Genetic polymorphisms in oxidative stress-related genes are associated with clinical outcome in patients with advanced non-small cell lung cancer receiving tyrosine kinase inhibitors.

Many types of cancer have high antioxidant capacity that effectively scavenges reactive oxygen species and thus protect cancer cells against oxidative damage. The aim of this study was to examine the effect of 20 single nucleotide polymorphisms (SNPs) in 20 oxidative stress-related genes on clinical outcome in 219 patients with advanced non-small cell lung cancer (NSCLC) who were treated with EGFR tyrosine kinase inhibitors (TKIs). We assessed the associations of SNPs with prognosis in all patients as well as stratified by clinical characteristics. Three SNP (rs1695, rs2333227 and rs699512) were significantly associated with overall survival (OS). In a multivariate analysis, rs1695 AA and rs2333227 AG/GG genotypes were identified as independent prognostic factors for poor OS. Stratification analyses revealed that these 3 SNPs remained significantly associated with OS. Furthermore, there was a strong gene-dosage effect of these 3 SNPs on OS that patients with increasing number of unfavorable genotypes had significantly increased death risk. In conclusion, our findings provide the first evidence that genetic variants in oxidative stress-related genes may influence treatment outcome in advanced NSCLC patients receiving EGFR TKIs.