Homocysteine and MTHFR and VEGF gene polymorphisms: impact on coronary artery disease

BACKGROUND: Polymorphisms in genes involved in the atherosclerosis development, angiogenesis, and homocysteine (Hcy) metabolism could be risk factors for coronary artery disease (CAD). OBJECTIVE: To evaluate the effect of the VEGF C-2578A and MTHFR C677T polymorphisms on CAD, and the association of these polymorphisms with the severity and extension of atherosclerotic lesions and Hcy concentrations. METHODS: Two hundred and forty-four subjects were evaluated by coronary angiography and included in the study (145 with CAD and 99 controls). The VEGF C-2578A and MTHFR C677T polymorphisms were investigated by the PCR-SSCP and PCR-RFLP techniques, respectively. Plasma Hcy was quantified by liquid chromatography/sequential mass spectrometry (LC-MS/MS). RESULTS: There was no significant difference in allele and genotype distribution between the groups, for both polymorphisms. The univariate analysis showed a higher frequency of the VEGF -2578AA genotype in the group with three-vessel disease (p=0.044). In addition, the VEGF -2578CA genotype was observed more frequently among individuals with <95% stenosis (p=0.010). After adjustment for other risk factors for CAD in a multivariate model, the VEGF C-2578A polymorphism was not found to be an independent correlate of CAD (p=0.688). The MTHFR polymorphism did not show any association with the extension and/or severity of the CAD. The MTHFR C677T polymorphism showed no direct association with hyperhomocysteinemia or increased mean plasma concentrations of Hcy. CONCLUSION: Although there is an apparent association between VEGF C-2578A and the development of coronary atherosclerosis, this association is not independent of conventional cardiovascular risk factors.FUNDAMENTO: Polimorfismos em genes relacionados ao desenvolvimento da aterosclerose, angiogênese e metabolismo da homocisteína (Hcy) podem ser fatores de risco para a doença arterial coronariana (DAC). OBJETIVO: Avaliar o efeito dos polimorfismos VEGF C-2578A e MTHFR C677T na DAC e a associação desses polimorfismos com a gravidade e a extensão das lesões ateroscleróticas e concentrações de Hcy. MÉTODOS: 244 indivíduos foram avaliados através de angiografia coronariana e incluídos no estudo (145 com DAC e 99 indivíduos-controle). Os polimorfismos VEGF C-2578A e MTHFR C677T foram investigados através das técnicas de PCR-SSCP e PCR-RFLP, respectivamente. Os níveis de homocisteína plasmática foram mensurados através de cromatografia líquida/espectrometria de massa seqüencial (CL/EMS). RESULTADOS: Não houve diferença significante em relação à distribuição de alelos e genótipos entre os grupos, para ambos os polimorfismos. A análise univariada mostrou uma freqüência maior do genótipo VEGF -2578AA no grupo com doença em três vasos (p=0,044). Além disso, o genótipo VEGF -2578CA foi observado mais freqüentemente entre indivíduos com <95% de estenose (p=0,010). Após ajuste para outros fatores de risco para DAC em um modelo multivariado, observou-se que o polimorfismo VEGF C-2578A não era um correlato independente da DAC (p=0,688). O polimorfismo MTHFR não mostrou qualquer relação com a extensão e/ou gravidade da DAC. O polimorfismo MTHFR C677T não mostrou uma associação direta com hiperhomocisteinemia ou aumento das concentrações médias de Hcy no plasma. CONCLUSÃO: Embora haja uma aparente associação entre o polimorfismo VEGF C-2578A e o desenvolvimento de aterosclerose coronariana, essa associação não é independente dos fatores de risco cardiovasculares convencionais.FUNDAMENTO: Polimorfismos en genes relacionados al desarrollo de la aterosclerosis, la angiogénesis y el metabolismo de la homocisteína (Hcy) pueden ser factores de riesgo para la enfermedad arterial coronaria (EAC). OBJETIVO: Evaluar el efecto de los polimorfismos VEGF C-2578A y MTHFR C677T en la EAC y la asociación de esos polimorfismos con la severidad y la extensión de las lesiones ateroscleróticas y concentraciones de Hcy. MÉTODOS: Se evaluaron a 244 individuos por medio de angiografía coronaria y se les incluyeron en el estudio (145 con EAC y 99 individuos-control). Los polimorfismos VEGF C-2578A y MTHFR C677T se investigaron mediante las técnicas de PCR-SSCP y PCR-RFLP, respectivamente. Se midieron los niveles de homocisteína plasmática por medio de cromatografía líquida/espectrometría de masa secuencial (CL/EMS). RESULTADOS: No hubo diferencia significante en relación con la distribución de alelos y genotipos entre los grupos, para ambos polimorfismos. El análisis univariado reveló una frecuencia mayor del genotipo VEGF-2578AA en el grupo con enfermedad en tres vasos (P=0,044). Además de ello, se observó el genotipo VEGF-2578CA con más frecuencia entre individuos con <95% de estenosis (p=0,010). Tras ajuste para otros factores de riesgo para EAC en un modelo multivariado, se evidenció que el polimorfismo VEGF C-2578A no era un correlato independiente de la EAC (p=0,688). El polimorfismo MTHFR no mostró cualquier relación con la extensión y/o severidad de la EAC. El polimorfismo MTHFR C677T no evidenció una asociación directa con hiperhomocisteinemia o aumento de las concentraciones promedio de Hcy en el plasma. CONCLUSIÓN: Si bien existe una aparente asociación entre el polimorfismo VEGF C-2578A y el desarrollo de aterosclerosis coronaria, esa asociación no es independiente de los factores de riesgo cardiovasculares convencionales.263268Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq

p53 gene analysis in childhood B non - Hodgkin's lymphoma

CONTEXTO: Alterações do gene supressor de tumor p53, como mutações e deleções, são lesões genéticas encontradas com maior freqüência nas neoplasias humanas, incluindo câncer de mama, pulmão e cólon. Entre as malignidades hematológicas, o gene 53 é freqüentemente mutado no linfoma de Burkitt, sendo detectadas mutações em 30-40% das amostras tumorais e em 70% das linhagens celulares. OBJETIVO: Analisar as alterações do gene p53 em crianças com linfoma não-Hodgkin de origem B. TIPO DE ESTUDO: Estudo descritivo. LOCAL: Centro de Oncologia Terciário. PARTICIPANTES: O estudo analisou 12 pacientes com linfoma não-Hodgkin B classificados como linfoma de Burkitt. A análise de possíveis mutações do gene p53 foi realizada pela técnica de PCR-SSCP dos exons 5, 6 ,7 e 8/9 do gene. RESULTADOS: Um padrão anormal de migração foi observado em quatro pacientes (33.3%), em um paciente no exon 6 e em três no exon 7. Os casos positivos incluíam dois pacientes que evoluíram para o óbito por progressão da doença. CONCLUSÃO: Esses resultados preliminares sugerem que as alterações do gene p53 são freqüentes em crianças com linfoma de Burkitt e podem contribuir para patogênese ou progressão da doença.CONTEXT: Mutations or deletions in the tumor-suppressor gene p53 are among the commonest genetic changes found in human neoplasms including breast, lung and bowel cancers. In hematological malignancies, p53 is most often mutated in Burkitt's lymphoma, with p53 mutations present in 30 to 40% of tumor samples and in 70% of cell lines. OBJECTIVE: To analyze the p53 gene alterations in child patients with B non-Hodgkin's lymphoma. DESIGN: Descriptive study. SETTING: Tertiary oncology care center. PARTICIPANTS: The study investigated 12 patients with childhood B non-Hodgkin's lymphoma (Burkitt's lymphoma). Screening for p53 mutations was done by polymerase chain reaction - single strand conformational polymorphism (PCR-SSCP) analysis of exon 5 to 8/9 of the gene. RESULTS: Abnormal polymerase chain reaction - single strand conformational polymorphism migration pattern was observed in 4 patients (33.3%), one on exon 6 and three on exon 7. Positive cases included 2 patients who died from disease. CONCLUSION: These preliminary results suggest that p53 mutations are quite frequent in children with Burkitt's lymphoma and may play a role in lymphoma genesis or disease progression

p53 gene analysis in childhood B non - Hodgkin's lymphoma

CONTEXT: Mutations or deletions in the tumor-suppressor gene p53 are among the commonest genetic changes found in human neoplasms including breast, lung and bowel cancers. In hematological malignancies, p53 is most often mutated in Burkitt's lymphoma, with p53 mutations present in 30 to 40% of tumor samples and in 70% of cell lines. OBJECTIVE: To analyze the p53 gene alterations in child patients with B non-Hodgkin's lymphoma. DESIGN: Descriptive study. SETTING: Tertiary oncology care center. PARTICIPANTS: The study investigated 12 patients with childhood B non-Hodgkin's lymphoma (Burkitt's lymphoma). Screening for p53 mutations was done by polymerase chain reaction - single strand conformational polymorphism (PCR-SSCP) analysis of exon 5 to 8/9 of the gene. RESULTS: Abnormal polymerase chain reaction - single strand conformational polymorphism migration pattern was observed in 4 patients (33.3%), one on exon 6 and three on exon 7. Positive cases included 2 patients who died from disease. CONCLUSION: These preliminary results suggest that p53 mutations are quite frequent in children with Burkitt's lymphoma and may play a role in lymphoma genesis or disease progression

Homocisteína e polimorfismos dos genes MTHFR e VEGF: impacto na doença arterial coronariana

FUNDAMENTO: Polimorfismos em genes relacionados ao desenvolvimento da aterosclerose, angiogênese e metabolismo da homocisteína (Hcy) podem ser fatores de risco para a doença arterial coronariana (DAC). OBJETIVO: Avaliar o efeito dos polimorfismos VEGF C-2578A e MTHFR C677T na DAC e a associação desses polimorfismos com a gravidade e a extensão das lesões ateroscleróticas e concentrações de Hcy. MÉTODOS: 244 indivíduos foram avaliados através de angiografia coronariana e incluídos no estudo (145 com DAC e 99 indivíduos-controle). Os polimorfismos VEGF C-2578A e MTHFR C677T foram investigados através das técnicas de PCR-SSCP e PCR-RFLP, respectivamente. Os níveis de homocisteína plasmática foram mensurados através de cromatografia líquida/espectrometria de massa seqüencial (CL/EMS). RESULTADOS: Não houve diferença significante em relação à distribuição de alelos e genótipos entre os grupos, para ambos os polimorfismos. A análise univariada mostrou uma freqüência maior do genótipo VEGF -2578AA no grupo com doença em três vasos (p=0,044). Além disso, o genótipo VEGF -2578CA foi observado mais freqüentemente entre indivíduos com <95% de estenose (p=0,010). Após ajuste para outros fatores de risco para DAC em um modelo multivariado, observou-se que o polimorfismo VEGF C-2578A não era um correlato independente da DAC (p=0,688). O polimorfismo MTHFR não mostrou qualquer relação com a extensão e/ou gravidade da DAC. O polimorfismo MTHFR C677T não mostrou uma associação direta com hiperhomocisteinemia ou aumento das concentrações médias de Hcy no plasma. CONCLUSÃO: Embora haja uma aparente associação entre o polimorfismo VEGF C-2578A e o desenvolvimento de aterosclerose coronariana, essa associação não é independente dos fatores de risco cardiovasculares convencionais

Genetic polymorphisms involved in folate metabolism and concentrations of methylmalonic acid and folate on plasma homocysteine and risk of coronary artery disease

Objectives Alterations in the enzymes involved in homocysteine (Hcy) metabolism or vitamin deficiency could play a role in coronary artery disease (CAD) development. This study investigated the influence of MTHFR and MTR gene polymorphisms, plasma folate and MMA on Hcy concentrations and CAD development. MMA and folate concentrations were also investigated according to the polymorphisms. Methods Two hundred and eighty-three unrelated Caucasian individuals undergoing coronary angiography (175 with CAD and 108 non-CAD) were assessed in a case-control study. Plasma Hcy and MMA were measured by liquid chromatography/tandem mass spectrometry. Plasma folate was measured by competitive immunoassay. Dietary intake was evaluated using a nutritional questionnaire. Polymorphisms MTHFR and MTR were investigated by polymerase chain reaction (PCR) followed by enzyme digestion or allele-specific PCR. Results Hcy mean concentrations were higher in CAD patients compared to controls, but below statistical significance (P = 0.246). Increased MMA mean concentrations were frequently observed in the CAD group (P = 0.048). Individuals with MMA concentrations > 0.5 mu mol/l (vitamin B(12) deficiency) were found only in the CAD group (P = 0.004). A positive correlation between MMA and Hcy mean concentrations was observed in both groups, CAD (P = 0.001) and non-CAD (P = 0.020). MMA mean concentrations were significantly higher in patients with hyperhomocysteinemia in both groups, CAD and non-CAD (P = 0.0063 and P = 0.013, respectively). Folate mean concentration was significantly lower in carriers of the wild-type MTHFR 1298AA genotype (P = 0.010). Conclusion Our results suggest a correlation between the MTHFR A1298C polymorphism and plasma folate concentration. Vitamin B(12) deficiency, reflected by increased MMA concentration, is an important risk factor for the development both of hyperhomocysteinemia and CAD.State of Sao Paulo Research Foundation (FAPESP)Coordination for the Improvement of Higher Education (CAPES)National Council for Scientific and Technological Development (CNPq)Fleury Medicine and Healt

Meta-analysis and pooled analysis of GSTM1 and CYP1A1 polymorphisms and oral and pharyngeal cancer: a HuGE-GSEC review

The association of GSTM1 and CYP1A1 polymorphisms and oral and pharyngeal cancers was assessed through a meta-analysis of published case-control studies and a pooled analysis of both published and unpublished case-control studies from the Genetic Susceptibility to Environmental Carcinogens database (http://www.upci.upmc.edu/research/ccps/ccontrol/index.html ). Thirty publications used in the meta-analysis included a total of 7783 subjects (3177 cases and 4606 controls); 21 datasets, 9397 subjects (3130 cases and 6267 controls) were included in the pooled analysis. The GSTM1 deletion was 2-fold more likely to occur in African American and African cases than controls (odds ratio: 1.7, 95% confidence interval: 0.9-3.3), although this was not observed among whites (odds ratio: 1.0, 95% confidence interval: 0.9-1.1). The meta-analysis and pooled analysis showed a significant association between oral and pharyngeal cancer and the CYP1A1 MspI homozygous variant (meta-ORm2/m2: 1.9, 95% confidence interval: 1.4-2.7; Pooled ORm2m2: 2.0, 95% confidence interval: 1.3-3.1; ORm1m2 or [infi]m2m2: 1.3, 95% confidence interval: 1.1-1.6). The association was present for the CYP1A1 (exon 7) polymorphism (ORVal/Val: 2.2, 95% confidence interval: 1.1-4.5) in ever smokers. A joint effect was observed for GSTM1 homozygous deletion and the CYP1A1 m1m2 variant on cancer risk. Our findings suggest that tobacco use and genetic factors play a significant role in oral and pharyngeal cancer