Endothelial Growth Factor Gene Research Articles

The Notch pathway is a critical regulator of angiogenesis in a skin model of ischemia.

The Notch pathway is definitely required for normal vascular development. Although the contribution of Notch in postnatal angiogenesis is the focus of intense investigation, the implication of Notch in reparative neovascularization in the skin remains unexplored. In this study, we investigated Notch changes using a skin model of ischemia. Thirty Sprague-Dawley rats were divided into two groups. In the surgery group (n = 24), a caudally based dorsal skin flap was raised and sutured back into its initial position. In the control group, no surgical procedure was performed. Tissue biopsies were obtained at different time intervals. Tissue specimens were assessed for Delta-like ligand 4 (DLL4) and vascular endothelial growth factor (VEGF) gene expression by real-time polymerase chain reaction (PCR). Immunohistochemical staining was used for detection of DLL4 in tissue materials. Quantitative assessment of skin flap microvasculature was made. Compared with normoperfused tissue, VEGF and DLL4 expressions increased significantly (p < 0.01). Immunohistochemical analysis revealed weak and patchy expression of DLL4 in microvascular endothelial cells of normoperfused tissues. Conversely, DLL4 expression was upregulated in capillary endothelial cells after ischemia. In conclusion, in this study we have shown that the Notch ligand DLL4 is upregulated in skin tissue after ischemia. A deeper understanding of these fundamental principles will aid in the development of new avenues for the treatment of blood vessel-related skin pathologies.

The application of anti-VEGF medication for treatment of neovascular glaucoma

Neovascular glaucoma (NVG) is a refractory ophthalmopathy secondary to multiple ophthalmic and generic vascular diseases, and frequently causes the patients vision loss and impacts their quality of life. The past treatments had very high failure rate: medications did not show good effects, and surgeries led to complications such as intraoperative bleeding, postoperative serious local inflammatory reaction and filtering bleb scar etc. Its pathogenesis is that vascular endothelial growth factor (VEGF) gene overexpression caused by anoxic ischemic retinopathy increases the amount of VEGF in aqueous humor, and then stimulates neovascularization at iris and chamber angel. Anti-VEGF medications being generally applied in ophthalmology in recent years lead the treatment of NVG to a new era. This article briefly summarized the application of anti-VEGF medication in the treatment of NVG. Key words: Glaucoma, neovascular; Anti-VEGF; Treatment

VEGF genetic polymorphisms may contribute to the risk of diabetic nephropathy in patients with diabetes mellitus: a meta-analysis.

Objective. This meta-analysis aimed to investigate a comprehensive and reliable conclusion on the correlations of single nucleotide polymorphisms (SNPs) in the vascular endothelial growth factor (VEGF) gene with the risk of diabetic nephropathy (DN) in patients with diabetes mellitus (DM). Methods. We screened PubMed, Embase, Web of Science, Cochrane Library, CISCOM, CINAHL, Google Scholar, CBM, and CNKI databases for those relevant studies that investigated the association of 14,945 subjects with clinicopathological parameters in gastric cancer. Results. Eleven case-control studies that met all inclusion criteria were included in this meta-analysis. A total of 14,945 subjects were involved, including 3,049 DN patients and 11,896 DM patients. Our meta-analysis results revealed that VEGF rs2010963 and rs3025039 polymorphisms might contribute to the risk of DN in DM patients. Ethnicity-stratified analysis suggested that VEGF genetic polymorphisms were associated with an increased risk of DN among Asians. However, we found no correlations of VEGF genetic polymorphisms with susceptibility to DN among Caucasians. Conclusion. Our findings suggest that VEGF rs2010963 and rs3025039 polymorphisms may contribute to the risk of DN in DM patients, especially among Asians. Thus, VEGF genetic polymorphisms could be useful biomarkers for early diagnosis of DN in DM patients.

Function of expression and actions of peroxisome proliferator-activated receptor β/δ in non-small cell lung cancer

Objective To investigate the function of peroxisome proliferator-activated receptor β/δ (PPARβ/δ) expression in non-small cell lung cancer (NSCLC).Methods Reverse transcription-poly-merase chain reaction (RT-PCR) and PPARβ/δ luciferase activity experiment to detect PPARβ/δ,PPARγ,phospholipase A2 (PLA2),cytochrome C oxidase 2 (Cox-2),prostaglandin E synthase (PGES),prostacyclin synthase (PGIS) expression level in NSCLC cell lines,NSCLC tissue and normal tissue sam-ple from NSCLC patients.The effect of promoting NSCLC cell lines proliferation and survival mediated by PPARβ/δ was analyzed by siRNA and flow cytometer.The function of PPARβ/δ in regulating the express of Cox-2 and vascular endothelial growth factor (VEGF) gene was confirmed by medicine experiment.Results H441 cells had high levels of PPARβ/δ,Cox-2,cPLA2,PGES and PPARc.H358 and H23 cells had intermediate levels of PPARβ/δ.The PPARβ/δ mRNA level was higher in tumor tissues compared to normal tissues.PPARβ/δ had the function of increasing NSCLC proliferation and survival and low level cPGI2 (activate the PPARβ/δ) could improving NSCLC proliferation and viability,prolonging the S cell cycle and shortening the G1 cell cycle.But there nearly was no impact in A549 cells.Decreasing the cell proliferation and viability and promoting apoptosis when knock-down the PPARβ/δ by siRNA and regulating the Cox-2 and vascular endothelial growth factor (VEGF) expression by PPARβ/δ.There was increasing of Cox-2 and VEGF mRNA during the GW501516 (the ligand of PPARβ/δ) treating NSCLC.But,no change was detected in A549 cells.Conclusion Up-expression in NSCLC compared to normal tissues.There are many function of PPARβ/δ in NSCLC including promoting NSCLC proliferation,survival and viability and affecting the Cox-2,VEGF expression.Together,these data suggest that PPARβ/δ might local the central of multiple signaling pathways and control the NSCLC proliferation. Key words: Peroxisome proliferator-activated receptor β/δ; Non-small cell lung cancer; Proliferation; Potential medicine target

Abstract 44: Global Hypomethylation and Promoter Hypomethylation of Flt1 Concurrently Occurred Iin Atherosclerotic Tissues

Background and objectives: Epigenetic alterations have been suggested as a pathological mechanism in atherosclerosis development. However, global and gene-specific epigenetic changes have not been well-known in atherosclerotic tissues yet. We evaluated whether the global methylation and promoter methylation of vascular endothelial growth factor (VEGF) and VEGF receptor (VEGFR) genes of atherosclerotic tissues was different from peripheral leukocytes in carotid stenosis patients. Methods: We used carotid endarterectomy (CEA) tissues and peripheral leukocytes (WBC) collected from 27 patients, who received CEA to remove athoerslcerotic plaque from proximal internal carotid artery. To evaluate global methylation status in the CEA tissue and WBC of each patient, pyrosequencing for long-interspersed nuclear element (LINE) sequence was performed. The evaluation of gene-specific promoter methylation status targeted to angiogenesis-related genes including VEGF, VEGFR1 (Flt1), and VEGFR2 (KDR). The methylation status of each gene was evaluated using methylation specific polymerase chain reaction. The differences of global and gene-specific methylation status of each tested gene were compared between CEA and WBC of all patients. Results: On global methylation status evaluation, LINE methylation was lower in CEA than WBC (CEA, 63.7±1.7; WBC, 65.8±3.3%, p=0.002). CEA tissues also showed significantly lower promoter methylations in VEGFR1 (CEA, 5.3±7.1; WBC, 11.9±9.4%, p=0.007). The methylation status of VEGFR2 (CEA, 21.4±11.5; WBC, 25.5±13.5%, p=0.220) and VEGF (CEA, 19.3±11.8; WBC, 18.0±9.9%, p=0.561) was not statistically different between CEA and WBC samples of the patients. Conclusion: The concurrent decrease pattern of LINE and VEGFR1 suggested that the hypomethylation occurred globally and gene-specifically in angiogenesis-related genes of proximal ICA stenosis. In particular, the VEGFR1 promoter hypomethylation in atherosclerotic tissues might be an epigenetic evidence to explain the increase of angiogenesis increasing inside of atherosclerotic plaque.

Radiation-Induced Cognitive Dysfunction After Different Schemes of Fractionated Whole Brain Irradiation

Radiation-induced cognitive dysfunction is a serious complication of radiation therapy. In humans, numerous cases of radiation damage have been recorded after irradiation for therapeutic purposes. The degree of cognitive dysfunctions and its dependence on biological effective doses should be tested in animal preclinical models to minimize radiation side effects. Fractionated whole brain irradiation was performed according to the following schemes: 18 Fractions of 2 Gy each (36Gy/18), 9 fractions of 4 Gy each (36Gy/9), 6 fractions of 6 Gy each (36Gy/6), with the biological effective dose 36Gy, 50.4Gy, 64.8Gy correspondingly. Cognitive impairment was detected by a Novel object recognition test in 36Gy/18 and 36Gy/9 groups. Recognition memory impairment was increased in inverse proportion to the biological effective dose. In the 36Gy/6 group, increased anxiety and decreased research activity in Spontaneous alternation test in Y-shaped maze were observed. Reactions of astroglia and vascular reactions were evaluated using qPCR of Glial Fibrillar Acid Protein (GFAP) and Vascular Endothelial Growth Factor (VEGF) genes and immunohistochemical analyses of these proteins. Despite of various biological effective doses (and its subsequent increasing in chosen 3 fractionation schemes) a dose-depended effect in the expression of VEGF in the prefrontal cortex and GFAP in hippocampus and in cognitive impairment was not observed. Cognitive impairment after fractionated whole brain irradiation was clearly seen in our research. The described pathologic changes in healthy brain play an important role in development of radiation-induced cognitive dysfunction. Therefore, applicability of radiobiological models for evaluation of effects of fractionated whole brain irradiation on cognitive dysfunction put in question in our study. So we can suggest that it needs essential more researches about the choice an optimal fractionated scheme to minimize side effects of ionizing radiation.

Three single nucleotide polymorphisms of the vascular endothelial growth factor (VEGF) gene and glioma risk in a Chinese population

To investigate the association between three single nucleotide polymorphisms (SNPs) of the vascular endothelial growth factor (VEGF) gene and the risk of glioma in a Han Chinese population. This hospital-based case-control study used polymerase chain reaction-restriction fragment length polymorphism analysis to detect three SNPs (-634 G/C, +936 C/T and +1612 G/A) of the VEGF gene in patients with glioma compared with healthy control subjects. The study investigated 880 patients with gliomas and 880 age- and sex-matched healthy control subjects. Patients with gliomas had a significantly higher frequency of the -634 CC genotype (odds ratio [OR] 1.35, 95% confidence interval [CI] 1.05, 1.75) and the +936 TT (OR 1.73, 95% CI 1.20, 2.48) genotype compared with the control subjects. Patients with glioblastomas had a significantly higher frequency of the -634 CC and +936 TT genotypes. Patients with grade IV gliomas had a significantly higher frequency of the -634 CC and +936 TT genotypes. The +1612 G/A polymorphisms were not associated with glioma risk. The VEGF - 634 CC and +936 TT genotypes were associated with a higher risk of glioma in a Han Chinese population.

Vascular endothelial growth factor (VEGF) −2578C/A and −460C/T gene polymorphisms and lung cancer risk: a meta-analysis involving 11 case–control studies

The aim of this meta-analysis is to generate large-scale evidence on whether common vascular endothelial growth factor (VEGF) gene polymorphisms (-2578C/A [dbSNP: rs699947] and -460C/T [dbSNP: rs833061]) are associated with lung cancer. A literature search of PubMed, Embase, Web of Science, Cochrane Library, and CBM databases was conducted to identify all eligible studies published before May 3, 2013. Crude odds ratios (ORs) with their corresponding confidence intervals (95% CIs) were used to evaluate the strength of the association. Eleven case-control studies were included with a total of 3,861 lung cancer cases and 3,676 controls in this meta-analysis. For the VEGF -2578C/A polymorphism, the combined results showed that there exist highly significant risk factors for individuals carrying the A allele resulting in lung cancer, and the magnitude of this effect was similar in smoker patients and squamous cell carcinoma (SCC) patients. Unlike the situation with the -2578C/A polymorphism, the VEGF -460C/T polymorphism is not associated with the risk of lung cancer in neither Asians nor Caucasians. However, when stratified according to smoking status and histological types of lung cancer, we found that the T allele (-460C/T) was associated with decreased lung cancer risk among nonsmoker patients and SCC patients. Our findings showed that the -2578C/A polymorphism may increase lung cancer risk, especially in smoker patients and SCC patients, whereas the -460C/T polymorphism may decrease lung cancer risk, especially in nonsmoker patients and SCC patients.

Downregulation of activation factors of endothelia and fibroblasts via lysophosphatidic acid signaling in a mouse lung cancer LL/2 cell line

Angiogenesis stimulates the invasive and metastatic process of cancer cells. It is also known that activated fibroblasts promote cancer cell growth and enhance invasive and metastatic potential. Lysophosphatidic acid (LPA) is a biological mediator and interacts with G protein-coupled transmembrane LPA receptors (LPA1 to LPA6). In this study, to assess an involvement of LPA3 on angiogenesis and fibroblast activation, the Lpar3-expressing cells were generated from mouse lung cancer LL/2 cells, which unexpressed LPA3. The Lpar3-expressing cells were maintained in serum-free Dulbecco’s modified Eagle’s medium for 48 h, and cell motility assay was performed with a cell culture Insert. When endothelial F-2 cells and 3T3 fibroblasts were cultured with conditioned medium from the Lpar3-expressing cells, their cell motile activities were significantly lower than the Lpar3-unexpressing (control) cells. Expression levels of vascular endothelial growth factor (Vegf) and fibroblast growth factor (Fgf) genes in the Lpar3-expressing cells were measured by quantitative real time reverse transcription polymerase chain reaction analysis. The expressions of Vegf-A. Fgfa and Fgfb genes in the Lpar3-expressing cells were significantly lower than those in control cells, correlating with the effects on cell motile activities of F-2 and 3T3 cells. These results suggest that LPA signaling through LPA3 may inhibit angiogenesis and fibroblast activation in mouse lung cancer cells.

Vascular endothelial growth factor (VEGF-2578А/С) gene polymorphism in combination with cytokine gene polymorphisms among patients with rheumatoid arthritis

Objective: to study the distribution of the genotypes of the vascular endothelial growth factor (VEGF) gene and their combinations with those of other cytokines among patients with rheumatoid arthritis (RA) and healthy individuals. Subjects and methods. 509 Europeoid women from the eastern regions of Russia, including 374 healthy individuals aged 23-64 years and 135 RA patients aged 27-66 years, were examined. The single nucleotide polymorphism in the promoter region of the genes of VEGC -2578 C/A, tumor necrosis factor-а (TNF-а) -863 C/A, TNF-а -308 G/A, TNF-а -238 G/A, and interleukin (IL) 1β -31 С/T, IL4 -590 С/T, IL6-174 G/C, IL10-1082 G/A, and IL10-592А/С was studied by restriction fragment length polymorphism analysis. Results. Analysis of the frequency of the genotypes of VEGF in combination with other genotypes has revealed a number of highly significant genetic differences between the groups of healthy individuals and RA patients. Among the combined genetic signs (CGS), whose frequency is significantly increased in RA, there is a predominance of heterozygous CA genotypes at the polymorphic position of VEGF -2578 C/A. Among the CGS positively associated with RA, which include homozygous VEGF -2578 variants, there is a preponderance of AA genotypes whereas all 100% of the homozygous genotypes, whose frequency is significantly decreased in RA, correspond to the variant of СС. The CGS whose frequency is altered in RA along with VEGF genotypes most commonly include the genotypes of IL1s, IL4, IL10, IL6, and TNF-а. Conclusion. The pathogenesis of RA calls for comprehensive investigation of the role of the angiogenesis and inflammation regulation genes.

Treatment of retinopathy of prematurity: a review of conventional and promising new therapeutic options.

Retinopathy of prematurity (ROP), a retinal vascular disease of premature infants, continues to be a major cause of preventable childhood blindness all over the world. The incidence of ROP varies among countries, being influenced by the quality of the level of neonatal intensive care. Here, we discuss the potential treatments that are now available or will soon or probably be available for ROP. Although ablation of the avascular retina with laser photocoagulation remains the current gold standard and well established therapy for ROP, some new therapeutic options including angiostatic therapies are being explored based on our knowledge of the pathophysiology of the ROP and complications and efficacy of laser treatment. However, prevention of the development of severe ROP and screening for ROP seem to be the best strategy in avoiding visual impairment caused by ROP in premature infants. New therapeutic interventions including vascular endothelial growth factor antibody administration, gene therapy and supplemental therapies should be supported with evidence-based data for the treatment of ROP.

The role of genetic polymorphisms at the chromosomes 5p15, 6p12, 6p21 and 15q25 in non-small-cell lung cancer prognosis: a Portuguese prospective study

Genome Wide Association Study (GWAS) variants on chromosome 15q25 and 5p15 and genetic polymorphisms on the vascular endothelial growth factor (VEGF) gene showed that they may contribute to lung carcinogenesis. Therefore, this study was performed in order to assess the role of GWAS, and VEGF variants in non-small-cell lung cancer (NSCLC) prognosis.

Analysis of the Efficiency of Gene-Cell Therapy in Transgenic Mice with Amyotrophic Lateral Sclerosis Phenotype

Amyotrophic lateral sclerosis is a neurodegenerative disease characterized by progressive death of cerebral and spinal motorneurons. Using behavioral tests we studied the efficiency of gene-cell therapy in SOD1 G93A transgenic mice receiving xenotransplantation of human umbilical cord blood mononuclear cells genetically modified with adenoviral vectors encoding vascular endothelial growth factor (VEGF) and reporter green fluorescent protein (EGFP) genes. The cells were transplanted to mice on week 27 of life (preclinical stage of the disease). Behavioral tests (open field, grip strength test) showed that transplantation of umbilical cord blood mononuclear cells expressing VEGF significantly improved the parameters of motor and explorative activity, grip strength, and animal survival. Thus, gene-cell therapy based on genetically modified mononuclear cells expressing VEGF can be efficient for the treatment of amyotrophic lateral sclerosis.

Associations of vascular endothelial growth factor (VEGF) gene and cytokine (IL-1B, IL-4, IL-6, IL-10, TNFA) genes combinations with type 2 diabetes mellitus in women

Aim. To study the association between vascular endothelial growth factor (VEGF) and cytokine (IL1B, IL4, IL6, IL10 and TNFA)gene polymorphism combinations with type 2 diabetes mellitus (T2DM) in women. Materials and methods. 374 Caucasian women without carbohydrate metabolism disorders from 23 to 68 years of age and 212 womenwith T2DM from 28 to 69 years of age were included in the study. The combinations of polymorphism А-2578С, С+936Т in VEGFgene with polymorphism in IL1B С-31Т, IL4 С-590Т, IL6 G-174C, IL10 A-592C and А-1082G, TNFA А-238G, A-308G and A-863Cwere studied. Results. Analysis revealed 52 combined genetic variations with different rate of occurrence between diabetic and control groups(р

Methodological remarks concerning the recent meta-analysis on vascular endothelial growth factor polymorphism and endometriosis risk

We read with great interest the recent meta-analysis by Liang et al. [1], which evaluated the association between vascular endothelial growth factor (VEGF) gene polymorphisms and endometriosis risk. Eleven studies were included in their meta-analysis and their study found that the VEGF ?936 C/T gene polymorphism is a risk factor for endometriosis, and not -460T/C, ?405G/C, -2578A/C, -1154G/A. Nevertheless, close inspection of the study revealed some methodological issues that are worth mentioning and clarifying. The major issue of this meta-analysis is the lack of subgroup analysis, which may make the results untrustworthy. For the ?936 C/T; -460T/C and ?405G/C polymorphisms, there were enough studies for subgroup analysis. The most obvious differences among the included studies were the ethnicity that the included patients in the original studies came from. For example, some studies in this meta-analysis were based on Asian populations, while the other studies were based on Caucasian patients. As previously described, ethnicity can strongly influence the distribution of gene polymorphisms [2]. Therefore, it is essential to perform the subgroup analysis by ethnicity in meta-analysis of Liang et al. [1]. For the VEGF ?936 C/T polymorphism, Liang et al. [1] found that it was associated with an increased endometriosis risk. However, when stratifying for ethnicity, there was no significant association between VEGF gene ?936 C/T polymorphism and endometriosis among Asians (TT ? TC vs. CC: OR = 1.20, 95 % CI 0.92–1.55, P = 0.18, TC vs. CC: OR 1.18, 95 % CI 0.90–1.54, P = 0.23) and Caucasians (TT ? TC vs. CC: OR = 1.18, 95 % CI 0.99–1.40, P = 0.06, TC vs. CC: OR 1.19, 95 % CI 1.00–1.42, P = 0.05). For the VEGF ?405G/C polymorphism, Liang et al. [1] did not detect any association in any comparison model. However, when stratifying for ethnicity, a significantly decreased association was observed between VEGF ?405G/C polymorphism and endometriosis among Asians (CC ? GC vs. GG: OR = 0.74, 95 % CI 0.59–0.93, P = 0.009, GC vs. GG: OR 0.76, 95 % CI 0.60–0.97, P = 0.03), while a significantly increased association was found between VEGF ?405G/C polymorphism and endometriosis among Caucasians (CC ? GC vs. GG: OR = 1.17, 95 % CI 1.00–1.37, P = 0.04). Moreover, close inspection of the data provided by the authors (Table 1 in the meta-analysis) revealed an issue that is worth mentioning. The data reported by Liang et al. for the study of Altinkaya et al. [3]. about VEGF ?405G/C polymorphism do not seem to be in line with the data provided by Altinkaya et al. [3] in their original publication. The numbers reported by Liang et al. for CC, CG, GG, in cases for Altinkaya et al. [3], were 22-57-16, while the numbers for CC, CG, GG, in cases were 25-57-16 in Altinkaya et al.’s [3] original study. In conclusion, this letter points out interesting methodological aspects concerning the subgroup analysis by race; and it would be valuable if the authors could take into account this remark.

Impact of VEGF polymorphisms on the severity of peripheral artery disease in diabetic patients

Objective. To determine the potential genotype vascular endothelial growth factor (VEGF) gene differences in diabetic patients with peripheral arterial disease (PAD), which might be associated with different stages of the vascular disease. Methods. A study was conducted with type 2 diabetic patients with PAD [n = 70; 32 intermittent claudication and 38 critical limb ischaemia (CLI)]. Genotyping of the VEGF gene insertion/deletion − 2549, − 2578 C/A and +405 G/C polymorphisms was done in both groups and correlated them with the severity of PAD. We compared serum VEGF levels in both groups. Results. There was a higher frequency of +405 CC and − 2578 CC genotypes in claudication group [(31.3% vs. 5.4%, p = 0.01) and (37.5% vs. 15.8%, p = 0.05), respectively]. The presence of +405 GG and − 2578 AA genotypes was more common among CLI patients [(57.8% vs. 37.5%, p = 0.01) and (42.1% vs. 18.8%, p = 0.05), respectively]. There were higher serum VEGF levels in patients with CLI (p = 0.029). Conclusions. We found preliminary evidence regarding the association between VEGF polymorphisms and different stages of PAD in diabetic patients.

Response to: Flavia Magazoni Gonçalves, Marcello Rizzatti Luizon, Jose G. Speciali: “Haplotypes in candidate genes related to nitric oxide pathways and vascular permeability associated with migraine with aura”

Migraine is regarded as a “neurovascular disorder” presenting with dysfunctions of both the brain and the vascular system. However, the initial spark causing migraine appears to be generated within the brain, which is supported by results from recent genome-wide association studies (GWAS) [1, 2], while vascular phenomena are likely epiphenomena [3]. In addition, migraine with aura has been associated with an increased risk for ischemic stroke, while such an association is less clear for other vascular disorders [4]. In contrast, migraine without aura, which is far more common than migraine with aura, does not seem to carry an increased risk for vascular disease. So, how are the brain and the vasculature linked in migraine? The short answer is: We do not really know. A longer answer would first have to state that the link is likely complex and may include shared genetics. One approach to decipher this link is to investigate variants in genes involved in vascular tone control, including genes coding for the nitric oxide synthases (NOS), a family of enzymes found in the nervous system, cardiovascular system, and endothelium [5]. Results at the single variant level from studies investigating NOS2 and NOS3 genes [6–11] as well as the vascular endothelial growth factor (VEGF) gene [12] in migraine did not give a clear answer. Reasons may include the wide phenotypic spectrum of migraine, differences in study design, genetically heterogeneous populations, and limited sample sizes. Analyses utilizing the integrated information from multiple gene variants such as haplotype analyses may be beneficial as suggested by recent studies [10–12]. However, it also has to be taken into consideration that studies using even more comprehensive and more efficient approaches like GWAS failed to identify any vascular-related genes among migraineurs [1, 2, 13]. What we have learned from studying migraine genetics so far? First, migraine is clinically and genetically heterogeneous making it notoriously difficult to identify susceptibility genes. Any susceptibility gene variant will modify the risk for migraine to only a small to moderate degree; hence, large studies are needed to detect them. Second, any association found—whatever study design used—must be replicated in independent samples/cohorts to make us confident that the associations seen are true and not spurious. Third, novel ways of analyses, for example, investigating the interaction of gene variants may help to understand why and how certain variants influence migraine pathophysiology. However, in order to avoid spurious results interaction analyses should only be performed among gene variants for which there is strong evidence of an association with migraine and if there is enough power to really detect potential interactions.

Two Polymorphisms (Rs699947, Rs2010963) in the VEGFA Gene and Diabetic Retinopathy: An Updated Meta-Analysis

Objective: The vascular endothelial growth factor (VEGFA) gene has been suggested to play an important role in the pathogenesis of diabetic retinopathy (DR). However, the results have been inconsistent. In this study, we performed a meta-analysis to clarify the associations between VEGFA polymorphisms and DR risk across different populations. Methods: Published literature from PubMed and EMBASE were retrieved. Pooled odds ratio (OR) with 95% confidence interval (CI) was calculated using fixed or random-effects model. Results: Eight studies (1204 cases and 1198 controls) for rs699947 polymorphism and 10 studies (1666 cases and 1782 controls) for rs2010963 polymorphism were included in the meta-analysis. The results indicated that rs699947 polymorphism was significantly associated with DR among Europeans under a dominant model (OR = 1.47, 95% CI = 1.07–2.02), but not among East Asians under all genetic models. In addition, there was no significant association between rs2010963 polymorphism and DR under all genetic models by ethnicity and type of DR. Conclusions: The present meta-analysis indicated that rs699947 polymorphism might be associated with the risk of DR among Europeans but not among East Asians; rs2010963 polymorphism was not associated with DR among either ethnic group.

Enhanced Vascular Endothelial Growth Factor Gene Expression in Ischaemic Skin of Critical Limb Ischaemia Patients

Objectives. To perform a quantitative analysis of the vascular endothelial growth factor (VEGF) gene transcription in the skin of ischemic legs and provide information for VEGF in the pathogenesis in critical limb ischemia (CLI). Methods. Skin biopsies were obtained from 40 patients with CLI. Control samples came from 44 patients with chronic venous disease. VEGF gene expression was analysed using quantitative polymerase chain reaction. Results. Patients with CLI had higher skin VEGF expression than control group (RQ: 1.3 ± 0.1 versus 1, P = 0.04). Conclusions. We found an association between ischemic skin and an elevated VEGF expression in legs from patients with CLI. These data support that the mechanism for VEGF upregulation in hypoxia conditions is intact and acts appropriately in the ischaemic limbs from patients with CLI.

Revascularization and osteogenesis during repair of bone defects with tissue-engineered bone of nano-hydroaoatite crystal/polyamide 66/rabbit osteoplast/vascular endothelial growth factor

Objective To employ the vascular endothelial growth factor (VEGF165) gene transfected rabbbit osteoplast to combine with the porous nano-hydrxyapatite crystal (n-HA)/polyam ide 66(/PA66) so as to evaluate the osteogenesis and rapid revascularization early after repair of the rabbit radius bone defects with the tissue-engineered bone (n-HA/PA66/osteoplast/VEGF165). Methods The animal models of bilateral radius bone defects were created in 56 New Zealand white rabbits that were then randomly divided into Group A and Group B.In Group A, the animals were implanted with n-HA/PA66on the left bone defects (Group Al) and with n-HA/PA66/VEGF165 composite materials on the right bone defects (Group A2). In Group B, the animals were implanted with n-HA/PA66/osteoplast/VEGF165 composite materials on the left side (Group B1) and with n-HA/PA66/osteoplast on the right side (Group B2).Gross, digital radiography, histological sections, vessel count and scanning electron microscopy (SEM) were performed at 2, 4, 8 and 12 weeks after operation. Results The osteogenesis and revascularization in Group B1 was superior to that in the other groups at each time point, with statistical difference (P ＜0.05).The revascularization and osteogenesis in Groups B1 and B2 was far better than that in Groups A1 and A2, with no statistical difference between Group A1 and Group A2. Conclusions The new tissue-engineered bone (n-HA/PA66/osteoplast/VEGF165) has a perfect osteogenetic effect and can promote rapid revascularization and the bone healing in the early stage after repair of the bone defects. Key words: Hydroxyapatites; Vascular endothelial growth factors; Bone defect