Department of Radiation Oncology, Sichuan Cancer Hospital, Chengdu 610041, Sichuan Province, PR China.
Gene. 2013 Sep 15;527(1):275-82. doi: 10.1016/j.gene.2013.06.042. Epub 2013 Jun 27.
Many studies have investigated the association between the Glutathione S transferase-P1 (GSTP1) Ile105Val polymorphism and colorectal cancer (CRC) susceptibility, but the results were conflicting. The aim of this study is to quantitatively summarize the relationship between this polymorphism and CRC risk.
Two investigators independently searched the Medline, Embase, China National Knowledge Infrastructure (CNKI) and Chinese Biomedicine databases for studies published before December 2012. Summary odds ratios (ORs) and 95% confidence intervals (95% CIs) for GSTP1 polymorphism and CRC were calculated in a fixed-effects model (the Mantel-Haenszel method) and a random-effects model (the DerSimonian and Laird method) when appropriate.
This meta-analysis included 29 case-control studies, which included 8160 CRC cases and 10,450 controls. Overall, the variant genotypes (ValVal and IleVal) of the Ile105Val were not associated with CRC risk when compared with the wild-type IleIle homozygote. Similarly, no associations were found in the dominant and recessive models. When stratifying for ethnicity, source of controls, study sample size and genotyping methods, no evidence of significant association was observed in any subgroup, except among those studies taking others as genotyping methods (recessive model, OR=0.71, 95%CI=0.52-0.96). Limiting the analysis to the studies within Hardy-Weinberg equilibrium, the results were persistent and robust. No publication bias was found in the present study.
This updated meta-analysis suggests that the GSTP1 Ile105Val polymorphism may not be associated with CRC risk, while the observed decrease in risk of CRC may be due to small-study bias.
许多研究已经调查了谷胱甘肽 S-转移酶-P1（GSTP1）Ile105Val 多态性与结直肠癌（CRC）易感性之间的关系，但结果存在矛盾。本研究的目的是定量总结这种多态性与 CRC 风险之间的关系。
两名调查人员分别独立检索了 Medline、Embase、中国国家知识基础设施（CNKI）和中国生物医学数据库，以获取截至 2012 年 12 月发表的研究。在适当的情况下，使用固定效应模型（Mantel-Haenszel 方法）和随机效应模型（DerSimonian 和 Laird 方法）计算 GSTP1 多态性和 CRC 的汇总优势比（OR）和 95%置信区间（95%CI）。
这项荟萃分析包括 29 项病例对照研究，共包括 8160 例 CRC 病例和 10450 例对照。总体而言，与野生型 IleIle 纯合子相比，Ile105Val 的变异基因型（ValVal 和 IleVal）与 CRC 风险无关。同样，在显性和隐性模型中也没有发现关联。按种族、对照来源、研究样本量和基因分型方法进行分层，除了那些以外的研究作为基因分型方法（隐性模型，OR=0.71，95%CI=0.52-0.96），在任何亚组中都没有发现有意义的关联的证据。将分析限制在符合 Hardy-Weinberg 平衡的研究中，结果是持续和稳健的。本研究未发现发表偏倚。
本更新的荟萃分析表明，GSTP1 Ile105Val 多态性可能与 CRC 风险无关，而 CRC 风险的降低可能归因于小样本研究偏差。
