Associations of single nucleotide polymorphisms in the vascular endothelial growth factor gene with the characteristics and prognosis of renal cell carcinomas

Two Single Nucleotide Polymorphisms in the Von Hippel-Lindau Tumor Suppressor Gene in Patients with Clear Cell Renal Cell Carcinoma

The most common subtype of renal cell carcinoma (RCC) is clear cell type (ccRCC), which accounts for approximately 75% of cases. von Hippel-Lindau (VHL) gene has been shown to be affected in more than half of ccRCC cases. Two single nucleotide polymorphisms (SNPs) located in VHL gene, rs779805 and rs1642742, are reported to be involved in the occurrence of ccRCC. The aim of this study was to assess their associations with clinicopathologic and immunohistochemical parameters, as well as risk and survival of ccRCC. The study population consisted of 129 patients. No significant differences in genotype or allele frequencies of VHL gene polymorphisms were observed between ccRCC cases and control population, and we have found that our results do not indicate a significant relationship of these SNPs with respect to ccRCC susceptibility. Additionally, we did not observe a significant association of these two SNPs with ccRCC survival. However, our results conclude that rs1642742 and rs779805 in the VHL gene are associated with increased tumor size, which is the most important prognostic indicator of renal cancer. Moreover, our analysis showed that patients with genotype AA of rs1642742 have a trend towards higher likelihood of developing ccRCC within their lifetime, while allele G of rs779805 can have a preventive effect against the development of renal cancer in stage 1. Therefore, these SNPs in VHL may be useful as genetic tumor markers for the molecular diagnostics for ccRCC patients.

Association of single nucleotide polymorphisms with renal cell carcinoma in Algerian population

Background

Renal cell carcinoma (RCC) is a common malignant tumor of the urinary system. The etiology of RCC is a complex interaction between environmental and multigenetic factors. Genome-wide association studies have identified new susceptibility risk loci for RCC. We examined associations of genetic variants of genes that are involved in metabolism, DNA repair and oncogenes with renal cancer risk. A total of 14 single nucleotide polymorphisms (SNPs) in 11 genes (VEGF, VHL, ATM, FAF1, LRRIQ4, RHOBTB2, OBFC1, DPF3, ALDH9A1 and EPAS1) were examined.

Methods

The current case–control study included 87 RCC patients and 114 controls matched for age, gender and ethnic origin. The 14 tag-SNPs were genotyped by Sequenom MassARRAY® iPLEX using blood genomic DNA.

Results

Genotype CG and allele G of ATM rs1800057 were significantly associated with RCC susceptibility (p = 0.043; OR = 8.47; CI = 1.00–71.76). Meanwhile, we found that genotype AA of rs67311347 polymorphism could increase the risk of RCC (p = 0.03; OR = 2.95; IC = 1.10–7.89). While, genotype TT and T allele of ALDH9A1 rs3845536 were observed to approach significance for a protective role against RCC (p = 0.007; OR = 0.26; CI = 0.09–0.70).

Conclusion

Our results indicate that ATM rs1800057 may have an effect on the risk of RCC, and suggest that ALDH9A1 was a protective factor against RCC in Algerian population.

Role of VEGFs/VEGFR-1 Signaling and its Inhibition in Modulating Tumor Invasion: Experimental Evidence in Different Metastatic Cancer Models

The vascular endothelial growth factor (VEGF) family members, VEGF-A, placenta growth factor (PlGF), and to a lesser extent VEGF-B, play an essential role in tumor-associated angiogenesis, tissue infiltration, and metastasis formation. Although VEGF-A can activate both VEGFR-1 and VEGFR-2 membrane receptors, PlGF and VEGF-B exclusively interact with VEGFR-1. Differently from VEGFR-2, which is involved both in physiological and pathological angiogenesis, in the adult VEGFR-1 is required only for pathological angiogenesis. Besides this role in tumor endothelium, ligand-mediated stimulation of VEGFR-1 expressed in tumor cells may directly induce cell chemotaxis and extracellular matrix invasion. Furthermore, VEGFR-1 activation in myeloid progenitors and tumor-associated macrophages favors cancer immune escape through the release of immunosuppressive cytokines. These properties have prompted a number of preclinical and clinical studies to analyze VEGFR-1 involvement in the metastatic process. The aim of the present review is to highlight the contribution of VEGFs/VEGFR-1 signaling in the progression of different tumor types and to provide an overview of the therapeutic approaches targeting VEGFR-1 currently under investigation.

Germline genetic variants in somatically significantly mutated genes in tumors are associated with renal cell carcinoma risk and outcome

Genome-wide association studies (GWAS) have identified 13 susceptibility loci for renal cell carcinoma (RCC). Additional genetic loci of risk remain to be explored. Moreover, the role of germline genetic variants in predicting RCC recurrence and overall survival (OS) is less understood. In this study, we focused on 127 significantly mutated genes from The Cancer Genome Atlas (TCGA) Pan-Cancer Analysis across 12 major cancer sites to identify potential genetic variants predictive of RCC risk and clinical outcomes. In a three-phase design with a total of 2657 RCC cases and 5315 healthy controls, two single nucleotide polymorphisms (SNPs) that map to PIK3CG (rs6466135:A, ORmeta = 0.85, 95% CI = 0.77-0.94, Pmeta = 1.4 × 10-3) and ATM (rs611646:T, ORmeta = 1.17, 95% CI = 1.05-1.31, Pmeta = 3.5 × 10-3) were significantly associated with RCC risk. With respect to RCC recurrence and OS, two separate datasets with a total of 661 stages I-III RCC patients (discovery: 367; validation: 294) were analyzed. The most significant association was observed for rs10932384:C (ERBB4) with both outcomes (recurrence: HRmeta = 0.52, 95% CI = 0.39-0.68, Pmeta = 3.81 × 10-6; OS: HRmeta = 0.50, 95% CI = 0.37-0.67, Pmeta = 6.00 × 10-6). In addition, six SNPs were significantly associated with either RCC recurrence or OS but not both (Pmeta < 0.01). Rs10932384:C was significantly correlated with mutation frequency of ERBB4 in clear cell RCC (ccRCC) patients (P = 0.003, Fisher's exact test). Cis-eQTL was observed for several SNPs in blood/transformed fibroblasts but not in RCC tumor tissues. In summary, we identified promising genetic predictors of recurrence and OS among RCC patients with localized disease.

Association between three VEGF polymorphisms and renal cell carcinoma susceptibility: a meta-analysis

Several studies have reported an association between vascular endothelial growth factor (VEGF) gene polymorphisms rs2010963, rs3025039 and rs699947 and renal cell carcinoma (RCC). However, the results remain inconclusive and controversial. We therefore conducted a meta-analysis to evaluate this association. Electronic databases were searched for relevant case-control studies up to November 2016. RevMan 5.2 software and STATA version 12.0 were used for statistical analysis in our meta-analysis. Heterogeneity was assessed using the I² value. Nine eligible studies were retrieved for detailed evaluation. The pooled estimates indicated that the GG genotype of VEGF rs2010963 polymorphism significantly decreased RCC risk [GG vs. GC+CC; GG vs. GC]. There was also a significant association between VEGF rs3025039 polymorphism and RCC susceptibility [CC+CT vs. TT; CC vs. TT]. Furthermore, a significant association between VEGF rs699947 polymorphism and RCC susceptibility was detected [A vs. C; AA+AC vs. CC; AA vs. AC+CC; AA vs. CC; AA vs. AC; AC vs. CC]. Subgroup analysis revealed that these associations held true especially for Asians. Our meta-analysis suggested that there may be a relationship between the VEGF rs2010963, rs3025039 and rs699947 polymorphisms and RCC susceptibility.

Association between vascular endothelial growth factor gene polymorphisms and the risk and prognosis of renal cell carcinoma: A systematic review and meta-analysis

The aim of the meta-analysis was to clarify the associations between vascular endothelial growth factor (VEGF) polymorphisms and the risk and prognosis of renal cell carcinoma (RCC). A meta-analysis was performed by searching the databases PubMed, EMBASE and Web of Science for the relevant available studies until August 1st, 2016, and fourteen studies met the inclusion criteria. The pooled odds ratios (ORs) with 95% confidence intervals (CIs) were calculated to evaluate the strength of such associations. Besides, the pooled hazard ratios (HRs) with 95% CIs were used to evaluate the overall survival (OS). Fixed- or random-effects models were conducted according to existence of heterogeneity. Publication bias was evaluated using Begg's funnel plots and Egger's regression test. Overall, this meta-analysis included a total of 8,275 patients, who had been accrued between November 2002 and September 2015. Meta-analysis indicated that -2578C/A, +936C/T and +405G/C polymorphisms in the VEGF gene correlated with elevated RCC risk, especially in Asian populations. Moreover, VEGF -1154G/A and -634C/G polymorphisms were found significantly associated with poor OS of RCC. Therefore, this meta-analysis revealed that VEGF -2578C/A, +936C/T, +405G/C polymorphisms were associated with an elevated susceptibility to RCC, indicating that these three polymorphisms might be risk factors for RCC, especially in Asian populations.

Vascular endothelial growth factor gene polymorphisms and the risk of renal cell carcinoma: Evidence from eight case-control studies

Background

Vascular endothelial growth factor (VEGF) protein plays important role in renal cell carcinoma (RCC) development and progression. VEGF gene polymorphisms can alter the protein concentrations and might be associated with renal cell carcinoma risk. However, the results of studies investigating the association between VEGF polymorphisms and renal cell carcinoma risk are inconsistent. Thus, a meta-analysis was performed.

Methods

We selected eligible studies via electronic searches. Only high-quality studies were included based on specific inclusion criteria and the Newcastle-Ottawa Scale (NOS).

Results

Eight studies primarily focusing on seven polymorphisms were included in our meta-analysis. Our results showed dramatically high risks for renal cell carcinoma were found regarding most genetic models and alleles of the +936C/T polymorphism (except CT vs. CC). In addition, significant increased renal cell carcinoma risks were found regarding all genetic models and alleles of the -2578C/A polymorphism. However, no significant associations were found between renal cell carcinoma risk and the +1612G/A, -460T/C, -634G/C, -405G/C or -1154G/A polymorphisms.

Conclusions

Our meta-analysis indicates that the +936C/T and -2578C/A polymorphisms of VEGF are associated with an increased risk for renal cell carcinoma. Additional rigorous analytical studies are needed to confirm our results.

Impact of vascular endothelial growth factor gene-gene and gene-smoking interaction and haplotype combination on bladder cancer risk in Chinese population

AIMS

To investigate the association of single nucleotide polymorphisms (SNPs) within vascular endothelial growth factor (VEGF) gene polymorphisms, additional gene- gene and gene- smoking interactions with bladder cancer risk.

RESULTS

Bladder cancer risk was significantly higher in carriers of the rs699947- A allele within VEGF gene than those with rs699947- CC genotype (CA+ AA versus CC), adjusted OR (95%CI) = 1.70 (1.16-2.31), and higher in carriers of the rs833052- A allele of within VEGF gene than those with rs833052- CC genotype (CA+ AA versus CC), adjusted OR (95%CI) = 1.65 (1.23-2.12). GMDR analysis indicated a potential interaction between rs2010963 and smoking on bladder cancer risk. Current smokers with rs2010963- GC+CC genotype within VEGF gene have the highest bladder cancer risk, compared to never smokers with rs2010963- GG genotype within VEGF gene, OR (95%CI) = 3.25 (1.71-4.83). Haplotype containing the rs2010963- C and rs833052- A alleles were associated with a statistically increased bladder cancer risk, OR (95%CI) = 2.21 (1.12-3.42).

MATERIALS AND METHODS

Generalized multifactor dimensionality reduction (GMDR) was used to screen the best interaction combination among SNPs and smoking. Logistic regression was performed to investigate association of 6 SNPs within VEGF gene, additional gene- gene and gene- smoking interaction with bladder cancer risk.

CONCLUSIONS

We found that the A allele of rs699947 and the A allele of rs833052 within VEGF gene, interaction between rs2010963 and smoking, haplotype containing the rs2010963- C and rs833052- A alleles were all associated with increased bladder cancer risk.

Genetic variation in IGF1 predicts renal cell carcinoma susceptibility and prognosis in Chinese population

Insulin-like growth factor 1 (IGF1) and IGF binding protein 3 (IGFBP3) play an important role in the development and progression of renal cell carcinoma (RCC). We evaluated the association of functional polymorphisms in IGF1 and IGFBP3 with susceptibility and prognosis of RCC. We genotyped nine potentially functional polymorphisms in IGF1 and IGFBP3 and assessed their association with risk of RCC in a two-stage case-control study compromising 1027 cases and 1094 controls, and with prognosis in a cohort of 311 patients. We found rs5742714 in the 3'-UTR of IGF1 was significantly associated with risk and prognosis of RCC. In the combined set, the rs5742714 GC/CC genotypes were significantly associated with decreased risk of RCC compared with the GG genotype (OR = 0.82; 95% CI = 0.68-0.98, P = 0.002). Furthermore, patients with the rs5742714 GC/CC genotypes showed improved survival than those with the GG genotype (Log-rank P = 0.025, HR = 0.36, 95% CI = 0.14-0.93). Besides, the rs5742714 GC/CC genotypes were associated with significantly decreased expression of IGF1 mRNA and lower IGF1 serum levels. Moreover, the luciferase reporter assays revealed the potential effect of rs5742714 genotype on the binding of microRNAs to IGF1. Our findings suggest that the IGF1 polymorphism rs5742714 may be a genetic predictor of susceptibility and prognosis of RCC.

Joint Effect of Urinary Total Arsenic Level and VEGF-A Genetic Polymorphisms on the Recurrence of Renal Cell Carcinoma

The results of our previous study suggested that high urinary total arsenic levels were associated with an increased risk of renal cell carcinoma (RCC). Germline genetic polymorphisms might also affect cancer risk and clinical outcomes. Vascular endothelial growth factor (VEGF) plays an important role in vasculogenesis and angiogenesis, but the combined effect of these factors on RCC remains unclear. In this study, we explored the association between the VEGF-A -2578C>A, -1498T>C, -1154G>A, -634G>C, and +936C>T gene polymorphisms and RCC. We also evaluated the combined effects of the VEGF-A haplotypes and urinary total arsenic levels on the prognosis of RCC. This case-control study was conducted with 191 RCC patients who were diagnosed with renal tumors on the basis of image-guided biopsy or surgical resections. An additional 376 age- and gender-matched controls were recruited. Concentrations of urinary arsenic species were determined by a high performance liquid chromatography-linked hydride generator and atomic absorption spectrometry. Genotyping was investigated using fluorescent-based TaqMan allelic discrimination. We observed no significant associations between VEGF-A haplotypes and RCC risk. However, the VEGF-A ACGG haplotype from VEGF-A -2578, -1498, -1154, and -634 was significantly associated with an increased recurrence of RCC (OR = 3.34, 95% CI = 1.03–10.91). Urinary total arsenic level was significantly associated with the risk of RCC in a dose-response manner, but it was not related to the recurrence of RCC. The combination of high urinary total arsenic level and VEGF-A risk haplotypes affected the OR of RCC recurrence in a dose-response manner. This is the first study to show that joint effect of high urinary total arsenic and VEGF-A risk haplotypes may influence the risk of RCC recurrence in humans who live in an area without obvious arsenic exposure.

Impact of VEGF gene polymorphisms in elderly cancer patients: clinical outcome and toxicity

Vascular endothelial growth factors (VEGFs) are the key regulators in angiogenesis and have been shown to play a significant role in the progression and prognosis of angiogenesis-related diseases, such as cancer. VEGF inhibitors are a current pharmacological tumoral strategy. However, despite the strong association between aging and cancer incidence and progression, recent findings suggest impaired angiogenesis accompanied by a reduced expression of VEGF in cells derived from aging subjects. Specific variations of VEGF genes have been demonstrated to be genetic determinants for susceptibility, outcome and therapy response, especially for the solid tumors. Considering the complications present in frail elderly patients, analysis of VEGF genetic polymorphisms in these subjects may further help in tailoring an angiogenic pharmacological strategy, and in improving our ability to better understand prognosis during therapy-related to cancer.

Predictive value of vascular endothelial growth factor polymorphisms on the clinical outcome of renal cell carcinoma patients

A cohort study was conducted to investigate the association between vascular endothelial growth factor (VEGF) polymorphisms −2578C/A, −1154G/A and −634C/G and the clinical outcome of renal cell carcinoma (RCC), as well as the interaction of VEGF polymorphisms with tumor stage, metastasis and size. A total of 310 RCC patients were recruited from the First Affiliated Hospital of Zhengzhou University (Zhengzhou, China) between January 2006 and December 2007, and were followed up until December 2012. The association between the three single nucleotide polymorphisms and the overall survival of RCC patients was estimated using Cox’s proportional hazard regression model. The median follow-up duration was 34.7 months and 74 of the RCC patients succumbed due to cancer during the follow-up period. The frequency of the VEGF −2578 AA genotype was significantly higher in patients classed as tumor stages III–IV (odds ratio [OR], 0.47; 95% confidence interval [CI], 0.24–0.95) and larger tumors (longest diameter, >4 cm; OR, 0.44; 95% CI, 0.22–0.89). Furthermore, the frequency of VEGF −634 GG was significantly higher in patients with larger tumors (longest diameter, >4 cm; OR, 0.68; 95% CI, 0.48–0.97). The VEGF −2578 AA genotype was correlated with a 2.96-fold increase in the risk of RCC-associated mortality and was associated with a five-year survival rate of ~25%. Therefore, the present study identified that the VEGF −2578C/A polymorphism may be associated with the prognosis of RCC patients, and may interact with the tumor stage and size.

Variants in angiogenesis-related genes and the risk of clear cell renal cell carcinoma

Angiogenesis is fundamentally important to the pathogenesis of clear cell renal cell carcinoma (ccRCC). We investigated the association between variations of genes related to angiogenesis and the risk of ccRCC. In a case-control study of 859 ccRCC patients and 1004 cancer-free subjects, we genotyped 24 potentially functional single nucleotide polymorphisms (SNPs) in seven angiogenesis-related genes (HIF1A, EPAS1, VEGFA, VEGFR1, VEGFR2, VEGFR3 and PDGFRB) using the TaqMan or Snapshot method. Unconditional logistic regression, adjusted for potential confounding factors, was used to assess the risk associations. The functionality of selected SNPs was assessed by real-time quantitative reverse transcription polymerase chain reaction (RT-PCR) and luciferase reporter gene assays. We found two SNPs (VEGFA rs2010963 and VEGFR3 rs448012) that were significantly associated with increased risk of ccRCC, after adjusting for multiple comparisons [rs2010963 CC/GC cf. GG: false discovery rate (FDR) = 0.048, odds ratio (OR) = 1.36, 95% confidence interval (95% CI) = 1.12-1.66; rs448012 CC/GC cf. GG: FDR = 0.048, OR = 1.38, 95% CI =1.13-1.69]. Real-time quantitative PCR revealed that the variant genotypes of rs2010963, but not rs448012, were associated with increased gene expression in normal tissues of ccRCC patients (CC/GC cf. GG: P = 0.036). The luciferase reporter assay showed that the rs2010963 C allele significantly increased luciferase activity over that of the rs2010963 G allele. Our results indicate that VEGFA rs2010963 and VEGFR3 rs448012 are associated with risk of ccRCC. Furthermore, rs2010963 is a functional SNP that may affect ccRCC susceptibility by modulating endogenous VEGFA expression.

Association of vascular endothelial growth factor polymorphisms with clinical outcome of renal cell carcinoma patients

We investigated the association of three single nucleotide polymorphisms (SNPs) in VEGF gene with the prognosis of renal cell carcinoma (RCC) and its association with clinical characteristics of RCC, such as tumor stages, metastasis, and tumor size. Polymerase chain reaction (PCR) restriction fragment length polymorphism analysis was used to genotype specimens for three polymorphisms (-2578C/A, -1154G/A, and -634G/C) in the VEGF gene. Hazard ratios (HRs) and their confidence intervals (CIs) were used to analyze the association of three SNPs in the VEGF gene with survival time using a multivariate Cox proportional hazards model. Frequencies of VEGF-2578AA genotype and A allele were significantly higher in patients with III-IV tumor stage or larger tumor size when compared with CC genotype. Moreover, frequencies of VEGF-634CC genotype and C allele were significantly higher in patients with tumor size >4 cm when compared with -634GG genotype. By Cox proportional hazards model, patients carrying VEGF-2578AA genotype and A allele significantly increased the risk of death from RCC, with the adjusted HRs (95 % CI) of 2.23 (1.15-4.36) and 1.55 (1.11-2.17), respectively. Our study suggests that VEGF-2578C/A and VEGF-634G/C polymorphisms may have effects on the prognosis of RCC. This finding might help in clarifying the mechanisms of RCC development and progression.

Association between vascular endothelial growth factor gene polymorphisms and bladder cancer risk

Vascular endothelial growth factor (VEGF) gene polymorphisms are associated with susceptibility to a number of cancers. The present case-controlled study aimed to investigate the correlation between VEGF gene polymorphisms and the risk of bladder cancer. The effects of VEGF polymorphisms were investigated in patients with bladder cancer and healthy controls in our hospital between May, 2008 and May, 2013. Peripheral blood samples were obtained from 480 patients with bladder cancer and 420 healthy controls. The polymerase chain reaction-restriction fragment length polymorphism technique was used to detect three VEGF gene polymorphisms (rs3025039 C/T, rs833052 C/A and rs1570360 G/A) in these subjects. The genotype and allele frequencies were also investigated in order to determine their association with stage, grade and histological type of bladder cancer, as well as smoking status. Our results suggested that the frequency of the rs833052 AA genotype was significantly higher in patients with bladder cancer [odds ratio (OR)=1.75; 95% confidence interval (CI): 1.05-2.92; P=0.03] compared to that in healthy controls. There was no significant correlation between the rs833052 AA genotype and bladder cancer stage, grade or histological type, whereas smoking was identified as a risk factor for bladder cancer in the included patients (OR=1.48; 95% CI: 1.13-1.93; P=0.004). The rs3025039 and rs1570360 gene polymorphisms were not found to be correlated with the risk of bladder cancer or its progression. In conclusion, our results suggested that the VEGF rs833052 C/A polymorphism may be associated with a modest increase in the risk of bladder cancer in Chinese individuals.

VEGF pathway polymorphisms as prognostic and pharmacogenetic factors in cancer: a 2013 update

With the recent advances in genomic medicine and the development of targeted antiangiogenic therapy for cancer patients, there has been an increased interest in the role of predictive and prognostic markers for antiangiogenic therapy. Here, we provide a summary of the angiogenesis pathway, the role of predictive and prognostic markers in cancer and a summary of the current literature and studies on predictive and prognostic markers for antiangiogenic therapy. Our aim is to summarize those studies that are currently in the literature with an emphasis on the future directions of the field from 2013 and beyond. We conclude by providing our perspective on the future directions of this growing field, as well as possible challenges and pitfalls along the way.

One-carbon metabolism pathway gene variants and risk of clear cell renal cell carcinoma in a Chinese population

Background

One-carbon metabolism is the basement of nucleotide synthesis and the methylation of DNA linked to cancer risk. Variations in one-carbon metabolism genes are reported to affect the risk of many cancers, including renal cancer, but little knowledge about this mechanism is known in Chinese population.

Methods

Each subject donated 5 mL venous blood after signing the agreement. The study was approved by the Institutional Review Board of the Nanjing Medical University, Nanjing, China. 18 SNPs in six one-carbon metabolism-related genes (CBS, MTHFR, MTR, MTRR, SHMT1, and TYMS) were genotyped in 859 clear cell renal cell carcinoma (ccRCC) patients and 1005 cancer-free controls by the Snapshot.

Results

Strong associations with ccRCC risk were observed for rs706209 (P = 0.006) in CBS and rs9332 (P = 0.027) in MTRR. Compared with those carrying none variant allele, individuals carrying one or more variant alleles in these two genes had a statistically significantly decreased risk of ccRCC [P = 0.001, adjusted odds ratio (OR) = 0.73, 95% confidence interval (CI) = 0.06–0.90]. In addition, patients carrying one or more variant alleles were more likely to develop localized stage disease (P = 0.002, adjusted OR = 1.37, 95%CI = 1.11–1.69) and well-differentiated ccRCC (P<0.001, adjusted OR = 1.42, 95%CI = 0.87–1.68). In the subgroup analysis, individuals carrying none variant allele in older group (P = 0.007, adjusted OR = 0.67, 95%CI = 0.49–0.91), male group (P = 0.007, adjusted OR = 0.71, 95%CI = 0.55–0.92), never smoking group (P = 0.002, adjusted OR = 0.68, 95%CI = 0.53–0.88) and never drinking group (P<0.001, adjusted OR = 0.68, 95%CI = 0.53–0.88) had an increased ccRCC risk.

Conclusions

Our results suggest that the polymorphisms of the one-carbon metabolism-related genes are associated with ccRCC risk in Chinese population. Future population-based prospective studies are required to confirm the results.

A functional insertion/deletion polymorphism (-94 ins/del ATTG) in the promoter region of the NFKB1 gene is related to the risk of renal cell carcinoma

OBJECTIVE

Activated nuclear factor-ĸB is associated with the pathogenesis of numerous malignancies, including renal cell carcinoma (RCC). This study aimed to clarify the influence of a common insertion/deletion polymorphism (-94 ins/del ATTG, rs28362491) in the NFKB1 promoter on RCC susceptibility.

METHODS

We genotyped the NFKB1 -94 ins/del ATTG promoter polymorphism by the TaqMan method and assessed the association with RCC risk, clinicopathological parameters in a case-control study of 1,027 cases and 1,094 controls.

RESULTS

The genotype frequencies were significantly different between RCC cases and controls (p = 0.046). Compared with individuals carrying the ins/del + del/del genotypes, those with the ins/ins genotype had an increased RCC risk [p = 0.036, adjusted odds ratio (OR) = 1.23, 95% confidence interval (CI) = 1.02-1.48], particularly in the subgroup of younger age (p = 0.005, adjusted OR = 1.42, 95% CI = 1.11-1.83) and never smokers (p = 0.013, adjusted OR = 1.34, 95% CI = 1.07-1.69). Furthermore, the polymorphism was significantly associated with the risk of developing localized stage RCC (p = 0.020, OR = 1.26, 95% CI = 1.04-1.53).

CONCLUSIONS

The functional NFKB1 promoter polymorphism is associated with an increased risk of RCC.

VEGF polymorphisms are not associated with an increased risk of developing renal cell carcinoma in Spanish population

PURPOSE

Vascular endothelial growth factor (VEGF) plays a central role in promoting angiogenesis and is over-expressed in renal cell cancer (RCC). Published data on the association between polymorphisms of vascular endothelial growth factor (e.g., -2578C/A [rs699947], -460T/C [rs833061], +405C/G [rs2010963], and +936C/T [rs3025039]) and the risk of renal cell carcinoma are ambiguous and controversial. The aim of this investigation was to investigate this relationship in a series of Caucasian Spanish patients.

MATERIALS AND METHODS

A case-control study was performed with 216 cases and 280 controls, genotyping subjects for VEGF polymorphisms using the predesigned TaqMan single nucleotide polymorphism (SNP) genotyping assay (Applied Biosystems, Foster City, CA, USA). The combined effect of the four gene polymorphisms on overall survival was studied by haplotype analysis.

RESULTS

The overall results suggest that polymorphisms or haplotypes in the VEGF gene do not modify the risk of RCC. We were unable to replicate the association of the -460T/C (rs833061) polymorphism with renal cancer risk. Data were also gathered on clinical-pathological results, tumor size, clinical stage, histological grade, and survival.

CONCLUSIONS

According to our analysis of their contribution to prognostic factors, VEGF polymorphisms do not appear to exert a significant influence on RCC progression or prognosis. This finding might be explained by the tumor biology and pathogenesis of clear cell RCC. Additional studies with larger sample sizes are needed in different ethnic groups to further assess this association.

Biomarkers: the next therapeutic hurdle in metastatic renal cell carcinoma

Despite recent advances, metastatic renal cell carcinoma remains largely an incurable disease. Vascular endothelial growth factor and mammalian target of rapamycin inhibitors have provided improvements in clinical outcomes. High-dose interleukin 2 remains an option for highly selected patients and is associated with durable remissions in a small minority of patients. The toxicity profiles of specific agents and patient characteristics and comorbidities and costs have an important role in the current choice of therapy. Major challenges encountered in developing molecular biomarkers to guide therapy are tumour heterogeneity and standardisation of tissue collection and analysis. Although biomarkers are in their infancy of development, they should be a priority in early preclinical and clinical development in order to guide rational tailored development of emerging agents.

Vascular endothelial growth factor pathway polymorphisms as prognostic and pharmacogenetic factors in cancer: a systematic review and meta-analysis

Angiogenesis is an important host process that interacts with cancer cells to promote growth, invasion, and metastasis. Numerous therapeutic agents targeting the VEGF pathway have been developed. Host variability in VEGF pathway can influence angiogenesis-dependent signaling, altering sensitivity to antiangiogenic drugs and prognosis. A systematic review and meta-analysis was conducted (May 1990-July 2011). Eligible studies involved cancer patients and compared polymorphisms in the VEGF pathway [VEGF and molecules directly interacting with VEGF: KDR, FLT1, FGF, FGF2, FGFR, NRP1, endostatin (encoded by COL18A1)], and reported one of the following outcomes: overall survival, progression-free survival, time to recurrence, disease-free survival, response rate, or drug toxicity. We identified 48 cancer studies assessing prognosis and 12 cancer studies exploring pharmacogenetics of anti-VEGF therapy across various VEGF pathway polymorphisms. There was marked inter- and intradisease site heterogeneity in the effect of polymorphisms on both outcome and response to therapy. Meta-analyses of 5 VEGF polymorphisms (+936C>T, -460T>C, +405G>C, -1154G>A, and -2578C>A) identified a significant prognostic relationship: VEGF +405G>C variants showed a highly statistically significant improvement in overall survival [HR, 0.74; 95% confidence interval, 0.60-0.91; P = 0.004]. Variants (heterozygotes and/or homozygotes) of VEGF +405G>C were significantly associated with improved survival in a meta-analysis of multiple cancer sites.

Vascular endothelial growth factor polymorphisms in patients with steroid-induced femoral head osteonecrosis

To investigate an association between steroid-induced femoral head osteonecrosis (FHON) and functional vascular endothelial growth factor (VEGF) gene (-2578A/C, -1154A/G, -634C/G, and +405C/G) polymorphisms polymerase chain reaction-restriction fragment length polymorphism genotyping was performed in 160 patients (86 idiopathic FHON and 74 steroid-induced FHON) and 160 gender- and age-matched controls. The steroid-induced subgroup had a significantly lower prevalence of -1154A allele (7.4% vs. 18.1%, odds ratio (OR) = 0.363) and genotype carrying -1154A (14.9% vs. 32.5%, OR = 0.333 in a recessive model) than controls. In a dominant model, the frequency of genotype carrying +405G (74.3% vs. 84.4%, OR = 0.492) was significantly lower in steroid-induced FHON than in controls. The distribution of haplotypes was significantly different between controls and FHON patients (p = 0.00011). Especially, when haplotypes were classified into high (CGCG and AAGG) or low (CGGC and AGGC) VEGF inducing haplotypes, patients with steroid-induced FHON had a significantly lower prevalence of high inducing haplotypes (7.4% vs. 15.9%, OR = 0.424) and a significantly higher prevalence of low inducing haplotypes (4.7% vs. 0.6%, OR = 7.894) than controls. Low inducing VEGF haplotypes may confer an increased risk and high inducing haplotypes have a protective effect for the development of steroid-induced FHON in Korea.

Delivering preventive, predictive and personalised cancer medicine for renal cell carcinoma: the challenge of tumour heterogeneity

Recent years have seen major advances in the management of metastatic renal cell carcinoma (mRCC). The tyrosine kinase and mammalian target of rapamycin inhibitors have resulted in disease control and improved survival for many patients with mRCC, but they have not led to preventive, predictive or personalised medicine (PPPM). Failure to achieve this rests ultimately with inadequate knowledge of tissue and molecular heterogeneity; discovery of these drugs was based upon identification of pathogenic molecular pathways in RCC, but research into molecular factors which underpin drug response, resistance and selection of therapy for individual patients has lagged well behind clinical trials of drug development. This review will provide an overview of the development of targeted drug therapies for mRCC, will discuss the challenges which currently impede the delivery of PPPM, including identification of biomarkers, drug resistance and molecular heterogeneity, and will propose research methodologies and technologies required to overcome these obstacles.

Association of VEGF and VEGFR2 single nucleotide polymorphisms with hypertension and clinical outcome in metastatic clear cell renal cell carcinoma patients treated with sunitinib

PURPOSE

Biomarkers that predict response or toxicity to antiangiogenic therapy are sought to favorably inform the risk/benefit ratio. This study evaluated the association of vascular endothelial growth factor (VEGF) and VEGF receptor 2 (VEGFR2) genetic polymorphisms with the development of hypertension (HTN) and clinical outcome in metastatic clear cell renal cell carcinoma (MCCRCC) patients treated with sunitinib.

PATIENT AND METHODS

Sixty-three MCCRCC patients receiving sunitinib (50 mg 4/2) with available blood pressure (BP) data and germline DNA were retrospectively identified. A panel of candidate VEGF and VEGFR2 single nucleotide polymorphisms (SNPs) were evaluated for associations with the development of hypertension and clinical outcome.

RESULTS

VEGF SNP -634 genotype was associated with the prevalence and duration of sunitinib-induced hypertension (as defined by systolic pressure ≥150 mmHg and/or diastolic pressure ≥90 mmHg) in both univariable analysis (P = .03 and .01, respectively) and multivariable analysis, which adjusted for baseline BP and use of antihypertension medication (P = .05 and .02, respectively). Patients with the GG genotype were estimated to have a greater likelihood of being hypertensive during treatment compared with patients with the CC genotype (odds ratio of 13.62, 95% confidence interval [CI] 3.71-50.04). No single VEGF or VEGFR SNPs were found to correlate with clinical outcome. However, the combination of VEGF SNP 936 and VEGFR2 SNP 889 were associated with overall survival after adjustment for prognostic risk group (P = .03).

CONCLUSIONS

In MCCRCC patients treated with sunitinib, VEGF SNP -634 is associated with hypertension and a combination of VEGF SNP 936 and VEGFR2 SNP 889 genotypes is associated with overall survival.

The polymorphisms in the VHL and HIF1A genes are associated with the prognosis but not the development of renal cell carcinoma

BACKGROUND

The von Hippel-Lindau (VHL) tumor suppressor gene and hypoxia-inducible factor-1α (HIF1A) play a pivotal role in renal carcinogenesis. This study was aimed to clarify the influence of VHL and HIF1A polymorphisms on renal cell cancer (RCC) susceptibility and survival.

SUBJECTS AND METHODS

We genotyped four potentially functional single-nucleotide polymorphisms (rs779805 in VHL and rs11549465, rs11549467, and rs2057482 in HIF1A) and assessed their associations with RCC risk, clinicopathologic parameters in a case-control study of 620 patients and 623 controls, and the prognosis of RCC in a cohort of 311 patients.

RESULTS

No significant differences in VHL or HIF1A genotypes were observed between RCC cases and controls. However, individuals with ≥2 variant alleles of the four polymorphisms were associated with less frequent lymph node metastasis and lower clinical stage (P = 0.032 and P = 0.041, respectively). And the number of variant alleles was associated with improved survival in a dose-response manner (P(trend) = 0.013). Furthermore, multivariate Cox regression analysis showed that the number of variant alleles (≥1 versus 0) was an independent prognostic factor for RCC survival (P = 0.036) together with clinical stage and tumor grade.

CONCLUSION

The VHL and HIF1A polymorphisms may not influence RCC susceptibility but may jointly influence RCC progression and survival.

Association of common variants of vascular endothelial growth factor and interleukin-18 genes with allograft survival in renal transplant recipients of North India

Increased vascular endothelial growth factor (VEGF) production promotes enhanced endothelial permeability, enhanced leukocyte migration into the allograft, thereby leading to a clinically recognized rejection episode. Interleukin-18 (IL-18), a potent proinflammatory cytokine, may also be involved in mechanisms of kidney allograft rejection. The present study was, therefore, undertaken to investigate the association of functional polymorphisms in VEGF (2578C>A, 1154A>G) and IL-18 (607C>A, 137G>C) genes with risk of allograft rejection in renal transplant recipients of North India. Two hundred renal transplant recipients, 150 matched recipients-donors, and 200 unrelated healthy individuals were genotyped by amplification refractory mutation specific polymerase chain reaction and by polymerase chain reaction-restriction fragment length polymorphism. Variant allele VEGF 1154A>G (p = 0.56; odds ratio [OR] = 1.32) and variant allele (p = 0.004, OR = 1.54) and variant genotype (p = 0.007, OR = 3.26) of IL-18 607C>A, GC of IL-18 137G>C (p = 0.043, OR = 0.63) were significantly different in healthy individuals as compared with the patients with renal transplant. When 114 nonrejectors were compared with 36 rejectors (150 recipients) for association with allograft rejection, significant association was observed in heterozygous genotype of VEGF 2578C>A (p = 0.033), VEGF 1154A>G (p = 0.024). In IL-18 137G>C, CC genotype, C allele showed protective association with allograft rejection. Kaplan-Meier analysis indicated a higher mean time for first rejection episode in CA genotype carriers (31 months) as compared with AA (29 months) for VEGF 2578C>A (log p = 0.035). In VEGF, the haplotypes A-A and A-G (2578-1154) were associated with reduced risk and in IL-18 607A-137G, they were associated with high risk for allograft rejection. This observation suggests these polymorphisms are an ideal marker for prediction of pretransplant allograft outcome.

Association of vascular endothelial growth factor gene polymorphisms with susceptibility to epithelial ovarian cancer

BACKGROUND

Vascular endothelial growth factor (VEGF) is a major angiogenic factor involved in a number of pathological processes, including neovascularization, a crucial step in the development of solid malignancies. The aim of this study was to investigate the association of polymorphisms in the VEGF gene with susceptibility to epithelial ovarian cancer (EOC).

METHODS

This case-control study included 303 EOC patients and 303 healthy controls. Genotyping of the VEGF gene polymorphisms at j460C/T, j1154G/A, j2578C/A, and +936C/T were performed by polymerase chain reaction and restriction fragment length polymorphism analysis.

RESULTS

No significant difference was found in allele and genotype distributions of the -460C/T, +936C/T, and -2578C/A polymorphisms between patients and controls. However, the frequencies of -1154G/A genotype and allele were significantly different between the two groups (P = 0.037, P = 0.013). Compared with the G/A + A/A genotype, the G/G genotype could significantly increase the risk of developing EOC (odds ratio, 1.64; 95% confidence interval, 1.12Y2.39). The haplotype analysis suggested that the -460T/ -1154A/ -2578C haplotype exhibited a decrease in the risk of developing EOC compared with the -460T/ -1154G/ -2578C haplotype (odds ratio, 0.644; 95% confidence interval, 0.415-0.999).

CONCLUSIONS

The study suggested a possible association between the VEGF -1154G/A polymorphism with susceptibility to EOC, but there is no support for an association of the VEGF -460C/T, +936C/T, and -2578C/A polymorphisms with the risk for EOC.

VEGF polymorphisms are associated with an increasing risk of developing renal cell carcinoma

PURPOSE

Vascular endothelial cell growth factor is studied in different malignant tumors as a key endothelial cell mitogen. Many single nucleotide polymorphisms in the VEGF gene have been described. We compared VEGF gene polymorphisms between a control group and a renal cancer group.

MATERIALS AND METHODS

This study was performed in 202 control, white, healthy blood donors (control group) and in 51 consecutive patients with renal cell carcinoma. We studied VEGF genotype polymorphisms at positions -2549, -460, -1154, +405 and +936 using polymerase chain restriction fragment length polymorphism, and looked for correlations with clinical data.

RESULTS

No association was found between VEGF gene polymorphism and renal cell carcinoma prognostic parameters. However, in contrast as observed for controls and other polymorphisms the patient group displayed a heterozygote excess (p = 0.0179, 35.9% more than that expected) at the -460 polymorphism. Comparing the control group and the renal cell carcinoma group we detected a significantly increased risk of renal cell carcinoma in subjects with the C-460T polymorphism. T carrier genotypes and the T allele increased the risk of renal cell carcinoma with an OR of 14.15 (95% CI 1.900-105.41, p = 0.0017) and 2.14 (95% CI 1.34-3.419, p = 0.0018), respectively. The genotype at the -2549 polymorphism exhibited a nonsignificant trend for increased risk but the D allele was significantly associated with increased risk (p = 0.0305).

CONCLUSIONS

Our results suggest that the -460 polymorphism is a risk factor for renal cancer. An individual screening test could be proposed for high risk populations.

Genotypes and haplotypes of the VEGF gene and survival in locally advanced non-small cell lung cancer patients treated with chemoradiotherapy

BACKGROUND

Vascular endothelial growth factor (VEGF) is a major mediator of angiogenesis involving in carcinogenesis, including lung cancer. We hypothesized that VEGF polymorphisms may affect survival outcomes among locally advanced non-small cell lung cancer (LA-NSCLC) patients.

METHODS

We genotyped three potentially functional VEGF variants [-460 T > C (rs833061), -634 G > C (rs2010963), and +936 C > T (rs3025039)] and estimated haplotypes in 124 Caucasian patients with LA-NSCLC treated with definitive radiotherapy. We used Kaplan-Meier log-rank tests, and Cox proportional hazard models to evaluate the association between VEGF variants and overall survival (OS).

RESULTS

Gender, Karnofsky's performance scores (KPS) and clinical stage seemed to influence the OS. The variant C genotypes were independently associated with significantly improved OS (CT+CC vs. TT: adjusted hazard ratio [HR] = 0.58; 95% confidence interval [CI] = 0.37-0.92, P = 0.022), compared with the VEGF -460 TT genotype.

CONCLUSIONS

Our study suggests that VEGF -460 C genotypes may be associated with a better survival of LA-NSCLC patients after chemoradiotherapy. Large studies are needed to confirm our findings.

Vascular endothelial growth factor polymorphisms: role in response and toxicity of tyrosine kinase inhibitors

Angiogenesis is central to the growth of normal tissues and tumors. Inhibiting this pathway has been a strategy for drug development for tumors not responsive to most agents used in chemotherapy. Notably, signaling mediated by vascular endothelial growth factor (VEGF) is a key target because aberrant signaling via this pathway is frequently associated with neoangiogenesis in tumors. The drug-discovery effort to blunt VEGF signaling has led to the approval of bevacizumab and several receptor tyrosine kinase inhibitors (TKIs) that have shown efficacy in the clinical management of breast, colorectal, lung, and kidney cancer. Understanding the genetic variability in VEGF and VEGF receptor has led to identifying genotypic variations (single nucleotide polymorphisms [SNPs]) associated with treatment outcome and toxicity. Notably, identification of SNPs in VEGF associated with angiogenesis inhibitor treatment-induced hypertension and outcome provides exciting opportunities for personalized medicine to improve outcome and reduced toxicity with these novel TKIs.

The prognostic value of haplotypes in the vascular endothelial growth factor a gene in colorectal cancer

New prognostic markers in patients with colorectal cancer (CRC) are a prerequisite for individualized treatment. Prognostic importance of single nucleotide polymorphisms (SNPs) in the vascular endothelial growth factor A (VEGF-A) gene has been proposed. The objective of the present study was to investigate the prognostic importance of haplotypes in the VEGF-A gene in patients with CRC. The study included 486 patients surgically resected for stage II and III CRC, divided into two independent cohorts. Three SNPs in the VEGF-A gene were analyzed by polymerase chain reaction. Haplotypes were estimated using the PHASE program. The prognostic influence was evaluated using Kaplan-Meir plots and log rank tests. Cox regression method was used to analyze the independent prognostic importance of different markers. All three SNPs were significantly related to survival. A haplotype combination, responsible for this effect, was present in approximately 30% of the patients and demonstrated a significant relationship with poor survival, and it remained an independent prognostic marker after multivariate analysis, hazard ratio 2.46 (95% confidence interval 1.49–4.06), p < 0.001. Validation was provided by consistent findings in a second and independent cohort. Haplotype combinations call for further investigation.

Vascular endothelial growth factor (VEGF) and endothelial nitric oxide synthase (NOS3) polymorphisms are associated with high relapse risk in childhood acute lymphoblastic leukemia (ALL)

BACKGROUND

Angiogenesis has been shown as an important process in hematological malignancies. It consists in endothelial proliferation, migration, and tube formation following pro-angiogenic factors releasing, specially the vascular endothelial growth factor (VEGF), which angiogenic effect seems to be dependent on nitric oxide (NO). We examined the association among functional polymorphisms in these two angiogenesis related genes: VEGF (-2578C>A, -1154G>A, and -634G>C) and NOS3 (-786T>C, intron 4 b>a, and Glu298Asp) with prognosis of childhood acute lymphoblastic leukemia (ALL).

METHODS

The genotypes were determined and haplotypes estimated in 105 ALL patients that were divided in 2 groups: high risk (HR) and low risk of relapse (LR) patients. In addition, event-free survival curves according to genotypes were assessed.

RESULTS

The group HR compared to the LR showed a higher frequency of the alleles -2578C and -634C and the haplotype CGC for VEGF (0.72 vs. 0.51, p<0.008; 0.47 vs. 0.26, p<0.008; and 42.1 vs. 14.5, p<0.006; respectively) and a lower frequency of the haplotype CbGlu (0.4 vs. 8.8,p<0.006), for NOS3.

CONCLUSION

Polymorphisms of VEGF and NOS3 genes are associated with high risk of relapse, therefore may have a prognostic impact in childhood ALL.

Gender-specific association of methylenetetrahydrofolate reductase genotype and haplotype with the aggressiveness and prognosis of clear cell renal cell carcinoma in Japanese patients

OBJECTIVE

To determine if the two common polymorphisms in the methylenetetrahydrofolate reductase (MTHFR) gene, C677T and A1298C, affect tumour aggressiveness or prognosis of clear cell renal cell carcinoma (CCRCC) in Japanese patients.

PATIENTS AND METHODS

MTHFR C677T and A1298C polymorphisms have been reported to cause decreased enzyme activity, which reduces the quantity of methyl groups available for DNA methylation and leads to mis-incorporation of uracil into DNA, resulting in single-strand DNA breaks. These effects might induce the accumulation of several genetic changes, leading to the development and progression of CCRCC. Therefore, we investigated the associations between MTHFR genotypes and haplotypes and the clinicopathological characteristics and survival rates in 240 Japanese patients with histopathologically confirmed CCRCC. MTHFR C677T and A1298C were genotyped and haplotypes were analysed using appropriate software.

RESULTS

The variant genotypes of MTHFR A1298C were significantly associated with some advanced characteristics of CCRCC in all patients, and these associations were stronger among men. However, among women, the variant genotypes of MTHFR C677T were associated with some advanced characteristics of CCRCC and the C677T variant genotypes or the 677T-1298A haplotype was significantly associated with decreased overall survival (P = 0.007 and P = 0.009, respectively).

CONCLUSION

To our knowledge, this is the first report on the association between MTHFR polymorphisms and CCRCC aggressiveness or prognosis. These results suggest that the MTHFR genotypes and haplotype might be useful, in a gender-specific manner, as predictive factors for the clinical course of CCRCC. Furthermore, these findings will contribute to the understanding of the mechanisms underlying CCRCC progression.

Association of VEGF genetic polymorphisms with the clinical characteristics of non-Hodgkin's lymphoma

PURPOSE

Vascular endothelial growth factor (VEGF) plays an important role in tumor angiogenesis and cancer progression. The VEGF genetic polymorphisms were shown to be independently associated with an adverse outcome in various malignancies. We investigated the possible associations of two polymorphisms (-2578C/A and +936C/T) in the VEGF gene with the clinicopathologic parameters for patients with non-Hodgkin's lymphoma (NHL).

METHODS

We studied the genotype and allele frequencies of the -2578C/A and +936C/T polymorphism in DNA samples of 431 patients with NHL using restriction fragment length polymorphism typing analysis.

RESULTS

The -2578A allele was significantly associated with less frequent clinical staging III, IV and bone marrow involvement (The odds ratio (OR) 0.59; 95% confidence interval (CI) 0.43-0.82; and OR 0.66; 95% CI 0.48-0.91, respectively). The CA and CA + AA genotype of the -2578C/A were significantly associated with less frequent bone marrow involvement than CC genotypes (OR 0.57; 95% CI 0.38-0.86; and OR 0.57; 95% CI 0.39-0.85, respectively). The TT genotype of the +936C/T polymorphism was significantly associated with less frequent T cell histological type, clinical staging III, IV and bone marrow involvement (OR 0.25; 95% CI 0.07-0.89; OR 0.37; 95% CI 0.15-0.89; and OR 0.31; 95% CI 0.10-0.96, respectively). The +936 T allele was marginally associated with less frequent bone marrow involvement and with Clinical staging III, IV (OR 0.71; 95% CI 0.49-1.01; and OR 0.70; 95% CI 0.49-1.00, respectively). None of the evaluated genotypes of -2578C/A was significantly associated with the gender, age, tumor size, B symptoms and immunohistological subtype. No significant associations between the genotype of +936C/T and the clinicopathologic variables, gender, age, tumor size and B symptoms were ascertained. Both of the -2578C/A and +936C/T polymorphisms were not related to the patients' overall survival.

CONCLUSION

We present the first data on VEGF gene polymorphisms in NHL. Our findings support the hypothesis that the -2578 CA and CA + AA and +936 TT VEGF genotypes and -2578A and +936T alleles are associated with decreased risk for invasion. But the investigated VEGF gene polymorphisms were not associated with prognosis in patients with NHL.

Common polymorphisms in the vascular endothelial growth factor gene and colorectal cancer development, prognosis, and survival

Angiogenesis plays an important role in growth, progression, and metastasis of tumors. The most important regulator of angiogenesis is vascular endothelial growth factor (VEGF). VEGF expression has been associated with advance stage and poor survival of several cancers. In the present study we evaluated the association of functional polymorphisms in the VEGF gene with colorectal cancer development, prognosis, and survival. Three hundred twelve consecutive patients with surgically treated colorectal adenocarcinoma were enrolled in the present study. The genomic DNA was extracted from paraffin-embedded tissue and five VEGF (-2578C>A, -1154G>A, -634G>C, -460T>C, and +936C>T) gene polymorphisms were determined using a polymerase chain reaction-restriction fragment length polymorphism assay. VEGF -2578C>A, -1154G>A, -634G>C, -460T>C, and +936C>T genotype and allele frequencies were similar among patients and controls. There was a trend showing carriers of the -2578A and +936T alleles more frequent among patients with CRC, but these differences did not reach statistical significance. Furthermore, no correlation was found between all these variants and tumor characteristics like size, histological grading, positive regional lymph node metastases or tumor stage. However, the -2578AA, -634CC, and +936TT genotypes found to be related with a significantly lower overall survival in our study. In conclusion, VEGF gene polymorphisms were found to be an independent prognostic marker for Greek CRC patients.

Vascular endothelial growth factor gene polymorphisms are associated with the risk of developing adenomyosis

Vascular endothelial growth factor (VEGF), a major mediator of angiogenesis and vascular permeability, may play a key role in the development of adenomyosis. The aim of this study was to investigate whether these four VEGF polymorphisms (-2578C/A, -1154G/A, -460C/T, and +936C/T) were associated with the risk of adenomyosis development. Genotypes were determined by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) assay in 174 adenomyosis patients and 199 frequency-matched control women. There were significant differences between patients and control group in allele frequencies and genotype distributions of the -2578C/A polymorphisms (P = 0.010 and 0.044, respectively). Compared with the C/C genotype, the A/A + C/A genotype could significantly modify the risk of developing adenomyosis [odds ratio (OR) = 0.64, 95% confidence interval (CI) = 0.42-0.97]. For the -1154G/A polymorphism, the allele frequencies and genotype distributions in patient group were significant different from those of the controls (P = 0.001 and 0.007, respectively). Compared with the G/G genotype, the A/A + G/A genotype could significantly decrease the risk of developing adenomyosis (OR = 0.51, 95% CI = 0.33-0.80). However, the genotype distributions and allele frequencies of the -460C/T and +936C/T polymorphisms did not significantly differ between controls and patients (all P value > 0.05). The haplotype analysis suggested that the TGA (VEGF -460/-1154/-2578) and CGA haplotypes exhibited a significant decrease in the risk of developing adenomyosis compared with the haplotype of TGC (OR = 0.64, 95% CI = 0.41-1.00; OR = 0.44, 95% CI = 0.21-0.93, respectively). The study indicated that the -2578A or -1154A allele of VEGF gene could significantly decrease the risk of adenomyosis and might be potentially protective factors for adenomyosis development.

Polymorphism of VEGF-2578C/A associated with the risk and aggressiveness of nasopharyngeal carcinoma in a Chinese population

Polymorphism of vascular endothelial growth factor (VEGF) influences the VEGF responsiveness and is implicated in various types of diseases with a putative angiogenic basis, but its role in nasopharyngeal carcinoma (NPC) is not fully understood. In this report, we sought to investigate whether the VEGF-2578C/A polymorphism was associated with NPC in a Chinese population. We carried out polymerase chain reaction-restriction fragment length polymorphism in blood genomic DNA of 156 NPC patients and 161 control subjects. The VEGF-2578A allele carriers were significantly associated with an increased risk of NPC (odds ratio: 1.648; 95% confidence interval: 1.053-2.580; P = 0.029). In contrast, NPC patients with the -2578CC genotype were shown higher tumor aggressiveness of large tumor size, poor differentiation and advanced stage as compared to the -2578A allele carriers. No correlation was observed between the genotype or allele distribution and lymph node metastasis or family history of cancer. The VEGF-2578C/A polymorphism was shown to be inconsistent with the onset and aggressiveness of NPC. The precise mechanisms of the polymorphism on the differing status in NPC should be elucidated in further studies.

Pharmacogenetics in chemotherapy of colorectal cancer

Although in recent years, chemotherapeutic options for colorectal carcinoma have expanded, overall response rates are still too low, with high rates of toxicity. Pharmacogenetics aim at predicting both treatment response and adverse effects in individual patients. This review describes the current knowledge of pharmacogenetic markers in the systemic treatment of colorectal cancer. UGT1A1*28 leads to reduced conjugation of SN-38, the active metabolite of irinotecan, resulting in an increased rate of adverse effects, especially neutropenia. To a lesser extent, increased 5-FU toxicity is predicted by DPYD*2A. A variable number of tandem repeats polymorphism in the thymidylate synthase enhancer region, in combination with a single nucleotide polymorphism C>G, may predict poorer response to 5-FU. Efficacy of oxaliplatin is influenced by polymorphisms in components of DNA repair systems, such as ERCC1 and XRCC1. Polymorphic changes in the endothelial growth factor receptor probably predict cetuximab efficacy. Furthermore, the antibody-depended cell-mediated cytotoxic effect of cetuximab may be reduced by polymorphisms in the immunoglobin G fragment C receptors. Bevacizumab efficacy is suspected to be influenced by polymorphisms in the VEGF gene and the hypoxia inducible factor 1alpha gene. Although the interpretation of pharmacogenetic studies is complicated, results imply a promising way of pretreatment prediction of chemotherapy efficacy and toxicity.

Genetics, epigenetics and pharmaco-(epi)genomics in angiogenesis

Angiogenesis is controlled by a balance between pro- and anti-angiogenic factors. Studies in mice and human beings have shown that this balance, as well as the general sensitivity of the endothelium to these factors, is genetically pre-determined. In an effort to dissect this genetic basis, different types of genetic variability have emerged: mutations and translocations in angiogenic factors have been linked to several vascular malformations and haemangiomas, whereas SNPs have been associated with complex genetic disorders, such as cancer, neurodegeneration and diabetes. In addition, copy number alterations of angiogenic factors have been reported in several tumours. More recently, epigenetic changes caused by aberrant DNA methylation or histone acetylation of anti-angiogenic molecules have been shown to determine angiogenesis as well. Initial studies also revealed a crucial role for microRNAs in stimulating or reducing angiogenesis. So far, most of these genetic studies have focused on tumour angiogenesis, but future research is expected to improve our understanding of how genetic variants determine angiogenesis in other diseases. Importantly, these genetic insights might also be of important clinical relevance for the use of anti-angiogenic strategies in cancer or macular degeneration.

An analysis of growth, differentiation and apoptosis genes with risk of renal cancer

We conducted a case-control study of renal cancer (987 cases and 1298 controls) in Central and Eastern Europe and analyzed genomic DNA for 319 tagging single-nucleotide polymorphisms (SNPs) in 21 genes involved in cellular growth, differentiation and apoptosis using an Illumina Oligo Pool All (OPA). A haplotype-based method (sliding window analysis of consecutive SNPs) was used to identify chromosome regions of interest that remained significant at a false discovery rate of 10%. Subsequently, risk estimates were generated for regions with a high level of signal and individual SNPs by unconditional logistic regression adjusting for age, gender and study center. Three regions containing genes associated with renal cancer were identified: caspase 1/5/4/12(CASP 1/5/4/12), epidermal growth factor receptor (EGFR), and insulin-like growth factor binding protein-3 (IGFBP3). We observed that individuals with CASP1/5/4/12 haplotype (spanning area upstream of CASP1 through exon 2 of CASP5) GGGCTCAGT were at higher risk of renal cancer compared to individuals with the most common haplotype (OR:1.40, 95% CI:1.10–1.78, p-value = 0.007). Analysis of EGFR revealed three strong signals within intron 1, particularly a region centered around rs759158 with a global p = 0.006 (GGG: OR:1.26, 95% CI:1.04–1.53 and ATG: OR:1.55, 95% CI:1.14–2.11). A region in IGFBP3 was also associated with increased risk (global p = 0.04). In addition, the number of statistically significant (p-value<0.05) SNP associations observed within these three genes was higher than would be expected by chance on a gene level. To our knowledge, this is the first study to evaluate these genes in relation to renal cancer and there is need to replicate and extend our findings. The specific regions associated with risk may have particular relevance for gene function and/or carcinogenesis. In conclusion, our evaluation has identified common genetic variants in CASP1, CASP5, EGFR, and IGFBP3 that could be associated with renal cancer risk.