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1.
Nucleic Acids Res ; 48(4): 2173-2188, 2020 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-31925419

RESUMO

The XPA protein functions together with the single-stranded DNA (ssDNA) binding protein RPA as the central scaffold to ensure proper positioning of repair factors in multi-protein nucleotide excision repair (NER) machinery. We previously determined the structure of a short motif in the disordered XPA N-terminus bound to the RPA32C domain. However, a second contact between the XPA DNA-binding domain (XPA DBD) and the RPA70AB tandem ssDNA-binding domains, which is likely to influence the orientation of XPA and RPA on the damaged DNA substrate, remains poorly characterized. NMR was used to map the binding interfaces of XPA DBD and RPA70AB. Combining NMR and X-ray scattering data with comprehensive docking and refinement revealed how XPA DBD and RPA70AB orient on model NER DNA substrates. The structural model enabled design of XPA mutations that inhibit the interaction with RPA70AB. These mutations decreased activity in cell-based NER assays, demonstrating the functional importance of XPA DBD-RPA70AB interaction. Our results inform ongoing controversy about where XPA is bound within the NER bubble, provide structural insights into the molecular basis for malfunction of disease-associated XPA missense mutations, and contribute to understanding of the structure and mechanical action of the NER machinery.


Assuntos
Reparo do DNA/genética , Modelos Moleculares , Proteína de Replicação A/química , Proteína de Xeroderma Pigmentoso Grupo A/química , DNA/química , DNA/genética , Dano ao DNA/genética , DNA de Cadeia Simples/química , DNA de Cadeia Simples/genética , Proteínas de Ligação a DNA/química , Proteínas de Ligação a DNA/genética , Humanos , Espectroscopia de Ressonância Magnética , Ligação Proteica/genética , Proteína de Replicação A/genética , Proteína de Xeroderma Pigmentoso Grupo A/genética
2.
BMC Cancer ; 20(1): 17, 2020 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-31906898

RESUMO

BACKGROUND: Germ cell tumours (GCTs) represent a highly curable malignity as they respond well to cisplatin (CDDP)-based chemotherapy. Nevertheless, a small proportion of GCT patients relapse or do not respond to therapy. As this might be caused by an increased capacity to repair CDDP-induced DNA damage, identification of DNA repair biomarkers predicting inadequate or aberrant response to CDDP, and thus poor prognosis for GCT patients, poses a challenge. The objective of this study is to examine the expression levels of the key nucleotide excision repair (NER) factors, XPA, ERCC1 and XPF, in GCT patients and cell lines. METHODS: Two hundred seven GCT patients' specimens with sufficient follow-up clinical-pathological data and pairwise combinations of CDDP-resistant and -sensitive GCT cell lines were included. Immunohistochemistry was used to detect the ERCC1, XPF and XPA protein expression levels in GCT patients' specimen and Western blot and qRT-PCR examined the protein and mRNA expression levels in GCT cell lines. RESULTS: GCT patients with low XPA expression had significantly better overall survival than patients with high expression (hazard ratio = 0.38, 95% confidence interval: 0.12-1.23, p = 0.0228). In addition, XPA expression was increased in the non-seminomatous histological subtype, IGCCCG poor prognosis group, increasing S stage, as well as the presence of lung, liver and non-pulmonary visceral metastases. Importantly, a correlation between inadequate or aberrant CDDP response and XPA expression found in GCT patients was also seen in GCT cell lines. CONCLUSIONS: XPA expression is an additional independent prognostic biomarker for stratifying GCT patients, allowing for improvements in decision-making on treatment for those at high risk of refractoriness or relapse. In addition, it could represent a novel therapeutic target in GCTs.


Assuntos
Antineoplásicos/farmacologia , Cisplatino/farmacologia , Reparo do DNA/genética , Neoplasias Embrionárias de Células Germinativas/metabolismo , Neoplasias Testiculares/metabolismo , Proteína de Xeroderma Pigmentoso Grupo A/metabolismo , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Linhagem Celular Tumoral , Dano ao DNA/efeitos dos fármacos , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Resistencia a Medicamentos Antineoplásicos , Endonucleases/genética , Endonucleases/metabolismo , Humanos , Imuno-Histoquímica , Masculino , Recidiva Local de Neoplasia/genética , Recidiva Local de Neoplasia/metabolismo , Neoplasias Embrionárias de Células Germinativas/tratamento farmacológico , Neoplasias Embrionárias de Células Germinativas/genética , Neoplasias Embrionárias de Células Germinativas/patologia , Fosforilação , Prognóstico , Neoplasias Testiculares/tratamento farmacológico , Neoplasias Testiculares/genética , Neoplasias Testiculares/patologia , Proteína de Xeroderma Pigmentoso Grupo A/genética
3.
DNA Repair (Amst) ; 80: 52-58, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31279170

RESUMO

Xeroderma pigmentosum (XP) is a genetic disorder associated with defects in nucleotide excision repair, a pathway that eliminates a wide variety of helix-distorting DNA lesions, including ultraviolet-induced pyrimidine dimers. In addition to skin diseases in sun-exposed areas, approximately 25% of XP patients develop progressive neurological disease, which has been hypothesized to be associated with the accumulation of an oxidatively generated type of DNA damage called purine 8,5'-cyclo-2'-deoxynucleoside (cyclopurine). However, that hypothesis has not been verified. In this study, we tested that hypothesis by using the XP group A gene-knockout (Xpa-/-) mouse model. To quantify cyclopurine lesions in this model, we previously established an enzyme-linked immunosorbent assay (ELISA) using a monoclonal antibody (CdA-1) that specifically recognizes 8,5'-cyclo-2'-deoxyadenosine (cyclo-dA). By optimizing conditions, we increased the ELISA sensitivity to a detection limit of ˜one cyclo-dA lesion/106 nucleosides. The improved ELISA revealed that cyclo-dA lesions accumulate with age in the brain tissues of Xpa-/- and of wild-type (wt) mice, but there were significantly more cyclo-dA lesions in Xpa-/- mice than in wt mice at 6, 24 and 29 months of age. These findings are consistent with the long-standing hypothesis that the age-dependent accumulation of endogenous cyclopurine lesions in the brain may be critical for XP neurological abnormalities.


Assuntos
Encéfalo/metabolismo , Dano ao DNA , Desoxiadenosinas/análise , Proteína de Xeroderma Pigmentoso Grupo A/genética , Xeroderma Pigmentoso/genética , Fatores Etários , Animais , DNA/química , DNA/metabolismo , Reparo do DNA , Modelos Animais de Doenças , Camundongos , Camundongos Knockout , Testes de Mutagenicidade
4.
Nat Commun ; 10(1): 2885, 2019 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-31253769

RESUMO

Nucleotide excision repair (NER) is the major DNA repair pathway that removes UV-induced and bulky DNA lesions. There is currently no structure of NER intermediates, which form around the large multisubunit transcription factor IIH (TFIIH). Here we report the cryo-EM structure of an NER intermediate containing TFIIH and the NER factor XPA. Compared to its transcription conformation, the TFIIH structure is rearranged such that its ATPase subunits XPB and XPD bind double- and single-stranded DNA, consistent with their translocase and helicase activities, respectively. XPA releases the inhibitory kinase module of TFIIH, displaces a 'plug' element from the DNA-binding pore in XPD, and together with the NER factor XPG stimulates XPD activity. Our results explain how TFIIH is switched from a transcription to a repair factor, and provide the basis for a mechanistic analysis of the NER pathway.


Assuntos
Reparo do DNA , Fator de Transcrição TFIIH/metabolismo , Adenosina Trifosfatases , Animais , Linhagem Celular , Clonagem Molecular , Microscopia Crioeletrônica , DNA/química , DNA Helicases/genética , DNA Helicases/metabolismo , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Endonucleases/genética , Endonucleases/metabolismo , Escherichia coli , Regulação da Expressão Gênica , Humanos , Insetos , Modelos Químicos , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Proteínas Recombinantes , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Proteína de Xeroderma Pigmentoso Grupo A/genética , Proteína de Xeroderma Pigmentoso Grupo A/metabolismo , Proteína Grupo D do Xeroderma Pigmentoso/genética , Proteína Grupo D do Xeroderma Pigmentoso/metabolismo
5.
Nucleic Acids Res ; 47(16): 8537-8547, 2019 09 19.
Artigo em Inglês | MEDLINE | ID: mdl-31226203

RESUMO

Apurinic/apyrimidinic (AP) sites are a class of highly mutagenic and toxic DNA lesions arising in the genome from a number of exogenous and endogenous sources. Repair of AP lesions takes place predominantly by the base excision pathway (BER). However, among chemically heterogeneous AP lesions formed in DNA, some are resistant to the endonuclease APE1 and thus refractory to BER. Here, we employed two types of reporter constructs accommodating synthetic APE1-resistant AP lesions to investigate the auxiliary repair mechanisms in human cells. By combined analyses of recovery of the transcription rate and suppression of transcriptional mutagenesis at specifically positioned AP lesions, we demonstrate that nucleotide excision repair pathway (NER) efficiently removes BER-resistant AP lesions and significantly enhances the repair of APE1-sensitive ones. Our results further indicate that core NER components XPA and XPF are equally required and that both global genome (GG-NER) and transcription coupled (TC-NER) subpathways contribute to the repair.


Assuntos
Reparo do DNA , DNA Liase (Sítios Apurínicos ou Apirimidínicos)/genética , Proteínas de Ligação a DNA/genética , DNA/genética , Proteína de Xeroderma Pigmentoso Grupo A/genética , Sequência de Bases , Proteína 9 Associada à CRISPR/genética , Proteína 9 Associada à CRISPR/metabolismo , Sistemas CRISPR-Cas , Linhagem Celular Transformada , DNA/química , DNA/metabolismo , Dano ao DNA , DNA Liase (Sítios Apurínicos ou Apirimidínicos)/metabolismo , Proteínas de Ligação a DNA/deficiência , Fibroblastos/citologia , Fibroblastos/metabolismo , Edição de Genes/métodos , Técnicas de Inativação de Genes , Genoma Humano , Humanos , Mutação , Ligação Proteica , Pele/citologia , Pele/metabolismo , Transcrição Genética , Proteína de Xeroderma Pigmentoso Grupo A/metabolismo
6.
Methods Mol Biol ; 1999: 217-221, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31127579

RESUMO

With the recent interest in targeting the DNA damage response (DDR) and DNA repair, new screening methodologies are needed to broaden the scope of targetable proteins beyond kinases and traditional enzymes. Many of the proteins involved in the DDR and repair impart their activity by making specific contacts with DNA. These protein-nucleic acid interactions represent a tractable target for perturbation with small molecules. We describe a high throughput, solution-based equilibrium binding fluorescence polarization assay that can be applied to a wide array of protein-nucleic acid interactions. The assay is sensitive, stable, and able to identify small molecules capable of blocking DNA-protein interactions.


Assuntos
Reparo do DNA/efeitos dos fármacos , Ensaios de Triagem em Larga Escala/métodos , Proteína de Replicação A/antagonistas & inibidores , Proteína de Xeroderma Pigmentoso Grupo A/antagonistas & inibidores , DNA/genética , DNA/metabolismo , Dano ao DNA , Polarização de Fluorescência/métodos , Ligação Proteica/efeitos dos fármacos , Ligação Proteica/genética , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Proteína de Replicação A/genética , Proteína de Replicação A/metabolismo , Proteína de Xeroderma Pigmentoso Grupo A/genética , Proteína de Xeroderma Pigmentoso Grupo A/metabolismo
7.
J Biol Chem ; 294(15): 5914-5922, 2019 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-30808711

RESUMO

Embryonic stem cells can self-renew and differentiate, holding great promise for regenerative medicine. They also employ multiple mechanisms to preserve the integrity of their genomes. Nucleotide excision repair, a versatile repair mechanism, removes bulky DNA adducts from the genome. However, the dynamics of the capacity of nucleotide excision repair during stem cell differentiation remain unclear. Here, using immunoslot blot assay, we measured repair rates of UV-induced DNA damage during differentiation of human embryonic carcinoma (NTERA-2) cells into neurons and muscle cells. Our results revealed that the capacity of nucleotide excision repair increases as cell differentiation progresses. We also found that inhibition of the apoptotic signaling pathway has no effect on nucleotide excision repair capacity. Furthermore, RNA-Seq-based transcriptomic analysis indicated that expression levels of four core repair factors, xeroderma pigmentosum (XP) complementation group A (XPA), XPC, XPG, and XPF-ERCC1, are progressively up-regulated during differentiation, but not those of replication protein A (RPA) and transcription factor IIH (TFIIH). Together, our findings reveal that increase of nucleotide excision repair capacity accompanies cell differentiation, supported by the up-regulated transcription of genes encoding DNA repair enzymes during differentiation of two distinct cell lineages.


Assuntos
Diferenciação Celular , Reparo do DNA , Células-Tronco de Carcinoma Embrionário/metabolismo , Células Musculares/metabolismo , Proteínas de Neoplasias/metabolismo , Neurônios/metabolismo , Linhagem Celular Tumoral , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Células-Tronco de Carcinoma Embrionário/patologia , Endonucleases/genética , Endonucleases/metabolismo , Humanos , Células Musculares/patologia , Proteínas de Neoplasias/genética , Neurônios/patologia , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Proteína de Replicação A/genética , Proteína de Replicação A/metabolismo , Fator de Transcrição TFIIH/genética , Fator de Transcrição TFIIH/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Proteína de Xeroderma Pigmentoso Grupo A/genética , Proteína de Xeroderma Pigmentoso Grupo A/metabolismo
8.
Artigo em Inglês | MEDLINE | ID: mdl-30744808

RESUMO

OBJECTIVE: The base excision repair (BER) pathway and nucleotide excision repair (NER) pathway play important roles in the repair of benzene-induced genetic damage, and the effects of polymorphisms in these pathways on genetic damage and global DNA methylation are of great interest. METHODS: Ten single nucleotide polymorphisms (SNPs) in the BER (XRCC1: rs25489, rs25487; APE1: rs1130409) and NER pathways (XPA: rs1800975; XPC: rs2228000, rs2228002; XPD: rs13181, rs1799793; XPG: rs17655; ERCC1: rs3212986) were analyzed by a Kompetitive allele-specific PCR (KASP) assay to find associations with cytokinesis-block micronucleus (MN) frequency and global DNA methylation in 294 shoe factory workers and 102 control participants. RESULTS: Workers who possessed the following genotypes were associated with high MN frequency: rs25487 AA (FR (95% CI): 1.50 (1.16,1.9), p = 0.002, reference GG); rs1130409 GG (FR (95% CI): 1.28 (1.05,1.55), p = 0.010, reference TT); rs17655 GC (FR (95% CI): 1.18 (1.02,1.38), p = 0.038, reference GG); and rs3212986 TT (FR (95% CI): 1.55 (1.31,1.83), p < 0.001, reference GG). Workers with four and three mutant alleles showed 3.72-fold (OR (95% CI): 3.72 (1.34, 10.03), p = 0.009) and 2.48-fold (OR (95% CI): 2.48 (1.27, 4.88), p = 0.008) increased risk of genetic damage compared with workers with no or one mutant allele, and a dose-response relationship was found by the trend test (p = 0.006). The rs1130409 variant allele (GG+GT) was associated with low global DNA methylation (ß=-0.20, 95% CI: -0.42, 0.03, p = 0.045). CONCLUSION: In benzene-exposed workers, BER and NER pathway polymorphism haplotypes are associated with different levels of chromosome damage and had little effect on global DNA methylation.


Assuntos
Benzeno/efeitos adversos , Biomarcadores/análise , Dano ao DNA , Metilação de DNA , Reparo do DNA , Exposição Ocupacional/efeitos adversos , Polimorfismo de Nucleotídeo Único , Proteína 1 Complementadora Cruzada de Reparo de Raio-X/metabolismo , Adulto , Estudos de Casos e Controles , DNA Liase (Sítios Apurínicos ou Apirimidínicos)/genética , Proteínas de Ligação a DNA/genética , Endonucleases/genética , Genoma Humano , Haplótipos , Humanos , Masculino , Testes para Micronúcleos , Proteínas Nucleares/genética , Prognóstico , Fatores de Transcrição/genética , Proteína 1 Complementadora Cruzada de Reparo de Raio-X/genética , Proteína de Xeroderma Pigmentoso Grupo A/genética , Proteína Grupo D do Xeroderma Pigmentoso/genética
9.
Acta Crystallogr F Struct Biol Commun ; 75(Pt 1): 62-66, 2019 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-30605127

RESUMO

Human xeroderma pigmentosum complementation group A (XPA) is a scaffold protein that plays significant roles in DNA-damage verification and in recruiting downstream endonucleases to facilitate the repair of DNA lesions in nucleotide-excision repair. XPA98-219 (residues 98-219) has been identified as a DNA-binding domain and has been extensively studied in the last two decades. However, the most recent studies have redefined the DNA-binding domain as XPA98-239 (residues 98-239); it exerts a remarkably higher DNA-binding affinity than XPA98-219 and has a binding affinity that is quite similar to that of the full-length protein. Here, the production, crystallization and structure solution of human XPA98-239 are described. Crystals were obtained using a precipitant composed of 1.8 M ammonium citrate tribasic pH 7.0. Native X-ray diffraction data and zinc single-wavelength anomalous diffraction (SAD) data were collected to 1.93 and 2.06 Šresolution, respectively. The crystals belonged to space group P3, with unit-cell parameters a = 67.1, b = 67.1, c = 35.6 Å, γ = 120.0°. Crystal-content analysis showed the presence of one molecule in the asymmetric unit, corresponding to a Matthews coefficient of 2.65 Å3 Da-1 and a solvent content of 53.6%. The initial phases were solved and the structure model was automatically built by zinc SAD using the AutoSol program. The initial structure model covered 119 of 142 residues in the asymmetric unit, with an Rwork of 22.15% and an Rfree of 25.82%. Compared with a previously obtained truncated solution NMR structure of XPA (residues 98-210), a 19-residue C-terminal extension (residues 211-229, corresponding to 10 of the 20 extra C-terminal residues in the redefined domain for enhanced DNA binding) was contained in this initial model. Refinement of the atomic coordinates of XPA is ongoing.


Assuntos
DNA/química , Proteína de Xeroderma Pigmentoso Grupo A/química , Sequência de Aminoácidos , Sítios de Ligação , Clonagem Molecular , Cristalização , Cristalografia por Raios X , DNA/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Expressão Gênica , Vetores Genéticos/química , Vetores Genéticos/metabolismo , Humanos , Modelos Moleculares , Ligação Proteica , Conformação Proteica em alfa-Hélice , Domínios e Motivos de Interação entre Proteínas , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Proteína de Xeroderma Pigmentoso Grupo A/genética , Proteína de Xeroderma Pigmentoso Grupo A/metabolismo
10.
Carcinogenesis ; 40(4): 580-591, 2019 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-30418489

RESUMO

Transforming growth factor beta (TGFß) is multifunctional cytokine that is involved in the coordination and regulation of many cellular homeostatic processes. Compromised TGFß activity has been attributed to promotion of human cancers. Recent studies have identified a role for TGFß in response to radiation-induced DNA damage, suggesting a link between TGFß and the DNA damage response with implications for cancer development. In this study, the effects of TGFß on promoting the repair of bulky DNA damage, through modulation of nucleotide excision repair (NER), were investigated. We show that treatment of cells with exogenous TGFß leads to enhanced repair of DNA damage formed by polycyclic aromatic hydrocarbons and ultraviolet-C radiation; similarly, cells with constitutively activated endogenous TGFß signaling show comparable responses. This effect of TGFß is independent of the cell cycle. The response to TGFß is decreased in cells that have compromised TGFß signaling through RNA interference of Smad4 and is decreased in NER-deficient cells and cells with compromised NER through RNA interference of excision repair cross-complementing group 1 (ERCC1). Increased interaction and nuclear localization of ERCC1/xeroderma pigmentosum (XP) F and ERCC1/XPA proteins is observed after TGFß treatment. Our study represents the first experimental evidence of a role for TGFß in the repair of bulky DNA damage resulting from promotion of the interaction and localization of repair protein complexes involved in the incision step of NER.


Assuntos
Carcinoma Hepatocelular/patologia , Dano ao DNA , Reparo do DNA , Proteínas de Ligação a DNA/metabolismo , Endonucleases/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Proteína de Xeroderma Pigmentoso Grupo A/metabolismo , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Proteínas de Ligação a DNA/genética , Endonucleases/genética , Células Hep G2 , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Transdução de Sinais , Fator de Crescimento Transformador beta1/genética , Proteína de Xeroderma Pigmentoso Grupo A/genética
11.
Pathol Oncol Res ; 25(3): 1035-1045, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30066234

RESUMO

The combination of cisplatin and gemcitabine is still one of the most frequently used first-line chemotherapy scheme in patients with advanced non-small cell lung cancer (NSCLC), in which tyrosine kinase inhibitors (TKIs) cannot be administered. Unfortunately, more than half of the patients have no benefit from chemotherapy but are still exposed to its toxic effects. Therefore, single nucleotide polymorphisms (SNPs) in the genes involved in nucleotide excision repair (NER) mechanism may be a potential predictive factor of efficiency of cytostatic based chemotherapy. The aim of the study was to evaluate the correlation between SNPs of the genes involved in NER mechanism and the effectiveness of chemotherapy based on cisplatin and gemcitabine in patients with advanced NSCLC. The study group included 91 NSCLC patients treated with first-line chemotherapy using cisplatin and gemcitabine. Genotyping was carried out using a mini-sequencing technique (SNaPshot™ PCR). The median progression-free survival (PFS) was significantly shorter in carriers of CC genotype of the XPD/ERCC2 (2251A > C) gene compared to patients with AA/AC genotypes (2 vs. 4.5 months; p = 0.0444; HR = 3.19, 95%CI:1.03-9.91). Rare CC genotype of XPD/ERCC2 gene, may be considered as an unfavorable predictive factor for chemotherapy based on cisplatin and gemcitabine in patients with advanced NSCLC.


Assuntos
Adenocarcinoma/patologia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Biomarcadores Tumorais/genética , Carcinoma de Células Grandes/patologia , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma de Células Escamosas/patologia , Neoplasias Pulmonares/patologia , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/genética , Adulto , Idoso , Carcinoma de Células Grandes/tratamento farmacológico , Carcinoma de Células Grandes/genética , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/genética , Cisplatino/administração & dosagem , Proteínas de Ligação a DNA/genética , Desoxicitidina/administração & dosagem , Desoxicitidina/análogos & derivados , Endonucleases/genética , Feminino , Seguimentos , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Masculino , Pessoa de Meia-Idade , Proteínas Nucleares/genética , Prognóstico , Taxa de Sobrevida , Fatores de Transcrição/genética , Proteína de Xeroderma Pigmentoso Grupo A/genética , Proteína Grupo D do Xeroderma Pigmentoso/genética
12.
JAMA Dermatol ; 155(1): 72-78, 2019 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-30516811

RESUMO

Importance: Wide use of genomic sequencing to diagnose disease has raised concern about the extent of genotype-phenotype correlations. Objective: To correlate disease-associated allele frequencies with expected and reported prevalence of clinical disease. Design, Setting, and Participants: Xeroderma pigmentosum (XP), a recessive, cancer-prone, neurocutaneous disorder, was used as a model for this study. From January 1, 2017, to May 4, 2018, the Human Gene Mutation Database and a cohort of patients at the National Institutes of Health were searched and screened to identify reported mutations associated with XP. The clinical phenotype of these patients was confirmed from reports in the literature and National Institutes of Health medical records. The genetically predicted prevalence of disease based on frequency of known pathogenic mutations was compared with the prevalence of patients clinically diagnosed with phenotypic XP. Exome sequencing of more than 200 000 alleles from the Genome Aggregation Database, the National Cancer Institute Division of Cancer Epidemiology and Genetics database of healthy controls, and an Inova Hospital Study database was used to investigate the frequencies of these mutations in the general population. Main Outcomes and Measures: Listing of all reported mutations associated with XP, their frequencies in 3 large exome sequence databases, determination of the number of patients in the United States with XP using modeling equations, and comparison of the observed and reported numbers of patients with XP with specific mutations. Results: A total of 156 pathogenic missense and nonsense mutations associated with XP were identified in the National Institutes of Health cohort and the Human Gene Mutation Database. The Genome Aggregation Database provided frequency data for 65 of these mutations, with a total allele frequency of 1.13%. The XPF (ERCC4) mutation, p.P379S, had an allele frequency of 0.4%, and the XPC mutation, p.P334H, had an allele frequency of 0.3%. With the Hardy-Weinberg equation, it was determined that there should be more than 8000 patients who are homozygous for these mutations in the United States. In contrast, only 3 patients with XP were reported as having the XPF mutation, and 1 patient was reported as having the XPC mutation. Conclusions and Relevance: The findings from this study suggest that clinicians should approach large genomic databases with caution when trying to correlate the clinical implications of genetic variants with the prevalence of disease risk. Unsuspected mutations in known genes with a predisposition for skin cancer may be responsible for some of the high frequency of skin cancers in the general population.


Assuntos
Big Data , Reparo do DNA/genética , Mutação , Proteína de Xeroderma Pigmentoso Grupo A/genética , Xeroderma Pigmentoso/genética , Adulto , Análise Mutacional de DNA , Feminino , Frequência do Gene , Genótipo , Humanos , Masculino , Fenótipo , Prevalência , Estudos Retrospectivos , Estados Unidos/epidemiologia , Xeroderma Pigmentoso/epidemiologia
13.
J Cancer Res Ther ; 14(Supplement): S1173-S1177, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30539866

RESUMO

Aim of the Study: Several studies have evaluated the correlation between xeroderma pigmentosum Group A (XPA) A23G polymorphism (rs 1800975) and esophageal cancer in Chinese people. However, the results are inconsistent. To assess the effects of XPA A23G variants on the risk for development of esophageal cancer in the Chinese population, a meta-analysis was performed. Materials and Methods: Studies were identified using PubMed and Chinese databases through December 2015. The associations were assessed with pooled odds ratios (ORs) and 95% confidence intervals (95% CIs). Results: This meta-analysis identified seven studies including 1514 esophageal cancer cases and 2120 controls. In the overall analysis, no significant association between XPA A23G polymorphism and esophageal cancer was found in the Chinese population. In the subgroup analyses by geographic area(s) and source of controls, significant results were only found in studies with hospital-based controls (GG vs. AA: OR = 0.42, 95% CI = 0.28-0.62; GG vs. AA + AG: OR = 0.55, 95% CI = 0.39-0.78; GG + AG vs. AA: OR = 0.54, 95% CI = 0.40-0.72; G vs. A: OR = 0.61, 95% CI = 0.50-0.75). Conclusions: This meta-analysis suggested that XPA A23G gene polymorphism may be one low-penetrant risk factor for esophageal cancer in Chinese individuals.


Assuntos
Grupo com Ancestrais do Continente Asiático/genética , Neoplasias Esofágicas/genética , Predisposição Genética para Doença , Proteína de Xeroderma Pigmentoso Grupo A/genética , Humanos , Razão de Chances , Penetrância , Polimorfismo de Nucleotídeo Único , Fatores de Risco
14.
Pregnancy Hypertens ; 14: 145-149, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30527102

RESUMO

Our study aimed to investigate the association between polymorphism of three core genes belonging to NER pathway and preeclampsia (PE) risk in Chinese Han Women. The DNA used in our experiment was extracted from 1004 cases and 1274 normal pregnant women. All single nucleotide polymorphisms (SNPs) were analyzed with TaqMan allelic discrimination real-time PCR. Our findings showed the genotype and allele frequency of XPA rs1800975, XPF rs1799801, XPG rs17655 in case group has no significant differences compared with control group (all P > 0.05). However, we found the genotype of rs1799801 in the control group was significantly different from severe PE group in cases (P < 0.05). Moreover, the genotype frequency of rs1800975 and rs1799801in the early-onset PE were significantly different from control group (all P < 0.05). These results indicated that the polymorphism of the three SNPs had no significant correlation with risk of PE as a whole. However, we found XPA rs1800975 played a role in the development of early-onset PE, and XPF rs1799801 was associated with severe PE and early-onset PE. So we may need to continue to increase the sample size to clarify their relationship.


Assuntos
Reparo do DNA , Proteínas de Ligação a DNA/genética , Endonucleases/genética , Predisposição Genética para Doença , Proteínas Nucleares/genética , Pré-Eclâmpsia/genética , Fatores de Transcrição/genética , Proteína de Xeroderma Pigmentoso Grupo A/genética , Adulto , Grupo com Ancestrais do Continente Asiático , Estudos de Casos e Controles , China , Feminino , Humanos , Polimorfismo de Nucleotídeo Único , Gravidez , Reação em Cadeia da Polimerase em Tempo Real , Índice de Gravidade de Doença
15.
J Hum Genet ; 63(11): 1181-1184, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30089811

RESUMO

This study was designed to learn if asymptomatic heterozygotes with mutations in a DNA repair gene are at an increased risk for cancer. To examine this, we focused on carriers of an XPA founder mutation because the frequency of xeroderma pigmentosum (XP) patients is much greater among Japanese than Caucasians, more than half of Japanese XP patients are affected at the XPA gene, and the majority of XP-A patients carry the same founder mutation in the XPA gene. Here we show that the frequency of XPA heterozygote was 14/1698 (0.8%) in cancer-free controls, and the corresponding frequency in patients with nonmelanocytic skin cancer that developed in sun-exposed areas was 11/440 (2.5%, OR = 3.08, p = 0.0097) for basal cell carcinoma, and 3/272 (1.1%, OR = 1.34, p = 0.72) for squamous cell carcinoma. These results suggest a moderately elevated risk for skin cancer among XPA heterozygotes.


Assuntos
Adenocarcinoma/genética , Grupo com Ancestrais do Continente Asiático/genética , Carcinoma de Células Escamosas/genética , Efeito Fundador , Heterozigoto , Mutação , Neoplasias Cutâneas/genética , Proteína de Xeroderma Pigmentoso Grupo A/genética , Idoso , Feminino , Humanos , Japão , Masculino , Pessoa de Meia-Idade
17.
Photochem Photobiol ; 94(5): 1077-1081, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29968917

RESUMO

Voriconazole is an antifungal agent and used as a prophylactic measure, especially in immunocompromised patients. However, there have been several reports of its adverse reactions, namely photosensitivity with intense inflammatory rashes and subsequent skin cancer development. To assess the effects of photosensitizing drugs voriconazole and hydrochlorothiazide (HCTZ) on the enhancement of UV-induced inflammatory responses and UV-induced tumorigenesis, we utilized Xpa-knockout mice, which is DNA repair-deficient and more susceptible to UV-induced inflammation and tumor development than wild-type mice. Administration of voriconazole prior to broadband UVB exposure significantly upregulated multiple inflammatory cytokines compared with the vehicle- or HCTZ-administered groups. Voriconazole administration along with chronic UVB exposure produced significantly higher number of skin tumors than HCTZ or vehicle in Xpa-knockout mice. Furthermore, the investigation of UVB-induced DNA damage using embryonic fibroblasts of Xpa-knockout mice revealed a significantly higher 8-oxo-7,8-dihydroguanine level in cells treated with voriconazole N-oxide, a voriconazole-metabolite during UV exposure. The data suggest that voriconazole plus UVB-induced inflammatory response may be related to voriconazole-induced skin phototumorigenesis.


Assuntos
Hidroclorotiazida/efeitos adversos , Inflamação/induzido quimicamente , Neoplasias Induzidas por Radiação/patologia , Transtornos de Fotossensibilidade/induzido quimicamente , Neoplasias Cutâneas/etiologia , Raios Ultravioleta , Voriconazol/efeitos adversos , Proteína de Xeroderma Pigmentoso Grupo A/genética , Animais , Antifúngicos/efeitos adversos , Anti-Hipertensivos/efeitos adversos , Cocarcinogênese , Citocinas/metabolismo , Mediadores da Inflamação/metabolismo , Camundongos , Camundongos Knockout , Neoplasias Cutâneas/genética
18.
Biomarkers ; 23(8): 735-741, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29871536

RESUMO

PURPOSE: Examine the association between bulky DNA adduct levels in colon mucosa and colorectal adenoma prevalence, and explore the correlation between adduct levels in leukocytes and colon tissue. METHODS: Bulky DNA adduct levels were measured using 32P-postlabelling in biopsies of normal-appearing colon tissue and blood donated by 202 patients. Multivariable logistic regression was used to examine associations between DNA adducts, and interactions of DNA adduct-DNA repair polymorphisms, with the prevalence of colorectal adenomas. Correlation between blood and tissue levels of DNA adducts was evaluated using Spearman's correlation coefficient. RESULTS: An interaction between bulky DNA adduct levels and XPA rs1800975 on prevalence of colorectal adenoma was observed. Among individuals with lower DNA repair activity, increased DNA adduct levels were associated with increased colorectal adenoma prevalence (OR = 1.41 per SD increase, 95%CI: 0.92-2.18). Conversely, among individuals with normal DNA activity, an inverse association was observed (OR = 0.60 per SD increase, 95%CI: 0.34-1.07). Blood and colon DNA adduct levels were inversely correlated (ρ = -0.20). CONCLUSIONS: Among genetically susceptible individuals, higher bulky DNA adducts in the colon was associated with the prevalence of colorectal adenomas. The inverse correlation between blood and colon tissue measures demonstrates the importance of quantifying biomarkers in target tissues.


Assuntos
Neoplasias Colorretais/etiologia , Adutos de DNA/análise , Mucosa Intestinal/química , Adenoma/etiologia , Adulto , Feminino , Predisposição Genética para Doença , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo Genético , Prevalência , Proteína de Xeroderma Pigmentoso Grupo A/genética
19.
Medicine (Baltimore) ; 97(26): e11276, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29953005

RESUMO

BACKGROUND: The association of XPA rs1800975 polymorphism with breast cancers has been reported in several studies, but the results were conflicting. In order to analyze the association between XPA rs1800975 polymorphism and the risk of breast cancer, a meta-analysis was performed in the present study. METHODS: The literature search for relevant studies was conducted in PubMed, Embase, Cochrane Library, China National Knowledge Infrastructure (CNKI), and Wanfang Med Online databases. The odds ratios (ORs) and their corresponding 95% confidence intervals (95% CIs) were calculated using fixed-effect/random-effects models by the STATA 12.0 software. The sources of heterogeneity were analyzed by subgroup analysis. RESULTS: Six case-control studies involving 5069 subjects (2338 patients and 2731 healthy controls) were included in the present meta-analysis. In the pooled analysis, no obvious association was found between XPA rs1800975 polymorphism and the risk of breast cancer in all genetic models. However, in subgroup analysis based on ethnicity, XPA rs1800975 polymorphism was found to be related to decreased breast cancer risk in non-Asians in the recessive model (OR = 0.80, 95% CI = 0.64-1.00, P = .045). Moreover, source of control subgroup analysis demonstrated that XPA rs1800975 polymorphism might decrease the risk of breast cancer in population-based group in the recessive model (OR = 0.80, 95% CI = 0.64-1.00, P = .045). CONCLUSION: XPA rs1800975 polymorphism may decrease the risk of breast cancer in both non-Asians and population-based patients. Large sample size and well-designed study is needed for further assessing the role of XPA polymorphism in breast cancer risk.


Assuntos
Neoplasias da Mama/genética , Proteína de Xeroderma Pigmentoso Grupo A/genética , Grupo com Ancestrais do Continente Asiático , Estudos de Casos e Controles , China , Feminino , Predisposição Genética para Doença , Humanos , Polimorfismo de Nucleotídeo Único
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