Yang Zhen, Liu Hong-Xiang, Zhang Xie-Fu
Department of Gastrointestinal Surgery, the First Affiliated Hospital of Zhengzhou University, Zhengzhou, China.
Asian Pac J Cancer Prev. 2012;13(5):1923-7. doi: 10.7314/apjcp.2012.13.5.1923.
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.
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).
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.
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.
关于胸苷酸合成酶5'-非翻译增强区（TYMS 5'-UTR）中2R/3R多态性与胃癌风险之间关联的研究结果相互矛盾。因此，进行了一项荟萃分析以总结相关数据。
检索了PubMed、Embase和CNKI数据库中的所有可用研究。通过比值比（OR）及其95%置信区间（CI）评估TYMS 5'-UTR 2R/3R多态性与胃癌风险之间的关联强度。
本荟萃分析纳入了6项个体病例对照研究，共1472例病例和1895例对照。对全部6项相关研究的分析表明，TYMS 5'-UTR 2R/3R多态性与胃癌风险之间无明显关联。基于种族的亚组分析显示，TYMS 5'-UTR 2R/3R的2R等位基因在亚洲人群中增加胃癌风险（纯合子模型OR=1.71，95%CI 1.19-2.46，P=0.004；隐性遗传模型OR=1.70，95%CI 1.18-2.43，P=0.004）。然而，由于研究有限，白种人群中的关联尚不确定。
我们的荟萃分析表明，TYMS 5'-UTR 2R/3R的2R等位基因在亚洲人群中增加胃癌风险，而白种人群中的这种关联需要进一步研究。
