TSER polymorphism is not associated with risk of pediatric acute lymphoblastic leukemia: A meta-analysis

BACKGROUND: Accumulating studies have explored the effect of thymidylate synthase enhancer region (TSER) variation on risk of pediatric acute lymphoblastic leukemia (ALL) with controversial results. Therefore, this quantitative meta-analysis was performed to assess synthetically the association of TSER variation with susceptibility to develop pediatric ALL. METHODS: The PubMed, ScienceDirect, Google Scholar, Wanfang Database, and China National Knowledge Infrastructure were systematically retrieved to obtain the published case-control studies about the relationship between TSER variation and pediatric ALL risk. The quality assessment of the included studies was preformed and relevant information was collected. Odds ratios (ORs) and 95% confidence intervals (CIs) were applied to evaluate the strength of association. RESULTS: This meta-analysis finally included 2681 children with ALL and 3854 matched controls from 11 investigations. The quantitative synthesis results found no significant association between TSER variation and susceptibility to pediatric ALL in overall comparisons under 5 genetic models (2R/3R vs 3R/3R: OR = 0.95, 95% CI = 0.84–1.07, P = 0.41; 2R/2R vs 3R/3R: OR = 0.99, 95% CI = 0.84–1.16, P = 0.90; 2R2R vs 3R/3R+2R/3R: OR = 1.05, 95% CI = 0.92–1.21, P = 0.45; 2R/3R+2R/2R vs 3R/3R: OR = 0.97, 95% CI = 0.87–1.09, P = 0.63; 2R vs 3R: OR = 1.03, 95% CI = 0.92–1.15, P = 0.61). Similarly, there was no significant association existed in the stratification analyses according to ethnicity, control source, and quality score. CONCLUSION: This meta-analysis shows that TSER variation is not related to the development risk of pediatric ALL.