2R of thymidylate synthase 5'-untranslated enhanced region contributes to gastric cancer risk: a meta-analysis.
BACKGROUND
Studies investigating the association between 2R/3R polymorphisms in the thymidylate synthase 5'-untranslated enhanced region (TYMS 5'-UTR) and gastric cancer risk have generated conflicting results. Thus, a meta-analysis was performed to summarize the data on any association.


METHODS
Pubmed, Embase, and CNKI databases were searched for all available studies. The strength of association between TYMS 5'-UTR 2R/3R polymorphism and gastric cancer risk was estimated by odds ratios (ORs) with 95% confidence intervals (CIs).


RESULTS
Six individual case-control studies with a total of 1,472 cases and 1,895 controls were included into this meta-analysis. Analyses of total six relevant studies showed that there was no obvious association between the TYMS 5'-UTR 2R/3R polymorphism and gastric cancer risk. Subgroup analyses based on ethnicity showed 2R of TYMS 5'-UTR 2R/3R contributes to gastric cancer risk in the Asian population (ORHomozygote model=1.71, 95%CI 1.19-2.46, P=0.004; ORRecessive genetic model=1.70, 95%CI 1.18-2.43, P=0.004). However, the association in Caucasian populations was uncertain due to the limited studies.


CONCLUSIONS
Our meta-analysis suggests that 2R of TYMS 5'-UTR 2R/3R contributes to gastric cancer risk in the Asian population, while this association in Caucasians populations needs further study.
Department of Gastrointestinal Surgery, the First Affiliated Hospital of Zhengzhou University, Zhengzhou, China. dryangzzu@126.com
Zhen
Z
Yang
Hong-Xiang
HX
Liu
Xie-Fu
XF
Zhang
D020121:5' Untranslated Regions / Q000235:genetics*; D016022:Case-Control Studies; D020022:Genetic Predisposition to Disease; D006801:Humans; D011110:Polymorphism, Genetic / Q000235:genetics*; D011379:Prognosis; D013274:Stomach Neoplasms / Q000201:enzymology / Q000209:etiology*; D013940:Thymidylate Synthase / Q000235:genetics*
D020121:5' Untranslated Regions; D013940:Thymidylate Synthase