A polymorphic -844T/C in FasL promoter predicts survival and relapse in non-small cell lung cancer.

Abstract

Fas ligand (FasL) -844T/C polymorphism (rs763110) has a demonstrated association with lung cancer risk. FasL -844CC with higher FasL expression has been suggested to contribute to tumor progression via immune escape. However, the impact of FasL -844T/C polymorphism on the clinical outcome of non-small cell lung cancer (NSCLC) remains to be identified. A total of 385 adjacent normal lung tissues from patients with NSCLC were collected to determine FasL -844T/C polymorphism by PCR-based restriction fragment length polymorphism. FasL mRNA and protein expression in lung tumors were evaluated by real-time PCR and immunohistochemistry. The prognostic value of FasL -844T/C polymorphism on survival and relapse was determined by Kaplan-Meier analysis and Cox proportional hazards models. The FasL -844CC genotype had higher prevalence in those with advanced tumors than in those with early tumors (P = 0.008). In addition, patients with the FasL -844CC genotype were more prone to tumor relapse than those with the FasL -844TT+TC genotype (62.1% vs. 37.9%, P = 0.001). Multivariate Cox regression analysis showed that patients with the FasL -844CC genotype had poorer survival in terms of overall survival (OS) and relapse-free survival (RFS) than those with the FasL -844TT+TC genotype (24.1 vs. 42.8 months for OS, HR = 1.455, P = 0.004; 15.4 vs. 31.4 months for RFS, HR = 1.710, P < 0.001). FasL -844T/C polymorphism may predict survival and relapse in NSCLC. We suggest that FasL may be a molecular target for immunotherapeutic interventions to improve the clinical outcome of patients with NSCLC. This finding should be validated by another investigative group.