中文摘要：

目的探讨微小RNA（miR）-146a基因多态性与胃肠癌易感性的关系。方法通过计算机检索PubMed、Medline及Ovid全文数据库、中国期刊网全文数据库（CNKI）、万方数据库及中国生物医学文献数据库中公开发表的关于miR-146a与胃癌或结直肠癌易感性的相关文献，检索时限为2010年7月至2014年3月。采用改良Jadad质量评分对文献进行质量评价，采用Stata11．0软件对数据进行分析，计算比较等位基因（G与C）、显性遗传模型（GC＋GG与CC）、隐性遗传模型（GG与GC＋CC）、纯合子（GG与CC）和杂合子（GC与CC）5种不同基因型OR值，来评估miR-146a多态性与胃肠癌发生的关系。结果共16篇文献纳入研究，其中病例组7090例，对照组9928例。Meta分析显示，具有等位基因G的人群比等位基因C更易患癌（胃癌：OR=1．10，95％U：1．04～1．17，P=0．001；结直肠癌：OR=I．09，95％CI：1．01～1．18，P=0．020）；显性遗传模型（GC＋GG）比CC更易患胃癌（OR=1．12，95％U：1．02～1．22，P=-0．016），而结直肠癌易感性相当（P=0．068）；隐性遗传模型GG比（CC＋GC）更易患癌（胃癌：OR=1．16，95％凹：1．05～1．27，P=0．004；结直肠癌：OR=1．13，95％a：1．00。1．28．P=0．047）；纯合子GG比CC更易患癌（胃癌：OR=1．20，95％U：1．06～1．35，P=0．003；结直肠癌：OR=1．19，95％U：1．01—1．41，P=-0．042）；杂合子GC与CC的患癌易感性相当（P〉0．05）。结论miR-146a的基因多态性与胃癌和结直肠癌之间存在显著关联。

英文摘要：

Objective To investigate the association between microRNA （miR）-146a gene polymorphisms and susceptibility to gastrointestinal cancer. Methods PubMed, Medline and Ovid full text databases, China Journal Full-text Database （CNKI）, Articles Database and Chinese Biomedical Literature Database were researched to retrieved literatures about the association between miR-146a gene polymorphism and susceptibility to gastrointestinal cancer published from July 2010 to March 2014. Modified Jadad quality score was used to evaluate the quality of the literatures and Stata 11.0 software was used to analyze and calculate OR value of the following 5 different genotypes： allele （G vs. C）, the dominant genetic model（GC＋GG vs. CC）, a recessive genetic model （GG vs. GC＋CC） and homozygote （GG vs. CC） and heterozygote （GC vs. CC） to assess the association. Results A total of 16 studies were enrolled, including 7090 cancer patients and 9928 healthy controls. Meta-analysis showed that people with G allele was more susceptible to gastrointestinal cancer than those with C （gastric cancer：OR =1.1,95% CI： 1.04-1.17, P=0.001, colorectal cancer： OR =1.09,95% CI： 1.01-1.18, P=0.020） ; dominant model （GC＋GG） was more susceptible to gastric cancer than CC （OR=I.12, 95% CI： 1.02- 1.22, P=0.016）; recessive genetic model GG was more susceptible to gastrointestinal cancer than CC＋ GC （gastric cancer： OR=1.16, 95% CI： 1.05-1.27, P=0.004, colorectal cancer： OR=1.13, 95%CI： 1.00-1.28, P=-0.047） ; GG homozygote was more susceptible to gastrointestinal cancer than CC （gastric cancer： OR=1.20, 95% CI：1.06-1.35, P=0.003, colorectal cancer： OR=l.19, 95% CI：1.01-1.41, P=0.042）. Dominant genetic model GC＋GG and CC in colorectal cancer as well as heterozygous GC and CC in gastrointestinal cancer were not significantly different（P〉0.05）. Conclusion miR-146a cancer susceptibility gene polymorphism is closely associated with gastrointestinal cancers.