Cytotoxic T-lymphocyte antigen-4 +49G/A polymorphism and susceptibility to pancreatic cancer

Although pancreatic cancer has been extensively studied, few risk factors have been identified. Cytotoxic T-lymphocyte antigen-4 (CTLA-4) plays important roles in downregulating T-cell activation, thereby attenuating antitumor responses and increasing cancer susceptibility. The CTLA-4 gene +49G/A polymorphism (rs231775) has been reported to be associated with various cancers. The current study evaluated the association of the CTLA-4 gene +49G/A polymorphism with pancreatic cancer in the Chinese population. Six hundred and two pancreatic cancer patients and 651 healthy controls were investigated for CTLA-4 +49G/A polymorphism by polymerase chain reaction-restriction fragment length polymorphism analysis. Data showed that prevalence of CTLA-4 gene +49 AA genotype and +49 A allele was significantly higher in pancreatic patients compared to controls (odds ratio [OR]=2.20, 95% confidence interval [CI]: 1.23-2.95, p=0.007; OR=1.32, 95% CI: 1.03-1.69, p=0.029; and OR=1.47, 95% CI: 1.03-2.09, p=0.033). These results indicate that the CTLA-4 +49G/A polymorphism is associated with increased risk of pancreatic cancer.