title: Lack of association between cytotoxic T-lymphocyte antigen-4 -318C/T polymorphism and cancer risk: a meta-analysis of case-control studies.
abstract: Cytotoxic T-lymphocyte antigen-4 (CTLA-4) is important for the down regulation of T-cell activation. Number of studies assessed the association between CTLA-4 -318C/T polymorphisms and cancer in different populations. However, the studies have provided conflicting results. We performed a meta-analysis to examine the association between CTLA-4 -318C/T polymorphisms and cancer susceptibility. Eligible studies were identified by searching several databases for relevant reports published up to September 30, 2012. Sixteen eligible studies with a total of 6190 patients and 6560 controls were included to summarize the association between CTLA-4 -318C/T polymorphisms and the risk of cancer. Odds ratios (ORs) with 95% confidence intervals (CIs) were used to assess the strength of associations. Overall, no significant associations were found in all genetic models when all studies were pooled into the meta-analysis (for -318C/T polymorphisms as estimated using a fixed effect model: TT vs. (CC + CT), OR = 1.02, 95% CI = 0.83-1.24; (TT + CT) vs. CC, OR = 1.20, 95% CI = 1.00-1.44; TT vs. CC, OR = 1.09, 95% CI = 0.74-1.59; CT vs. CC, OR = 1.21, 95% CI = 1.00-1.46). In further subgroup analyses for the -318C/T polymorphisms, stratified by design of ethnicity, cancer types, solid tumors to non-solid tumors, epithelial tumors to non-epithelial tumors, no significant associations were found in any subgroup of the population. This meta-analysis strongly suggests that -318C/T polymorphisms in CTLA-4 are not associated with an increased risk of cancer.
authors.affiliation: Institute of Genetic Engineering, Southern Medical University, Guangzhou, People's Republic of China. weneli0626@126.com.
authors.forename: Wei
authors.initials: W
authors.lastname: Xia
authors.forename: Rong
authors.initials: R
authors.lastname: Shi
authors.forename: Wen-Ling
authors.initials: WL
authors.lastname: Zheng
authors.forename: Wen-Li
authors.initials: WL
authors.lastname: Ma
mesh_terms: D060908:CTLA-4 Antigen / Q000235:genetics*; D016022:Case-Control Studies; D056726:Genetic Association Studies; D020022:Genetic Predisposition to Disease; D006801:Humans; D009369:Neoplasms / Q000235:genetics*; D020641:Polymorphism, Single Nucleotide; D012307:Risk Factors
chemical_list: D060908:CTLA-4 Antigen; C556706:CTLA4 protein, human