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Du XY, Yang JY. Biomimetic microfluidic chips for toxicity assessment of environmental pollutants. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 919:170745. [PMID: 38340832 DOI: 10.1016/j.scitotenv.2024.170745] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2023] [Revised: 01/31/2024] [Accepted: 02/04/2024] [Indexed: 02/12/2024]
Abstract
Various types of pollutants widely present in environmental media, including synthetic and natural chemicals, physical pollutants such as radioactive substances, ultraviolet rays, and noise, as well as biological organisms, pose a huge threat to public health. Therefore, it is crucial to accurately and effectively explore the human physiological responses and toxicity mechanisms of pollutants to prevent diseases caused by pollutants. The emerging toxicological testing method biomimetic microfluidic chips (BMCs) exhibit great potential in environmental pollutant toxicity assessment due to their superior biomimetic properties. The BMCs are divided into cell-on-chips and organ-on-chips based on the distinctions in bionic simulation levels. Herein, we first summarize the characteristics, emergence and development history, composition and structure, and application fields of BMCs. Then, with a focus on the toxicity mechanisms of pollutants, we review the applications and advances of the BMCs in the toxicity assessment of physical, chemical, and biological pollutants, respectively, highlighting its potential and development prospects in environmental toxicology testing. Finally, the opportunities and challenges for further use of BMCs are discussed.
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Affiliation(s)
- Xin-Yue Du
- College of Architecture and Environment, Sichuan University, Chengdu 610065, China
| | - Jin-Yan Yang
- College of Architecture and Environment, Sichuan University, Chengdu 610065, China..
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2
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Dave JR, Chandekar SS, Behera S, Desai KU, Salve PM, Sapkal NB, Mhaske ST, Dewle AM, Pokare PS, Page M, Jog A, Chivte PA, Srivastava RK, Tomar GB. Human gingival mesenchymal stem cells retain their growth and immunomodulatory characteristics independent of donor age. SCIENCE ADVANCES 2022; 8:eabm6504. [PMID: 35749495 PMCID: PMC9232118 DOI: 10.1126/sciadv.abm6504] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/01/2021] [Accepted: 05/06/2022] [Indexed: 05/28/2023]
Abstract
Aging has been reported to deteriorate the quantity and quality of mesenchymal stem cells (MSCs), which affect their therapeutic use in regenerative medicine. A dearth of age-related stem cell research further restricts their clinical applications. The present study explores the possibility of using MSCs derived from human gingival tissues (GMSCs) for studying their ex vivo growth characteristics and differentiation potential with respect to donor age. GMSCs displayed decreased in vitro adipogenesis and in vitro and in vivo osteogenesis with age, but in vitro neurogenesis remained unaffected. An increased expression of p53 and SIRT1 with donor age was correlated to their ability of eliminating tumorigenic events through apoptosis or autophagy, respectively. Irrespective of donor age, GMSCs displayed effective immunoregulation and regenerative potential in a mouse model of LPS-induced acute lung injury. Thus, we suggest the potential of GMSCs for designing cell-based immunomodulatory therapeutic approaches and their further extrapolation for acute inflammatory conditions such as acute respiratory distress syndrome and COVID-19.
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Affiliation(s)
- Jay R. Dave
- Institute of Bioinformatics and Biotechnology, Savitribai Phule Pune University, Pune, 411007 Maharashtra, India
| | - Sayali S. Chandekar
- Institute of Bioinformatics and Biotechnology, Savitribai Phule Pune University, Pune, 411007 Maharashtra, India
| | - Shubhanath Behera
- National Centre for Cell Science, Savitribai Phule Pune University Campus, Pune, 411007 Maharashtra, India
| | - Kaushik U. Desai
- Institute of Bioinformatics and Biotechnology, Savitribai Phule Pune University, Pune, 411007 Maharashtra, India
| | - Pradnya M. Salve
- Institute of Bioinformatics and Biotechnology, Savitribai Phule Pune University, Pune, 411007 Maharashtra, India
| | - Neha B. Sapkal
- Institute of Bioinformatics and Biotechnology, Savitribai Phule Pune University, Pune, 411007 Maharashtra, India
| | - Suhas T. Mhaske
- Institute of Bioinformatics and Biotechnology, Savitribai Phule Pune University, Pune, 411007 Maharashtra, India
| | - Ankush M. Dewle
- Institute of Bioinformatics and Biotechnology, Savitribai Phule Pune University, Pune, 411007 Maharashtra, India
| | - Parag S. Pokare
- Institute of Bioinformatics and Biotechnology, Savitribai Phule Pune University, Pune, 411007 Maharashtra, India
| | - Megha Page
- Department of Dentistry, Deenanath Mangeshkar Hospital and Research Centre, Pune, 411004 Maharashtra, India
| | - Ajay Jog
- Department of Dentistry, Deenanath Mangeshkar Hospital and Research Centre, Pune, 411004 Maharashtra, India
| | - Pankaj A. Chivte
- Saraswati Danwantri Dental College and Hospital, Parbhani, 431401 Maharashtra, India
| | - Rupesh K. Srivastava
- Department of Biotechnology, All India Institute of Medical Science, New Delhi 110029, India
| | - Geetanjali B. Tomar
- Institute of Bioinformatics and Biotechnology, Savitribai Phule Pune University, Pune, 411007 Maharashtra, India
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Guided Tissue Regeneration in Surgical Endodontic Treatment: Case Report and Literature Review. BALKAN JOURNAL OF DENTAL MEDICINE 2019. [DOI: 10.2478/bjdm-2019-0019] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Summary
Background/Aim: Guided tissue regeneration is widely used in endodontic surgery. The aim is to aid in the healing process and bone regeneration and provide more successful and predictable outcomes.
Case report: This case report describes the successful treatment of an endodontic-periodontal lesion (with primary endodontic involvement), including root canal retreatment and endodontic surgery with the use of GTR (collagen absorbable membrane-xenogeneic bone graft). CBCT examination was used to aid in diagnosis and in the follow-up examination after two years to provide additional confirmation of the healing process. An extensive literature review was undertaken focusing on clinical studies that assessing the added benefit of GTR in surgical endodontics. The clinical and radiographic examinations showed uneventful healing and the reconstruction of the buccal plate and periapical area. The patient remained asymptomatic throughout the entire two years period after surgical intervention. A literature review concluded that lesion type, lesion size and the selection of the biomaterial are important factors that influence the outcome of GTR in comparison control groups. A favorable outcome was found in cases of large periapical lesions (>10mm), through-through lesions and with the use of an absorbable membrane, with or without a bone graft.
Conclusions: GTR is thought to provide an added benefit in bone regeneration and the healing process in specific cases. The outcomes in the case report are consistent with the conclusions of literature review.
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Shetzer Y, Molchadsky A, Rotter V. Oncogenic Mutant p53 Gain of Function Nourishes the Vicious Cycle of Tumor Development and Cancer Stem-Cell Formation. Cold Spring Harb Perspect Med 2016; 6:cshperspect.a026203. [PMID: 27235476 DOI: 10.1101/cshperspect.a026203] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
More than half of human tumors harbor an inactivated p53 tumor-suppressor gene. It is well accepted that mutant p53 shows an oncogenic gain-of-function (GOF) activity that facilitates the transformed phenotype of cancer cells. In addition, a growing body of evidence supports the notion that cancer stem cells comprise a seminal constituent in the initiation and progression of cancer development. Here, we elaborate on the mutant p53 oncogenic GOF leading toward the acquisition of a transformed phenotype, as well as placing mutant p53 as a major component in the establishment of cancer stem cell entity. Therefore, therapy targeted toward cancer stem cells harboring mutant p53 is expected to pave the way to eradicate tumor growth and recurrence.
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Affiliation(s)
- Yoav Shetzer
- Department of Molecular Cell Biology, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Alina Molchadsky
- Department of Molecular Cell Biology, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Varda Rotter
- Department of Molecular Cell Biology, Weizmann Institute of Science, Rehovot 76100, Israel
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5
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Therapeutic role of bone marrow-derived mesenchymal stem cells in cyclophosphamide-induced cardiotoxicity in adult male albino rat. ACTA ACUST UNITED AC 2016. [DOI: 10.1097/01.ehx.0000508456.99217.6e] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Cheng H, Zou T, Xu Y, Wang Y, Wu A, Dai J, Zhang Y, Liu Y. Investigations on the interactions between naphthalimide-based anti-tumor drugs and human serum albumin by spectroscopic and molecular modeling methods. LUMINESCENCE 2015; 31:88-95. [PMID: 25991384 DOI: 10.1002/bio.2928] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2015] [Revised: 03/17/2015] [Accepted: 04/03/2015] [Indexed: 11/06/2022]
Abstract
The interactions between the three kinds of naphthalimide-based anti-tumor drugs (NADA, NADB, NADC) and human serum albumin (HSA) under simulated physiological conditions were investigated by fluorescence spectroscopy, circular dichroism spectroscopy and molecular modeling. The results of the fluorescence quenching spectroscopy showed that the quenching mechanisms for different drugs were static and their affinity was in a descending order of NADA > NADB > NADC. The relative thermodynamic parameters indicated that hydrophobic force was the predominant intermolecular force in the binding of NAD to HSA, while van der Waals interactions and hydrogen bonds could not be ignored. The results of site marker competitive experiment confirmed that the binding site of HSA primarily took place in site I. Furthermore, the molecular modeling study was consistent with these results. The study of circular dichroism spectra demonstrated that the presence of NADs decreased the α-helical content of HSA and induced the change of the secondary structure of HSA.
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Affiliation(s)
- Huiyuan Cheng
- Department of Chemistry, College of Chemistry and Environmental Engineering, Yangtze University, Jingzhou, Hubei, 434023, People's Republic of China
| | - Ting Zou
- Department of Chemistry, College of Chemistry and Environmental Engineering, Yangtze University, Jingzhou, Hubei, 434023, People's Republic of China
| | - Yongliang Xu
- Department of Chemistry, College of Chemistry and Environmental Engineering, Yangtze University, Jingzhou, Hubei, 434023, People's Republic of China
| | - Ying Wang
- Department of Chemistry, College of Chemistry and Environmental Engineering, Yangtze University, Jingzhou, Hubei, 434023, People's Republic of China
| | - Aibin Wu
- Department of Chemistry, College of Chemistry and Environmental Engineering, Yangtze University, Jingzhou, Hubei, 434023, People's Republic of China
| | - Jie Dai
- Department of Chemistry, College of Chemistry and Environmental Engineering, Yangtze University, Jingzhou, Hubei, 434023, People's Republic of China
| | - Yezhong Zhang
- Department of Chemistry, College of Chemistry and Environmental Engineering, Yangtze University, Jingzhou, Hubei, 434023, People's Republic of China
| | - Yi Liu
- College of Chemistry and Molecular Sciences and State Key Laboratory of Virology, Wuhan University, Wuhan, 430072, People's Republic of China
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Li Z, Guo Y, Han L, Zhang Y, Shi L, Huang X, Lin X. Debra-mediated Ci degradation controls tissue homeostasis in Drosophila adult midgut. Stem Cell Reports 2014; 2:135-44. [PMID: 24527387 PMCID: PMC3923220 DOI: 10.1016/j.stemcr.2013.12.011] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2013] [Revised: 12/18/2013] [Accepted: 12/19/2013] [Indexed: 12/21/2022] Open
Abstract
Adult tissue homeostasis is maintained by resident stem cells and their progeny. However, the underlying mechanisms that control tissue homeostasis are not fully understood. Here, we demonstrate that Debra-mediated Ci degradation is important for intestinal stem cell (ISC) proliferation in Drosophila adult midgut. Debra inhibition leads to increased ISC activity and tissue homeostasis loss, phenocopying defects observed in aging flies. These defects can be suppressed by depleting Ci, suggesting that increased Hedgehog (Hh) signaling contributes to ISC proliferation and tissue homeostasis loss. Consistently, Hh signaling activation causes the same defects, whereas depletion of Hh signaling suppresses these defects. Furthermore, the Hh ligand from multiple sources is involved in ISC proliferation and tissue homeostasis. Finally, we show that the JNK pathway acts downstream of Hh signaling to regulate ISC proliferation. Together, our results provide insights into the mechanisms of stem cell proliferation and tissue homeostasis control.
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Affiliation(s)
- Zhouhua Li
- State Key Laboratory of Biomembrane and Membrane Biotechnology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China
| | - Yueqin Guo
- State Key Laboratory of Biomembrane and Membrane Biotechnology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China
| | - Lili Han
- State Key Laboratory of Biomembrane and Membrane Biotechnology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China
| | - Yan Zhang
- State Key Laboratory of Biomembrane and Membrane Biotechnology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China
| | - Lai Shi
- State Key Laboratory of Biomembrane and Membrane Biotechnology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China
| | - Xudong Huang
- School of Optometry and Ophthalmology and Eye Hospital, Wenzhou Medical University, Wenzhou 325000, China
| | - Xinhua Lin
- State Key Laboratory of Biomembrane and Membrane Biotechnology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China ; Division of Developmental Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, USA
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8
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Bartesaghi S, Salomoni P. Tumor suppressive pathways in the control of neurogenesis. Cell Mol Life Sci 2013; 70:581-97. [PMID: 22802124 PMCID: PMC11113109 DOI: 10.1007/s00018-012-1063-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2012] [Revised: 06/16/2012] [Accepted: 06/18/2012] [Indexed: 12/16/2022]
Abstract
The generation of specialized neural cells in the developing and postnatal central nervous system is a highly regulated process, whereby neural stem cells divide to generate committed neuronal progenitors, which then withdraw from the cell cycle and start to differentiate. Cell cycle checkpoints play a major role in regulating the balance between neural stem cell expansion and differentiation. Loss of tumor suppressors involved in checkpoint control can lead to dramatic alterations of neurogenesis, thus contributing to neoplastic transformation. Here we summarize and critically discuss the existing literature on the role of tumor suppressive pathways and their regulatory networks in the control of neurogenesis and transformation.
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Affiliation(s)
- Stefano Bartesaghi
- Samantha Dickson Brain Cancer Unit, UCL Cancer Institute, 72 Huntley Street, London, WC1E 6DD UK
| | - Paolo Salomoni
- Samantha Dickson Brain Cancer Unit, UCL Cancer Institute, 72 Huntley Street, London, WC1E 6DD UK
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9
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Maintenance of genomic stability in mouse embryonic stem cells: relevance in aging and disease. Int J Mol Sci 2013; 14:2617-36. [PMID: 23358251 PMCID: PMC3588006 DOI: 10.3390/ijms14022617] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2012] [Revised: 01/11/2013] [Accepted: 01/12/2013] [Indexed: 01/15/2023] Open
Abstract
Recent studies have shown that mouse embryonic stem cells (mESCs) rely on a distinctive genome caretaking network. In this review, we will discuss how mESCs functionally respond to DNA damage and describe several modifications in mESC DNA damage response, which accommodate dynamic cycling and preservation of genetic information. Subsequently, we will discuss how the transition from mESCs to adult stem/progenitor cells can be involved in the decline of tissue integrity and function in the elderly.
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10
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Targeting lysophosphatidic acid signaling retards culture-associated senescence of human marrow stromal cells. PLoS One 2012; 7:e32185. [PMID: 22359668 PMCID: PMC3281120 DOI: 10.1371/journal.pone.0032185] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2011] [Accepted: 01/23/2012] [Indexed: 01/01/2023] Open
Abstract
Marrow stromal cells (MSCs) isolated from mesenchymal tissues can propagate in vitro to some extent and differentiate into various tissue lineages to be used for cell-based therapies. Cellular senescence, which occurs readily in continual MSC culture, leads to loss of these characteristic properties, representing one of the major limitations to achieving the potential of MSCs. In this study, we investigated the effect of lysophosphatidic acid (LPA), a ubiquitous metabolite in membrane phospholipid synthesis, on the senescence program of human MSCs. We show that MSCs preferentially express the LPA receptor subtype 1, and an abrogation of the receptor engagement with the antagonistic compound Ki16425 attenuates senescence induction in continually propagated human MSCs. This anti-aging effect of Ki16425 results in extended rounds of cellular proliferation, increased clonogenic potential, and retained plasticity for osteogenic and adipogenic differentiation. Expressions of p16(Ink4a), Rb, p53, and p21(Cip1), which have been associated with cellular senescence, were all reduced in human MSCs by the pharmacological inhibition of LPA signaling. Disruption of this signaling pathway was accompanied by morphological changes such as cell thinning and elongation as well as actin filament deformation through decreased phosphorylation of focal adhesion kinase. Prevention of LPA receptor engagement also promoted ubiquitination-mediated c-Myc elimination in MSCs, and consequently the entry into a quiescent state, G(0) phase, of the cell cycle. Collectively, these results highlight the potential of pharmacological intervention against LPA signaling for blunting senescence-associated loss of function characteristic of human MSCs.
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Stefanova VT, Grifo JA, Hansis C. Derivation of novel genetically diverse human embryonic stem cell lines. Stem Cells Dev 2012; 21:1559-70. [PMID: 22204497 DOI: 10.1089/scd.2011.0642] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Human embryonic stem cells (hESCs) have the potential to revolutionize many biomedical fields ranging from basic research to disease modeling, regenerative medicine, drug discovery, and toxicity testing. A multitude of hESC lines have been derived worldwide since the first 5 lines by Thomson et al. 13 years ago, but many of these are poorly characterized, unavailable, or do not represent desired traits, thus making them unsuitable for application purposes. In order to provide the scientific community with better options, we have derived 12 new hESC lines at New York University from discarded genetically normal and abnormal embryos using the latest techniques. We examined the genetic status of the NYUES lines in detail as well as their molecular and cellular features and DNA fingerprinting profile. Furthermore, we differentiated our hESCs into the tissues most affected by a specific condition or into clinically desired cell types. To our knowledge, a number of characteristics of our hESCs have not been previously reported, for example, mutation for alpha thalassemia X-linked mental retardation syndrome, linkage to conditions with a genetic component such as asthma or poor sperm morphology, and novel combinations of ethnic backgrounds. Importantly, all of our undifferentiated euploid female lines tested to date did not show X chromosome inactivation, believed to result in superior potency. We continue to derive new hESC lines and add them to the NIH registry and other registries. This should facilitate the use of our hESCs and lead to advancements for patient-benefitting applications.
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Affiliation(s)
- Valentina T Stefanova
- Department of Obstetrics and Gynecology, New York University School of Medicine, New York, New York, USA
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12
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Dekker P, van Baalen LM, Dirks RW, Slagboom PE, van Heemst D, Tanke HJ, Westendorp RGJ, Maier AB. Chronic inhibition of the respiratory chain in human fibroblast cultures: differential responses related to subject chronological and biological age. J Gerontol A Biol Sci Med Sci 2011; 67:456-64. [PMID: 22080500 DOI: 10.1093/gerona/glr196] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Respiratory chain function becomes less efficient with age resulting in increased levels of damaging reactive oxygen species. We compared rotenone-exposed fibroblast strains from young and old subjects and from offspring of nonagenarian siblings and the partners of the offspring. Rotenone increased reactive oxygen species levels, inhibited growth rate, and increased telomere shortening (all p < .05). Non-stressed strains from young subjects showed lower reactive oxygen species levels (p = .031) and higher growth rates (p = .002) than strains from old subjects. Stressed strains from young subjects showed smaller increases in reactive oxygen species levels (p = .014) and larger decreases in growth rate (p < .001) than strains from old subjects. Telomere-shortening rates were not different between groups. Stress-induced decreases in growth rate were larger in strains from offspring than from partners (p = .05). Strains from young and old subjects are differentially affected by chronic inhibition of the respiratory chain. Changed growth rates in strains from offspring resemble those from strains from young subjects.
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Affiliation(s)
- Pim Dekker
- Department of Gerontology and Geriatrics, Leiden University Medical Center, Leiden, the Netherlands
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Wu A, Mei P, Xu Y, Qian X. Novel Naphthalimide-Benzoic Acid Conjugates as Potential Apoptosis-Inducing Agents: Design, Synthesis, and Biological Activity. Chem Biol Drug Des 2011; 78:941-7. [DOI: 10.1111/j.1747-0285.2011.01232.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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Abstract
AbstractThe young human brain is highly plastic and thus early brain lesions can lead to aberrant development of connectivity and mapping of functions. This is why initially in cerebral palsy only subtle changes in spontaneous movements are seen after the time of lesion, followed by a progressive evolution of a movement disorder over many months and years. Thus we propose that interventions to treat cerebral palsy should be initiated as soon as possible in order to restore the nervous system to the correct developmental trajectory. One such treatment might be autologous stem cell transplantation either intracerebrally or intravenously. All babies come with an accessible supply of stem cells, the umbilical cord, which can supply cells that could theoretically replace missing neural cell types, or act indirectly by supplying trophic support or modulating inflammatory responses to hypoxia/ischaemia. However, for such radical treatment to be proposed, it is necessary to be able to detect and accurately predict the outcomes of brain injury from a very early age. This article reviews our current understanding of perinatal injuries that lead to cerebral palsy, how well modern imaging might predict outcomes, what stem cells are yielded from umbilical cord blood and experimental models of brain repair using stem cells.
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Lui JC, Chen W, Barnes KM, Baron J. Changes in gene expression associated with aging commonly originate during juvenile growth. Mech Ageing Dev 2010; 131:641-9. [PMID: 20816690 DOI: 10.1016/j.mad.2010.08.010] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2010] [Revised: 07/22/2010] [Accepted: 08/25/2010] [Indexed: 01/06/2023]
Abstract
In mammals, proliferation is rapid in many tissues during early postnatal life, causing rapid somatic growth. This robust proliferation is then suppressed as the animal approaches adult size, bringing many tissues to a quiescent state where proliferation occurs only as needed to replace dying cells. Recent evidence suggests that the mechanism responsible for this decline in proliferation involves a multi-organ genetic program. We hypothesized that this genetic program continues to progress into later adult life, eventually suppressing proliferation to levels below those needed for tissue renewal, thus contributing to aging. We therefore used expression microarray to compare the temporal changes in gene expression that occur in adult mouse organs during aging to those occurring as juvenile proliferation slows. We found that many of the changes in gene expression that occur during the aging process originate during the period of juvenile growth deceleration. Bioinformatic analyses of the genes that show persistent decline in expression throughout postnatal life indicated that cell-cycle-related genes are strongly over-represented. Thus, the findings support the hypothesis that the genetic program that slows juvenile growth to limit body size persists into adulthood and thus may eventually hamper tissue maintenance and repair, contributing to the aging process.
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Affiliation(s)
- Julian C Lui
- Developmental Endocrinology Branch, Program in Developmental Endocrinology and Genetics, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892-1103, USA.
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16
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Fernandez AA. A cancer-causing gene is positively correlated with male aggression in Xiphophorus cortezi. J Evol Biol 2009; 23:386-96. [PMID: 20021547 DOI: 10.1111/j.1420-9101.2009.01914.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
The persistence of seemingly maladaptive genes in organisms challenges evolutionary biological thought. In Xiphophorus fishes, certain melanin patterns form malignant melanomas because of a cancer-causing gene (Xiphophorus melanoma receptor kinase; Xmrk), which arose several millions years ago from unequal meiotic recombination. Xiphophorus melanomas are male biased and induced by androgens however male behaviour and Xmrk genotype has not been investigated. This study found that male X. cortezi with the spotted caudal (Sc) pattern, from which melanomas originate, displayed increased aggression in mirror image trials. Furthermore, Xmrk males (regardless of Sc phenotype) bit and performed more agonistic displays than Xmrk deficient males. Male aggressive response decreased when males viewed their Sc image as compared with their non-Sc image. Collectively, these results indicate that Xmrk males experience a competitive advantage over wild-type males and that intrasexual selection could be an important component in the evolutionary maintenance of this oncogene within Xiphophorus.
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Affiliation(s)
- A A Fernandez
- Department of Carcinogenesis, The University of Texas - M. D. Anderson Cancer Center; Science Park/Research Division; Smithville, TX, USA.
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17
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Maenhaut C, Dumont JE, Roger PP, van Staveren WCG. Cancer stem cells: a reality, a myth, a fuzzy concept or a misnomer? An analysis. Carcinogenesis 2009; 31:149-58. [PMID: 19858069 DOI: 10.1093/carcin/bgp259] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
The concept of cancer stem cells (CSC) embodies two aspects: the stem cell as the initial target of the oncogenic process and the existence of two populations of cells in cancers: the CSC and derived cells. The second is discussed in this review. CSC are defined as cells having three properties: a selectively endowed tumorigenic capacity, an ability to recreate the full repertoire of cancer cells of the parent tumor and the expression of a distinctive repertoire of surface biomarkers. In operational terms, the CSC are among all cancer cells those able to initiate a xenotransplant. Other explicit or implicit assumptions exist, including the concept of CSC as a single unique infrequent population of cells. To avoid such assumptions, we propose to use the operational term tumor-propagating cells (TPC); indeed, the cells that initiate transplants did not initiate the cancer. The experimental evidence supporting the explicit definition is analyzed. Cancers indeed contain a fraction of cells mainly responsible for the tumor development. However, there is evidence that these cells do not represent one homogenous population. Moreover, there is no evidence that the derived cells result from an asymmetric, qualitative and irreversible process. A more general model is proposed of which the CSC model could be one extreme case. We propose that the TPC are multiple evolutionary selected cancer cells with the most competitive properties [maintained by (epi-)genetic mechanisms], at least partially reversible, quantitative rather than qualitative and resulting from a stochastic rather than deterministic process.
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Affiliation(s)
- C Maenhaut
- Institute of Interdisciplinary Research (IRIBHM), School of Medicine, Université Libre de Bruxelles, Campus Erasme Hospital, Brussels, Belgium
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Susa D, De Bruin RWF, Mitchell JR, Roest HP, Hoeijmakers JHJ, Ijzermans JNM. Mechanisms of ageing in chronic allograft nephropathy. ACTA ACUST UNITED AC 2009. [DOI: 10.1080/17471060600756058] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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19
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Rhee W, Ray S, Yokoo H, Hoane ME, Lee CC, Mikheev AM, Horner PJ, Rostomily RC. Quantitative analysis of mitotic Olig2 cells in adult human brain and gliomas: implications for glioma histogenesis and biology. Glia 2009; 57:510-23. [PMID: 18837053 DOI: 10.1002/glia.20780] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
The capacity of adult human glial progenitor cells (AGPs), to proliferate and undergo multipotent differentiation, positions them as ideal candidate cells of origin for human gliomas. To investigate this potential role we identified AGPs as mitotically active Olig2 cells in nonneoplastic adult human brain and gliomas. We conservatively estimated that one in 5,000 human temporal lobe neocortical gray or subcortical white matter cells is mitotic. Extrapolating from a mean Olig2/Mib-1 labeling index (LI) of 52% and total cell number of 100 billion, we estimated the overall prevalence of mitotic Olig2 AGPs in nonneoplastic human brain parenchyma at 10 million. These data identify a large reservoir of Olig2 AGPs which could be potential targets for human gliomagenesis. The vast majority of mitotic cells in Grade II and Grade III gliomas of all histologic subtypes expressed Olig2 (mean LI 75%) but rarely S100B (LI 0.6%), identifying the Olig2 cell as a distinct contributor to the proliferating cell population of human gliomas of both oligodendroglial and astrocytic lineages. In the most malignant Grade IV glioma, or glioblastoma multiforme (GBM), the prevalence of Olig2/Mib-1 cells was significantly decreased (24.5%). The significantly lower Olig2/Mib-1 LI in GBMs suggests that a decrease in the prevalence of Olig2 cells to the total mitotic cell pool accompanies increasing malignancy. The novel framework provided by this quantitative and comparative analysis supports future studies to examine the histogenetic role of Olig2 AGPs in adult gliomas, their potential contribution to the tumor stroma and the molecular role of Olig2 in glioma pathogenesis.
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Affiliation(s)
- Wootack Rhee
- Department of Neurological Surgery, University of Washington School of Medicine, 1959 NE Pacific Street, Seattle,WA 98195-6470, USA
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Houben R, Ortmann S, Drasche A, Troppmair J, Herold MJ, Becker JC. Proliferation Arrest in B-Raf Mutant Melanoma Cell Lines upon MAPK Pathway Activation. J Invest Dermatol 2009; 129:406-14. [DOI: 10.1038/jid.2008.214] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
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21
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Choi NH, Kim JG, Yang DJ, Kim YS, Yoo MA. Age-related changes in Drosophila midgut are associated with PVF2, a PDGF/VEGF-like growth factor. Aging Cell 2008; 7:318-34. [PMID: 18284659 PMCID: PMC2408640 DOI: 10.1111/j.1474-9726.2008.00380.x] [Citation(s) in RCA: 198] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Age-associated changes in stem cell populations have been implicated in age-related diseases, including cancer. However, little is known about the underlying molecular mechanisms that link aging to the modulation of adult stem cell populations. Drosophila midgut is an excellent model system for the study of stem cell renewal and aging. Here we describe an age-related increase in the number and activity of intestinal stem cells (ISCs) and progenitor cells in Drosophila midgut. We determined that oxidative stress, induced by paraquat treatment or loss of catalase function, mimicked the changes associated with aging in the midgut. Furthermore, we discovered an age-related increase in the expression of PVF2, a Drosophila homologue of human PDGF/VEGF, which was associated with and required for the age-related changes in midgut ISCs and progenitor cell populations. Taken together, our findings suggest that PDGF/VEGF may play a central role in age-related changes in ISCs and progenitor cell populations, which may contribute to aging and the development of cancer stem cells.
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Affiliation(s)
- Na-Hyun Choi
- Department of Molecular Biology, College of Natural Science, Pusan National UniversityBusan 609-735, South Korea
| | - Joong-Gook Kim
- Department of Molecular Biology, College of Natural Science, Pusan National UniversityBusan 609-735, South Korea
| | - Dong-Jin Yang
- Department of Molecular Biology, College of Natural Science, Pusan National UniversityBusan 609-735, South Korea
| | - Young-Shin Kim
- Research Institute of Genetic Engineering, Pusan National UniversityBusan 609-735, South Korea
| | - Mi-Ae Yoo
- Department of Molecular Biology, College of Natural Science, Pusan National UniversityBusan 609-735, South Korea
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Genome-health nutrigenomics and nutrigenetics: nutritional requirements or ‘nutriomes’ for chromosomal stability and telomere maintenance at the individual level. Proc Nutr Soc 2008; 67:146-56. [DOI: 10.1017/s0029665108006988] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
It is becoming increasingly evident that (a) risk for developmental and degenerative disease increases with more DNA damage, which in turn is dependent on nutritional status, and (b) the optimal concentration of micronutrients for prevention of genome damage is also dependent on genetic polymorphisms that alter the function of genes involved directly or indirectly in the uptake and metabolism of micronutrients required for DNA repair and DNA replication. The development of dietary patterns, functional foods and supplements that are designed to improve genome-health maintenance in individuals with specific genetic backgrounds may provide an important contribution to an optimum health strategy based on the diagnosis and individualised nutritional prevention of genome damage, i.e. genome health clinics. The present review summarises some of the recent knowledge relating to micronutrients that are associated with chromosomal stability and provides some initial insights into the likely nutritional factors that may be expected to have an impact on the maintenance of telomeres. It is evident that developing effective strategies for defining nutrient doses and combinations or ‘nutriomes’ for genome-health maintenance at the individual level is essential for further progress in this research field.
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McGuckin CP, Forraz N. Potential for access to embryonic-like cells from human umbilical cord blood. Cell Prolif 2008; 41 Suppl 1:31-40. [PMID: 18181943 DOI: 10.1111/j.1365-2184.2008.00490.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
All too often media attention clouds the reality that there are many types of stem cell. The embryos, bone marrow and umbilical cord blood (UCB) are the three most used sources. However, despite what it would appear, embryonic stem cells have not been the first to yield life-saving cures at present. Faster routes to clinical intervention have been using adult stem cells that can be sourced from bone marrow and from cord blood, and that are readily accessible and are more ethically acceptable to the general public. Both these non-embryonic sources have been able to provide sufficient numbers of cells to allow development of clinical translational protocols. Bone marrow-derived cells have been used successfully in myocardial infarct therapy where relining by endothelial tissue has allowed limited reperfusion to damaged cardiac tissue. UCB have also demonstrated significant success for around 20 years in haematotransplantation. With a global human population in excess of 6 billion, births thus UCB, remain the largest untouched source of stem cells available every year. UCB also provide a distinct advantage over other adult stem cells due to the length of the telomere and also due protected immunological status of the developing neonatal environment. The total mutation load in the UCB populations is clearly likely to be significant less than in adult tissues.
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Affiliation(s)
- C P McGuckin
- Newcastle Centre for Cord Blood, Stem Cell Institute, Medical School, Newcastle upon Tyne, UK.
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Li N, Singh S, Cherukuri P, Li H, Yuan Z, Ellisen LW, Wang B, Robbins D, DiRenzo J. Reciprocal intraepithelial interactions between TP63 and hedgehog signaling regulate quiescence and activation of progenitor elaboration by mammary stem cells. Stem Cells 2008; 26:1253-64. [PMID: 18292212 DOI: 10.1634/stemcells.2007-0691] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
TP63 is required for preservation of epithelial regenerative stasis and regulates the activity of diverse genetic pathways; however, specific effector pathways are poorly understood. Data presented here indicate that reciprocal regulatory interactions between hedgehog signaling and TP63 mediate stage-specific effects on proliferation and clonigenicity of separable enriched mammary stem and progenitor fractions. Analysis of DeltaN-p63 and TA-p63 indicates segregated expression in mammary stem and progenitor fractions, respectively, demonstrating that differential TP63 promoter selection occurs during elaboration of mammary progenitors by mammary stem cells. This segregation underlies mammary progenitor-specific expression of Indian Hedgehog, identifying it as a binary transcriptional target of TP63. Hedgehog activation in vivo enhances elaboration of mammary progenitors and decreases label retention within mammary stem cell-enriched fractions, suggesting that hedgehog exerts a mitogenic effect on mammary stem cells. Hedgehog signaling promotes differential TP63 promoter usage via disruption of Gli3 or Gli3(R) accumulation, and shRNA-mediated disruption of Gli3 expression was sufficient to alter TP63 promoter usage and enhance clonigenicity of mammary stem cells. Finally, hedgehog signaling is enhanced during pregnancy, where it contributes to expansion of the mammary progenitor compartment. These studies support a model in which hedgehog activates elaboration and differentiation of mammary progenitors via differential TP63 promoter selection and forfeiture of self-renewing capacity.
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Affiliation(s)
- Na Li
- Department of Pharmacology and Toxicology, Dartmouth Medical School, 7650 Remsen, Hanover, New Hampshire 03755, USA
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25
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Stindl R. Defining the steps that lead to cancer: replicative telomere erosion, aneuploidy and an epigenetic maturation arrest of tissue stem cells. Med Hypotheses 2008; 71:126-40. [PMID: 18294777 DOI: 10.1016/j.mehy.2008.01.010] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2008] [Revised: 01/04/2008] [Accepted: 01/07/2008] [Indexed: 01/21/2023]
Abstract
Recently, an influential sequencing study found that more than 1700 genes had non-silent mutations in either a breast or colorectal cancer, out of just 11 breast and 11 colorectal tumor samples. This is not surprising given the fact that genomic instability is the hallmark of cancer cells. The plethora of genomic alterations found in every carcinoma does not obey the 'law of genotype-phenotype correlation', since the same histological subtype of cancer harbors different gene mutations and chromosomal aberrations in every patient. In an attempt to make sense out of the observed genetic and chromosomal chaos in cancer, I propose a cascade model. According to this model, tissue regeneration depends on the proliferation and serial activation of stem cells. Replicative telomere erosion limits the proliferative life span of adult stem cells and results in the Hayflick limit (M1). However, local tissue exhaustion or old age might promote the activation of M1-deficient tissue stem cells. Extended proliferation of these cells leads to telomere-driven chromosomal instability and aneuploidy (abnormal balance of chromosomes and/or chromosome material). Several of the aforementioned steps have been already described in the literature. However, in contrast to common theories, it is proposed here that the genomic damage blocks the epigenetic differentiation switch. As a result of aneuploidy, differentiation-specific genes cannot be activated by modification of methylation patterns. Consequently, the phenotype of cancer tissue is largely determined by the epigenetic maturation arrest of tissue stem cells, which in addition enables a fraction of cancer cells to proliferate, invade and metastasize, as normal adult stem cells do. The new model combines genetic and epigenetic alterations of cancer cells in one causative cascade and offers an explanation for why identical histologic cancer types harbor a confusing variety of chromosomal and gene aberrations. The Viennese Cascade, as presented here, may end the debate on if and how 'tumor-unspecific' aneuploidy leads to cancer.
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Affiliation(s)
- Reinhard Stindl
- Department of Molecular and Cell Biology, 353 Donner Hall, University of California at Berkeley, Berkeley, CA 94720-3206, USA.
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26
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Foroni C, Galli R, Cipelletti B, Caumo A, Alberti S, Fiocco R, Vescovi A. Resilience to transformation and inherent genetic and functional stability of adult neural stem cells ex vivo. Cancer Res 2007; 67:3725-33. [PMID: 17440085 DOI: 10.1158/0008-5472.can-06-4577] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Recent observations have suggested that extensive culturing of adult neural stem cells (ANSCs) by exploiting the NeuroSphere assay might select for aggressive cell clones, endowed with neoplastic potential, that overgrow the rest of the native stem cells. However, a detailed study of the propensity of ANSCs to transform has never been thoroughly undertaken. Here, we report the first demonstration that ANSCs can be propagated in vitro for over a year, maintaining a strikingly stable profile with regard to self-renewal, differentiation, growth factor dependence, karyotype, and molecular profiling. Most importantly, the long-term culturing of ANSCs did not result in the formation of tumors in vivo, even when ANSCs were transduced with Myc and Ras oncogenes. The cancer resistance could depend on specific mechanisms aimed at protecting ANSCs and preserved by optimal nonstressful culture conditions. In conclusion, besides a plentiful and safe source of cells for therapeutic applications, ANSCs provide an ideal model to study aging and cancer in the context of stemness.
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Affiliation(s)
- Chiara Foroni
- Stem Cell Research Institute-DIBIT, San Raffaele Scientific Institute, Milan, Italy
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27
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Zhang Z, Jin L, Qian X, Wei M, Wang Y, Wang J, Yang Y, Xu Q, Xu Y, Liu F. Novel Bcl-2 Inhibitors: Discovery and Mechanism Study of Small Organic Apoptosis-Inducing Agents. Chembiochem 2007; 8:113-21. [PMID: 17139689 DOI: 10.1002/cbic.200600305] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Apoptosis as a novel target for cancer chemotherapy has generated an intense demand for new apoptosis-inducing agents. The newly revealed role of protein families involved in the apoptosis pathway, and resistance to cytotoxic therapies have opened new avenues for the development of novel anticancer strategies. We have established a novel strategy to rapidly obtain protein-targeted, instead of conventional DNA-targeted, apoptosis inducers as antitumor leads. First, a novel organic non-DNA intercalative compound S1 (8-oxo-3-thiomorpholin-4-yl-8H-acenaphtho[1,2-b]pyrrole-9-carbonitrile, M(W) = 331) was found with an IC50 of 10(-7)-10(-8) microM against diverse cancer cell lines. Further biological evaluation demonstrated that it was an apoptosis-inducer both in vivo and in vitro. The treatment of hydroperitoneum hepatoma cells (H22 cell line) with S1 at various concentrations (from 0.01 to 10 microM) for 24 h triggered these cells to enter the apoptosis process. The antitumor efficiency was also tested in the H22 xenotransplant models in mice. At a dosage of 0.3 mg kg(-1), S1 exhibited significant antitumor activity with a much longer survival time, a decrease in tumor size, and increased apoptosis cells in tumor tissue. More importantly, studies of the molecular mechanism of apoptosis induction by S1 revealed that S1 inactivated the Bcl-2 protein by binding to it, depolarizing the mitochondrial membrane, and then activating caspase 9, followed by caspase 3. Finally, structure-based virtual modification was performed by computer modeling. As a result, a derivative, S2 (8-oxo-3-[(thienylmethyl)amino]-8H-acenaphtho[1,2-b]pyrrole-9-carbonitrile, M(W) = 341) was identified that possessed a lower binding energy to Bcl-2, and demonstrated better antitumor potency, even on the Bcl-2-overexpressing human acute myeloid leukemia (HL-60) cells (IC50 = 1.3 microM) in vitro. S1 and S2 are the well-defined Bcl-2 inhibitors that give us a promising platform for the development of new therapeutic agents.
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Affiliation(s)
- Zhichao Zhang
- State Key Laboratory of Fine Chemicals, Dalian University of Technology, Dalian 116012, China.
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29
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Wodarz D. Effect of stem cell turnover rates on protection against cancer and aging. J Theor Biol 2006; 245:449-58. [PMID: 17178130 DOI: 10.1016/j.jtbi.2006.10.013] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2006] [Revised: 10/05/2006] [Accepted: 10/16/2006] [Indexed: 12/12/2022]
Abstract
Tissue stem cells are responsible for replenishing and maintaining a population of cells which make up a functioning organ. They divide by asymmetric cell division where one daughter remains a stem cell while the other daughter becomes a transit cell, which divides a defined number of times and differentiates. A fully differentiated cell has a finite life-span. A tissue can be maintained by various strategies. Stem cells can divide often and differentiated cells die often (fast turnover). Alternatively, stem cells can divide infrequently, and the differentiated cells are long lived (slow turnover). Genetic alterations and mutations can interfere with tissue homoeostasis. Mutations can induce senescence and apoptosis, and this can result in a reduction of the number of functioning tissue cells which could correlate with tissue aging. Alternatively, mutations can result in the carcinogenic transformation of cells and the formation of a tumour. Using mathematical models, I find that the cellular turnover rate affects the ability of genetic alterations to induce aging and the development of cancer. If mutations occur as a result of errors during cell division, the model suggests that a low cellular turnover rate protects both against aging and the development of cancer. On the other hand, if mutations occur independent from cell division (e.g. if DNA is hit by damaging agents), I find that a high cellular turnover rate protects against aging, while it promotes the development of cancer. Implications for optimal tissue design are discussed.
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Affiliation(s)
- Dominik Wodarz
- Department of Ecology and Evolution, 321 Steinhaus Hall, University of California, Irvine, CA 92697, USA.
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30
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Daniels JT, Harris AR, Mason C. Corneal epithelial stem cells in health and disease. ACTA ACUST UNITED AC 2006; 2:247-54. [PMID: 17625261 DOI: 10.1007/s12015-006-0053-4] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/1999] [Revised: 11/30/1999] [Accepted: 11/30/1999] [Indexed: 12/15/2022]
Abstract
The cornea on the front surface of the eye provides our window to the world. Maintenance of corneal transparency is dependent on the integrity and functionality of the outermost corneal epithelium which itself is maintained throughout life by a population of limbal epithelial stem cells (LESC). If this adult stem cell population is depleted by injury or disease, the transparency of the cornea and therefore vision is threatened. LESC deficiency results in corneal opacification, inflammation, vascularization, and severe discomfort. Cultured LESC therapy is one of only several examples of the successful use of an adult stem cell therapy in patients. Hence, the ready accessibility of a transparent stem cell niche and the clinical precedence for use of stem cell therapy make the cornea a unique and excellent model for the study of adult stem cells in health and disease. This review will discuss our current understanding of LESC biology, pathology, and therapeutic application.
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Affiliation(s)
- Julie T Daniels
- Cells for Sight Transplantation and Research Programme, Ocular Repair and Regeneration Biology Unit, Division of Pathology, UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL
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31
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Feldmann RE, Mattern R. The human brain and its neural stem cells postmortem: from dead brains to live therapy. Int J Legal Med 2005; 120:201-11. [PMID: 16211420 DOI: 10.1007/s00414-005-0037-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2005] [Accepted: 08/02/2005] [Indexed: 12/21/2022]
Abstract
Contrary to the traditional dogma of being a relatively invariable and quiescent organ lacking the capability to regenerate, there is now widespread evidence that the human brain harbors multipotent neural stem cells, possibly throughout senescence. These cells can divide and give rise to neuroectodermal progeny in vivo and are now regarded as powerful prospective candidates for repairing or enhancing the functional capability of neural tissue in trauma or diseases associated with degeneration or malperfusion. Hopes primarily rest upon techniques to either recruit endogenous stem cells or to utilize exogenous donor-derived material for transplantation. In the search for suitable human cell sources, embryonic, fetal, and adult stem cells appear highly controversial, as they are accompanied by various still-unresolved moral and legal challenges. Fascinatingly, however, recent reports indicate the successful isolation and expansion of viable neural stem cells from the rodent and human brain within a considerable postmortem interval, suggesting that postmortem neural stem cells could potentially become an acceptable alternative cellular resource. This article will provide a brief overview about neural stem cells, their prominent features, and prospects for a cellular therapy, and will furthermore illuminate the cells in particular with respect to their newly discovered postmortem provenience, their advantage as a potential cell source, and several unfolding forensic considerations. Also, important ethical, social, and legal implications arising from this hitherto unpracticed cellular harvest of brain tissue from the deceased are outlined.
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Affiliation(s)
- Robert E Feldmann
- Department of Psychiatry, Division of Neurobiology, The Johns Hopkins University Medical Institutions, Children's Medical and Surgical Center (CMSC), 9-115 1800 E. Jefferson Street, Baltimore, MD 21287, USA.
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