Department of Urology, First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi Zhuang Autonomous Region, People's Republic of China.
Ann Epidemiol. 2010 Feb;20(2):108-21. doi: 10.1016/j.annepidem.2009.10.003.
Sporadic colorectal cancer (CRC) is considered to be a multifactorial disease, in which multiple exposures to endogenous factors interact with individual genetic background in a complex manner, resulting in modulation of the risk. The glutathione S-transferase M1 gene (GSTM1) is a particularly attractive candidate for CRC susceptibility because it codes an enzyme involved in the metabolism of environmental carcinogens. However, the epidemiological findings have been inconsistent.
To evaluate this association, we performed an extensive meta-analysis of 36 case-control studies (including 10,009 cases and 15,070 controls).
Overall, the combined data showed that GSTM1 deficiency is associated with a marginal effect on CRC risk (odds ratio [OR] = 1.13; 95% confidence interval [CI]: 1.03-1.23; P for heterogeneity <0.001). When stratified by race and tumor site, significant results were only observed in Caucasians (OR = 1.14, 95% CI: 1.01-1.27; P for heterogeneity <0.001), whereas no increased risk was detected in other subgroups.
The findings of our study support the suggestion that GSTM1 polymorphism is associated with an increased risk of CRC, especially in the Caucasian population. Further investigation into the association between GSTM1 polymorphism and the risk of CRC is warranted and should include larger sample sizes and other genetic polymorphisms in metabolism of environmental carcinogens.
散发性结直肠癌（CRC）被认为是一种多因素疾病，其中多种内源性因素以复杂的方式与个体遗传背景相互作用，从而调节风险。谷胱甘肽 S-转移酶 M1 基因（GSTM1）是 CRC 易感性的一个特别有吸引力的候选基因，因为它编码一种参与环境致癌物代谢的酶。然而，流行病学研究结果并不一致。
为了评估这种相关性，我们对 36 项病例对照研究（包括 10009 例病例和 15070 例对照）进行了广泛的荟萃分析。
总体而言，合并数据显示 GSTM1 缺失与 CRC 风险呈轻微相关（比值比 [OR] = 1.13；95%置信区间 [CI]：1.03-1.23；异质性 P<0.001）。按种族和肿瘤部位分层时，仅在白种人中观察到显著结果（OR = 1.14，95%CI：1.01-1.27；异质性 P<0.001），而在其他亚组中未检测到增加的风险。
本研究的结果支持 GSTM1 多态性与 CRC 风险增加相关的观点，尤其是在白种人群中。需要进一步研究 GSTM1 多态性与 CRC 风险之间的关联，并应包括更大的样本量和其他环境致癌物代谢中的遗传多态性。
