Impact of Vascular Endothelial Growth Factor Gene Polymorphisms and Their Interactions with Environmental Factors on Susceptibility to Renal Cell Carcinoma.

AIMS

This study aimed to investigate the association of single nucleotide polymorphisms (SNPs) within vascular endothelial growth factor (VEGF) gene and additional gene-environment interaction with renal cell carcinoma (RCC) risk.

METHODS

PCR-restriction fragment length polymorphism was performed to detect SNPs. Hardy-Weinberg equilibrium and allele frequencies in cases and controls were calculated using SNPStats (http://bioinfo.iconcologia.net/SNPstats). Generalized multifactor dimensionality reduction (GMDR) was used to screen the best interaction combination among 4 SNPs, smoking, and alcohol drinking. Logistic regression was performed to investigate the association between 4 SNPs within VEGF gene, additional gene-smoking interaction, and RCC risk.

RESULTS

RCC risk was significantly higher in carriers with the T allele of rs833061 within VEGF gene than those with CC genotype (CT+TT vs. CC) {adjusted odds ratio (OR) (95% confidence interval [CI]) = 1.71 (1.17-2.32), p = 0.002} and higher in carriers with the A allele of rs699947 within VEGF gene than those with GG genotype (GA+AA vs. GG) (adjusted OR [95% CI] = 1.64 [1.27-2.10], p < 0.001). GMDR analysis indicated a significant 2-locus model (p = 0.0010) involving rs833061 and smoking. The cross-validation consistency of the 2-locus model was 10/10, and the testing accuracy was 60.72%. Current smokers with rs833061-CT+TT genotype had the highest RCC risk, compared to never smokers with rs833061-CC genotype within VEGF gene (OR [95% CI] = 3.02 [1.84-4.23], p < 0.001).

CONCLUSIONS

We found that the T allele of rs833061 and the A allele of rs699947 within VEGF gene, and the interaction between rs833061 and smoking were all associated with increased RCC risk.