas.1013093107] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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