The association between vascular endothelial growth factor gene polymorphisms and stroke: a meta-analysis

A meta-analysis on associations of IL-6 and IL-10 polymorphisms with susceptibility to ischemic stroke

BACKGROUND

Some previous studies already explored associations of interleukin-6 (IL-6) and interleukin-10 (IL-10) polymorphisms with ischemic stroke (IS). However, the results were conflicting. In this meta-analysis, we aimed to better analyze the relationship between IL-6/IL-10 polymorphisms and IS in a larger pooled population.

METHODS

We performed a systematic search of PubMed, Web of Science, Embase and CNKI. We calculated pooled odds ratios (ORs) and 95% confidence intervals (CIs) to estimate associations between IL-6/IL-10 polymorphisms and IS.

RESULTS

Totally 37 studies were included for analyses. A significant association with IS was observed for IL-10 rs1800896 polymorphism in AA versus GG + GA (recessive model, p = .001, OR = 1.42, 95%CI 1.15-1.75) in overall population. Further subgroup analyses showed that IL-6 rs1800795 was significantly associated with IS in Asians in GG versus GC + CC (dominant model, p = .0005, OR = 0.74, 95%CI 0.62-0.88), CC versus GG + GC (recessive model, p = .003, OR = 1.61, 95%CI 1.17-2.21) and G versus C (allele model, p = .01, OR = 0.74, 95%CI 0.58-0.93), whereas IL-10 rs1800896 polymorphism was significantly associated with cerebral infarction (CI) in GG versus GA + AA (dominant model, p = .02, OR = 2.04, 95%CI 1.14-3.64), GA versus GG + AA (overdominant model, p = .03, OR = 0.50, 95%CI 0.27-0.93) and G versus A (allele model, p = .01, OR = 1.92, 95%CI 1.16-3.17).

CONCLUSIONS

Our findings indicated that IL-6 rs1800795 polymorphism was significantly associated with individual susceptibility to IS in Asians, but not in Caucasians. In addition, IL-10 rs1800896 polymorphism was also significantly associated with individual susceptibility to IS, especially for CI.

Association of 18bp insertion/deletion polymorphism, at -2549 position of VEGF gene, with diabetic vascular complications in type 2 diabetes mellitus

PURPOSE

Diabetes mellitus type 2 (T2DM) and its vascular complications are a serious world health problem. For this reason it is important to look for new diabetes complication risk factors. The aim of this study was to determine whether 18-bp insertion/deletion (I/D) polymorphism at -2549 position of the vascular endothelial growth factor (VEGF) gene is associated with diabetic vascular complications (DVC).

MATERIAL AND METHODS

Caucasian subjects (n = 100) with T2DM were recruited for this study. Genotyping of the VEGF gene I/D polymorphism was done by the polymerase chain reaction (PCR) method. The results were correlated with laboratory and clinical data.

RESULTS

In our population heterozygous of the VEGF gene polymorphism was observed most frequently (57%). DVC were observed in 53 patients. Heterozygous T2DM patients significantly more often suffered from heart failure (HF) and stroke (p = 0.05). Amongst all the DVC, D allele of the VEGF polymorphism had a significantly increased risk of diabetic retinopathy (DR) (OR = 1.31; p = 0.033) irrespective of the duration of diabetes, BMI, the glycemia control expressed by HbA1c, renal function, lipid values or applied treatment. The studied polymorphism did not correlate with coronary heart disease, peripheral vascular disease, cardiovascular death, diabetic kidney disease or applied treatment.

CONCLUSIONS

The multivariate logistic regression analysis showed that the D allele in the promoter region of the VEGF gene is an independent risk factor of DR irrespective of other laboratory and clinical variables in T2DM patients. Our study suggests that I/D allele in the studied gene is associated with HF and strokes.

The association between vascular endothelial growth factor gene polymorphisms and stroke: A PRISMA-compliant meta-analysis

BACKGROUND

Numerous studies showed that vascular endothelial growth factor (VEGF) gene polymorphisms were linked with the regularity of stroke, but the results remained controversial. The aim of this meta-analysis was to determine the associations between VEGF gene polymorphisms and the risk of stroke.

METHODS

A systematic literature search of PubMed, Embase, Wed of Science, The Cochrane Library, Elsevier, China National Knowledge Infrastructure, China Biology Medicine disc, WanFang Data, VIP Database for Chinese Technical Periodicals, and Science paper Online was conducted. Two authors independently assessed trial quality and extracted data. The pooled odds ratio (OR) with 95% confidence interval (CI) was used to assess the strength of associations. Begger funnel plot and Egger test were used to estimate the publication bias of included studies. Heterogeneity assumption was assessed by Cochran Chi-squared-based Q-statistic test and I test.

RESULTS

Thirteen publications including 23 trails with a total of 3794 stroke patients and 3094 control subjects were enrolled. About 3747 cases and 2868 controls for +936C/T, 2134 cases and 1424 controls for -2578C/A, and 2187 cases and 1650 controls for -1154G/A were examined, respectively. The results indicated that VEGF +936C/T (T vs C, OR = 1.19, 95% CI = 1.01-1.40) or -2578C/A (A vs C, OR = 1.13, 95% CI = 1.02-1.27) was positively associated with the risk of stroke, whereas there was no association between -1154G/A (A vs G, OR = 0.99, 95% CI = 0.87-1.11) polymorphism and stroke risk in our study. Among the subgroup analyses on ethnicity, the results showed that VEGF +936C/T was an increased risk of stroke in Asian population (T vs C, OR = 1.21, 95% CI = 1.01-1.44), but not -1154G/A.

CONCLUSION

Our findings suggest that VEGF +936C/T and -2578C/A might be related to the risk of stroke, especially in the Asian population, but not -1154G/A.

KRAS and VEGF gene 3'-UTR single nucleotide polymorphisms predicted susceptibility in colorectal cancer

Single nucleotide polymorphisms (SNPs) in tumor-related genes have been reported to play important roles in cancer development. Recent studies have shown that 3’-untranslated regions (UTR) polymorphisms are associated with the occurrence and prognosis of cancers. The aim of this study is to analyze the association between KRAS and VEGF gene 3’-UTR SNPs and genetic susceptibility to colorectal cancer (CRC). In this case-control study of 371 CRC cases and 246 healthy controls, we analyzed the association between one SNP (rs1137188G > A) in the KRAS gene and four SNPs (rs3025039C > T, rs3025040C > T, rs3025053G > A and rs10434A > G) in the VEGF gene and CRC susceptibility by the improved multiplex ligase detection reaction (iMLDR) method. We checked the selected SNPs’ minor allele frequency and its distribution in the frequency of Chinese people by Hap-map database and Hardy-Weinberg equilibrium, and used multivariate logistic regression models to estimate adjusted odds ratios (AORs) and 95% confidence intervals (95% CIs). We found that the rs3025039C variant genotype in the VEGF gene was associated with a significant protection for CRC (AOR = 0.693, 95% CI = 0.485–0.989; P = 0.043 for CC and CT+TT). Nevertheless, the difference was no longer significant after Bonferroni correction (Bonferroni-adjusted P = 0.172). In genetic polymorphisms analysis, we found that the KRAS rs1137188 variant AA genotype had higher portion of tumor size (≥ 5 cm) (P = 0.01; Bonferroni-adjusted P = 0.04), which suggested that the rs1137188 variant AA genotype may significantly be associated with increased progression of CRC. In conclusion, our study suggested that these five SNPs in the KRAS gene and the VEGF gene were not associated with CRC susceptibility in Han Chinese in Sichuan province.

A functional variant in the 3'-UTR of VEGF predicts the 90-day outcome of ischemic stroke in Chinese patients

Vascular endothelial growth factor (VEGF) plays critical roles in angiogenesis and vasculogenesis, which are associated with post-stroke functional recovery. However, the effects of the VEGFA polymorphisms on the outcome of ischemic stroke (IS) have been rarely reported. We therefore investigated the associations of +936C/T variant (rs3025039) with the susceptibilities and the 90-day outcomes from 494 IS patients and 337 healthy controls in Chinese population through the establishment of logistic multivariate regression model. Stroke severity at admission and outcome of 90 days were respectively assessed according to the National Institutes of Health Stroke Scale and the modified Rankin Scale. The analysis showed that there were no significant associations of the rs3025039 genotypes with the susceptibility (P = 0.229) and the severity (P = 0.734). However, when we divided the 308 IS patients into two groups according to the different outcomes, we found that the rs3025039 TC+TT genotype significantly increased the risk of poor recovery [adjusted odds ratio (OR), 1.99; 95% confidence interval (CI), 1.18–3.37]. Interestingly, we observed another 3ˈUTR variant, +1451C/T (rs3025040), exhibited strong linkage disequilibrium (r² = 1.0) with +936C/T and was located in a predicted microRNA-binding site. The rs3025040 T allele significantly decreased the luciferase activities in four cell lines, which indicated a potential disruption of the miRNA-mRNA interaction that would result in lower VEGF expression levels. Our data suggested that the +936C/T variants significantly increased the risk of poorer stroke outcome by affecting the bindings of miR-199a and miR-199b to VEGF mRNA at the rs30250340 polymorphic site.

The association between vascular endothelial growth factor gene polymorphisms and stroke: a meta-analysis

OBJECTIVES

Numerous studies have investigated the relationships between vascular endothelial growth factor (VEGF) gene polymorphisms and stroke. However, their findings remain controversial. The objective of this study was to evaluate the relationships between VEGF gene polymorphisms and stroke by a meta-analysis.

MATERIALS AND METHODS

The PubMed, Embase, China National Knowledge Infrastructure database, Wanfang Chinese database, and VIP Chinese database were systemically searched. Data were extracted by two independent reviewers, and pooled odds ratio (OR) with 95% confidence interval (CI) were calculated.

RESULTS

Ten studies were included, including a total of 2331 cases and 1814 controls for +936C>T, 3040 cases and 2649 controls for -1154G>A. Under the dominant and recessive models, respectively, the overall ORs and 95% CIs of +936 T were 1.44, 1.09-1.90, P = 0.01 (1.53, 1.14-2.05, P = 0.005, in Asians) and 1.19, 0.85-1.65, P = 0.31, and the overall ORs and 95% CIs of -1154 A were 0.98, 0.87-1.10, P = 0.75 and 0.95, 0.82-1.11, P = 0.53. No publication bias was found in this meta-analysis.

CONCLUSIONS

The meta-analysis showed that +936C>T may be a risk factor for stroke, especially in Asians, while -1154G>A was not associated with stroke.