VEGF 936C>T polymorphism and breast cancer risk: evidence from 5,729 cases and 5,868 controls

Association between VEGF genetic variants and diabetic foot ulcer in Chinese Han population: A case-control study

The aim of this study was to investigate the association of vascular endothelial growth factor (VEGF) gene polymorphisms with diabetic foot ulcer (DFU) susceptibility in a Chinese Han population.Around 88 type 2 diabetes mellitus (T2DM) patients without DFU and 97 T2DM patients with DFU were enrolled in this study. A total of 103 age and gender matched healthy individuals were recruited as healthy control. VEGF gene polymorphisms rs699947 and rs13207351 were analyzed by polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP) method. Odds ratio (OR) with 95% confidence interval (CI) was calculated to assess the association between VEGF gene polymorphisms and DFU risk.The frequency of AA and AC genotypes of rs699947 were lower in DFU patients than that in healthy controls (P = .020, P = .031), suggesting that AC and AA genotypes were negatively associated with DFU risk originating from healthy individuals (OR = 0.496, 95%CI = 0.274-0.899; OR = 0.130, 95%CI = 0.015-1.112). Significantly decreased trend of rs699947 A allele was observed in DFU patients when compared to the controls (P = .004), suggesting A allele was distinctly correlated with decreased DFU risk (OR = 0.490, 95%CI = 0.298-0.804). But no significant differences were detected in rs13207351 genotype and allele distributions between patients and control groups (P > .05).Individuals carrying VEGF rs699947 A allele show low susceptibility to DFU in the Chinese Han population.

The Association Between VEGF +936C/T and -634G/C Polymorphisms and Breast Cancer Susceptibility, Tumor Growth, and Metastases: Evidence From 20,728 Subjects

The relation between the polymorphisms of vascular endothelial growth factor (VEGF) and breast cancer remains inconclusive. In our meta-analysis based on 10,340 breast cancer patients and 10,388 controls, we found breast cancer susceptibility was elevated in individuals carrying the VEGF +936C allele, especially in Asians, and the +936CC increases tumor growth. The G allele of -634G/C polymorphism reduces breast cancer susceptibility in Asians, and breast cancer patients of -634GG genotype has decreased tumor growth. These results suggest that both the VEGF +936C/T and -634G/C polymorphisms influence breast cancer susceptibility and tumor growth, instead of metastasis.

Prognostic and predictive role of vascular endothelial growth factor polymorphisms in breast cancer

Current evidence indicates that angiogenesis plays an important role in the pathogenesis of several malignancies, including breast cancer. The vascular endothelial growth factor (VEGF) pathway has been investigated extensively, due to its important role in angiogenesis. The major mediator of tumor angiogenesis is VEGF-A, frequently referred to as VEGF, which activates the VEGF receptor-2. The VEGF gene is located on chromosome 6 and constitutes a highly polymorphic gene. Numerous SNPs in the promoter, 5′- and 3′-untranslated regions (UTR) of VEGF gene have been recognized. This genetic variability possibly influences the production and function of VEGF. Subsequently, the VEGF SNPs may have an impact on breast cancer risk and disease outcome. Moreover, these SNPs may be of predictive value in patients receiving agents targeting the VEGF pathway. This review presents an update on the potential role of VEGF SNPs as prognostic and/or predictive markers in patients with breast cancer.

Ethnic background and genetic variation in the evaluation of cancer risk: a systematic review

The clinical use of genetic variation in the evaluation of cancer risk is expanding, and thus understanding how determinants of cancer susceptibility identified in one population can be applied to another is of growing importance. However there is considerable debate on the relevance of ethnic background in clinical genetics, reflecting both the significance and complexity of genetic heritage. We address this via a systematic review of reported associations with cancer risk for 82 markers in 68 studies across six different cancer types, comparing association results between ethnic groups and examining linkage disequilibrium between risk alleles and nearby genetic loci. We find that the relevance of ethnic background depends on the question. If asked whether the association of variants with disease risk is conserved across ethnic boundaries, we find that the answer is yes, the majority of markers show insignificant variability in association with cancer risk across ethnic groups. However if the question is whether a significant association between a variant and cancer risk is likely to reproduce, the answer is no, most markers do not validate in an ethnic group other than the discovery cohort's ancestry. This lack of reproducibility is not attributable to studies being inadequately populated due to low allele frequency in other ethnic groups. Instead, differences in local genomic structure between ethnic groups are associated with the strength of association with cancer risk and therefore confound interpretation of the implied physiologic association tracked by the disease allele. This suggest that a biological association for cancer risk alleles may be broadly consistent across ethnic boundaries, but reproduction of a clinical study in another ethnic group is uncommon, in part due to confounding genomic architecture. As clinical studies are increasingly performed globally this has important implications for how cancer risk stratifiers should be studied and employed.

Vascular endothelial growth factor (VEGF) gene polymorphisms and breast cancer risk in a Chinese population

Vascular endothelial growth factor (VEGF) is a potent regulator of angiogenesis and thereby involved in the development and progression of solid tumours. Associations between three VEGF gene polymorphisms (-634 G/C, +936 C/T, and +1612 G/A) and breast cancer risk have been extensively studied, but the currently available results are inconclusive. Our aim was to investigate associations between three VEGF gene polymorphisms and breast cancer risk in Chinese Han patients. We performed a hospital-based case-control study including 680 female incident breast cancer patients and 680 female age-matched healthy control subjects. Polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP) analysis was performed to detect the three VEGF gene polymorphisms. We observed that women carriers of +936 TT genotypes [odds ratio (OR) =0.46, 95% confidence interval (CI) = 0.28, 0.76; P=0.002] or 936 T-allele (OR=0.81, 95% CI= 0.68, 0.98; P=0.03) had a protective effect concerning the disease. Our study suggested that the +1612G/A polymorphism was unlikely to be associated with breast cancer risk. The -634CC genotype was significantly associated with high tumor aggressiveness [large tumor size (OR=2.63, 95% CI=1.15, 6.02; P=0.02) and high histologic grade (OR=1.47, 95% CI= 1.06, 2.03; P=0.02)]. The genotypes were not related with other tumor characteristics such as regional or distant metastasis, stage at diagnosis, or estrogen or progesterone receptor status. Our study revealed that the VEGF -634 G/C and +936 C/T gene polymorphisms may be associated with breast cancer in Chinese Han patients.

Four common vascular endothelial growth factor polymorphisms (-2578C>A, -460C>T, +936C>T, and +405G>C) in susceptibility to lung cancer: a meta-analysis

BACKGROUND AND OBJECTIVE

Vascular endothelial growth factor (VEGF) is one of the key initiators and regulators of angiogenesis and it plays a vital role in the onset and development of malignancy. The association between VEGF gene polymorphisms and lung cancer risk has been extensively studied in recent years, but currently available results remain controversial or ambiguous. The aim of this meta-analysis is to investigate the associations between four common VEGF polymorphisms (i.e., -2578C>A, -460C>T, +936C>T and +405C>G) and lung cancer risk.

METHODS

A comprehensive search was conducted to identify all eligible studies to estimate the association between VEGF polymorphisms and lung cancer risk. Crude odds ratios (ORs) with 95% confidence intervals (CIs) were used to evaluate the strength of this association.

RESULTS

A total of 14 published case-control studies with 4,664 cases and 4,571 control subjects were identified. Our meta-analysis provides strong evidence that VEGF -2578C>A polymorphism is capable of increasing lung cancer susceptibility, especially among smokers and lung squamous cell carcinoma (SCC) patients. Additionally, for +936C>T polymorphism, increased lung cancer susceptibility was only observed among lung adenocarcinoma patients. In contrast, VEGF -460C>T polymorphism may be a protective factor among nonsmokers and SCC patients. Nevertheless, we did not find any association between +405C>G polymorphism and lung cancer risk, even when the groups were stratified by ethnicity, smoking status or histological type.

CONCLUSION

This meta-analysis recommends more investigations into the relationship between -2578C>A and -460C>T lung cancer risks. More detailed and well-designed studies should be conducted to identify the causal variants and the underlying mechanisms of the possible associations.

Comparative study and meta-analysis of meta-analysis studies for the correlation of genomic markers with early cancer detection

A large number of common disorders, including cancer, have complex genetic traits, with multiple genetic and environmental components contributing to susceptibility. A literature search revealed that even among several meta-analyses, there were ambiguous results and conclusions. In the current study, we conducted a thorough meta-analysis gathering the published meta-analysis studies previously reported to correlate any random effect or predictive value of genome variations in certain genes for various types of cancer. The overall analysis was initially aimed to result in associations (1) among genes which when mutated lead to different types of cancer (e.g. common metabolic pathways) and (2) between groups of genes and types of cancer. We have meta-analysed 150 meta-analysis articles which included 4,474 studies, 2,452,510 cases and 3,091,626 controls (5,544,136 individuals in total) including various racial groups and other population groups (native Americans, Latinos, Aborigines, etc.). Our results were not only consistent with previously published literature but also depicted novel correlations of genes with new cancer types. Our analysis revealed a total of 17 gene-disease pairs that are affected and generated gene/disease clusters, many of which proved to be independent of the criteria used, which suggests that these clusters are biologically meaningful.

The role of vascular endothelial growth factor a polymorphisms in breast cancer

Breast cancer is the most common cancer in females and the leading cause of cancer death in women worldwide. Angiogenesis, the formation of new blood vessels, plays an important role in the development and progression of breast cancer. Vascular endothelial growth factor A (VEGFA), the key modulator of angiogenesis, is highly expressed in cancer tissue and correlates with its more aggressive features. Polymorphisms of VEGFA alter the levels of expression and subsequently influence the susceptibility and aggressiveness of breast cancer. Assessment of VEGFA polymorphisms may be used for the identification of patients suitable for anti-VEGFA therapy.

Vascular endothelial growth factor (VEGF) gene polymorphisms and colorectal cancer: a meta-analysis of epidemiologic studies

BACKGROUND

Studies investigating the association between vascular endothelial growth factor (VEGF) polymorphisms and colorectal cancer (CRC) risk report conflicting results. To clarify the effect of four VEGF (-460T/C, -634G/C, +936C/T, and -2578C/A) gene polymorphisms on the risk of developing CRC, we carried out a meta-analysis using published data to obtain more precise estimates of risk.

METHODS

Electronic searches of PubMed and EMBASE were conducted to select studies for this meta-analysis. The principal outcome measure was the odds ratio (OR) with 95% confidence interval (CI) for the risk of CRC associated with four VEGF (-460T/C, -634G/C, +936C/T, and -2578C/A) gene polymorphisms.

RESULTS

We identified 12 epidemiologic studies, which included 2770 CRC cases and 2568 controls. The combined results based on all studies showed that CRC cases had a significantly higher frequency of VEGF -634GG (OR=1.24, 95% CI=1.06, 1.44) and -2578AA (OR=1.37, 95% CI=1.12, 1.66) genotype and a lower frequency of -634CG (OR=0.82, 95% CI=0.71, 0.95) than controls. When stratifying for race, we found that patients with CRC had a significantly higher frequency of -460TC (OR=1.54, 95% CI=1.22, 1.94), -460CC (OR=2.00, 95% CI=1.50, 2.67), and -2578AA (OR=1.38, 95% CI=1.12, 1.69) and a lower frequency of -2578AA (OR=0.78, 95% CI=0.65, 0.93) genotypes of VEGF than controls, among Caucasians. We also found that patients with CRC had a significantly higher frequency of -634GG (OR=1.61, 95% CI=1.20, 2.15) and a lower frequency of -634CG (OR=0.60, 95% CI=0.46, 0.79) genotypes of VEGF than controls, among Asians.

CONCLUSIONS

Our meta-analysis suggests that the VEGF -460T/C, -634G/C, and -2578C/A gene polymorphisms are associated with a risk of CRC.

Vascular endothelial growth factor -634G/C polymorphism associated with osteonecrosis of the femoral head in a Chinese population

An impeded blood flow through the femoral head is incriminated in the etiopathogenesis of osteonecrosis of the femoral head (ONFH). Vascular endothelial growth factor (VEGF) is a strong angiogenic protein and also plays a role in the formation of cartilage and bone. The aim of this study was to evaluate the association of VEGF -634G/C polymorphism with ONFH in a Chinese population. A total of 220 unrelated patients with nontraumatic ONFH and 220 unrelated control subjects were consecutively enrolled in a hospital-based case-control study. A polymerase chain reaction-restriction fragment length polymorphism analysis was used to detect the VEGF -634G/C genotype. Patients with ONFH had a significantly higher frequency of the CC genotype (odds ratio=1.64, 95% confidence interval=1.03, 2.60; p=0.04) than controls. There were no significant associations between any genotypes and the cause of ONFH. Our results support the hypothesis that the VEGF -634CC genotype is a risk factor of ONFH in the Chinese population. However, current results should be validated prospectively in larger cohorts.

Genetic variation in VEGF family genes and breast cancer risk: a report from the Shanghai Breast Cancer Genetics Study

BACKGROUND

In addition to mediating aspects of physiologic and pathologic angiogenesis, the VEGF family also contributes to carcinogenesis.

METHODS

We comprehensively characterized genetic variation across four VEGF family genes and evaluated associations with breast cancer risk with odds ratios (OR) and 95% CIs for participants of the two-stage case-control Shanghai Breast Cancer Genetics Study (SBCGS). Stage 1 evaluated 200 single nucleotide polymorphisms (SNP) across two VEGF ligands (VEGFA and VEGFC) and two VEGF receptors (FLT1/VEGFR1 and KDR/VEGFR2) among 2,079 cases and 2,148 controls. Five SNPs with promising associations were assessed in stage 2 among 4,419 cases and 1,851 controls.

RESULTS

Two SNPs were consistently associated with breast cancer risk across our two study stages and were significant in combined analyses. Compared with FLT1 rs9551471 major allele homozygotes (AA), reduced risks were associated with AG (OR = 0.92, 95% CI: 0.84-1.00) and GG (OR = 0.78, 95% CI: 0.64-0.95) genotypes (P(trend) = 0.005). Compared with VEGFA rs833070 major allele carriers (CC or CT), increased risk was associated with TT genotypes (OR = 1.26, 95% CI: 1.05-1.52, P = 0.016).

CONCLUSION

Results from our study indicate that common genetic variation in VEGFA and FLT1 (VEGFR1) may contribute to breast cancer susceptibility.

IMPACT

Our findings provide clues for future studies on VEGF family genes in relation to cancer susceptibility and survival.