Genetic polymorphisms of vascular endothelial growth factor in severe pre-eclampsia

An Investigation of the Association Between Vascular Endothelial Growth Factor +405 G/C Polymorphism and Acute Liver Transplant Rejection in Iranian Liver Transplant Recipients

OBJECTIVES

Vascular endothelial growth factor is an endothelial-specific growth factor that promotes endothelial cell proliferation, differentiation, and survival; mediates endothelium-dependent vasodilatation; induces microvascular hyperpermeability; and participates in interstitial matrix remodeling. The aim of the present study was to investigate the association between +405 G/C polymorphism of vascular endothelial growth factor and the risk of liver rejection in liver transplant recipients.

MATERIALS AND METHODS

The present study included 124 patients with liver disease that led to liver transplant. There were 22 patients who experienced histologically proven acute liver rejection, and the other 102 patients showed no rejection. Both groups were matched for sex and age. The VEGF+405 G/C polymorphism was evaluated by the polymerase chain reaction-restriction fragment-length polymorphism method.

RESULTS

Our analyses showed no significant relationships between genotypes and alleles of +405 G/C and risk of acute liver transplant rejection.

CONCLUSIONS

Our report indicated that there was no association between the carrier states of +405 G/C gene polymorphism of vascular endothelial growth factor and acute rejection or nonrejection of liver transplant.

Polymorphisms of vascular endothelial growth factor and recurrent implantation failure: a systematic review and meta-analysis

PURPOSE

To investigate the associations between polymorphisms of vascular endothelial growth factor (VEGF) with recurrent implantation failure (RIF).

METHODS

We performed the systematic review and meta-analysis by searching databases of PubMed, EMBASE, OVID, and CNKI (China National Knowledge Infrastructure) for studies that evaluated the associations between VEGF polymorphisms with RIF. Meta-analysis was performed if the polymorphism was studied by more than two case-control studies. Data were analyzed using R software. Odds ratios (ORs) with 95% confidence intervals (CIs) were reported to assess the associations.

RESULTS

Nine VEGF polymorphisms (-1154G > A, -460T > C, +405G > C, -7C > T, -634C > G, -2578C > A, +936C > T, 5C > T, -583C > T) were systematically reviewed. Meta-analysis was performed on VEGF -1154 G > A polymorphism. Three case-control studies consisted of 683 women were included in the quantitative meta-analysis (305 RIF patients and 378 controls). Results showed that VEGF -1154A allele was significantly associated with RIF (OR 1.39, 95% CI 1.08-1.78, P-value = 0.01). The dominant genetic model showed that VEGF 1154AA plus VEGF 1154AG genotypes were more frequent in RIF patients than VEGF 1154GG genotype (OR 1.56, 95% CI 1.10-2.20, P-value = 0.01). However, the result under the recessive genetic model showed no significant difference (OR 1.67, 95% CI 0.92-3.03, P-value = 0.09).

CONCLUSION

VEGF -1154A allele may serve as one of the predisposing factors of RIF. Women with VEGF 1154 AA/GA genotypes were at higher risk of RIF. However, we should consider the haplotype effect of VEGF polymorphisms in future studies.

A meta-analysis of the vascular endothelial growth factor polymorphisms associated with the risk of pre-eclampsia

Backgroud: Pre-eclampsia (PE) is a common pregnancy-induced hypertension disease. Some case–control studies reported the association between vascular endothelial growth factor (VEGF) gene polymorphisms (rs3025039, rs2010963) and PE risk. However, these associations were inconsistent in several studies. Therefore, we conducted this meta-analysis to assess the role of VEGF gene polymorphisms in PE more precisely.

Methods: Eligible studies were searched in PubMed, Embase, Web of Science and Chinese (Chinese National Knowledge Infrastructure (CNKI) and WanFang) databases. Statistical analyses were performed by Stata 12.0 software. Odds ratio (OR) and 95% confidence interval (CI) were used to assess the strength of the association. In addition, subgroup analyses, sensitive analyses and publication bias analyses were performed to further assess this meta-analysis.

Results: In total, 21 studies were included in the meta-analysis covering 2018 cases and 2632 controls. There were significant associations between VEGF polymorphisms (rs3025039, rs2010963) and PE risk in the overall populations. In the subgroup analyses, we found that rs3025039 polymorphism was associated with the increased risk of PE among Chinese. As for rs2010963 polymorphism, a significant association was observed in subgroup of Caucasian.

Conclusion: The present study suggested that the two VEGF gene polymorphisms (rs3025039, rs2010963) are associated with increased risk of PE in different ethnic groups, which means that the targets may be useful genetic markers for early prediction of PE.

Cell Specific Expression of Vascular Endothelial Growth Factor Receptor-2 (Flk-1/KDR) in Developing Mice Embryo and Supporting Maternal Uterine Tissue during Early Gestation (D4-D7)

Background

Vascular endothelial growth factor (VEGF) and the corresponding receptors play key role in vasculogenesis and angiogenesis processes. VEGF is one of the prime candidates in regulating embryo implantation by increasing vascular permeability. VEGF receptor-2, also called Flk-1/KDR, is one of the prime receptor which is actively involved in the execution of various functions of VEGF. However, precise role of this receptor during early gestation period is yet to be addressed. In the present study, expression of Flk-1/KDR during peri-implantation mice uterus as well as fetal-maternal tissues from day 4-day 7 (D4-D7) of gestation was investigated.

Materials and Methods

In this experimental study, localization of Flk-1/KDR was investigated by immunohistochemistry and immunofluorescence techniques, in paraffin embedded tissue sections. Flk-1/KDR protein and mRNA expressions were investigated by western blotting and quantitative reverse transcription polymerase chain reaction (qRT-PCR), respectively. Effects of ovarian steroids on expression of Flk-1/KDR were also assessed by estrogen and progesterone antagonist treatment.

Results

Uterine tissue on D4 showed strong expression of Flk-1/KDR in luminal and uterine glandular epithelium. On D5 and D6, differential expression of Flk-1/KDR was evidenced in certain cell types of the embryo, maternal tissues and fetal-maternal interface with varied intensity. Flk-1/KDR was specifically expressed in the ectoplacental cone (EPC) and various cells of the embryo on D7. Flk-1/KDR expression was not evidenced in the estradiol-17β (E2) and progesterone (P4) antagonist treated uterus. Western blotting result revealed presence of Flk-1/KDR protein in the all gestation days, except antagonist treated uterus. qRT-PCR analysis showed significant increase of Flk-1/KDR mRNA transcript on D6 and D7.

Conclusion

Spatial-temporal expression of Flk-1/KDR during peri-implntation period in mice uterus especially in the feto-maternal interface was observed. This spatio-temporal specificity as well as increased expression of Flk-1/KDR could be one of the determinants for establishment of fetal-maternal cross talk during the critical period of development.

Genetic markers for preeclampsia in Peruvian women

BACKGROUND

Preeclampsia is a multiorgan disorder associated with maternal and perinatal morbi-mortality. In Peru, incidence is 10% and accounts for 22% of maternal deaths. Genome and genetic epidemiological studies have found an association between preeclampsia and genetic polymorphisms.

OBJECTIVE

To determine the association of the vascular endothelial growth factor (VEGF) +936 C/T and +405 G/C, interleukine-6 (IL-6) -174 G/C, IL-1β-511 C/T, Apo A-1-75 G/A, Apo B-100 2488 C/T (Xbal) polymorphisms with preeclampsia in pregnant Peruvian women.

METHODS

Were included preeclamptic and healthy (control) pregnant women. Maternal blood samples were subjected to DNA extraction, and molecular genetic analysis was conducted using the PCR-RFLP technique and following a specific protocol for each gene. Allele and genotypic frequencies in the cases and controls were compared.

RESULTS

No association was found between the VEGF+936C/T and VEGF+405 polymorphisms and preeclampsia. The frequencies of the GG genotypes and the G allele of the -174 G/C polymorphism in the IL6 gene in preeclamptic and controls showed significant differences, with higher frequencies in cases. For the -511 C/T polymorphism of the IL-1β gene, no significant differences were found in the frequencies of TT genotypes compared with CT+CC. The genotypes and alleles of the Apo-A1-75 G/A and Apo-B100 Xbal variants showed no significant differences between cases and controls.

CONCLUSION

No association was found between the studied genetic markers and preeclampsia. However, in the -174G/C polymorphism of the IL-6 gene, significant differences were found mainly in the GG genotype and G allele.

The Effects of Selenium Supplementation on Clinical Symptoms and Gene Expression Related to Inflammation and Vascular Endothelial Growth Factor in Infertile Women Candidate for In Vitro Fertilization

This study was performed to determine the effects of selenium supplementation on clinical symptoms and gene expression related to inflammatory markers in infertile women with polycystic ovary syndrome (PCOS) who were candidate for in vitro fertilization (IVF). Thirty-six women candidate for IVF were recruited in this randomized double-blinded, placebo-controlled trial. They (n = 18/group) were randomly assigned into intervention groups to take either 200 μg/day of selenium or placebo for 8 weeks. RT-PCR findings indicated that selenium supplementation downregulated gene expression of interleukin-1 (IL-1) (P < 0.004) and tumor necrosis factor alpha (TNF-α) (P = 0.02) in lymphocytes of patients with PCOS compared with the placebo. In addition, selenium supplementation upregulated gene expression of vascular endothelial growth factor (VEGF) (P = 0.001) in lymphocytes of patients with PCOS compared with the placebo. Selenium supplementation had no significant effect on clinical symptoms and gene expression of IL-8 (P = 0.10) and transforming growth factor beta (TGF-β) (P = 0.63). Overall, our findings documented that selenium supplementation for 8 weeks to infertile women candidate for IVF improved IL-1, TNF-α, and VEGF gene expression, though selenium had no effect on clinical symptoms and, IL-8 and TGF-β gene expression. Clinical trial registration number: http://www.irct.ir: IRCT20170513033941N23.

The effect of prednisolone on endometrial VGEF concentrations, Gene polymorphisms and pregnancy outcome in women with polycystic ovary syndrome: A retrospective cohort study

PCOS (Polycystic Ovary Syndrome) occurs due to hyperandrogenism, excessive androgen, abnormal growth, steroidogenesis and seems to be associated with abnormal Vascular endothelial growth factor (VEGF) level in serum. The treatment is provided on the basis of body symptoms to mute the excess production of hormone. The study assessed the effect of prednisolone treatment on the concentration of VEGF, pregnancy outcomes and variants of VEGF SNPs. In the current retrospective study, the samples were collected from PCOS female patients who received prednisolone and those who did not received it, were compared along with control, in terms of pregnancy results and the association complications. The results inferred that the prednisolone made the concentration of VEGF significantly to normal levels along with other pregnancy-related and growth-related hormones. But the reduced normal limits were achieved only among few patients whereas no significant improvement found in the women who received prednisolone and control, in terms of pregnancy outcomes or complications. Further, there were no relations between the impact of treatment and the variants of VEGF SNPs. To conclude, there is no solid evidence found in the current study with regards to notable beneficial effect when the patients were treated with prednisolone, either in pregnancy outcomes or VEGF SNPs. The current study results should be considered only as a preliminary one since the genetic polymorphisms tend to exhibit different results based on population, ethnic groups etc. The results yielded may not be generalized due to differences in genetic background.

Effects of maternal and fetal vascular endothelial growth factor a single nucleotide polymorphisms on pre-eclampsia: A hybrid design study

Maternal and fetal gene variants play important roles in the pathology of pre-eclampsia (PE), but most studies investigating the associations between vascular endothelial growth factor A (VEGF-A) gene variates and PE focusing on maternal genetic effects. The present study firstly used a hybrid case-parent and control-mother study design investigating the both maternal and fetal effects of VEGF-A gene polymorphisms on PE among Han Chinese pregnant women. This study recruited 221 PE patients with their partners and infants and 345 normotensive women with their infants. The current study found that, in both maternal and fetal dominant model (GC + CC/GG), VEGF-A rs2010963 polymorphism was associated with an increased risk of PE (OR = 1.85, 95% CI: 1.25-2.75; OR = 1.90, 95% CI: 1.28-2.83, respectively). In the log-liner model analyses, offspring carrying the genotype of GC or CC in the rs2010963 polymorphism could increase the risk of maternal PE (OR = 1.84, 95%CI: 1.18-2.86; OR = 1.89, 95%CI: 1.02-3.49, respectively) compared to the offspring with GG. Meanwhile, the present study also found that passive smoking had a significant interaction with maternal rs2010963 polymorphism (P_LRT = 0.022) on the risk of PE.

Vascular endothelial growth factor C/A 2578 gene polymorphism and umbilical artery Doppler in preeclamptic women

INTRODUCTION

Preeclampsia is strongly associated with placental hypoperfusion. Genetic factors have an impact on the pathogenesis of preeclampsia. The aim is to assess the association of Vascular Endothelial Growth Factor (C2578A) gene polymorphism with the occurrence and severity of preeclampsia and the umbilical artery Doppler changes among preeclamptic women.

MATERIALS AND METHODS

This case-control study was conducted in clinical and Chemical pathology and Obstetrics departments in Beni- Suef University, Egypt. Two hundred and ninety pregnant women above 20 weeks gestational age until delivery were divided into 2 main groups. The patient group included 145 preeclamptic women who were further sub grouped according to the severity of preeclampsia into 82 severe and 63 mild cases. Control group included 145 normotensive pregnant women. Our primary outcome was detection of VEGF C 2578 A gene mutations by a polymerase chain reaction. A secondary outcome was Doppler changes in the pulsatility index of the umbilical artery compared with VEGF genotypes.

RESULTS

Our study showed that VEGF C 2578 A genotype and alleles frequencies were not related to the occurrence of preeclampsia (p-value 0.513 and 0.549, respectively), odds ratio (95%CI) 1.154 (0.724-1.848). Mild preeclamptic cases showed no significance comparing VEGF genotypes studied and pulsatility index of the umbilical artery. However, severe cases showed p-value < 0.0001.

CONCLUSION

We concluded that VEGF 2578C/A polymorphism had no association with the occurrence of preeclampsia in studied groups, whereas there was a significant relationship among severe cases between CA and CC genotypes and pulsatility index of the umbilical artery.

MTHFR and F5 genetic variations have association with preeclampsia in Pakistani patients: a case control study

BACKGROUND

To study the role of single nucleotide variants (SNVs) of genes related to preeclampsia in Pakistani pregnant women.

METHODS

After ethical approval and getting informed consent; 250 pregnant women were enrolled and equally divided into two groups (125 preeclamptic cases and 125 normotensive pregnant women). Demographic details and medical history were recorded, and 10 ml blood sample was obtained for DNA extraction. The tetra-primer amplification refractory mutation system (ARMS) assays were developed for assessing the variants of three preeclampsia related genes; F5, MTHFR and VEGFA. An association of six SNVs; F5:c.1601G > A (rs6025), F5:c.6665A > G (rs6027), MTHFR: c.665C > T (rs1801133), MTHFR: c.1286A > C (rs1801131), VEGFA: c.-2055A > C (rs699947) and VEGFA: c.*237C > T (rs3025039) with preeclampsia was determined by using different genetic models.

RESULTS

Genotyping of the SNVs revealed that patients with MTHFR:c.665C > T, have increased susceptibility to preeclampsia (CT versus CC/TT: OR = 2.79, 95% CI = 1.18-6.59; P* = 0.046 and CT/TT vs CC: OR = 2.91, 95% CI = 1.29-6.57; P* = 0.0497, in overdominant and dominant models, respectively), whereas F5:c.6665A > G, (A/G vs AA/GG: OR = 0.42, 95% CI = 0.21-0.84; P* = 0.038 in overdominant model) and MTHFR:c.1286A > C, (CC versus AA: OR = 0.36, 95% CI = 0.18-0.72; P* = 0.0392 in codominant model) have significantly decreased risk for preeclampsia. F5:c.1601G > A, VEGFA: c.-2055A > C and VEGFA: c.*237C > T variants revealed no relationship with the disease.

CONCLUSION

This is the first case control study describing the protective role of F5:c.6665A > G against preeclampsia in any world population. In addition, the present study confirmed the association and role of MTHFR gene variations in the development of preeclampsia in Pakistani patients. Further genetic studies may be required to better understand the complex genetic mechanism of SNVs in preeclampsia related genes in pregnant women.

Haplotype analysis of VEGF gene polymorphisms in polycystic ovary syndrome

This study evaluated the association of polymorphisms of VEGF (endothelial vascular growth factor) gene + 936C/T (rs3025039), 1154 G/A (rs 1570360) and -2578 C/A (rs 699947) in patients with polycystic ovary syndrome (PCOS) and to perform the haplotypes formed by the alleles in the Brazilian population. A total of 110 women without PCOS and 112 women with PCOS were included in the study. Genotyping analyses were performed using the PCR-RFLP assays (rs 3025039 and rs 699947) and by allelic discrimination using the real-time PCR technique (rs 1570360). In the univariate analysis, we observed a significant difference between the groups for the polymorphism rs 1570360 and this polymorphism presented statistical differences between the groups for the recessive model (p = .04). The frequency of the T-G-C haplotype showed a statistically significant difference between women with PCOS and controls (p = .05). The -2578 A/C polymorphism was more frequent in the control group, which may be associated with a protective characteristic for the PCOS manifestation. In the sample analysis, polymorphism rs 1570360 is associated with PCOS and the T-G-C haplotype could be associated with protective factors.

Association between Vascular Endothelial Growth Factor Gene Polymorphisms and Pre-Eclampsia Susceptibility: An Updated Meta-Analysis

Objectives: The aim of this study was to assess the genetic association between vascular endothelial growth factor (VEGF) gene polymorphisms and the risk of pre-eclampsia (PE).Methods: A systematic literature search of several databases (PubMed, Embase, and the China National Knowledge Infrastructure (CNKI)) was conducted for case-control trials comparing VEGF polymorphisms (+936C/T, -634G/C, -2578C/A, and -1154G/A) with the risk of PE. Meta-analysis was performed using the Stata 12.0 software.Results: Twenty-three case-control studies on a total of 2597 PE patients and 3075 controls were included in our meta-analysis. The +936C/T polymorphism was observed to be associated with the risk of PE in the overall population (T vs. C: odds ratios (OR) = 1.434, 95% confidence interval (CI) = 1.120-1.836, P = .004). However, the -634G/C, -2578C/A, and -1154G/A polymorphisms showed no association with the risk of PE. A subgroup analysis based on ethnicity found that the +936C/T polymorphism was associated with the risk of PE in both Europeans and Asians. Furthermore, the -634G/C polymorphism was found to be associated with the risk of PE in Europeans (C vs. G: OR = 1.428, 95% CI = 1.141-1.778, P = .002). The polymorphisms at other loci were not associated with the risk of PE.Conclusion: This meta-analysis suggests that VEGF +936C/T polymorphism, rather than -634G/C, -2578C/A, or -1154G/A polymorphisms, is associated with the risk of PE in the overall study population. However, the -634G/C polymorphism may be associated with the risk of developing PE in Europeans.

Analysis of VEGF gene polymorphisms and serum VEGF protein levels contribution in polycystic ovary syndrome of patients

Vascular endothelial growth factor (VEGF) is a well-known factor in reproductive function and contributes to the pathogenesis of polycystic ovary syndrome (PCOS). Genetic variations in VEGFA gene were suggested to contribute alterations in VEGF secretion and PCOS. This study evaluated the association of VEGFA SNPs with altered VEGF secretion level and PCOS among ethnically-matched control women. This prospective case-control study was conducted from 2016 to 2018 and comprised of 55 women with PCOS and 52 control subjects. ELISA was used to measure VEGF levels; and various other related bio chemicals whereas the genotyping of VEGFA variants was performed through the analysis of nine SNPs of VEGF. PRL, E2, PRGE testosterone and glucose level were found to be insignificantly different. The levels of FSH, LH, LH/FSH, TT, insulin, SHBG and HOMA-IR were significantly higher in the study group. Among the nine tested variants of VEGF SNPs, two SNPs rs3025020 and rs833061, consisted of TT (Recessive and Dominant homozygous, respectively) which were marginally higher in test. The SNP rs1570360 had significantly higher GG allele (32.73%) which was recessive homozygous. There was no significant difference observed in genotype frequencies related to higher value of VEGF. The genotype frequencies for the studied SNPs were in alignment with Hardy-Weinberg equilibrium (HWE). The mean serum VEGF levels got significantly increased in PCOS group. No significant association was found between VEGF genotypes and its serum levels. VEGF levels in rs699947 (AA-major homozygous), rs3025039 (CC-major homozygous) and rs833061 (TT & CC-major & minor homozygous) genotypes were significantly higher in PCOS. The study results evidently proved that the allelic variants in genes may be a factor for PCOS and VEGF serum levels with respect to few SNP variants only. These findings indicated that VEGF may be involved in PCOS status and confirmed the previous association between genetic variants in VEGF, serum level of VEGF protein and PCOS.

Association between the vascular endothelial growth factor gene polymorphisms and the risk of polycystic ovary syndrome in Northern Chinese women

The present study aimed to investigate whether the single nucleotide polymorphisms (SNPs) rs2010963 and rs833061 in vascular endothelial growth factor (VEGF) gene is correlated with the risk of polycystic ovary syndrome (PCOS) in Northern Chinese women, as a preliminary study. This case-control study comprised 118 women with PCOS and 130 healthy women as controls. Genotyping of the two polymorphisms within the VEGF gene 5'-untranslated region and promoter region were performed using polymerase chain reaction ligase detection reaction method. The data showed that there was a significant difference in the genotype and allele distribution of the rs2010963 polymorphism between the PCOS group and the control group (p = .020 and .033, respectively). The women carrying the C allele (G/C + C/C genotype) had a lower risk of PCOS compared with the women with G/G genotype [odds ratio (OR = 0.55; 95% confidence interval (CI) = 0.33-0.91]. Our study shows for the first time that the rs2010963 polymorphism may be associated with a risk of PCOS in Northern Chinese women.

Non-additive effects of ACVR2A in preeclampsia in a Philippine population

BACKGROUND

Multiple interrelated pathways contribute to the pathogenesis of preeclampsia, and variants in susceptibility genes may play a role among Filipinos, an ethnically distinct group with high prevalence of the disease. The objective of this study was to examine the association between variants in maternal candidate genes and the development of preeclampsia in a Philippine population.

METHODS

A case-control study involving 29 single nucleotide polymorphisms (SNPs) in 21 candidate genes was conducted in 150 patients with preeclampsia (cases) and 175 women with uncomplicated normal pregnancies (controls). Genotyping for the GRK4 and DRD1 gene variants was carried out using the TaqMan Assay, and all other variants were assayed using the Sequenom MassARRAY Iplex Platform. PLINK was used for SNP association testing. Multilocus association analysis was performed using multifactor dimensionality reduction (MDR) analysis.

RESULTS

Among the clinical factors, older age (P <  1 × 10-4), higher BMI (P <  1 × 10-4), having a new partner (P = 0.006), and increased time interval from previous pregnancy (P = 0.018) associated with preeclampsia. The MDR algorithm identified the genetic variant ACVR2A rs1014064 as interacting with age and BMI in association with preeclampsia among Filipino women.

CONCLUSIONS

The MDR algorithm identified an interaction between age, BMI and ACVR2A rs1014064, indicating that context among genetic variants and demographic/clinical factors may be crucial to understanding the pathogenesis of preeclampsia among Filipino women.

[Polymorphism in the regulatory regions -С2578A and +C936T of the vascular endothelial growth factor (VEGF-A) gene in Russian women with rheumatoid arthritis]

AIM

To analyze polymorphism in the regulatory regions of the vascular endothelial growth factor (VEGF) gene in female patients with rheumatoid arthritis (RA).

SUBJECTS AND METHODS

The investigation enrolled 257 female patients with RA. A control group consisted of 297 women without chronic diseases. The investigators examined the single-nucleotide polymorphism of VEGF-А2578С in the promoter region (rs699947) and that of VEGF+С936Т 3 in the retranslated region (rs3025039) of the gene. Genotyping was performed by restriction fragment length polymorphism analysis.

RESULTS

There was an increase in the frequency of VEGF+936 CT and a reduction in that of the VEGF+936СС genotypes in the seronegative patients as compared to the healthy women. The VEGF+936СС genotype frequency was higher in the patients with seropositive RA than in the subgroup of seronegative patients. The frequency of the VEGF-2578СС genotype was increased in the patients with RA and rheumatoid nodules, as compared to the healthy women.

CONCLUSION

The data presented suggest that the presence of certain VEGF gene variants located in the regulatory regions may reflect the nature of immunopathological mechanisms in RA.

Analysis of VEGFA Variants and Changes in VEGF Levels Underscores the Contribution of VEGF to Polycystic Ovary Syndrome

Background

Vascular endothelial growth factor (VEGF) contributes to the pathogenesis of polycystic ovary syndrome (PCOS), and genetic variations in VEGFA gene were suggested to contribute to VEGF secretion and PCOS.

Aim

To evaluate the association of altered VEGF levels, stemming from the presence of specific VEGFA variants, with altered risk of PCOS.

Subjects and Methods

Retrospective case-control study, performed between 2012–2015. Study subjects comprised 382 women with PCOS, and 393 control subjects. ELISA measured VEGF levels; genotyping of VEGFA variants was done by allelic exclusion.

Results

Among the 12 tested VEGFA SNPs, minor allele frequency of only rs3025020 was significantly higher in PCOS cases than control women. Increased and reduced PCOS risk was seen with rs3025020 and rs2010963 genotypes, respectively. Increases and reduction in VEGF levels were associated with rs3025020 and rs2010963, respectively. Increased fasting insulin and HOMA-IR, and bioactive testosterone were linked with rs3025020, while carriage of rs2010963 was linked with reduction in fasting insulin, and free and bioactive testosterone. Of the 12 VEGFA variants, 9 were in LD, thus allowing construction of 9-locus haplotypes. Increased frequency of CAACAGCGA haplotype was seen in PCOS cases, after controlling for BMI, free and bioactive testosterone, SHBG, free insulin and HOMA-IR.

Conclusion

This study confirms the contribution of altered VEGF secretion, resulting from genetic variation in VEGFA gene into the pathogenesis of PCOS. This supports a role for VEGF as PCOS candidate locus.

VEGF-A and VEGFR1 SNPs associate with preeclampsia in a Philippine population

The vascular endothelial growth factor (VEGF) family is important for establishing normal pregnancy, and related single nucleotide polymorphisms (SNPs) are implicated in abnormal placentation and preeclampsia. We evaluated the association between preeclampsia and several VEGF SNPs among Filipinos, an ethnically distinct group with high prevalence of preeclampsia. The genotypes and allelic variants were determined in a case-control study (191 controls and 165 preeclampsia patients) through SNP analysis of VEGF-A (rs2010963, rs3025039) and VEGF-C (rs7664413) and their corresponding receptors VEGFR1 (rs722503, rs12584067, rs7335588) and VEGFR3 (rs307826) from venous blood DNA. VEGF-A rs3025039 C allele has been shown to associate with preeclampsia (odds ratio of 1.648 (1.03-2.62)), while the T allele bestowed an additive effect for the maintenance of normal, uncomplicated pregnancy and against the development of preeclampsia (odds ratio of 0.62 (0.39-0.98)). VEGFR1 rs722503 is associated with preeclampsia occurring at or after the age of 40 years. The results showed that genetic variability of VEGF-A and VEGFR1 are important in the etiology of preeclampsia among Filipinos.

Association of VEGFA gene polymorphisms and VEGFA plasma levels with spontaneous preterm birth

BACKGROUND

Angiogenic pathway regulating genes such as vascular endothelial growth factor A (VEGFA) have been implicated in preterm birth (PTB) complications. Research shows that the VEGFA/VEGF receptor system plays an important role in the regulation of circulating progesterone level. Attenuation of VEGFA signaling at mid pregnancy results in onset of labor and parturition because of a reduction in circulating progesterone levels. The aim of this study was to investigate the association of VEGFA gene polymorphisms (rs2010963, rs3025039, rs699947, and rs10434) with spontaneous PTB and VEGFA plasma levels in preterm and term women.

STUDY DESIGN

Peripheral maternal blood from 495 women was used for extraction of DNA and genotyping was carried out using the SequenomMassARRAY platform. Maternal plasma was used to measure VEGFA levels.

RESULTS

Results showed a significant association between rs2010963 variants and PTB at both allelic and genotypic levels. The frequencies of CG and GG genotypes were significantly higher in the preterm group (96%) than in the term group (87%) (P=0.012). The odds of the G allele occurring among the preterm group was 1.8 times higher than those in the term group (odds ratio 1.8, 95% confidence interval 1.2-2.6, P=0.003). After adjustment for Bonferroni correction, the association between rs2010963 variants and PTB remained significant (P=0.004). The rs69947 was associated with PTB at a nominal significance level (P=0.030). There was no significant association between rs3025039, rs10434, and PTB in this population. VEGFA gene polymorphisms were not associated with VEGFA plasma levels. This study indicated for the first time that the VEGFA rs2010963 polymorphisms may play a potential role in preterm complications.

Vascular endothelial growth factor (VEGF)-634G/C polymorphism was associated with severe pre-eclampsia and lower serum VEGF level

AIM

Vascular endothelial growth factor (VEGF) is an angiogenic factor whose production is increased in pre-eclampsia (PE). Therefore, the present study was conducted aiming at assessing the possible association of VEGF polymorphisms with PE susceptibility in the southeast of Iran.

MATERIAL AND METHODS

Overall, 192 PE women and 186 unrelated age-matched normotensive pregnant women were genotyped for the VEGF-2578C/A (rs699947), -1154G/A (rs1570360), and -634G/C (rs2010963) polymorphisms using the polymerase chain reaction-restriction fragment length polymorphism method. Serum VEGF levels were determined by the enzyme-linked immunosorbent assay method.

RESULTS

There was no significant difference in VEGF-2578C/A, -1154G/A and -634G/C polymorphisms between PE women and controls. However, the frequency of VEGF-634GC and CC genotypes was significantly higher in women with severe PE compared to mild PE and controls. In addition, serum VEGF levels were significantly lower in PE women. The VEGF-634CC genotype was associated with lower serum VEGF levels compared to the VEGF-634GG genotype. Moreover, serum VEGF levels were significantly lower in individuals with the VEGF-634CC genotype compared to VEGF-634GC genotype only in the control group. The mean serum VEGF levels did not differ significantly between genotypes of VEGF-2587C/A and -1154G/A polymorphisms.

CONCLUSION

Our findings suggest that the association of VEGF-634G/C polymorphisms with severe PE and the VEGF-634CC genotype was correlated with lower serum VEGF levels.

Preeclampsia and the Anti-Angiogenic State

Preeclampsia is a major cause of maternal and fetal morbidity and mortality worldwide, however, its etiology remains unclear. Abnormal placental angiogenesis during pregnancy resulting from high levels of anti-angiogenic factors, soluble Flt1 (sFlt1) and soluble endoglin (sEng), has been implicated in preeclampsia pathogenesis. Accumulating evidence also points to a role for these anti-angiogenic proteins as serum biomarkers for the clinical diagnosis and prediction of preeclampsia. Uncovering the mechanisms of altered angiogenic factors in preeclampsia may also provide insights into novel preventive and therapeutic options.

Polymorphisms in VEGFA gene affect the antihypertensive responses to enalapril

PURPOSE

Vascular endothelial growth factor (VEGF) is a potent angiogenic factor that affects blood pressure by promoting vasodilation mediated by nitric oxide. Angiotensin-converting enzyme inhibitors (ACEi) up-regulate the VEGF expression; thus, genetic polymorphisms in the VEGFA gene could affect the antihypertensive responses to these drugs.

METHODS

Hypertensive patients (n = 102) were prospectively treated only with the ACEi enalapril for 60 days. We compared the effect of VEGFA polymorphisms on changes in blood pressure after enalapril treatment. In addition, multiple linear regression analysis was carried out to assess the effect of covariates on blood pressure. Genotypes for g.-2578C>A (rs699947), g.-1154G>A (rs1570360), and g.-634G>C (rs2010963) VEGFA polymorphisms were determined, and haplotype frequencies were estimated.

RESULTS

Individuals carrying the CA and AA genotypes for the g.-2578C>A polymorphism and the AGG haplotype showed more intense decrease in blood pressure in response to enalapril 20 mg/day. A multiple linear regression analysis showed that the AA genotype for the g.-2578C>A polymorphism and the AGG haplotype are associated with more intense decrease in blood pressure in response to enalapril 20 mg/day, while the CC genotype for the g.-2578C>A polymorphism and the CGG haplotype are associated with the opposite effect.

CONCLUSIONS

These findings suggest that polymorphisms in VEGFA gene may affect the antihypertensive responses to enalapril.

Associations between Individual and Combined Polymorphisms of the TNF and VEGF Genes and the Embryo Implantation Rate in Patients Undergoing In Vitro Fertilization (IVF) Programs

BACKGROUND

A multiple pregnancy is now considered to be the most common adverse outcome associated with in vitro fertilization (IVF). As a consequence, the identification of women with the best chances of embryo implantation is a challenge in IVF program, in which the objective is to offer elective single-embryo transfer (eSET) without decreasing the pregnancy rate. To date, a range of hormonal and clinical parameters have been used to optimize eSET but none have significant predictive value. This variability could be due to genetic predispositions related to single-nucleotide polymorphisms (SNPs). Here, we assessed the individual and combined impacts of thirteen SNPs that reportedly influence the outcome of in vitro fertilisation (IVF) on the embryo implantation rate for patients undergoing intracytoplasmic sperm injection program (ICSI).

MATERIALS AND METHODS

A 13 gene polymorphisms: FSHR(Asn680Ser), p53(Arg72Pro), AMH(Ile49Ser), ESR2(+1730G>A), ESR1(-397T>C), BMP15(-9C>G), MTHFR1(677C>T), MTHFR2(1298A>C), HLA-G(-725C>G), VEGF(+405G>C), TNFα(-308A>G), AMHR(-482A>G), PAI-1(4G/5G), multiplex PCR assay was designed to genotype women undergoing ICSI program. We analyzed the total patients population (n = 428) and a subgroup with homogeneous characteristics (n = 112).

RESULTS

Only the VEGF(+405G>C) and TNFα(-308A>G) polymorphisms impacted fertilization, embryo implantation and pregnancy rates. Moreover, the combined VEGF+405.GG and TNFα-308.AG or AA genotype occurred significantly more frequently in women with high implantation potential. In contrast, the VEGF+405.CC and TNFα-308.GG combination was associated with a low implantation rate.

CONCLUSION

We identified associations between VEGF(+405G>C) and TNFα(-308A>G) polymorphisms (when considered singly or as combinations) and the embryo implantation rate. These associations may be predictive of embryo implantation and could help to define populations in which elective single-embryo transfer should be recommended (or, conversely, ruled out). However, the mechanism underlying the function of these polymorphisms in embryo implantation remains to be determined and the associations observed here must be confirmed in a larger, more heterogeneous cohort.

Vascular endothelial growth factor +936C/T, -634G/C, -2578C/A, and -1154G/A polymorphisms with risk of preeclampsia: a meta-analysis

BACKGROUND

Emerging evidence showed that VEGF gene polymorphisms are involved in the regulation of VEGF protein expression, thus increasing an individual's susceptibility to preeclampsia (PE); but individually published results are inconclusive. The aim of this meta-analysis was to investigate the associations between VEGF gene polymorphisms and PE risk.

METHODS

A systematic literature search of MEDLINE, Embase, Web of Science, and CNKI (Chinese National Knowledge Infrastructure) databases was conducted. Statistical analyses were performed using STATA 12.0 software and Review manager 5.1. Odds ratios (ORs) with 95% confidence intervals (CIs) were used to assess the strength of associations.

RESULTS

According to the inclusion criteria, 11 case-control studies were finally included in this meta-analysis. A total of 1,069 PE cases and 1,315 controls were included in this study. Our meta-analysis indicated that VEGF +936C/T (T vs. C, OR = 1.52, 95%CI = 1.08-2.12) or -634G/C polymorphism (C vs. G, OR = 1.24, 95% CI = 1.03-1.50) was associated with the risk of PE, whereas there was no association between -2578C/A (A vs. C, OR = 0.98, 95%CI = 0.82-1.16) or -1154G/A (A vs. G, OR = 1.30, 95%CI = 0.94-1.78) polymorphism and PE risk in our study.

CONCLUSION

Our meta-analysis suggested that VEGF -2578C/A or -1154G/A polymorphism had no association with PE risk in all examined patients, whereas there was an association between VEGF +936C/T or -634G/C polymorphism and risk of PE.

Associations between vascular endothelial growth factor gene polymorphisms and pre-eclampsia susceptibility: a meta-analysis

OBJECTIVE

The aim of this study was to assess whether vascular endothelial growth factor (VEGF) polymorphisms are associated with susceptibility to pre-eclampsia.

METHODS

A meta-analysis was conducted on the associations between the -634 C/G, +936 C/T, -1154 A/G, and -2578 A/C polymorphisms of VEGF and pre-eclampsia.

RESULTS

Ten studies involving 2068 subjects (pre-eclampsia, 950; controls, 1118) were included in the meta-analysis. The meta-analysis revealed an association between pre-eclampsia and the VEGF -634 C allele in overall group (OR = 1.351, 95% CI = 1.105-1.651, p = 0.003) and in European group (OR = 1.427, 95% CI = 1.139-1.787, p = 0.002). The meta-analysis revealed an association between pre-eclampsia and the VEGF -936 T allele in Asians, but not in Europeans (OR = 1.555, 95% CI = 1.232-1.961, p = 1.9 × 10(-5); OR = 1.587, 95% CI = 0.933-2.699, p = 0.088). However, the meta-analysis revealed no association between pre-eclampsia and the VEGF -1154 A/G and 2578 A/C polymorphisms

CONCLUSIONS

This meta-analysis suggested that the VEGF -634 C/G polymorphism is associated with susceptibility to pre-eclampsia in Europeans and that the VEGF -634 C/G polymorphism is associated with pre-eclampsia in Asians.

Crude bark extract of Dysozylum alliarium induces alteration in histological structures and VEGF-C expression in uterus during days 4-7 of gestation in albino rat

PURPOSE

Crude bark extract (CBE) of Dysoxylum alliarium was tested in vivo for its effects on rat uterus during estrus and day 4-7 of gestation. The purpose is to study the effects of CBE on embryo implantation and VEGF-C expression during peri-implantation period to find out possible role of VEGF-C and embryo implantation.

METHODS

Threshold was determined by multiple-dose administration of CBE. CBE prepared in methanol was orally administered in a dose of 500 mg/kg/day to female rats during day 1-7 of gestation. Routine H&E histology of uteri was studied during estrus phase and days 4-7 of gestation. The vascular endothelial growth factor (VEGF-C) was studied immunohistochemically and via western blot using VEGF-C antibody.

RESULTS

The crude bark extract induced the structural aberration of uterine histology in cyclic stage and during peri-implantation. Cellular degeneration of embryo and supporting maternal tissue caused loss of embryo minimizing the litter size. Expression of VEGF-C was drastically reduced in the CBE treated females' uteri than that of the controls.

CONCLUSIONS

CBE contains potential compounds capable of fertility control as post-coital contraceptive. Effects of CBE on embryo and foetal-maternal interface either mediated through reduced VEGF-C expression or vice versa.

Vascular endothelial growth factor family gene polymorphisms in preeclampsia in Sinhalese women in Sri-Lanka

OBJECTIVE

To investigate the association of polymorphisms in the vascular endothelial growth factor (VEGF) family genes (VEGFA rs699947, VEGFA rs3025039, PGF rs1042886, KDR rs2071559 and KDR rs2305948) with preeclampsia in Sinhalese women in Sri-Lanka.

METHODS

We conducted a case-control study where 175 nulliparous Sinhalese women with preeclampsia and 171 normotensive women matched for age, ethnicity, parity and BMI were recruited in tertiary care maternity hospitals in Sri-Lanka. Preeclampsia was diagnosed using international guidelines. DNA extracted from peripheral venous blood and was genotyped using the Sequenom MassARRAY system. χ(2)-test was used to compare the distribution of allele and genotype frequencies between the cases and the control subjects.

RESULTS

The frequency of PGF rs1042886 variant allele (odds ratio (OR) 1.5, 95% confidence interval (CI) 1.1-2.1) and dominant genotype model (aOR 1.6, 95% CI 1.0-2.4) were increased in preeclamptic women compared to controls. VEGFA rs699947, VEGFA rs3025039, KDR rs2071559, and KDR rs2305948 polymorphisms were not associated with preeclampsia.

CONCLUSION

Maternal PGF rs1042886 polymorphism is associated with preeclampsia in Sinhalese women in Sri-Lanka.

Increased risk of ovarian hyperstimulation syndrome following controlled ovarian hyperstimulation in patients with vascular endothelial growth factor +405 cc genotype

Ovarian hyperstimulation syndrome (OHSS) is a serious complication following controlled ovarian hyperstimulation (COH) for in vitro fertilization. OHSS has a range of clinical features from mild abdominal distention to severe thromboembolic events. Several clinical manifestations of OHSS such as ascites and hemoconcentration can be attributed to increased vascular permeability. Vascular endothelial growth factor (VEGF) and its receptor VEGFR2 have been identified as an important signaling system in mediating this increase. There is considerable genetic variation in the VEGF/R2 signaling system. We present the first study to examine if single nucleotide polymorphisms (SNPs) in the genes encoding the VEGF/R2 signaling system are associated with OHSS following COH. Blood samples from 53 OHSS patients and 100 controls were analyzed for six SNPs of interest. Odds ratios (OR) and 95% confidence intervals (95% CI) were estimated by a multivariate logistic regression model. We found an association between the VEGF +405cc genotype and OHSS (OR 3.4, 95% CI 1.01-11.7). This finding requires confirmation from other patient populations.

The vascular endothelial growth factor (VEGF) +405 G/C polymorphism and its relationship with recurrent implantation failure in women in an IVF programme with ICSI

PURPOSE

Successful embryo implantation depends on trophoblast proliferation, migration and, lastly, invasion of the endometrium (to anchor the trophoblast to the uterus). This invasion is mediated by locally produced soluble factors. Of these, vascular endothelial growth factor (VEGF) is the best characterized regulator of angiogenesis. Here, we investigate the association between the VEGF + 405 C/G genotype and the recurrence of embryo implantation failure in women undergoing in vitro fertilization (IVF) program with intracytoplasmic sperm injection (ICSI).

METHODS

Forty women with recurrent implantation failure defined by absence of pregnancy after transfer of more than 10 embryos and 131 women control, with at least one live birth after the transfer of fewer than 10 embryos were included. Genomic DNA was analysed with an allele-specific polymerase chain reaction and a Chi-2 test was used to compare the respective VEGF + 405 C/G genotype frequencies in cases and controls.

RESULTS

The frequency of the VEGF +405C/C genotype was higher in women with recurrent implantation failure after ICSI-embryo transfer than in controls (17.5 % and 5.3 %, respectively, p = 0.01).

CONCLUSION

The VEGF +405 G/C polymorphism may influence embryo implantation and VEGF + 405 C/C genotype may predispose to recurrent implantation failure after ICSI-ET.

Feto-placental nitric oxide, asymmetric dimethylarginine and vascular endothelial growth factor (VEGF) levels and VEGF gene polymorphisms in severe preeclampsia

OBJECTIVE

To measure plasma nitric oxide (NO), asymmetric dimethylarginine (ADMA) and vascular endothelial growth factor (VEGF) levels and VEGF gene polymorphisms in fetal circulation in severe preeclampsia.

METHODS

Cord vessels of singleton gestations complicated with severe preeclampsia 36 weeks or more (n = 31) and controls were sampled upon delivery for analyte measuring. Additionally, DNA was extracted from umbilical vein whole blood to determine the frequency of VEGF gene single nucleotide polymorphisms (SNPs): -2578 A/C, -1498 C/T, -1154 A/G, -634 C/G and +936 C/T. Coefficient correlations between analyte levels and placental and neonatal weight were calculated.

RESULTS

NO plasma levels in umbilical vessels (artery and vein) were significantly higher in preeclampsia cases as compared to controls (4.67 ± 3.0 vs. 0.82 ± 0.90; 4.46 ± 3.0 vs. 0.82 ± 0.99 mmol/L, respectively, p = 0.0001 both). ADMA levels displayed a similar increased trend in both fetal vessels, but this did not reach statistical significance (2.57 ± 1.03 vs. 2.34 ± 0.57; 2.74 ± 0.94 vs. 2.42 ± 0.59 mmol/L, respectively, p > 0.05). VEGF was significantly lower in artery but not in vein in preeclampsia cases (200.48 ± 225.62 vs. 338.61 ± 287.03 pg/mL, p = 0.04). A significant positive correlation was found between NO and ADMA levels (artery and vein) among preeclampsia cases. Overall, the frequency of the studied VEGF gene SNPs did not differ among pre-eclamptic cases and controls; nevertheless, a significant trend toward lower umbilical vein VEGF levels was observed in pre-eclampsia cases in the presence of -2578 CC and -1154 AG genotypes.

CONCLUSION

Near term gestations complicated with severe preeclampsia presented higher NO levels in fetal circulation, which correlated to ADMA and lower artery VEGF values. More research is warranted to confirm that selected VEGF SNPs may be associated with lower umbilical vein VEGF.

The vascular endothelial growth factor family in adverse pregnancy outcomes

BACKGROUND

Pre-eclampsia, small-for-gestational-age infants, preterm birth and recurrent miscarriage complicate a significant number of pregnancies. The vascular endothelial growth factor (VEGF) family of angiogenic growth factors is implicated in the pathophysiology of these complications. We aimed to elucidate the role of these angiogenic factors in placentation and to evaluate the predictive value of their protein concentrations and genetic variations in pregnancy complications.

METHODS

We performed a systematic search of PubMed, and retrieved original articles. The search included a combination of terms such as VEGF-A, placental growth factor (PlGF), kinase insert domain receptor, fms-like-tyrosine-kinase receptor 1, soluble fms-like-tyrosine-kinase receptor 1, pre-eclampsia, small-for-gestational-age infants, preterm birth, recurrent miscarriage, placenta, prediction and polymorphisms.

RESULTS

This review summarizes the current knowledge of the roles of the VEGF family in early placentation and of the abnormalities in maternal plasma and placental expression of angiogenic proteins in adverse pregnancy outcomes compared with normal pregnancy. PlGF and sFLT-1 in combination with other clinical and biochemical markers in late first or second trimester appear to predict early-onset pre-eclampsia with a high sensitivity and specificity. However, VEGF family proteins do not have sufficient power to accurately predict late-onset pre-eclampsia, small-for-gestational age pregnancies or preterm birth. Functional polymorphisms in these angiogenic genes are implicated in pregnancy complications, but their contribution appears to be minor.

CONCLUSIONS

Although the VEGF family has important roles in normal and complicated pregnancy, the current predictive value of the VEGF family as biomarkers appears to be limited to early-onset pre-eclampsia.

Vascular endothelial growth factor gene polymorphisms in spontaneously aborted fetuses

PROBLEMS

The VEGF-1154G>A polymorphism has been reported to be a genetic risk factor for recurrent spontaneous abortion in various studies; however, these studies have focused on genetic analyses of pregnant women rather than aborted fetuses. To evaluate and confirm the association between the VEGF-1154G>A polymorphism and spontaneous abortion, we focused on the relationship between four polymorphisms in the VEGF gene (-2578C>A, -1154G>A, -634G>C, and 936C>T) and spontaneously aborted fetuses (SAFs).

METHOD OF STUDY

The subjects included 118 SAFs at <20 weeks gestation and 380 normal controls consisting of children and adults. The polymorphisms were genotyped by polymerase chain reaction-restriction fragment length polymorphism analysis.

RESULTS

Spontaneously aborted fetuses exhibited significantly different frequencies of the -2578CA+AA/-634CC and -1154GA+AA/-634CC combined genotypes compared with control subjects. The frequency of the -2578A/-1154A/-634C/936C haplotype was significantly higher in SAFs.

CONCLUSIONS

VEGF genes -2578CA+AA/-634CC and -1154GA+AA/-634CC in the fetus are possible risk factors for spontaneous abortion.

No association between polymorphisms/haplotypes of the vascular endothelial growth factor gene and preeclampsia

BACKGROUND

Preeclampsia (PE) is the first worldwide cause of death in pregnant women, intra-uterine growth retardation, and fetal prematurity. Some vascular endothelial grown factor gene (VEGF) polymorphisms have been associated to PE and other pregnancy disturbances. We evaluated the associations between VEGF genotypes/haplotypes and PE in Mexican women.

METHODS

164 pregnant women were enrolled in a case-control study (78 cases and 86 normotensive pregnant controls). The rs699947 (-2578C/A), rs1570360 (-1154G/A), rs2010963 (+405G/C), and rs25648 (-7C/T), VEGF variants were discriminated using Polymerase Chain Reaction - Restriction Fragment Length Polymorphism (PCR-RFLP) methods or Taqman single nucleotide polymorphism (SNP) assays.

RESULTS

The proportions of the minor allele for rs699947, rs1570360, rs2010963, and rs25648 VEGF SNPs were 0.33, 0.2, 0.39, and 0.17 in controls, and 0.39, 0.23, 0.41, and 0.15 in cases, respectively (P values > 0.05). The most frequent haplotypes of rs699947, rs1570360, rs2010963, and rs25648 VEGF SNPs, were C-G-C-C and C-G-G-C with frequencies of 0.39, 0.21 in cases and 0.37, 0.25 in controls, respectively (P values > 0.05)

CONCLUSION

There was no evidence of an association between VEGF alleles, genotypes, or haplotypes frequencies and PE in our study.

Decreased proportion of peripheral blood vascular endothelial growth factor-expressing T and natural killer cells in preeclampsia

OBJECTIVE

The purpose of this study was to determine the proportion of circulating T and natural killer (NK) cells that express intracellular vascular endothelial growth factor (VEGF) in women with preeclampsia compared to those with a normal pregnancy.

STUDY DESIGN

In all, 24 preeclamptic patients and 30 healthy pregnant women were involved in this case-control study. Intracellular VEGF expression of unstimulated lymphocytes was determined with flow cytometric examination.

RESULTS

In healthy pregnant women, the majority of both T and NK cells expressed VEGF in their cytoplasma (median, 79.9%; 25-75 percentile, 73.7-87.0 and median, 78.3%; 25-75 percentile, 64.1-85.3, respectively). Furthermore, CD4(+) helper and CD8(+) cytotoxic T cells showed a similar pattern of VEGF expression in normal pregnancy. However, the proportion of VEGF-expressing peripheral blood T (both helper and cytotoxic) and NK cells was markedly decreased in preeclampsia (for T cells: median, 51.6%; 25-75 percentile, 40.1-60.0; P < .001; for NK cells: median, 45.2%; 25-75 percentile, 27.4-64.0; P < .001).

CONCLUSION

Our results suggest decreased production of VEGF by circulating T and NK cells in preeclampsia, which might contribute to the development of the generalized endothelial dysfunction characteristic of the maternal syndrome of the disease.

The role of vascular endothelial growth factor genetic variability in cancer

Angiogenesis is a hallmark of tumor pathogenesis. Vascular endothelial growth factor (VEGF) is a critical regulator of angiogenesis and its inhibition has become a successful approach to antitumor therapy across tumor types. The VEGF gene is highly polymorphic with multiple common single nucleotide polymorphisms (SNPs) in the promoter, 5' untranslated region and 3' untranslated region. There is evidence that these SNPs in the regulatory regions can affect VEGF expression. In vitro and in vivo data show that genetic variability affects the activity and expression of VEGF. Case-control and cohort studies suggest that genetic variability may affect risk and outcome of a variety of disease states that are tightly regulated by angiogenesis. Recently, genetic variability in VEGF has been studied as a potential predictive biomarker for bevacizumab. The VEGF-1154 AA and -2578 AA genotypes predicted an improved median overall survival, whereas the VEGF-634 CC and -1498 TT genotypes predicted protection from grade 3-4 hypertension in the pivotal trial, E2100. If validated, these finding could help direct which subgroup of patients should receive bevacizumab.

Vascular endothelial growth factor -2578 A/C, -460 T/C and +405 G/C polymorphisms in polycystic ovary syndrome

OBJECTIVE

Vascular endothelial growth factor (VEGF) may be involved in the physiological regulation of ovarian angiogenesis and pathogenesis of polycystic ovary syndrome (PCOS). VEGF -2578 A/C, -460 T/C and +405 G/C single nucleotide polymorphisms (SNPs) are known to be related to VEGF production.

STUDY DESIGN

In order to investigate the possible association between VEGF gene and PCOS susceptibility, we analyzed genotype and allele distributions of above mentioned SNPs in 137 patients with PCOS and 155 healthy women. Differences in genotype distributions and allele frequencies in the cases and controls were compared for statistical significance using the chi(2)-test. Haplotype frequencies were estimated using a contingency chi(2)-test. Mann-Whitney U test was used for the statistics of the clinical and biochemical parameters.

RESULTS

No significant association between PCOS and the variant alleles of VEGF -2578 (OR: 0.91, 95% CI=0.65-1.26), -460 (OR: 0.78, 95% CI=0.56-1.08), and +405 (OR: 1.25, 95% CI=0.81-1.93) was observed. However, haplotype analysis demonstrated that the frequency of CTG haplotype, was higher among PCOS compared with controls (p=0.019) and that there is a strong linkage disequilibrium (D'=0.873, r(2)=0.752) between -2578 and -460 polymorphisms.

CONCLUSIONS

These preliminary results suggest that the -2578, -460 and +405 SNPs of VEGF gene are not significant risk factors for PCOS development alone. However, because of the high VEGF producer CTG haplotype was more frequent among the PCOS, we suppose that investigated polymorphisms--interacting with other genetic and environmental factors--could play a role in the development of PCOS.

Association of VEGF polymorphisms with childhood asthma, lung function and airway responsiveness

Vascular endothelial growth factor (VEGF) is an angiogenic factor implicated in asthma severity. The objective of the present study was to determine whether VEGF single nucleotide polymorphisms (SNPs) are associated with asthma, lung function and airway responsiveness. The present authors analysed 10 SNPs in 458 white families in the Childhood Asthma Management Program (CAMP). Tests of association with asthma, lung function and airway responsiveness were performed using PBAT software (Golden Helix, Inc. Bozeman, MT, USA; available at www.goldenhelix.com). Family and population-based, revpeated measures analysis of airflow obstruction were conducted. Replication studies were performed in 412 asthmatic children and their parents from Costa Rica. Associations with asthma, lung function and airway responsiveness were observed in both cohorts. SNP rs833058 was associated with asthma in both cohorts. This SNP was also associated with increased airway responsiveness in both populations. An association of rs4711750 and its haplotype with forced expiratory volume in 1 s (FEV(1))/forced vital capacity (FVC) ratio in both cohorts was observed. Longitudinal analysis in CAMP confirmed an association of rs4711750 with FEV(1)/FVC decline over approximately 4.5 yrs of observation. VEGF polymorphisms are associated with childhood asthma, lung function and airway responsiveness in two populations, suggesting that VEGF polymorphisms influence asthma susceptibility, airflow obstruction and airways responsiveness.

Vascular endothelial growth factor genotypes and haplotypes are associated with pre-eclampsia but not with gestational hypertension

Vascular endothelial growth factor (VEGF) is relevant for normal pregnancy, and abnormalities in VEGF functions are associated with hypertensive disorders of pregnancy. Because there are few studies on how VEGF genetic polymorphisms affect susceptibility to pre-eclampsia (PE), and no studies on how they affect susceptibility to gestational hypertension (GH), we compared VEGF genotype and haplotype distributions in normotensive and hypertensive pregnancies. Genotypes and haplotypes for VEGF polymorphisms (C-2578A, G-1154A and G-634C) were determined in 303 pregnant women (108 healthy pregnant, HP; 101 with GH and 94 with PE). When white and non-white pregnant women were considered together, no significant differences were found in the distributions of VEGF genotypes or haplotypes (P > 0.05) in the three groups. However, with only white subjects, significant differences were found in genotypes distributions for two (C-2578A and G-634C) VEGF polymorphisms (both P < 0.05) between the HP and the PE groups. Importantly, the haplotype including the variants C-2578, G-1154 and C-634, which is associated with higher VEGF gene expression, was less common in the PE group compared with the HP group (4% versus 16%; P = 0.0047). However, we found no significant differences in VEGF haplotypes distributions when the HP and GH groups were compared (P > 0.05). These findings suggest a protective effect for the 'C-2578, G-1154 and C-634' haplotype against the development of PE, but no major effects of VEGF gene variants on susceptibility to GH.

Association of vascular endothelial growth factor and vascular endothelial growth factor receptor-2 genetic polymorphisms with outcome in a trial of paclitaxel compared with paclitaxel plus bevacizumab in advanced breast cancer: ECOG 2100

PURPOSE

No biomarkers have been identified to predict outcome with the use of an antiangiogenesis agent for cancer. Vascular endothelial growth factor (VEGF) genetic variability has been associated with altered risk of breast cancer and variable promoter activity. Therefore, we evaluated the association of VEGF genotype with efficacy and toxicity in E2100, a phase III study comparing paclitaxel versus paclitaxel plus bevacizumab as initial chemotherapy for metastatic breast cancer.

PATIENTS AND METHODS

DNA was extracted from tumor blocks of patients from E2100. Three hundred sixty-three samples were available to evaluate associations between genotype and outcome. Genotyping was performed for selected polymorphisms in VEGF and VEGF receptor 2. Testing for associations between each polymorphism and efficacy and toxicity was performed.

RESULTS

The VEGF-2578 AA genotype was associated with a superior median overall survival (OS) in the combination arm when compared with the alternate genotypes combined (hazard ratio = 0.58; 95% CI, 0.36 to 0.93; P = .023). The VEGF-1154 A allele also demonstrated a superior median OS with an additive effect of each active allele in the combination arm but not the control arm (hazard ratio = 0.62; 95% CI, 0.46 to 0.83; P = .001). Two additional genotypes, VEGF-634 CC and VEGF-1498 TT, were associated with significantly less grade 3 or 4 hypertension in the combination arm when compared with the alternate genotypes combined (P = .005 and P = .022, respectively).

CONCLUSION

Our data support an association between VEGF genotype and median OS as well as grade 3 or 4 hypertension when using bevacizumab in metastatic breast cancer.

No association of the genetic polymorphisms of endothelial nitric oxide synthase, dimethylarginine dimethylaminohydrolase, and vascular endothelial growth factor with preeclampsia in Korean populations

The purpose of this study was to investigate whether there is any association between preeclampsia and eNOS, DDAH, and VEGF gene polymorphisms, and also to search for a possible association between haplotypes in eNOS, DDHA, and VEGF genes and the risk for preeclampsia. DNA was extracted from whole blood of 223 preeclampsia patients and 237 healthy pregnant women. The genotypes were analyzed by a single base primer extension assay using a SNaPShot assay kit. Results were analyzed with the Student's t-test, Chi-square test, and Logistic regression analysis. Haplotype analyses were performed using Haploview 3.2 version. There were no significant differences in genotype or allele frequencies of eNOS, DDAH, and VEGF gene polymorphisms between preeclampsia patients and controls. No increase in the risk of preeclampsia for those genes was observed under any model of inheritance and there were no statistically significant associations between any haplotypes and preeclampsia risk. Polymorphisms in eNOS, DDAH, and VEGF gene do not seem to be risk factors for preeclampsia.

Genes and the preeclampsia syndrome

Preeclampsia is specific to pregnancy and is still a leading cause of maternal and perinatal mortality and morbidity, affecting about 3% of women, but the underlying pathogenetic mechanisms still remain unclear. Immune maladaptation, placental ischemia and increased oxidative stress represent the main components discussed to be of etiologic importance, and they all may have genetic implications. Since the familial nature of preeclampsia is known for many years, extensive research on the genetic contribution to the pathogenesis of this severe pregnancy disorder has been performed. In this review, we will overview the linkage and candidate gene studies carried out so far as well as summarize important historical notes on the genetic hypotheses generated in preeclampsia research. Moreover, the influence of maternal and fetal genes and their interaction as well as the role of genomic imprinting in preeclampsia will be discussed.

Vascular endothelial growth factor gene polymorphisms and recurrent pregnancy loss

PROBLEM

To be successful, pregnancy must induce its own blood supply through angiogenesis and vascular endothelial growth factor (VEGF) is the best characterized regulator of angiogenesis and one polymorphism of the VEGF gene, -1154, has been suggested to be associated with recurrent spontaneous abortion. The aim of this study was to confirm or refute the relationship of VEGF -1154 to recurrent pregnancy loss (RPL).

METHOD OF STUDY

Buccal swabs were obtained from 152 women with history of two or more consecutive spontaneous abortions and 65 control women. DNA was extracted from the buccal swabs and analyzed for the presence of the VEGF -1154A/A gene.

RESULTS

The frequency of homozygosity of the VEGF -1154A gene was significantly higher among women experiencing RPL compared with fertile control women (16% versus 6%, P < 0.05).

CONCLUSION

Homozygosity of the VEGF -1154A gene may serve as a susceptibility factor affecting for RPL.