Purpose: This study was conducted to investigate the impact of functional polymorphisms in the FAS and FASL genes on the survival of early stage non-small cell lung cancer (NSCLC) patients.
Experimental design: Three hundred and thirty-eight consecutive patients with surgically resected NSCLC were enrolled. The FAS -1377G>A (rs2234767) and -670A>G (rs1800682) and FASL -844C>T (rs763110) polymorphisms were investigated. Immunohistochemistry was used to assess FAS protein expression in tumors. The genotype and haplotype associations with survival were analyzed using Cox proportional hazards model, Kaplan-Meier method, and the log-rank test.
Results: Patients with the GG and combined AG+GG genotypes of the FAS -670A>G locus had a significantly decreased survival when compared with patients with the AA genotype [adjusted hazard ratio=1.71, 95% confidence interval (95% CI)=1.06-2.77, and P=0.03; and adjusted hazard ratio=1.48, 95% CI=1.01-2.20, and P=0.047, respectively]. In addition, the FAS -1377G/-670G and -1377A/-670G haplotypes exhibited a significantly lower survival compared with the -1377G/-670A haplotype (adjusted hazard ratio=1.87, 95% CI=1.20-2.91, and P=0.006; and adjusted hazard ratio=1.31, 95% CI=1.05-1.65, P=0.02, respectively). Strongly positive FAS immunostaining was significantly less frequent in patients with the FAS -670 AG+GG genotype than in patients with the -670 AA genotype (4.5% versus 10.8%; P=0.04).
Conclusion: The FAS -670A>G polymorphism may affect survival in early-stage NSCLC. The analysis of the FAS -670A>G polymorphism can help identify patients at high risk for a poor disease outcome.