血管内皮生长因子基因3'非翻译区多态性在缺血性脑卒中的作用及其机制研究

摘要

Objective To investigate the relationship between the single nucleotide polymorphisms(SNP) in 3'untranslated region(3'UTR) of vascular endothelial growth factor(VEGF) gene and risk and outcome of ischemic stroke(IS) in Chinese population.Methods A genetic association study of one SNP(rs3025039)in the human VEGF gene was performed in 494 patients with IS and 330 healthy controls by polymerase chain reaction-ligase detection reaction(PCR-LDR) analysis.The assessments of stroke severity on admission and post-stroke disability at 90 days were respectively based on the National Institutes of Health Stroke Severity Scale(NIHSS) and the modified Rankin Scale(mRS).The interaction of miR-199a and VEGF expression was assessed in different rs3025040 genotypes by luciferases reporter assay.Results There was a significant difference in rs3025039 TT genotype frequencies between the IS and the control group (P ＜ 0.05).When divided all IS patients into two groups according to different outcomes,we found VEGF gene rs3025039 TT genotype was associated with the poor recovery in IS patients (P =0.005,OR =1.614,95％ CI 1.158-2.250).Furthermore,we observed a strong linkage disequilibrium (r2 =1.0) between rs3025039 and rs3025040 in VEGF gene 3'UTR region in both normal controls and IS patients.Finally,we found that rs3025040 T allele significantly decreased luciferase activity in ECV-304 cell,which might result in lower VEGF expression levels.Conclusion Our data suggest that the rs3025039 C-＞ T variant may be associated with the susceptibility and it may contribute to a significantly increased risk of having a poorer outcome in stroke,which may be used as an important biomarker for the prediction of IS recovery in Chinese patients.%目的 探讨中国汉族人群血管内皮生长因子(VEGF)基因3'非翻译区(3'UTR)单核苷酸多态性与缺血性卒中(IS)的关系.方法 采用聚合酶链反应-连接酶检测反应(PCR-LDR)对494例IS患者和330例正常对照者的VEGF基因3'UTR区+936C＞T位点(rs3029039)进行基因分型.采用美国国立卫生研究院卒中量表(NIHSS)和改良Rankin量表(mRS)评估患者入院时和治疗后的神经功能缺损程度和恢复情况.采用双荧光报告基因方法检测微小RNA (miR)-199a与SNP位点的交互作用对VEGF基因表达的影响.结果 IS组VEGF基因rs3025039位点TT基因型频率明显高于对照组(P＜0.05).进一步比较IS患者的预后,携带TT基因型的个体发生预后不良的风险是CC基因型患者的1.61倍(P=0.005,OR=1.614,95％ CI1.158 ～2.250).分析rs3025039位点在我国人群中的连锁关系发现,无论在正常人群还是在IS患者中均与另一3'UTR位点+ 1451C＞ T(rs3025040)呈强连锁(r2=1.0).应用双荧光报告基因方法在ECV-304细胞中发现miR-199a可以明显抑制VEGF基因的表达,其中T基因型更为明显.结论 VEGF基因rs3025039位点多态性与中国汉族人群IS易感性有关,且携带TT基因型的IS患者预后更差,可以作为预测中国汉族人群IS预后不良的生物学指标.