RESUMO
BACKGROUND: The metabolism of xenobiotics plays an essential role in smoking related lung function loss and development of Chronic Obstructive Pulmonary Disease. Nuclear Factor Erythroid 2-Like 2 (NFE2L2 or NRF2) and its cytosolic repressor Kelch-like ECH-associated protein-1 (KEAP1) regulate transcription of enzymes involved in cellular detoxification processes and Nfe2l2-deficient mice develop tobacco-induced emphysema. We assessed the impact of Single Nucleotide Polymorphisms (SNPs) in both genes on the level and longitudinal course of Forced Expiratory Volume in 1 second (FEV1) in the general population. METHODS: Five NFE2L2 and three KEAP1 tagging SNPs were genotyped in the population-based Doetinchem cohort (n = 1,152) and the independent Vlagtwedde-Vlaardingen cohort (n = 1,390). On average 3 FEV1 measurements during 3 surveys, respectively 7 FEV1 measurements during 8 surveys were present. Linear Mixed Effect models were used to test cross-sectional and longitudinal genetic effects on repeated FEV1 measurements. RESULTS: In the Vlagtwedde-Vlaardingen cohort SNP rs11085735 in KEAP1 was associated with a higher FEV1 level (p = 0.02 for an additive effect), and SNP rs2364723 in NFE2L2 was associated with a lower FEV1 level (p = 0.06). The associations were even more significant in the pooled cohort analysis. No significant association of KEAP1 or NFE2L2 SNPs with FEV1 decline was observed. CONCLUSION: This is the first genetic study on variations in key antioxidant transcriptional regulators KEAP1 and NFE2L2 and lung function in a general population. It identified 2 SNPs in NFE2L2 and KEAP1 which affect the level of FEV1 in the general population. It additionally shows that NFE2L2 and KEAP1 variations are unlikely to play a role in the longitudinal course of FEV1 in the general population.
Assuntos
Predisposição Genética para Doença/epidemiologia , Predisposição Genética para Doença/genética , Peptídeos e Proteínas de Sinalização Intracelular/genética , Fluxo Expiratório Máximo , Fator 2 Relacionado a NF-E2/genética , Doença Pulmonar Obstrutiva Crônica/epidemiologia , Doença Pulmonar Obstrutiva Crônica/genética , Adulto , Idoso , Estudos de Coortes , Feminino , Genética Populacional/estatística & dados numéricos , Humanos , Incidência , Proteína 1 Associada a ECH Semelhante a Kelch , Masculino , Pessoa de Meia-Idade , Países Baixos/epidemiologia , Polimorfismo de Nucleotídeo Único/genética , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Medição de Risco/métodos , Fatores de RiscoRESUMO
BACKGROUND: Inflammatory bowel disease (IBD), comprising Crohn's disease (CD) and ulcerative colitis (UC), are intestinal inflammatory disorders with a complex genetic background. Mice deficient for the runt-domain-transcription-factor3 (Runx3) develop spontaneous colitis. Human RUNX3 resides in an IBD-susceptibility locus. We studied the association of RUNX3 in a cohort of IBD patients and analyzed the interaction with SLC22A4/5. RUNX3 and OCTN1 mRNA expression was assessed in inflamed and noninflamed mucosa from patients and controls. METHODS: 543 IBD patients (309 CD / 234 UC) and 296 controls were included. Four single nucleotide polymorphisms (SNPs) and 4 microsatellite markers were studied for RUNX3. Five SNPs (including SNP-207G-->C and SNP1672C-->T) were analyzed for SLC22A4/5. RUNX3, and OCTN1 expression in mucosal tissue from 30 patients (14 UC / 16 CD) and 6 controls were determined by quantitative polymerase chain reaction. RESULTS: A significant association between RUNX3-SNP rs2236851 and UC (OR 1.61; 95% confidence interval [CI] 1.11-2.32, P = 0.020) was found. Carriership is associated with pancolitis (odds ratio [OR] 1.86; 95% CI 1.08-3.21). SLC22A4/5-SNPs rs272893 and rs273900 are associated with CD (OR 2.16; 95% CI 1.21-3.59 and OR 2.40; 95% CI 1.43-4.05). We found epistasis for carriership of a risk-associated allele in RUNX3 and SLC22A4/5 for UC patients versus CD patients (OR 3.83; 95% CI 1.26-11.67). RUNX3 mRNA expression is increased (P = 0.01) in inflamed colonic mucosa of UC patients compared to noninflamed mucosa and controls. CONCLUSIONS: We provide evidence for the genetic association of RUNX3 with UC and for CD with the IBD5 locus including SLC22A4/5. An epistatic effect of RUNX3 and SLC22A4 was associated with an increased risk for UC. Our data suggest a role for RUNX3 in UC susceptibility.
Assuntos
Colite Ulcerativa/genética , Subunidade alfa 3 de Fator de Ligação ao Core/genética , Doença de Crohn/genética , Epistasia Genética/genética , Proteínas de Transporte de Cátions Orgânicos/genética , Adolescente , Adulto , Idoso , Estudos de Casos e Controles , Criança , Cromossomos Humanos Par 5 , Colite Ulcerativa/metabolismo , Colite Ulcerativa/patologia , Colo/metabolismo , Colo/patologia , Subunidade alfa 3 de Fator de Ligação ao Core/metabolismo , Doença de Crohn/metabolismo , Doença de Crohn/patologia , Feminino , Predisposição Genética para Doença , Genótipo , Haplótipos , Humanos , Técnicas Imunoenzimáticas , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Masculino , Pessoa de Meia-Idade , Proteína Adaptadora de Sinalização NOD2/genética , Proteínas de Transporte de Cátions Orgânicos/metabolismo , Polimorfismo de Nucleotídeo Único/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Membro 5 da Família 22 de Carreadores de Soluto , Simportadores , Adulto JovemRESUMO
PURPOSE: Response to chemotherapy may be determined by gene polymorphisms involved in metabolism of cytotoxic drugs. A plausible candidate is the gene for bleomycin hydrolase (BLMH), an enzyme that inactivates bleomycin, an essential component of chemotherapy regimens for disseminated testicular germ-cell cancer (TC). We investigated whether the single nucleotide polymorphism (SNP) A1450G of the BLMH gene (rs1050565) is associated with survival. PATIENTS AND METHODS: Data were collected on survival and BLMH genotype of 304 patients with TC treated with bleomycin-containing chemotherapy at the University Medical Center Groningen, the Netherlands, between 1977 and 2003. Survival according to genotype was analyzed using Kaplan-Meier curves with log-rank testing and Cox regression analysis with adjustment for confounders. RESULTS: BLMH gene SNP A1450G has a significant effect on TC-related survival (log-rank P = .001). The homozygous variant (G/G) genotype (n = 31) is associated with decreased TC related survival compared with the heterozygous variant (A/G; n = 133) and the wild-type (A/A; n = 140). With Cox regression the G/G genotype proves to be an unfavorable prognostic factor, in addition to the commonly used International Germ Cell Consensus Classification prognosis group, with a hazard ratio of 4.97 (95% CI, 2.17 to 11.39) for TC-related death. Furthermore, the G/G genotype shows a higher prevalence of early relapses. CONCLUSION: The homozygous variant G/G of BLMH gene SNP A1450G is associated with reduced survival and higher prevalence of early relapses in TC patients treated with bleomycin-containing chemotherapy. This association is hypothesis generating and may eventually be of value for risk classification and selection for alternative treatment strategies in patients with disseminated TC.
Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Bleomicina/administração & dosagem , Cisteína Endopeptidases/genética , Neoplasias Embrionárias de Células Germinativas/tratamento farmacológico , Neoplasias Embrionárias de Células Germinativas/enzimologia , Neoplasias Testiculares/tratamento farmacológico , Neoplasias Testiculares/enzimologia , Adolescente , Adulto , Bleomicina/efeitos adversos , Cisplatino/administração & dosagem , Estudos de Coortes , Etoposídeo/administração & dosagem , Variação Genética , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Embrionárias de Células Germinativas/genética , Neoplasias Embrionárias de Células Germinativas/mortalidade , Farmacogenética , Polimorfismo Genético , Polimorfismo de Nucleotídeo Único , Prognóstico , Fibrose Pulmonar/induzido quimicamente , Análise de Regressão , Taxa de Sobrevida , Neoplasias Testiculares/genética , Neoplasias Testiculares/mortalidadeRESUMO
Hodgkin lymphoma (HL) is characterized by a minority of neoplastic Hodgkin-Reed Sternberg (HRS) cells surrounded by a non-neoplastic reactive infiltrate. As immunological mechanisms appear to be crucial in classical HL pathogenesis, altered serum chemokine levels might be related to disease activity. Serum levels of nine chemokines were examined in 163 untreated HL patients and 334 controls. We investigated single nucleotide polymorphisms (SNPs) for association with serum CCL17 (thymus and activation-regulated chemokine, TARC) levels and HL susceptibility. Serum CCL17 and CCL22 (macrophage-derived chemokine, MDC) levels were significantly increased in 82% and 57% of the HL patients. Nodular sclerosis cases showed increased serum CCL17 and CCL22 levels (P < 0.001) and serum levels were correlated with Ann Arbor stage. Of nine patients with pre- and post-treatment serum samples, the majority showed decreased CCL17 and CCL22 levels after treatment. HRS cells expressed CCL17 and CCL22 in 77% and 75% of 74 cases. Three SNPs showed a trend of increased serum CCL17 levels with minor alleles in controls, but were not associated with HL susceptibility. CCL17 and CCL22 were the only chemokines with increased serum levels in the vast majority of HL patients, which provides further insight into the molecular mechanism(s) leading to infiltrations of reactive lymphocytes in HL.
Assuntos
Quimiocina CCL17/sangue , Quimiocina CCL22/sangue , Doença de Hodgkin/sangue , Proteínas de Neoplasias/sangue , Quimiocinas/sangue , Predisposição Genética para Doença , Genótipo , Doença de Hodgkin/genética , Doença de Hodgkin/patologia , Humanos , Estadiamento de Neoplasias , Polimorfismo de Nucleotídeo ÚnicoRESUMO
OBJECTIVES: The effect of glucocorticoid substitution on the prevalence of metabolic syndrome components (NCEP ATP III criteria) and serum lipid levels was determined in GH-replaced hypopituitary patients. As glucocorticoid replacement is associated with a pronounced decrease in plasma cholesteryl ester transfer protein (CETP) activity, we also tested associations of HDL cholesterol with the -629C>A CETP promoter polymorphism in subjects with and without ACTH deficiency. DESIGN AND PATIENTS: In a university setting, we retrieved protocolized clinical and laboratory data from 165 adult hypopituitary patients, who had received GH for 1 year. RESULTS: After adjustment for age, sex and smoking, non-HDL cholesterol (P = 0.05) and triglycerides (P = 0.004) were higher, but HDL cholesterol was not decreased in 117 glucocorticoid (mainly cortisone acetate in two divided doses) receiving subjects compared to 48 ACTH-sufficient subjects. The prevalence of elevated plasma glucose and/or diabetes (P = 0.04) and hypertriglyceridaemia (P = 0.005), but not of other metabolic syndrome components, was higher in glucocorticoid-replaced subjects. HDL cholesterol was higher in -629 A allele carriers compared to -629CC homozygotes in ACTH-sufficient subjects (P = 0.04), but not in glucocorticoid-treated subjects (P = 0.13). Multiple linear regression analysis demonstrated that only in ACTH-sufficient subjects, HDL cholesterol was independently related to this CETP gene variation (P = 0.03). CONCLUSIONS: In GH- and glucocorticoid-replaced hypopituitary patients, serum non-HDL cholesterol and triglycerides are higher and the prevalence of hyperglycaemia is increased, but HDL cholesterol is not decreased. Conventional glucocorticoid replacement appears to diminish the association of HDL cholesterol with a common CETP gene variation.
Assuntos
Glicemia/metabolismo , Proteínas de Transferência de Ésteres de Colesterol/genética , Colesterol/sangue , Glucocorticoides/efeitos adversos , Hormônio do Crescimento Humano/uso terapêutico , Hipertrigliceridemia/induzido quimicamente , Hipopituitarismo/tratamento farmacológico , Polimorfismo de Nucleotídeo Único , Adolescente , Adulto , Idoso , Glicemia/efeitos dos fármacos , Proteínas de Transferência de Ésteres de Colesterol/fisiologia , Feminino , Ligação Genética , Glucocorticoides/uso terapêutico , Terapia de Reposição Hormonal/efeitos adversos , Humanos , Hipertrigliceridemia/sangue , Hipertrigliceridemia/epidemiologia , Hipopituitarismo/sangue , Hipopituitarismo/genética , Masculino , Síndrome Metabólica/induzido quimicamente , Síndrome Metabólica/epidemiologia , Pessoa de Meia-Idade , Prevalência , Regiões Promotoras Genéticas , Adulto JovemRESUMO
OBJECTIVE: Inflammatory bowel diseases (IBD) have a complex genetic background. The interleukin receptor associated kinase-M (IRAK-M) is a NF-kappaB-mediated, negative regulator of Toll-like receptor (TLR) signaling. A functional mutation in a negative regulator might induce impaired endotoxin tolerance and increased inflammatory responses. IRAK-M is situated on chromosome 12q14, a susceptibility locus for IBD, which makes it a good candidate gene. The objective of the study was to analyze a large cohort of IBD patients for the association between IBD and IRAK-M. MATERIAL AND METHODS: A total of 542 patients with IBD (309 Crohn's disease (CD), 233 ulcerative colitis (UC)) and 305 controls were studied. Two single nucleotide polymorphisms (V147I and V270I) and six microsatellite markers were evaluated using association analysis and the haplotype sharing statistic. Results were stratified for CARD15 mutations R702W, G908R and 1007fsinsC. RESULTS: No significant differences in IRAK-M allele frequencies were observed between IBD, UC, CD or subgroups of CD or UC and controls. Five out of 36 UC patients (13.9%) with an IBD-associated CARD15 mutation were carriers versus 2/167 (1.2%) in non-carriers (OR 13.1, 95% CI 1.0-164.5). No interaction was observed for CD. CONCLUSIONS: No evidence was found to suggest an association between IBD, CD, UC or subsets of CD and UC and IRAK-M. However, an interaction was found between IRAK-M and CARD15 in UC patients. In CARD15 mutant patients, the production of IRAK-M upon stimulation might be impaired. Further studies are needed to determine whether an impaired negative regulation of the TLR-signaling pathway might be partly responsible for the development of IBD.
Assuntos
Colite Ulcerativa/genética , Doença de Crohn/genética , Frequência do Gene , Predisposição Genética para Doença , Quinases Associadas a Receptores de Interleucina-1/genética , Proteína Adaptadora de Sinalização NOD2/genética , Adolescente , Adulto , Idoso , Criança , Cromossomos Humanos Par 12 , Estudos de Coortes , Feminino , Humanos , Desequilíbrio de Ligação , Masculino , Repetições de Microssatélites , Pessoa de Meia-Idade , Mutação , Países Baixos , Reação em Cadeia da Polimerase , Polimorfismo de Nucleotídeo ÚnicoRESUMO
BACKGROUND: Genetic susceptibility may play a more important role in the etiology of early-onset inflammatory bowel disease (IBD) than in late-onset IBD, and therefore pediatric-onset IBD patients can be expected to have a higher frequency of gene mutations. We aimed to determine genotypes and phenotypes of patients with pediatric-onset IBD, to compare them with those of patients with adult-onset IBD and with controls, and to identify genotype-phenotype associations. METHODS: Polymorphisms R702W, G908R, and 3020insC of CARD15 (caspase activating recruitment domain 15); Asp299Gly and Thr399Ile of TLR4; -207G-->C, 1672C-->T (L503F), rs3792876, rs274551, rs272893, and rs273900 of SLC22A4/5; and 113G-->A as well as rs2289311, rs1270912, and rs2165047 of DLG5 (Drosophila discs large homologue 5) were assessed in 103 pediatric-onset and 696 adult-onset IBD patients. Phenotypic classification was based on disease localization and behavior. RESULTS: Homozygosity for 3020insC in CARD15 was significantly higher in patients with pediatric-onset Crohn's disease (CD) than in patients with adult-onset CD (4.2% versus 0.6%, 95% confidence interval [CI] 1.2-42.0). Homozygosity for single-nucleotide polymorphism (SNP) rs3792876 in SLC22A4/5 was significantly higher in patients with pediatric-onset CD than in patients with adult-onset CD (6.1% versus 1.1%, P=0.02). Polymorphism 3020insC in CARD15 was associated with ileal involvement (1.9% versus 13.3%, CI 1.0-53.8) and a positive family history (6.1% versus 20%, CI 1.2-9.0). DLG5 SNP rs2165047 was significantly associated with perianal disease (50% versus 21.2%, CI 1.4-4). CONCLUSIONS: Polymorphisms 3020insC in CARD15 and SNP rs3792876 in SLC22A4/5 occurred statistically significantly more often in patients with pediatric-onset CD than in patients with adult-onset CD. Polymorphisms 3020insC in CARD15 and SNP rs2165047 in DLG5 were associated with specific phenotypes in this pediatric-onset CD cohort.
Assuntos
Idade de Início , Doença de Crohn/genética , Predisposição Genética para Doença , Proteínas de Membrana/genética , Proteína Adaptadora de Sinalização NOD2/genética , Proteínas Supressoras de Tumor/genética , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Estudos de Coortes , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Polimorfismo Genético , Polimorfismo de Nucleotídeo ÚnicoRESUMO
Various studies have indicated that the human leukocyte antigen (HLA) region is associated with Hodgkin's lymphoma. We recently showed a specific association of the HLA class I region with EBV-positive Hodgkin's lymphoma cases. One haplotype of two consecutive microsatellite markers (D6S265 and D6S510) was overrepresented in the patient group, whereas another haplotype was underrepresented. Here, we did fine mapping of this region of approximately 400 kb as a next step to find the causative single-nucleotide polymorphism(s) (SNP). To select candidate SNPs for screening the total study population, several known SNPs were determined by sequencing two individuals homozygous for either of the above-mentioned associated haplotypes. Seven SNPs displayed different alleles in these two individuals and were therefore analyzed in the total study population, including 238 Hodgkin's lymphoma patients and 365 family-based controls. All seven SNPs showed significant association with the EBV-positive patient group. Two of these SNPs were analyzed in a Scottish Hodgkin's lymphoma population and revealed significant associations as well. The associated SNPs are located nearby two putative candidate genes: HLA-A and HLA complex group 9. HLA-A represents the most interesting target because of its consistent expression in EBV-positive Hodgkin's lymphoma cases and its ability to present EBV-derived peptides to cytotoxic T cells.
Assuntos
Mapeamento Cromossômico , Genes MHC Classe I , Antígenos HLA-A/genética , Herpesvirus Humano 4/metabolismo , Doença de Hodgkin/genética , Doença de Hodgkin/imunologia , Doença de Hodgkin/virologia , Polimorfismo de Nucleotídeo Único , Alelos , Estudos de Casos e Controles , Haplótipos , Homozigoto , Humanos , Linfoma/metabolismo , Países Baixos , Peptídeos/química , Linfócitos T Citotóxicos/imunologiaRESUMO
OBJECTIVE: The multidrug resistance (MDR1) gene encodes for P-glycoprotein, a drug efflux pump. Mice deficient for the MDR1a gene spontaneously develop colitis. In humans, a polymorphism in exon 26 (C3435T) is associated with reduced expression levels and function of MDR1. Currently there are controversial data on the association between MDR1 and inflammatory bowel disease (IBD). The purpose of this study was to examine the involvement of this gene in IBD in a large population of Dutch patients with IBD and family-based controls. MATERIAL AND METHODS: A total of 781 IBD cases and 315 controls were investigated. CD phenotypes were determined according to the Vienna Classification. Individuals were genotyped for six single nucleotide polymorphisms (SNPs) close to and in the MDR1 locus. This included the C3435T variant and six microsatellite markers close to and in the MDR1 locus. Single locus association analysis, haplotype association analysis and haplotype sharing statistic (HSS) were used to search for differences between patients and controls. RESULTS: No association was observed for any of the SNPs with IBD as a group, or for ulcerative colitis, Crohn's disease and Crohn's disease phenotypes, either by single locus or haplotype association analysis or by HSS. CONCLUSIONS: No association was observed between the MDR1 gene and IBD. This suggests that it is unlikely that MDR1 plays a role in IBD susceptibility.
Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Resistência a Múltiplos Medicamentos/genética , Doenças Inflamatórias Intestinais/genética , Adulto , Colite Ulcerativa/genética , Doença de Crohn/genética , Feminino , Genótipo , Humanos , Masculino , Repetições de Microssatélites , Fenótipo , Polimorfismo de Nucleotídeo ÚnicoRESUMO
BACKGROUND: A common polymorphism positioned at +405 of the vascular endothelial growth factor (VEGF) gene is known to influence VEGF protein production. In contrast, a second polymorphism, positioned at -460 polymorphism, has no reported functional effects. VEGF is linked to angiogenesis and might directly influence the clinical outcome of patients with chronic heart failure (CHF). We investigated the association between two VEGF polymorphisms and morbidity and mortality in patients with CHF. METHODS AND RESULTS: VEGF promoter polymorphisms +405 and -460 were examined in 596 CHF patients enrolled in the Metoprolol CR/XL Randomized Intervention Trial in Heart Failure (MERIT-HF) study and in 187 healthy controls. In CHF patients, a risk ratio for each genotype was calculated using the combined endpoint of all-cause mortality or hospitalization. The allele frequencies of the +405 and -460 polymorphisms for the CHF cohort and for 187 healthy controls were not significantly different. However, the presence of the +405 CC genotype (frequency 0.14) was independently associated with an adverse outcome as described by the MERIT study combined endpoint compared with the +405 GG genotype (risk ratio 1.65; 95%CI 1.03-2.64; P = .039). The -460 polymorphism was not associated with an altered prognosis ( P = .60). CONCLUSION: Our results indicate that the VEGF +405 CC genotype is associated with an adverse clinical outcome in patients with CHF. This genotype has been associated with lower plasma VEGF levels, suggesting a possible mechanism of action for the gene variant. This belief is further supported by the fact that the VEGF -460 polymorphism, which does not affect plasma VEGF levels, did not adversely affect the prognosis.
Assuntos
Citosina , Insuficiência Cardíaca/genética , Polimorfismo Genético/genética , Regiões Promotoras Genéticas/genética , Fator A de Crescimento do Endotélio Vascular/genética , Antagonistas Adrenérgicos beta/uso terapêutico , Estudos de Casos e Controles , Estudos de Coortes , Feminino , Seguimentos , Frequência do Gene/genética , Genótipo , Guanina , Insuficiência Cardíaca/tratamento farmacológico , Insuficiência Cardíaca/fisiopatologia , Hospitalização , Humanos , Masculino , Metoprolol/uso terapêutico , Pessoa de Meia-Idade , Neovascularização Patológica/genética , Placebos , Taxa de Sobrevida , Timina , Resultado do Tratamento , Fator A de Crescimento do Endotélio Vascular/sangueRESUMO
The CHEK2 1100delC mutation was recently identified as a low-penetrance breast cancer susceptibility allele. The mutation occurred more frequently in families with clustering of breast and colorectal cancers (CRCs) than in families with clustering of breast cancer only. Hence, the 1100delC mutation could also be a low-penetrance CRC susceptibility allele. To test this hypothesis, we examined the mutation in 629 unselected CRC cases, 230 controls, and 105 selected CRCs diagnosed in patients before age 50. The mutation was observed in 1.6% of unselected patients and in 0.3% of controls (Not significant (NS)). After stratifying unselected patients according to defined genetic risk (on the basis of age at diagnosis and family history of colorectal and endometrial cancer), the highest frequency was observed in high-risk patients (12.5%), followed by moderate-risk patients (3.3%), and was lowest in low-risk patients (1.0%, P(trend) 0.014). In selected patients, 1.6% carried the mutation (NS). Subgroup analyses for tumor localization, gender, and age at diagnosis did not reveal an association with the 1100delC genotype. In addition, a pooled analysis, combining data of one published study in unselected CRC cases and our study, also did not reveal an association. In conclusion, the frequency of the 1100delC genotype was neither significantly increased in unselected CRC patients nor in selected CRC patients diagnosed before age 50. However, after stratifying unselected CRC patients according to defined genetic risk, a significant trend of increasing frequency was observed. Together, the results are consistent with a low-penetrance effect (OR 1.5-2.0) of the CHEK2 1100delC on CRC risk. Large case-control studies are required to clarify the exact role of the CHEK2 1100delC mutation in CRC.
Assuntos
Neoplasias Colorretais/genética , Proteínas Serina-Treonina Quinases/genética , Quinase do Ponto de Checagem 2 , Feminino , Frequência do Gene , Predisposição Genética para Doença , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , RiscoRESUMO
PURPOSE: Recently, we found a certain haplotype in the human leukocyte antigen Class III subregion to be associated with breast cancer. Epidemiologic studies have shown that breast cancer and colorectal cancer have several risk factors in common. In view of these studies and because polymorphisms located in the human leukocyte antigen III region have been found to be associated with colorectal cancer, we wondered whether the same region also is involved in colorectal cancer susceptibility. METHODS: The human leukocyte antigen region was genotyped with 14 microsatellite markers in germline DNA from 643 colorectal cancer patients and 841 family-based controls. Association analyses and the Haplotype Sharing Statistic were used to search for differences between patients and controls. Subgroup analyses were performed for gender, age at diagnosis, and localization of the tumor. RESULTS: The Haplotype Sharing Statistic analysis revealed neither a difference in mean haplotype sharing between all patients and controls, nor in any of the subgroups. The single allele, genotype, and two-locus association analyses for all patients and for the different subgroups did not show an association with colorectal cancer for the 14 microsatellite markers. Also, no association was observed between the tumor necrosis factor-beta polymorphism and colorectal cancer. CONCLUSIONS: No association was observed between commonly occurring haplotypes and alleles in the human leukocyte antigen region and colorectal cancer risk.
Assuntos
Neoplasias Colorretais/genética , Antígenos HLA/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Alelos , Estudos de Casos e Controles , Feminino , Marcadores Genéticos , Predisposição Genética para Doença , Genótipo , Haplótipos , Humanos , Desequilíbrio de Ligação , Masculino , Repetições de Microssatélites , Pessoa de Meia-Idade , Países Baixos , Sistema de Registros , Fatores de RiscoRESUMO
Methylenetetrahydrofolate reductase (MTHFR) is a critical enzyme regulating the metabolism of folate and methionine. The potential influence of MTHFR activity on DNA methylation and on the availability of uridylates and thymidylates for DNA synthesis and repair presents MTHFR as a candidate for being a cancer-predisposing gene. In the present study, we have examined a large study population to determine whether the C677T polymorphism at the MTHFR locus affects susceptibility for cervical cancer or its precursor, cervical intraepithelial neoplasia (CIN). In addition, we have investigated whether this polymorphism is causal, and not merely associated, by typing microsatellite markers in the region surrounding the MTHFR gene. A total of 311 CIN and 695 cervical cancer patients and 115 family-based and 586 unrelated controls was analysed. Association analysis showed a decreased cervical cancer risk for individuals heterozygous or homozygous for the T-allele, both for squamous cell carcinoma (heterozygous odds ration [OR] 0.66 [0.51-0.86]; homozygous OR 0.76 [0.49-1.16]) and adenocarcinoma (heterozygous OR 0.71 [0.49-1.03]; homozygous OR 0.34 [0.14-0.81]). No difference was found for high grade CIN (heterozygous OR 1.03 [0.76-1.40]; homozygous OR 0.91 [0.54-1.55]). A microsatellite haplotype containing the C allele was associated with an increased risk for cervical cancer and CIN (both among squamous cell carcinomas, adenocarcinomas and CIN II-III; OR = 2.61 [1.59-4.27]). Our study thus lends further support to the hypothesis that the MTHFR C677T polymorphism is involved in susceptibility cervical cancer but also illustrates that, despite the large sample size analysed, still larger studies are needed to establish fully the nature of this association.
Assuntos
Predisposição Genética para Doença , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Lesões Pré-Cancerosas/genética , Neoplasias do Colo do Útero/genética , Sequência de Bases , Estudos de Casos e Controles , Primers do DNA , Feminino , HumanosRESUMO
BRCA1 and BRCA2 germline mutations account for <5% of breast cancer cases. Less penetrant breast cancer susceptibility genes are likely to exist. Earlier studies have suggested involvement of the HLA region. The HLA region was genotyped with 24 microsatellite markers and markers for two single nucleotide polymorphisms (SNPs) in TNFalpha and TNFbeta, in germline DNA from 956 breast cancer patients and 1271 family-based controls. Association analyses and the haplotype sharing statistic (HSS) were used to search for differences in haplotype sharing between patients and controls. Based on criteria known to influence genetic breast cancer risk, patients were divided into groups of high, moderate and low risk. The HSS revealed a significant difference in mean haplotype sharing between patients and controls for four consecutive markers (D6S2671, TNFa, D6S2672 and MICA), the highest being at D6S2671 (P=0.017). Subgroup analyses showed that moderate-risk patients were responsible for this difference, with the strongest association for D6S2672 (P=0.0009). A single haplotype was more frequent and longer in moderate-risk patients than in controls. The results were confirmed with association analyses. Individuals homozygous for haplotype 110-184 (D6S2672-MICA) were observed in 9.0% of moderate-risk patients and 1.5% of controls [odds ratio (OR)=7.14], while heterozygotes were at a lower risk (OR=1.41), suggesting a recessive effect. No association was observed between the two SNPs in TNFalpha (-308) and TNFbeta (intron 1) and breast cancer risk. The results reveal a potential role of the HLA class III subregion in susceptibility to breast cancer in patients at moderate familial risk.