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Villy MC, Le Ven A, Le Mentec M, Masliah-Planchon J, Houy A, Bièche I, Vacher S, Vincent-Salomon A, Dubois d'Enghien C, Schwartz M, Piperno-Neumann S, Matet A, Malaise D, Bubien V, Lortholary A, Ait Omar A, Cavaillé M, Stoppa-Lyonnet D, Cassoux N, Stern MH, Rodrigues M, Golmard L, Colas C. Familial uveal melanoma and other tumors in 25 families with monoallelic germline MBD4 variants. J Natl Cancer Inst 2024; 116:580-587. [PMID: 38060262 DOI: 10.1093/jnci/djad248] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2023] [Revised: 11/02/2023] [Accepted: 11/18/2023] [Indexed: 12/08/2023] Open
Abstract
BACKGROUND Monoallelic germline MBD4 pathogenic variants were recently reported to cause a predisposition to uveal melanoma, associated with a specific tumor mutational signature and good response to immunotherapy. Monoallelic tumor pathogenic variants have also been described in brain tumors, breast cancers, and myxofibrosarcomas, whereas biallelic germline MBD4 pathogenic variants have been involved in a recessive hereditary adenomatous polyposis and a specific type of acute myeloid leukemia. METHODS We analyzed MBD4 for all patients with a diagnosis of uveal melanoma at Institut Curie since July 2021 and in the 3240 consecutive female probands explored at the Institut Curie for suspicion of predisposition to breast cancer between July 2021 and February 2023. RESULTS We describe 25 families whose probands carry a monoallelic germline pathogenic variant in MBD4. Eighteen of these families presented with uveal melanoma (including a case patient with multiple uveal melanoma), and 7 families presented with breast cancer. Family histories showed the first familial case of uveal melanoma in monoallelic MBD4 pathogenic variant carriers and other various types of cancers in relatives, especially breast, renal, and colorectal tumors. CONCLUSIONS Monoallelic MBD4 pathogenic variant may explain some cases of familial and multiple uveal melanoma as well as various cancer types, expanding the tumor spectrum of this predisposition. Further genetic testing in relatives combined with molecular tumor analyses will help define the tumor spectrum and estimate each tumor's risk.
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Affiliation(s)
- Marie-Charlotte Villy
- Department of Genetics, Institut Curie, Paris, France
- Université Paris Cité, Paris, France
| | - Anaïs Le Ven
- Department of Genetics, Institut Curie, Paris, France
- Paris Sciences & Lettres Research University, Paris, France
- Inserm U830, DNA Repair and Uveal Melanoma (D.R.U.M.), Paris, France
| | - Marine Le Mentec
- Department of Genetics, Institut Curie, Paris, France
- Paris Sciences & Lettres Research University, Paris, France
| | - Julien Masliah-Planchon
- Department of Genetics, Institut Curie, Paris, France
- Paris Sciences & Lettres Research University, Paris, France
| | - Alexandre Houy
- Paris Sciences & Lettres Research University, Paris, France
- Inserm U830, DNA Repair and Uveal Melanoma (D.R.U.M.), Paris, France
| | - Ivan Bièche
- Department of Genetics, Institut Curie, Paris, France
- Université Paris Cité, Paris, France
| | - Sophie Vacher
- Department of Genetics, Institut Curie, Paris, France
- Paris Sciences & Lettres Research University, Paris, France
| | - Anne Vincent-Salomon
- Department of Genetics, Institut Curie, Paris, France
- Paris Sciences & Lettres Research University, Paris, France
| | - Catherine Dubois d'Enghien
- Department of Genetics, Institut Curie, Paris, France
- Paris Sciences & Lettres Research University, Paris, France
| | - Mathias Schwartz
- Department of Genetics, Institut Curie, Paris, France
- Paris Sciences & Lettres Research University, Paris, France
| | - Sophie Piperno-Neumann
- Paris Sciences & Lettres Research University, Paris, France
- Department of Medical Oncology, Institut Curie, Paris, France
| | - Alexandre Matet
- Université Paris Cité, Paris, France
- Department of Ocular Oncology, Institut Curie, Paris, France
| | - Denis Malaise
- Paris Sciences & Lettres Research University, Paris, France
- Department of Ocular Oncology, Institut Curie, Paris, France
| | | | - Alain Lortholary
- Department of Medical Oncology, GINECO-Hôpital Privé du Confluent, Nantes, France
| | - Amal Ait Omar
- Department of Gastroenterology, AP-HP, Hôpital Avicenne, Bobigny, France
| | - Mathias Cavaillé
- Department of Oncogenetics, Centre Jean Perrin, Université Clermont Auvergne, INSERM, U1240 Imagerie Moléculaire et Stratégies Théranostiques, AURAGEN, Clermont-Ferrand, France
| | - Dominique Stoppa-Lyonnet
- Department of Genetics, Institut Curie, Paris, France
- Université Paris Cité, Paris, France
- Inserm U830, DNA Repair and Uveal Melanoma (D.R.U.M.), Paris, France
| | - Nathalie Cassoux
- Université Paris Cité, Paris, France
- Department of Ocular Oncology, Institut Curie, Paris, France
| | - Marc-Henri Stern
- Department of Genetics, Institut Curie, Paris, France
- Paris Sciences & Lettres Research University, Paris, France
- Inserm U830, DNA Repair and Uveal Melanoma (D.R.U.M.), Paris, France
| | - Manuel Rodrigues
- Paris Sciences & Lettres Research University, Paris, France
- Inserm U830, DNA Repair and Uveal Melanoma (D.R.U.M.), Paris, France
- Department of Medical Oncology, Institut Curie, Paris, France
| | - Lisa Golmard
- Department of Genetics, Institut Curie, Paris, France
- Paris Sciences & Lettres Research University, Paris, France
| | - Chrystelle Colas
- Department of Genetics, Institut Curie, Paris, France
- Paris Sciences & Lettres Research University, Paris, France
- Inserm U830, DNA Repair and Uveal Melanoma (D.R.U.M.), Paris, France
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Wang G, Zhou Y, Yi B, Long Y, Ma B, Zhang Y. Comprehensive analysis of the prognostic value and biological function of TDG in hepatocellular carcinoma. Cell Cycle 2023; 22:1478-1495. [PMID: 37224078 PMCID: PMC10281473 DOI: 10.1080/15384101.2023.2216501] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Revised: 03/30/2023] [Accepted: 04/27/2023] [Indexed: 05/26/2023] Open
Abstract
Epigenetics plays an important role in the malignant progression of tumors, in which DNA methylation can alter genetic performance without altering the DNA sequence. As a key regulator demethylation, thymine-DNA glycosylase (TDG) has been reported to participate in malignant progression of multiple tumors. In this study, we demonstrate that TDG is highly expressed in hepatocellular carcinoma (HCC) and its high expression is closely related to the poor prognosis of patients. Decreasing TDG expression can significantly inhibit the malignant biological behavior of HCC cells. ABL proto-oncogene 1(ABL1) was identified as a downstream gene regulated by TDG demethylation. In addition, TDG can affect the Hippo signaling pathway through ABL1 to regulate HCC cell proliferation, apoptosis, invasion and migration. Overall, our study demonstrated that TDG reduces DNA methylation of ABL1, increases ABL1 protein expression, and affects the Hippo signaling pathway to regulate the malignant progression of HCC.
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Affiliation(s)
- Guoliang Wang
- Department of Hepatobiliary Surgery, Department of Organ Transplantation, Guizhou Provincial People’s Hospital, Guiyang, Guizhou, China
| | - Yinwen Zhou
- Department of Surgery, Zunyi Medical University, Zunyi, Guizhou, China
| | - Bin Yi
- Department of Hepatobiliary Surgery, Department of Organ Transplantation, Guizhou Provincial People’s Hospital, Guiyang, Guizhou, China
| | - Yanli Long
- Department of Pathology, Guizhou Provincial People’s Hospital, Guiyang, Guizhou, China
| | - Bo Ma
- Department of Hepatobiliary Surgery, Department of Organ Transplantation, Guizhou Provincial People’s Hospital, Guiyang, Guizhou, China
| | - Yi Zhang
- Department of Hepatobiliary Surgery, Department of Organ Transplantation, Guizhou Provincial People’s Hospital, Guiyang, Guizhou, China
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3
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Liu C, Jiang H, Li Y, Xue B, Yao YY, Yang ZZ. Development of a QM/MM(ABEEM) method combined with a polarizable force field to investigate the excision reaction mechanism of damaged thymine. Phys Chem Chem Phys 2023; 25:3432-3448. [PMID: 36637033 DOI: 10.1039/d2cp05873a] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
This paper focuses on the development of a quantum mechanics/molecular mechanics method using the ABEEM polarizable force field (QM/MM(ABEEM) method) to investigate the excision reaction mechanism of damaged thymine. This method does not simply combine the QM method with the polarizable force field. A valence electronegativity piecewise function with the distance between atoms as a variable is introduced to describe the atomic partial charges, and changes greatly during the reaction process. At the same time, the charge transfer effect is treated using the condition of local charge conservation. Compared with the traditional QM/MM method, the QM/MM(ABEEM) method can more accurately simulate the polarization effect and charge transfer effect in the reaction process. Focusing on the controversial problems of the excision of damaged bases, six reaction pathways were designed for monofunctional and difunctional deglycosylation of neutral bases and protonated bases. The results show that the QM/MM(ABEEM) method accurately simulates the polarization effect, charge transfer effect, activation energy and other properties of the reaction process. The process in which the active residue Asp activates the nucleophile H2O to attack the protonated base is the preferred path. The average activation energy and free activation energy of the protonated base are 7.00-14.00 kcal mol-1 lower than that of the neutral base. The study in this paper is helpful to understand the mechanism of repair enzymes in repairing bases.
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Affiliation(s)
- Cui Liu
- School of Chemistry and Chemical Engineering, Liaoning Normal University, Dalian, 116029, People's Republic of China.
| | - He Jiang
- School of Chemistry and Chemical Engineering, Liaoning Normal University, Dalian, 116029, People's Republic of China.
| | - Yue Li
- School of Chemistry and Chemical Engineering, Liaoning Normal University, Dalian, 116029, People's Republic of China.
| | - Bing Xue
- School of Chemistry and Chemical Engineering, Liaoning Normal University, Dalian, 116029, People's Republic of China.
| | - Yu-Ying Yao
- School of Chemistry and Chemical Engineering, Liaoning Normal University, Dalian, 116029, People's Republic of China.
| | - Zhong-Zhi Yang
- School of Chemistry and Chemical Engineering, Liaoning Normal University, Dalian, 116029, People's Republic of China.
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The Role of Thymine DNA Glycosylase in Transcription, Active DNA Demethylation, and Cancer. Cancers (Basel) 2022; 14:cancers14030765. [PMID: 35159032 PMCID: PMC8833622 DOI: 10.3390/cancers14030765] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2021] [Revised: 01/28/2022] [Accepted: 01/28/2022] [Indexed: 02/04/2023] Open
Abstract
Simple Summary Thymine DNA Glycosylase (TDG) is a DNA repair protein that plays an important role in gene regulation. Recent studies have shown that TDG interacts with various transcription factors to activate target genes. TDG also functions in a pathway known as active DNA demethylation, which removes 5-mC from DNA and replaces it with unmethylated cytosine. In this review, we summarize the various functions of TDG in gene regulation as well as the physiological relevance of TDG in cancer. Abstract DNA methylation is an essential covalent modification that is required for growth and development. Once considered to be a relatively stable epigenetic mark, many studies have established that DNA methylation is dynamic. The 5-methylcytosine (5-mC) mark can be removed through active DNA demethylation in which 5-mC is converted to an unmodified cytosine through an oxidative pathway coupled to base excision repair (BER). The BER enzyme Thymine DNA Glycosylase (TDG) plays a key role in active DNA demethylation by excising intermediates of 5-mC generated by this process. TDG acts as a key player in transcriptional regulation through its interactions with various nuclear receptors and transcription factors, in addition to its involvement in classical BER and active DNA demethylation, which serve to protect the stability of the genome and epigenome, respectively. Recent animal studies have identified a connection between the loss of Tdg and the onset of tumorigenesis. In this review, we summarize the recent findings on TDG’s function as a transcriptional regulator as well as the physiological relevance of TDG and active DNA demethylation in cancer.
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Hsu CW, Sowers ML, Baljinnyam T, Herring JL, Hackfeld LC, Tang H, Zhang K, Sowers LC. Measurement of deaminated cytosine adducts in DNA using a novel hybrid thymine DNA glycosylase. J Biol Chem 2022; 298:101638. [PMID: 35085553 PMCID: PMC8861164 DOI: 10.1016/j.jbc.2022.101638] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2021] [Revised: 01/13/2022] [Accepted: 01/17/2022] [Indexed: 01/16/2023] Open
Abstract
The hydrolytic deamination of cytosine and 5-methylcytosine drives many of the transition mutations observed in human cancer. The deamination-induced mutagenic intermediates include either uracil or thymine adducts mispaired with guanine. While a substantial array of methods exist to measure other types of DNA adducts, the cytosine deamination adducts pose unusual analytical problems, and adequate methods to measure them have not yet been developed. We describe here a novel hybrid thymine DNA glycosylase (TDG) that is comprised of a 29-amino acid sequence from human TDG linked to the catalytic domain of a thymine glycosylase found in an archaeal thermophilic bacterium. Using defined-sequence oligonucleotides, we show that hybrid TDG has robust mispair-selective activity against deaminated U:G and T:G mispairs. We have further developed a method for separating glycosylase-released free bases from oligonucleotides and DNA followed by GC-MS/MS quantification. Using this approach, we have measured for the first time the levels of total uracil, U:G, and T:G pairs in calf thymus DNA. The method presented here will allow the measurement of the formation, persistence, and repair of a biologically important class of deaminated cytosine adducts.
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Affiliation(s)
- Chia Wei Hsu
- Department of Pharmacology and Toxicology, University of Texas Medical Branch, Galveston, Texas, USA,MD-PhD Combined Degree Program, University of Texas Medical Branch, Galveston, Texas, USA
| | - Mark L. Sowers
- Department of Pharmacology and Toxicology, University of Texas Medical Branch, Galveston, Texas, USA,MD-PhD Combined Degree Program, University of Texas Medical Branch, Galveston, Texas, USA
| | - Tuvshintugs Baljinnyam
- Department of Pharmacology and Toxicology, University of Texas Medical Branch, Galveston, Texas, USA
| | - Jason L. Herring
- Department of Pharmacology and Toxicology, University of Texas Medical Branch, Galveston, Texas, USA
| | - Linda C. Hackfeld
- Department of Pharmacology and Toxicology, University of Texas Medical Branch, Galveston, Texas, USA
| | - Hui Tang
- Department of Pharmacology and Toxicology, University of Texas Medical Branch, Galveston, Texas, USA
| | - Kangling Zhang
- Department of Pharmacology and Toxicology, University of Texas Medical Branch, Galveston, Texas, USA
| | - Lawrence C. Sowers
- Department of Pharmacology and Toxicology, University of Texas Medical Branch, Galveston, Texas, USA,Department of Internal Medicine, University of Texas Medical Branch, Galveston, Texas, USA,For correspondence: Lawrence C. Sowers
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6
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Derrien AC, Rodrigues M, Eeckhoutte A, Dayot S, Houy A, Mobuchon L, Gardrat S, Lequin D, Ballet S, Pierron G, Alsafadi S, Mariani O, El-Marjou A, Matet A, Colas C, Cassoux N, Stern MH. Germline MBD4 Mutations and Predisposition to Uveal Melanoma. J Natl Cancer Inst 2021; 113:80-87. [PMID: 32239153 PMCID: PMC7781447 DOI: 10.1093/jnci/djaa047] [Citation(s) in RCA: 35] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2019] [Revised: 03/19/2020] [Accepted: 03/26/2020] [Indexed: 12/11/2022] Open
Abstract
Background Uveal melanoma (UM) arises from malignant transformation of melanocytes in the uveal tract of the eye. This rare tumor has a poor outcome with frequent chemo-resistant liver metastases. BAP1 is the only known predisposing gene for UM. UMs are generally characterized by low tumor mutation burden, but some UMs display a high level of CpG>TpG mutations associated with MBD4 inactivation. Here, we explored the incidence of germline MBD4 variants in a consecutive series of 1093 primary UM case patients and a series of 192 UM tumors with monosomy 3 (M3). Methods We performed MBD4 targeted sequencing on pooled germline (n = 1093) and tumor (n = 192) DNA samples of UM patients. MBD4 variants (n = 28) were validated by Sanger sequencing. We performed whole-exome sequencing on available tumor samples harboring MBD4 variants (n = 9). Variants of unknown pathogenicity were further functionally assessed. Results We identified 8 deleterious MBD4 mutations in the consecutive UM series, a 9.15-fold (95% confidence interval = 4.24-fold to 19.73-fold) increased incidence compared with the general population (Fisher exact test, P = 2.00 × 10–5, 2-sided), and 4 additional deleterious MBD4 mutations in the M3 cohort, including 3 germline and 1 somatic mutations. Tumors carrying deleterious MBD4 mutations were all associated with high tumor mutation burden and a CpG>TpG hypermutator phenotype. Conclusions We demonstrate that MBD4 is a new predisposing gene for UM associated with hypermutated M3 tumors. The tumor spectrum of this predisposing condition will likely expand with the addition of MBD4 to diagnostic panels. Tumors arising in such a context should be recognized because they may respond to immunotherapy.
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Affiliation(s)
- Anne-Céline Derrien
- Inserm U830, DNA Repair and Uveal Melanoma (D.R.U.M.), Equipe Labellisée Par la Ligue Nationale Contre le Cancer, Paris, France
| | - Manuel Rodrigues
- Inserm U830, DNA Repair and Uveal Melanoma (D.R.U.M.), Equipe Labellisée Par la Ligue Nationale Contre le Cancer, Paris, France.,Department of Medical Oncology, Institut Curie, PSL Research University, Paris, France
| | - Alexandre Eeckhoutte
- Inserm U830, DNA Repair and Uveal Melanoma (D.R.U.M.), Equipe Labellisée Par la Ligue Nationale Contre le Cancer, Paris, France
| | - Stéphane Dayot
- Inserm U830, DNA Repair and Uveal Melanoma (D.R.U.M.), Equipe Labellisée Par la Ligue Nationale Contre le Cancer, Paris, France
| | - Alexandre Houy
- Inserm U830, DNA Repair and Uveal Melanoma (D.R.U.M.), Equipe Labellisée Par la Ligue Nationale Contre le Cancer, Paris, France
| | - Lenha Mobuchon
- Inserm U830, DNA Repair and Uveal Melanoma (D.R.U.M.), Equipe Labellisée Par la Ligue Nationale Contre le Cancer, Paris, France
| | - Sophie Gardrat
- Inserm U830, DNA Repair and Uveal Melanoma (D.R.U.M.), Equipe Labellisée Par la Ligue Nationale Contre le Cancer, Paris, France.,Department of Biopathology, Institut Curie, PSL Research University, Paris, France
| | - Delphine Lequin
- Department of Biopathology, Institut Curie, PSL Research University, Paris, France
| | - Stelly Ballet
- Department of Biopathology, Institut Curie, PSL Research University, Paris, France
| | - Gaëlle Pierron
- Department of Biopathology, Institut Curie, PSL Research University, Paris, France
| | - Samar Alsafadi
- Inserm U830, DNA Repair and Uveal Melanoma (D.R.U.M.), Equipe Labellisée Par la Ligue Nationale Contre le Cancer, Paris, France.,Translational Research Department, Institut Curie, PSL Research University, Paris, France
| | - Odette Mariani
- Biological Resource Center, Institut Curie, PSL Research University, Paris, France
| | - Ahmed El-Marjou
- Institut Curie, PSL Research University, UMR144, Recombinant Protein Facility, Paris, France
| | - Alexandre Matet
- Department of Ocular Oncology, Institut Curie, Paris, France.,Faculty of Medicine, University of Paris Descartes, Paris, France
| | | | - Nathalie Cassoux
- Department of Ocular Oncology, Institut Curie, Paris, France.,Faculty of Medicine, University of Paris Descartes, Paris, France
| | - Marc-Henri Stern
- Inserm U830, DNA Repair and Uveal Melanoma (D.R.U.M.), Equipe Labellisée Par la Ligue Nationale Contre le Cancer, Paris, France.,Department of Genetics, Institut Curie, Paris, France
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Insights into the substrate discrimination mechanisms of methyl-CpG-binding domain 4. Biochem J 2021; 478:1985-1997. [PMID: 33960375 DOI: 10.1042/bcj20210017] [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: 01/15/2021] [Revised: 05/05/2021] [Accepted: 05/07/2021] [Indexed: 11/17/2022]
Abstract
G:T mismatches, the major mispairs generated during DNA metabolism, are repaired in part by mismatch-specific DNA glycosylases such as methyl-CpG-binding domain 4 (MBD4) and thymine DNA glycosylase (TDG). Mismatch-specific DNA glycosylases must discriminate the mismatches against million-fold excess correct base pairs. MBD4 efficiently removes thymine opposite guanine but not opposite adenine. Previous studies have revealed that the substrate thymine is flipped out and enters the catalytic site of the enzyme, while the estranged guanine is stabilized by Arg468 of MBD4. To gain further insights into the mismatch discrimination mechanism of MBD4, we assessed the glycosylase activity of MBD4 toward various base pairs. In addition, we determined a crystal structure of MBD4 bound to T:O6-methylguanine-containing DNA, which suggests the O6 and N2 of purine and the O4 of pyrimidine are required to be a substrate for MBD4. To understand the role of the Arg468 finger in catalysis, we evaluated the glycosylase activity of MBD4 mutants, which revealed the guanidinium moiety of Arg468 may play an important role in catalysis. D560N/R468K MBD4 bound to T:G mismatched DNA shows that the side chain amine moiety of the Lys stabilizes the flipped-out thymine by a water-mediated phosphate pinching, while the backbone carbonyl oxygen of the Lys engages in hydrogen bonds with N2 of the estranged guanine. Comparison of various DNA glycosylase structures implies the guanidinium and amine moieties of Arg and Lys, respectively, may involve in discriminating between substrate mismatches and nonsubstrate base pairs.
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Reading Targeted DNA Damage in the Active Demethylation Pathway: Role of Accessory Domains of Eukaryotic AP Endonucleases and Thymine-DNA Glycosylases. J Mol Biol 2020:S0022-2836(19)30720-X. [DOI: 10.1016/j.jmb.2019.12.020] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2019] [Revised: 11/24/2019] [Accepted: 12/05/2019] [Indexed: 01/07/2023]
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9
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Koliadenko V, Wilanowski T. Additional functions of selected proteins involved in DNA repair. Free Radic Biol Med 2020; 146:1-15. [PMID: 31639437 DOI: 10.1016/j.freeradbiomed.2019.10.010] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/12/2019] [Revised: 10/16/2019] [Accepted: 10/16/2019] [Indexed: 12/30/2022]
Abstract
Protein moonlighting is a phenomenon in which a single polypeptide chain can perform a number of different unrelated functions. Here we present our analysis of moonlighting in the case of selected DNA repair proteins which include G:T mismatch-specific thymine DNA glycosylase (TDG), methyl-CpG-binding domain protein 4 (MBD4), apurinic/apyrimidinic endonuclease 1 (APE1), AlkB homologs, poly (ADP-ribose) polymerase 1 (PARP-1) and single-strand selective monofunctional uracil DNA glycosylase 1 (SMUG1). Most of their additional functions are not accidental and clear patterns are emerging. Participation in RNA metabolism is not surprising as bases occurring in RNA are the same or very similar to those in DNA. Other common additional function involves regulation of transcription. This is not unexpected as these proteins bind to specific DNA regions for DNA repair, hence they can also be recruited to regulate transcription. Participation in demethylation and replication of DNA appears logical as well. Some of the multifunctional DNA repair proteins play major roles in many diseases, including cancer. However, their moonlighting might prove a major difficulty in the development of new therapies because it will not be trivial to target a single protein function without affecting its other functions that are not related to the disease.
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Affiliation(s)
- Vlada Koliadenko
- Institute of Genetics and Biotechnology, Faculty of Biology, University of Warsaw, Ilji Miecznikowa 1, 02-096, Warsaw, Poland
| | - Tomasz Wilanowski
- Institute of Genetics and Biotechnology, Faculty of Biology, University of Warsaw, Ilji Miecznikowa 1, 02-096, Warsaw, Poland.
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Petri net-based model of the human DNA base excision repair pathway. PLoS One 2019; 14:e0217913. [PMID: 31518347 PMCID: PMC6743755 DOI: 10.1371/journal.pone.0217913] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2018] [Accepted: 05/21/2019] [Indexed: 12/14/2022] Open
Abstract
Cellular DNA is daily exposed to several damaging agents causing a plethora of DNA lesions. As a first aid to restore DNA integrity, several enzymes got specialized in damage recognition and lesion removal during the process called base excision repair (BER). A large number of DNA damage types and several different readers of nucleic acids lesions during BER pathway as well as two sub-pathways were considered in the definition of a model using the Petri net framework. The intuitive graphical representation in combination with precise mathematical analysis methods are the strong advantages of the Petri net-based representation of biological processes and make Petri nets a promising approach for modeling and analysis of human BER. The reported results provide new information that will aid efforts to characterize in silico knockouts as well as help to predict the sensitivity of the cell with inactivated repair proteins to different types of DNA damage. The results can also help in identifying the by-passing pathways that may lead to lack of pronounced phenotypes associated with mutations in some of the proteins. This knowledge is very useful when DNA damage-inducing drugs are introduced for cancer therapy, and lack of DNA repair is desirable for tumor cell death.
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11
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Sarre A, Stelter M, Rollo F, De Bonis S, Seck A, Hognon C, Ravanat JL, Monari A, Dehez F, Moe E, Timmins J. The three Endonuclease III variants of Deinococcus radiodurans possess distinct and complementary DNA repair activities. DNA Repair (Amst) 2019; 78:45-59. [DOI: 10.1016/j.dnarep.2019.03.014] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2018] [Revised: 03/26/2019] [Accepted: 03/27/2019] [Indexed: 11/26/2022]
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12
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Shinmura K, Kato H, Kawanishi Y, Goto M, Tao H, Yoshimura K, Nakamura S, Misawa K, Sugimura H. Defective repair capacity of variant proteins of the DNA glycosylase NTHL1 for 5-hydroxyuracil, an oxidation product of cytosine. Free Radic Biol Med 2019; 131:264-273. [PMID: 30552997 DOI: 10.1016/j.freeradbiomed.2018.12.010] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/28/2018] [Revised: 12/09/2018] [Accepted: 12/11/2018] [Indexed: 12/20/2022]
Abstract
The NTHL1 gene encodes DNA glycosylase, which is involved in base excision repair, and biallelic mutations of this gene result in NTHL1-associated polyposis (NAP), a hereditary disease characterized by colorectal polyposis and multiple types of carcinomas. However, no proper functional characterization of variant NTHL1 proteins has been done so far. Herein, we report functional evaluation of variant NTHL1 proteins to aid in the accurate diagnosis of NAP. First, we investigated whether it would be appropriate to use 5-hydroxyuracil (5OHU), an oxidation product of cytosine, for the evaluation. In the supF forward mutation assay, 5OHU caused an increase of the mutation frequency in human cells, and the C→T mutation was predominant among the 5OHU-induced mutations. In addition, in DNA cleavage activity assay, 5OHU was excised by NTHL1 as well as four other DNA glycosylases (SMUG1, NEIL1, TDG, and UNG2). When human cells overexpressing the five DNA glycosylases were established, it was found that each of the five DNA glycosylases, including NTHL1, had the ability to suppress 5OHU-induced mutations. Based on the above results, we performed functional evaluation of eight NTHL1 variants using 5OHU-containing DNA substrate or shuttle plasmid. The DNA cleavage activity assay showed that the variants of NTHL1, Q90X, Y130X, R153X, and Q287X, but not R19Q, V179I, V217F, or G286S, showed defective repair activity for 5OHU and two other oxidatively damaged bases. Moreover, the supF forward mutation assay showed that the four truncated-type NTHL1 variants showed a reduced ability to suppress 5OHU-induced mutations in human cells. These results suggest that the NTHL1 variants Q90X, Y130X, R153X, and Q287X, but not R19Q, V179I, V217F, or G286S, were defective in 5OHU repair and the alleles encoding them were considered to be pathogenic for NAP.
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Affiliation(s)
- Kazuya Shinmura
- Department of Tumor Pathology, Hamamatsu University School of Medicine, 1-20-1 Handayama, Higashi Ward, Hamamatsu, Japan.
| | - Hisami Kato
- Department of Tumor Pathology, Hamamatsu University School of Medicine, 1-20-1 Handayama, Higashi Ward, Hamamatsu, Japan
| | - Yuichi Kawanishi
- Advanced Research Facilities and Services, Preeminent Medical Photonics Education and Research Center, Hamamatsu University School of Medicine, Hamamatsu, Japan
| | - Masanori Goto
- Division of Tumor Pathology, Department of Pathology, Asahikawa Medical University, Asahikawa, Japan
| | - Hong Tao
- Department of Tumor Pathology, Hamamatsu University School of Medicine, 1-20-1 Handayama, Higashi Ward, Hamamatsu, Japan
| | - Katsuhiro Yoshimura
- Department of Tumor Pathology, Hamamatsu University School of Medicine, 1-20-1 Handayama, Higashi Ward, Hamamatsu, Japan
| | - Satoki Nakamura
- Department of Tumor Pathology, Hamamatsu University School of Medicine, 1-20-1 Handayama, Higashi Ward, Hamamatsu, Japan
| | - Kiyoshi Misawa
- Department of Otolaryngology/Head and Neck Surgery, Hamamatsu University School of Medicine, Hamamatsu, Japan
| | - Haruhiko Sugimura
- Department of Tumor Pathology, Hamamatsu University School of Medicine, 1-20-1 Handayama, Higashi Ward, Hamamatsu, Japan
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13
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Li J, Svilar D, McClellan S, Kim JH, Ahn EYE, Vens C, Wilson DM, Sobol RW. DNA Repair Molecular Beacon assay: a platform for real-time functional analysis of cellular DNA repair capacity. Oncotarget 2018; 9:31719-31743. [PMID: 30167090 PMCID: PMC6114979 DOI: 10.18632/oncotarget.25859] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2018] [Accepted: 07/12/2018] [Indexed: 12/15/2022] Open
Abstract
Numerous studies have shown that select DNA repair enzyme activities impact response and/or toxicity of genotoxins, suggesting a requirement for enzyme functional analyses to bolster precision medicine or prevention. To address this need, we developed a DNA Repair Molecular Beacon (DRMB) platform that rapidly measures DNA repair enzyme activity in real-time. The DRMB assay is applicable for discovery of DNA repair enzyme inhibitors, for the quantification of enzyme rates and is sufficiently sensitive to differentiate cellular enzymatic activity that stems from variation in expression or effects of amino acid substitutions. We show activity measures of several different base excision repair (BER) enzymes, including proteins with tumor-identified point mutations, revealing lesion-, lesion-context- and cell-type-specific repair dependence; suggesting application for DNA repair capacity analysis of tumors. DRMB measurements using lysates from isogenic control and APE1-deficient human cells suggests the major mechanism of base lesion removal by most DNA glycosylases may be mono-functional base hydrolysis. In addition, development of a microbead-conjugated DRMB assay amenable to flow cytometric analysis further advances its application. Our studies establish an analytical platform capable of evaluating the enzyme activity of select DNA repair proteins in an effort to design and guide inhibitor development and precision cancer therapy options.
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Affiliation(s)
- Jianfeng Li
- University of South Alabama Mitchell Cancer Institute, Mobile, AL, USA
| | - David Svilar
- Department of Pharmacology & Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA.,University of Pittsburgh Cancer Institute, Hillman Cancer Center, Pittsburgh, PA, USA
| | - Steven McClellan
- University of South Alabama Mitchell Cancer Institute, Mobile, AL, USA
| | - Jung-Hyun Kim
- University of South Alabama Mitchell Cancer Institute, Mobile, AL, USA
| | | | - Conchita Vens
- The Netherlands Cancer Institute, Division of Cell Biology, Amsterdam, The Netherlands
| | - David M Wilson
- Laboratory of Molecular Gerontology, National Institute on Aging, IRP, NIH Baltimore, MD, USA
| | - Robert W Sobol
- University of South Alabama Mitchell Cancer Institute, Mobile, AL, USA.,Department of Pharmacology & Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA.,University of Pittsburgh Cancer Institute, Hillman Cancer Center, Pittsburgh, PA, USA
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14
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Chakraborty A, Viswanathan P. Methylation-Demethylation Dynamics: Implications of Changes in Acute Kidney Injury. Anal Cell Pathol (Amst) 2018. [DOI: https://doi.org/10.1155/2018/8764384] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Over the years, the epigenetic landscape has grown increasingly complex. Until recently, methylation of DNA and histones was considered one of the most important epigenetic modifications. However, with the discovery of enzymes involved in the demethylation process, several exciting prospects have emerged that focus on the dynamic regulation of methylation and its crucial role in development and disease. An interplay of the methylation-demethylation machinery controls the process of gene expression. Since acute kidney injury (AKI), a major risk factor for chronic kidney disease and death, is characterised by aberrant expression of genes, understanding the dynamics of methylation and demethylation will provide new insights into the intricacies of the disease. Research on epigenetics in AKI has only made its mark in the recent years but has provided compelling evidence that implicates the involvement of methylation and demethylation changes in its pathophysiology. In this review, we explore the role of methylation and demethylation machinery in cellular epigenetic control and further discuss the contribution of methylomic changes and histone modifications to the pathophysiology of AKI.
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Affiliation(s)
- Anubhav Chakraborty
- Renal Research Lab, Centre for Bio-Medical Research, School of Bio-Sciences and Technology, Vellore Institute of Technology, Vellore 632014, India
| | - Pragasam Viswanathan
- Renal Research Lab, Centre for Bio-Medical Research, School of Bio-Sciences and Technology, Vellore Institute of Technology, Vellore 632014, India
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15
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Outlier response to anti-PD1 in uveal melanoma reveals germline MBD4 mutations in hypermutated tumors. Nat Commun 2018; 9:1866. [PMID: 29760383 PMCID: PMC5951831 DOI: 10.1038/s41467-018-04322-5] [Citation(s) in RCA: 88] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2017] [Accepted: 04/19/2018] [Indexed: 12/13/2022] Open
Abstract
Metastatic uveal melanoma is a deadly disease with no proven standard of care. Here we present a metastatic uveal melanoma patient with an exceptional high sensitivity to a PD-1 inhibitor associated with outlier CpG>TpG mutation burden, MBD4 germline deleterious mutation, and somatic MBD4 inactivation in the tumor. We identify additional tumors in The Cancer Genome Atlas (TCGA) cohorts with similar hypermutator profiles in patients carrying germline deleterious MBD4 mutations and somatic loss of heterozygosity. This MBD4-related hypermutator phenotype may explain unexpected responses to immune checkpoint inhibitors. Hypermutated tumors respond more favorably to checkpoint inhibitor-based immune therapy. Here, the authors describe a new hypermutated phenotype due to germline mutations and subsequent somatic loss of heterozygosity of MBD4, and a dramatic response to the PD-1 inhibitor pembrolizumab in a patient with a MBD4-inactivated hypermutated uveal melanoma.
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16
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Chakraborty A, Viswanathan P. Methylation-Demethylation Dynamics: Implications of Changes in Acute Kidney Injury. Anal Cell Pathol (Amst) 2018; 2018:8764384. [PMID: 30073137 PMCID: PMC6057397 DOI: 10.1155/2018/8764384] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2018] [Revised: 06/05/2018] [Accepted: 06/14/2018] [Indexed: 02/05/2023] Open
Abstract
Over the years, the epigenetic landscape has grown increasingly complex. Until recently, methylation of DNA and histones was considered one of the most important epigenetic modifications. However, with the discovery of enzymes involved in the demethylation process, several exciting prospects have emerged that focus on the dynamic regulation of methylation and its crucial role in development and disease. An interplay of the methylation-demethylation machinery controls the process of gene expression. Since acute kidney injury (AKI), a major risk factor for chronic kidney disease and death, is characterised by aberrant expression of genes, understanding the dynamics of methylation and demethylation will provide new insights into the intricacies of the disease. Research on epigenetics in AKI has only made its mark in the recent years but has provided compelling evidence that implicates the involvement of methylation and demethylation changes in its pathophysiology. In this review, we explore the role of methylation and demethylation machinery in cellular epigenetic control and further discuss the contribution of methylomic changes and histone modifications to the pathophysiology of AKI.
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Affiliation(s)
- Anubhav Chakraborty
- Renal Research Lab, Centre for Bio-Medical Research, School of Bio-Sciences and Technology, Vellore Institute of Technology, Vellore 632014, India
| | - Pragasam Viswanathan
- Renal Research Lab, Centre for Bio-Medical Research, School of Bio-Sciences and Technology, Vellore Institute of Technology, Vellore 632014, India
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17
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Rodríguez-Rodero S, Delgado-Álvarez E, Díaz-Naya L, Martín Nieto A, Menéndez Torre E. Epigenetic modulators of thyroid cancer. ACTA ACUST UNITED AC 2017; 64:44-56. [PMID: 28440770 DOI: 10.1016/j.endinu.2016.09.006] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2016] [Revised: 09/14/2016] [Accepted: 09/20/2016] [Indexed: 12/14/2022]
Abstract
There are some well known factors involved in the etiology of thyroid cancer, including iodine deficiency, radiation exposure at early ages, or some genetic changes. However, epigenetic modulators that may contribute to development of these tumors and be helpful to for both their diagnosis and treatment have recently been discovered. The currently known changes in DNA methylation, histone modifications, and non-coding RNAs in each type of thyroid carcinoma are reviewed here.
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Affiliation(s)
- Sandra Rodríguez-Rodero
- Department of Endocrinology and Nutrition, Hospital Universitario Central de Asturias (HUCA), Oviedo, Asturias, Spain; Cancer Epigenetics Laboratory, Institute of Oncology of Asturias (IUOPA), HUCA, Universidad de Oviedo, Oviedo, Spain
| | - Elías Delgado-Álvarez
- Department of Endocrinology and Nutrition, Hospital Universitario Central de Asturias (HUCA), Oviedo, Asturias, Spain
| | - Lucía Díaz-Naya
- Department of Endocrinology and Nutrition, Hospital Universitario Central de Asturias (HUCA), Oviedo, Asturias, Spain
| | - Alicia Martín Nieto
- Department of Endocrinology and Nutrition, Hospital Universitario Central de Asturias (HUCA), Oviedo, Asturias, Spain
| | - Edelmiro Menéndez Torre
- Department of Endocrinology and Nutrition, Hospital Universitario Central de Asturias (HUCA), Oviedo, Asturias, Spain.
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18
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Ng HZ, Ng M, Eng CM, Gao Z. Deoxyribonucleic acid glycosylase assays: Progress and prospects. Trends Analyt Chem 2016. [DOI: 10.1016/j.trac.2016.08.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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19
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Milan M, Matozzo V, Pauletto M, Di Camillo B, Giacomazzo M, Boffo L, Binato G, Marin MG, Patarnello T, Bargelloni L. Can ecological history influence response to pollutants? Transcriptomic analysis of Manila clam collected in different Venice lagoon areas and exposed to heavy metal. AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2016; 174:123-133. [PMID: 26945539 DOI: 10.1016/j.aquatox.2016.02.024] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/04/2015] [Revised: 02/26/2016] [Accepted: 02/27/2016] [Indexed: 06/05/2023]
Abstract
Chronic exposure to environmental pollutants can exert strong selective pressures on natural populations, favoring the transmission over generations of traits that enable individuals to survive and thrive in highly impacted environments. The lagoon of Venice is an ecosystem subject to heavy anthropogenic impact, mainly due to the industrial activities of Porto Marghera (PM), which led to a severe chemical contamination of soil, groundwater, and sediments. Gene expression analysis on wild Manila clams collected in different Venice lagoon areas enabled to identify differences in gene expression profiles between clams collected in PM and those sampled in clean areas, and the definition of molecular signatures of chemical stress. However, it remains largely unexplored to which extent modifications of gene expression patterns persists after removing the source of contamination. It is also relatively unknown whether chronic exposure to xenobiotics affects the response to other chemical pollutants. To start exploring such issues, in the present study a common-garden experiment was coupled with transcriptomic analysis, to compare gene expression profiles of PM clams with those of clams collected in the less impacted area of Chioggia (CH) during a period under the same control conditions. Part of the two experimental groups were also exposed to copper for seven days to assess whether different "ecological history" does influence response to such pollutant. The results obtained suggest that the chronic exposure to chemical pollution generated a response at the transcriptional level that persists after removal for the contaminated site. These transcriptional changes are centered on key biological processes, such as defense against either oxidative stress or tissue/protein damage, and detoxification, suggesting an adaptive strategy for surviving in the deeply impacted environment of Porto Marghera. On the other hand, CH clams appeared to respond more effectively to copper exposure than PM animals, proposing that chronic exposure to chemical toxicants either lowers the sensitivity to additional toxicants or blunts the capacity to respond to novel chemical challenges in PM clams.
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Affiliation(s)
- Massimo Milan
- Department of Comparative Biomedicine and Food Science, University of Padova, 35020, Legnaro, Italy.
| | - Valerio Matozzo
- Department of Biology, University of Padova, via G. Colombo 3, 35131 Padova, Italy
| | - Marianna Pauletto
- Department of Comparative Biomedicine and Food Science, University of Padova, 35020, Legnaro, Italy
| | | | - Matteo Giacomazzo
- Department of Biology, University of Padova, via G. Colombo 3, 35131 Padova, Italy; Department of Environmental Sciences University of Quèbec at Trois-Rivières, Canada
| | | | - Giovanni Binato
- Laboratory of Chemistry, Istituto Zooprofilattico Sperimentale delle Venezie, Legnaro, Italy
| | | | - Tomaso Patarnello
- Department of Comparative Biomedicine and Food Science, University of Padova, 35020, Legnaro, Italy
| | - Luca Bargelloni
- Department of Comparative Biomedicine and Food Science, University of Padova, 35020, Legnaro, Italy
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20
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Xu X, Watt DS, Liu C. Multifaceted roles for thymine DNA glycosylase in embryonic development and human carcinogenesis. Acta Biochim Biophys Sin (Shanghai) 2016; 48:82-9. [PMID: 26370152 DOI: 10.1093/abbs/gmv083] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2015] [Accepted: 07/12/2015] [Indexed: 01/03/2023] Open
Abstract
Thymine DNA glycosylase (TDG) is a multifunctional protein that plays important roles in DNA repair, DNA demethylation, and transcriptional regulation. These diverse functions make TDG a unique enzyme in embryonic development and carcinogenesis. This review discusses the molecular function of TDG in human cancers and the previously unrecognized value of TDG as a potential target for drug therapy.
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Affiliation(s)
- Xuehe Xu
- Department of Molecular and Cellular Biochemistry, Markey Cancer Center, University of Kentucky, Lexington, KY 40536-0509, USA
| | - David S Watt
- Department of Molecular and Cellular Biochemistry, Markey Cancer Center, University of Kentucky, Lexington, KY 40536-0509, USA
| | - Chunming Liu
- Department of Molecular and Cellular Biochemistry, Markey Cancer Center, University of Kentucky, Lexington, KY 40536-0509, USA
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21
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Lenz SAP, Kellie JL, Wetmore SD. Glycosidic Bond Cleavage in DNA Nucleosides: Effect of Nucleobase Damage and Activation on the Mechanism and Barrier. J Phys Chem B 2015; 119:15601-12. [PMID: 26618397 DOI: 10.1021/acs.jpcb.5b10337] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Stefan A. P. Lenz
- Department of Chemistry and
Biochemistry, University of Lethbridge, 4401 University Drive West, Lethbridge, Alberta T1K 3M4, Canada
| | - Jennifer L. Kellie
- Department of Chemistry and
Biochemistry, University of Lethbridge, 4401 University Drive West, Lethbridge, Alberta T1K 3M4, Canada
| | - Stacey D. Wetmore
- Department of Chemistry and
Biochemistry, University of Lethbridge, 4401 University Drive West, Lethbridge, Alberta T1K 3M4, Canada
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22
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Bauer NC, Corbett AH, Doetsch PW. The current state of eukaryotic DNA base damage and repair. Nucleic Acids Res 2015; 43:10083-101. [PMID: 26519467 PMCID: PMC4666366 DOI: 10.1093/nar/gkv1136] [Citation(s) in RCA: 104] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2015] [Accepted: 10/16/2015] [Indexed: 12/15/2022] Open
Abstract
DNA damage is a natural hazard of life. The most common DNA lesions are base, sugar, and single-strand break damage resulting from oxidation, alkylation, deamination, and spontaneous hydrolysis. If left unrepaired, such lesions can become fixed in the genome as permanent mutations. Thus, evolution has led to the creation of several highly conserved, partially redundant pathways to repair or mitigate the effects of DNA base damage. The biochemical mechanisms of these pathways have been well characterized and the impact of this work was recently highlighted by the selection of Tomas Lindahl, Aziz Sancar and Paul Modrich as the recipients of the 2015 Nobel Prize in Chemistry for their seminal work in defining DNA repair pathways. However, how these repair pathways are regulated and interconnected is still being elucidated. This review focuses on the classical base excision repair and strand incision pathways in eukaryotes, considering both Saccharomyces cerevisiae and humans, and extends to some important questions and challenges facing the field of DNA base damage repair.
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Affiliation(s)
- Nicholas C Bauer
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA 30322, USA Graduate Program in Biochemistry, Cell, and Developmental Biology, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Anita H Corbett
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA 30322, USA Winship Cancer Institute, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Paul W Doetsch
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA 30322, USA Winship Cancer Institute, Emory University School of Medicine, Atlanta, GA 30322, USA Department of Radiation Oncology, Emory University School of Medicine, Atlanta, GA 30322, USA Department of Hematology and Medical Oncology, Emory University School of Medicine, Atlanta, GA 30322, USA
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23
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Do H, Dobrovic A. Sequence Artifacts in DNA from Formalin-Fixed Tissues: Causes and Strategies for Minimization. Clin Chem 2015; 61:64-71. [DOI: 10.1373/clinchem.2014.223040] [Citation(s) in RCA: 331] [Impact Index Per Article: 36.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Abstract
BACKGROUND
Precision medicine is dependent on identifying actionable mutations in tumors. Accurate detection of mutations is often problematic in formalin-fixed paraffin-embedded (FFPE) tissues. DNA extracted from formalin-fixed tissues is fragmented and also contains DNA lesions that are the sources of sequence artifacts. Sequence artifacts can be difficult to distinguish from true mutations, especially in the context of tumor heterogeneity, and are an increasing interpretive problem in this era of massively parallel sequencing. Understanding of the sources of sequence artifacts in FFPE tissues and implementation of preventative strategies are critical to improve the accurate detection of actionable mutations.
CONTENT
This mini-review focuses on DNA template lesions in FFPE tissues as the source of sequence artifacts in molecular analysis. In particular, fragmentation, base modification (including uracil and thymine deriving from cytosine deamination), and abasic sites are discussed as indirect or direct sources of sequence artifacts. We discuss strategies that can be implemented to minimize sequence artifacts and to distinguish true mutations from sequence artifacts. These strategies are applicable for the detection of actionable mutations in both single amplicon and massively parallel amplicon sequencing approaches.
SUMMARY
Because FFPE tissues are usually the only available material for DNA analysis, it is important to maximize the accurate informational content from FFPE DNA. Careful consideration of each step in the work flow is needed to minimize sequence artifacts. In addition, validation of actionable mutations either by appropriate experimental design or by orthogonal methods should be considered.
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Affiliation(s)
- Hongdo Do
- Translational Genomics and Epigenomics Laboratory, Olivia Newton-John Cancer Research Institute, Heidelberg, Victoria, Australia
- Department of Pathology, University of Melbourne, Parkville, Victoria, Australia
- School of Cancer Medicine, La Trobe University, Bundoora, Victoria, Australia
| | - Alexander Dobrovic
- Translational Genomics and Epigenomics Laboratory, Olivia Newton-John Cancer Research Institute, Heidelberg, Victoria, Australia
- Department of Pathology, University of Melbourne, Parkville, Victoria, Australia
- School of Cancer Medicine, La Trobe University, Bundoora, Victoria, Australia
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24
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Perevozchikova SA, Trikin RM, Heinze RJ, Romanova EA, Oretskaya TS, Friedhoff P, Kubareva EA. Is thymidine glycol containing DNA a substrate of E. coli DNA mismatch repair system? PLoS One 2014; 9:e104963. [PMID: 25133614 PMCID: PMC4136841 DOI: 10.1371/journal.pone.0104963] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2014] [Accepted: 07/15/2014] [Indexed: 11/18/2022] Open
Abstract
The DNA mismatch repair (MMR) system plays a crucial role in the prevention of replication errors and in the correction of some oxidative damages of DNA bases. In the present work the most abundant oxidized pyrimidine lesion, 5,6-dihydro-5,6-dihydroxythymidine (thymidine glycol, Tg) was tested for being recognized and processed by the E. coli MMR system, namely complex of MutS, MutL and MutH proteins. In a partially reconstituted MMR system with MutS-MutL-MutH proteins, G/Tg and A/Tg containing plasmids failed to provoke the incision of DNA. Tg residue in the 30-mer DNA duplex destabilized double helix due to stacking disruption with neighboring bases. However, such local structural changes are not important for E. coli MMR system to recognize this lesion. A lack of repair of Tg containing DNA could be due to a failure of MutS (a first acting protein of MMR system) to interact with modified DNA in a proper way. It was shown that Tg in DNA does not affect on ATPase activity of MutS. On the other hand, MutS binding affinities to DNA containing Tg in G/Tg and A/Tg pairs are lower than to DNA with a G/T mismatch and similar to canonical DNA. Peculiarities of MutS interaction with DNA was monitored by Förster resonance energy transfer (FRET) and fluorescence anisotropy. Binding of MutS to Tg containing DNAs did not result in the formation of characteristic DNA kink. Nevertheless, MutS homodimer orientation on Tg-DNA is similar to that in the case of G/T-DNA. In contrast to G/T-DNA, neither G/Tg- nor A/Tg-DNA was able to stimulate ADP release from MutS better than canonical DNA. Thus, Tg residue in DNA is unlikely to be recognized or processed by the E. coli MMR system. Probably, the MutS transformation to active “sliding clamp” conformation on Tg-DNA is problematic.
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Affiliation(s)
- Svetlana A. Perevozchikova
- Department of Chemistry and Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, Russia
| | - Roman M. Trikin
- Institute of Cell Biology, University of Bern, Bern, Switzerland
| | - Roger J. Heinze
- Institute for Biochemistry, Justus Liebig University, Giessen, Germany
| | - Elena A. Romanova
- Department of Chemistry and Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, Russia
| | - Tatiana S. Oretskaya
- Department of Chemistry and Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, Russia
| | - Peter Friedhoff
- Institute for Biochemistry, Justus Liebig University, Giessen, Germany
| | - Elena A. Kubareva
- Department of Chemistry and Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, Russia
- * E-mail:
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25
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Talhaoui I, Couve S, Gros L, Ishchenko AA, Matkarimov B, Saparbaev MK. Aberrant repair initiated by mismatch-specific thymine-DNA glycosylases provides a mechanism for the mutational bias observed in CpG islands. Nucleic Acids Res 2014; 42:6300-13. [PMID: 24692658 PMCID: PMC4041421 DOI: 10.1093/nar/gku246] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2013] [Revised: 03/09/2014] [Accepted: 03/13/2014] [Indexed: 12/13/2022] Open
Abstract
The human thymine-DNA glycosylase (TDG) initiates the base excision repair (BER) pathway to remove spontaneous and induced DNA base damage. It was first biochemically characterized for its ability to remove T mispaired with G in CpG context. TDG is involved in the epigenetic regulation of gene expressions by protecting CpG-rich promoters from de novo DNA methylation. Here we demonstrate that TDG initiates aberrant repair by excising T when it is paired with a damaged adenine residue in DNA duplex. TDG targets the non-damaged DNA strand and efficiently excises T opposite of hypoxanthine (Hx), 1,N(6)-ethenoadenine, 7,8-dihydro-8-oxoadenine and abasic site in TpG/CpX context, where X is a modified residue. In vitro reconstitution of BER with duplex DNA containing Hx•T pair and TDG results in incorporation of cytosine across Hx. Furthermore, analysis of the mutation spectra inferred from single nucleotide polymorphisms in human population revealed a highly biased mutation pattern within CpG islands (CGIs), with enhanced mutation rate at CpA and TpG sites. These findings demonstrate that under experimental conditions used TDG catalyzes sequence context-dependent aberrant removal of thymine, which results in TpG, CpA→CpG mutations, thus providing a plausible mechanism for the putative evolutionary origin of the CGIs in mammalian genomes.
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Affiliation(s)
- Ibtissam Talhaoui
- Groupe Réparation de l’ADN, Université Paris Sud, Laboratoire Stabilité Génétique et Oncogenèse CNRS, UMR 8200, Gustave Roussy, F-94805 Villejuif Cedex, France
| | - Sophie Couve
- Laboratoire de Génétique Oncologique EPHE, INSERM U753, Gustave Roussy, F-94805 Villejuif, France
| | - Laurent Gros
- Groupe Réparation de l’ADN, Université Paris Sud, Laboratoire Stabilité Génétique et Oncogenèse CNRS, UMR 8200, Gustave Roussy, F-94805 Villejuif Cedex, France
- AB Science SA, 75008 Paris, France
| | - Alexander A. Ishchenko
- Groupe Réparation de l’ADN, Université Paris Sud, Laboratoire Stabilité Génétique et Oncogenèse CNRS, UMR 8200, Gustave Roussy, F-94805 Villejuif Cedex, France
| | - Bakhyt Matkarimov
- Nazarbayev University Research and Innovation System, Astana 010000, Kazakhstan
| | - Murat K. Saparbaev
- Groupe Réparation de l’ADN, Université Paris Sud, Laboratoire Stabilité Génétique et Oncogenèse CNRS, UMR 8200, Gustave Roussy, F-94805 Villejuif Cedex, France
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Li S, Yang J. System analysis of synonymous codon usage biases in archaeal virus genomes. J Theor Biol 2014; 355:128-39. [PMID: 24685889 PMCID: PMC7094158 DOI: 10.1016/j.jtbi.2014.03.022] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2013] [Revised: 03/11/2014] [Accepted: 03/12/2014] [Indexed: 12/30/2022]
Abstract
Recent studies of geothermally heated aquatic ecosystems have found widely divergent viruses with unusual morphotypes. Archaeal viruses isolated from these hot habitats usually have double-stranded DNA genomes, linear or circular, and can infect members of the Archaea domain. In this study, the synonymous codon usage bias (SCUB) and dinucleotide composition in the available complete archaeal virus genome sequences have been investigated. It was found that there is a significant variation in SCUB among different Archaeal virus species, which is mainly determined by the base composition. The outcome of correspondence analysis (COA) and Spearman׳s rank correlation analysis shows that codon usage of selected archaeal virus genes depends mainly on GC richness of genome, and the gene׳s function, albeit with smaller effects, also contributes to codon usage in this virus. Furthermore, this investigation reveals that aromaticity of each protein is also critical in affecting SCUB of these viral genes although it was less important than that of the mutational bias. Especially, mutational pressure may influence SCUB in SIRV1, SIRV2, ARV1, AFV1, and PhiCh1 viruses, whereas translational selection could play a leading role in HRPV1׳s SCUB. These conclusions not only can offer an insight into the codon usage biases of archaeal virus and subsequently the possible relationship between archaeal viruses and their host, but also may help in understanding the evolution of archaeal viruses and their gene classification, and more helpful to explore the origin of life and the evolution of biology. The SCUB of archaeal virus genes depends mainly on GC richness of genome. The mutational pressure is the main factor that influences SCUB. The aromaticity of each protein is also critical in affecting SCUB. The translational selection could play a leading role in HRPV1׳s SCUB. The mode is helpful to explore the origin of life and the evolution of biology.
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Affiliation(s)
- Sen Li
- State Key Laboratory of Pharmaceutical Biotechnology, School of Life Science, Nanjing University, Nanjing 210093, China
| | - Jie Yang
- State Key Laboratory of Pharmaceutical Biotechnology, School of Life Science, Nanjing University, Nanjing 210093, China.
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27
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Lan L, Nakajima S, Wei L, Sun L, Hsieh CL, Sobol RW, Bruchez M, Van Houten B, Yasui A, Levine AS. Novel method for site-specific induction of oxidative DNA damage reveals differences in recruitment of repair proteins to heterochromatin and euchromatin. Nucleic Acids Res 2013; 42:2330-45. [PMID: 24293652 PMCID: PMC3936713 DOI: 10.1093/nar/gkt1233] [Citation(s) in RCA: 76] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Reactive oxygen species (ROS)-induced DNA damage is repaired by the base excision repair pathway. However, the effect of chromatin structure on BER protein recruitment to DNA damage sites in living cells is poorly understood. To address this problem, we developed a method to specifically produce ROS-induced DNA damage by fusing KillerRed (KR), a light-stimulated ROS-inducer, to a tet-repressor (tetR-KR) or a transcription activator (TA-KR). TetR-KR or TA-KR, bound to a TRE cassette (∼90 kb) integrated at a defined genomic locus in U2OS cells, was used to induce ROS damage in hetero- or euchromatin, respectively. We found that DNA glycosylases were efficiently recruited to DNA damage in heterochromatin, as well as in euchromatin. PARP1 was recruited to DNA damage within condensed chromatin more efficiently than in active chromatin. In contrast, recruitment of FEN1 was highly enriched at sites of DNA damage within active chromatin in a PCNA- and transcription activation-dependent manner. These results indicate that oxidative DNA damage is differentially processed within hetero or euchromatin.
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Affiliation(s)
- Li Lan
- Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA, University of Pittsburgh Cancer Institute, University of Pittsburgh School of Medicine, 5117 Centre Avenue, Pittsburgh, PA 15213, USA, School of Medicine, Tsinghua University, No.1 Tsinghua Yuan, Haidian District, Beijing 100084, People's Republic of China, Department of Pharmacology & Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA, Department of Human Genetics, University of Pittsburgh Graduate School of Public Health, Pittsburgh, PA 15213, USA, Department of Chemistry and Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, PA 15213, USA and Division of Dynamic Proteome, Institute of Development, Aging, and Cancer, Tohoku University, Seiryomachi 4-1, Sendai 980-8575, Japan
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28
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Wu L, Zheng Q. Active demethylation of the IL-2 Promoter in CD4+ T cells is mediated by an inducible DNA glycosylase, Myh. Mol Immunol 2013; 58:38-49. [PMID: 24291244 DOI: 10.1016/j.molimm.2013.10.016] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2013] [Revised: 10/23/2013] [Accepted: 10/29/2013] [Indexed: 11/17/2022]
Abstract
Epigenetic control of tissue-specific gene expression is often achieved by active demethylation of promoter regions; however, the nature of all the enzymes mediating this remodeling process is not fully clear. Here we describe a 5-methylcytosine glycosylase activity for the murine DNA base excision repair enzyme Myh and show that it is critically involved in remodeling the IL-2 Promoter for transcription. The enzyme is not expressed in naïve CD4(+) T cells, but can be transiently induced following T cell activation. T cells deficient in Myh had blunted demethylation of the promoter and impaired IL-2 secretion but not IFN-γ. An in vitro assay for the glycosylase activity revealed the enzyme to be sequence specific for certain CpG sites in the IL-2 Promoter. These results suggest that DNA demethylation is being selectively used to orchestrate a part of the naïve CD4(+) T cell differentiation program.
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Affiliation(s)
- Liangtang Wu
- Kelly Services, Inc., 1 Church Street, Suite 304, Rockville, MD 20850, USA; Department of Pharmacology, University of Illinois at Chicago, 835 S. Wolcott Street, Chicago, IL 60616, USA.
| | - Quan Zheng
- Kelly Services, Inc., 1 Church Street, Suite 304, Rockville, MD 20850, USA
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29
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Pagano G, Talamanca AA, Castello G, d'Ischia M, Pallardó FV, Petrović S, Porto B, Tiano L, Zatterale A. Bone marrow cell transcripts from Fanconi anaemia patients reveal in vivo alterations in mitochondrial, redox and DNA repair pathways. Eur J Haematol 2013; 91:141-51. [PMID: 23646927 DOI: 10.1111/ejh.12131] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/29/2013] [Indexed: 12/14/2022]
Abstract
Fanconi anaemia (FA) is a genetic cancer predisposition disorder associated with cytogenetic instability, bone marrow failure and a pleiotropic cellular phenotype, including low thresholds of responses to oxidative stress, cross-linking agents and selected cytokines. This study was aimed at defining the scope of abnormalities in gene expression using the publicly available FA Transcriptome Consortium (FTC) database (Gene Expression Omnibus, 2009 and publicly available as GSE16334). We evaluated the data set that included transcriptomal analyses on RNA obtained from low-density bone marrow cells (BMC) from 20 patients with FA and 11 healthy volunteers, by seeking to identify changes in expression of over 22,000 genes, including a set of genes involved in: (i) bioenergetic pathways; (ii) antioxidant activities; (iii) response to stress and metal-chelating proteins; (iv) inflammation-related cytokines and (v) DNA repair. Ontological analysis of genes expressed at magnitudes of 1.5-fold or greater demonstrated significant suppression of genes in the categories of (i) energy metabolism; (ii) antioxidant activities; and (iii) stress and chelating proteins. Enhanced expression was found for 16 of 26 genes encoding inflammatory cytokines. A set of 20 of 21 transcripts for DNA repair activities were down-regulated; four of these transcripts related to type II topoisomerase. The data provide evidence for alterations in gene regulation of bioenergetic activities, redox-related activities, stress and metal-chelating proteins, and of some selected DNA repair activities in patients with FA.
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Affiliation(s)
- Giovanni Pagano
- Italian National Cancer Institute, G Pascale Foundation, CROM, Mercogliano, AV, Italy.
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30
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Talhaoui I, Couvé S, Ishchenko AA, Kunz C, Schär P, Saparbaev M. 7,8-Dihydro-8-oxoadenine, a highly mutagenic adduct, is repaired by Escherichia coli and human mismatch-specific uracil/thymine-DNA glycosylases. Nucleic Acids Res 2012. [PMID: 23209024 PMCID: PMC3553953 DOI: 10.1093/nar/gks1149] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Hydroxyl radicals predominantly react with the C8 of purines forming 7,8-dihydro-8-oxoguanine (8oxoG) and 7,8-dihydro-8-oxoadenine (8oxoA) adducts, which are highly mutagenic in mammalian cells. The majority of oxidized DNA bases are removed by DNA glycosylases in the base excision repair pathway. Here, we report for the first time that human thymine-DNA glycosylase (hTDG) and Escherichia coli mismatch-specific uracil-DNA glycosylase (MUG) can remove 8oxoA from 8oxoA•T, 8oxoA•G and 8oxoA•C pairs. Comparison of the kinetic parameters of the reaction indicates that full-length hTDG excises 8oxoA, 3,N4-ethenocytosine (εC) and T with similar efficiency (kmax = 0.35, 0.36 and 0.16 min−1, respectively) and is more proficient as compared with its bacterial homologue MUG. The N-terminal domain of the hTDG protein is essential for 8oxoA–DNA glycosylase activity, but not for εC repair. Interestingly, the TDG status had little or no effect on the proliferation rate of mouse embryonic fibroblasts after exposure to γ-irradiation. Nevertheless, using whole cell-free extracts from the DNA glycosylase-deficient murine embryonic fibroblasts and E. coli, we demonstrate that the excision of 8oxoA from 8oxoA•T and 8oxoA•G has an absolute requirement for TDG and MUG, respectively. The data establish that MUG and TDG can counteract the genotoxic effects of 8oxoA residues in vivo.
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Affiliation(s)
- Ibtissam Talhaoui
- Groupe Réparation de l'ADN, Université Paris Sud, Laboratoire Stabilité Génétique et Oncogenèse CNRS, UMR 8200, Institut de Cancérologie Gustave Roussy, F-94805 Villejuif Cedex, France
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31
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Qu W, Hashimoto SI, Shimada A, Nakatani Y, Ichikawa K, Saito TL, Ogoshi K, Matsushima K, Suzuki Y, Sugano S, Takeda H, Morishita S. Genome-wide genetic variations are highly correlated with proximal DNA methylation patterns. Genome Res 2012; 22:1419-25. [PMID: 22689467 PMCID: PMC3409255 DOI: 10.1101/gr.140236.112] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
5-methyl-cytosines at CpG sites frequently mutate into thymines, accounting for a large proportion of spontaneous point mutations. The repair system would leave substantial numbers of errors in neighboring regions if the synthesis of erased gaps around deaminated 5-methyl-cytosines is error-prone. Indeed, we identified an unexpected genome-wide role of the CpG methylation state as a major determinant of proximal natural genetic variation. Specifically, 507 Mbp (∼18%) of the human genome was within 10 bp of a CpG site; in these regions, the single nucleotide polymorphism (SNP) rate significantly increased by ∼50% (P < 10−566 by a two-proportion z-test) if the neighboring CpG sites are methylated. To reconfirm this finding in another vertebrate, we compared six single-base resolution methylomes in two inbred medaka (Oryzias latipes) strains with sufficient genetic divergence (3.4%). We found that the SNP rate also increased by ∼50% (P < 10−2170), and the substitution rates in all dinucleotides increased simultaneously (P < 10−441) around methylated CpG sites. In the hypomethylated regions, the “CGCG” motif was significantly enriched (P < 10−680) and evolutionarily conserved (P = ∼ 0.203%), and slow CpG deamination rather than fast CpG gain was seen, indicating a possible role of CGCG as a candidate cis-element for the hypomethylation state. In regions that were hypermethylated in germline-like tissues but were hypomethylated in somatic liver cells, the SNP rate was significantly smaller than that in hypomethylated regions in both tissues, suggesting a positive selective pressure during DNA methylation reprogramming. This is the first report of findings showing that the CpG methylation state is significantly correlated with the characteristics of evolutionary change in neighboring DNA.
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Affiliation(s)
- Wei Qu
- Department of Computational Biology, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa 277-0882, Japan.
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32
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Dinis J, Silva V, Gromicho M, Martins C, Laires A, Tavares P, Rendeiro P, Torres F, Rueff J, Rodrigues A. DNA damage response in imatinib resistant chronic myeloid leukemia K562 cells. Leuk Lymphoma 2012; 53:2004-14. [PMID: 22475343 DOI: 10.3109/10428194.2012.681654] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Resistance to imatinib in patients with chronic myeloid leukemia can lead to advanced disease and blast crisis. Conventional chemotherapy with DNA damaging agents is then used, alone or in combination with other tyrosine kinase inhibitors (TKIs). Our aim was to assess whether imatinib resistant K562 cells were also resistant to DNA damaging agents. After treatment with H(2)O(2) and doxorubicin, but not camptothecin, cell survival was higher in imatinib resistant cells compared to parental cells. DNA damage, measured by comet and γ-H2AX assays, was lower in imatinib resistant cells. mRNA expression levels of 50 genes of the DNA damage response pathway showed increased expression of the base excision repair (BER) genes MBD4 and NTHL1. Knockdown of MBD4 and NTHL1 expression in resistant cells using siRNA decreased cell survival after treatment with H(2)O(2) and doxorubicin. Our results indicate that imatinib resistant cells display cross-resistance to oxidative agents, partly through up-regulation of BER genes. Expression of these genes in imatinib resistant patients was not significantly different compared to sensitive patients. However, the strategy followed in this study could help identify chemotherapeutic agents that are more effective as alternative agents in cases of resistance to TKIs.
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Affiliation(s)
- Joana Dinis
- CIGMH Human Molecular Genetics Research Center, Department of Genetics, Faculty of Medical Sciences, Universidade Nova de Lisboa, Lisboa, Portugal
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33
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Bulgar AD, Weeks LD, Miao Y, Yang S, Xu Y, Guo C, Markowitz S, Oleinick N, Gerson SL, Liu L. Removal of uracil by uracil DNA glycosylase limits pemetrexed cytotoxicity: overriding the limit with methoxyamine to inhibit base excision repair. Cell Death Dis 2012; 3:e252. [PMID: 22237209 PMCID: PMC3270269 DOI: 10.1038/cddis.2011.135] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2011] [Revised: 11/09/2011] [Accepted: 11/09/2011] [Indexed: 01/03/2023]
Abstract
Uracil DNA glycosylase (UDG) specifically removes uracil bases from DNA, and its repair activity determines the sensitivity of the cell to anticancer agents that are capable of introducing uracil into DNA. In the present study, the participation of UDG in the response to pemetrexed-induced incorporation of uracil into DNA was studied using isogenic human tumor cell lines with or without UDG (UDG(+/+)/UDG(-/-)). UDG(-/-) cells were very sensitive to pemetrexed. Cell killing by pemetrexed was associated with genomic uracil accumulation, stalled DNA replication, and catastrophic DNA strand breaks. By contrast, UDG(+/+) cells were >10 times more resistant to pemetrexed due to the rapid removal of uracil from DNA by UDG and subsequent repair of the resultant AP sites (abasic sites) via the base excision repair (BER). The resistance to pemetrexed in UDG(+/+) cells could be reversed by the addition of methoxyamine (MX), which binds to AP sites and interrupts BER pathway. Furthermore, MX-bound AP sites induced cell death was related to their cytotoxic effect of dual inactivation of UDG and topoisomerase IIα, two genes that are highly expressed in lung cancer cells in comparison with normal cells. Thus, targeting BER-based therapy exhibits more selective cytotoxicity on cancer cells through a synthetic lethal mechanism.
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Affiliation(s)
- A D Bulgar
- Department of Medicine, Division of Hematology/Oncology, Case Western Reserve University, Cleveland, OH, USA
| | - L D Weeks
- Department of Medicine, Division of Hematology/Oncology, Case Western Reserve University, Cleveland, OH, USA
| | - Y Miao
- Department of Medicine, Division of Hematology/Oncology, Case Western Reserve University, Cleveland, OH, USA
| | - S Yang
- Case Comprehensive Cancer Center, Case Western Reserve University, 2103 Cornell Road, Cleveland, OH 44106, USA
| | - Y Xu
- Case Comprehensive Cancer Center, Case Western Reserve University, 2103 Cornell Road, Cleveland, OH 44106, USA
- Department of Chemistry, Cleveland State University, Cleveland, OH, USA
| | - C Guo
- Department of Medicine, Division of Hematology/Oncology, Case Western Reserve University, Cleveland, OH, USA
| | - S Markowitz
- Department of Medicine, Division of Hematology/Oncology, Case Western Reserve University, Cleveland, OH, USA
- Case Comprehensive Cancer Center, Case Western Reserve University, 2103 Cornell Road, Cleveland, OH 44106, USA
- Department of Chemistry, Cleveland State University, Cleveland, OH, USA
- Department of Genetics, Case Western Reserve University, Cleveland, OH, USA
| | - N Oleinick
- Case Comprehensive Cancer Center, Case Western Reserve University, 2103 Cornell Road, Cleveland, OH 44106, USA
- Department of Radiation Oncology, Case Western Reserve University, Cleveland, OH, USA
| | - S L Gerson
- Department of Medicine, Division of Hematology/Oncology, Case Western Reserve University, Cleveland, OH, USA
- Case Comprehensive Cancer Center, Case Western Reserve University, 2103 Cornell Road, Cleveland, OH 44106, USA
| | - L Liu
- Department of Medicine, Division of Hematology/Oncology, Case Western Reserve University, Cleveland, OH, USA
- Case Comprehensive Cancer Center, Case Western Reserve University, 2103 Cornell Road, Cleveland, OH 44106, USA
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Teperek-Tkacz M, Pasque V, Gentsch G, Ferguson-Smith AC. Epigenetic reprogramming: is deamination key to active DNA demethylation? Reproduction 2011; 142:621-32. [PMID: 21911441 DOI: 10.1530/rep-11-0148] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
DNA demethylation processes are important for reproduction, being central in epigenetic reprogramming during embryonic and germ cell development. While the enzymes methylating DNA have been known for many years, identification of factors capable of mediating active DNA demethylation has been challenging. Recent findings suggest that cytidine deaminases may be key players in active DNA demethylation. One of the most investigated candidates is activation-induced cytidine deaminase (AID), best known for its role in generating secondary antibody diversity in B cells. We evaluate evidence for cytidine deaminases in DNA demethylation pathways in vertebrates and discuss possible models for their targeting and activity regulation. These findings are also considered along with alternative demethylation pathways involving hydroxymethylation.
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Abstract
'Every Hour Hurts, The Last One Kills'. That is an old saying about getting old. Every day, thousands of DNA damaging events take place in each cell of our body, but efficient DNA repair systems have evolved to prevent that. However, our DNA repair system and that of most other organisms are not as perfect as that of Deinococcus radiodurans, for example, which is able to repair massive amounts of DNA damage at one time. In many instances, accumulation of DNA damage has been linked to cancer, and genetic deficiencies in specific DNA repair genes are associated with tumor-prone phenotypes. In addition to mutations, which can be either inherited or somatically acquired, epigenetic silencing of DNA repair genes may promote tumorigenesis. This review will summarize current knowledge of the epigenetic inactivation of different DNA repair components in human cancer.
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Affiliation(s)
- Christoph Lahtz
- Department of Cancer Biology, Beckman Research Institute, City of Hope, Duarte, CA 91010, USA
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36
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Svilar D, Goellner EM, Almeida KH, Sobol RW. Base excision repair and lesion-dependent subpathways for repair of oxidative DNA damage. Antioxid Redox Signal 2011; 14:2491-507. [PMID: 20649466 PMCID: PMC3096496 DOI: 10.1089/ars.2010.3466] [Citation(s) in RCA: 191] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Nuclear and mitochondrial genomes are under continuous assault by a combination of environmentally and endogenously derived reactive oxygen species, inducing the formation and accumulation of mutagenic, toxic, and/or genome-destabilizing DNA lesions. Failure to resolve these lesions through one or more DNA-repair processes is associated with genome instability, mitochondrial dysfunction, neurodegeneration, inflammation, aging, and cancer, emphasizing the importance of characterizing the pathways and proteins involved in the repair of oxidative DNA damage. This review focuses on the repair of oxidative damage-induced lesions in nuclear and mitochondrial DNA mediated by the base excision repair (BER) pathway in mammalian cells. We discuss the multiple BER subpathways that are initiated by one of 11 different DNA glycosylases of three subtypes: (a) bifunctional with an associated β-lyase activity; (b) monofunctional; and (c) bifunctional with an associated β,δ-lyase activity. These three subtypes of DNA glycosylases all initiate BER but yield different chemical intermediates and hence different BER complexes to complete repair. Additionally, we briefly summarize alternate repair events mediated by BER proteins and the role of BER in the repair of mitochondrial DNA damage induced by ROS. Finally, we discuss the relation of BER and oxidative DNA damage in the onset of human disease.
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Affiliation(s)
- David Svilar
- Department of Pharmacology & Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA
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37
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Rao X, Zhong J, Zhang S, Zhang Y, Yu Q, Yang P, Wang MH, Fulton DJ, Shi H, Dong Z, Wang D, Wang CY. Loss of methyl-CpG-binding domain protein 2 enhances endothelial angiogenesis and protects mice against hind-limb ischemic injury. Circulation 2011; 123:2964-74. [PMID: 21670230 DOI: 10.1161/circulationaha.110.966408] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND Despite intensive investigation, how DNA methylation influences endothelial function remains poorly understood. We used methyl-CpG-binding domain protein 2 (MBD2), an interpreter for DNA methylome-encoded information, to dissect the impact of DNA methylation on endothelial function in both physiological and pathophysiological states. METHODS AND RESULTS Human umbilical vein endothelial cells under normal conditions express moderate levels of MBD2, but knockdown of MBD2 by siRNA significantly enhanced angiogenesis and provided protection against H(2)O(2)-induced apoptosis. Remarkably, Mbd2(-/-) mice were protected against hind-limb ischemia evidenced by the significant improvement in perfusion recovery, along with increased capillary and arteriole formation. Loss of MBD2 activated endothelial survival and proangiogenic signals downstream of vascular endothelial growth factor signaling characterized by an increase in endothelial nitric oxide synthase (eNOS) and vascular endothelial growth factor receptor 2 expression, along with enhanced extracellular signal-regulated kinase 1/2 activation and BCL-2 expression. Mechanistic studies confirmed the methylation of CpG elements in the eNOS and vascular endothelial growth factor receptor 2 promoter. MBD2 binds to these methylated CpG elements and suppresses eNOS promoter activity. On ischemic insult, key endothelial genes such as eNOS and vascular endothelial growth factor receptor 2 undergo a DNA methylation turnover, and MBD2 interprets the changes of DNA methylation to suppress their expressions. Moreover, MBD2 modulation of eNOS expression is likely confined to endothelial cells because nonendothelial cells such as splenocytes fail to express eNOS after loss of MBD2. CONCLUSIONS We provided direct evidence supporting that DNA methylation regulates endothelial function, which forms the molecular basis for understanding how environmental insults (epigenetic factor) affect the genome to modify disease susceptibility. Because MBD2 itself does not affect the methylation of DNA and is dispensable for normal physiology in mice, it could be a viable epigenetic target for modulating endothelial function in disease states.
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Affiliation(s)
- Xiaoquan Rao
- Center for Biomedical Research, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1095 Jiefang Ave., Wuhan, China
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38
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Abstract
Chromatin is by its very nature a repressive environment which restricts the recruitment of transcription factors and acts as a barrier to polymerases. Therefore the complex process of gene activation must operate at two levels. In the first instance, localized chromatin decondensation and nucleosome displacement is required to make DNA accessible. Second, sequence-specific transcription factors need to recruit chromatin modifiers and remodellers to create a chromatin environment that permits the passage of polymerases. In this review I will discuss the chromatin structural changes that occur at active gene loci and at regulatory elements that exist as DNase I hypersensitive sites.
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Affiliation(s)
- Peter N Cockerill
- Experimental Haematology, Leeds Institute of Molecular Medicine, University of Leeds, UK.
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39
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Natural history of eukaryotic DNA methylation systems. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2011; 101:25-104. [PMID: 21507349 DOI: 10.1016/b978-0-12-387685-0.00002-0] [Citation(s) in RCA: 151] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Methylation of cytosines and adenines in DNA is a widespread epigenetic mark in both prokaryotes and eukaryotes. In eukaryotes, it has a profound influence on chromatin structure and dynamics. Recent advances in genomics and biochemistry have considerably elucidated the functions and provenance of these DNA modifications. DNA methylases appear to have emerged first in bacterial restriction-modification (R-M) systems from ancient RNA-modifying enzymes, in transitions that involved acquisition of novel catalytic residues and DNA-recognition features. DNA adenine methylases appear to have been acquired by ciliates, heterolobosean amoeboflagellates, and certain chlorophyte algae. Six distinct clades of cytosine methylases, including the DNMT1, DNMT2, and DNMT3 clades, were acquired by eukaryotes through independent lateral transfer of their precursors from bacteria or bacteriophages. In addition to these, multiple adenine and cytosine methylases were acquired by several families of eukaryotic transposons. In eukaryotes, the DNA-methylase module was often combined with distinct modified and unmodified peptide recognition domains and other modules mediating specialized interactions, for example, the RFD module of DNMT1 which contains a permuted Sm domain linked to a helix-turn-helix domain. In eukaryotes, the evolution of DNA methylases appears to have proceeded in parallel to the elaboration of histone-modifying enzymes and the RNAi system, with functions related to counter-viral and counter-transposon defense, and regulation of DNA repair and differential gene expression being their primary ancestral functions. Diverse DNA demethylation systems that utilize base-excision repair via DNA glycosylases and cytosine deaminases appear to have emerged in multiple eukaryotic lineages. Comparative genomics suggests that the link between cytosine methylation and DNA glycosylases probably emerged first in a novel R-M system in bacteria. Recent studies suggest that the 5mC is not a terminal DNA modification, with enzymes of the Tet/JBP family of 2-oxoglutarate- and iron-dependent dioxygenases further hydroxylating it to form 5-hydroxymethylcytosine (5hmC). These enzymes emerged first in bacteriophages and appear to have been transferred to eukaryotes on one or more occasions. Eukaryotes appear to have recruited three major types of DNA-binding domains (SRA/SAD, TAM/MBD, and CXXC) in discriminating DNA with methylated or unmethylated cytosines. Analysis of the domain architectures of these domains and the DNA methylases suggests that early in eukaryotic evolution they developed a close functional link with SET-domain methylases and Jumonji-related demethylases that operate on peptides in chromatin proteins. In several eukaryotes, other functional connections were elaborated in the form of various combinations between domains related to DNA methylation and those involved in ATP-dependent chromatin remodeling and RNAi. In certain eukaryotes, such as mammals and angiosperms, novel dependencies on the DNA methylation system emerged, which resulted in it affecting unexpected aspects of the biology of these organisms such as parent-offspring interactions. In genomic terms, this was reflected in the emergence of new proteins related to methylation, such as Stella. The well-developed methylation systems of certain heteroloboseans, stramenopiles, chlorophytes, and haptophyte indicate that these might be new model systems to explore the relevance of DNA modifications in eukaryotes.
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Li SY, Zhang XY, Zhang X, Lan Y, Hua ZC. A convenient fluorescent-labeled assay for in vitro measurement of DNA mismatch repair activity. BIOMEDICAL AND ENVIRONMENTAL SCIENCES : BES 2010; 23:496-501. [PMID: 21315249 DOI: 10.1016/s0895-3988(11)60013-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/22/2010] [Accepted: 09/17/2010] [Indexed: 05/30/2023]
Abstract
OBJECTIVE The assay of DNA mismatch repair (MMR) activity can be used as a biomarker for environmental condition detection and human disease diagnosis. Radioactive ³²P-endlabeled DNA containing mismatch is extensively used as the substrate for MMR activity analyses. The aim of the present study is to develop a simple non-radioactive, but equally specific and sensitive method for the MMR activity assay. METHODS A fluorescent label was chosen to replace the radioactive isotope label. Sensitive evaluation of the fluorescent label was carried out for the first time, and then the fluorescent label was compared with the isotope label in the MMR activity and DNA binding assays. RESULT LOD (limit of detection) of the fluorescent label was about 0.1 fmol and the relative signal strength displayed a pretty good linear relationship. Moreover, the fluorescent label method has equivalent sensitivity and performance as compared with the classical radioactive method in experiments. CONCLUSION In light of the sensitivity, reproducibility, safety, rapidity and long lifespan of the fluorescent label, this improved method can be applied to evaluation of biologic and toxic effects of environmental pollutants on man and other forms of life.
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Affiliation(s)
- Shi-Ying Li
- The State Key Laboratory of Pharmaceutical Biotechnology and Jiangsu Center of Hepatobiliary Diseases, School of Stomatology and Affiliated Stomatological Hospital, Nanjing University, Nanjing 210093, Jiangsu, China
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Khrustalev VV, Barkovsky EV. Study of completed archaeal genomes and proteomes: hypothesis of strong mutational AT pressure existed in their common predecessor. GENOMICS PROTEOMICS & BIOINFORMATICS 2010; 8:22-32. [PMID: 20451159 PMCID: PMC5054120 DOI: 10.1016/s1672-0229(10)60003-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The number of completely sequenced archaeal genomes has been sufficient for a large-scale bioinformatic study. We have conducted analyses for each coding region from 36 archaeal genomes using the original CGS algorithm by calculating the total GC content (G+C), GC content in first, second and third codon positions as well as in fourfold and twofold degenerated sites from third codon positions, levels of arginine codon usage (Arg2: AGA/G; Arg4: CGX), levels of amino acid usage and the entropy of amino acid content distribution. In archaeal genomes with strong GC pressure, arginine is coded preferably by GC-rich Arg4 codons, whereas in most of archaeal genomes with G+C<0.6, arginine is coded preferably by AT-rich Arg2 codons. In the genome of Haloquadratum walsbyi, which is closely related to GC-rich archaea, GC content has decreased mostly in third codon positions, while Arg4>>Arg2 bias still persists. Proteomes of archaeal species carry characteristic amino acid biases: levels of isoleucine and lysine are elevated, while levels of alanine, histidine, glutamine and cytosine are relatively decreased. Numerous genomic and proteomic biases observed can be explained by the hypothesis of previously existed strong mutational AT pressure in the common predecessor of all archaea.
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Affiliation(s)
- Vladislav V Khrustalev
- Department of General Chemistry, Belarussian State Medical University, Minsk 220116, Belarus.
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Li S, Huang Q, Wang L, Lan Y, Zhang X, Yang B, Du P, Hua Z. A convenient spectrometric assay system for intracellular quantitative measurement of DNA glycosylase activity. Acta Biochim Biophys Sin (Shanghai) 2010; 42:381-7. [PMID: 20539937 DOI: 10.1093/abbs/gmq032] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Cytosine methylation is a vital biology event. However, it is also the source of genomic instability due to deamination of 5'-methylcytosine by spontaneous hydrolysis, which produces thymine and results in G:T mismatches. Thymine DNA glycosylase and methyl-CpG-binding protein 4 are major DNA glycosylases involved in the mismatch repair progress, and their activities have been measured in many related researches. In this study, we developed a convenient spectrometric assay system for specific and quantitative measurement of intracellular DNA glycosylase activity. A G:T mismatch was introduced into the upstream region of firefly luciferase-coding sequence in the pGL3-control plasmid. Only if the G:T mismatches were repaired to G:C, will luciferase be expressed in transfected cells. By measuring luciferase activity, which is simple and convenient, the intracellular DNA glycosylase activity can be determined.
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Affiliation(s)
- Shiying Li
- Jiangsu Center of Hepatobiliary Diseases and School of Stomatology, Affiliated Stomatological Hospital, Nanjing University, China
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Evans MD, Saparbaev M, Cooke MS. DNA repair and the origins of urinary oxidized 2'-deoxyribonucleosides. Mutagenesis 2010; 25:433-42. [PMID: 20522520 DOI: 10.1093/mutage/geq031] [Citation(s) in RCA: 74] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Monitoring oxidative stress in vivo is made easier by the ability to use samples obtained non-invasively, such as urine. The analysis of DNA oxidation, by measurement of oxidized 2'-deoxyribonucleosides in urine, particularly 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodG), has been reported extensively in the literature in many situations relating to various pathologies, populations and environmental exposures. Understanding the origins of urinary 8-oxodG, other than it simply being a marker of DNA oxidation or its synthetic precursors, is important to being able to effectively interpret differences in baseline urinary 8-oxodG levels between subject groups and changes in excretion. Diet and cell turnover play negligible roles in contributing to urinary 8-oxodG levels, leaving DNA repair as a primary source of this lesion. However, which repair processes contribute, and to what extent, to urinary 8-oxodG is still open to question. The most rational source would be the activity of selected members of the Nudix hydrolase family of enzymes, sanitizing the deoxyribonucleotide pool via the degradation of 8-oxo-7,8-dihydro-2'-deoxyguanosine-5'-triphosphate and 8-oxo-7,8-dihydro-2'-deoxyguanosine-5'-diphosphate, yielding mononucleotide products that can then be dephosphorylated to 8-oxodG and excreted. However, nucleotide excision repair (NER), transcription-coupled repair, nucleotide incision repair (NIR), mismatch repair and various exonuclease activities, such as proofreading function associated with DNA polymerases, can all feasibly generate initial products that could yield 8-oxodG after further metabolism. A recent study implying that a significant proportion of genomic 8-oxodG exists in the context of tandem lesions, refractory to repair by glycosylases, suggests the roles of NER and/or NIR remain to be further examined and defined as a source of 8-oxodG. 8-OxodG has been the primary focus of investigation, but other oxidized 2'-deoxyribonucleosides have been detected in urine, 2'-deoxythymidine glycol and 5-hydroxymethyl-2'-deoxyuridine; the origins of these compounds in urine, however, are presently even more speculative than for 8-oxodG.
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Affiliation(s)
- Mark D Evans
- Radiation and Oxidative Stress Section, Department of Cancer Studies and Molecular Medicine, University of Leicester, Leicester LE1 7RH, UK.
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Nitta M, Kozono D, Kennedy R, Stommel J, Ng K, Zinn PO, Kushwaha D, Kesari S, Furnari F, Hoadley KA, Chin L, DePinho RA, Cavenee WK, D'Andrea A, Chen CC. Targeting EGFR induced oxidative stress by PARP1 inhibition in glioblastoma therapy. PLoS One 2010; 5:e10767. [PMID: 20532243 PMCID: PMC2879424 DOI: 10.1371/journal.pone.0010767] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2010] [Accepted: 04/24/2010] [Indexed: 11/20/2022] Open
Abstract
Despite the critical role of Epidermal Growth Factor Receptor (EGFR) in glioblastoma pathogenesis [1], [2], EGFR targeted therapies have achieved limited clinical efficacy [3]. Here we propose an alternate therapeutic strategy based on the conceptual framework of non-oncogene addiction [4], [5]. A directed RNAi screen revealed that glioblastoma cells over-expressing EGFRvIII [6], an oncogenic variant of EGFR, become hyper-dependent on a variety of DNA repair genes. Among these, there was an enrichment of Base Excision Repair (BER) genes required for the repair of Reactive Oxygen Species (ROS)-induced DNA damage, including poly-ADP ribose polymerase 1 (PARP1). Subsequent studies revealed that EGFRvIII over-expression in glioblastoma cells caused increased levels of ROS, DNA strand break accumulation, and genome instability. In a panel of primary glioblastoma lines, sensitivity to PARP1 inhibition correlated with the levels of EGFR activation and oxidative stress. Gene expression analysis indicated that reduced expression of BER genes in glioblastomas with high EGFR expression correlated with improved patient survival. These observations suggest that oxidative stress secondary to EGFR hyper-activation necessitates increased cellular reliance on PARP1 mediated BER, and offer critical insights into clinical trial design.
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Affiliation(s)
- Masayuki Nitta
- Department of Radiation Oncology, Dana-Farber Cancer Institute, Boston, Massachusetts, United States of America
| | - David Kozono
- Department of Radiation Oncology, Dana-Farber Cancer Institute, Boston, Massachusetts, United States of America
- Harvard Radiation Oncology Program, Boston, Massachusetts, United States of America
| | - Richard Kennedy
- Almac Diagnostics, Craigavon, Northern Ireland, United Kingdom
| | - Jayne Stommel
- Department of Medical Oncology, Belfer Institute for Applied Cancer Science, Dana-Farber Cancer Institute, Boston, Massachusetts, United States of America
| | - Kimberly Ng
- Department of Radiation Oncology, Dana-Farber Cancer Institute, Boston, Massachusetts, United States of America
| | - Pascal O. Zinn
- Department of Radiation Oncology, Dana-Farber Cancer Institute, Boston, Massachusetts, United States of America
| | - Deepa Kushwaha
- Department of Radiation Oncology, Dana-Farber Cancer Institute, Boston, Massachusetts, United States of America
| | - Santosh Kesari
- Department of Neurology, Moores UCSD Cancer Center, University of California San Diego, La Jolla, California, United States of America
| | - Frank Furnari
- San Diego Branch, Ludwig Institute for Cancer Research, La Jolla, California, United States of America
| | - Katherine A. Hoadley
- Department of Genetics, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
| | - Lynda Chin
- Department of Medical Oncology, Belfer Institute for Applied Cancer Science, Dana-Farber Cancer Institute, Boston, Massachusetts, United States of America
| | - Ronald A. DePinho
- Department of Medical Oncology, Belfer Institute for Applied Cancer Science, Dana-Farber Cancer Institute, Boston, Massachusetts, United States of America
| | - Webster K. Cavenee
- San Diego Branch, Ludwig Institute for Cancer Research, La Jolla, California, United States of America
| | - Alan D'Andrea
- Department of Radiation Oncology, Dana-Farber Cancer Institute, Boston, Massachusetts, United States of America
| | - Clark C. Chen
- Department of Radiation Oncology, Dana-Farber Cancer Institute, Boston, Massachusetts, United States of America
- Division of Neurosurgery, Beth Israel Deaconess Medical Center, Boston, Massachusetts, United States of America
- * E-mail:
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Liu XP, Li CP, Hou JL, Liu YF, Liang RB, Liu JH. Expression and characterization of thymine-DNA glycosylase from Aeropyrum pernix. Protein Expr Purif 2010; 70:1-6. [DOI: 10.1016/j.pep.2009.10.006] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2009] [Revised: 10/04/2009] [Accepted: 10/06/2009] [Indexed: 10/20/2022]
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Wang ZG, Wu JX. [DNA methyltransferases: classification, functions and research progress]. YI CHUAN = HEREDITAS 2009; 31:903-12. [PMID: 19819843 DOI: 10.3724/sp.j.1005.2009.00903] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
DNA methylation is a postreplicative modification occurred in most prokaryotic and eukaryotic genomes, which has a variety of important biological functions including regulation of gene expression, gene imprinting, preservation of chromosomal integrity, and X-chromosome inactivation. According to their structure and functions, DNA methyltransferases (Dnmts) are divided into two major families in mammalian cells: maintenance methyltransferase (Dnmt1) and de novo methyltransferases (Dnmt3a, Dnmt3b, and Dnmt3L). In addition, Dnmt2 also displays weak DNA methyltransferase catalytic activity, but newly founded function is to methylate cytosine 38 in the anti-codon loop of tRNAAsp. These Dnmts are crucial for mammalian growth and development. Dnmts deficiency will lead to embryonic development defects, cancer, and other diseases. Therefore, Dnmts could be important therapeutical targets. This article summarizes the classification, function, and recent research progress in DNA methyltransferases.
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Affiliation(s)
- Zhi-Gang Wang
- Department of Biochemistry, Capital Institute of Pediatrics, Beijing, China.
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Besaratinia A, Pfeifer GP. DNA-lesion mapping in mammalian cells. Methods 2009; 48:35-9. [PMID: 19245834 DOI: 10.1016/j.ymeth.2009.02.008] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2008] [Accepted: 02/15/2009] [Indexed: 11/18/2022] Open
Abstract
Formation of DNA damage is a crucial event in carcinogenesis. Irreparable DNA lesions have the potential to cause mispairing during DNA replication, thereby giving rise to mutations. Critically important mutations in cancer-related genes, i.e., oncogenes and tumor suppressor genes, are key contributors to carcinogenesis. Theoretically, co-localization(s) of persistent DNA lesions and mutational hotspots in cancer-relevant genes can be used for causality inference. The inferred causality can be validated if a suspected carcinogen can similarly produce corresponding patterns of DNA damage and mutagenesis in vitro and/or in vivo. DNA-lesion footprinting (mapping) in conjunction with mutagenicity analysis is used for investigating cancer etiology. Ligation-mediated polymerase chain reaction (LM-PCR) is a versatile DNA-lesion footprinting technique, which enables sensitive and specific detection of DNA damage, at the level of nucleotide resolution, in genomic DNA. Here, we describe an updated protocol for LM-PCR analysis of the mammalian genome. This protocol can routinely be used for DNA-lesion footprinting of a variety of chemical and/or physical carcinogens in mammalian cells.
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Affiliation(s)
- Ahmad Besaratinia
- Division of Biology, Beckman Research Institute of the City of Hope National Medical Center, Duarte, CA 91010, USA.
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Baute J, Depicker A. Base excision repair and its role in maintaining genome stability. Crit Rev Biochem Mol Biol 2008; 43:239-76. [PMID: 18756381 DOI: 10.1080/10409230802309905] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
For all living organisms, genome stability is important, but is also under constant threat because various environmental and endogenous damaging agents can modify the structural properties of DNA bases. As a defense, organisms have developed different DNA repair pathways. Base excision repair (BER) is the predominant pathway for coping with a broad range of small lesions resulting from oxidation, alkylation, and deamination, which modify individual bases without large effect on the double helix structure. As, in mammalian cells, this damage is estimated to account daily for 10(4) events per cell, the need for BER pathways is unquestionable. The damage-specific removal is carried out by a considerable group of enzymes, designated as DNA glycosylases. Each DNA glycosylase has its unique specificity and many of them are ubiquitous in microorganisms, mammals, and plants. Here, we review the importance of the BER pathway and we focus on the different roles of DNA glycosylases in various organisms.
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Affiliation(s)
- Joke Baute
- Department of Plant Systems Biology, Flanders Institute for Biotechnology, Gent, Belgium
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Djuric Z, Bird CE, Furumoto-Dawson A, Rauscher GH, Ruffin MT, Stowe RP, Tucker KL, Masi CM. Biomarkers of Psychological Stress in Health Disparities Research. ACTA ACUST UNITED AC 2008; 1:7-19. [PMID: 20305736 DOI: 10.2174/1875318300801010007] [Citation(s) in RCA: 81] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Psychological stress can contribute to health disparities in populations that are confronted with the recurring stress of everyday life. A number of biomarkers have been shown to be affected by psychological stress. These biomarkers include allostatic load, which is a summary measure of the cumulative biological burden of the repeated attempts to adapt to daily stress. Allostatic load includes effects on the hypothalamic-pituitary axis, the sympathetic nervous system and the cardiovascular system. These in turn affect the immune system via bidirectional signaling pathways. Evidence is also building that psychological stress, perhaps via heightened inflammatory states, can increase oxidative stress levels and DNA damage. The inter-relationships of ethnicity, genotype, gene expression and ability to adequately mitigate stress response are just starting to be appreciated. The need to conduct these studies in disadvantaged populations is clear and requires methods to address potential logistical barriers. Biomarkers can help characterize and quantify the biological impact of psychological stress on the etiology of health disparities.
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Xu G, Herzig M, Rotrekl V, Walter CA. Base excision repair, aging and health span. Mech Ageing Dev 2008; 129:366-82. [PMID: 18423806 PMCID: PMC2526234 DOI: 10.1016/j.mad.2008.03.001] [Citation(s) in RCA: 85] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2007] [Revised: 02/28/2008] [Accepted: 03/05/2008] [Indexed: 12/18/2022]
Abstract
DNA damage and mutagenesis are suggested to contribute to aging through their ability to mediate cellular dysfunction. The base excision repair (BER) pathway ameliorates a large number of DNA lesions that arise spontaneously. Many of these lesions are reported to increase with age. Oxidized guanine, repaired largely via base excision repair, is particularly well studied and shown to increase with age. Spontaneous mutant frequencies also increase with age which suggests that mutagenesis may contribute to aging. It is widely accepted that genetic instability contributes to age-related occurrences of cancer and potentially other age-related pathologies. BER activity decreases with age in multiple tissues. The specific BER protein that appears to limit activity varies among tissues. DNA polymerase-beta is reduced in brain from aged mice and rats while AP endonuclease is reduced in spermatogenic cells obtained from old mice. The differences in proteins that appear to limit BER activity among tissues may represent true tissue-specific differences in activity or may be due to differences in techniques, environmental conditions or other unidentified differences among the experimental approaches. Much remains to be addressed concerning the potential role of BER in aging and age-related health span.
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Affiliation(s)
- Guogang Xu
- Department of Cellular & Structural Biology, The University of Texas Health Science Center at San Antonio, 7703 Floyd Curl Drive, San Antonio, TX 78229-3900
| | - Maryanne Herzig
- Department of Cellular & Structural Biology, The University of Texas Health Science Center at San Antonio, 7703 Floyd Curl Drive, San Antonio, TX 78229-3900
| | - Vladimir Rotrekl
- Institute of Experimental Medicine, Department of Molecular Embryology, Masaryk University, Faculty of Medicine, Department of Biology, Kamenice 5, Building A6, 62500 Brno, Czech Republic
| | - Christi A. Walter
- Department of Cellular & Structural Biology, The University of Texas Health Science Center at San Antonio, 7703 Floyd Curl Drive, San Antonio, TX 78229-3900
- South Texas Veteran’s Health Care System, 7400 Merton Minter Blvd, San Antonio, TX 78229
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