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Zhao M, Zhou G, Wang J, Zhang Y, Xue J, Liu J, Xie J, Ren L, Zhou X. MiR-5622-3p inhibits ZCWPW1 to induce apoptosis in silica-exposed mice and spermatocyte cells. Nanotoxicology 2023:1-13. [PMID: 37315217 DOI: 10.1080/17435390.2023.2223632] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2023] [Revised: 04/17/2023] [Accepted: 05/22/2023] [Indexed: 06/16/2023]
Abstract
Silica nanoparticles (SiNPs) could cause damage to spermatogenesis, and microRNAs were reported to be associated with male reproduction. This research was designed to explore the toxic impacts of SiNPs induced in male reproduction through miR-5622-3p. In vivo, 60 mice were randomized into the control group and SiNPs group, in which they were exposed to SiNPs for 35 days and then recovered for 15 days. In vitro, 4 groups were set: control group, SiNPs group, SiNPs + miR-5622-3p inhibitor group, and SiNPs + miR-5622-3p inhibitor negative control (NC) group. Our research indicated SiNPs caused the apoptosis of spermatogenic cells, increased level of γ-H2AX, raised the expressions of RAD51, DMC1, 53BP1, and LC8 which were DNA damage repair relative factors, and upregulated Cleaved-Caspase-9 and Cleaved-Caspase-3 levels. Furthermore, SiNPs also elevated the expression of miR-5622-3p but downregulated the level of ZCWPW1. However, miR-5622-3p inhibitor reduced the level of miR-5622-3p, increased the level of ZCWPW1, relieved DNA damage, and depressed the activation of apoptosis pathway, thus, alleviating spermatogenic cells apoptosis caused by SiNPs. The above-mentioned results indicated that SiNPs induced DNA damage resulting in activating of DNA damage response. Meanwhile, SiNPs raised the level of miR-5622-3p targeting inhibited expression of ZCWPW1 to suppress the repair process, possibly making DNA damage so severe that leading to the failure of DNA damage repair, finally inducing the apoptosis of spermatogenic cells.
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Affiliation(s)
- Moxuan Zhao
- Department of Toxicology and Hygienic Chemistry, School of Public Health, Capital Medical University, Beijing, China
- Beijing Key Laboratory of Environmental Toxicology, Capital Medical University, Beijing, China
| | - Guiqing Zhou
- Department of Toxicology and Hygienic Chemistry, School of Public Health, Capital Medical University, Beijing, China
- Beijing Key Laboratory of Environmental Toxicology, Capital Medical University, Beijing, China
| | - Jingjing Wang
- Department of Laboratory Animal, Capital Medical University, Beijing, China
| | - Yue Zhang
- Department of Toxicology and Hygienic Chemistry, School of Public Health, Capital Medical University, Beijing, China
- Beijing Key Laboratory of Environmental Toxicology, Capital Medical University, Beijing, China
| | - Jinglong Xue
- Department of Toxicology and Hygienic Chemistry, School of Public Health, Capital Medical University, Beijing, China
- Beijing Key Laboratory of Environmental Toxicology, Capital Medical University, Beijing, China
| | - Jianhui Liu
- Central Laboratory, Beijing Obstetrics and Gynecology Hospital, Capital Medical University, Chaoyang, Beijing, China
| | - Junhong Xie
- Department of Toxicology and Hygienic Chemistry, School of Public Health, Capital Medical University, Beijing, China
- Beijing Key Laboratory of Environmental Toxicology, Capital Medical University, Beijing, China
| | - Lihua Ren
- School of Nursing, Peking University, Beijing, China
| | - Xianqing Zhou
- Department of Toxicology and Hygienic Chemistry, School of Public Health, Capital Medical University, Beijing, China
- Beijing Key Laboratory of Environmental Toxicology, Capital Medical University, Beijing, China
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2
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AU-Rich Element RNA Binding Proteins: At the Crossroads of Post-Transcriptional Regulation and Genome Integrity. Int J Mol Sci 2021; 23:ijms23010096. [PMID: 35008519 PMCID: PMC8744917 DOI: 10.3390/ijms23010096] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2021] [Revised: 12/17/2021] [Accepted: 12/18/2021] [Indexed: 12/14/2022] Open
Abstract
Genome integrity must be tightly preserved to ensure cellular survival and to deter the genesis of disease. Endogenous and exogenous stressors that impose threats to genomic stability through DNA damage are counteracted by a tightly regulated DNA damage response (DDR). RNA binding proteins (RBPs) are emerging as regulators and mediators of diverse biological processes. Specifically, RBPs that bind to adenine uridine (AU)-rich elements (AREs) in the 3' untranslated region (UTR) of mRNAs (AU-RBPs) have emerged as key players in regulating the DDR and preserving genome integrity. Here we review eight established AU-RBPs (AUF1, HuR, KHSRP, TIA-1, TIAR, ZFP36, ZFP36L1, ZFP36L2) and their ability to maintain genome integrity through various interactions. We have reviewed canonical roles of AU-RBPs in regulating the fate of mRNA transcripts encoding DDR genes at multiple post-transcriptional levels. We have also attempted to shed light on non-canonical roles of AU-RBPs exploring their post-translational modifications (PTMs) and sub-cellular localization in response to genotoxic stresses by various factors involved in DDR and genome maintenance. Dysfunctional AU-RBPs have been increasingly found to be associated with many human cancers. Further understanding of the roles of AU-RBPS in maintaining genomic integrity may uncover novel therapeutic strategies for cancer.
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Murashko MM, Stasevich EM, Schwartz AM, Kuprash DV, Uvarova AN, Demin DE. The Role of RNA in DNA Breaks, Repair and Chromosomal Rearrangements. Biomolecules 2021; 11:biom11040550. [PMID: 33918762 PMCID: PMC8069526 DOI: 10.3390/biom11040550] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2021] [Revised: 03/31/2021] [Accepted: 04/07/2021] [Indexed: 12/28/2022] Open
Abstract
Incorrect reparation of DNA double-strand breaks (DSB) leading to chromosomal rearrangements is one of oncogenesis's primary causes. Recently published data elucidate the key role of various types of RNA in DSB formation, recognition and repair. With growing interest in RNA biology, increasing RNAs are classified as crucial at the different stages of the main pathways of DSB repair in eukaryotic cells: nonhomologous end joining (NHEJ) and homology-directed repair (HDR). Gene mutations or variation in expression levels of such RNAs can lead to local DNA repair defects, increasing the chromosome aberration frequency. Moreover, it was demonstrated that some RNAs could stimulate long-range chromosomal rearrangements. In this review, we discuss recent evidence demonstrating the role of various RNAs in DSB formation and repair. We also consider how RNA may mediate certain chromosomal rearrangements in a sequence-specific manner.
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Affiliation(s)
- Matvey Mikhailovich Murashko
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, 119991 Moscow, Russia; (M.M.M.); (E.M.S.); (A.M.S.); (D.V.K.); (A.N.U.)
| | - Ekaterina Mikhailovna Stasevich
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, 119991 Moscow, Russia; (M.M.M.); (E.M.S.); (A.M.S.); (D.V.K.); (A.N.U.)
| | - Anton Markovich Schwartz
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, 119991 Moscow, Russia; (M.M.M.); (E.M.S.); (A.M.S.); (D.V.K.); (A.N.U.)
- Moscow Institute of Physics and Technology, Department of Molecular and Biological Physics, 141701 Moscow, Russia
| | - Dmitriy Vladimirovich Kuprash
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, 119991 Moscow, Russia; (M.M.M.); (E.M.S.); (A.M.S.); (D.V.K.); (A.N.U.)
| | - Aksinya Nicolaevna Uvarova
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, 119991 Moscow, Russia; (M.M.M.); (E.M.S.); (A.M.S.); (D.V.K.); (A.N.U.)
| | - Denis Eriksonovich Demin
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, 119991 Moscow, Russia; (M.M.M.); (E.M.S.); (A.M.S.); (D.V.K.); (A.N.U.)
- Correspondence:
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Fan H, Zaman MAU, Chen W, Ali T, Campbell A, Zhang Q, Setu NI, Saxon E, Zahn NM, Benko AM, Arnold LA, Peng X. Assessment of Phenylboronic Acid Nitrogen Mustards as Potent and Selective Drug Candidates for Triple-Negative Breast Cancer. ACS Pharmacol Transl Sci 2021; 4:687-702. [PMID: 33860194 PMCID: PMC8033613 DOI: 10.1021/acsptsci.0c00092] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2020] [Indexed: 12/18/2022]
Abstract
Triple-negative breast cancer (TNBC) has limited treatment options and the worst prognosis among all types of breast cancer. We describe two prodrugs, namely, CWB-20145 (1) and its methyl analogue FAN-NM-CH3 (2) that reduced the size of TNBC-derived tumors. The DNA cross-linking of nitrogen mustard prodrugs 1 and 2 was superior to that of chlorambucil and melphalan once activated in the presence of H2O2. The cellular toxicity of 1 and 2 was demonstrated in seven human cancer cell lines. The TNBC cell line MDA-MB-468 was particularly sensitive toward 1 and 2. Compound 2 was 10 times more cytotoxic than chlorambucil and 16 times more active than melphalan. An evaluation of the gene expression demonstrated an upregulation of the tumor suppressor genes p53 and p21 supporting a transcriptional mechanism of a reduced tumor growth. Pharmacokinetic studies with 1 showed a rapid conversion of the prodrug. The introduction of a methyl group generated 2 with an increased half-life. An in vivo toxicity study in mice demonstrated that both prodrugs were less toxic than chlorambucil. Compounds 1 and 2 reduced tumor growth with an inhibition rate of more than 90% in athymic nude mice xenografted with MDA-MB-468 cells. Together, the in vivo investigations demonstrated that treatment with 1 and 2 suppressed tumor growth without affecting normal tissues in mice. These phenylboronic acid nitrogen mustard prodrugs represent promising drug candidates for the treatment of TNBC. However, the mechanisms underlying their superior in vivo activity and selectivity as well as the correlation between H2O2 level and in vivo efficacy are not yet fully understood.
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Affiliation(s)
| | | | | | - Taufeeque Ali
- Department of Chemistry and
Biochemistry and the Milwaukee Institute for Drug Discovery, University of Wisconsin-Milwaukee, 3210 N. Cramer Street, Milwaukee, Wisconsin 53211, United States
| | - Anahit Campbell
- Department of Chemistry and
Biochemistry and the Milwaukee Institute for Drug Discovery, University of Wisconsin-Milwaukee, 3210 N. Cramer Street, Milwaukee, Wisconsin 53211, United States
| | - Qi Zhang
- Department of Chemistry and
Biochemistry and the Milwaukee Institute for Drug Discovery, University of Wisconsin-Milwaukee, 3210 N. Cramer Street, Milwaukee, Wisconsin 53211, United States
| | - Nurul Islam Setu
- Department of Chemistry and
Biochemistry and the Milwaukee Institute for Drug Discovery, University of Wisconsin-Milwaukee, 3210 N. Cramer Street, Milwaukee, Wisconsin 53211, United States
| | - Eron Saxon
- Department of Chemistry and
Biochemistry and the Milwaukee Institute for Drug Discovery, University of Wisconsin-Milwaukee, 3210 N. Cramer Street, Milwaukee, Wisconsin 53211, United States
| | - Nicolas M. Zahn
- Department of Chemistry and
Biochemistry and the Milwaukee Institute for Drug Discovery, University of Wisconsin-Milwaukee, 3210 N. Cramer Street, Milwaukee, Wisconsin 53211, United States
| | - Anna M. Benko
- Department of Chemistry and
Biochemistry and the Milwaukee Institute for Drug Discovery, University of Wisconsin-Milwaukee, 3210 N. Cramer Street, Milwaukee, Wisconsin 53211, United States
| | - Leggy A. Arnold
- Department of Chemistry and
Biochemistry and the Milwaukee Institute for Drug Discovery, University of Wisconsin-Milwaukee, 3210 N. Cramer Street, Milwaukee, Wisconsin 53211, United States
| | - Xiaohua Peng
- Department of Chemistry and
Biochemistry and the Milwaukee Institute for Drug Discovery, University of Wisconsin-Milwaukee, 3210 N. Cramer Street, Milwaukee, Wisconsin 53211, United States
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Lin HD, Yao CL, Ou WJ, Luo YH, Chen SC. 4-Aminobiphenyl suppresses homologous recombination repair by a reactive oxygen species-dependent p53/miR-513a-5p/p53 loop. Toxicology 2020; 444:152580. [DOI: 10.1016/j.tox.2020.152580] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2020] [Revised: 08/22/2020] [Accepted: 09/01/2020] [Indexed: 01/19/2023]
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Murphy MR, Kleiman FE. Connections between 3' end processing and DNA damage response: Ten years later. WILEY INTERDISCIPLINARY REVIEWS. RNA 2020; 11:e1571. [PMID: 31657151 PMCID: PMC7295566 DOI: 10.1002/wrna.1571] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/23/2019] [Revised: 09/10/2019] [Accepted: 09/17/2019] [Indexed: 12/23/2022]
Abstract
Ten years ago we reviewed how the cellular DNA damage response (DDR) is controlled by changes in the functional and structural properties of nuclear proteins, resulting in a timely coordinated control of gene expression that allows DNA repair. Expression of genes that play a role in DDR is regulated not only at transcriptional level during mRNA biosynthesis but also by changing steady-state levels due to turnover of the transcripts. The 3' end processing machinery, which is important in the regulation of mRNA stability, is involved in these gene-specific responses to DNA damage. Here, we review the latest mechanistic connections described between 3' end processing and DDR, with a special emphasis on alternative polyadenylation, microRNA and RNA binding proteins-mediated deadenylation, and discuss the implications of deregulation of these steps in DDR and human disease. This article is categorized under: RNA Processing > 3' End Processing RNA-Based Catalysis > Miscellaneous RNA-Catalyzed Reactions RNA in Disease and Development > RNA in Disease.
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Affiliation(s)
- Michael Robert Murphy
- Department of Chemistry, Hunter College and Biochemistry Program, The Graduate Center, City University of New York, New York, New York
| | - Frida Esther Kleiman
- Department of Chemistry, Hunter College and Biochemistry Program, The Graduate Center, City University of New York, New York, New York
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Plantamura I, Cosentino G, Cataldo A. MicroRNAs and DNA-Damaging Drugs in Breast Cancer: Strength in Numbers. Front Oncol 2018; 8:352. [PMID: 30234015 PMCID: PMC6129576 DOI: 10.3389/fonc.2018.00352] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2018] [Accepted: 08/10/2018] [Indexed: 11/25/2022] Open
Abstract
MicroRNAs are a class of small non-coding regulatory RNAs playing key roles in cancer. Breast cancer is the most common female malignancy worldwide and is categorized into four molecular subtypes: luminal A and B, HER2+ and triple-negative breast cancer (TNBC). Despite the development of multiple targeted therapies for luminal and HER2+ breast tumors, TNBC lacks specific therapeutic approaches, thus they are treated mainly with radio- and chemotherapy. The effectiveness of these therapeutic regimens is based on their ability to induce DNA damage, which is differentially resolved and repaired by normal vs. cancer cells. Recently, drugs directly targeting DNA repair mechanisms, such as PARP inhibitors, have emerged as attractive candidates for the future molecular targeted-therapy in breast cancer. These compounds prevent cancer cells to appropriate repair DNA double strand breaks and induce a phenomenon called synthetic lethality, that results from the concurrent inhibition of PARP and the absence of functional BRCA genes which prompt cell death. MicroRNAs are relevant players in most of the biological processes including DNA damage repair mechanisms. Consistently, the downregulation of DNA repair genes by miRNAs have been probe to improve the therapeutic effect of genotoxic drugs. In this review, we discuss how microRNAs can sensitize cancer cells to DNA-damaging drugs, through the regulation of DNA repair genes, and examine the most recent findings on their possible use as a therapeutic tools of treatment response in breast cancer.
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Affiliation(s)
- Ilaria Plantamura
- Molecular Targeting Unit, Research Department, Fondazione IRCCS Istituto Nazionale dei Tumori, Milan, Italy
| | - Giulia Cosentino
- Molecular Targeting Unit, Research Department, Fondazione IRCCS Istituto Nazionale dei Tumori, Milan, Italy
| | - Alessandra Cataldo
- Molecular Targeting Unit, Research Department, Fondazione IRCCS Istituto Nazionale dei Tumori, Milan, Italy
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8
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He M, Lin Y, Tang Y, Liu Y, Zhou W, Li C, Sun G, Guo M. miR-638 suppresses DNA damage repair by targeting SMC1A expression in terminally differentiated cells. Aging (Albany NY) 2017; 8:1442-56. [PMID: 27405111 PMCID: PMC4993341 DOI: 10.18632/aging.100998] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2016] [Accepted: 06/28/2016] [Indexed: 12/27/2022]
Abstract
The reduction of DNA damage repair capacity in terminally differentiated cells may be involved in sensitivity to cancer chemotherapy drugs; however, the underlying molecular mechanism is still not fully understood. Herein, we evaluated the role of miR-638 in the regulation of DNA damage repair in terminally differentiated cells. Our results show that miR-638 expression was up-regulated during cellular terminal differentiation and involved in mediating DNA damage repair processes. Results from a luciferase reporting experiment show that structural maintenance of chromosomes (SMC)1A was a potential target of miR-638; this was verified by western blot assays during cell differentiation and DNA damage induction. Overexpression of miR-638 enhanced the sensitivity of cancer cells to cisplatin, thus reducing cell viability in response to chemotherapy drug treatment. Furthermore, miR-638 overexpression affected DNA damage repair processes by interfering with the recruitment of the DNA damage repair-related protein, γH2AX, to DNA break sites. These findings indicate that miR-638 might act as a sensitizer in cancer chemotherapy and accompany chemotherapy drugs to enhance chemotherapeutic efficacy and to improve the chance of recovery from cancer.
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Affiliation(s)
- Mingyang He
- College of Life Sciences, Wuhan University, 430072 Wuhan, P. R. China
| | - Yi Lin
- College of Life Sciences, Wuhan University, 430072 Wuhan, P. R. China
| | - Yunlan Tang
- College of Life Sciences, Wuhan University, 430072 Wuhan, P. R. China
| | - Yi Liu
- College of Life Sciences, Wuhan University, 430072 Wuhan, P. R. China
| | - Weiwei Zhou
- College of Life Sciences, Wuhan University, 430072 Wuhan, P. R. China
| | - Chuang Li
- College of Life Sciences, Wuhan University, 430072 Wuhan, P. R. China
| | - Guihong Sun
- School of Basic Medical Sciences, Wuhan University, 430071 Wuhan, P.R. China
| | - Mingxiong Guo
- College of Life Sciences, Wuhan University, 430072 Wuhan, P. R. China
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9
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Feng NN, Fang Y, Zhang YN, Xu XW, Li Y, Wang JW, Li YL, Brandt-Rauf P, Xia ZL. Analysis of microRNA expression and micronuclei frequency in workers exposed to vinyl chloride monomer in China. Epigenomics 2017; 9:1093-1104. [PMID: 28749179 DOI: 10.2217/epi-2017-0028] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
AIM To identify differently expressed miRNAs associated with vinyl chloride monomer (VCM) and micronuclei (MN) frequency. METHOD In discovery stage, we used microarray to detect miRNAs expression in peripheral blood lymphocytes between six low and six high VCM-exposed workers grouped by medium cumulative exposure dose. Then we validated four miRNAs using real-time quantitative reverse transcription PCR (qRT-PCR) and detected the micronuclei frequencies using cytokinesis-block micronucleus assay in 94 VCM-exposed workers and 53 healthy control subjects. RESULTS & CONCLUSION We found eight miRNAs significantly downregulated and seven miRNAs upregulated (|Fold Change| >2; p < 0.05) in the high-exposure group through microarray. We validate that miR-222-3p, miR-146a-5p and miR-151a-5p were downregulated, while miR-22-3p was upregulated in VCM-exposed group (all p < 0.01). Furthermore, we found that expression of miR-22-3p was upregulated in the high micronuclei (MN) frequency subjects. In conclusion, our study suggested that these four miRNAs could be biomarkers of VCM exposure, and moreover miR-22-3p was correlated with MN frequency.
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Affiliation(s)
- Nan-Nan Feng
- Department of Occupational Health & Toxicology, School of Public Health, Fudan University, & Key Laboratory of Public Health & Safety of Ministry of Education of China, Shanghai, 200032, China.,Hongqiao International Institute of Medicine, Shanghai Tongren Hospital & Faculty of Public Health, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
| | - Yan Fang
- Department of Occupational Health & Toxicology, School of Public Health, Fudan University, & Key Laboratory of Public Health & Safety of Ministry of Education of China, Shanghai, 200032, China
| | - Ya-Nan Zhang
- Department of Occupational Health & Toxicology, School of Public Health, Fudan University, & Key Laboratory of Public Health & Safety of Ministry of Education of China, Shanghai, 200032, China
| | - Xiao-Wen Xu
- Department of Occupational Health & Toxicology, School of Public Health, Fudan University, & Key Laboratory of Public Health & Safety of Ministry of Education of China, Shanghai, 200032, China
| | - Yong Li
- Department of Occupational Health & Toxicology, School of Public Health, Fudan University, & Key Laboratory of Public Health & Safety of Ministry of Education of China, Shanghai, 200032, China
| | - Jin-Wei Wang
- Department of Occupational Health & Toxicology, School of Public Health, Fudan University, & Key Laboratory of Public Health & Safety of Ministry of Education of China, Shanghai, 200032, China
| | - Yong-Liang Li
- Department of Environmental & Occupational Health Sciences, School of Public Health, University of Illinois at Chicago, Chicago, IL 60612, USA
| | - Paul Brandt-Rauf
- Department of Environmental & Occupational Health Sciences, School of Public Health, University of Illinois at Chicago, Chicago, IL 60612, USA
| | - Zhao-Lin Xia
- Department of Occupational Health & Toxicology, School of Public Health, Fudan University, & Key Laboratory of Public Health & Safety of Ministry of Education of China, Shanghai, 200032, China
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10
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Fang Y, Zhang L, Li Z, Li Y, Huang C, Lu X. MicroRNAs in DNA Damage Response, Carcinogenesis, and Chemoresistance. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2017; 333:1-49. [DOI: 10.1016/bs.ircmb.2017.03.001] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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11
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He M, Zhou W, Li C, Guo M. MicroRNAs, DNA Damage Response, and Cancer Treatment. Int J Mol Sci 2016; 17:ijms17122087. [PMID: 27973455 PMCID: PMC5187887 DOI: 10.3390/ijms17122087] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2016] [Revised: 11/23/2016] [Accepted: 12/07/2016] [Indexed: 02/07/2023] Open
Abstract
As a result of various stresses, lesions caused by DNA-damaging agents occur constantly in each cell of the human body. Generally, DNA damage is recognized and repaired by the DNA damage response (DDR) machinery, and the cells survive. When repair fails, the genomic integrity of the cell is disrupted—a hallmark of cancer. In addition, the DDR plays a dual role in cancer development and therapy. Cancer radiotherapy and chemotherapy are designed to eliminate cancer cells by inducing DNA damage, which in turn can promote tumorigenesis. Over the past two decades, an increasing number of microRNAs (miRNAs), small noncoding RNAs, have been identified as participating in the processes regulating tumorigenesis and responses to cancer treatment with radiation therapy or genotoxic chemotherapies, by modulating the DDR. The purpose of this review is to summarize the recent findings on how miRNAs regulate the DDR and discuss the therapeutic functions of miRNAs in cancer in the context of DDR regulation.
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Affiliation(s)
- Mingyang He
- Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Wuhan University, Wuhan 430072, China.
| | - Weiwei Zhou
- Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Wuhan University, Wuhan 430072, China.
| | - Chuang Li
- Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Wuhan University, Wuhan 430072, China.
| | - Mingxiong Guo
- Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Wuhan University, Wuhan 430072, China.
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Jonak K, Kurpas M, Szoltysek K, Janus P, Abramowicz A, Puszynski K. A novel mathematical model of ATM/p53/NF- κB pathways points to the importance of the DDR switch-off mechanisms. BMC SYSTEMS BIOLOGY 2016; 10:75. [PMID: 27526774 PMCID: PMC4986247 DOI: 10.1186/s12918-016-0293-0] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/17/2016] [Accepted: 06/27/2016] [Indexed: 12/20/2022]
Abstract
Background Ataxia telangiectasia mutated (ATM) is a detector of double-strand breaks (DSBs) and a crucial component of the DNA damage response (DDR) along with p53 and NF- κB transcription factors and Wip1 phosphatase. Despite the recent advances in studying the DDR, the mechanisms of cell fate determination after DNA damage induction is still poorly understood. Results To investigate the importance of various DDR elements with particular emphasis on Wip1, we developed a novel mathematical model of ATM/p53/NF- κB pathways. Our results from in silico and in vitro experiments performed on U2-OS cells with Wip1 silenced to 25 % (Wip1-RNAi) revealed a strong dependence of cellular response to DNA damages on this phosphatase. Notably, Wip1-RNAi cells exhibited lower resistance to ionizing radiation (IR) resulting in smaller clonogenicity and higher apoptotic fraction. Conclusions In this article, we demonstrated that Wip1 plays a role as a gatekeeper of apoptosis and influences the pro-survival behaviour of cells – the level of Wip1 increases to block the apoptotic decision when DNA repair is successful. Moreover, we were able to verify the dynamics of proteins and transcripts, apoptotic fractions and cells viability obtained from stochastic simulations using in vitro approaches. Taken together, we demonstrated that the model can be successfully used in prediction of cellular behaviour after exposure to IR. Thus, our studies may provide further insights into key elements involved in the underlying mechanisms of the DDR. Electronic supplementary material The online version of this article (doi:10.1186/s12918-016-0293-0) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Katarzyna Jonak
- Faculty of Automatic Control, Electronics and Computer Science, Silesian University of Technology, Akademicka, Gliwice, 16, 44-100, Poland
| | - Monika Kurpas
- Faculty of Automatic Control, Electronics and Computer Science, Silesian University of Technology, Akademicka, Gliwice, 16, 44-100, Poland
| | - Katarzyna Szoltysek
- Maria Sklodowska-Curie Memorial Cancer Center and Institute of Oncology, Wybrzeze Armii Krajowej, Gliwice, 15, 44-400, Poland
| | - Patryk Janus
- Maria Sklodowska-Curie Memorial Cancer Center and Institute of Oncology, Wybrzeze Armii Krajowej, Gliwice, 15, 44-400, Poland
| | - Agata Abramowicz
- Maria Sklodowska-Curie Memorial Cancer Center and Institute of Oncology, Wybrzeze Armii Krajowej, Gliwice, 15, 44-400, Poland
| | - Krzysztof Puszynski
- Faculty of Automatic Control, Electronics and Computer Science, Silesian University of Technology, Akademicka, Gliwice, 16, 44-100, Poland.
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Wang Q, Goldstein M. Small RNAs Recruit Chromatin-Modifying Enzymes MMSET and Tip60 to Reconfigure Damaged DNA upon Double-Strand Break and Facilitate Repair. Cancer Res 2016; 76:1904-15. [DOI: 10.1158/0008-5472.can-15-2334] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2015] [Accepted: 01/03/2016] [Indexed: 11/16/2022]
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15
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Zhao K, Chen Y, Yang R, Bai Y, Li C, Li H, Xiong C. miR-424/322 is downregulated in the semen of patients with severe DNA damage and may regulate sperm DNA damage. Reprod Fertil Dev 2015; 28:RD15052. [PMID: 25872494 DOI: 10.1071/rd15052] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2014] [Accepted: 03/06/2015] [Indexed: 01/09/2023] Open
Abstract
Sperm DNA integrity is an essential factor for accurate transmission of genetic information. Human sperm DNA damage is a common cause of male infertility but the exact mechanism remains poorly understood. Considering the vital role of microRNA (miRNA) in multiple pathophysiological processes, we hypothesised that testicular miRNA is involved in sperm DNA damage during spermatogenesis. Infertile patients with high sperm DNA fragment index (DFI; n=94) were selected from 1090 infertile men and a total of 18 testis-specific seminal miRNAs previously identified from human seminal plasma were chosen and tested. miR-29c and miR-424 were downregulated in men with high DFI. The inhibition of these two miRNAs in mice confirmed the role of miR-424 (murine homologue miR-322) in sperm DNA damage during spermatogenesis; by contrast, miR-29c exhibited a negative result. Thus, miR-424/322 is involved in sperm DNA damage. Furthermore, the dysregulation of this miRNA can induce DNA double-strand breaks during spermatogenesis.
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Bottai G, Pasculli B, Calin GA, Santarpia L. Targeting the microRNA-regulating DNA damage/repair pathways in cancer. Expert Opin Biol Ther 2014; 14:1667-83. [PMID: 25190496 DOI: 10.1517/14712598.2014.950650] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
INTRODUCTION Maintenance of genome stability requires the integrity of the DNA repair machinery. DNA damage response (DDR) determines cell fate and regulates the expression of microRNAs (miRNAs), which in turn may also regulate important components of the DNA repair machinery. AREAS COVERED In this review, we describe the bidirectional connection between miRNAs and DDR and their link with important biological functions such as, DNA repair, cell cycle and apoptosis in cancer. Furthermore, we highlight the potential implications of recent findings on miRNA/DDR in determining chemotherapy response in cancer patients, and the use of these biomarkers for novel potential therapeutic approaches. EXPERT OPINION Defects in the DDR and deregulation of miRNAs are important hallmarks of human cancer. A full understanding of the mechanisms underlying the connection between miRNAs and DDR/DNA repair pathways will positively impact our knowledge on human tumor biology and on different responses to distinct drugs. Specific miRNAs interact with distinct DDR components and are promising targets for enhancing the effects of, and/or to overcome the resistance to, conventional chemotherapeutic agents. Finally, the development of innovative tools to deliver miRNA-targeting oligonucleotides may represents novel types of cancer interventions in clinic.
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Affiliation(s)
- Giulia Bottai
- IRCCS Clinical and Research Institute Humanitas, Experimental Therapeutics Unit , Via Manzoni 113 - 20089 Rozzano, Milan , Italy +39 02 8224 5173 ; +39 02 8224 5191 ; ;
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Abstract
SIGNIFICANCE The well-studied sequences in the human genome are those of protein-coding genes, which account for only 1%-2% of the total genome. However, with the advent of high-throughput transcriptome sequencing technology, we now know that about 90% of our genome is extensively transcribed and that the vast majority of them are transcribed into noncoding RNAs (ncRNAs). It is of great interest and importance to decipher the functions of these ncRNAs in humans. RECENT ADVANCES In the last decade, it has become apparent that ncRNAs play a crucial role in regulating gene expression in normal development, in stress responses to internal and environmental stimuli, and in human diseases. CRITICAL ISSUES In addition to those constitutively expressed structural RNA, such as ribosomal and transfer RNAs, regulatory ncRNAs can be classified as microRNAs (miRNAs), Piwi-interacting RNAs (piRNAs), small interfering RNAs (siRNAs), small nucleolar RNAs (snoRNAs), and long noncoding RNAs (lncRNAs). However, little is known about the biological features and functional roles of these ncRNAs in DNA repair and genome instability, although a number of miRNAs and lncRNAs are regulated in the DNA damage response. FUTURE DIRECTIONS A major goal of modern biology is to identify and characterize the full profile of ncRNAs with regard to normal physiological functions and roles in human disorders. Clinically relevant ncRNAs will also be evaluated and targeted in therapeutic applications.
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Affiliation(s)
- Guohui Wan
- 1 Department of Cancer Biology, The University of Texas MD Anderson Cancer Center , Houston, Texas
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Wang N, Zhu M, Tsao SW, Man K, Zhang Z, Feng Y. MiR-23a-mediated inhibition of topoisomerase 1 expression potentiates cell response to etoposide in human hepatocellular carcinoma. Mol Cancer 2013; 12:119. [PMID: 24103454 PMCID: PMC3856574 DOI: 10.1186/1476-4598-12-119] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2012] [Accepted: 10/02/2013] [Indexed: 12/19/2022] Open
Abstract
Background microRNAs have been shown to regulate the chemosensitivity of cancer cells. The aim of this study is to investigate the role and mechanism of mir-23a in enhancing the anti-tumor effect of topoisomerase 2A (TOP2A) poison etoposide in human hepatocellular carcinoma (HCC). Methods The anti-tumor effect of chemotherapeutic agents in HCC cells were examined in vitro and in vivo xenograft model. Expression of mRNA and miRNAs were determined by quantitative real-time PCR. Protein expression was analyzed by immunoblotting. Results Overexpression of mir-23a could significantly potentiate the in vitro and in vivo anti-tumor effect of etoposide; however, ectopic expression of miR-23a fails to sensitize HCC cells to 5-fluorouracil treatment, indicating the miR-23a-induced cancer cell hypersensitivity in chemotherapy is TOP2A-specific though miR-23a overexpression could not directly up-regulate TOP2A expression. Topoisomerase 1(TOP1) is down-regulated in miR-23a-overexpressed HCC cells. MiR-23a could directly bind to 3′untranslated region of TOP1 mRNA, and suppress the corresponding protein expression and inhibition of miR-23a further arguments the expression of TOP1. MiR-23a was up-regulated during DNA damage in cancer cells in line with the p53 expression. Up-regulation of p53 induces mir-23a expression, while suppression of p53 inhibits miR-23a in HCC cells. Conclusion Our study sheds light on the role of miR-23a as a potential target in regulating chemosensitivity of HCC cells.
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Affiliation(s)
- Ning Wang
- School of Chinese Medicine, Li Ka Shing Faculty of Medicine, The University of Hong Kong, 10 Sassoon Road, Pokfulam, Hong Kong, PR China.
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Stankevicins L, Almeida da Silva AP, Ventura Dos Passos F, Dos Santos Ferreira E, Menks Ribeiro MC, G David M, J Pires E, Ferreira-Machado SC, Vassetzky Y, de Almeida CE, de Moura Gallo CV. MiR-34a is up-regulated in response to low dose, low energy X-ray induced DNA damage in breast cells. Radiat Oncol 2013; 8:231. [PMID: 24094113 PMCID: PMC3829672 DOI: 10.1186/1748-717x-8-231] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2013] [Accepted: 10/01/2013] [Indexed: 12/31/2022] Open
Abstract
Background MicroRNAs are non-coding RNAs involved in the regulation of gene expression including DNA damage responses. Low doses of low energy X-ray radiation, similar to those used in mammographic exams, has been described to be genotoxic. In the present work we investigated the expression of miR-34a; a well described p53-regulated miRNA implicated in cell responses to X-ray irradiation at low doses. Methods Non-cancerous breast cell line MCF-10A and cancerous T-47D and MCF-7 cell lines were submitted to a low-energy X-ray irradiation (ranging from 28–30 Kv) using a dose of 5 Gy. The expression level of miR-34a, let-7a and miR-21 was assessed by qRT-PCR at 4 and 24 hours post-irradiation. DNA damage was then measured by comet assay and micronuclei estimation in MCF-10A and MCF-7 cell lines, where an increase of miR-34a levels could be observed after irradiation. The rate of apoptotic cells was estimated by nuclear staining and fluorescence microscopy. These experiments were also performed at low doses (3; 12 and 48 mGy) in MCF-10A and MCF-7 cell lines. Results We have observed an increase in miR-34a expression 4 hours post-irradiation at 5 Gy in MCF-10A and MCF-7 cell lines while its level did not change in T-47D, a breast cancer cell line bearing non-functional p53. At low doses, miR-34a was up-regulated in non-tumoral MCF-10A to a higher extent as compared to MCF-7. MiR-34a levels decreased 24 hours post-irradiation. We have also observed DNA damage and apoptosis at low-energy X-ray irradiation at low doses and the high dose in MCF-10A and MCF-7 4 and 24 hours post-irradiation relative to the mock control. Conclusion Low energy X-ray is able to promote DNA strand breaks and miR-34a might be involved in cell responses to low energy X-ray DNA damage. MiR-34a expression correlates with X-ray dose, time after irradiation and cell type. The present study reinforces the need of investigating consequences of low dose X-ray irradiation of breast cells.
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Affiliation(s)
- Luiza Stankevicins
- Departamento de Genética, Universidade do Estado do Rio de Janeiro, Instituto de Biologia Roberto Alcantara Gomes, 20550-013 Rio de Janeiro, Brazil.
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DNA modifications in atherosclerosis: From the past to the future. Atherosclerosis 2013; 230:202-9. [DOI: 10.1016/j.atherosclerosis.2013.07.038] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/14/2013] [Revised: 07/08/2013] [Accepted: 07/15/2013] [Indexed: 11/19/2022]
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Ohsawa R, Seol JH, Tyler JK. At the intersection of non-coding transcription, DNA repair, chromatin structure, and cellular senescence. Front Genet 2013; 4:136. [PMID: 23967007 PMCID: PMC3744812 DOI: 10.3389/fgene.2013.00136] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2013] [Accepted: 06/26/2013] [Indexed: 01/23/2023] Open
Abstract
It is well accepted that non-coding RNAs play a critical role in regulating gene expression. Recent paradigm-setting studies are now revealing that non-coding RNAs, other than microRNAs, also play intriguing roles in the maintenance of chromatin structure, in the DNA damage response, and in adult human stem cell aging. In this review, we will discuss the complex inter-dependent relationships among non-coding RNA transcription, maintenance of genomic stability, chromatin structure, and adult stem cell senescence. DNA damage-induced non-coding RNAs transcribed in the vicinity of the DNA break regulate recruitment of the DNA damage machinery and DNA repair efficiency. We will discuss the correlation between non-coding RNAs and DNA damage repair efficiency and the potential role of changing chromatin structures around double-strand break sites. On the other hand, induction of non-coding RNA transcription from the repetitive Alu elements occurs during human stem cell aging and hinders efficient DNA repair causing entry into senescence. We will discuss how this fine balance between transcription and genomic instability may be regulated by the dramatic changes to chromatin structure that accompany cellular senescence.
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Affiliation(s)
- Ryosuke Ohsawa
- Department of Biochemistry and Molecular Biology, University of Texas MD Anderson Cancer Center Houston, TX, USA
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Wan G, Zhang X, Langley RR, Liu Y, Hu X, Han C, Peng G, Ellis LM, Jones SN, Lu X. DNA-damage-induced nuclear export of precursor microRNAs is regulated by the ATM-AKT pathway. Cell Rep 2013; 3:2100-12. [PMID: 23791529 DOI: 10.1016/j.celrep.2013.05.038] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2012] [Revised: 04/25/2013] [Accepted: 05/23/2013] [Indexed: 12/13/2022] Open
Abstract
Expression of microRNAs (miRNAs) involves transcription of miRNA genes and maturation of the primary transcripts. Recent studies have shown that posttranscriptional processing of primary and precursor miRNAs is induced after DNA damage through regulatory RNA-binding proteins in the Drosha and Dicer complexes, such as DDX5 and KSRP. However, little is known about the regulation of nuclear export of pre-miRNAs in the DNA-damage response, a critical step in miRNA maturation. Here, we show that nuclear export of pre-miRNAs is accelerated after DNA damage in an ATM-dependent manner. The ATM-activated AKT kinase phosphorylates Nup153, a key component of the nucleopore, leading to enhanced interaction between Nup153 and Exportin-5 (XPO5) and increased nuclear export of pre-miRNAs. These findings define an important role of DNA-damage signaling in miRNA transport and maturation.
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Affiliation(s)
- Guohui Wan
- Department of Cancer Biology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
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Sharma V, Misteli T. Non-coding RNAs in DNA damage and repair. FEBS Lett 2013; 587:1832-9. [PMID: 23684639 DOI: 10.1016/j.febslet.2013.05.006] [Citation(s) in RCA: 69] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2013] [Revised: 05/03/2013] [Accepted: 05/06/2013] [Indexed: 02/07/2023]
Abstract
Non-coding RNAs (ncRNAs) are increasingly recognized as central players in diverse biological processes. Upon DNA damage, the DNA damage response (DDR) elicits a complex signaling cascade, which includes the induction of multiple ncRNA species. Recent studies indicate that DNA-damage induced ncRNAs contribute to regulation of cell cycle, apoptosis and DNA repair, and thus play a key role in maintaining genome stability. This review summarizes the emerging role of ncRNAs in DNA damage and repair.
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Affiliation(s)
- Vivek Sharma
- National Cancer Institute, National Institutes of Health, Bethesda, MD, USA
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Wan G, Mathur R, Hu X, Liu Y, Zhang X, Peng G, Lu X. Long non-coding RNA ANRIL (CDKN2B-AS) is induced by the ATM-E2F1 signaling pathway. Cell Signal 2013; 25:1086-95. [PMID: 23416462 DOI: 10.1016/j.cellsig.2013.02.006] [Citation(s) in RCA: 164] [Impact Index Per Article: 14.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2013] [Accepted: 02/08/2013] [Indexed: 12/27/2022]
Abstract
The maintenance of genome integrity is essential for the proper function and survival of all organisms. Human cells have evolved prompt and efficient DNA damage response to eliminate the detrimental effects of DNA lesions. The DNA damage response involves a complex network of processes that detect and repair DNA damage, in which long non-coding RNAs (lncRNAs), a new class of regulatory RNAs, may play important roles. Recent studies have identified a large number of lncRNAs in mammalian transcriptomes. However, little is known about the regulation and function of lncRNAs in the DNA damage response. In the present study, we demonstrate that one specific lncRNA, ANRIL, is transcriptionally up-regulated by the transcription factor E2F1 in an ATM-dependent manner following DNA damage, and elevated levels of ANRIL suppress the expression of INK4a, INK4b and ARF at the late-stage of DNA damage response, allowing the cell to return to normal at the completion of the DNA repair.
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Affiliation(s)
- Guohui Wan
- Department of Cancer Biology, The University of Texas M.D. Anderson Cancer Center, Houston, TX 77030, USA
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Spencer P, Fry RC, Kisby GE. Unraveling 50-Year-Old Clues Linking Neurodegeneration and Cancer to Cycad Toxins: Are microRNAs Common Mediators? Front Genet 2012; 3:192. [PMID: 23060898 PMCID: PMC3460211 DOI: 10.3389/fgene.2012.00192] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2012] [Accepted: 09/09/2012] [Indexed: 01/19/2023] Open
Abstract
Recognition of overlapping molecular signaling activated by a chemical trigger of cancer and neurodegeneration is new, but the path to this discovery has been long and potholed. Six conferences (1962–1972) examined the puzzling neurotoxic and carcinogenic properties of a then-novel toxin [cycasin: methylazoxymethanol (MAM)-β-d-glucoside] in cycad plants used traditionally for food and medicine on Guam where a complex neurodegenerative disease plagued the indigenous population. Affected families showed combinations of amyotrophic lateral sclerosis (ALS), parkinsonism (P), and/or a dementia (D) akin to Alzheimer’s disease (AD). Modernization saw declining disease rates on Guam and remarkable changes in clinical phenotype (ALS was replaced by P-D and then by D) and in two genetically distinct ALS-PDC-affected populations (Kii-Japan, West Papua-Indonesia) that used cycad seed medicinally. MAM forms DNA lesions – repaired by O6-methylguanine methyltransferase (MGMT) – that perturb mouse brain development and induce malignant tumors in peripheral organs. The brains of young adult MGMT-deficient mice given a single dose of MAM show DNA lesion-linked changes in cell-signaling pathways associated with miRNA-1, which is implicated in colon, liver, and prostate cancers, and in neurological disease, notably AD. MAM is metabolized to formaldehyde, a human carcinogen. Formaldehyde-responsive miRNAs predicted to modulate MAM-associated genes in the brains of MGMT-deficient mice include miR-17-5p and miR-18d, which regulate genes involved in tumor suppression, DNA repair, amyloid deposition, and neurotransmission. These findings marry cycad-associated ALS-PDC with colon, liver, and prostate cancer; they also add to evidence linking changes in microRNA status both to ALS, AD, and parkinsonism, and to cancer initiation and progression.
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Affiliation(s)
- Peter Spencer
- Global Health Center, Oregon Health and Science University Portland, OR, USA
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