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We have discovered a new mode of reactivity of 1-thiosugars in the presence of Cu(II) or Co(II) for a stereoselective O-glycosylation reaction. The process involves the use of a catalytic amount of Cu(acac)2 or Co(acac)2 and Ag2CO3 as an oxidant in α,α,α-trifluorotoluene. Moreover, this protocol turned out to have a broad scope, allowing the preparation of a wide range of complex substituted O-glycoside esters in good to excellent yields with an exclusive 1,2-trans-selectivity. The late-stage modification of pharmaceuticals by this method was also demonstrated. To obtain a closer insight into the reaction mechanism, cyclic voltammetry was performed.
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High-risk mucosal types of human papillomavirus (HPV) cause anogenital and oropharyngeal cancers, whereas cutaneous types (e.g. HPV8 and 77) are suspected to be involved in non-melanoma skin cancer. The antibody response to HPVs is a key determinant of protective immunity, but not all infected individuals seroconvert. Genetic variability of the host may have large impact on seroconversion. A previous genome-wide association study (GWAS) has identified a susceptibility locus (rs41270488) for HPV8 seropositivity within the major histocompatibility complex (MHC) region. To further study this locus, we imputed alleles at classical leukocyte antigen (HLA) loci using HLA*IMP:02 with a reference panel from the HapMap Project and the 1958 Birth Cohort, and conducted an integrated analysis among 4811 central European subjects to assess the contribution of classical HLA alleles and gene copy number variation (CNV) at the hypervariable DRB locus within the MHC region to HPV seropositivity at both the individual HPV type level and the phylogenetic species level. Our study provides evidence that the association noted between rs41270488 and HPV8 seropositivity is driven by two independent variants, namely DQB1*0301 [odds ratio (OR) = 1.51, 95% confidence interval (CI) = 1.36-1.68, P = 1.0 × 10(-14)] and DRB1*1101 (OR = 1.89, 95%CI = 1.57-2.28, P = 1.5 × 10(-11)) within the HLA class II region. Additionally, we identified two correlated alleles DRB1*0701 (OR = 1.67, 95%CI = 1.41-1.98, P = 2.6 × 10(-9)) and DQA1*0201 (OR = 1.67, 95%CI = 1.38-1.93, P = 1.7 × 10(-8)), to be associated with HPV77 seropositivity. Comparable results were observed through imputation using SNP2HLA with another reference panel from the Type 1 diabetes Genetics Consortium. This study provides support for an important role of HLA class II alleles in antibody response to HPV infection.
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Alelos , Predisposição Genética para Doença , Variação Genética , Complexo Principal de Histocompatibilidade/genética , Infecções por Papillomavirus/genética , Estudos de Casos e Controles , Feminino , Antígenos HLA/genética , Haplótipos , Humanos , Desequilíbrio de Ligação , Masculino , Razão de Chances , Papillomaviridae/classificação , Papillomaviridae/genética , Infecções por Papillomavirus/virologia , Polimorfismo de Nucleotídeo ÚnicoRESUMO
An efficient thioglycosylation of C(sp2 )-H bonds with thiosugars has been established for the first time. Using only Cu(OAc)2 â H2 O as a catalyst and Ag2 CO3 as an additive in DMSO, the protocol proved to have broad scope, and a variety of complex thioglycosides have been prepared in good yields with exclusive ß-selectivity.
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Genome-wide association studies (GWAS) have been successful in identifying common genetic variation involved in susceptibility to etiologically complex disease. We conducted a GWAS to identify common genetic variation involved in susceptibility to upper aero-digestive tract (UADT) cancers. Genome-wide genotyping was carried out using the Illumina HumanHap300 beadchips in 2,091 UADT cancer cases and 3,513 controls from two large European multi-centre UADT cancer studies, as well as 4,821 generic controls. The 19 top-ranked variants were investigated further in an additional 6,514 UADT cancer cases and 7,892 controls of European descent from an additional 13 UADT cancer studies participating in the INHANCE consortium. Five common variants presented evidence for significant association in the combined analysis (p ≤ 5 × 10â»7). Two novel variants were identified, a 4q21 variant (rs1494961, pâ=â1×10â»8) located near DNA repair related genes HEL308 and FAM175A (or Abraxas) and a 12q24 variant (rs4767364, p =2 × 10â»8) located in an extended linkage disequilibrium region that contains multiple genes including the aldehyde dehydrogenase 2 (ALDH2) gene. Three remaining variants are located in the ADH gene cluster and were identified previously in a candidate gene study involving some of these samples. The association between these three variants and UADT cancers was independently replicated in 5,092 UADT cancer cases and 6,794 controls non-overlapping samples presented here (rs1573496-ADH7, p = 5 × 10â»8); rs1229984-ADH1B, p = 7 × 10â»9; and rs698-ADH1C, p = 0.02). These results implicate two variants at 4q21 and 12q24 and further highlight three ADH variants in UADT cancer susceptibility.
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Estudo de Associação Genômica Ampla , Neoplasias de Cabeça e Pescoço/genética , Adulto , Idoso , Aldeído Desidrogenase/genética , Biomarcadores Tumorais/genética , Feminino , Frequência do Gene , Predisposição Genética para Doença , Variação Genética , Neoplasias de Cabeça e Pescoço/enzimologia , Neoplasias de Cabeça e Pescoço/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Grupos Raciais , Fatores de RiscoRESUMO
Over 100 single nucleotide polymorphisms (SNP) are validated in the TP53 tumor suppressor gene. They define haplotypes, which may differ in their activities. Therefore, mutation in cancer may occur at different rates depending upon haplotypes. However, these associations may be masked by differences in mutations types and causes of mutagenesis. We have analyzed the associations between 19 SNPs spanning the TP53 locus and a single specific aflatoxin-induced TP53 mutation (R249S) in 85 in hepatocellular carcinoma cases and 132 controls from Thailand. An association with R249S mutation (P = 0.007) was observed for a combination of two SNPs (rs17882227 and rs8064946) in a linkage disequilibrium block extending from upstream of exon 1 to the first half of intron 1. This domain contains two coding sequences overlapping with TP53 (WRAP53 and Hp53int1) suggesting that sequences in TP53 intron 1 encode transcripts that may modulate R249S mutation rate in HCC.
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Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/genética , Mutação , Proteína Supressora de Tumor p53/genética , Adulto , Carcinoma Hepatocelular/induzido quimicamente , Estudos de Casos e Controles , DNA de Neoplasias/sangue , DNA de Neoplasias/genética , Feminino , Estudos de Associação Genética , Humanos , Íntrons , Desequilíbrio de Ligação , Cirrose Hepática/genética , Neoplasias Hepáticas/induzido quimicamente , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo ÚnicoRESUMO
High-risk α mucosal types of human papillomavirus (HPV) cause anogenital and oropharyngeal cancers, whereas ß cutaneous HPV types (e.g. HPV8) have been implicated in non-melanoma skin cancer. Although antibodies against the capsid protein L1 of HPV are considered as markers of cumulative exposure, not all infected persons seroconvert. To identify common genetic variants that influence HPV seroconversion, we performed a two-stage genome-wide association study. Genome-wide genotyping of 316 015 single nucleotide polymorphisms was carried out using the Illumina HumanHap300 BeadChip in 4811 subjects from a central European case-control study of lung, head and neck and kidney cancer that had serology data available on 13 HPV types. Only one association met genome-wide significance criteria, namely that between HPV8 seropositivity and rs9357152 [odds ratio (OR) = 1.37, 95% confidence interval (CI) = 1.24-1.50 for the minor allele G; P=1.2 × 10(-10)], a common genetic variant (minor allele frequency=0.33) located within the major histocompatibility complex (MHC) II region at 6p21.32. This association was subsequently replicated in an independent set of 2344 subjects from a Latin American case-control study of head and neck cancer (OR=1.35, 95% CI=1.18-1.56, P=2.2 × 10(-5)), yielding P=1.3 × 10(-14) in the combined analysis (P-heterogeneity=0.87). No heterogeneity was noted by cancer status (controls/lung cancer cases/head and neck cancer cases/kidney cancer cases). This study provides a proof of principle that genetic variation plays a role in antibody reactivity to HPV infection.
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Estudo de Associação Genômica Ampla , Soropositividade para HIV/genética , Anticorpos Anti-HIV/imunologia , Soropositividade para HIV/imunologia , Humanos , Complexo Principal de Histocompatibilidade/genética , Polimorfismo de Nucleotídeo Único/genética , Reprodutibilidade dos Testes , População Branca/genéticaRESUMO
OBJECTIVES: Non-adherence to anti-infective therapy contributes to treatment failure and the emergence of bacterial resistance. This study aimed to assess at-home adherence, by paediatric patients, to oral anti-infective (OAI) therapy prescribed for treatment of acute infections and to explore the factors contributing to non-adherence. METHODS: This prospective descriptive study involved French-speaking patients under 16 years of age who were discharged with one or more OAIs prescribed for home administration for a maximum of 30 days. Telephone surveys were used to assess overall adherence, which consisted of primary adherence (patient's ability to procure the medication) and secondary adherence (patient's ability to take the treatment as prescribed). RESULTS: Overall, 51.7% (30/58) of patients were adherent to OAI therapy, with 100% primary adherence (n=69/69) and 51.7% secondary adherence (n=30/58). On average, patients took 98% of the total number of doses prescribed, and non-adherence was related mostly to not following medication administration schedules (63.3% of patients followed the exact schedule). Indeed, the adherence rate for patients taking one or two doses per day was twice the rate for patients taking more than two doses per day (81.8% vs 44.7%, p=0.043). CONCLUSIONS: Half of the paediatric patients treated for acute infections were non-adherent to OAI therapy at home. Interventions are needed to improve this situation.
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Anti-Infecciosos , Adesão à Medicação , Criança , Humanos , Alta do Paciente , Estudos Prospectivos , Quebeque , Anti-Infecciosos/administração & dosagem , Anti-Infecciosos/uso terapêutico , Adesão à Medicação/estatística & dados numéricos , Administração OralRESUMO
BACKGROUND: The incidence of nasopharyngeal carcinoma (NPC) varies substantially worldwide, with an endemic pocket in Southeast Asia. METHOD: We assessed lifestyle and genetic factors in relation to NPC risk among 681 NPC cases and 1,078 controls from Thailand. Evaluated lifestyle factors included traditionally preserved foods, tobacco smoking, betel quid chewing, and alcohol consumption. Genetic factors included six variants implicated in a previous a genome-wide association study (GWAS) of NPC and three variants residing near the CHRNA3 and TERT genes that were linked to lung cancer risk in Asian populations. Odds ratios (OR) and 95 % confidence intervals (95 % CI) were estimated using unconditional logistic regression. RESULTS: Frequent consumption of fermented vegetables was associated with increased NPC risk (OR of consumption ≥weekly vs. ≤rare 1.78, 95 % CI 1.24-2.55, p (trend) = 0.005), as was tobacco smoking (p (trend) < 0.001), former and current smokers displaying OR of 1.57 (95 % CI 1.10-2.30) and 2.00 (95 % CI 1.48-2.71) compared to never smokers, respectively. Four out of six genetic variants implicated in the recent NPC GWAS were associated with NPC risk (p (trend) ≤ 0.03), as well as two variants (rs402710 and rs2736098) on the TERT locus at 5p15.33 (p = 0.004 and p = 0.04, respectively). CONCLUSIONS: These results strengthen our previous observation that tobacco smoking is an important risk factor of NPC in this population. Four out of six genetic variants identified in a recent NPC GWAS were confirmed, and the association noted with variants on 5p15.33 suggests that this locus is involved in NPC susceptibility, representing a novel finding in NPC epidemiology.
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Neoplasias Nasofaríngeas/epidemiologia , Neoplasias Nasofaríngeas/genética , Fumar/epidemiologia , Fumar/genética , Adulto , Carcinoma , Feminino , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas/diagnóstico , Medição de Risco , Fatores de Risco , Tailândia/epidemiologiaRESUMO
Background: Knowledge transfer helps health care staff to be competent, well informed, and up to date. It also contributes to adherence to standards and best practices. Objectives: To design, implement, and evaluate an escape game based on a selection of Accreditation Canada required organizational practices (ROPs). Methods: This prospective descriptive study involved nurses and pharmacists in a health care centre. An escape game based on 6 ROPs was designed. The game was played by teams of participants in a patient room within the centre, with each game lasting 25 minutes. Participants' satisfaction with various aspects of their experience was assessed. Results: A total of 200 people (52 teams) participated in the escape game. About half of the teams (n = 28) completed the game within the allotted time (average completion time 20 minutes, 53 seconds; standard deviation [SD] 2 minutes, 45 seconds). On average, 1.32 (SD 0.88) clues were provided to successful teams and 1.88 (SD 0.95) to unsuccessful teams. Participants were very satisfied with their experience. However, members of unsuccessful teams had significantly lower agreement that the escape game was relevant to their practice and that it was an effective method of communication. Conclusions: An escape game based on a selection of ROPs was successfully implemented as part of the hospital's preparation for an accreditation visit. Use of an escape game as a knowledge transfer tool was appreciated by the staff.
Contexte: La transmission des connaissances aide le personnel de la santé à être compétent, bien informé et à jour. Elle contribue également au respect des normes et des meilleures pratiques. Objectifs: Concevoir, mettre en Åuvre et évaluer un jeu d'évasion basé sur une sélection de pratiques organisationnelles requises (POR) d'Agrément Canada. Méthodes: Des infirmiers et des pharmaciens d'un centre de santé ont participé à cette étude prospective descriptive. Un jeu d'évasion basé sur 6 POR a été conçu. Des équipes de participants y ont joué dans une chambre de patient au sein du centre, chaque partie durant 25 minutes. La satisfaction des participants à l'égard de divers aspects de leur expérience a été évaluée. Résultats: Au total, 200 personnes (52 équipes) y ont participé. Environ la moitié des équipes (n = 28) ont terminé le jeu dans le temps imparti (temps moyen d'achèvement 20 minutes, 53 secondes ; écart type [ET] 2 minutes, 45 secondes). En moyenne, 1,32 indice (ET 0,88) a été remis aux équipes qui l'ont réussi et 1,88 (ET 0,95) aux équipes qui ont échoué. Les participants étaient très satisfaits de leur expérience. Cependant, les membres des équipes ayant échoué étaient significativement moins d'accord sur le fait que le jeu d'évasion était pertinent pour l'exercice de leur profession et qu'il s'agissait d'une méthode de communication efficace. Conclusions: Un jeu d'évasion basé sur une sélection de POR a été mis en place avec succès dans le cadre de la préparation de l'hôpital à une visite d'agrément. L'utilisation d'un jeu d'évasion comme outil de transmission des connaissances a été reçue de manière positive par le personnel.
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Concentrated bud macerates (CBMs) are obtained from meristematic tissues such as buds and young shoots by maceration in a solvent composed of glycerin, water and ethanol (1/1/1/, v/v). Their traditional utilization in gemmotherapy has gained interest in the past years, and the knowledge of their chemical characterization can provide commercial arguments, particularly to secure their quality control. Therefore, an optimized method for phytochemical analysis including glycerol removal by a preliminary solid phase extraction (SPE) followed by compound identification using high performance liquid chromatography coupled with ultra-violet and tandem mass detectors (HPLC-UV-MS2) was developed. This method was applied on 5 CBMs obtained from Alnus glutinosa, Ribesnigrum, Rosmarinus officinalis, Rosa canina and Tilia tomentosa in order to determinate their chemical composition. Their antioxidant effects were also investigated by radical scavenging activity assays (DPPH and ORAC). Glycerol removal improved the resolution of HPLC chemical profiles and allowed us to perform TLC antioxidant screening. Our approach permitted the identification of 57 compounds distributed in eight major classes, three of them being common to all macerates including nucleosides, phenolic acids and glycosylated flavonoids. Quantification of the later class as a rutin equivalent (RE) showed a great disparity between Rosa canina macerate (809 mg RE/L), and the other ones (from 175 to 470 mg RE/L). DPPH and ORAC assays confirmed the great activity of Rosa canina (4857 and 6479 µmol TE/g of dry matter, respectively). Finally, phytochemical and antioxidant analysis of CBMs strengthened their phytomedicinal interest in the gemmotherapy field.
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TCTP protein is a pharmacological target in cancer and TCTP inhibitors such as sertraline have been evaluated in clinical trials. The direct interaction of TCTP with the drugs sertraline and thioridazine has been reported inâ vitro by SPR experiments to be in the â¼30-50â µM Kd range (Amson etâ al. Nature Med 2012), supporting a TCTP-dependent mode of action of the drugs on tumor cells. However, the molecular details of the interaction remain elusive although they are crucial to improve the efforts of on-going medicinal chemistry. In addition, TCTP can be phosphorylated by the Plk-1 kinase, which is indicative of poor prognosis in several cancers. The impact of phosphorylation on TCTP structure/dynamics and binding with therapeutical ligands remains unexplored. Here, we combined NMR, TSA, SPR, BLI and ITC techniques to probe the molecular interactions between TCTP with the drugs sertraline and thioridazine. We reveal that drug binding is much weaker than reported with an apparent â¼mM Kd and leads to protein destabilization that obscured the analysis of the published SPR data. We further demonstrate by NMR and SAXS that TCTP S46 phosphorylation does not promote tighter interaction between TCTP and sertraline. Accordingly, we question the supported model in which sertraline and thioridazine directly interact with isolated TCTP in tumor cells and discuss alternative modes of action for the drugs in light of current literature.
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Antineoplásicos/farmacologia , Sertralina/farmacologia , Tioridazina/farmacologia , Proteína Tumoral 1 Controlada por Tradução/antagonistas & inibidores , Antineoplásicos/química , Relação Dose-Resposta a Droga , Humanos , Ligantes , Estrutura Molecular , Sertralina/química , Relação Estrutura-Atividade , Tioridazina/química , Proteína Tumoral 1 Controlada por Tradução/isolamento & purificação , Proteína Tumoral 1 Controlada por Tradução/metabolismoRESUMO
BACKGROUND: Analysis of candidate genes in individual studies has had only limited success in identifying particular gene variants that are conclusively associated with lung cancer risk. In the International Lung Cancer Consortium (ILCCO), we conducted a coordinated genotyping study of 10 common variants selected because of their prior evidence of an association with lung cancer. These variants belonged to candidate genes from different cancer-related pathways including inflammation (IL1B), folate metabolism (MTHFR), regulatory function (AKAP9 and CAMKK1), cell adhesion (SEZL6) and apoptosis (FAS, FASL, TP53, TP53BP1 and BAT3). METHODS: Genotype data from 15 ILCCO case-control studies were available for a total of 8431 lung cancer cases and 11 072 controls of European descent and Asian ethnic groups. Unconditional logistic regression was used to model the association between each variant and lung cancer risk. RESULTS: Only the association between a non-synonymous variant of TP53BP1 (rs560191) and lung cancer risk was significant (OR = 0.91, P = 0.002). This association was more striking for squamous cell carcinoma (OR = 0.86, P = 6 x 10(-4)). No heterogeneity by center, ethnicity, smoking status, age group or sex was observed. In order to confirm this association, we included results for this variant from a set of independent studies (9966 cases/11,722 controls) and we reported similar results. When combining all these studies together, we reported an overall OR = 0.93 (0.89-0.97) (P = 0.001). This association was significant only for squamous cell carcinoma [OR = 0.89 (0.85-0.95), P = 1 x 10(-4)]. CONCLUSION: This study suggests that rs560191 is associated to lung cancer risk and further highlights the value of consortia in replicating or refuting published genetic associations.
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Predisposição Genética para Doença , Neoplasias Pulmonares/genética , Adulto , Idoso , Feminino , Estudo de Associação Genômica Ampla , Genótipo , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Neoplasias Pulmonares/etiologia , Masculino , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Pessoa de Meia-Idade , Chaperonas Moleculares/genética , Razão de Chances , Proteína 1 de Ligação à Proteína Supressora de Tumor p53RESUMO
BACKGROUND: In the hospital setting, the medication-use system is complex, having more than 50 steps. To assess the compliance of the study organization's medication-use system with established criteria, an annual audit process was developed. OBJECTIVES: The primary objective was to describe the compliance of certain steps in the medication-use system (mainly medication management) in care units and outpatient clinics of a mother and child university hospital centre. The secondary objective was to compare the current results with those of previous audits. METHODS: This cross-sectional descriptive observational study was carried out in summer 2018 in patient care units (n = 34) and outpatient clinics (n = 28) of the study hospital. Data were collected according to an audit matrix. RESULTS: In 2018, the rate of compliance with audit criteria varied between 32% and 100% for the patient care units. Relative to the previous year, the compliance rate remained unchanged for 30 criteria and worsened for 4 criteria. For 35% of the criteria (12/34), compliance was greater than 85%. In 2018, the rate of compliance with audit criteria varied between 0% and 100% for the outpatient clinics. The compliance rate increased for one criterion, remained unchanged for 21 criteria, and worsened for 2 criteria. For 32% of the criteria (9/28), compliance was more than 85%. Thirty-five recommendations were made to the pharmacy and nursing care committee, and a personalized report was sent to managers. CONCLUSIONS: This cross-sectional descriptive observational study reports the degree to which the medication-use system complies with medication management criteria, mainly in patient care units and outpatients' clinics. This original approach from the Pharmacy Department led to the formulation of 35 recommendations to the pharmacy and nursing care committee, which helped to improve the safety of the medication-use system in patient care units and outpatient clinics.
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The emergence of next-generation sequencing (NGS) has revolutionized the way of reaching a genome sequence, with the promise of potentially providing a comprehensive characterization of DNA variations. Nevertheless, detecting somatic mutations is still a difficult problem, in particular when trying to identify low abundance mutations, such as subclonal mutations, tumour-derived alterations in body fluids or somatic mutations from histological normal tissue. The main challenge is to precisely distinguish between sequencing artefacts and true mutations, particularly when the latter are so rare they reach similar abundance levels as artefacts. Here, we present needlestack, a highly sensitive variant caller, which directly learns from the data the level of systematic sequencing errors to accurately call mutations. Needlestack is based on the idea that the sequencing error rate can be dynamically estimated from analysing multiple samples together. We show that the sequencing error rate varies across alterations, illustrating the need to precisely estimate it. We evaluate the performance of needlestack for various types of variations, and we show that needlestack is robust among positions and outperforms existing state-of-the-art method for low abundance mutations. Needlestack, along with its source code is freely available on the GitHub platform: https://github.com/IARCbioinfo/needlestack.
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BACKGROUND: Many different teaching strategies are used to promote learning in an academic or professional environment. Among these can be noted the emergence of simulation, based on the concept of escape games. OBJECTIVE: To identify methodologies relating to the use, design, and implementation of escape games in health care. DATA SOURCES: The Pubmed, Embase, and CINAHL databases were searched up to December 3, 2018. STUDY SELECTION: All studies focusing on the design or development of escape games in the health care field (published in English or French) were included. DATA EXTRACTION: For each study, the country, target population, design, development, method of evaluation, and results were extracted for analysis. DATA SYNTHESIS: Seven poster abstracts and 9 published articles were included. Twelve escape games were developed in the United States. They were used in medicine (n = 5), pharmacy (n = 4), nursing (n = 4) and other fields (n = 3), mainly within academic teaching contexts (n = 12) but also in professional settings (n = 4). Their goals were to improve knowledge (n = 8), to increase participants' interest and motivation regarding a specific topic (n = 2), and to improve cohesion and communication within a team (n = 2). Ten of the escape games described in the articles were based on a clinical scenario. Ten of the research teams held debriefings with participants, and one did not; 5 articles did not report information about debriefing. CONCLUSIONS: Few data exist concerning the use of escape games in the health care setting, and it is too early to judge the efficiency of this approach to learning. However, growing interest justifies systematic monitoring of the literature to follow the evolution of such strategies and to better understand their place in health care education.
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Tobacco smoke contains an extensive cocktail of highly carcinogenic chemicals. Individuals with a slower elimination rate of the chemicals in tobacco smoke may have increased exposure to their carcinogenic properties compared with those with a faster rate. Polymorphisms that alter the function of the genes involved in the activation or the detoxification of the chemical carcinogens in tobacco smoke can potentially influence an individual's risk of developing a tobacco-related cancer. To test this hypothesis, we have genotyped polymorphisms in 16 genes involved in metabolism of chemical carcinogens in a Central and Eastern European case-control study comprising 2,250 lung cases, 811 upper aerodigestive cancer (UADT) cases, and 2,704 controls. The N-acetyltransferase (NAT) genes were the most implicated in risk, with the NAT1*10 haplotype showing an inverse association in lung cancer, in both heterozygote carriers [odds ratio (OR), 0.81; 95% confidence interval (95% CI), 0.70-0.93] and homozygote carriers (OR, 0.70; 95% CI, 0.48-1.01), suggesting a genotype dose response (P < 0.001). In UADT cancer, a similar inverse association was noted in NAT1*10 although only in heterozygotes (OR, 0.78; 95%CI, 0.65-0.95). In NAT2, when considering the individuals inferred acetylator phenotypes based on their NAT2 diplotype, "slow" acetylators compared with intermediate or fast acetylators showed no association with risk. None of the other 14 genes provided robust evidence of an association for either lung or UADT cancer. We therefore conclude that, of the genetic variation studied, NAT1 gene was the most likely candidate to influence the risk of developing a tobacco-related cancer.
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Arilamina N-Acetiltransferase/genética , Neoplasias de Cabeça e Pescoço/epidemiologia , Isoenzimas/genética , Neoplasias Pulmonares/epidemiologia , Polimorfismo Genético/genética , Acetilação , Adenocarcinoma/epidemiologia , Adenocarcinoma/genética , Adenocarcinoma/patologia , Adulto , Idoso , Carcinoma de Células Pequenas/epidemiologia , Carcinoma de Células Pequenas/genética , Carcinoma de Células Pequenas/patologia , Carcinoma de Células Escamosas/epidemiologia , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/patologia , Estudos de Casos e Controles , Europa (Continente)/epidemiologia , Feminino , Genótipo , Neoplasias de Cabeça e Pescoço/genética , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Agências Internacionais , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Fatores de RiscoRESUMO
The DNA repair systems maintain the integrity of the human genome and cell cycle checkpoints are a critical component of the cellular response to DNA damage. We hypothesized that genetic variants in DNA repair and cell cycle control pathways will influence the predisposition to lung cancer, and studied 27 variants in 17 DNA repair enzymes and 10 variants in eight cell cycle control genes in 1,604 lung cancer patients and 2,053 controls. To improve the estimation of risks for specific variants, we applied a Bayesian approach in which we allowed the prior knowledge regarding the evolutionary biology and physicochemical properties of the variant to be incorporated into the hierarchical model. Based on the estimation from the hierarchical modeling, subjects who carried OGG1 326C/326C homozygotes, MGMT 143V or 178R, and CHEK2 157I had an odds ratio of lung cancer equal to 1.45 [95% confidence interval (95% CI), 1.05-2.00], 1.18 (95% CI, 1.01-1.40), and 1.58 (95% CI, 1.14-2.17). The association of CHEK2 157I seems to be overestimated in the conventional analysis. Nevertheless, this association seems to be robust in the hierarchical modeling. None of the pathways seem to have a prominent effect. In general, our study supports the notion that sequence variation may explain at least some of the variation of inherited susceptibility. In particular, further investigation of OGG1, MGMT, and CHEK2 focusing on the genetic regions where the present markers are located or the haplotype blocks tightly linked with these markers might be warranted.
Assuntos
Ciclo Celular/genética , Reparo do DNA/genética , Predisposição Genética para Doença , Neoplasias Pulmonares/genética , Adulto , Idoso , Teorema de Bayes , Biomarcadores Tumorais/genética , Quinase do Ponto de Checagem 2 , DNA Glicosilases/genética , Metilases de Modificação do DNA/genética , Enzimas Reparadoras do DNA/genética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Polimorfismo de Nucleotídeo Único , Proteínas Serina-Treonina Quinases/genética , Fatores de Risco , Fumar/efeitos adversos , Proteínas Supressoras de Tumor/genéticaRESUMO
OBJECTIVES: We have undertaken a comprehensive study of common polymorphisms in genes of DNA repair, exploring both the risk of developing colorectal cancer and the prognosis of patients. METHODS: Subjects from a case-control study (377 cases and 329 controls) designed to assess gene-environment interactions were genotyped by use of an oligonucleotide microarray and the arrayed primer extension technique. Twenty-eight single nucleotide polymorphisms in 15 DNA repair genes were included. The candidate genes belong to different DNA repair pathways: base excision repair (OGG1, LIG3, APEX, POLB, XRCC1, PCNA, and MUTYH), nucleotide excision repair (ERCC1, ERCC2, ERCC4, and ERCC5), double-strand breaks repair (XRCC2, XRCC3, and XRCC9), and reversion repair (MGMT) genes. RESULTS: Polymorphism OGG1 S326C was associated with an increased risk of colorectal cancer [odds ratio (OR), 2.3; 95% confidence interval (95% CI), 1.1-5.0], the risk being higher in younger individuals. A haplotype of ERCC1 was associated with increased risk (OR, 2.3; 95% CI, 1.0-5.3). POLB P242R was also associated with decreased risk (OR, 0.23; 95% CI, 0.05-0.99), although the number of variant allele carriers was low. In the univariate analysis, adjusted for age, sex, and Dukes' stage, three polymorphisms were significantly associated with better prognosis: XRCC1 R399Q [hazard ratio (HR), 0.38; 95% CI, 0.17-0.85], XRCC3 T141M (HR, 0.66; 95% CI, 0.45-0.97), and MGMT L84F (HR, 0.14; 95% CI, 0.02-0.99). ERCC1 19007T>C was associated with worse prognosis (HR, 1.51; 95% CI, 1.01-2.27). In a multivariate analysis, only XRCC1 R399Q and ERCC1 19007T>C remained significant. These associations were stronger among patients receiving adjuvant chemotherapy. CONCLUSIONS: Although the overall effect of DNA repair genes in colorectal cancer etiology seems limited, their influence in the response to chemotherapy and prognosis may be more relevant. This knowledge may help to clarify the utility of specific adjuvant treatments according to the individual genetic background.
Assuntos
Adenocarcinoma/genética , Neoplasias Colorretais/genética , Reparo do DNA , Polimorfismo de Nucleotídeo Único/genética , Adenocarcinoma/diagnóstico , Adenocarcinoma/terapia , Fatores Etários , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/terapia , Seguimentos , Genótipo , Humanos , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Taxa de SobrevidaRESUMO
[This corrects the article DOI: 10.1371/journal.pone.0177775.].
RESUMO
A small proportion of women who are exposed to infection with human-papillomavirus (HPV) develop cervical cancer (CC). Genetic factors may affect the risk of progression from HPV infection to cervical precancer and cancer. We used samples from the International Agency for Research on Cancer (IARC) multicentric case-control study to evaluate the association of selected genetic variants with CC. Overall, 790 CC cases and 717 controls from Algeria, Morocco, India and Thailand were included. Cervical exfoliated cells were obtained from control women and cervical exfoliated cells or biopsy specimens from cases. HPV-positivity was determined using a general primer GP5+/6+ mediated PCR. Unconditional logistic regression was used to estimate odds ratios (OR) and corresponding 95% confidence intervals (CI) of host genotypes with CC risk, using the homozygous wild type genotype as the referent category and adjusting by age and study centre. The association of polymorphisms with the risk of high-risk HPV-positivity among controls was also evaluated. A statistically significant association was observed between single nucleotide polymorphism (SNP) CHR6 rs2844511 and CC risk: the OR for carriers of the GA or GG genotypes was 0.70 (95% CI: 0.43-1.14) and 0.61 (95% CI: 0.38-0.98), respectively, relative to carriers of AA genotype (p-value for trend 0.03). We also observed associations of borderline significance with the TIPARP rs2665390 polymorphism, which was previously found to be associated with ovarian and breast cancer, and with the EXOC1 rs13117307 polymorphism, which has been linked to cervical cancer in a large study in a Chinese population. We confirmed the association between CC and the rs2844511 polymorphism previously identified in a GWAS study in a Swedish population. The major histocompatibility region of chromosome 6, or perhaps other SNPs in linkage disequilibrium, may be involved in CC onset.