Influence of vascular endothelial growth factor single nucleotide polymorphisms on non-small cell lung cancer tumor angiogenesis

Vascular endothelial growth factor (VEGF) plays an important role in tumorangiogenesis. Several studies have reported that genomic VEGF polymorphisms mayinfluence VEGF synthesis. To evaluate the role of VEGF single nucleotide polymorphisms(SNPs), we examined the expression of several angiogenesis-related proteins [VEGF,hypoxia-inducible factor-1α (HIF-1α) and delta-like ligand 4 (Dll4)] and the spreadof microvessels in resected non-small cell lung cancer (NSCLC). Blood and tumortissue from 83 patients with NSCLC were examined for VEGF -460T/C (rs833061) andVEGF +405G/C (rs2010963) SNPs using the SNaPshot method. Immunohistochemical stainingwas performed to measure protein expression and microvessel density (MVD). VEGF -460T/Cand +405G/C SNPs showed no association with VEGF or HIF-1α expression and MVD.Patients with VEGF -460TT and the TC genotype had significantly higher MVD comparedto those with the CC genotypes. Furthermore, patients with the VEGF -460TT genotypehad significantly higher Dll4 expression compared to those with the TC or CC genotypes,while the VEGF +405G/C SNP displayed no association with Dll4 expression and MVD.These findings indicate that the VEGF -460T/C SNP may have a functional influenceon tumor angiogenesis in NSCLC. We hypothesize that VEGF SNPs may influence angiogenesisthrough Dll4.