细胞色素P450 2E1基因PstI/RsaI多态性与结直肠癌易感关系的Meta分析

背景:CYP2EI基因是该酶系重要的编码基因之一,有关CYP2E1基因多态性与结直肠癌易感性关系研究较多,但结果存在一定的差异。目的:探讨细胞色素P4502E1基因PstI/RsaI单核苷酸多态性与结直肠癌易感性的关系。方法:检索EMBASE、PubMed、Ovid、Highwire press等西文生物医学文献数据库;CNKI、CBM、万方数据库等中文数据库。获取发表的CYP2E1基因PstI/RsaI单核苷酸多态性与结直肠癌易感性关系的研究。病例组及对照组CYP2E1等位基因分布的比值比为效应指标,根据异质性检验结果选择随机效应模型或固定效应模型对OR进行合并。结果与结论:按照文献入选标准共查到9篇病例对照研究,其中病例组4760例,对照组5812例。以野生型纯合子为参照,评估突变纯合子患结直肠癌的风险OR=1.24(OR=1.24,95%CI:0.93~1.66,P=0.15);以野生纯合子加突变杂合子为参照,评估突变纯合子患结直肠癌的风险OR=1.26(OR=1.26,95%CI:0.94~1.68,P=0.12);以野生纯合子为参照,评估突变纯合子加突变杂合子患结直肠癌的风险OR=1.00(OR=1.00,95%CI:0.90~1.12,P=0.97)。亚组分析,按不同种族分为高加索人群和东亚人群,除高加索人群在c1c1vs.c2c2模式下显示CYP2E1基因PstI/RsaI单核苷酸多态性与结直肠癌易感性有关(OR=2.67,95%CI:1.03~6.89,P=0.04),其他各种模式下Meta分析结果均未显示与结直肠癌易感性有关。说明整体上CYP2E1基因PstI/RsaI单核苷酸多态性与结直肠癌易感性间不存在明显相关性,但高加索人群中携带c2c2突变基因型的个体可能是结直肠癌的易感人群。

Meta-analysis of the relationship between PstI/RsaI polymorphism of cytochrome P450 2E1 gene and colorectal cancer susceptibility

BACKGROUND: Cytochrome P450 2E1 gene (CYP2E1) is one of the important encoding genes in its enzyme system. There are many studies on the relationship between CYP2E1 polymorphism and colorectal cancer susceptibility. However the results have some difference. OBJECTIVE: To explore the relationship between CYP2E1 PstI/RsaI single neucleotide polymorphism and colorectal cancer susceptibility. METHODS: Studies on the relationship between CYP2E1 PstI/RsaI single neucleotide polymorphism and colorectal cancer susceptibility were obtained by searching EMBASE database, PubMed database, Ovid database, Highwire press database, CNKI database, CBM database and Wanfang database. The odds ratio (OR) of CYP2E1 allele of the case group and control group was taken as effective index. Fixed or random effect Meta-analysis model was used to calculate the combined OR. RESULTS AND CONCLUSION: A total of 9 case-control studies containing 4 760 patients and 5 812 controls were included according to inclusion criteria. Evaluation of risk of rectal cancer in mutation homozygote when wild homozygote was used as reference: OR=1.24 (OR=1.24, 95% confidence interval (CI): 0.93-1.66, P=0.15); Evaluation of risk of rectal cancer in mutation homozygote when wild homozygote and mutation homozygote were used as reference: OR=1.26 (OR=0.94, 95%CI: 0.94-1.68, P=0.12); Evaluation of risk of rectal cancer in mutation homozygote and wild homozygote when wild homozygote was used as reference: OR=1.00 (OR=1.00, 95%CI: 0.90-1.12, P=0.97). Sub-group analysis: the studies were divided into Caucasian populations and East Asian populations; Only the Caucasian populations showed a relationship between CYP2E1 PstI/RsaI single neucleotide polymorphism and colorectal cancer susceptibility in the c2c2 VS c1c1 model (OR=2.67, 95%CI: 1.03-6.89, P=0.04). It is indicated that there is no close relationship between CYP2E1 PstI/RsaI single neucleotide polymorphism and colorectal cancer susceptibility except the Caucasian in c2c2 VS c1c1 model.