1
|
Shao D, Liu C, Wang Y, Lin J, Cheng X, Han P, Li Z, Jian D, Nie J, Jiang M, Wei Y, Xing J, Guo Z, Wang W, Yi X, Tang H. DNMT1 determines osteosarcoma cell resistance to apoptosis by associatively modulating DNA and mRNA cytosine-5 methylation. FASEB J 2023; 37:e23284. [PMID: 37905981 DOI: 10.1096/fj.202301306r] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2023] [Revised: 09/17/2023] [Accepted: 10/17/2023] [Indexed: 11/02/2023]
Abstract
Cellular apoptosis is a central mechanism leveraged by chemotherapy to treat human cancers. 5-Methylcytosine (m5C) modifications installed on both DNA and mRNA are documented to regulate apoptosis independently. However, the interplay or crosstalk between them in cellular apoptosis has not yet been explored. Here, we reported that promoter methylation by DNMT1 coordinated with mRNA methylation by NSun2 to regulate osteosarcoma cell apoptosis. DNMT1 was induced during osteosarcoma cell apoptosis triggered by chemotherapeutic drugs, whereas NSun2 expression was suppressed. DNMT1 was found to repress NSun2 expression by methylating the NSun2 promoter. Moreover, DNMT1 and NSun2 regulate the anti-apoptotic genes AXL, NOTCH2, and YAP1 through DNA and mRNA methylation, respectively. Upon exposure to cisplatin or doxorubicin, DNMT1 elevation drastically reduced the expression of these anti-apoptotic genes via enhanced promoter methylation coupled with NSun2 ablation-mediated attenuation of mRNA methylation, thus rendering osteosarcoma cells to apoptosis. Collectively, our findings establish crosstalk of importance between DNA and RNA cytosine methylations in determining osteosarcoma resistance to apoptosis during chemotherapy, shedding new light on future treatment of osteosarcoma, and adding additional layers to the control of gene expression at different epigenetic levels.
Collapse
Affiliation(s)
- Dongxing Shao
- Department of Biochemistry and Molecular Biology, Beijing Key Laboratory of Protein Posttranslational Modifications and Cell Function, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, China
- National Health Commission Key Laboratory of Cardiovascular Regenerative Medicine, Heart Center of Henan Provincial People's Hospital, Central China Fuwai Hospital of Zhengzhou University, Fuwai Central China Cardiovascular Hospital & Central China Branch of National Center for Cardiovascular Diseases, Zhengzhou, China
| | - Cihang Liu
- Department of Biochemistry and Molecular Biology, Beijing Key Laboratory of Protein Posttranslational Modifications and Cell Function, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, China
- National Health Commission Key Laboratory of Cardiovascular Regenerative Medicine, Heart Center of Henan Provincial People's Hospital, Central China Fuwai Hospital of Zhengzhou University, Fuwai Central China Cardiovascular Hospital & Central China Branch of National Center for Cardiovascular Diseases, Zhengzhou, China
| | - Yingying Wang
- National Health Commission Key Laboratory of Cardiovascular Regenerative Medicine, Heart Center of Henan Provincial People's Hospital, Central China Fuwai Hospital of Zhengzhou University, Fuwai Central China Cardiovascular Hospital & Central China Branch of National Center for Cardiovascular Diseases, Zhengzhou, China
| | - Jing Lin
- Department of Laboratory Medicine, the Fourth Medical Center, Chinese PLA General Hospital, Beijing, China
| | - Xiaolei Cheng
- Department of Anesthesiology, Affiliated Drum Tower Hospital of Medical School of Nanjing University, Nanjing, China
| | - Pei Han
- Department of Biochemistry and Molecular Biology, Beijing Key Laboratory of Protein Posttranslational Modifications and Cell Function, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, China
| | - Zhen Li
- National Health Commission Key Laboratory of Cardiovascular Regenerative Medicine, Heart Center of Henan Provincial People's Hospital, Central China Fuwai Hospital of Zhengzhou University, Fuwai Central China Cardiovascular Hospital & Central China Branch of National Center for Cardiovascular Diseases, Zhengzhou, China
| | - Dongdong Jian
- Department of Biochemistry and Molecular Biology, Beijing Key Laboratory of Protein Posttranslational Modifications and Cell Function, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, China
| | - Junwei Nie
- R&D Department, Vazyme Biotech Co., Ltd, Nanjing, China
| | | | - Yuanzhi Wei
- R&D Department, Vazyme Biotech Co., Ltd, Nanjing, China
| | - Junyue Xing
- National Health Commission Key Laboratory of Cardiovascular Regenerative Medicine, Heart Center of Henan Provincial People's Hospital, Central China Fuwai Hospital of Zhengzhou University, Fuwai Central China Cardiovascular Hospital & Central China Branch of National Center for Cardiovascular Diseases, Zhengzhou, China
- Henan Key Laboratory of Chronic Disease Management, Department of Health Management Center, Henan Provincial People's Hospital, Department of Health Management Center of Central China Fuwai Hospital, Central China Fuwai Hospital of Zhengzhou University, Zhengzhou, China
| | - Zhiping Guo
- National Health Commission Key Laboratory of Cardiovascular Regenerative Medicine, Heart Center of Henan Provincial People's Hospital, Central China Fuwai Hospital of Zhengzhou University, Fuwai Central China Cardiovascular Hospital & Central China Branch of National Center for Cardiovascular Diseases, Zhengzhou, China
- Henan Key Laboratory of Chronic Disease Management, Department of Health Management Center, Henan Provincial People's Hospital, Department of Health Management Center of Central China Fuwai Hospital, Central China Fuwai Hospital of Zhengzhou University, Zhengzhou, China
| | - Wengong Wang
- Department of Biochemistry and Molecular Biology, Beijing Key Laboratory of Protein Posttranslational Modifications and Cell Function, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, China
| | - Xia Yi
- Department of Biochemistry and Molecular Biology, Beijing Key Laboratory of Protein Posttranslational Modifications and Cell Function, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, China
| | - Hao Tang
- National Health Commission Key Laboratory of Cardiovascular Regenerative Medicine, Heart Center of Henan Provincial People's Hospital, Central China Fuwai Hospital of Zhengzhou University, Fuwai Central China Cardiovascular Hospital & Central China Branch of National Center for Cardiovascular Diseases, Zhengzhou, China
- Henan Key Laboratory of Chronic Disease Management, Department of Health Management Center, Henan Provincial People's Hospital, Department of Health Management Center of Central China Fuwai Hospital, Central China Fuwai Hospital of Zhengzhou University, Zhengzhou, China
| |
Collapse
|
2
|
Duan L, Tadi MJ, Maki CG. CSE1L is a negative regulator of the RB-DREAM pathway in p53 wild-type NSCLC and can be targeted using an HDAC1/2 inhibitor. Sci Rep 2023; 13:16271. [PMID: 37759078 PMCID: PMC10533896 DOI: 10.1038/s41598-023-43218-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2023] [Accepted: 09/21/2023] [Indexed: 09/29/2023] Open
Abstract
P53 represses transcription by activating p21 expression and promoting formation of RB1-E2F1 and RBL1/RBL2-DREAM transcription repressor complexes. The DREAM complex is composed of DP1, RB-family proteins RBL1 or RBL2 (p107/p130), E2F4/5, and MuvB. We recently reported RBL2-DREAM contributes to improved therapy responses in p53 wild-type NSCLC cells and improved outcomes in NSCLC patients whose tumors express wild-type p53. In the current study we identified CSE1L as a novel inhibitor of the RBL2-DREAM pathway and target to activate RBL2-DREAM in NSCLC cells. CSE1L is an oncoprotein that maintains repression of genes that can be reactivated by HDAC inhibitors. Mocetinostat is a HDAC inhibitor in clinical trials with selectivity against HDACs 1 and 2. Knockdown of CSE1L in NSCLC cells or treatment with mocetinostat increased p21, activated RB1 and RBL2, repressed DREAM target genes, and induced toxicity in a manner that required wild-type p53. Lastly, we found high levels of CSE1L and specific DREAM-target genes are candidate markers to identify p53 wild-type NSCLCs most responsive to mocetinostat. Thus, we identified CSE1L as a critical negative regulator of the RB-DREAM pathway in p53 wild-type NSCLC that can be indirectly targeted with HDAC1/2 inhibitors (mocetinostat) in current clinical trials. High expression of CSE1L and DREAM target genes could serve as a biomarker to identify p53 wild-type NSCLCs most responsive to this HDAC1/2 inhibitor.
Collapse
Affiliation(s)
- Lei Duan
- Department of Anatomy and Cell Biology, Rush University Medical Center, 600 S. Paulina Street, AcFac 507, Chicago, IL, 60612, USA
| | - Mehrdad Jafari Tadi
- Department of Anatomy and Cell Biology, Rush University Medical Center, 600 S. Paulina Street, AcFac 507, Chicago, IL, 60612, USA
| | - Carl G Maki
- Department of Anatomy and Cell Biology, Rush University Medical Center, 600 S. Paulina Street, AcFac 507, Chicago, IL, 60612, USA.
| |
Collapse
|
3
|
Sapozhnikov DM, Szyf M. Enzyme-free targeted DNA demethylation using CRISPR-dCas9-based steric hindrance to identify DNA methylation marks causal to altered gene expression. Nat Protoc 2022; 17:2840-2881. [PMID: 36207463 DOI: 10.1038/s41596-022-00741-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2022] [Accepted: 06/22/2022] [Indexed: 11/09/2022]
Abstract
DNA methylation involves the enzymatic addition of a methyl group primarily to cytosine residues in DNA. This protocol describes how to produce complete and minimally confounded DNA demethylation of specific sites in the genome of cultured cells by clustered regularly interspaced short palindromic repeats (CRISPR)-dCas9 and without the involvement of an epigenetic-modifying enzyme, the purpose of which is the evaluation of the functional (i.e., gene expression or phenotypic) consequences of DNA demethylation of specific sites that have been previously implicated in particular pathological or physiological contexts. This protocol maximizes the ability of the easily reprogrammable CRISPR-dCas9 system to assess the impact of DNA methylation from a causal rather than correlational perspective: alternative protocols for CRISPR-dCas9-based site-specific DNA methylation or demethylation rely on the recruitment of epigenetic enzymes that exhibit additional nonspecific activities at both the targeted site and throughout the genome, confounding conclusions of causality of DNA methylation. Inhibition or loss of DNA methylation is accomplished by three consecutive lentiviral transductions. The first two lentiviruses establish stable expression of dCas9 and a guide RNA, which will physically obstruct either maintenance or de novo DNA methyltransferase activity at the guide RNA target site. A third lentivirus introduces Cre recombinase to delete the dCas9 transgene, which leads to loss of dCas9 from the target site, allowing transcription factors and/or the transcription machinery to interact with the demethylated target site. This protocol requires 3-8 months to complete owing to prolonged cell passaging times, but there is little hands-on time, and no specific skills beyond basic molecular biology techniques are necessary.
Collapse
Affiliation(s)
- Daniel M Sapozhnikov
- Department of Pharmacology and Therapeutics, Faculty of Medicine, McGill University, Montreal, Quebec, Canada
| | - Moshe Szyf
- Department of Pharmacology and Therapeutics, Faculty of Medicine, McGill University, Montreal, Quebec, Canada.
| |
Collapse
|
4
|
Xiong M, Pan B, Wang X, Nie J, Pan Y, Sun H, Xu T, Cho WCS, Wang S, He B. Susceptibility of Genetic Variations in Methylation Pathway to Gastric Cancer. Pharmgenomics Pers Med 2022; 15:441-448. [PMID: 35548064 PMCID: PMC9081620 DOI: 10.2147/pgpm.s340941] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2021] [Accepted: 02/17/2022] [Indexed: 12/04/2022] Open
Abstract
Background DNA methylation in the CpG island is associated with gastric cancer, genetic variations residue in genes involved in methylation pathway could contribute to the occurrence of gastric cancer. Here, we investigated the association between DNMTs (DNMT1/DNMT3A/DNMT3B), MTHFR genetic variations and gastric cancer risk and patients' survival. Patients and Methods We recruited 490 gastric cancer patients and 488 age- and sex-matched healthy controls. The genotypes of the genetic variations were detected by a Mass-array platform. A commercial Helicobacter pylori (H. pylori) immunogold testing kit was used to determine the H. pylori infection. Results We found that carriers of DNMT1 rs2228612C allele was associated with decreased gastric cancer risk (CT vs. TT: adjusted OR = 0.70, 95% CI = 0.53-0.94, P = 0.02; CT/CC vs.TT: adjusted OR = 0.73, 95% CI = 0.56-0.96, P = 0.02). Further stratified analysis showed that DNMT1 rs2228612 CT/CC were associated with a decreased gastric cancer risk in the subgroups of age ≤64 years old (adjusted OR = 0.61, 95% CI = 0.41-0.90, P = 0.01), male (adjusted OR = 0.72, 95% CI = 0.53-0.98, P = 0.03), negative H. pylori infection (adjusted OR = 0.67, 95% CI = 0.45-0.98, P = 0.04), tumor stage T3-T4 (adjusted OR = 0.69, 95% CI = 0.51-0.92, P = 0.01), and non-gastric cardiac adenocarcinoma (NGCA) (adjusted OR = 0.72, 95% CI = 0.54-0.97, P = 0.03). However, none of the genetic variations of this study was associated with overall survival. Conclusion We concluded that the DNMT1 rs2228612C genotype is a protective factor for gastric cancer in Han Chinese population.
Collapse
Affiliation(s)
- Mengqiu Xiong
- Clinical Laboratory, Nanjing First Hospital, Nanjing Medical University, Nanjing, 210006, People’s Republic of China
| | - Bei Pan
- Medical College, Southeast University, Nanjing, 210006, People’s Republic of China
| | - Xuhong Wang
- Medical College, Southeast University, Nanjing, 210006, People’s Republic of China
| | - Junjie Nie
- Clinical Laboratory, Nanjing First Hospital, Nanjing Medical University, Nanjing, 210006, People’s Republic of China
| | - Yuqin Pan
- Clinical Laboratory, Nanjing First Hospital, Nanjing Medical University, Nanjing, 210006, People’s Republic of China
| | - Huiling Sun
- Clinical Laboratory, Nanjing First Hospital, Nanjing Medical University, Nanjing, 210006, People’s Republic of China
| | - Tao Xu
- Clinical Laboratory, Nanjing First Hospital, Nanjing Medical University, Nanjing, 210006, People’s Republic of China
| | - William C S Cho
- Department of Clinical Oncology, Queen Elizabeth Hospital, Hongkong SAR, People’s Republic of China
| | - Shukui Wang
- Clinical Laboratory, Nanjing First Hospital, Nanjing Medical University, Nanjing, 210006, People’s Republic of China
- Collaborative Innovation Center for Cancer Personalized Medicine, Nanjing Medical University, Nanjing, 211166, People’s Republic of China
- Helicobacter pylori Research Key Laboratory, Nanjing Medical University, Nanjing, 211166, People’s Republic of China
| | - Bangshun He
- Clinical Laboratory, Nanjing First Hospital, Nanjing Medical University, Nanjing, 210006, People’s Republic of China
- Collaborative Innovation Center for Cancer Personalized Medicine, Nanjing Medical University, Nanjing, 211166, People’s Republic of China
- Helicobacter pylori Research Key Laboratory, Nanjing Medical University, Nanjing, 211166, People’s Republic of China
| |
Collapse
|
5
|
Cristalli C, Manara MC, Valente S, Pellegrini E, Bavelloni A, De Feo A, Blalock W, Di Bello E, Piñeyro D, Merkel A, Esteller M, Tirado OM, Mai A, Scotlandi K. Novel Targeting of DNA Methyltransferase Activity Inhibits Ewing Sarcoma Cell Proliferation and Enhances Tumor Cell Sensitivity to DNA Damaging Drugs by Activating the DNA Damage Response. Front Endocrinol (Lausanne) 2022; 13:876602. [PMID: 35712255 PMCID: PMC9197596 DOI: 10.3389/fendo.2022.876602] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Accepted: 04/19/2022] [Indexed: 12/02/2022] Open
Abstract
DNA methylation is an important component of the epigenetic machinery that regulates the malignancy of Ewing sarcoma (EWS), the second most common primary bone tumor in children and adolescents. Coordination of DNA methylation and DNA replication is critical for maintaining epigenetic programming and the DNMT1 enzyme has been demonstrated to have an important role in both maintaining the epigenome and controlling cell cycle. Here, we showed that the novel nonnucleoside DNMT inhibitor (DNMTi) MC3343 induces a specific depletion of DNMT1 and affects EWS tumor proliferation through a mechanism that is independent on DNA methylation. Depletion of DNMT1 causes perturbation of the cell cycle, with an accumulation of cells in the G1 phase, and DNA damage, as revealed by the induction of γH2AX foci. These effects elicited activation of p53-dependent signaling and apoptosis in p53wt cells, while in p53 mutated cells, persistent micronuclei and increased DNA instability was observed. Treatment with MC3343 potentiates the efficacy of DNA damaging agents such as doxorubicin and PARP-inhibitors (PARPi). This effect correlates with increased DNA damage and synergistic tumor cytotoxicity, supporting the use of the DNMTi MC3343 as an adjuvant agent in treating EWS.
Collapse
Affiliation(s)
- Camilla Cristalli
- Laboratory of Experimental Oncology, IRCCS Istituto Ortopedico Rizzoli, Bologna, Italy
- *Correspondence: Camilla Cristalli, ; Katia Scotlandi,
| | - Maria Cristina Manara
- Laboratory of Experimental Oncology, IRCCS Istituto Ortopedico Rizzoli, Bologna, Italy
| | - Sergio Valente
- Department of Drug Chemistry and Technologies, Faculty of Pharmacy and Medicine, Sapienza University of Rome, Rome, Italy
| | - Evelin Pellegrini
- Laboratory of Experimental Oncology, IRCCS Istituto Ortopedico Rizzoli, Bologna, Italy
| | - Alberto Bavelloni
- Laboratory of Experimental Oncology, IRCCS Istituto Ortopedico Rizzoli, Bologna, Italy
| | - Alessandra De Feo
- Laboratory of Experimental Oncology, IRCCS Istituto Ortopedico Rizzoli, Bologna, Italy
| | - William Blalock
- Istituto di Genetica Molecolare-Luigi Luca Cavalli Sforza, UOS Bologna, Consiglio Nazionale delle Ricerche (IGM-CNR), Bologna, Italy
| | - Elisabetta Di Bello
- Department of Drug Chemistry and Technologies, Faculty of Pharmacy and Medicine, Sapienza University of Rome, Rome, Italy
| | - David Piñeyro
- Josep Carreras Leukaemia Research Institute (IJC), Barcelona, Spain
| | - Angelika Merkel
- Josep Carreras Leukaemia Research Institute (IJC), Barcelona, Spain
| | - Manel Esteller
- Josep Carreras Leukaemia Research Institute (IJC), Barcelona, Spain
- Centro de Investigación Biomedica en Red Cancer (CIBERONC), Madrid, Spain
- Institució Catalana de Recerca i Estudis Avançats (ICREA), Barcelona, Spain
- Physiological Sciences Department, School of Medicine and Health Sciences, University of Barcelona (UB), Barcelona, Spain
| | - Oscar M. Tirado
- Sarcoma Research Group, Oncobell Program, Bellvitge Biomedical Research Institute (IDIBELL), Centro de Investigación Biomedica en Red Cancer (CIBERONC), Barcelona, Spain
| | - Antonello Mai
- Department of Drug Chemistry and Technologies, Faculty of Pharmacy and Medicine, Sapienza University of Rome, Rome, Italy
- Istituto Pasteur-Fondazione Cenci Bolognetti, Sapienza University of Rome, Rome, Italy
| | - Katia Scotlandi
- Laboratory of Experimental Oncology, IRCCS Istituto Ortopedico Rizzoli, Bologna, Italy
- *Correspondence: Camilla Cristalli, ; Katia Scotlandi,
| |
Collapse
|
6
|
Li B, He Y, Li P, Chen X. Leptin Receptor Overlapping Transcript (LEPROT) Is Associated with the Tumor Microenvironment and a Prognostic Predictor in Pan-Cancer. Front Genet 2021; 12:749435. [PMID: 34804118 PMCID: PMC8596502 DOI: 10.3389/fgene.2021.749435] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2021] [Accepted: 10/22/2021] [Indexed: 12/12/2022] Open
Abstract
Background Leptin receptor overlapping transcript (LEPROT) is reported to be involved in metabolism regulation and energy balance as well as molecular signaling of breast cancer and osteosarcoma. LEPROT is expressed in various tissue and is suggested to be involved in cancer developments but with contradictory roles. The comprehensive knowledge of the effects of LEPROT on cancer development and progression across pan-cancer is still missing. Methods The expressions of LEPROT in cancers were compared with corresponding normal tissues across pan-cancer types. The relationships between expression and methylation of LEPROT were then demonstrated. The correlations of LEPROT with the tumor microenvironment (TME), including immune checkpoints, tumor immune cells infiltration (TII), and cancer-associated fibroblasts (CAFs), were also investigated. Co-expression analyses and functional enrichments were conducted to suggest the most relevant genes and the mechanisms of the effects in cancers for LEPROT. Finally, the correlations of LEPROT with patient survival and immunotherapy response were explored. Results LEPROT expression was found to be significantly aberrant in 15/19 (78.9%) cancers compared with corresponding normal tissues; LEPROT was downregulated in 12 cancers and upregulated in three cancers. LEPROT expressions were overall negatively correlated with its methylation alterations. Moreover, LEPROT was profoundly correlated with the TME, including immune checkpoints, TIIs, and CAFs. According to co-expression analyses and functional enrichments, the interactions of LEPROT with the TME may be mediated by the interleukin six signal transducer/the Janus kinase/signal transducers and activators of the transcription signaling pathway. Prognostic values may exist for LEPROT to predict patient survival and immunotherapy response in a context-dependent way. Conclusions LEPROT affects cancer development by interfering with the TME and regulating inflammatory or immune signals. LEPROT may also serve as a potential prognostic marker or a target in cancer therapy. This is the first study to investigate the roles of LEPROT across pan-cancer.
Collapse
Affiliation(s)
- Bingsheng Li
- Department of Urology, Xiangya Hospital, Central South University, Changsha, China.,Department of Urology, University Hospital Munich, LMU Munich, Munich, Germany
| | - Yao He
- Department of Urology, Xiangya Hospital, Central South University, Changsha, China
| | - Pan Li
- Institute for Pathology of the Ludwig-Maximilians-Universität München, Munich, Germany
| | - Xiang Chen
- Department of Urology, Xiangya Hospital, Central South University, Changsha, China
| |
Collapse
|
7
|
Parker WB, Thottassery JV. 5-Aza-4'-thio-2'-deoxycytidine, a new orally bioavailable non-toxic "best-in-class" DNMT1 depleting agent in clinical development. J Pharmacol Exp Ther 2021; 379:211-222. [PMID: 34503994 DOI: 10.1124/jpet.121.000758] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2021] [Accepted: 09/01/2021] [Indexed: 11/22/2022] Open
Abstract
DNA methyltransferase 1 (DNMT1) is an enzyme that functions as a maintenance methyltransferase during DNA replication, and depletion of this enzyme from cells is considered to be a rational goal in DNA methylation dependent disorders. Two DNMT1 depleting agents aza-dCyd (5-aza-2'-deoxycytidine, decitabine) and aza-Cyd (5-aza-cytidine, azacitidine) are currently used for the treatment of myelodysplastic syndromes and acute myeloid leukemia, and have also been investigated for non-oncology indications such as sickle cell disease. However, these agents have several off-target activities leading to significant toxicities that limit dosing and duration of treatment. Development of more selective inhibitors of DNMT1 could therefore afford treatment for long durations at effective doses. We have discovered that 5-aza-4'-thio-2'-deoxycytidine (aza-T-dCyd) is as effective as aza-dCyd in depleting DNMT1 in mouse tumor models, but with markedly low toxicity. In this review we describe the preclinical studies that led to the development of aza-T-dCyd as a superior DNMT1 depleting agent with respect to aza-dCyd, and will describe its pharmacology, metabolism, and mechanism of action. In an effort to understand why aza-T-dCyd is a more selective DNMT1 depleting agent than aza-dCyd, we will also compare and contrast the activities of these two agents. Significance Statement Aza-T-dCyd is a potent DNMT1 depleting agent. Although similar in structure to decitabine (aza-dCyd) its metabolism and mechanism of action is different than that of aza-dCyd, resulting in less off target activity and less toxicity. The larger therapeutic index of aza-T-dCyd (DNMT1 depletion vs toxicity) in mice suggests that it would be a better clinical candidate to selectively deplete DNMT1 from target cells and determine whether or not depletion of DNMT1 is an effective target for various diseases.
Collapse
|
8
|
Jones R, Wijesinghe S, Wilson C, Halsall J, Liloglou T, Kanhere A. A long intergenic non-coding RNA regulates nuclear localization of DNA methyl transferase-1. iScience 2021; 24:102273. [PMID: 33851096 PMCID: PMC8022221 DOI: 10.1016/j.isci.2021.102273] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2020] [Revised: 12/21/2020] [Accepted: 03/02/2021] [Indexed: 01/10/2023] Open
Abstract
DNA methyl transferase-1 or DNMT1 maintains DNA methylation in the genome and is important for regulating gene expression in cells. Aberrant changes in DNMT1 activity and DNA methylation are commonly observed in cancers and many other diseases. Recently, a number of long intergenic non-protein-coding RNAs or lincRNAs have been shown to play a role in regulating DNMT1 activity. CCDC26 is a nuclear lincRNA that is frequently mutated in cancers and is a hotbed for disease-associated single nucleotide changes. However, the functional mechanism of CCDC26 is not understood. Here, we show that this lincRNA is concentrated on the nuclear periphery. Strikingly, in the absence of CCDC26 lincRNA, DNMT1 is mis-located in the cytoplasm, and the genomic DNA is significantly hypomethylated. This is accompanied by double-stranded DNA breaks and increased cell death. These results point to a previously unrecognized mechanism of lincRNA-mediated subcellular localization of DNMT1 and regulation of DNA methylation.
Collapse
Affiliation(s)
- Rhian Jones
- School of Biosciences, University of Birmingham, Edgbaston, Birmingham, UK
| | - Susanne Wijesinghe
- Institute of Inflammation and Ageing, University of Birmingham, Edgbaston, Birmingham, UK
| | - Claire Wilson
- Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Liverpool, UK
| | - John Halsall
- Institute of Genomic Sciences, University of Birmingham, Edgbaston, Birmingham, UK
| | - Triantafillos Liloglou
- Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Liverpool, UK
| | - Aditi Kanhere
- School of Biosciences, University of Birmingham, Edgbaston, Birmingham, UK.,Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Liverpool, UK
| |
Collapse
|
9
|
Patra SK. Roles of OCT4 in pathways of embryonic development and cancer progression. Mech Ageing Dev 2020; 189:111286. [PMID: 32531293 DOI: 10.1016/j.mad.2020.111286] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Revised: 04/08/2020] [Accepted: 06/06/2020] [Indexed: 12/11/2022]
Abstract
Somatic cells may be reprogrammed to pluripotent state by ectopic expression of certain transcription factors; namely, OCT4, SOX2, KLF4 and c-MYC. However, the molecular and cellular mechanisms are not adequately understood, especially for human embryonic development. Studies during the last five years implicated importance of OCT4 in human zygotic genome activation (ZGA), patterns of OCT4 protein folding and role of specialized sequences in binding to DNA for modulation of gene expression during development. Epigenetic modulation of OCT4 gene and post translational modifications of OCT4 protein activity in the context of multiple cancers are important issues. A consensus is emerging that chromatin organization and epigenetic landscape play crucial roles for the interactions of transcription factors, including OCT4 with the promoters and/or regulatory sequences of genes associated with human embryonic development (ZGA through lineage specification) and that when the epigenome niche is deregulated OCT4 helps in cancer progression, and how OCT4 silencing in somatic cells of adult organisms may impact ageing.
Collapse
Affiliation(s)
- Samir Kumar Patra
- Epigenetics and Cancer Research Laboratory, Biochemistry and Molecular Biology Group, Department of Life Science, National Institute of Technology, Rourkela, Odisha, 769008, India.
| |
Collapse
|
10
|
Sanaei M, Kavoosi F, Arabloo M. Effect of Curcumin in Comparison with Trichostatin A on the Reactivation of Estrogen Receptor Alpha gene Expression, Cell Growth Inhibition and Apoptosis Induction in Hepatocellular Carcinoma Hepa 1-6 Cell lLine. Asian Pac J Cancer Prev 2020; 21:1045-1050. [PMID: 32334468 PMCID: PMC7445996 DOI: 10.31557/apjcp.2020.21.4.1045] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2019] [Indexed: 12/15/2022] Open
Abstract
Background: A multistep process with an accumulation of epigenetic alterations of tumor suppressor genes (TSGs) can induce cancer. Abnormal regional hypermethylation and histone deacetylation of several TSGs has been observed in hepatocellular carcinoma (HCC). Acetylation and deacetylation of histone are carried out by histone acetyltransferase (HAT) and histone deacetylase (HDAC) respectively. Besides, DNA methylation is carried out by DNA methyltransferases (DNMTs). Previously, we evaluated the effect of DNA demethylating agents and histone deacetylase inhibitors on HCC and colon cancer. This study aimed to evaluate the effect of curcumin (CUR) in comparison with trichostatin A (TSA) on estrogen receptor alpha (ERα) reactivation, apoptotic induction, and cell growth inhibition in HCC. Methods: the cells were cultured and treated with various concentrations of CUR and TSA and the MTT assay, flow cytometry assay and Real-Time RT-PCR were achieved to determine cell viability, cell apoptosis, and ERα gene expression respectively. Results: CUR indicated dose and time-dependent antiproliferative effects (P < 0.035). A similar antiproliferative effect was observed by TSA (P < 0.001). Both compounds indicated significant apoptotic effects in all different periods (P < 0.001), CUR indicated a more significant apoptotic effect than TSA (P < 0.001). The ERα gene expression quantity was increased significantly by treatment with CUR and TSA (P <0.012). Conclusion: CUR and TSA play important roles in restoring the ERα resulting in cell growth inhibition and apoptosis induction. Therefore, ERα may be a potential target for therapeutic intervention in the treatment of HCC.
Collapse
Affiliation(s)
- Masumeh Sanaei
- Research Center for Non-Communicable Diseases, Jahrom University of Medical Sciences, Jahrom, Iran
| | - Fraidoon Kavoosi
- Research Center for Non-Communicable Diseases, Jahrom University of Medical Sciences, Jahrom, Iran
| | - Mehrnoosh Arabloo
- Student of Research Committee, Jahrom University of Medical Sciences, Jahrom, Iran
| |
Collapse
|
11
|
Kim DH, Kim HM, Huong PTT, Han HJ, Hwang J, Cha-Molstad H, Lee KH, Ryoo IJ, Kim KE, Huh YH, Ahn JS, Kwon YT, Soung NK, Kim BY. Enhanced anticancer effects of a methylation inhibitor by inhibiting a novel DNMT1 target, CEP 131, in cervical cancer. BMB Rep 2019. [PMID: 31068247 PMCID: PMC6549914 DOI: 10.5483/bmbrep.2019.52.5.055] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Methylation is a primary epigenetic mechanism regulating gene expression. 5-aza-2′-deoxycytidine is an FDA-approved drug prescribed for treatment of cancer by inhibiting DNA-Methyl-Transferase 1 (DNMT1). Results of this study suggest that prolonged treatment with 5-aza-2′-deoxycytidine could induce centrosome abnormalities in cancer cells and that CEP131, a centrosome protein, is regulated by DNMT1. Interestingly, cancer cell growth was attenuated in vitro and in vivo by inhibiting the expression of Cep131. Finally, Cep131-deficient cells were more sensitive to treatment with DNMT1 inhibitors. These findings suggest that Cep131 is a potential novel anti-cancer target. Agents that can inhibit this protein may be useful alone or in combination with DNMT1 inhibitors to treat cancer.
Collapse
Affiliation(s)
- Dong Hyun Kim
- Anticancer Agent Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Cheongju 28116; Department of Bio-Molecular Science, KRIBB School of Bioscience, Korea University of Science and Technology (UST), Daejeon 34113, Korea
| | - Hye-Min Kim
- Anticancer Agent Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Cheongju 28116, Korea
| | - Pham Thi Thu Huong
- Anticancer Agent Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Cheongju 28116, Korea
| | - Ho-Jin Han
- Anticancer Agent Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Cheongju 28116; Department of Bio-Molecular Science, KRIBB School of Bioscience, Korea University of Science and Technology (UST), Daejeon 34113, Korea
| | - Joonsung Hwang
- Anticancer Agent Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Cheongju 28116, Korea
| | - Hyunjoo Cha-Molstad
- Anticancer Agent Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Cheongju 28116, Korea
| | - Kyung Ho Lee
- Anticancer Agent Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Cheongju 28116, Korea
| | - In-Ja Ryoo
- Anticancer Agent Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Cheongju 28116, Korea
| | - Kyoon Eon Kim
- Department of Biochemistry, College of Natural Science, Chungnam National University, Daejeon 34134, Korea
| | - Yang Hoon Huh
- Center for Electron Microscopy Research, Korea Basic Science Institute, Cheongju 28119, Korea
| | - Jong Seog Ahn
- Anticancer Agent Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Cheongju 28116; Department of Bio-Molecular Science, KRIBB School of Bioscience, Korea University of Science and Technology (UST), Daejeon 34113, Korea
| | - Yong Tae Kwon
- Protein Metabolism Medical Research Center, Department of Biomedical Sciences, College of Medicine, Seoul National University, Seoul 03080, Korea
| | - Nak-Kyun Soung
- Anticancer Agent Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Cheongju 28116; Department of Bio-Molecular Science, KRIBB School of Bioscience, Korea University of Science and Technology (UST), Daejeon 34113, Korea
| | - Bo Yeon Kim
- Anticancer Agent Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Cheongju 28116; Department of Bio-Molecular Science, KRIBB School of Bioscience, Korea University of Science and Technology (UST), Daejeon 34113, Korea
| |
Collapse
|
12
|
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.
Collapse
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.
| |
Collapse
|
13
|
Epigenetic Alterations of Heat Shock Proteins (HSPs) in Cancer. Int J Mol Sci 2019; 20:ijms20194758. [PMID: 31557887 PMCID: PMC6801855 DOI: 10.3390/ijms20194758] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2019] [Revised: 09/20/2019] [Accepted: 09/23/2019] [Indexed: 12/15/2022] Open
Abstract
Heat shock proteins (HSPs) are associated with various physiological processes (protein refolding and degradation) involved in the responses to cellular stress, such as cytotoxic agents, high temperature, and hypoxia. HSPs are overexpressed in cancer cells and play roles in their apoptosis, invasion, proliferation, angiogenesis, and metastasis. The regulation or translational modification of HSPs is recognized as a therapeutic target for the development of anticancer drugs. Among the regulatory processes associated with HSP expression, the epigenetic machinery (miRNAs, histone modification, and DNA methylation) has key functions in cancer. Moreover, various epigenetic modifiers of HSP expression have also been reported as therapeutic targets and diagnostic markers of cancer. Thus, in this review, we describe the epigenetic alterations of HSP expression in cancer cells and suggest that HSPs be clinically applied as diagnostic and therapeutic markers in cancer therapy via controlled epigenetic modifiers.
Collapse
|
14
|
Norollahi SE, Mansour-Ghanaei F, Joukar F, Ghadarjani S, Mojtahedi K, Gharaei Nejad K, Hemmati H, Gharibpoor F, Khaksar R, Samadani AA. Therapeutic approach of Cancer stem cells (CSCs) in gastric adenocarcinoma; DNA methyltransferases enzymes in cancer targeted therapy. Biomed Pharmacother 2019; 115:108958. [PMID: 31075731 DOI: 10.1016/j.biopha.2019.108958] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2019] [Revised: 05/03/2019] [Accepted: 05/03/2019] [Indexed: 02/08/2023] Open
Abstract
Cancer stem cells (CSCs) show a remarkable sub class of cancer cells population which have a potential to organize and regulate stemness properties which possess a main particular responsibility for uncontrolled growth in carcinogenesis, production of different cancers in differentiated situation and also resistancy to radiotherapy and chemotherapy. Correspondingly, gastric cancer (GC) as a very serious type in cancer mortality in the world, has received a deep attention in molecular therapy recently. Besides the main characteristics of CSCs like differentiation, epithelial mesenchymal transition, self-renewal and metastasis, they are so effective in expression of stemness genes resistancy in radiotherapy and chemotherapy. In this way, the regulation of epigenetic elements including DNA methylation and the performance of DNA methyltransferase (DNMT) which is a notable epigenetic trait in GC, is of great importance. Inhibitors of DNA methylation are the first epigenetic drugs in cancer therapy. Considerably, recent studies indicate that low doses of DNMT inhibitors have a high potential in sustaining reduced DNA methylation and related with re-expression of silenced genes in tumorigenesis. Importantly, these certain doses have the ability to decrease the carcinogenesis and tumorigenesis in CSC populations within GC. Meaningly, the inhibition of DNMTs are able to reduce the accumulation of tumorigenic ability of GC CSCs. Furthermore, many epigenetic drugs have a great potential in cancer therapy, including histone methyltransferases, lysine demethylases, histone deacetylasesand, bromodomain and extra-terminal domain proteins and DNA methyltransferases inhibitors. In this review article, we try to focus on the therapeutic mechanism of DNMTs alongside with their impact on CSCs in GC.
Collapse
Affiliation(s)
- Syedeh Elham Norollahi
- Gastrointestinal and liver diseases research center, Guilan University of Medical Sciences, Rasht, Iran
| | - Fariborz Mansour-Ghanaei
- Gastrointestinal and liver diseases research center, Guilan University of Medical Sciences, Rasht, Iran
| | - Farahnaz Joukar
- Gastrointestinal and liver diseases research center, Guilan University of Medical Sciences, Rasht, Iran
| | - Shervin Ghadarjani
- Department of Neurosurgery, Guilan University of Medical Sciences, Rasht, Iran
| | - Kourosh Mojtahedi
- Gastrointestinal and liver diseases research center, Guilan University of Medical Sciences, Rasht, Iran
| | - Kaveh Gharaei Nejad
- Skin Research Center, Dermatology Department, Guilan University of Medical Sciences, Razi Hospital, Sardare Jangal Street, Rasht, Iran
| | - Hossein Hemmati
- Razi Clinical Research Development Center, Guilan University of Medical Sciences, Rasht, Iran
| | - Faeze Gharibpoor
- Gastrointestinal and liver diseases research center, Guilan University of Medical Sciences, Rasht, Iran
| | - Roya Khaksar
- Gastrointestinal and liver diseases research center, Guilan University of Medical Sciences, Rasht, Iran.
| | - Ali Akbar Samadani
- Gastrointestinal and liver diseases research center, Guilan University of Medical Sciences, Rasht, Iran.
| |
Collapse
|
15
|
Fattahi S, Golpour M, Amjadi-Moheb F, Sharifi-Pasandi M, Khodadadi P, Pilehchian-Langroudi M, Ashrafi GH, Akhavan-Niaki H. DNA methyltransferases and gastric cancer: insight into targeted therapy. Epigenomics 2018; 10:1477-1497. [PMID: 30325215 DOI: 10.2217/epi-2018-0096] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Gastric cancer is a major health problem worldwide occupying most frequent causes of cancer-related mortality. In addition to genetic modifications, epigenetic alterations catalyzed by DNA methyltransferases (DNMTs) are a well-characterized epigenetic hallmark in gastric cancer. The reversible nature of epigenetic alterations and central role of DNA methylation in diverse biological processes provides an opportunity for using DNMT inhibitors to enhance the efficacy of chemotherapeutics. In this review, we discussed key factors or mechanisms such as SNPs, infections and genetic modifications that trigger DNMTs level modification in gastric cancer, and their potential roles in cancer progression. Finally, we focused on how inhibitors of the DNMTs can most effectively be used for the treatment of gastric cancer with multidrug resistance.
Collapse
Affiliation(s)
- Sadegh Fattahi
- Cellular & Molecular Biology Research Center, Health Research Institute, Babol University of Medical Sciences, 4717647745, Babol, Iran.,North Research Center, Pasteur Institute, Amol, 4615885399, Iran
| | - Monireh Golpour
- Molecular & Cell Biology Research Center, Student Research Committee, Faculty of Medicine, Mazandaran University of Medical Science, Sari, 4817844718, Iran
| | - Fatemeh Amjadi-Moheb
- Department of Genetics, Faculty of Medicine, Babol University of Medical Sciences, 4717647745, Babol, Iran
| | - Marzieh Sharifi-Pasandi
- Molecular & Cell Biology Research Center, Student Research Committee, Faculty of Medicine, Mazandaran University of Medical Science, Sari, 4817844718, Iran
| | - Parastesh Khodadadi
- Department of Genetics, Faculty of Medicine, Babol University of Medical Sciences, 4717647745, Babol, Iran
| | | | - Gholam Hossein Ashrafi
- School of Life Science, Pharmacy & Chemistry, SEC Faculty, Cancer Theme, Kingston University London, Kingston upon Thames, London KT1 2EE, UK
| | - Haleh Akhavan-Niaki
- Department of Genetics, Faculty of Medicine, Babol University of Medical Sciences, 4717647745, Babol, Iran
| |
Collapse
|
16
|
Symmank J, Bayer C, Schmidt C, Hahn A, Pensold D, Zimmer-Bensch G. DNMT1 modulates interneuron morphology by regulating Pak6 expression through crosstalk with histone modifications. Epigenetics 2018; 13:536-556. [PMID: 29912614 DOI: 10.1080/15592294.2018.1475980] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Epigenetic mechanisms of gene regulation, including DNA methylation and histone modifications, call increasing attention in the context of development and human health. Thereby, interactions between DNA methylating enzymes and histone modifications tremendously multiply the spectrum of potential regulatory functions. Epigenetic networks are critically involved in the establishment and functionality of neuronal circuits that are composed of gamma-aminobutyric acid (GABA)-positive inhibitory interneurons and excitatory principal neurons in the cerebral cortex. We recently reported a crucial role of the DNA methyltransferase 1 (DNMT1) during the migration of immature POA-derived cortical interneurons by promoting the migratory morphology through repression of Pak6. However, the DNMT1-dependent regulation of Pak6 expression appeared to occur independently of direct DNA methylation. Here, we show that in addition to its DNA methylating activity, DNMT1 can act on gene transcription by modulating permissive H3K4 and repressive H3K27 trimethylation in developing inhibitory interneurons, similar to what was found in other cell types. In particular, the transcriptional control of Pak6, interactions of DNMT1 with the Polycomb-repressor complex 2 (PCR2) core enzyme EZH2, mediating repressive H3K27 trimethylations at regulatory regions of the Pak6 gene locus. Similar to what was observed upon Dnmt1 depletion, inhibition of EZH2 caused elevated Pak6 expression levels accompanied by increased morphological complexity, which was rescued by siRNA-mediated downregulation of Pak6 expression. Together, our data emphasise the relevance of DNMT1-dependent crosstalk with histone tail methylation for transcriptional control of genes like Pak6 required for proper cortical interneuron migration.
Collapse
Affiliation(s)
- Judit Symmank
- a Institute of Human Genetics , University Hospital Jena , Jena , Germany
| | - Cathrin Bayer
- a Institute of Human Genetics , University Hospital Jena , Jena , Germany
| | - Christiane Schmidt
- a Institute of Human Genetics , University Hospital Jena , Jena , Germany
| | - Anne Hahn
- a Institute of Human Genetics , University Hospital Jena , Jena , Germany
| | - Daniel Pensold
- a Institute of Human Genetics , University Hospital Jena , Jena , Germany
| | - Geraldine Zimmer-Bensch
- a Institute of Human Genetics , University Hospital Jena , Jena , Germany.,b Institute for Biology II , Division of Functional Epigenetics in the Animal Model, RWTH Aachen University , Aachen , Germany
| |
Collapse
|
17
|
Liu M, Wang J, Liu P. HPLC method development, validation, and impurity characterization of a potent antitumor nucleoside, T-dCyd (NSC 764276). J Pharm Biomed Anal 2016; 131:429-435. [PMID: 27661436 DOI: 10.1016/j.jpba.2016.08.034] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2016] [Revised: 08/27/2016] [Accepted: 08/28/2016] [Indexed: 11/15/2022]
Abstract
An HPLC method for the assay of an anticancer nucleoside, 4'-thio-2'-deoxycytidine (T-dCyd, NSC 764276), has been developed and validated. The stress testing of T-dCyd was carried out in accordance with ICH guidelines Q1A (R2) under acidic, alkaline, oxidative, thermolytic, and photolytic conditions. The separation of T-dCyd from its impurities and degradation products was achieved in 40min on a Luna® Phenyl-Hexyl column (150mm×4.6mm i.d., 3μm) with a gradient elution using ammonium phosphate buffer (pH 3.85) and methanol as the mobile phase. The gradient starts from 2% and ends at 80% of methanol. Detection is by UV at 282nm. LC-QTOF/MS was used to obtain mass data for characterization of impurities and degradation products. The proposed HPLC assay method was validated for specificity, linearity (concentration range 0.25-0.75mg/mL, r≥0.9998), accuracy (recovery 98.1-102.0%), precision (RSD≤1.5%), and sensitivity (LOD 0.1μg/mL). The developed method was suitable for the quality control and stability monitoring of the T-dCyd drug substance.
Collapse
Affiliation(s)
- Mingtao Liu
- SRI International, 333 Ravenswood Avenue, Menlo Park, CA, 94025, USA
| | - Jennie Wang
- SRI International, 333 Ravenswood Avenue, Menlo Park, CA, 94025, USA.
| | - Paul Liu
- Pharmaceutical Resources Branch, DCTD, NCI, 9609 Medical Center Drive, Bethesda, MD, 20892, USA.
| |
Collapse
|
18
|
Brenner C, Luciani J, Bizet M, Ndlovu M, Josseaux E, Dedeurwaerder S, Calonne E, Putmans P, Cartron PF, Defrance M, Fuks F, Deplus R. The interplay between the lysine demethylase KDM1A and DNA methyltransferases in cancer cells is cell cycle dependent. Oncotarget 2016; 7:58939-58952. [PMID: 27449289 PMCID: PMC5312287 DOI: 10.18632/oncotarget.10624] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2016] [Accepted: 07/06/2016] [Indexed: 12/12/2022] Open
Abstract
DNA methylation and histone modifications are key epigenetic regulators of gene expression, and tight connections are known between the two. DNA methyltransferases are upregulated in several tumors and aberrant DNA methylation profiles are a cancer hallmark. On the other hand, histone demethylases are upregulated in cancer cells. Previous work on ES cells has shown that the lysine demethylase KDM1A binds to DNMT1, thereby affecting DNA methylation. In cancer cells, the occurrence of this interaction has not been explored. Here we demonstrate in several tumor cell lines an interaction between KDM1A and both DNMT1 and DNMT3B. Intriguingly and in contrast to what is observed in ES cells, KDM1A depletion in cancer cells was found not to trigger any reduction in the DNMT1 or DNMT3B protein level or any change in DNA methylation. In the S-phase, furthermore, KDM1A and DNMT1 were found, to co-localize within the heterochromatin. Using P-LISA, we revealed substantially increased binding of KDM1A to DNMT1 during the S-phase. Together, our findings propose a mechanistic link between KDM1A and DNA methyltransferases in cancer cells and suggest that the KDM1A/DNMT1 interaction may play a role during replication. Our work also strengthens the idea that DNMTs can exert functions unrelated to act on DNA methylation.
Collapse
Affiliation(s)
- Carmen Brenner
- Laboratory of Cancer Epigenetics, Faculty of Medicine, ULB-Cancer Research Centre (U-CRC), Université Libre de Bruxelles, 1070 Brussels, Belgium
| | - Judith Luciani
- Laboratory of Cancer Epigenetics, Faculty of Medicine, ULB-Cancer Research Centre (U-CRC), Université Libre de Bruxelles, 1070 Brussels, Belgium
| | - Martin Bizet
- Laboratory of Cancer Epigenetics, Faculty of Medicine, ULB-Cancer Research Centre (U-CRC), Université Libre de Bruxelles, 1070 Brussels, Belgium
| | - Matladi Ndlovu
- Laboratory of Cancer Epigenetics, Faculty of Medicine, ULB-Cancer Research Centre (U-CRC), Université Libre de Bruxelles, 1070 Brussels, Belgium
| | - Eleonore Josseaux
- Laboratory of Cancer Epigenetics, Faculty of Medicine, ULB-Cancer Research Centre (U-CRC), Université Libre de Bruxelles, 1070 Brussels, Belgium
| | - Sarah Dedeurwaerder
- Laboratory of Cancer Epigenetics, Faculty of Medicine, ULB-Cancer Research Centre (U-CRC), Université Libre de Bruxelles, 1070 Brussels, Belgium
| | - Emilie Calonne
- Laboratory of Cancer Epigenetics, Faculty of Medicine, ULB-Cancer Research Centre (U-CRC), Université Libre de Bruxelles, 1070 Brussels, Belgium
| | - Pascale Putmans
- Laboratory of Cancer Epigenetics, Faculty of Medicine, ULB-Cancer Research Centre (U-CRC), Université Libre de Bruxelles, 1070 Brussels, Belgium
| | - Pierre-Francois Cartron
- Centre de Recherche en Cancérologie Nantes-Angers, INSERM, U892, Equipe Apoptose et Progression Tumorale, BP7021, 44007 Nantes, France
- Département de Recherche en Cancérologie, Faculté de Médecine, Université de Nantes, IFR26, F-4400, Nantes, France
- LaBCT, Institut de Cancérologie de l'Ouest, 44805 Nantes, Saint Herblain Cedex, France
| | - Matthieu Defrance
- Laboratory of Cancer Epigenetics, Faculty of Medicine, ULB-Cancer Research Centre (U-CRC), Université Libre de Bruxelles, 1070 Brussels, Belgium
| | - François Fuks
- Laboratory of Cancer Epigenetics, Faculty of Medicine, ULB-Cancer Research Centre (U-CRC), Université Libre de Bruxelles, 1070 Brussels, Belgium
| | - Rachel Deplus
- Laboratory of Cancer Epigenetics, Faculty of Medicine, ULB-Cancer Research Centre (U-CRC), Université Libre de Bruxelles, 1070 Brussels, Belgium
| |
Collapse
|
19
|
Ruiz Esparza-Garrido R, Torres-Márquez ME, Viedma-Rodríguez R, Velázquez-Wong AC, Salamanca-Gómez F, Rosas-Vargas H, Velázquez-Flores MÁ. Breast cancer cell line MDA-MB-231 miRNA profile expression after BIK interference: BIK involvement in autophagy. Tumour Biol 2015; 37:6749-59. [PMID: 26662110 DOI: 10.1007/s13277-015-4494-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2015] [Accepted: 11/23/2015] [Indexed: 12/19/2022] Open
Abstract
B-cell lymphoma 2 (BCL2)-interacting killer (apoptosis inducing) (BIK) has been proposed as a tumor suppressor in diverse types of cancers. However, BIK's overexpression in breast cancer (BC) and in non-small lung cancer cells (NSCLCs), associated with a poor prognosis, suggests its participation in tumor progression. In this study, we evaluated the global expression pattern of microRNAs (miRNAs), messenger RNA (mRNA) expression changes in autophagy, and autophagic flux after BIK interference. BIK gene expression was silenced by small interfering RNA (siRNA) in BC cell MDA-MB-231, and BIK interference efficiency was tested by real-time PCR and by Western blotting. BIK expression levels decreased by 75 ± 18 % in the presence of 600 nM siRNA, resulting in the abolishment of BIK expression by 94 ± 30 %. BIK interference resulted in the overexpression of 17 miRNAs that, according to the DIANA-miRPath v3.0 database, are mainly implied in the control of cell signaling, gene expression, and autophagy. The autophagy array revealed downregulation of transcripts which participate in autophagy, and their interactome revealed a complex network, where hepatocyte growth factor-regulated tyrosine kinase substrate (HGS), α-synuclein (SNCA), unc-51-like autophagy activating kinase 1/2 (ULK1/2), and mitogen-activated protein kinase 3 (MAPK3) were shown to be signaling hubs. LC3-II expression-an autophagy marker-was increased by 169 ± 25 % after BIK interference, which indicates the involvement of BIK in autophagy. Altogether, our results indicate-for the first time-that BIK controls the expression of miRNAs, as well as the autophagic flux in MDA-MB-231 cells.
Collapse
Affiliation(s)
- Ruth Ruiz Esparza-Garrido
- CONACyT Research Fellow, Functional Genomics Laboratory, Unit of Human Genetics Research, Children's Hospital, National Medical Center Century XXI, Mexican Institute of Social Security (IMSS), México, C.P. 06720, DF, México.
- Functional Genomics Laboratory, Unit of Human Genetics Research, Children's Hospital, National Medical Center Century XXI, Mexican Institute of Social Security (IMSS), México, C.P. 06720, DF, México.
| | | | - Rubí Viedma-Rodríguez
- Laboratorio de Biología del Desarrollo, Unidad de Morfología y Función Celular, Facultad de Estudios Superiores Iztacala (FES Iztacala), Universidad Nacional Autónoma de México (UNAM-México), 54090, Tlalnepantla, Estado de México, México
| | - Ana Claudia Velázquez-Wong
- Functional Genomics Laboratory, Unit of Human Genetics Research, Children's Hospital, National Medical Center Century XXI, Mexican Institute of Social Security (IMSS), México, C.P. 06720, DF, México
| | - Fabio Salamanca-Gómez
- Coordinación de Investigación en Salud, Centro Médico Nacional Siglo XXI, Instituto Mexicano del Seguro Social, México, DF, México
| | - Haydeé Rosas-Vargas
- Functional Genomics Laboratory, Unit of Human Genetics Research, Children's Hospital, National Medical Center Century XXI, Mexican Institute of Social Security (IMSS), México, C.P. 06720, DF, México
| | - Miguel Ángel Velázquez-Flores
- Functional Genomics Laboratory, Unit of Human Genetics Research, Children's Hospital, National Medical Center Century XXI, Mexican Institute of Social Security (IMSS), México, C.P. 06720, DF, México
| |
Collapse
|
20
|
Gautier JF, Porcher R, Abi Khalil C, Bellili-Munoz N, Fetita LS, Travert F, Choukem SP, Riveline JP, Hadjadj S, Larger E, Boudou P, Blondeau B, Roussel R, Ferré P, Ravussin E, Rouzet F, Marre M. Kidney Dysfunction in Adult Offspring Exposed In Utero to Type 1 Diabetes Is Associated with Alterations in Genome-Wide DNA Methylation. PLoS One 2015; 10:e0134654. [PMID: 26258530 PMCID: PMC4530883 DOI: 10.1371/journal.pone.0134654] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2014] [Accepted: 07/13/2015] [Indexed: 12/20/2022] Open
Abstract
Background Fetal exposure to hyperglycemia impacts negatively kidney development and function. Objective Our objective was to determine whether fetal exposure to moderate hyperglycemia is associated with epigenetic alterations in DNA methylation in peripheral blood cells and whether those alterations are related to impaired kidney function in adult offspring. Design Twenty nine adult, non-diabetic offspring of mothers with type 1 diabetes (T1D) (case group) were matched with 28 offspring of T1D fathers (control group) for the study of their leukocyte genome-wide DNA methylation profile (27,578 CpG sites, Human Methylation 27 BeadChip, Illumina Infinium). In a subset of 19 cases and 18 controls, we assessed renal vascular development by measuring Glomerular Filtration Rate (GFR) and Effective Renal Plasma Flow (ERPF) at baseline and during vasodilatation produced by amino acid infusion. Results Globally, DNA was under-methylated in cases vs. controls. Among the 87 CpG sites differently methylated, 74 sites were less methylated and 13 sites more methylated in cases vs. controls. None of these CpG sites were located on a gene known to be directly involved in kidney development and/or function. However, the gene encoding DNA methyltransferase 1 (DNMT1)—a key enzyme involved in gene expression during early development–was under-methylated in cases. The average methylation of the 74 under-methylated sites differently correlated with GFR in cases and controls. Conclusion Alterations in methylation profile imprinted by the hyperglycemic milieu of T1D mothers during fetal development may impact kidney function in adult offspring. The involved pathways seem to be a nonspecific imprinting process rather than specific to kidney development or function.
Collapse
Affiliation(s)
- Jean-François Gautier
- Department of Diabetes and Endocrinology, Assistance Publique—Hôpitaux de Paris, DHU FIRE, Lariboisière Hospital, University Paris-Diderot Paris-7, Paris, France
- Clinical Investigation Center, INSERM-CIC9504, Saint-Louis University Hospital, Assistance Publique—Hôpitaux de Paris, University Paris-Diderot Paris-7, Paris, France
- INSERM UMRS 1138, Cordeliers Research Center, University Pierre et Marie Curie Paris-6, Paris, France
- * E-mail:
| | - Raphaël Porcher
- Department of Biostatistics and Medical Computing, Saint-Louis University Hospital, Assistance Publique—Hôpitaux de Paris, University Paris-Diderot Paris-7, Paris, France
| | - Charbel Abi Khalil
- Department of Diabetes, Groupe Hospitalier Bichat—Claude Bernard, Assistance Publique—Hôpitaux de Paris, DHU FIRE, University Paris-Diderot Paris-7, Paris, France
| | - Naima Bellili-Munoz
- INSERM UMRS 1138, Cordeliers Research Center, University Pierre et Marie Curie Paris-6, Paris, France
| | - Lila Sabrina Fetita
- Department of Diabetes and Endocrinology, Assistance Publique—Hôpitaux de Paris, DHU FIRE, Lariboisière Hospital, University Paris-Diderot Paris-7, Paris, France
| | - Florence Travert
- Department of Diabetes, Groupe Hospitalier Bichat—Claude Bernard, Assistance Publique—Hôpitaux de Paris, DHU FIRE, University Paris-Diderot Paris-7, Paris, France
- Clinical Investigation Center, Groupe Hospitalier Bichat—Claude Bernard, Assistance Publique–Hôpitaux de Paris, University Paris-Diderot Paris-7, Paris, France
| | - Simeon-Pierre Choukem
- Department of Diabetes and Endocrinology, Assistance Publique—Hôpitaux de Paris, DHU FIRE, Lariboisière Hospital, University Paris-Diderot Paris-7, Paris, France
| | - Jean-Pierre Riveline
- INSERM UMRS 1138, Cordeliers Research Center, University Pierre et Marie Curie Paris-6, Paris, France
- Department of Diabetes and Endocrinology, Centre Hospitalier Sud Francilien, Corbeil-Essonnes, France
| | - Samy Hadjadj
- Department of Endocrinology and Diabetes, Centre Hospitalier Universitaire, Poitiers, France
| | - Etienne Larger
- Department of Diabetes, Hôtel-Dieu Hospital, Assistance Publique–Hôpitaux de Paris, Paris, France
| | - Philippe Boudou
- Unit of Transfer in Molecular Oncology and Hormonology, Saint-Louis University Hospital, Assistance Publique—Hôpitaux de Paris, Paris, France
| | - Bertrand Blondeau
- INSERM UMRS 1138, Cordeliers Research Center, University Pierre et Marie Curie Paris-6, Paris, France
| | - Ronan Roussel
- Department of Diabetes, Groupe Hospitalier Bichat—Claude Bernard, Assistance Publique—Hôpitaux de Paris, DHU FIRE, University Paris-Diderot Paris-7, Paris, France
- INSERM U695, University Paris-Diderot Paris-7, Paris, France
| | - Pascal Ferré
- INSERM UMRS 1138, Cordeliers Research Center, University Pierre et Marie Curie Paris-6, Paris, France
| | - Eric Ravussin
- Penington Biomedical Research Center, Baton Rouge, LA, United States of America
| | - François Rouzet
- Department of Nuclear Medicine, Groupe Hospitalier Bichat—Claude Bernard, Assistance Publique—Hôpitaux de Paris, University Paris-Diderot Paris-7, Paris, France
| | - Michel Marre
- Department of Diabetes, Groupe Hospitalier Bichat—Claude Bernard, Assistance Publique—Hôpitaux de Paris, DHU FIRE, University Paris-Diderot Paris-7, Paris, France
- Clinical Investigation Center, Groupe Hospitalier Bichat—Claude Bernard, Assistance Publique–Hôpitaux de Paris, University Paris-Diderot Paris-7, Paris, France
- INSERM U695, University Paris-Diderot Paris-7, Paris, France
| |
Collapse
|
21
|
Lardenoije R, Iatrou A, Kenis G, Kompotis K, Steinbusch HWM, Mastroeni D, Coleman P, Lemere CA, Hof PR, van den Hove DLA, Rutten BPF. The epigenetics of aging and neurodegeneration. Prog Neurobiol 2015; 131:21-64. [PMID: 26072273 PMCID: PMC6477921 DOI: 10.1016/j.pneurobio.2015.05.002] [Citation(s) in RCA: 246] [Impact Index Per Article: 27.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2014] [Revised: 05/13/2015] [Accepted: 05/13/2015] [Indexed: 12/14/2022]
Abstract
Epigenetics is a quickly growing field encompassing mechanisms regulating gene expression that do not involve changes in the genotype. Epigenetics is of increasing relevance to neuroscience, with epigenetic mechanisms being implicated in brain development and neuronal differentiation, as well as in more dynamic processes related to cognition. Epigenetic regulation covers multiple levels of gene expression; from direct modifications of the DNA and histone tails, regulating the level of transcription, to interactions with messenger RNAs, regulating the level of translation. Importantly, epigenetic dysregulation currently garners much attention as a pivotal player in aging and age-related neurodegenerative disorders, such as Alzheimer's disease, Parkinson's disease, and Huntington's disease, where it may mediate interactions between genetic and environmental risk factors, or directly interact with disease-specific pathological factors. We review current knowledge about the major epigenetic mechanisms, including DNA methylation and DNA demethylation, chromatin remodeling and non-coding RNAs, as well as the involvement of these mechanisms in normal aging and in the pathophysiology of the most common neurodegenerative diseases. Additionally, we examine the current state of epigenetics-based therapeutic strategies for these diseases, which either aim to restore the epigenetic homeostasis or skew it to a favorable direction to counter disease pathology. Finally, methodological challenges of epigenetic investigations and future perspectives are discussed.
Collapse
Affiliation(s)
- Roy Lardenoije
- School for Mental Health and Neuroscience (MHeNS), Department of Psychiatry and Neuropsychology, Maastricht University, Universiteitssingel 50, 6200 MD Maastricht, The Netherlands
| | - Artemis Iatrou
- School for Mental Health and Neuroscience (MHeNS), Department of Psychiatry and Neuropsychology, Maastricht University, Universiteitssingel 50, 6200 MD Maastricht, The Netherlands
| | - Gunter Kenis
- School for Mental Health and Neuroscience (MHeNS), Department of Psychiatry and Neuropsychology, Maastricht University, Universiteitssingel 50, 6200 MD Maastricht, The Netherlands
| | - Konstantinos Kompotis
- Center for Integrative Genomics, University of Lausanne, Genopode Building, 1015 Lausanne-Dorigny, Switzerland
| | - Harry W M Steinbusch
- School for Mental Health and Neuroscience (MHeNS), Department of Psychiatry and Neuropsychology, Maastricht University, Universiteitssingel 50, 6200 MD Maastricht, The Netherlands
| | - Diego Mastroeni
- School for Mental Health and Neuroscience (MHeNS), Department of Psychiatry and Neuropsychology, Maastricht University, Universiteitssingel 50, 6200 MD Maastricht, The Netherlands; L.J. Roberts Alzheimer's Disease Center, Banner Sun Health Research Institute, 10515 W. Santa Fe Drive, Sun City, AZ 85351, USA
| | - Paul Coleman
- L.J. Roberts Alzheimer's Disease Center, Banner Sun Health Research Institute, 10515 W. Santa Fe Drive, Sun City, AZ 85351, USA
| | - Cynthia A Lemere
- Center for Neurologic Diseases, Department of Neurology, Brigham and Women's Hospital, Harvard Medical School, 77 Avenue Louis Pasteur, Boston, MA 02115, USA
| | - Patrick R Hof
- Fishberg Department of Neuroscience and Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, New York, NY 10029, USA
| | - Daniel L A van den Hove
- School for Mental Health and Neuroscience (MHeNS), Department of Psychiatry and Neuropsychology, Maastricht University, Universiteitssingel 50, 6200 MD Maastricht, The Netherlands; Laboratory of Translational Neuroscience, Department of Psychiatry, Psychosomatics and Psychotherapy, University of Wuerzburg, Fuechsleinstrasse 15, 97080 Wuerzburg, Germany
| | - Bart P F Rutten
- School for Mental Health and Neuroscience (MHeNS), Department of Psychiatry and Neuropsychology, Maastricht University, Universiteitssingel 50, 6200 MD Maastricht, The Netherlands.
| |
Collapse
|
22
|
Song J, Du Z, Ravasz M, Dong B, Wang Z, Ewing RM. A Protein Interaction between β-Catenin and Dnmt1 Regulates Wnt Signaling and DNA Methylation in Colorectal Cancer Cells. Mol Cancer Res 2015; 13:969-81. [PMID: 25753001 DOI: 10.1158/1541-7786.mcr-13-0644] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2013] [Accepted: 01/26/2015] [Indexed: 01/03/2023]
Abstract
UNLABELLED Aberrant activation of the Wnt signaling pathway is an important step in the initiation and progression of tumor development in diverse cancers. The central effector of canonical Wnt signaling, β-catenin (CTNNB1), is a multifunctional protein, and has been extensively studied with respect to its roles in cell-cell adhesion and in regulation of Wnt-driven transcription. Here, a novel mass spectrometry-based proteomics technique in colorectal cancer cells expressing stabilized β-catenin, was used to identify a protein-protein interaction between β-catenin and DNA methyltransferase I (Dnmt1) protein, the primary regulator of DNA methylation patterns in mammalian cells. Dnmt1 and β-catenin strongly colocalized in the nuclei of colorectal cancer cells, and the interaction is mediated by the central domain of the Dnmt1 protein. Dnmt1 protein abundance is dependent upon the levels of β-catenin, and is increased in cells expressing stabilized mutant β-catenin. Conversely, the Dnmt1 regulates the levels of nuclear β-catenin and β-catenin/TCF-driven transcription. In addition, lysine-specific demethylase 1 (LSD1/KDM1A), a regulator of DNMT1 stability, was identified as a component of the Dnmt1-β-catenin protein complex and perturbation of the Dnmt1-β-catenin interaction altered DNA methylation. In summary, a functional protein-protein interaction was identified between two critically important oncoproteins, in turn revealing a link between Wnt signaling and downstream nuclear functions mediated by Dnmt1. IMPLICATIONS Two critical oncoproteins, Dnmt1 and β-catenin, mutually regulate one each other's levels and activities in colorectal cancer cells.
Collapse
Affiliation(s)
- Jing Song
- Center for Proteomics and Bioinformatics, Case Western Reserve University, Cleveland, Ohio
| | - Zhanwen Du
- Department of Genetics and Genome Science, Case Western Reserve University, Cleveland, Ohio
| | - Mate Ravasz
- Centre for Biological Sciences, University of Southampton, Southampton, United Kingdom
| | - Bohan Dong
- Department of Genetics and Genome Science, Case Western Reserve University, Cleveland, Ohio. Department of Biochemistry, Wan Nan Medical College, Wu Hu, An Hui, China
| | - Zhenghe Wang
- Department of Genetics and Genome Science, Case Western Reserve University, Cleveland, Ohio.
| | - Rob M Ewing
- Centre for Biological Sciences, University of Southampton, Southampton, United Kingdom.
| |
Collapse
|
23
|
Jacob V, Chernyavskaya Y, Chen X, Tan PS, Kent B, Hoshida Y, Sadler KC. DNA hypomethylation induces a DNA replication-associated cell cycle arrest to block hepatic outgrowth in uhrf1 mutant zebrafish embryos. Development 2015; 142:510-21. [PMID: 25564650 DOI: 10.1242/dev.115980] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
UHRF1 (ubiquitin-like, containing PHD and RING finger domains, 1) recruits DNMT1 to hemimethylated DNA during replication and is essential for maintaining DNA methylation. uhrf1 mutant zebrafish have global DNA hypomethylation and display embryonic defects, including a small liver, and they die as larvae. We make the surprising finding that, despite their reduced organ size, uhrf1 mutants express high levels of genes controlling S-phase and have many more cells undergoing DNA replication, as measured by BrdU incorporation. In contrast to wild-type hepatocytes, which are continually dividing during hepatic outgrowth and thus dilute the BrdU label, uhrf1 mutant hepatocytes retain BrdU throughout outgrowth, reflecting cell cycle arrest. Pulse-chase-pulse experiments with BrdU and EdU, and DNA content analysis indicate that uhrf1 mutant cells undergo DNA re-replication and that apoptosis is the fate of many of the re-replicating and arrested hepatocytes. Importantly, the DNA re-replication phenotype and hepatic outgrowth failure are preceded by global loss of DNA methylation. Moreover, uhrf1 mutants are phenocopied by mutation of dnmt1, and Dnmt1 knockdown in uhrf1 mutants enhances their small liver phenotype. Together, these data indicate that unscheduled DNA replication and failed cell cycle progression leading to apoptosis are the mechanisms by which DNA hypomethylation prevents organ expansion in uhrf1 mutants. We propose that cell cycle arrest leading to apoptosis is a strategy that restricts propagation of epigenetically damaged cells during embryogenesis.
Collapse
Affiliation(s)
- Vinitha Jacob
- Department of Medicine, Division of Liver Diseases, Icahn School of Medicine at Mount Sinai, 1 Gustave L. Levy Place, Box 1020, New York, NY 10029, USA Department of Developmental and Regenerative Biology, Icahn School of Medicine at Mount Sinai, 1 Gustave L. Levy Place, Box 1020, New York, NY 10029, USA Graduate School of Biomedical Sciences, Icahn School of Medicine at Mount Sinai, 1 Gustave L. Levy Place, Box 1020, New York, NY 10029, USA
| | - Yelena Chernyavskaya
- Department of Medicine, Division of Liver Diseases, Icahn School of Medicine at Mount Sinai, 1 Gustave L. Levy Place, Box 1020, New York, NY 10029, USA Department of Developmental and Regenerative Biology, Icahn School of Medicine at Mount Sinai, 1 Gustave L. Levy Place, Box 1020, New York, NY 10029, USA
| | - Xintong Chen
- Department of Medicine, Division of Liver Diseases, Icahn School of Medicine at Mount Sinai, 1 Gustave L. Levy Place, Box 1020, New York, NY 10029, USA Liver Cancer Program, Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, 1 Gustave L. Levy Place, Box 1020, New York, NY 10029, USA
| | - Poh Seng Tan
- Department of Medicine, Division of Liver Diseases, Icahn School of Medicine at Mount Sinai, 1 Gustave L. Levy Place, Box 1020, New York, NY 10029, USA Liver Cancer Program, Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, 1 Gustave L. Levy Place, Box 1020, New York, NY 10029, USA Division of Gastroenterology and Hepatology, University Medicine Cluster, National University Health System, Singapore
| | - Brandon Kent
- Department of Medicine, Division of Liver Diseases, Icahn School of Medicine at Mount Sinai, 1 Gustave L. Levy Place, Box 1020, New York, NY 10029, USA Department of Developmental and Regenerative Biology, Icahn School of Medicine at Mount Sinai, 1 Gustave L. Levy Place, Box 1020, New York, NY 10029, USA Graduate School of Biomedical Sciences, Icahn School of Medicine at Mount Sinai, 1 Gustave L. Levy Place, Box 1020, New York, NY 10029, USA
| | - Yujin Hoshida
- Department of Medicine, Division of Liver Diseases, Icahn School of Medicine at Mount Sinai, 1 Gustave L. Levy Place, Box 1020, New York, NY 10029, USA Graduate School of Biomedical Sciences, Icahn School of Medicine at Mount Sinai, 1 Gustave L. Levy Place, Box 1020, New York, NY 10029, USA Liver Cancer Program, Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, 1 Gustave L. Levy Place, Box 1020, New York, NY 10029, USA
| | - Kirsten C Sadler
- Department of Medicine, Division of Liver Diseases, Icahn School of Medicine at Mount Sinai, 1 Gustave L. Levy Place, Box 1020, New York, NY 10029, USA Department of Developmental and Regenerative Biology, Icahn School of Medicine at Mount Sinai, 1 Gustave L. Levy Place, Box 1020, New York, NY 10029, USA Graduate School of Biomedical Sciences, Icahn School of Medicine at Mount Sinai, 1 Gustave L. Levy Place, Box 1020, New York, NY 10029, USA
| |
Collapse
|
24
|
Tong Z, Han C, Qiang M, Wang W, Lv J, Zhang S, Luo W, Li H, Luo H, Zhou J, Wu B, Su T, Yang X, Wang X, Liu Y, He R. Age-related formaldehyde interferes with DNA methyltransferase function, causing memory loss in Alzheimer's disease. Neurobiol Aging 2015; 36:100-10. [PMID: 25282336 DOI: 10.1016/j.neurobiolaging.2014.07.018] [Citation(s) in RCA: 65] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2014] [Revised: 07/14/2014] [Accepted: 07/14/2014] [Indexed: 02/05/2023]
Abstract
Hippocampus-related topographic amnesia is the most common symptom of memory disorders in Alzheimer's disease (AD) patients. Recent studies have revealed that experience-mediated DNA methylation, which is regulated by enzymes with DNA methyltransferase (DNMT) activity, is required for the formation of recent memory as well as the maintenance of remote memory. Notably, overexpression of DNMT3a in the hippocampus can reverse spatial memory deficits in aged mice. However, a decline in global DNA methylation was found in the autopsied hippocampi of patients with AD. Exactly, what endogenous factors that affect DNA methylation still remain to be elucidated. Here, we report a marked increase in endogenous formaldehyde levels is associated with a decline in global DNA methylation in the autopsied hippocampus from AD patients. In vitro and in vivo results show that formaldehyde in excess of normal physiological levels reduced global DNA methylation by interfering DNMTs. Interestingly, intrahippocampal injection of excess formaldehyde before spatial learning in healthy adult rats can mimic the learning difficulty of early stage of AD. Moreover, injection of excess formaldehyde after spatial learning can mimic the loss of remote spatial memory observed in late stage of AD. These findings suggest that aging-associated formaldehyde contributes to topographic amnesia in AD patients.
Collapse
Affiliation(s)
- Zhiqian Tong
- State Key Laboratory of Brain and Cognitive Sciences, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China; Alzheimer's Disease Center, Beijing Institute for Brain Disorders, Capital Medical University, Beijing, China
| | - Chanshuai Han
- State Key Laboratory of Brain and Cognitive Sciences, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China; University of the Chinese Academy of Sciences, Beijing, China
| | - Min Qiang
- State Key Laboratory of Brain and Cognitive Sciences, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China; University of the Chinese Academy of Sciences, Beijing, China
| | | | - Jihui Lv
- Beijing Geriatric Hospital, Beijing, China
| | | | - Wenhong Luo
- Central Laboratory, Shantou University Medical College, Guangdong, China
| | - Hui Li
- Central Laboratory, Shantou University Medical College, Guangdong, China
| | - Hongjun Luo
- Central Laboratory, Shantou University Medical College, Guangdong, China
| | - Jiangning Zhou
- University of Science and Technology of China, Anhui, China
| | - Beibei Wu
- State Key Laboratory of Brain and Cognitive Sciences, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China; University of the Chinese Academy of Sciences, Beijing, China
| | - Tao Su
- State Key Laboratory of Brain and Cognitive Sciences, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China; University of the Chinese Academy of Sciences, Beijing, China
| | - Xu Yang
- Hubei Key Laboratory of Genetic Regulation and Integrative Biology, College of Life Science, Huazhong Normal University, Wuhan, China
| | - Xiaomin Wang
- Alzheimer's Disease Center, Beijing Institute for Brain Disorders, Capital Medical University, Beijing, China
| | - Ying Liu
- State Key Laboratory of Brain and Cognitive Sciences, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
| | - Rongqiao He
- State Key Laboratory of Brain and Cognitive Sciences, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China; Alzheimer's Disease Center, Beijing Institute for Brain Disorders, Capital Medical University, Beijing, China; Key Laboratory of Mental Health, Institute of Psychology, Chinese Academy of Sciences, Beijing, China.
| |
Collapse
|
25
|
Novel DNA methyltransferase-1 (DNMT1) depleting anticancer nucleosides, 4'-thio-2'-deoxycytidine and 5-aza-4'-thio-2'-deoxycytidine. Cancer Chemother Pharmacol 2014; 74:291-302. [PMID: 24908436 DOI: 10.1007/s00280-014-2503-z] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2013] [Accepted: 05/27/2014] [Indexed: 10/25/2022]
Abstract
PURPOSE Currently approved DNA hypomethylating nucleosides elicit their effects in part by depleting DNA methyltransferase I (DNMT1). However, their low response rates and adverse effects continue to drive the discovery of newer DNMT1 depleting agents. Herein, we identified two novel 2'-deoxycytidine (dCyd) analogs, 4'-thio-2'-deoxycytidine (T-dCyd) and 5-aza-4'-thio-2'-deoxycytidine (aza-T-dCyd) that potently deplete DNMT1 in both in vitro and in vivo models of cancer and concomitantly inhibit tumor growth. METHODS DNMT1 protein levels in in vitro and in vivo cancer models were determined by Western blotting and antitumor efficacy was evaluated using xenografts. Effects on CpG methylation were evaluated using methylation-specific PCR. T-dCyd metabolism was evaluated using radiolabeled substrate. RESULTS T-dCyd markedly depleted DNMT1 in CCRF-CEM and KG1a leukemia and NCI-H23 lung carcinoma cell lines, while it was ineffective in the HCT-116 colon or IGROV-1 ovarian tumor lines. On the other hand, aza-T-dCyd potently depleted DNMT1 in all of these lines indicating that dCyd analogs with minor structural dissimilarities induce different DNMT1 turnover mechanisms. Although T-dCyd was deaminated to 4'-thio-2'-deoxyuridine, very little was converted to 4'-thio-thymidine nucleotides, suggesting that inhibition of thymidylate synthase would be minimal with 4'-thio dCyd analogs. Both T-dCyd and aza-T-dCyd also depleted DNMT1 in human tumor xenografts and markedly reduced in vivo tumor growth. Interestingly, the selectivity index of aza-T-dCyd was at least tenfold greater than that of decitabine. CONCLUSIONS Collectively, these data show that 4'-thio modified dCyd analogs, such as T-dCyd or aza-T-dCyd, could be a new source of clinically effective DNMT1 depleting anticancer compounds with less toxicity.
Collapse
|
26
|
Song Y, Miyaki K, Suzuki T, Sasaki Y, Tsutsumi A, Kawakami N, Shimazu A, Takahashi M, Inoue A, Kan C, Kurioka S, Shimbo T. Altered DNA methylation status of human brain derived neurotrophis factor gene could be useful as biomarker of depression. Am J Med Genet B Neuropsychiatr Genet 2014; 165B:357-64. [PMID: 24801253 PMCID: PMC4321058 DOI: 10.1002/ajmg.b.32238] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/04/2013] [Accepted: 04/14/2014] [Indexed: 12/15/2022]
Abstract
Brain-derived neurotrophic factor (BDNF) is involved in the survival, development, and synaptic plasticity of neurons. BDNF is believed to be associated with the pathophysiology of psychiatric disorders. Several studies have suggested the relevance of DNA methylation in its promoter region with depression. Here, we report different methylation statuses in groups with different depressive scores or undergoing different levels of job-stress. DNA samples were extracted from the saliva of 774 Japanese workers, and the methylation status was determined using the Illumina HumanMethylation 450 K Microarray. Depressive symptoms were measured using the Kessler's K6 questionnaire. Job-stress scales were assessed via a self-administered questionnaire. Independent DNA pools were formed based on K6 and job-strain scores, and the methylation levels were compared among these pools. The average DNA methylation rate was significantly decreased in the highest K6 score group compared to the lowest group (methylated signals, 14.2% vs. 16.5%, P = 2 · 16 × 10(-198)). This difference remained for the CpG island in the promoter region (10.4% vs. 5.8%, P = 3 · 67 × 10(-133)). Regarding the job-strain score, there was a slight increase in the methylation level of the whole gene in the group with the highest score compared to that with the lowest score; however, these groups showed no difference in the promoter region. Our results revealed significant changes in the DNA methylation status of the complete human BDNF gene in persons with depression compared to normal individuals, especially in the promoter region of exon 1. This indicates that DNA methylation in this gene is a promising biomarker for diagnosing depression.
Collapse
Affiliation(s)
- Yixuan Song
- Department of Clinical Research and Informatics, National Center for Global Health and MedicineTokyo, Japan
| | - Koichi Miyaki
- Department of Clinical Research and Informatics, National Center for Global Health and MedicineTokyo, Japan,*Correspondence to:, Koichi Miyaki, M.D., Ph.D., Department of Clinical Research and Informatics, National Center for Global Health and Medicine, Toyama 1-21-1, Shinjuku-ku, Tokyo, 162-8655, Japan., E-mail:
| | - Tomoko Suzuki
- Department of Clinical Research and Informatics, National Center for Global Health and MedicineTokyo, Japan
| | - Yasuharu Sasaki
- Department of Clinical Research and Informatics, National Center for Global Health and MedicineTokyo, Japan
| | - Akizumi Tsutsumi
- Department of Public Health, Kitasato University School of MedicineSagamihara, Kanagawa, Japan
| | - Norito Kawakami
- Department of Mental Health, Tokyo University Graduate School of MedicineTokyo, Japan
| | - Akihito Shimazu
- Department of Mental Health, Tokyo University Graduate School of MedicineTokyo, Japan
| | - Masaya Takahashi
- Health Administration and Psychosocial Factor Research Group, National Institute of Occupational Safety and HealthKawasaki, Kanagawa, Japan
| | - Akiomi Inoue
- Department of Mental HealthInstitute of Industrial Ecological Sciences, University of Occupational and Environmental HealthKitakyushu, Fukuoka, Japan
| | - Chiemi Kan
- Department of Mental Health, Tokyo University Graduate School of MedicineTokyo, Japan
| | - Sumiko Kurioka
- Department of Health Policy and Management, University of Occupational and Environmental HealthKitakyushu, Fukuoka, Japan
| | - Takuro Shimbo
- Department of Clinical Research and Informatics, National Center for Global Health and MedicineTokyo, Japan
| |
Collapse
|
27
|
Campion EM, Hakimjavadi R, Loughran ST, Phelan S, Smith SM, D'Souza BN, Tierney RJ, Bell AI, Cahill PA, Walls D. Repression of the proapoptotic cellular BIK/NBK gene by Epstein-Barr virus antagonizes transforming growth factor β1-induced B-cell apoptosis. J Virol 2014; 88:5001-13. [PMID: 24554662 PMCID: PMC3993823 DOI: 10.1128/jvi.03642-13] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2013] [Accepted: 02/13/2014] [Indexed: 01/14/2023] Open
Abstract
UNLABELLED The Epstein-Barr virus (EBV) establishes a lifelong latent infection in humans. EBV infection of primary B cells causes cell activation and proliferation, a process driven by the viral latency III gene expression program, which includes EBV nuclear proteins (EBNAs), latent membrane proteins, and untranslated RNAs, including microRNAs. Some latently infected cells enter the long-lived memory B-cell compartment and express only EBNA1 transiently (Lat I) or no EBV protein at all (Lat 0). Targeting the molecular machinery that controls B-cell fate decisions, including the Bcl-2 family of apoptosis-regulating proteins, is crucial to the EBV cycle of infection. Here, we show that BIK (also known as NBK), which encodes a proapoptotic "sensitizer" protein, is repressed by the EBNA2-driven Lat III program but not the Lat I program. BIK repression occurred soon after infection of primary B cells by EBV but not by a recombinant EBV in which the EBNA2 gene had been knocked out. Ectopic BIK induced apoptosis in Lat III cells by a mechanism dependent on its BH3 domain and the activation of caspases. We show that EBNA2 represses BIK in EBV-negative B-cell lymphoma-derived cell lines and that this host-virus interaction can inhibit the proapoptotic effect of transforming growth factor β1 (TGF-β1), a key physiological mediator of B-cell homeostasis. Reduced levels of TGF-β1-associated regulatory SMAD proteins were bound to the BIK promoter in response to EBV Lat III or ectopic EBNA2. These data are evidence of an additional mechanism used by EBV to promote B-cell survival, namely, the transcriptional repression of the BH3-only sensitizer BIK. IMPORTANCE Over 90% of adult humans are infected with the Epstein-Barr virus (EBV). EBV establishes a lifelong silent infection, with its DNA residing in small numbers of blood B cells that are a reservoir from which low-level virus reactivation and shedding in saliva intermittently occur. Importantly, EBV DNA is found in some B-cell-derived tumors in which viral genes play a key role in tumor cell emergence and progression. Here, we report for the first time that EBV can shut off a B-cell gene called BIK. When activated by a molecular signal called transforming growth factor β1 (TGF-β1), BIK plays an important role in killing unwanted B cells, including those infected by viruses. We describe the key EBV-B-cell molecular interactions that lead to BIK shutoff. These findings further our knowledge of how EBV prevents the death of its host cell during infection. They are also relevant to certain posttransplant lymphomas where unregulated cell growth is caused by EBV genes.
Collapse
Affiliation(s)
- Eva M. Campion
- School of Biotechnology and National Centre for Sensor Research, Dublin City University, Dublin, Ireland
| | - Roya Hakimjavadi
- School of Biotechnology and National Centre for Sensor Research, Dublin City University, Dublin, Ireland
| | - Sinéad T. Loughran
- School of Biotechnology and National Centre for Sensor Research, Dublin City University, Dublin, Ireland
| | - Susan Phelan
- School of Biotechnology and National Centre for Sensor Research, Dublin City University, Dublin, Ireland
| | - Sinéad M. Smith
- School of Biotechnology and National Centre for Sensor Research, Dublin City University, Dublin, Ireland
| | - Brendan N. D'Souza
- School of Biotechnology and National Centre for Sensor Research, Dublin City University, Dublin, Ireland
| | - Rosemary J. Tierney
- School of Cancer Sciences, College of Medicine and Dental Sciences, University of Birmingham, Edgbaston, Birmingham, United Kingdom
| | - Andrew I. Bell
- School of Cancer Sciences, College of Medicine and Dental Sciences, University of Birmingham, Edgbaston, Birmingham, United Kingdom
| | - Paul A. Cahill
- School of Biotechnology and National Centre for Sensor Research, Dublin City University, Dublin, Ireland
- Vascular Biology Research Group, School of Biotechnology, Dublin City University, Dublin, Ireland
| | - Dermot Walls
- School of Biotechnology and National Centre for Sensor Research, Dublin City University, Dublin, Ireland
| |
Collapse
|
28
|
Crichton JH, Dunican DS, MacLennan M, Meehan RR, Adams IR. Defending the genome from the enemy within: mechanisms of retrotransposon suppression in the mouse germline. Cell Mol Life Sci 2014; 71:1581-605. [PMID: 24045705 PMCID: PMC3983883 DOI: 10.1007/s00018-013-1468-0] [Citation(s) in RCA: 72] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2013] [Revised: 08/27/2013] [Accepted: 08/29/2013] [Indexed: 12/15/2022]
Abstract
The viability of any species requires that the genome is kept stable as it is transmitted from generation to generation by the germ cells. One of the challenges to transgenerational genome stability is the potential mutagenic activity of transposable genetic elements, particularly retrotransposons. There are many different types of retrotransposon in mammalian genomes, and these target different points in germline development to amplify and integrate into new genomic locations. Germ cells, and their pluripotent developmental precursors, have evolved a variety of genome defence mechanisms that suppress retrotransposon activity and maintain genome stability across the generations. Here, we review recent advances in understanding how retrotransposon activity is suppressed in the mammalian germline, how genes involved in germline genome defence mechanisms are regulated, and the consequences of mutating these genome defence genes for the developing germline.
Collapse
Affiliation(s)
- James H. Crichton
- MRC Human Genetics Unit, MRC Institute of Genetics and Molecular Medicine, University of Edinburgh, Western General Hospital, Crewe Road, Edinburgh, EH4 2XU UK
| | - Donncha S. Dunican
- MRC Human Genetics Unit, MRC Institute of Genetics and Molecular Medicine, University of Edinburgh, Western General Hospital, Crewe Road, Edinburgh, EH4 2XU UK
| | - Marie MacLennan
- MRC Human Genetics Unit, MRC Institute of Genetics and Molecular Medicine, University of Edinburgh, Western General Hospital, Crewe Road, Edinburgh, EH4 2XU UK
| | - Richard R. Meehan
- MRC Human Genetics Unit, MRC Institute of Genetics and Molecular Medicine, University of Edinburgh, Western General Hospital, Crewe Road, Edinburgh, EH4 2XU UK
| | - Ian R. Adams
- MRC Human Genetics Unit, MRC Institute of Genetics and Molecular Medicine, University of Edinburgh, Western General Hospital, Crewe Road, Edinburgh, EH4 2XU UK
| |
Collapse
|
29
|
Yang L, Huang K, Li X, Du M, Kang X, Luo X, Gao L, Wang C, Zhang Y, Zhang C, Tong Q, Huang K, Zhang F, Huang D. Identification of poly(ADP-ribose) polymerase-1 as a cell cycle regulator through modulating Sp1 mediated transcription in human hepatoma cells. PLoS One 2013; 8:e82872. [PMID: 24367566 PMCID: PMC3868549 DOI: 10.1371/journal.pone.0082872] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2013] [Accepted: 11/06/2013] [Indexed: 11/25/2022] Open
Abstract
The transcription factor Sp1 is implicated in the activation of G0/G1 phase genes. Modulation of Sp1 transcription activities may affect G1-S checkpoint, resulting in changes in cell proliferation. In this study, our results demonstrated that activated poly(ADP-ribose) polymerase 1 (PARP-1) promoted cell proliferation by inhibiting Sp1 signaling pathway. Cell proliferation and cell cycle assays demonstrated that PARP inhibitors or PARP-1 siRNA treatment significantly inhibited proliferation of hepatoma cells and induced G0/G1 cell cycle arrest in hepatoma cells, while overexpression of PARP-1 or PARP-1 activator treatment promoted cell cycle progression. Simultaneously, inhibition of PARP-1 enhanced the expression of Sp1-mediated checkpoint proteins, such as p21 and p27. In this study, we also showed that Sp1 was poly(ADP-ribosyl)ated by PARP-1 in hepatoma cells. Poly(ADP-ribosyl)ation suppressed Sp1 mediated transcription through preventing Sp1 binding to the Sp1 response element present in the promoters of target genes. Taken together, these data indicated that PARP-1 inhibition attenuated the poly(ADP-ribosyl)ation of Sp1 and significantly increased the expression of Sp1 target genes, resulting in G0/G1 cell cycle arrest and the decreased proliferative ability of the hepatoma cells.
Collapse
Affiliation(s)
- Liu Yang
- Department of Cardiovascular Diseases, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Kun Huang
- Department of Cardiovascular Diseases, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China ; Clinical Center for Human Genomic Research, Union Hospital, Huazhong University of Science and Technology, Wuhan, China
| | - Xiangrao Li
- Department of Cardiovascular Diseases, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Meng Du
- Department of Cardiovascular Diseases, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Xiang Kang
- Department of Obstetrics and Gynecology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Xi Luo
- Department of Cardiovascular Diseases, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Lu Gao
- Department of Cardiovascular Diseases, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Cheng Wang
- Department of Cardiovascular Diseases, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Yanqing Zhang
- Department of Cardiovascular Diseases, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Chun Zhang
- Clinical Center for Human Genomic Research, Union Hospital, Huazhong University of Science and Technology, Wuhan, China
| | - Qiangsong Tong
- Clinical Center for Human Genomic Research, Union Hospital, Huazhong University of Science and Technology, Wuhan, China
| | - Kai Huang
- Department of Cardiovascular Diseases, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China ; Clinical Center for Human Genomic Research, Union Hospital, Huazhong University of Science and Technology, Wuhan, China
| | - Fengxiao Zhang
- Department of Cardiovascular Diseases, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China ; Clinical Center for Human Genomic Research, Union Hospital, Huazhong University of Science and Technology, Wuhan, China
| | - Dan Huang
- Department of Cardiovascular Diseases, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China ; Clinical Center for Human Genomic Research, Union Hospital, Huazhong University of Science and Technology, Wuhan, China
| |
Collapse
|
30
|
Armstrong VL, Rakoczy S, Rojanathammanee L, Brown-Borg HM. Expression of DNA methyltransferases is influenced by growth hormone in the long-living Ames dwarf mouse in vivo and in vitro. J Gerontol A Biol Sci Med Sci 2013; 69:923-33. [PMID: 24201695 DOI: 10.1093/gerona/glt133] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Methyltransferase expression and DNA methylation are linked to aging and age-related disease. We utilized 3-, 12-, and 24-month-old Ames dwarf and their wild-type siblings to examine the genotype and age-related differences in the expression of methyltransferase enzymes related to DNA methylation in the liver, glycine-N-methyltransferase and DNA methyltransferase (DNMT). We found that DNMT proteins and transcripts are differentially expressed in dwarf mice compared with wild-type siblings that can be attributed to age and/or genotype. However, DNMT1 protein expression is drastically reduced compared with wild-type controls at every age. DNMT3a protein levels coincide with differences observed in DNMT activity. Growth hormone appears to modulate expression of DNMT1 and 3a in dwarf liver tissue and primary hepatocytes. Therefore, growth hormone may contribute to age-related processes, DNA methylation, and, ultimately, longevity.
Collapse
Affiliation(s)
- Vanessa L Armstrong
- Department of Pharmacology, Physiology, and Therapeutics, University of North Dakota School of Medicine and Health Sciences, Grand Forks
| | - Sharlene Rakoczy
- Department of Pharmacology, Physiology, and Therapeutics, University of North Dakota School of Medicine and Health Sciences, Grand Forks
| | - Lalida Rojanathammanee
- Department of Pharmacology, Physiology, and Therapeutics, University of North Dakota School of Medicine and Health Sciences, Grand Forks
| | - Holly M Brown-Borg
- Department of Pharmacology, Physiology, and Therapeutics, University of North Dakota School of Medicine and Health Sciences, Grand Forks.
| |
Collapse
|
31
|
Lee J, Hwang YJ, Kim KY, Kowall NW, Ryu H. Epigenetic mechanisms of neurodegeneration in Huntington's disease. Neurotherapeutics 2013; 10:664-76. [PMID: 24006238 PMCID: PMC3805871 DOI: 10.1007/s13311-013-0206-5] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Huntington's disease (HD) is an incurable and fatal hereditary neurodegenerative disorder of mid-life onset characterized by chorea, emotional distress, and progressive cognitive decline. HD is caused by an expansion of CAG repeats coding for glutamine (Q) in exon 1 of the huntingtin gene. Recent studies suggest that epigenetic modifications may play a key role in HD pathogenesis. Alterations of the epigenetic "histone code" lead to chromatin remodeling and deregulation of neuronal gene transcription that are prominently linked to HD pathogenesis. Furthermore, specific noncoding RNAs and microRNAs are associated with neuronal damage in HD. In this review, we discuss how DNA methylation, post-translational modifications of histone, and noncoding RNA function are affected and involved in HD pathogenesis. In addition, we summarize the therapeutic effects of histone deacetylase inhibitors and DNA binding drugs on epigenetic modifications and neuropathological sequelae in HD. Our understanding of the role of these epigenetic mechanisms may lead to the identification of novel biological markers and new therapeutic targets to treat HD.
Collapse
Affiliation(s)
- Junghee Lee
- />Boston University Alzheimer’s Disease Center and Department of Neurology, Boston University School of Medicine, Boston, MA 02118 USA
- />VA Boston Healthcare System, Boston, MA 02130 USA
| | - Yu Jin Hwang
- />WCU Neurocytomics Group, Department of Biomedical Sciences, Seoul National University Graduate School, Seoul, 110-799 South Korea
| | - Ki Yoon Kim
- />WCU Neurocytomics Group, Department of Biomedical Sciences, Seoul National University Graduate School, Seoul, 110-799 South Korea
| | - Neil W. Kowall
- />Boston University Alzheimer’s Disease Center and Department of Neurology, Boston University School of Medicine, Boston, MA 02118 USA
- />VA Boston Healthcare System, Boston, MA 02130 USA
| | - Hoon Ryu
- />Boston University Alzheimer’s Disease Center and Department of Neurology, Boston University School of Medicine, Boston, MA 02118 USA
- />VA Boston Healthcare System, Boston, MA 02130 USA
- />WCU Neurocytomics Group, Department of Biomedical Sciences, Seoul National University Graduate School, Seoul, 110-799 South Korea
| |
Collapse
|
32
|
Choi WI, Jeon BN, Yoon JH, Koh DI, Kim MH, Yu MY, Lee KM, Kim Y, Kim K, Hur SS, Lee CE, Kim KS, Hur MW. The proto-oncoprotein FBI-1 interacts with MBD3 to recruit the Mi-2/NuRD-HDAC complex and BCoR and to silence p21WAF/CDKN1A by DNA methylation. Nucleic Acids Res 2013; 41:6403-20. [PMID: 23658227 PMCID: PMC3711425 DOI: 10.1093/nar/gkt359] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
The tumour-suppressor gene CDKN1A (encoding p21Waf/Cip1) is thought to be epigenetically repressed in cancer cells. FBI-1 (ZBTB7A) is a proto-oncogenic transcription factor repressing the alternative reading frame and p21WAF/CDKN1A genes of the p53 pathway. FBI-1 interacts directly with MBD3 (methyl-CpG–binding domain protein 3) in the nucleus. We demonstrated that FBI-1 binds both non-methylated and methylated DNA and that MBD3 is recruited to the CDKN1A promoter through its interaction with FBI-1, where it enhances transcriptional repression by FBI-1. FBI-1 also interacts with the co-repressors nuclear receptor corepressor (NCoR), silencing mediator for retinoid and thyroid receptors (SMRT) and BCL-6 corepressor (BCoR) to repress transcription. MBD3 regulates a molecular interaction between the co-repressor and FBI-1. MBD3 decreases the interaction between FBI-1 and NCoR/SMRT but increases the interaction between FBI-1 and BCoR. Because MBD3 is a subunit of the Mi-2 autoantigen (Mi-2)/nucleosome remodelling and histone deacetylase (NuRD)-HDAC complex, FBI-1 recruits the Mi-2/NuRD-HDAC complex via MBD3. BCoR interacts with the Mi-2/NuRD-HDAC complex, DNMTs and HP1. MBD3 and BCoR play a significant role in the recruitment of the Mi-2/NuRD-HDAC complex– and the NuRD complex–associated proteins, DNMTs and HP. By recruiting DNMTs and HP1, Mi-2/NuRD-HDAC complex appears to play key roles in epigenetic repression of CDKN1A by DNA methylation.
Collapse
Affiliation(s)
- Won-Il Choi
- Department of Biochemistry and Molecular Biology, BK21 Project for Medical Science, Severance Biomedical Research Institute, Yonsei University School of Medicine, 50 Yonsei-Ro, SeoDaeMoon-Gu, Seoul, 120-752, Korea
| | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
33
|
BIK (NBK) is a mediator of the sensitivity of Fanconi anaemia group C lymphoblastoid cell lines to interstrand DNA cross-linking agents. Biochem J 2013; 448:153-63. [PMID: 22873408 DOI: 10.1042/bj20120327] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
FA (Fanconi anaemia) is a rare hereditary disorder characterized by congenital malformations, progressive bone marrow failure and an extraordinary predisposition to develop cancer. At present, 15 genes have been related to this condition and mutations of them have also been found in different types of cancer. Bone marrow failure threatens the life of FA patients during the first decade of their life, but the mechanisms underlying this process are not completely understood. In the present study we investigate a possible imbalance between the expression of pro- and anti-apoptotic proteins as a cause for the hypersensitivity of FANCC (FA, complementation group C)-deficient cells to genotoxic stress. We found a BIK (Bcl-2 interacting killer) over-expression in lymphoblastoid cell lines derived from FA-C patients when compared with their phenotypically corrected counterparts. This overexpression has a transcriptional basis since the regulatory region of the gene shows higher activity in FANCC-deficient cells. We demonstrate the involvement of BIK in the sensitivity of FA-C lymphoblasts to interstrand DNA cross-linking agents as it is induced by these drugs and interference of its expression in these cells preserves their viability and reduces apoptosis. We investigate the mechanism of BIK overexpression in FANCC-deficient cells by analysing the activity of many different signalling pathways in these cells. Finally, we provide evidence of a previously undescribed indirect epigenetic regulation of BIK in FA-C lymphoblasts mediated by ΔNp73, an isoform of p73 lacking its transactivation domain that activates BIK through a proximal element in its promoter.
Collapse
|
34
|
Abstract
One of the most exciting discoveries in the learning and memory field in the past two decades is the observation that active regulation of gene expression is necessary for experience to trigger lasting functional and behavioral change, in a wide variety of species, including humans. Thus, as opposed to the traditional view of 'nature' (genes) being separate from 'nurture' (environment and experience), it is now clear that experience actively drives alterations in central nervous system (CNS) gene expression in an ongoing fashion, and that the resulting transcriptional changes are necessary for experience to trigger altered long-term behavior. In parallel over the past decade, epigenetic mechanisms, including regulation of chromatin structure and DNA methylation, have been shown to be potent regulators of gene transcription in the CNS. In this review, we describe data supporting the hypothesis that epigenetic molecular mechanisms, especially DNA methylation and demethylation, drive long-term behavioral change through active regulation of gene transcription in the CNS. Specifically, we propose that epigenetic molecular mechanisms underlie the formation and stabilization of context- and cue-triggered fear conditioning based in the hippocampus and amygdala, a conclusion reached in a wide variety of studies using laboratory animals. Given the relevance of cued and contextual fear conditioning to post-traumatic stress, by extension we propose that these mechanisms may contribute to post-traumatic stress disorder (PTSD) in humans. Moreover, we speculate that epigenetically based pharmacotherapy may provide a new avenue of drug treatment for PTSD-related cognitive and behavioral function.
Collapse
Affiliation(s)
- Iva B Zovkic
- Department of Neurobiology, Evelyn F. McKnight Brain Institute, University of Alabama, Birmingham, AL, USA
| | - J David Sweatt
- Department of Neurobiology, Evelyn F. McKnight Brain Institute, University of Alabama, Birmingham, AL, USA,Department of Neurobiology, Evelyn F. McKnight Brain Institute, University of Alabama at Birmingham, 1010 Shelby Building, 1825 University Boulevard, Birmingham, AL 35294-2182, USA, Tel: +205 975 5196, Fax: +205 934 6571, E-mail:
| |
Collapse
|
35
|
Grayson DR, Guidotti A. The dynamics of DNA methylation in schizophrenia and related psychiatric disorders. Neuropsychopharmacology 2013; 38:138-66. [PMID: 22948975 PMCID: PMC3521968 DOI: 10.1038/npp.2012.125] [Citation(s) in RCA: 196] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/01/2012] [Revised: 05/08/2012] [Accepted: 05/09/2012] [Indexed: 02/06/2023]
Abstract
Major psychiatric disorders such as schizophrenia (SZ) and bipolar disorder (BP) with psychosis (BP+) express a complex symptomatology characterized by positive symptoms, negative symptoms, and cognitive impairment. Postmortem studies of human SZ and BP+ brains show considerable alterations in the transcriptome of a variety of cortical structures, including multiple mRNAs that are downregulated in both inhibitory GABAergic and excitatory pyramidal neurons compared with non-psychiatric subjects (NPS). Several reports show increased expression of DNA methyltransferases in telencephalic GABAergic neurons. Accumulating evidence suggests a critical role for altered DNA methylation processes in the pathogenesis of SZ and related psychiatric disorders. The establishment and maintenance of CpG site methylation is essential during central nervous system differentiation and this methylation has been implicated in synaptic plasticity, learning, and memory. Atypical hypermethylation of candidate gene promoters expressed in GABAergic neurons is associated with transcriptional downregulation of the corresponding mRNAs, including glutamic acid decarboxylase 67 (GAD67) and reelin (RELN). Recent reports indicate that the methylation status of promoter proximal CpG dinucleotides is in a dynamic balance between DNA methylation and DNA hydroxymethylation. Hydroxymethylation and subsequent DNA demethylation is more complex and involves additional proteins downstream of 5-hydroxymethylcytosine, including members of the base excision repair (BER) pathway. Recent advances in our understanding of altered CpG methylation, hydroxymethylation, and active DNA demethylation provide a framework for the identification of new targets, which may be exploited for the pharmacological intervention of the psychosis associated with SZ and possibly BP+.
Collapse
Affiliation(s)
- Dennis R Grayson
- The Psychiatric Institute, Department of Psychiatry, College of Medicine, University of Illinois at Chicago, Chicago, IL 60612, USA.
| | | |
Collapse
|
36
|
D'Costa ZJ, Jolly C, Androphy EJ, Mercer A, Matthews CM, Hibma MH. Transcriptional repression of E-cadherin by human papillomavirus type 16 E6. PLoS One 2012; 7:e48954. [PMID: 23189137 PMCID: PMC3506579 DOI: 10.1371/journal.pone.0048954] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2012] [Accepted: 10/03/2012] [Indexed: 02/01/2023] Open
Abstract
There is increasing evidence supporting DNA virus regulation of the cell adhesion and tumour suppressor protein, E-cadherin. We previously reported that loss of E-cadherin in human papillomavirus (HPV) type 16-infected epidermis is contributed to by the major viral proto-oncogene E6 and is associated with reduced Langerhans cells density, potentially regulating the immune response. The focus of this study is determining how the HPV16 E6 protein mediates E-cadherin repression. We found that the E-cadherin promoter is repressed in cells expressing E6, resulting in fewer E-cadherin transcripts. On exploring the mechanism for this, repression by increased histone deacetylase activity or by increased binding of trans-repressors to the E-cadherin promoter Epal element was discounted. In contrast, DNA methyltransferase (DNMT) activity was increased in E6 expressing cells. Upon inhibiting DNMT activity using 5-Aza-2'-deoxycytidine, E-cadherin transcription was restored in the presence of HPV16 E6. The E-cadherin promoter was not directly methylated, however a mutational analysis showed general promoter repression and reduced binding of the transactivators Sp1 and AML1 and the repressor Slug. Expression of E7 with E6 resulted in a further reduction in surface E-cadherin levels. This is the first report of HPV16 E6-mediated transcriptional repression of this adhesion molecule and tumour suppressor protein.
Collapse
Affiliation(s)
- Zarina J. D'Costa
- Virus Research Unit, Department of Microbiology and Immunology, University of Otago, Dunedin, New Zealand
| | - Carol Jolly
- Department of Dermatology, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
| | - Elliot J. Androphy
- Department of Dermatology, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
| | - Andrew Mercer
- Virus Research Unit, Department of Microbiology and Immunology, University of Otago, Dunedin, New Zealand
| | - Charles M. Matthews
- Virus Research Unit, Department of Microbiology and Immunology, University of Otago, Dunedin, New Zealand
| | - Merilyn H. Hibma
- Virus Research Unit, Department of Microbiology and Immunology, University of Otago, Dunedin, New Zealand
| |
Collapse
|
37
|
Abstract
Mammalian DNA methyltransferase 1 (DNMT1) is essential during early embryo development. Consistent with its key role in embryogenesis, depletion of this protein in adult somatic cells promotes severe cellular dysfunctions and cell death. DNMT1 contains a highly evolutionary conserved C-terminal catalytic DNA methyltransferase domain that is thought to be the responsible for the maintenance of CpG methylation patterns in the genome. DNMT1 has also a large N-terminal region with different functional protein-protein and protein-DNA binding domains. The multi-domain N-terminal region and the abundant molecular binding patterns suggest potential non-catalytic functions for DNMT1. However, this hypothesis remains controversial and conflicting results can be found in the literature. Here, recent results presenting a functional role for DNMT1 independent of its catalytic domain are discussed.
Collapse
Affiliation(s)
- Jesús Espada
- Departamento de Bioquímica, Instituto de Investigaciones Biomédicas "Alberto Sols" CSIC-UAM, Universidad Autónoma de Madrid, Spain.
| |
Collapse
|
38
|
Saferali A, Moussette S, Chan D, Trasler J, Chen T, Rozen R, Naumova AK. DNA methyltransferase 1 (Dnmt1) mutation affects Snrpn imprinting in the mouse male germ line. Genome 2012; 55:673-82. [PMID: 22967183 DOI: 10.1139/g2012-056] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
DNA methylation and DNA methyltransferases are essential for spermatogenesis. Mutations in the DNA methyltransferase Dnmt1 gene exert a paternal effect on epigenetic states and phenotypes of offspring, suggesting that DNMT1 is important for the epigenetic remodeling of the genome that takes place during spermatogenesis. However, the specific role of DNMT1 in spermatogenesis and the establishment of genomic imprints in the male germ line remains elusive. To further characterize the effect of DNMT1 deficiency on the resetting of methylation imprints during spermatogenesis, we analyzed the methylation profiles of imprinted regions in the spermatozoa of mice that were heterozygous for a Dnmt1 loss-of-function mutation. The mutation did not affect the H19 or IG differentially methylated regions (DMRs) that are usually highly methylated but led to a partial hypermethylation of the Snrpn DMR, a region that should normally be unmethylated in mature spermatozoa. This defect does not appear in mouse models with mutations in Dnmt3a and Mthfr genes and, therefore, it is specific for the Dnmt1 gene and is suggestive of a role of DNMT1 in imprint resetting or maintenance in the male germ line.
Collapse
Affiliation(s)
- Aabida Saferali
- Department of Human Genetics, McGill University, Montréal, QC H3A 1B1, Canada
| | | | | | | | | | | | | |
Collapse
|
39
|
Yun J, Song SH, Park J, Kim HP, Yoon YK, Lee KH, Han SW, Oh DY, Im SA, Bang YJ, Kim TY. Gene silencing of EREG mediated by DNA methylation and histone modification in human gastric cancers. J Transl Med 2012; 92:1033-44. [PMID: 22508389 DOI: 10.1038/labinvest.2012.61] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Epiregulin (EREG) induces cell growth by binding to the epidermal growth factor receptor (EGFR). Expression of EREG affects sensitivity to cetuximab a chimeric monoclonal antibody that inhibits the EGFR signaling pathway. The mechanism through which EREG is regulated is largely unknown, but a methyl-array study previously performed by our group revealed that EREG is methylated in gastric cancer cells. In this study, we found that EREG gene expression was low in 7 out of 11 gastric cancer cells and this downregulation was mediated by aberrant CpG methylation of the EREG promoter. Treatment with 5-aza-CdR restored EREG expression and demethylated CpG sites in the EREG promoter. Compared with DNA methyltransferase 1 (DNMT1), knock-down of DNA methyltransferase 3b (DNMT3b) significantly increased the expression of EREG and led to the demethylation of specific CpG sites in the EREG promoter, suggesting that DNMT3b primarily regulates CpG methylation and silencing of the EREG gene. EREG methylation was observed in 30% (4/13) of human primary gastric tumor tissues we evaluated. In addition to DNA methylation, results from a chromatin immunoprecipitation assay demonstrated that transcriptional levels of EREG were associated with the enrichment of active histone marks (H3K4me3 and AcH3) and of a repressive mark (H3K27me2). Treatment with 5-aza-CdR dynamically increased the low occupancy of H3K4me3 and AcH3, while decreasing the high enrichment of H3K27me2, indicating that dynamic histone modifications contribute to EREG regulation in addition to DNA methylation. Finally, the combination of 5-aza-CdR and cetuximab exerted a synergistic anti-proliferative effect on gastric cancer cells. Taken together, the results of our study showed for the first time that EREG is epigenetically silenced in gastric cancer cells by aberrant DNA methylation and histone modification.
Collapse
MESH Headings
- Animals
- Antibodies, Monoclonal/administration & dosage
- Antibodies, Monoclonal, Humanized
- Azacitidine/administration & dosage
- Azacitidine/analogs & derivatives
- Azacitidine/pharmacology
- Cell Line, Tumor
- Cetuximab
- CpG Islands
- DNA (Cytosine-5-)-Methyltransferase 1
- DNA (Cytosine-5-)-Methyltransferases/antagonists & inhibitors
- DNA (Cytosine-5-)-Methyltransferases/genetics
- DNA Methylation
- Decitabine
- Epidermal Growth Factor/antagonists & inhibitors
- Epidermal Growth Factor/genetics
- Epigenesis, Genetic/drug effects
- Epiregulin
- ErbB Receptors/metabolism
- Gene Knockdown Techniques
- Gene Silencing
- Histones/genetics
- Histones/metabolism
- Humans
- Mice
- Mice, Inbred BALB C
- Mice, Nude
- Promoter Regions, Genetic
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- RNA, Neoplasm/genetics
- RNA, Neoplasm/metabolism
- RNA, Small Interfering/genetics
- Stomach Neoplasms/drug therapy
- Stomach Neoplasms/genetics
- Stomach Neoplasms/metabolism
- Xenograft Model Antitumor Assays
- DNA Methyltransferase 3B
Collapse
Affiliation(s)
- Jiyeon Yun
- Cancer Research Institute, Seoul National University College of Medicine, South Korea
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
40
|
Hagemann S, Kuck D, Stresemann C, Prinz F, Brueckner B, Mund C, Mumberg D, Sommer A. Antiproliferative effects of DNA methyltransferase 3B depletion are not associated with DNA demethylation. PLoS One 2012; 7:e36125. [PMID: 22563479 PMCID: PMC3341356 DOI: 10.1371/journal.pone.0036125] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2012] [Accepted: 03/26/2012] [Indexed: 12/20/2022] Open
Abstract
Silencing of genes by hypermethylation contributes to cancer progression and has been shown to occur with increased frequency at specific genomic loci. However, the precise mechanisms underlying the establishment and maintenance of aberrant methylation marks are still elusive. The de novo DNA methyltransferase 3B (DNMT3B) has been suggested to play an important role in the generation of cancer-specific methylation patterns. Previous studies have shown that a reduction of DNMT3B protein levels induces antiproliferative effects in cancer cells that were attributed to the demethylation and reactivation of tumor suppressor genes. However, methylation changes have not been analyzed in detail yet. Using RNA interference we reduced DNMT3B protein levels in colon cancer cell lines. Our results confirm that depletion of DNMT3B specifically reduced the proliferation rate of DNMT3B-overexpressing colon cancer cell lines. However, genome-scale DNA methylation profiling failed to reveal methylation changes at putative DNMT3B target genes, even in the complete absence of DNMT3B. These results show that DNMT3B is dispensable for the maintenance of aberrant DNA methylation patterns in human colon cancer cells and they have important implications for the development of targeted DNA methyltransferase inhibitors as epigenetic cancer drugs.
Collapse
Affiliation(s)
- Sabine Hagemann
- Division of Epigenetics, DKFZ-ZMBH Alliance, German Cancer Research Center, Heidelberg, Germany
| | - Dirk Kuck
- Division of Epigenetics, DKFZ-ZMBH Alliance, German Cancer Research Center, Heidelberg, Germany
- Global Drug Discovery, Bayer Healthcare Pharmaceuticals, Berlin, Germany
| | - Carlo Stresemann
- Global Drug Discovery, Bayer Healthcare Pharmaceuticals, Berlin, Germany
| | - Florian Prinz
- Global Drug Discovery, Bayer Healthcare Pharmaceuticals, Berlin, Germany
| | - Bodo Brueckner
- Division of Epigenetics, DKFZ-ZMBH Alliance, German Cancer Research Center, Heidelberg, Germany
| | - Cora Mund
- Global Drug Discovery, Bayer Healthcare Pharmaceuticals, Berlin, Germany
| | - Dominik Mumberg
- Global Drug Discovery, Bayer Healthcare Pharmaceuticals, Berlin, Germany
| | - Anette Sommer
- Global Drug Discovery, Bayer Healthcare Pharmaceuticals, Berlin, Germany
| |
Collapse
|
41
|
Repression of androgen receptor transcription through the E2F1/DNMT1 axis. PLoS One 2011; 6:e25187. [PMID: 21966451 PMCID: PMC3180375 DOI: 10.1371/journal.pone.0025187] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2011] [Accepted: 08/26/2011] [Indexed: 12/04/2022] Open
Abstract
Although androgen receptor (AR) function has been extensively studied, regulation of the AR gene itself has been much less characterized. In this study, we observed a dramatic reduction in the expression of androgen receptor mRNA and protein in hyperproliferative prostate epithelium of keratin 5 promoter driven E2F1 transgenic mice. To confirm an inhibitory function for E2F1 on AR transcription, we showed that E2F1 inhibited the transcription of endogenous AR mRNA, subsequent AR protein, and AR promoter activity in both human and mouse epithelial cells. E2F1 also inhibited androgen-stimulated activation of two AR target gene promoters. To elucidate the molecular mechanism of E2F-mediated inhibition of AR, we evaluated the effects of two functional E2F1 mutants on AR promoter activity and found that the transactivation domain appears to mediate E2F1 repression of the AR promoter. Because DNMT1 is a functional intermediate of E2F1 we examined DNMT1 function in AR repression. Repression of endogenous AR in normal human prostate epithelial cells was relieved by DNMT1 shRNA knock down. DNMT1 was shown to be physically associated within the AR minimal promoter located 22 bps from the transcription start site; however, methylation remained unchanged at the promoter regardless of DNMT1 expression. Taken together, our results suggest that DNMT1 operates either as a functional intermediary or in cooperation with E2F1 inhibiting AR gene expression in a methylation independent manner.
Collapse
|
42
|
Espada J, Peinado H, Lopez-Serra L, Setién F, Lopez-Serra P, Portela A, Renart J, Carrasco E, Calvo M, Juarranz A, Cano A, Esteller M. Regulation of SNAIL1 and E-cadherin function by DNMT1 in a DNA methylation-independent context. Nucleic Acids Res 2011; 39:9194-205. [PMID: 21846773 PMCID: PMC3241660 DOI: 10.1093/nar/gkr658] [Citation(s) in RCA: 68] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Mammalian DNA methyltransferase 1 (DNMT1) is essential for maintaining DNA methylation patterns after cell division. Disruption of DNMT1 catalytic activity results in whole genome cytosine demethylation of CpG dinucleotides, promoting severe dysfunctions in somatic cells and during embryonic development. While these observations indicate that DNMT1-dependent DNA methylation is required for proper cell function, the possibility that DNMT1 has a role independent of its catalytic activity is a matter of controversy. Here, we provide evidence that DNMT1 can support cell functions that do not require the C-terminal catalytic domain. We report that PCNA and DMAP1 domains in the N-terminal region of DNMT1 are sufficient to modulate E-cadherin expression in the absence of noticeable changes in DNA methylation patterns in the gene promoters involved. Changes in E-cadherin expression are directly associated with regulation of β-catenin-dependent transcription. Present evidence suggests that the DNMT1 acts on E-cadherin expression through its direct interaction with the E-cadherin transcriptional repressor SNAIL1.
Collapse
Affiliation(s)
- Jesús Espada
- Instituto de Investigaciones Biomédicas Alberto Sols, CSIC-UAM, Instituto de Investigación Hospital Universitario La Paz, Madrid, Spain
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
43
|
Stefanska B, Huang J, Bhattacharyya B, Suderman M, Hallett M, Han ZG, Szyf M. Definition of the landscape of promoter DNA hypomethylation in liver cancer. Cancer Res 2011; 71:5891-903. [PMID: 21747116 DOI: 10.1158/0008-5472.can-10-3823] [Citation(s) in RCA: 148] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
We use hepatic cellular carcinoma (HCC), one of the most common human cancers, as a model to delineate the landscape of promoter hypomethylation in cancer. Using a combination of methylated DNA immunoprecipitation and hybridization with comprehensive promoter arrays, we have identified approximately 3,700 promoters that are hypomethylated in tumor samples. The hypomethylated promoters appeared in clusters across the genome suggesting that a high-level organization underlies the epigenomic changes in cancer. In normal liver, most hypomethylated promoters showed an intermediate level of methylation and expression, however, high-CpG dense promoters showed the most profound increase in gene expression. The demethylated genes are mainly involved in cell growth, cell adhesion and communication, signal transduction, mobility, and invasion; functions that are essential for cancer progression and metastasis. The DNA methylation inhibitor, 5-aza-2'-deoxycytidine, activated several of the genes that are demethylated and induced in tumors, supporting a causal role for demethylation in activation of these genes. Previous studies suggested that MBD2 was involved in demethylation of specific human breast and prostate cancer genes. Whereas MBD2 depletion in normal liver cells had little or no effect, we found that its depletion in human HCC and adenocarcinoma cells resulted in suppression of cell growth, anchorage-independent growth and invasiveness as well as an increase in promoter methylation and silencing of several of the genes that are hypomethylated in tumors. Taken together, the findings define the potential functional role of hypomethylation in cancer.
Collapse
Affiliation(s)
- Barbara Stefanska
- Department of Pharmacology and Therapeutics, McGill Centre for Bioinformatics, Montreal, Canada
| | | | | | | | | | | | | |
Collapse
|
44
|
Xiang G, Zhenkun F, Shuang C, Jie Z, Hua Z, Wei J, Da P, Dianjun L. Association of DNMT1 Gene Polymorphisms in Exons With Sporadic Infiltrating Ductal Breast Carcinoma Among Chinese Han Women in the Heilongjiang Province. Clin Breast Cancer 2010; 10:373-7. [DOI: 10.3816/cbc.2010.n.049] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
|
45
|
Szyf M. DNA methylation and demethylation probed by small molecules. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2010; 1799:750-9. [DOI: 10.1016/j.bbagrm.2010.09.002] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/02/2010] [Revised: 09/05/2010] [Accepted: 09/08/2010] [Indexed: 10/19/2022]
|
46
|
Kurita S, Higuchi H, Saito Y, Nakamoto N, Takaishi H, Tada S, Saito H, Gores GJ, Hibi T. DNMT1 and DNMT3b silencing sensitizes human hepatoma cells to TRAIL-mediated apoptosis via up-regulation of TRAIL-R2/DR5 and caspase-8. Cancer Sci 2010; 101:1431-9. [PMID: 20398055 PMCID: PMC11158615 DOI: 10.1111/j.1349-7006.2010.01565.x] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2009] [Revised: 02/09/2010] [Accepted: 02/28/2010] [Indexed: 12/31/2022] Open
Abstract
DNA methylation plays a critical role in chromatin remodeling and gene expression. DNA methyltransferases (DNMTs) are hypothesized to mediate cellular DNA methylation status and gene expression during mammalian development and in malignant diseases. In this study, we examined the role of DNA methyltransferase 1 (DNMT1) and DNMT3b in cell proliferation and survival of hepatocellular carcinoma (HCC) cells. Gene silencing of both DNMT1 and DNMT3b by targeted siRNA knockdown reduces cell proliferation and sensitizes the cells to tumor necrosis factor-related apoptosis-inducing ligand (TRAIL)-mediated cell death. The proapoptotic protein caspase-8 demonstrated promoter hypermethylation in HCC cells and was up-regulated by knockdown of DNMT1 and DNMT3b both at mRNA and protein levels. In addition, death receptor TRAIL-R2/DR5 (TRAIL receptor 2/death receptor 5) did not exhibit promoter hypermethylation in HCC cells but was also up-regulated by knockdown of DNMT1 and DNMT3b both at mRNA and protein levels. Consistent with this observation, the combined transfection of DNMT1-siRNA plus DNMT3b-siRNA enhanced formation of the TRAIL-death-inducing signaling complex formation in HCC cells. In conclusion, our data suggest that DNA methylation of specific genomic regions maintained by DNMT1 and DNMT3b plays a critical role in survival of HCC cells, and a simultaneous knockdown of both DNMT1 and DNMT3b may be a novel anticancer strategy for the treatment of HCC.
Collapse
Affiliation(s)
- Satoshi Kurita
- Department of Internal Medicine, School of Medicine, Keio University, Tokyo, Japan.
| | | | | | | | | | | | | | | | | |
Collapse
|
47
|
Lin RK, Hsieh YS, Lin P, Hsu HS, Chen CY, Tang YA, Lee CF, Wang YC. The tobacco-specific carcinogen NNK induces DNA methyltransferase 1 accumulation and tumor suppressor gene hypermethylation in mice and lung cancer patients. J Clin Invest 2010; 120:521-32. [PMID: 20093774 DOI: 10.1172/jci40706] [Citation(s) in RCA: 155] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2009] [Accepted: 12/02/2009] [Indexed: 12/28/2022] Open
Abstract
DNA methyltransferase 1 (DNMT1) catalyzes DNA methylation and is overexpressed in many human diseases, including cancer. The tobacco-specific carcinogen NNK also induces DNA methylation. However, the role of DNMT1-mediated methylation in tobacco carcinogenesis remains unclear. Here we used human and mouse lung cancer samples and cell lines to determine a mechanism whereby NNK induced DNMT1 expression and activity. We determined that in a human lung cell line, glycogen synthase kinase 3beta (GSK3beta) phosphorylated DNMT1 to recruit beta-transducin repeat-containing protein (betaTrCP), resulting in DNMT1 degradation, and that NNK activated AKT, inhibiting GSK3beta function and thereby attenuating DNMT1 degradation. NNK also induced betaTrCP translocation to the cytoplasm via the heterogeneous nuclear ribonucleoprotein U (hnRNP-U) shuttling protein, resulting in DNMT1 nuclear accumulation and hypermethylation of the promoters of tumor suppressor genes. Fluorescence immunohistochemistry (IHC) of lung adenomas from NNK-treated mice and tumors from lung cancer patients that were smokers were characterized by disruption of the DNMT1/betaTrCP interaction and DNMT1 nuclear accumulation. Importantly, DNMT1 overexpression in lung cancer patients who smoked continuously correlated with poor prognosis. We believe that the NNK-induced DNMT1 accumulation and subsequent hypermethylation of the promoter of tumor suppressor genes may lead to tumorigenesis and poor prognosis and provide an important link between tobacco smoking and lung cancer. Furthermore, this mechanism may also be involved in other smoking-related human diseases.
Collapse
Affiliation(s)
- Ruo-Kai Lin
- Department of Pharmacology, National Cheng Kung University, Tainan, Republic of China
| | | | | | | | | | | | | | | |
Collapse
|
48
|
BIK, the founding member of the BH3-only family proteins: mechanisms of cell death and role in cancer and pathogenic processes. Oncogene 2009; 27 Suppl 1:S20-9. [PMID: 19641504 DOI: 10.1038/onc.2009.40] [Citation(s) in RCA: 79] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
BIK is the founding member of the BH3-only family pro-apoptotic proteins. BIK is predominantly localized in the ER and induces apoptosis through the mitochondrial pathway by mobilizing calcium from the ER to the mitochondria and remodeling the mitochondrial cristae. BIK-mediated apoptosis is mediated by selective activation of BAX. BIK also induces non-apoptotic cell death in certain cell types by unknown mechanisms. BIK is non-essential for animal development, but appears to be functionally redundant for certain developmental functions with BIM. BIK is implicated in the selection of mature B cells in humans. BIK is a pro-apoptotic tumor suppressor in several human tissues and its expression in cancers is prevented by chromosomal deletions encompassing the Bik locus or by epigenetic silencing. BIK appears to be a critical effector in apoptosis induced by toxins, cytokines and virus infection. Several anti-cancer drugs transcriptionally activate Bik gene expression through transcriptional pathways dependent on factors such as E2F and p53 or by removal of epigenetic marks on the chromatin. BIK appears to be a prominent target for anti-cancer drugs that inhibit proteasomal functions. BIK has also been used as a therapeutic molecule in gene therapy-based approaches to treat difficult cancers.
Collapse
|
49
|
Foltz G, Yoon JG, Lee H, Ryken TC, Sibenaller Z, Ehrich M, Hood L, Madan A. DNA methyltransferase-mediated transcriptional silencing in malignant glioma: a combined whole-genome microarray and promoter array analysis. Oncogene 2009; 28:2667-77. [PMID: 19465937 DOI: 10.1038/onc.2009.122] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2008] [Revised: 03/06/2009] [Accepted: 04/15/2009] [Indexed: 01/11/2023]
Abstract
Epigenetic inactivation of tumor suppressor genes is a common feature in human cancer. Promoter hypermethylation and histone deacetylation are reversible epigenetic mechanisms associated with transcriptional regulation. DNA methyltransferases (DNMT1 and DNMT3b) regulate and maintain promoter methylation and are overexpressed in human cancer. We performed whole-genome microarray analysis to identify genes with altered expression after RNAi-induced suppression of DNMT in a glioblastoma multiforme (GBM) cell line. We then identified genes with both decreased expression and evidence of promoter CpG island hypermethylation in GBM tissue samples using a combined whole-genome microarray transcriptome analysis in conjunction with a promoter array analysis after DNA immunoprecipitation with anti-5-methylcytidine. DNMT1 and 3b knockdown resulted in the restored expression of 308 genes that also contained promoter region hypermethylation. Of these, 43 were also found to be downregulated in GBM tissue samples. Three downregulated genes with hypermethylated promoters and restored expression in response to acute DNMT suppression were assayed for methylation changes using bisulfite sequence analysis of the promoter region after chronic DNMT suppression. Restoration of gene expression was not associated with changes in promoter region methylation, but rather with changes in histone methylation and chromatin conformation. Two of the identified genes exhibited growth suppressive activity in in vitro assays. Combining targeted genetic manipulations with comprehensive genomic and expression analyses provides a potentially powerful new approach for identifying epigenetically regulated genes in GBM.
Collapse
Affiliation(s)
- G Foltz
- Center for Advanced Brain Tumor Treatment, Swedish Neuroscience Institute, Seattle, WA 98122, USA.
| | | | | | | | | | | | | | | |
Collapse
|
50
|
Anderson RM, Bosch JA, Goll MG, Hesselson D, Dong PDS, Shin D, Chi NC, Shin CH, Schlegel A, Halpern M, Stainier DYR. Loss of Dnmt1 catalytic activity reveals multiple roles for DNA methylation during pancreas development and regeneration. Dev Biol 2009; 334:213-23. [PMID: 19631206 DOI: 10.1016/j.ydbio.2009.07.017] [Citation(s) in RCA: 120] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2009] [Revised: 07/07/2009] [Accepted: 07/15/2009] [Indexed: 02/02/2023]
Abstract
Developmental mechanisms regulating gene expression and the stable acquisition of cell fate direct cytodifferentiation during organogenesis. Moreover, it is likely that such mechanisms could be exploited to repair or regenerate damaged organs. DNA methyltransferases (Dnmts) are enzymes critical for epigenetic regulation, and are used in concert with histone methylation and acetylation to regulate gene expression and maintain genomic integrity and chromosome structure. We carried out two forward genetic screens for regulators of endodermal organ development. In the first, we screened for altered morphology of developing digestive organs, while in the second we screed for the lack of terminally differentiated cell types in the pancreas and liver. From these screens, we identified two mutant alleles of zebrafish dnmt1. Both lesions are predicted to eliminate dnmt1 function; one is a missense mutation in the catalytic domain and the other is a nonsense mutation that eliminates the catalytic domain. In zebrafish dnmt1 mutants, the pancreas and liver form normally, but begin to degenerate after 84 h post fertilization (hpf). Acinar cells are nearly abolished through apoptosis by 100 hpf, though neither DNA replication, nor entry into mitosis is halted in the absence of detectable Dnmt1. However, endocrine cells and ducts are largely spared. Surprisingly, dnmt1 mutants and dnmt1 morpholino-injected larvae show increased capacity for pancreatic beta cell regeneration in an inducible model of pancreatic beta cell ablation. Thus, our data suggest that Dnmt1 is dispensable for pancreatic duct or endocrine cell formation, but not for acinar cell survival. In addition, Dnmt1 may influence the differentiation of pancreatic beta cell progenitors or the reprogramming of cells toward the pancreatic beta cell fate.
Collapse
Affiliation(s)
- Ryan M Anderson
- Department of Biochemistry and Biophysics, Programs in Developmental Biology, Genetics, and Human Genetics, Diabetes Center, and Liver Center, University of California, San Francisco, San Francisco, CA 94158-2324, USA. (
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|