RESUMO
OBJECTIVE: The aim of this study was to confirm previous reports in order to substantiate the hypothesis that functional variants of two genes, namely methylenetetrahydrofolate reductase and angiotensin I converting enzyme, both involved in an important pathway of migraine, increase migraine susceptibility when present in combination. BACKGROUND: Migraine is a complex genetic disease. The migraine attack is thought to be the result of an interaction of neuronal and vascular events, possibly originating in the brainstem leading to activation of the pain processing trigeminovascular system. Functional variants in the methylenetetrahydrofolate gene and the angiotensin I converting enzyme have influence on vascular mechanism and have been investigated intensively in migraine. The published results were inconsistent; however, both polymorphisms in combination have been shown to increase migraine susceptibility. METHODS: In this genetic association study, the prevalence of the functionally relevant polymorphisms C677T in the MTHFR gene and I/D polymorphism in the ACE gene was compared in 420 patients with migraine vs 258 migraine-free controls using a chi-square statistic and binary logistic regression. RESULTS: Susceptibility to any type of migraine (migraine with aura, migraine without aura, and both types combined) was neither increased by each polymorphism on its own, nor in combination (MTHFR: X(2) = 0.18 [P = .91]; ACE: X(2) = 1.62 [P = .45]; combined: OR = 1.02 [95% CI 0.98-1.05] P = .97). CONCLUSIONS: We could not replicate a previous study that showed significant increase in migraine susceptibility for two functional polymorphisms in genes affecting relevant pathways.
Assuntos
Predisposição Genética para Doença , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Enxaqueca com Aura/genética , Enxaqueca sem Aura/genética , Peptidil Dipeptidase A/genética , Polimorfismo de Nucleotídeo Único , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Estudos Transversais , Feminino , Frequência do Gene , Estudos de Associação Genética , Técnicas de Genotipagem , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Enxaqueca com Aura/epidemiologia , Enxaqueca sem Aura/epidemiologia , Prevalência , Adulto JovemRESUMO
Post-transplantation lymphoproliferative disorders (PTLD) arise in the immunosuppressed and are frequently Epstein-Barr virus (EBV) associated. The most common PTLD histological sub-type is diffuse large B-cell lymphoma (EBV+DLBCL-PTLD). Restoration of EBV-specific T-cell immunity can induce EBV+DLBCL-PTLD regression. The most frequent B-cell lymphoma in the immunocompetent is also DLBCL. 'EBV-positive DLBCL of the elderly' (EBV+DLBCL) is a rare but well-recognized DLBCL entity that occurs in the overtly immunocompetent, that has an adverse outcome relative to EBV-negative DLBCL. Unlike PTLD (which is classified as viral latency III), literature suggests EBV+DLBCL is typically latency II, i.e. expression is limited to the immuno-subdominant EBNA1, LMP1 and LMP2 EBV-proteins. If correct, this would be a major impediment for T-cell immunotherapeutic strategies. Unexpectedly we observed EBV+DLBCL-PTLD and EBV+DLBCL both shared features consistent with type III EBV-latency, including expression of the immuno-dominant EBNA3A protein. Extensive analysis showed frequent polymorphisms in EB-NA1 and LMP1 functionally defined CD8+ T-cell epitope encoding regions, whereas EBNA3A polymorphisms were very rare making this an attractive immunotherapy target. As with EBV+DLBCL-PTLD, the antigen presenting machinery within lymphomatous nodes was intact. EBV+DLBCL express EBNA3A suggesting it is amenable to immunotherapeutic strategies.
