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TDG Gene Polymorphisms and Their Possible Association with Colorectal Cancer: A Case Control Study. JOURNAL OF ONCOLOGY 2019; 2019:7091815. [PMID: 31239841 PMCID: PMC6556271 DOI: 10.1155/2019/7091815] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/27/2019] [Revised: 04/05/2019] [Accepted: 05/07/2019] [Indexed: 12/28/2022]
Abstract
Genetic alterations that might lead to colorectal cancer involve essential genes including those involved in DNA repair, inclusive of base excision repair (BER). Thymine DNA glycosylase (TDG) is one of the most well characterized BER genes that catalyzes the removal of thymine moieties from G/T mismatches and is also involved in many cellular functions, such as the regulation of gene expression, transcriptional coactivation, and the control of epigenetic DNA modification. Mutation of the TDG gene is implicated in carcinogenesis. In the present study, we aimed to investigate the association between TDG gene polymorphisms and their involvement in colon cancer susceptibility. One hundred blood samples were obtained from colorectal cancer patients and healthy controls for the genotyping of seven SNPs in the TDG gene. DNA was extracted from the blood, and the polymorphic sites (SNPs) rs4135113, rs4135050, rs4135066, rs3751209, rs1866074, and rs1882018 were investigated using TaqMan genotyping. One of the six TDG SNPs was associated with an increased risk of colon cancer. The AA genotype of the TDG SNP rs4135113 increased the risk of colon cancer development by more than 3.6-fold, whereas the minor allele A increased the risk by 1.6-fold. It also showed a 5-fold higher risk in patients over the age of 57. SNP rs1866074 showed a significant protective association in CRC patients. The GA genotype of TDG rs3751209 was associated with a decreased risk in males. There is a significant relationship between TDG gene function and colorectal cancer progression.
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Chang JTH, Wang F, Chapin W, Huang RS. Identification of MicroRNAs as Breast Cancer Prognosis Markers through the Cancer Genome Atlas. PLoS One 2016; 11:e0168284. [PMID: 27959953 PMCID: PMC5154569 DOI: 10.1371/journal.pone.0168284] [Citation(s) in RCA: 73] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2016] [Accepted: 11/29/2016] [Indexed: 12/21/2022] Open
Abstract
Breast cancer is the second-most common cancer and second-leading cause of cancer mortality in American women. The dysregulation of microRNAs (miRNAs) plays a key role in almost all cancers, including breast cancer. We comprehensively analyzed miRNA expression, global gene expression, and patient survival from the Cancer Genomes Atlas (TCGA) to identify clinically relevant miRNAs and their potential gene targets in breast tumors. In our analysis, we found that increased expression of 12 mature miRNAs-hsa-miR-320a, hsa-miR-361-5p, hsa-miR-103a-3p, hsa-miR-21-5p, hsa-miR-374b-5p, hsa-miR-140-3p, hsa-miR-25-3p, hsa-miR-651-5p, hsa-miR-200c-3p, hsa-miR-30a-5p, hsa-miR-30c-5p, and hsa-let-7i-5p -each predicted improved breast cancer survival. Of the 12 miRNAs, miR-320a, miR-361-5p, miR-21-5p, miR-103a-3p were selected for further analysis. By correlating global gene expression with miRNA expression and then employing miRNA target prediction analysis, we suggest that the four miRNAs may exert protective phenotypes by targeting breast oncogenes that contribute to patient survival. We propose that miR-320a targets the survival-associated genes RAD51, RRP1B, and TDG; miR-361-5p targets ARCN1; and miR-21-5p targets MSH2, RMND5A, STAG2, and UBE2D3. The results of our stringent bioinformatics approach for identifying clinically relevant miRNAs and their targets indicate that miR-320a, miR-361-5p, and miR-21-5p may contribute to breast cancer survival.
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Affiliation(s)
- Jeremy T-H. Chang
- Biological Sciences Collegiate Division, University of Chicago, Chicago, Illinois, United States of America
| | - Fan Wang
- Department of Medicine, University of Chicago, Chicago, Illinois, United States of America
| | - William Chapin
- Pritzker School of Medicine, University of Chicago, Chicago, Illinois, United States of America
| | - R. Stephanie Huang
- Department of Medicine, University of Chicago, Chicago, Illinois, United States of America
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3
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Sun J, Shen Q, Lu H, Jiang Z, Xu W, Feng L, Li L, Wang X, Cai X, Jin H. Oncogenic Ras suppresses ING4-TDG-Fas axis to promote apoptosis resistance. Oncotarget 2016; 6:41997-2007. [PMID: 26544625 PMCID: PMC4747204 DOI: 10.18632/oncotarget.6015] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2015] [Accepted: 10/12/2015] [Indexed: 02/07/2023] Open
Abstract
Ras is aberrantly activated in many cancers and active DNA demethylation plays a fundamental role to establish DNA methylation pattern which is of importance to cancer development. However, it was unknown whether and how Ras regulate DNA demethylation during carcinogenesis. Here we found that Ras downregulated thymine-DNA glycosylase (TDG), a DNA demethylation enzyme, by inhibiting the interaction of transcription activator ING4 with TDG promoter. TDG recruited histone lysine demethylase JMJD3 to the Fas promoter and activated its expression, thus restoring sensitivity to apoptosis. TDG suppressed in vivo tumorigenicity of xenograft pancreatic cancer. Thus, we speculate that reversing Ras-mediated ING4 inhibition to activate Fas expression is a potential therapeutic approach for Ras-driven cancers.
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Affiliation(s)
- Jie Sun
- Laboratory of Cancer Biology, Provincial Key Lab of Biotherapy in Zhejiang, Sir Runrun Shaw Hospital, Medical School of Zhejiang University, Hangzhou, China
| | - Qi Shen
- Department of Medical Oncology, Sir Runrun Shaw Hospital, Medical School of Zhejiang University, Hangzhou, China
| | - Haiqi Lu
- Department of Medical Oncology, Sir Runrun Shaw Hospital, Medical School of Zhejiang University, Hangzhou, China
| | - Zhinong Jiang
- Department of Pathology, Sir Runrun Shaw Hospital, Medical School of Zhejiang University, Hangzhou, China
| | - Wenxia Xu
- Laboratory of Cancer Biology, Provincial Key Lab of Biotherapy in Zhejiang, Sir Runrun Shaw Hospital, Medical School of Zhejiang University, Hangzhou, China
| | - Lifeng Feng
- Laboratory of Cancer Biology, Provincial Key Lab of Biotherapy in Zhejiang, Sir Runrun Shaw Hospital, Medical School of Zhejiang University, Hangzhou, China
| | - Ling Li
- Division of Hematopoietic Stem Cell and Leukemia Research, City of Hope National Medical Center, Duarte, CA, USA
| | - Xian Wang
- Department of Medical Oncology, Sir Runrun Shaw Hospital, Medical School of Zhejiang University, Hangzhou, China
| | - Xiujun Cai
- Department of General Surgery, Sir Runrun Shaw Hospital, Medical School of Zhejiang University, Hangzhou, China
| | - Hongchuan Jin
- Laboratory of Cancer Biology, Provincial Key Lab of Biotherapy in Zhejiang, Sir Runrun Shaw Hospital, Medical School of Zhejiang University, Hangzhou, China
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4
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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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5
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Fortes FP, Kuasne H, Marchi FA, Miranda PM, Rogatto SR, Achatz MI. DNA methylation patterns of candidate genes regulated by thymine DNA glycosylase in patients with TP53 germline mutations. ACTA ACUST UNITED AC 2015; 48:610-5. [PMID: 25945745 PMCID: PMC4512099 DOI: 10.1590/1414-431x20154026] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2014] [Accepted: 02/05/2015] [Indexed: 01/07/2023]
Abstract
Li-Fraumeni syndrome (LFS) is a rare, autosomal dominant, hereditary cancer predisposition disorder. In Brazil, the p.R337H TP53 founder mutation causes the variant form of LFS, Li-Fraumeni-like syndrome. The occurrence of cancer and age of disease onset are known to vary, even in patients carrying the same mutation, and several mechanisms such as genetic and epigenetic alterations may be involved in this variability. However, the extent of involvement of such events has not been clarified. It is well established that p53 regulates several pathways, including the thymine DNA glycosylase (TDG) pathway, which regulates the DNA methylation of several genes. This study aimed to identify the DNA methylation pattern of genes potentially related to the TDG pathway (CDKN2A, FOXA1, HOXD8, OCT4, SOX2, and SOX17) in 30 patients with germline TP53 mutations, 10 patients with wild-type TP53, and 10 healthy individuals. We also evaluated TDG expression in patients with adrenocortical tumors (ADR) with and without the p.R337H TP53 mutation. Gene methylation patterns of peripheral blood DNA samples assessed by pyrosequencing revealed no significant differences between the three groups. However, increased TDG expression was observed by quantitative reverse transcription PCR in p.R337H carriers with ADR. Considering the rarity of this phenotype and the relevance of these findings, further studies using a larger sample set are necessary to confirm our results.
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Affiliation(s)
- F P Fortes
- CIPE, Laboratrio de Oncogentica Molecular, A.C. Camargo Cancer Center, São Paulo, SP, Brasil
| | - H Kuasne
- CIPE, Laboratrio NeoGene, A.C. Camargo Cancer Center, São Paulo, SP, Brasil
| | - F A Marchi
- CIPE, Laboratrio NeoGene, A.C. Camargo Cancer Center, São Paulo, SP, Brasil
| | - P M Miranda
- CIPE, Laboratrio NeoGene, A.C. Camargo Cancer Center, São Paulo, SP, Brasil
| | - S R Rogatto
- CIPE, Laboratrio NeoGene, A.C. Camargo Cancer Center, São Paulo, SP, Brasil
| | - M I Achatz
- CIPE, Laboratrio de Oncogentica Molecular, A.C. Camargo Cancer Center, São Paulo, SP, Brasil
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6
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Abstract
DNA methylation has long been considered a very stable DNA modification in mammals that could only be removed by replication in the absence of remethylation - that is, by mere dilution of this epigenetic mark (so-called passive DNA demethylation). However, in recent years, a significant number of studies have revealed the existence of active processes of DNA demethylation in mammals, with important roles in development and transcriptional regulation, allowing the molecular mechanisms of active DNA demethylation to be unraveled. In this article, we review the recent literature highlighting the prominent role played in active DNA demethylation by base excision repair and especially by TDG.
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Affiliation(s)
- Shannon R Dalton
- Cancer Biology Program, Epigenetics & Progenitor Cells Program, Fox Chase Cancer Center, PA 19111, USA
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Abstract
The base excision repair system is vital to the repair of endogenous and exogenous DNA damage. This pathway is initiated by one of several DNA glycosylases that recognizes and excises specific DNA lesions in a coordinated fashion. Methyl-CpG Domain Protein 4 (MBD4) and Thymine DNA Glycosylase (TDG) are the two major G:T glycosylases that remove thymine generated by the deamination of 5-methylcytosine. Both of these glycosylases also remove a variety of other base lesions, including G:U and preferentially act at CpG sites throughout the genome. Many have questioned the purpose of seemingly redundant glycosylases, but new information has emerged to suggest MBD4 and TDG have diverse biological functions. MBD4 has been closely linked to apoptosis, while TDG has been clearly implicated in transcriptional regulation. This article reviews all of these developments, and discusses the consequences of germline and somatic mutations that lead to non-synonymous amino acid substitutions on MBD4 and TDG protein function. In addition, we report the finding of alternatively spliced variants of MBD4 and TDG and the results of functional studies of a tumor-associated variant of MBD4.
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Poetsch M, Zimmermann A, Wolf E, Kleist B. Loss of heterozygosity occurs predominantly, but not exclusively, in the epithelial compartment of pleomorphic adenoma. Neoplasia 2005; 7:688-95. [PMID: 16026648 PMCID: PMC1501429 DOI: 10.1593/neo.05163] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2005] [Revised: 03/22/2005] [Accepted: 03/22/2005] [Indexed: 11/18/2022] Open
Abstract
Pleomorphic adenoma (PA), being the most common benign tumor of the salivary glands, is composed of epithelial and mesenchymal compartments. In this study, we analyzed 19 microsatellite markers from chromosomal arms 6q, 8q, 9p, 12q, and 17p in 31 PAs and 3 carcinoma ex pleomorphic adenomas (CXPAs) as well as 11 other non-PA-related carcinomas of the salivary gland for comparison. In our analysis, we differentiated between epithelial and mesenchymal tissues. Loss of heterozygosity (LOH) in PAs was most often found in 8q (32%) and 12q (29%). Two of the three CXPAs displayed allelic loss at all chromosomal arms investigated, whereas the results of the non-PA-related carcinomas were rather heterogeneous. LOH could not only be detected in the epithelial, but also in the mesenchymal, compartments of a subset of PAs, especially at chromosomal arm 8q. Concerning the CXPAs, we were able to demonstrate allelic losses not only in the malignant epithelial compartment, but also in the residual adenoma parts. Our data give further evidence that alterations in 8q may be an early event in PA tumorigenesis, whereas LOH in 12q may characterize cells with the potential to transform in CXPAs.
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Affiliation(s)
- Micaela Poetsch
- Institute of Forensic Medicine, University of Greifswald, Greifswald, Germany.
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Krześniak M, Butkiewicz D, Samojedny A, Chorazy M, Rusin M. Polymorphisms in TDG and MGMT genes - epidemiological and functional study in lung cancer patients from Poland. Ann Hum Genet 2005; 68:300-12. [PMID: 15225156 DOI: 10.1046/j.1529-8817.2004.00079.x] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Functional genetic polymorphisms of DNA repair genes are good candidates for cancer susceptibility markers. We studied two genes coding for proteins removing small DNA adducts by direct repair (MGMT), or mispaired DNA bases by base excision repair (TDG). The non-silent polymorphisms of MGMT (84:Phe, 143:Val, 178:Arg) and TDG (199:Ser, 367:Met), and the functional MGMT enhancer polymorphism, did not show any statistically significant association with lung cancer risk in our case-control analysis, but due to the relatively small number of individuals, strong conclusions on cancer risk association or lack thereof cannot be made. Sequencing of the TDG cDNA has not revealed any novel polymorphism, but did find an alternatively spliced mRNA missing exon 2. Our search for polymorphisms within the promoter-enhancer region of MGMT revealed three novel sequence variants. The functional significance of the previously published MGMT enhancer polymorphism (1099C->T) was assessed. The less frequent sequence variant of the enhancer was associated with a modest (16-64%), but statistically significant, increase of MGMT promoter-enhancer activity in the studied cell lines. This work points to the importance of studying the expression-regulating elements of genes, as they may contain functional polymorphisms with the potential for modulating risk of various diseases, including cancer.
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Affiliation(s)
- M Krześniak
- Department of Tumor Biology, Center of Oncology, Maria Skłodowska-Curie Memorial Institute, 44-101 Gliwice, Poland
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Schneider BG, Rha SY, Chung HC, Bravo JC, Mera R, Torres JC, Plaisance KT, Schlegel R, McBride CM, Reveles XT, Leach RJ. Regions of allelic imbalance in the distal portion of chromosome 12q in gastric cancer. Mol Pathol 2003; 56:141-9. [PMID: 12782760 PMCID: PMC1187309 DOI: 10.1136/mp.56.3.141] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/12/2003] [Indexed: 11/04/2022]
Abstract
AIMS To define regions of loss on the distal portion of chromosome 12q in gastric adenocarcinoma. METHODS Microsatellite analysis on chromosome 12 was performed on 19 human gastric cancer cell lines using 77 markers, 71 of which were within or distal to 12q21; some portions of this region showed extended regions of homozygosity (ERHs) in 10 of 19 gastric cancer cell lines. In addition, microdissected tumour cells from 76 primary gastric adenocarcinomas were examined using 13 markers of interest implicated by the cell line data; 70% of these showed allelic imbalance (AI) at one or more markers in or distal to 12q21. RESULTS Mapping ERHs in the cell lines and sites of AI in the tumours identified three regions that contain putative tumour suppressor genes: region A is located within 2.8 Mb between markers D12S1667 and D12S88; region B, within 1.9 Mb between markers D12S1607 and D12S78; and region C, in 0.74 Mb between markers D12S342 and D12S324. Fluorescence in situ hybridisation (FISH) analysis in two cell lines confirmed that two of the ERHs reflected deletions, not amplifications, of D12S81 in region A and D12S340 in region C. FISH analysis of marker D12S1075 within an ERH containing region B in one cell line showed neither amplification nor deletion. AI on 12q was not associated with prognosis, but was associated with ethnicity of the patient. CONCLUSIONS These results identify regions on chromosome 12 that appear to contain tumour suppressor genes important in the development of gastric cancer.
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Affiliation(s)
- B G Schneider
- Louisiana State University Health Sciences Center, Department of Pathology and Stanley Scott Cancer Center, New Orleans, LA 70112, USA.
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Reis RM, Herva R, Brandner S, Koivukangas J, Mironov N, Bär W, Kleihues P, Ohgaki H. Second primary glioblastoma. J Neuropathol Exp Neurol 2001; 60:208-15. [PMID: 11273008 DOI: 10.1093/jnen/60.2.208] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Although characterized by a highly variable phenotype and multiple genetic alterations, glioblastomas are considered monoclonal in origin. We here report on a 64-yr-old patient who developed a second glioblastoma in the left frontal lobe 10 yr after surgical resection of a glioblastoma of right frontal lobe. The first tumor contained 2 p53 mutations, in codon 213 (CGA-->TGA, Arg-->stop) and codon 306 (CGA-->TGA, Arg-->stop), further, 1 missense PTEN mutation (codon 257, TTC-->TTA, Phe-->Leu) and a silent PTEN mutation (codon 154, TTC-->TTT, Phe-->Phe). The second glioblastoma also contained multiple, but different mutations: p53 mutations in codons 158 (CGC-->CAC, Arg-->His) and 273 (CGT-->TGT, Arg-->Cys), and a PTEN mutation in codon 233 (CGA-->TGA, Arg-->Stop). Both neoplasms had a homozygous p16 deletion. The discordant pattern of mutations indicates that the second glioblastoma was not a recurrence but an independent second glioblastoma. The presence in these neoplasms of multiple mutations in tumor suppressor genes suggests the involvement of a novel disease mechanism but there was no indication of a DNA mismatch repair deficiency or of an inherited tumor syndrome.
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Affiliation(s)
- R M Reis
- International Agency for Research on Cancer, Lyon, France
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Yatsuoka T, Sunamura M, Furukawa T, Fukushige S, Yokoyama T, Inoue H, Shibuya K, Takeda K, Matsuno S, Horii A. Association of poor prognosis with loss of 12q, 17p, and 18q, and concordant loss of 6q/17p and 12q/18q in human pancreatic ductal adenocarcinoma. Am J Gastroenterol 2000; 95:2080-5. [PMID: 10950061 DOI: 10.1111/j.1572-0241.2000.02171.x] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
OBJECTIVE Pancreatic cancer is one of the diseases with the poorest prognosis, but the associated genetic alterations are not yet well understood. The genetic alterations reported to date in pancreatic cancer include frequent mutations of the KRAS, TP53, p16, and SMAD4 genes. Mutation of the TP53 gene was reported to be associated with a poor prognosis. In this study, we analyzed the association of loss of heterozygosity (LOH) with clinicopathological features to attempt to devise effective methods in the future for clinically applying our results to diagnosis and treatment. METHODS A total of 55 tumors from patients with primary pancreatic ductal carcinomas (34 men and 21 women, mean average age 63.9 yr) in which all the relevant clinical and pathological data were available were analyzed. A total of 46 cases were surgically resected, and nine cases were not. Tumor cells as well as corresponding normal cells were collected by microdissection under a microscope, and DNAs were purified. Allelotype analysis was performed by the PCR-based method, and the results were statistically analyzed. RESULTS LOH of > or =30% were observed on chromosome arms 17p (47%, 17/36), 9p (45%, 14/31), 18q (43%, 15/35), 12q (34%, 10/29), and 6q (30%, 10/33). LOH of 12q, 17p, and 18q were significantly associated with a poor prognosis. Concordant losses of 6q with 17p and 18q were significantly associated with a poor prognosis. Concordant losses of 6q with 17p and of 12q with 18q were also found. CONCLUSIONS Because LOH of 12q, 17p, and 18q are significantly associated with a poor prognosis, mutation of the putative tumor suppressor genes on these chromosome arms may play significant roles in the disease progression. Concordant losses of 6q with 17p and of 12q with 18q suggest that protein products of putative tumor suppressor genes on 6q and 12q may function in association with TP53 and SMAD4, respectively.
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Affiliation(s)
- T Yatsuoka
- Department of Molecular Pathology, Tohoku University School of Medicine, Sendai, Miyagi, Japan
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Abstract
About 23% of mutations in hereditary human diseases and 24% of mutations in p53 in human cancers are G to A transitions at sites of cytosine methylation suggesting that these sites are either foci for DNA damage, or foci for damage that is poorly repaired. Thymine produced at these sites by the hydrolytic deamination of 5-methylcytosine is removed by thymine-DNA glycosylase. Thymine-DNA glycosylase will also remove 3,N(4)-ethenocytosine and uracil from DNA. The action of this enzyme is limited by its very low k(cat) and by tight binding to the apurinic site produced when the thymine is removed. These properties of the enzyme suggest that the inefficiency of the base excision repair pathway that it initiates may be the underlying cause of the prevalence of these mutations.
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Affiliation(s)
- T R Waters
- Department of Biochemistry and Molecular Biology, University College London, London, UK.
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