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Cheng H, Zou Y, Shah CD, Fan N, Bhagat TD, Gucalp R, Kim M, Verma A, Piperdi B, Spivack SD, Halmos B, Perez-Soler R. First-in-human study of inhaled Azacitidine in patients with advanced non-small cell lung cancer. Lung Cancer 2021; 154:99-104. [PMID: 33636454 DOI: 10.1016/j.lungcan.2021.02.015] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2021] [Revised: 02/02/2021] [Accepted: 02/12/2021] [Indexed: 01/19/2023]
Abstract
BACKGROUND Aerosolized Azacitidine has been shown to inhibit orthotopic lung cancer growth and induce re-expression of methylated tumor suppressor genes in murine models. We hypothesized that inhaled Azacitidine is safe and effective in reversing epigenetic changes in the bronchial epithelium secondary to chronic smoking. PATIENTS AND METHODS We report the first in human study of inhaled Azacitidine. Azacitidine in aqueous solution was used to generate an aerosol suspension of 0.25-5 μm particle size. Main inclusion criteria: Stage IV or recurrent NSCLC with predominantly lung involvement, ≥1 prior systemic therapy, ECOG PS 0-1, and adequate pulmonary function. Patients received inhaled Azacitidine daily on days 1-5 and 15-19 of 28-day cycles, at 3 escalating doses (15, 30 and 45 mg/m2 daily). The primary objective was to determine the feasibility and tolerability of this new therapeutic modality. The key secondary objectives included pharmacokinetics, methylation profiles and efficacy. RESULTS From 3/2015 to 2/2018, eight patients received a median number of 2 (IQR = 1) cycles of inhaled Azacitidine. No clinically significant adverse events were observed, except one patient treated at the highest dose developed an asymptomatic grade 2 decreased DLCO which resolved spontaneously. One patient receiving 12 cycles of therapy had an objective and durable partial response, and two patients had stable disease. Plasma Azacitidine was only briefly detectable in patients treated at the higher doses. Moreover, in 2 of 3 participants who agreed and underwent pre- and post-treatment bronchoscopy, the global DNA methylation in the bronchial epithelium decreased by 24 % and 79 % post-therapy, respectively. The interval between last inhaled treatment and bronchoscopy was 3 days. CONCLUSIONS Inhaled Azacitidine resulted in negligible plasma levels compared to the previously reported subcutaneous administration and was well-tolerated. The results justify the continued development of inhaled Azacitidine at non-cytotoxic doses for patients with lung-confined malignant and/or premalignant lesions.
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Affiliation(s)
- Haiying Cheng
- Department of Oncology, Montefiore Medical Center/Albert Einstein College of Medicine, Bronx, NY10461, USA.
| | - Yiyu Zou
- Department of Oncology, Montefiore Medical Center/Albert Einstein College of Medicine, Bronx, NY10461, USA
| | - Chirag D Shah
- Division of Pulmonary Medicine, Montefiore Medical Center/Albert Einstein College of Medicine, Bronx, NY10461, USA
| | - Ni Fan
- Department of Oncology, Montefiore Medical Center/Albert Einstein College of Medicine, Bronx, NY10461, USA
| | - Tushar D Bhagat
- Department of Oncology, Montefiore Medical Center/Albert Einstein College of Medicine, Bronx, NY10461, USA
| | - Rasim Gucalp
- Department of Oncology, Montefiore Medical Center/Albert Einstein College of Medicine, Bronx, NY10461, USA
| | - Mimi Kim
- Department of Epidemiology & Population Health, Albert Einstein College of Medicine, Bronx, NY10461, USA
| | - Amit Verma
- Department of Oncology, Montefiore Medical Center/Albert Einstein College of Medicine, Bronx, NY10461, USA
| | | | - Simon D Spivack
- Division of Pulmonary Medicine, Montefiore Medical Center/Albert Einstein College of Medicine, Bronx, NY10461, USA
| | - Balazs Halmos
- Department of Oncology, Montefiore Medical Center/Albert Einstein College of Medicine, Bronx, NY10461, USA
| | - Roman Perez-Soler
- Department of Oncology, Montefiore Medical Center/Albert Einstein College of Medicine, Bronx, NY10461, USA.
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Proshkina E, Shaposhnikov M, Moskalev A. Genome-Protecting Compounds as Potential Geroprotectors. Int J Mol Sci 2020; 21:E4484. [PMID: 32599754 PMCID: PMC7350017 DOI: 10.3390/ijms21124484] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2020] [Revised: 06/18/2020] [Accepted: 06/19/2020] [Indexed: 02/06/2023] Open
Abstract
Throughout life, organisms are exposed to various exogenous and endogenous factors that cause DNA damages and somatic mutations provoking genomic instability. At a young age, compensatory mechanisms of genome protection are activated to prevent phenotypic and functional changes. However, the increasing stress and age-related deterioration in the functioning of these mechanisms result in damage accumulation, overcoming the functional threshold. This leads to aging and the development of age-related diseases. There are several ways to counteract these changes: 1) prevention of DNA damage through stimulation of antioxidant and detoxification systems, as well as transition metal chelation; 2) regulation of DNA methylation, chromatin structure, non-coding RNA activity and prevention of nuclear architecture alterations; 3) improving DNA damage response and repair; 4) selective removal of damaged non-functional and senescent cells. In the article, we have reviewed data about the effects of various trace elements, vitamins, polyphenols, terpenes, and other phytochemicals, as well as a number of synthetic pharmacological substances in these ways. Most of the compounds demonstrate the geroprotective potential and increase the lifespan in model organisms. However, their genome-protecting effects are non-selective and often are conditioned by hormesis. Consequently, the development of selective drugs targeting genome protection is an advanced direction.
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Affiliation(s)
- Ekaterina Proshkina
- Laboratory of Geroprotective and Radioprotective Technologies, Institute of Biology, Komi Science Centre, Ural Branch, Russian Academy of Sciences, 28 Kommunisticheskaya st., 167982 Syktyvkar, Russia; (E.P.); (M.S.)
| | - Mikhail Shaposhnikov
- Laboratory of Geroprotective and Radioprotective Technologies, Institute of Biology, Komi Science Centre, Ural Branch, Russian Academy of Sciences, 28 Kommunisticheskaya st., 167982 Syktyvkar, Russia; (E.P.); (M.S.)
| | - Alexey Moskalev
- Laboratory of Geroprotective and Radioprotective Technologies, Institute of Biology, Komi Science Centre, Ural Branch, Russian Academy of Sciences, 28 Kommunisticheskaya st., 167982 Syktyvkar, Russia; (E.P.); (M.S.)
- Pitirim Sorokin Syktyvkar State University, 55 Oktyabrsky prosp., 167001 Syktyvkar, Russia
- Center for Precision Genome Editing and Genetic Technologies for Biomedicine, Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, 119991 Moscow, Russia
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Kaur G, Begum R, Thota S, Batra S. A systematic review of smoking-related epigenetic alterations. Arch Toxicol 2019; 93:2715-2740. [PMID: 31555878 DOI: 10.1007/s00204-019-02562-y] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2019] [Accepted: 09/02/2019] [Indexed: 02/06/2023]
Abstract
The aim of this study is to provide a systematic review of the known epigenetic alterations caused by cigarette smoke; establish an evidence-based perspective of their clinical value for screening, diagnosis, and treatment of smoke-related disorders; and discuss the challenges and ethical concerns associated with epigenetic studies. A well-defined, reproducible search strategy was employed to identify relevant literature (clinical, cellular, and animal-based) between 2000 and 2019 based on AMSTAR guidelines. A total of 80 studies were identified that reported alterations in DNA methylation, histone modifications, and miRNA expression following exposure to cigarette smoke. Changes in DNA methylation were most extensively documented for genes including AHRR, F2RL3, DAPK, and p16 after exposure to cigarette smoke. Likewise, miR16, miR21, miR146, and miR222 were identified to be differentially expressed in smokers and exhibit potential as biomarkers for determining susceptibility to COPD. We also identified 22 studies highlighting the transgenerational effects of maternal and paternal smoking on offspring. This systematic review lists the epigenetic events/alterations known to occur in response to cigarette smoke exposure and identifies the major genes and miRNAs that are potential targets for translational research in associated pathologies. Importantly, the limitations and ethical concerns related to epigenetic studies are also highlighted, as are the effects on the ability to address specific questions associated with exposure to tobacco/cigarette smoke. In the future, improved interpretation of epigenetic signatures will lead to their increased use as biomarkers and/or in drug development.
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Affiliation(s)
- Gagandeep Kaur
- Laboratory of Pulmonary Immuno-toxicology, Department of Environmental Toxicology, 129 Health Research Centre, Southern University and A&M College, Baton Rouge, LA, 70813, USA
| | - Rizwana Begum
- Laboratory of Pulmonary Immuno-toxicology, Department of Environmental Toxicology, 129 Health Research Centre, Southern University and A&M College, Baton Rouge, LA, 70813, USA
| | - Shilpa Thota
- Laboratory of Pulmonary Immuno-toxicology, Department of Environmental Toxicology, 129 Health Research Centre, Southern University and A&M College, Baton Rouge, LA, 70813, USA
| | - Sanjay Batra
- Laboratory of Pulmonary Immuno-toxicology, Department of Environmental Toxicology, 129 Health Research Centre, Southern University and A&M College, Baton Rouge, LA, 70813, USA.
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Fragou D, Pakkidi E, Aschner M, Samanidou V, Kovatsi L. Smoking and DNA methylation: Correlation of methylation with smoking behavior and association with diseases and fetus development following prenatal exposure. Food Chem Toxicol 2019; 129:312-327. [PMID: 31063835 DOI: 10.1016/j.fct.2019.04.059] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2018] [Revised: 04/29/2019] [Accepted: 04/30/2019] [Indexed: 12/13/2022]
Abstract
Among epigenetic mechanisms, DNA methylation has been widely studied with respect to many environmental factors. Smoking is a common factor which affects both global and gene-specific DNA methylation. It is supported that smoking directly affects DNA methylation, and these effects contribute to the development and progression of various diseases, such as cancer, lung and cardiovascular diseases and male infertility. In addition, prenatal smoking influences the normal development of the fetus via DNA methylation changes. The DNA methylation profile and its smoking-induced alterations helps to distinguish current from former smokers and non-smokers and can be used to predict the risk for the development of a disease. This review summarizes the DNA methylation changes induced by smoking, their correlation with smoking behavior and their association with various diseases and fetus development.
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Affiliation(s)
- Domniki Fragou
- Laboratory of Forensic Medicine and Toxicology, School of Medicine, Aristotle University of Thessaloniki, Greece
| | - Eleni Pakkidi
- Laboratory of Analytical Chemistry, Department of Chemistry, Aristotle University of Thessaloniki, Greece
| | - Michael Aschner
- Departments of Molecular Pharmacology, Neuroscience, and Pediatrics, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Victoria Samanidou
- Laboratory of Analytical Chemistry, Department of Chemistry, Aristotle University of Thessaloniki, Greece
| | - Leda Kovatsi
- Laboratory of Forensic Medicine and Toxicology, School of Medicine, Aristotle University of Thessaloniki, Greece.
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Ghosh M, Öner D, Poels K, Tabish AM, Vlaanderen J, Pronk A, Kuijpers E, Lan Q, Vermeulen R, Bekaert B, Hoet PH, Godderis L. Changes in DNA methylation induced by multi-walled carbon nanotube exposure in the workplace. Nanotoxicology 2017; 11:1195-1210. [PMID: 29191063 DOI: 10.1080/17435390.2017.1406169] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
This study was designed to assess the epigenetic alterations in blood cells, induced by occupational exposure to multi-wall carbon nanotubes (MWCNT). The study population comprised of MWCNT-exposed workers (n=24) and unexposed controls (n=43) from the same workplace. We measured global DNA methylation/hydroxymethylation levels on the 5th cytosine residues using a validated liquid chromatography tandem-mass spectrometry (LC-MS/MS) method. Sequence-specific methylation of LINE1 retrotransposable element 1 (L1RE1) elements, and promoter regions of functionally important genes associated with epigenetic regulation [DNA methyltransferase-1 (DNMT1) and histone deacetylase 4 (HDAC4)], DNA damage/repair and cell cycle pathways [nuclear protein, coactivator of histone transcription/ATM serine/threonine kinase (NPAT/ATM)], and a potential transforming growth factor beta (TGF-β) repressor [SKI proto-oncogene (SKI)] were studied using bisulfite pyrosequencing. Analysis of global DNA methylation levels and hydroxymethylation did not reveal significant difference between the MWCNT-exposed and control groups. No significant changes in Cytosine-phosphate-Guanine (CpG) site methylation were observed for the LINE1 (L1RE1) elements. Further analysis of gene-specific DNA methylation showed a significant change in methylation for DNMT1, ATM, SKI, and HDAC4 promoter CpGs in MWCNT-exposed workers. Since DNA methylation plays an important role in silencing/regulation of the genes, and many of these genes have been associated with occupational and smoking-induced diseases and cancer (risk), aberrant methylation of these genes might have a potential effect in MWCNT-exposed workers.
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Affiliation(s)
- Manosij Ghosh
- a Department of Public Health and Primary Care, Centre Environment & Health , KU Leuven , Leuven , Belgium
| | - Deniz Öner
- a Department of Public Health and Primary Care, Centre Environment & Health , KU Leuven , Leuven , Belgium
| | - Katrien Poels
- a Department of Public Health and Primary Care, Centre Environment & Health , KU Leuven , Leuven , Belgium
| | - Ali M Tabish
- a Department of Public Health and Primary Care, Centre Environment & Health , KU Leuven , Leuven , Belgium
| | - Jelle Vlaanderen
- b Division of Environmental Epidemiology, Institute for Risk Assessment Sciences , Utrecht University , Utrecht , The Netherlands
| | - Anjoeka Pronk
- c TNO, Netherlands Organisation for Applied Scientific Research , Zeist , The Netherlands
| | - Eelco Kuijpers
- c TNO, Netherlands Organisation for Applied Scientific Research , Zeist , The Netherlands
| | - Qing Lan
- d Occupational and Environmental Epidemiology Branch, Division of Cancer Epidemiology and Genetics , National Cancer Institute , Bethesda , MD , USA
| | - Roel Vermeulen
- b Division of Environmental Epidemiology, Institute for Risk Assessment Sciences , Utrecht University , Utrecht , The Netherlands
| | - Bram Bekaert
- e Department of Forensic Medicine, Laboratory of Forensic Genetics and Molecular Archaeology , University Hospitals Leuven , Leuven , Belgium
| | - Peter Hm Hoet
- a Department of Public Health and Primary Care, Centre Environment & Health , KU Leuven , Leuven , Belgium
| | - Lode Godderis
- a Department of Public Health and Primary Care, Centre Environment & Health , KU Leuven , Leuven , Belgium.,f External Service for Prevention and Protection at Work , Idewe , Heverlee , Belgium
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Bokaba RP, Anderson R, Theron AJ, Tintinger GR. Cigarette smoke condensate attenuates phorbol ester-mediated neutrophil extracellular trap formation. Afr Health Sci 2017; 17:896-904. [PMID: 29085418 PMCID: PMC5656221 DOI: 10.4314/ahs.v17i3.33] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
BACKGROUND Neutrophil extracellular traps (NETs) constitute a network of chromatin fibres containing histone and antimicrobial peptides that are released by activated neutrophils. NETs protect the host against infection by trapping and facilitating phagocytosis of potentially harmful pathogens. OBJECTIVES The aim of the current study was to investigate the effects of cigarette smoke condensate (CSC) on phorbol-ester (PMA)-mediated NETosis in vitro. METHODS Isolated human blood neutrophils were exposed to PMA (6.25 ng/ml) in the presence or absence of CSC (40-80 µg/ml) for 90 min at 37oC. NET formation was measured using a spectrofluorimetric procedure to detect extracellular DNA and fluorescence microscopy was used to visualize nets. Oxygen consumption by PMA-activated neutrophils was measured using an oxygen sensitive electrode. RESULTS Activation of neutrophils with PMA was associated with induction of NETosis that was significantly attenuated in the presence of CSC (40 and 80 µg/ml), with mean fluorescence intensities of 65% and 66% of that observed with untreated cells, respectively, and confirmed by fluorescence microscopy. The rate and magnitude of oxygen consumption by activated neutrophils pre-treated with CSC (80 µg/ml) was significantly less than that observed with untreated cells (73% of the control system), indicative of decreased production of reactive oxidants in the presence of CSC. CONCLUSION The inhibition of NETosis observed in the presence of CSC correlated with attenuation of oxygen consumption by PMA-activated neutrophils suggesting a mechanistic relationship between these events. If operative in vivo, smoking-related attenuation of NETosis may impair host immune responses and increase the risk of respiratory infections.
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Affiliation(s)
| | - Ronald Anderson
- Institute for Cellular and Molecular Medicine, SAMRC Extramural Unit for Stem Cell Research and Therapy, Department of Immunology, Faculty of Health Sciences, University of Pretoria, Pretoria, South Africa
| | - Annette Johanna Theron
- Department of Immunology, Faculty of Health Sciences, University of Pretoria, Pretoria, South Africa
- Tshwane Academic Division of the National Health Laboratory Service, Pretoria South Africa
| | - Gregory Ronald Tintinger
- Department of Internal Medicine, University of Pretoria and Steve Biko Academic Hospital, Pretoria, South Africa
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7
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AGTR1 promoter hypermethylation in lung squamous cell carcinoma but not in lung adenocarcinoma. Oncol Lett 2017; 14:4989-4994. [PMID: 29085512 DOI: 10.3892/ol.2017.6824] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2016] [Accepted: 08/03/2017] [Indexed: 12/23/2022] Open
Abstract
Aberrant DNA methylation is associated with non-small cell lung cancer (NSCLC), suggesting that gene promoter methylation may be a potential biomarker for the detection or risk prediction of NSCLC. The present study aimed to evaluate the potential usage of angiotensin II receptor type 1 (AGTR1) methylation in two major pathologic subtypes: Lung adenocarcinoma (LUAD) and lung squamous cell carcinoma (LUSC). Quantitative methylation-specific polymerase chain reaction was used to investigate the effect of AGTR1 promoter methylation in the tumor and the paired adjacent non-tumor tissue samples from 42 patients with LUSC, and 69 with LUAD. The percentage of methylated reference was calculated and presented as the median (interquartile range 25th-75th percentile). The results of the current study revealed that there was significantly increased AGTR1 promoter methylation in the tumor tissues compared with the paired adjacent non-tumor tissue [97.4 (57.22-130.5) vs. 85 (48.25-123); P=0.024]. Furthermore, higher AGTR1 promoter methylation was observed in patients with LUSC compared with LUAD (odds ratio=2.483; 95% confidence interval=1.125-5.480; P=0.023). Significant differences were identified in AGTR1 methylation between non-tumor and the tumor tissues in LUSC [113.5 (68.33-148.73) vs. 93.04 (45.94-140); P=0.008]. In addition, the Cancer Genome Atlas data of 378 patients with LUSC and 477 with LUAD revealed an inverse correlation between gene expression and the methylation status of AGTR1 promoter.. These data suggest that AGTR1 hypermethylation is a promising biomarker to assist in LUSC detection and diagnosis.
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Helling BA, Gerber AN, Kadiyala V, Sasse SK, Pedersen BS, Sparks L, Nakano Y, Okamoto T, Evans CM, Yang IV, Schwartz DA. Regulation of MUC5B Expression in Idiopathic Pulmonary Fibrosis. Am J Respir Cell Mol Biol 2017; 57:91-99. [PMID: 28272906 DOI: 10.1165/rcmb.2017-0046oc] [Citation(s) in RCA: 59] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
The gain-of-function mucin 5B (MUC5B) promoter variant, rs35705950, confers the largest risk, genetic or otherwise, for the development of idiopathic pulmonary fibrosis; however, the mechanisms underlying the regulation of MUC5B expression have yet to be elucidated. Here, we identify a critical regulatory domain that contains the MUC5B promoter variant and has a highly conserved forkhead box protein A2 (FOXA2) binding motif. This region is differentially methylated in association with idiopathic pulmonary fibrosis, MUC5B expression, and rs35705950. In addition, we show that this locus binds FOXA2 dynamically, and that binding of FOXA2 is necessary for enhanced expression of MUC5B. In aggregate, our findings identify novel targets to regulate the expression of MUC5B.
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Affiliation(s)
- Britney A Helling
- 1 Department of Medicine, School of Medicine, University of Colorado-Denver, Denver, Colorado
| | - Anthony N Gerber
- 1 Department of Medicine, School of Medicine, University of Colorado-Denver, Denver, Colorado.,2 Department of Medicine, National Jewish Health, Denver, Colorado; and
| | - Vineela Kadiyala
- 2 Department of Medicine, National Jewish Health, Denver, Colorado; and
| | - Sarah K Sasse
- 2 Department of Medicine, National Jewish Health, Denver, Colorado; and
| | - Brent S Pedersen
- 1 Department of Medicine, School of Medicine, University of Colorado-Denver, Denver, Colorado
| | - Lenore Sparks
- 1 Department of Medicine, School of Medicine, University of Colorado-Denver, Denver, Colorado
| | - Yasushi Nakano
- 1 Department of Medicine, School of Medicine, University of Colorado-Denver, Denver, Colorado
| | - Tsukasa Okamoto
- 1 Department of Medicine, School of Medicine, University of Colorado-Denver, Denver, Colorado
| | - Christopher M Evans
- 1 Department of Medicine, School of Medicine, University of Colorado-Denver, Denver, Colorado
| | - Ivana V Yang
- 1 Department of Medicine, School of Medicine, University of Colorado-Denver, Denver, Colorado.,3 University of Colorado-Denver, School of Public Health, Denver, Colorado
| | - David A Schwartz
- 1 Department of Medicine, School of Medicine, University of Colorado-Denver, Denver, Colorado.,2 Department of Medicine, National Jewish Health, Denver, Colorado; and
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Yang Y, Yin W, Wu F, Fan J. Combination of azacitidine and trichostatin A decreased the tumorigenic potential of lung cancer cells. Onco Targets Ther 2017; 10:2993-2999. [PMID: 28652781 PMCID: PMC5476757 DOI: 10.2147/ott.s136218] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Purpose This study aims to investigate the possibility of using epigenetic inhibitors against lung cancer. Methods The changes in the proliferation of human lung cancer cells, NCI-H1975 and NCI-H1299 cells, treated with various doses of inhibitors of DNA methyltransferase (azacitidine [5-AZA]) or histone deacetylase inhibitors (trichostatin A [TSA]) were determined by cell counting. The cell viability of NCI-H1975 and NCI-H1299 cells treated with 5-AZA and/or TSA was measured by the MTT assay. The changes in expression of the AKT signaling pathway molecules caused by the application of 5-AZA and TSA were analyzed through their protein and mRNA levels. A xenograft model was used to observe the effects of 5-AZA and TSA on tumor growth in vivo. Results 5-AZA and TSA inhibited the proliferation and viability of NCI-H1975 and NCI-H1299 cells. Their joint application significantly influenced the expression of key molecules in AKT signaling pathway in vitro, and inhibited the growth of xenograft tumors in vivo. Furthermore, TSA and 5-AZA decreased the tumorigenic ability of NCI-H1975 cells in vivo. Conclusion The decreased cell viability and tumorigenic ability, as well as increased anti-oncogene expression following the joint application of 5-AZA and TSA, make these epigenetic inhibitors prospective therapeutic agents for lung cancer.
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Affiliation(s)
- Yang Yang
- Department of Thoracic Surgery, Shanghai Pulmonary Hospital, Tongji University, Shanghai, China
| | - Wei Yin
- Key Laboratory of Oral Biomedical Engineering of Ministry of Education, Hospital of Stomatology, School of Stomatology, Wuhan University, Wuhan, China
| | - Fengying Wu
- Oncology Department, Shanghai Pulmonary Hospital, Tongji University, Shanghai, China
| | - Jiang Fan
- Department of Thoracic Surgery, Shanghai Pulmonary Hospital, Tongji University, Shanghai, China
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Mills AA. The Chromodomain Helicase DNA-Binding Chromatin Remodelers: Family Traits that Protect from and Promote Cancer. Cold Spring Harb Perspect Med 2017; 7:cshperspect.a026450. [PMID: 28096241 DOI: 10.1101/cshperspect.a026450] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
A plethora of mutations in chromatin regulators in diverse human cancers is emerging, attesting to the pivotal role of chromatin dynamics in tumorigenesis. A recurrent theme is inactivation of the chromodomain helicase DNA-binding (CHD) family of proteins-ATP-dependent chromatin remodelers that govern the cellular machinery's access to DNA, thereby controlling fundamental processes, including transcription, proliferation, and DNA damage repair. This review highlights what is currently known about how genetic and epigenetic perturbation of CHD proteins and the pathways that they regulate set the stage for cancer, providing new insight for designing more effective anti-cancer therapies.
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Affiliation(s)
- Alea A Mills
- Cold Spring Harbor Laboratory, Cold Spring Harbor, New York, 11724
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11
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Inhaled Pollutants: The Molecular Scene behind Respiratory and Systemic Diseases Associated with Ultrafine Particulate Matter. Int J Mol Sci 2017; 18:ijms18020243. [PMID: 28125025 PMCID: PMC5343780 DOI: 10.3390/ijms18020243] [Citation(s) in RCA: 104] [Impact Index Per Article: 14.9] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2016] [Revised: 01/09/2017] [Accepted: 01/13/2017] [Indexed: 01/10/2023] Open
Abstract
Air pollution of anthropogenic origin is largely from the combustion of biomass (e.g., wood), fossil fuels (e.g., cars and trucks), incinerators, landfills, agricultural activities and tobacco smoke. Air pollution is a complex mixture that varies in space and time, and contains hundreds of compounds including volatile organic compounds (e.g., benzene), metals, sulphur and nitrogen oxides, ozone and particulate matter (PM). PM0.1 (ultrafine particles (UFP)), those particles with a diameter less than 100 nm (includes nanoparticles (NP)) are considered especially dangerous to human health and may contribute significantly to the development of numerous respiratory and cardiovascular diseases such as chronic obstructive pulmonary disease (COPD) and atherosclerosis. Some of the pathogenic mechanisms through which PM0.1 may contribute to chronic disease is their ability to induce inflammation, oxidative stress and cell death by molecular mechanisms that include transcription factors such as nuclear factor κB (NF-κB) and nuclear factor (erythroid-derived 2)-like 2 (Nrf2). Epigenetic mechanisms including non-coding RNA (ncRNA) may also contribute towards the development of chronic disease associated with exposure to PM0.1. This paper highlights emerging molecular concepts associated with inhalational exposure to PM0.1 and their ability to contribute to chronic respiratory and systemic disease.
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Sundar IK, Rahman I. Gene expression profiling of epigenetic chromatin modification enzymes and histone marks by cigarette smoke: implications for COPD and lung cancer. Am J Physiol Lung Cell Mol Physiol 2016; 311:L1245-L1258. [PMID: 27793800 DOI: 10.1152/ajplung.00253.2016] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2016] [Accepted: 10/23/2016] [Indexed: 01/23/2023] Open
Abstract
Chromatin-modifying enzymes mediate DNA methylation and histone modifications on recruitment to specific target gene loci in response to various stimuli. The key enzymes that regulate chromatin accessibility for maintenance of modifications in DNA and histones, and for modulation of gene expression patterns in response to cigarette smoke (CS), are not known. We hypothesize that CS exposure alters the gene expression patterns of chromatin-modifying enzymes, which then affects multiple downstream pathways involved in the response to CS. We have, therefore, analyzed chromatin-modifying enzyme profiles and validated by quantitative real-time PCR (qPCR). We also performed immunoblot analysis of targeted histone marks in C57BL/6J mice exposed to acute and subchronic CS, and of lungs from nonsmokers, smokers, and patients with chronic obstructive pulmonary disease (COPD). We found a significant increase in expression of several chromatin modification enzymes, including DNA methyltransferases, histone acetyltransferases, histone methyltransferases, and SET domain proteins, histone kinases, and ubiquitinases. Our qPCR validation data revealed a significant downregulation of Dnmt1, Dnmt3a, Dnmt3b, Hdac2, Hdac4, Hat1, Prmt1, and Aurkb We identified targeted chromatin histone marks (H3K56ac and H4K12ac), which are induced by CS. Thus CS-induced genotoxic stress differentially affects the expression of epigenetic modulators that regulate transcription of target genes via DNA methylation and site-specific histone modifications. This may have implications in devising epigenetic-based therapies for COPD and lung cancer.
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Affiliation(s)
- Isaac K Sundar
- Department of Environmental Medicine, University of Rochester Medical Center, Rochester, New York
| | - Irfan Rahman
- Department of Environmental Medicine, University of Rochester Medical Center, Rochester, New York
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Bjaanæs MM, Fleischer T, Halvorsen AR, Daunay A, Busato F, Solberg S, Jørgensen L, Kure E, Edvardsen H, Børresen-Dale AL, Brustugun OT, Tost J, Kristensen V, Helland Å. Genome-wide DNA methylation analyses in lung adenocarcinomas: Association with EGFR, KRAS and TP53 mutation status, gene expression and prognosis. Mol Oncol 2016; 10:330-43. [PMID: 26601720 PMCID: PMC5528958 DOI: 10.1016/j.molonc.2015.10.021] [Citation(s) in RCA: 57] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2015] [Revised: 09/25/2015] [Accepted: 10/28/2015] [Indexed: 01/29/2023] Open
Abstract
BACKGROUND DNA methylation alterations are early events in tumorigenesis and important in the regulation of gene expression in cancer cells. Lung cancer patients have in general a poor prognosis, and a deeper insight into the epigenetic landscape in lung adenocarcinoma tumors and its prognostic implications is needed. RESULTS We determined whole-genome DNA methylation profiles of 164 fresh frozen lung adenocarcinoma samples and 19 samples of matched normal lung tissue using the Illumina Infinium 450K array. A large number of differentially methylated CpGs in lung adenocarcinoma tissue were identified, and specific methylation profiles were observed in tumors with mutations in the EGFR-, KRAS- or TP53 genes and according to the patients' smoking status. The methylation levels were correlated with gene expression and both positive and negative correlations were seen. Methylation profiles of the tumor samples identified subtypes of tumors with distinct prognosis, including one subtype enriched for TP53 mutant tumors. A prognostic index based on the methylation levels of 33 CpGs was established, and was significantly associated with prognosis in the univariate analysis using an independent cohort of lung adenocarcinoma patients from The Cancer Genome Atlas project. CpGs in the HOX B and HOX C gene clusters were represented in the prognostic signature. CONCLUSIONS Methylation differences mirror biologically important features in the etiology of lung adenocarcinomas and influence prognosis.
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Affiliation(s)
- Maria Moksnes Bjaanæs
- Department of Genetics, Institute for Cancer Research, Oslo University Hospital - The Norwegian Radium Hospital, Oslo, Norway; Department of Oncology, Oslo University Hospital - The Norwegian Radium Hospital, Oslo, Norway.
| | - Thomas Fleischer
- Department of Genetics, Institute for Cancer Research, Oslo University Hospital - The Norwegian Radium Hospital, Oslo, Norway; The K.G. Jebsen Censtre for Breast Cancer Research, Institute for Clinical Medicine, Faculty of Medicine, University of Oslo, Norway.
| | - Ann Rita Halvorsen
- Department of Genetics, Institute for Cancer Research, Oslo University Hospital - The Norwegian Radium Hospital, Oslo, Norway.
| | - Antoine Daunay
- Laboratory for Functional Genomics, Fondation Jean Dausset - CEPH, 75010 Paris, France.
| | - Florence Busato
- Laboratory for Epigenetics and Environment (LEE), Centre National de Génotypage, CEA - Institut de Génomique, 91000 Evry, France.
| | - Steinar Solberg
- Department of Cardiothoracic Surgery, Oslo University Hospital-Rikshospitalet, Oslo, Norway.
| | - Lars Jørgensen
- Department of Cardiothoracic Surgery, Oslo University Hospital-Rikshospitalet, Oslo, Norway.
| | - Elin Kure
- Department of Genetics, Institute for Cancer Research, Oslo University Hospital - The Norwegian Radium Hospital, Oslo, Norway.
| | - Hege Edvardsen
- Department of Genetics, Institute for Cancer Research, Oslo University Hospital - The Norwegian Radium Hospital, Oslo, Norway.
| | - Anne-Lise Børresen-Dale
- Department of Genetics, Institute for Cancer Research, Oslo University Hospital - The Norwegian Radium Hospital, Oslo, Norway; Institute of Clinical Medicine, Faculty of Medicine, University of Oslo, Norway.
| | - Odd Terje Brustugun
- Department of Genetics, Institute for Cancer Research, Oslo University Hospital - The Norwegian Radium Hospital, Oslo, Norway; Department of Oncology, Oslo University Hospital - The Norwegian Radium Hospital, Oslo, Norway.
| | - Jörg Tost
- Laboratory for Epigenetics and Environment (LEE), Centre National de Génotypage, CEA - Institut de Génomique, 91000 Evry, France.
| | - Vessela Kristensen
- Department of Genetics, Institute for Cancer Research, Oslo University Hospital - The Norwegian Radium Hospital, Oslo, Norway; The K.G. Jebsen Censtre for Breast Cancer Research, Institute for Clinical Medicine, Faculty of Medicine, University of Oslo, Norway; Department of Clinical Molecular Biology and Laboratory Science (EpiGen), Division of Medicine, Akershus University Hospital, Lørenskog, Norway.
| | - Åslaug Helland
- Department of Genetics, Institute for Cancer Research, Oslo University Hospital - The Norwegian Radium Hospital, Oslo, Norway; Department of Oncology, Oslo University Hospital - The Norwegian Radium Hospital, Oslo, Norway.
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Lee ST, Wiemels JL. Genome-wide CpG island methylation and intergenic demethylation propensities vary among different tumor sites. Nucleic Acids Res 2015; 44:1105-17. [PMID: 26464434 PMCID: PMC4756811 DOI: 10.1093/nar/gkv1038] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2015] [Accepted: 09/30/2015] [Indexed: 12/20/2022] Open
Abstract
The epigenetic landscape of cancer includes both focal hypermethylation and broader hypomethylation in a genome-wide manner. By means of a comprehensive genomic analysis on 6637 tissues of 21 tumor types, we here show that the degrees of overall methylation in CpG island (CGI) and demethylation in intergenic regions, defined as ‘backbone’, largely vary among different tumors. Depending on tumor type, both CGI methylation and backbone demethylation are often associated with clinical, epidemiological and biological features such as age, sex, smoking history, anatomic location, histological type and grade, stage, molecular subtype and biological pathways. We found connections between CGI methylation and hypermutability, microsatellite instability, IDH1 mutation, 19p gain and polycomb features, and backbone demethylation with chromosomal instability, NSD1 and TP53 mutations, 5q and 19p loss and long repressive domains. These broad epigenetic patterns add a new dimension to our understanding of tumor biology and its clinical implications.
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Affiliation(s)
- Seung-Tae Lee
- Department of Laboratory Medicine, Yonsei University College of Medicine, Seoul, 120752, Republic of Korea
| | - Joseph L Wiemels
- Department of Epidemiology and Biostatistics, University of California, San Francisco, San Francisco, California, CA 94158, USA
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15
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Brown AN, Vied C, Dennis JH, Bhide PG. Nucleosome Repositioning: A Novel Mechanism for Nicotine- and Cocaine-Induced Epigenetic Changes. PLoS One 2015; 10:e0139103. [PMID: 26414157 PMCID: PMC4586372 DOI: 10.1371/journal.pone.0139103] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2014] [Accepted: 09/09/2015] [Indexed: 11/19/2022] Open
Abstract
Drugs of abuse modify behavior by altering gene expression in the brain. Gene expression can be regulated by changes in DNA methylation as well as by histone modifications, which alter chromatin structure, DNA compaction and DNA accessibility. In order to better understand the molecular mechanisms directing drug-induced changes in chromatin structure, we examined DNA-nucleosome interactions within promoter regions of 858 genes in human neuroblastoma cells (SH-SY5Y) exposed to nicotine or cocaine. Widespread, drug- and time-resolved repositioning of nucleosomes was identified at the transcription start site and promoter region of multiple genes. Nicotine and cocaine produced unique and shared changes in terms of the numbers and types of genes affected, as well as repositioning of nucleosomes at sites which could increase or decrease the probability of gene expression based on DNA accessibility. Half of the drug-induced nucleosome positions approximated a theoretical model of nucleosome occupancy based on physical and chemical characteristics of the DNA sequence, whereas the basal or drug naïve positions were generally DNA sequence independent. Thus we suggest that nucleosome repositioning represents an initial dynamic genome-wide alteration of the transcriptional landscape preceding more selective downstream transcriptional reprogramming, which ultimately characterizes the cell- and tissue-specific responses to drugs of abuse.
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Affiliation(s)
- Amber N. Brown
- Center for Brain Repair, Department of Biomedical Sciences, Florida State University College of Medicine, Tallahassee, FL, United States of America
| | - Cynthia Vied
- Center for Brain Repair, Department of Biomedical Sciences, Florida State University College of Medicine, Tallahassee, FL, United States of America
| | - Jonathan H. Dennis
- Department of Biological Sciences, Florida State University, Tallahassee, Florida, United States of America
| | - Pradeep G. Bhide
- Center for Brain Repair, Department of Biomedical Sciences, Florida State University College of Medicine, Tallahassee, FL, United States of America
- * E-mail:
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Zhang S, Zhou M, Jiang G, Gong C, Cui D, Luo L, Wu D, Huang H, Zhang Q, Yang L. Expression and DNA methylation status of the Rap2B gene in human bronchial epithelial cells treated by cigarette smoke condensate. Inhal Toxicol 2015; 27:502-9. [PMID: 26308105 DOI: 10.3109/08958378.2015.1076546] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
BACKGROUND The relationship between lung cancer and smoking has been demonstrated. The Rap2B gene is usually overexpressed in lung cancers. This study was aimed to investigate the Rap2B gene expression and its promoter methylation in human bronchial epithelial cells (16HBE) treated by cigarette smoke condensate (CSC). METHODS 16HBE cells were treated with CSC (1/8 IC50). Soft ager assay, tumorigenicity test, chromosome aberrations analysis were used to identify the transformed cells. The expression level of mRNA and protein of Rap2B was detected using real time PCR and Western blotting, respectively. The genome DNA methylation level was detected using combined bisulfite restriction analysis (COBRA) and the methylation status of the target fragment in Rap2B gene promoter was determined by bisulfite sequencing PCR (BSP). RESULTS The 16HBE cells were successfully malignant transformed after the chronic exposure to CSC. The expression of Rap2B gradually increased in the process of malignant transformation. Meanwhile, global DNA was hypomethylated. However, no obvious change was observed in the methylation level of Rap2B gene promoter in transformed 16HBE cells. CONCLUSIONS Rap2B gene may play an important role in the process of lung cancer and global DNA hypomethylation might be an early event in tumorigenesis.
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Affiliation(s)
- Shuangling Zhang
- a School of Public Health, Medical College, Wuhan University of Science and Technology , Wuhan , China
| | - Ming Zhou
- b Public Health College of Zhengzhou University , Zhengzhou , China
- c Changsha Center of Supervision & Inspection on Food Quality Safety , Changsha , China
| | - Gaofeng Jiang
- a School of Public Health, Medical College, Wuhan University of Science and Technology , Wuhan , China
| | - Chunmei Gong
- d Shenzhen Center for Chronic Disease Control and Prevention , Shenzhen , China , and
| | - Dong Cui
- e Shenzhen Center for Disease Control and Prevention , Shenzhen , China
| | - Lingfeng Luo
- e Shenzhen Center for Disease Control and Prevention , Shenzhen , China
| | - Desheng Wu
- e Shenzhen Center for Disease Control and Prevention , Shenzhen , China
| | - Haiyan Huang
- e Shenzhen Center for Disease Control and Prevention , Shenzhen , China
| | - Qiao Zhang
- b Public Health College of Zhengzhou University , Zhengzhou , China
| | - Linqing Yang
- e Shenzhen Center for Disease Control and Prevention , Shenzhen , China
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Bernstein C, Bernstein H. Epigenetic reduction of DNA repair in progression to gastrointestinal cancer. World J Gastrointest Oncol 2015; 7:30-46. [PMID: 25987950 PMCID: PMC4434036 DOI: 10.4251/wjgo.v7.i5.30] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/14/2014] [Revised: 03/18/2015] [Accepted: 04/20/2015] [Indexed: 02/05/2023] Open
Abstract
Deficiencies in DNA repair due to inherited germ-line mutations in DNA repair genes cause increased risk of gastrointestinal (GI) cancer. In sporadic GI cancers, mutations in DNA repair genes are relatively rare. However, epigenetic alterations that reduce expression of DNA repair genes are frequent in sporadic GI cancers. These epigenetic reductions are also found in field defects that give rise to cancers. Reduced DNA repair likely allows excessive DNA damages to accumulate in somatic cells. Then either inaccurate translesion synthesis past the un-repaired DNA damages or error-prone DNA repair can cause mutations. Erroneous DNA repair can also cause epigenetic alterations (i.e., epimutations, transmitted through multiple replication cycles). Some of these mutations and epimutations may cause progression to cancer. Thus, deficient or absent DNA repair is likely an important underlying cause of cancer. Whole genome sequencing of GI cancers show that between thousands to hundreds of thousands of mutations occur in these cancers. Epimutations that reduce DNA repair gene expression and occur early in progression to GI cancers are a likely source of this high genomic instability. Cancer cells deficient in DNA repair are more vulnerable than normal cells to inactivation by DNA damaging agents. Thus, some of the most clinically effective chemotherapeutic agents in cancer treatment are DNA damaging agents, and their effectiveness often depends on deficient DNA repair in cancer cells. Recently, at least 18 DNA repair proteins, each active in one of six DNA repair pathways, were found to be subject to epigenetic reduction of expression in GI cancers. Different DNA repair pathways repair different types of DNA damage. Evaluation of which DNA repair pathway(s) are deficient in particular types of GI cancer and/or particular patients may prove useful in guiding choice of therapeutic agents in cancer therapy.
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18
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Yang M, Chen P, Peng H, Zhang H, Chen Y, Cai S, Lu Q, Guan C. Cigarette smoke extract induces aberrant cytochrome-c oxidase subunit II methylation and apoptosis in human umbilical vascular endothelial cells. Am J Physiol Cell Physiol 2015; 308:C378-84. [PMID: 25500741 DOI: 10.1152/ajpcell.00197.2014] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Cigarette smoke-induced apoptosis of vascular endothelial cells contributes to the pathogenesis of chronic obstructive pulmonary disease. However, the mechanisms responsible for endothelial apoptosis remain poorly understood. We conducted an in vitro study to investigate whether DNA methylation is involved in smoking-induced endothelial apoptosis. Human umbilical vascular endothelial cells (HUVECs) were exposed to cigarette smoke extract (CSE) at a range of concentrations (0-10%). HUVECs were also incubated with a demethylating reagent, 5-aza-2'-deoxycytidinem (AZA), with and without CSE. Apoptosis was assessed by terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling assay and flow cytometry using annexin V-FITC/propidium iodide staining. We found that CSE treatment significantly increased HUVEC apoptosis in a dose- and time-dependent manner. Quantitative real-time RT-PCR and immunoblot revealed that CSE treatment decreased cytochrome-c oxidase subunit II (COX II) mRNA and protein levels and decreased COX activity. Methylation-specific PCR and direct bisulfite sequencing revealed positive COX II gene methylation. AZA administration partly increased mRNA and protein expressions of COX II, and COX activity decreased by CSE and attenuated the toxic effects of CSE. Our results showed that CSE induced aberrant COX II methylation and apoptosis in HUVECs.
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Affiliation(s)
- Min Yang
- Department of Respiratory Medicine, The Second Xiangya Hospital of Central-South University, Hunan, Changsha, China
| | - Ping Chen
- Department of Respiratory Medicine, The Second Xiangya Hospital of Central-South University, Hunan, Changsha, China;
| | - Hong Peng
- Department of Respiratory Medicine, The Second Xiangya Hospital of Central-South University, Hunan, Changsha, China
| | - Hongliang Zhang
- Emergency Department, The Second Xiangya Hospital of Central-South University, Hunan, Changsha, China
| | - Yan Chen
- Department of Respiratory Medicine, The Second Xiangya Hospital of Central-South University, Hunan, Changsha, China
| | - Shan Cai
- Department of Respiratory Medicine, The Second Xiangya Hospital of Central-South University, Hunan, Changsha, China
| | - Qianjin Lu
- Dermatological Department, The Second Xiangya Hospital of Central-South University, Hunan, Changsha, China
| | - Chaxiang Guan
- Department of Physiology, Central-South University, Hunan, Changsha, China
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