Ochs-Balcom Heather M, Wiesner Georgia, Elston Robert C
Department of Epidemiology and Biostatistics, Case Western Reserve University, and Ireland Comprehensive Cancer Center at University Hospitals of Cleveland, OH 44106-7281, USA.
Am J Epidemiol. 2007 Aug 1;166(3):246-54. doi: 10.1093/aje/kwm066. Epub 2007 May 29.
The N-acetyltransferase 2 gene (NAT2) product is an enzyme important in carcinogen metabolism via activation and detoxification pathways. Therefore, NAT2 variants may represent underlying susceptibility to breast cancer. Because a number of studies of the association of NAT2 with breast cancer have been published, the authors performed a meta-analysis. They extracted all relevant data to examine evidence for a main effect (i.e., the effect in a model that does not include any interactions) of NAT2 phenotype and genotype on breast cancer risk. They summarized the evidence for modification by smoking and meat intake, sources of exposure to aromatic and heterocyclic amines, respectively, which are metabolized by NAT2. The authors identified seven studies that measured NAT2 phenotype and 20 studies that deduced phenotype via genotyping. They found no evidence for heterogeneity (Cochran's Q statistic p=0.74) and no statistically significant increased risk from NAT2 acetylation (slow/rapid) for breast cancer (summary odds ratio=1.02, 95% confidence interval: 0.95, 1.08). These results suggest that there is no overall association between the NAT2 slow- or rapid-acetylation phenotype and breast cancer risk. However, some evidence suggests that smoking may modify this association.
N - 乙酰基转移酶2基因（NAT2）产物是一种通过激活和解毒途径在致癌物代谢中起重要作用的酶。因此，NAT2变体可能代表乳腺癌的潜在易感性。由于已经发表了许多关于NAT2与乳腺癌关联的研究，作者进行了一项荟萃分析。他们提取了所有相关数据，以检验NAT2表型和基因型对乳腺癌风险的主要效应（即不包括任何相互作用的模型中的效应）的证据。他们总结了分别通过吸烟和肉类摄入量对关联进行修正的证据，吸烟和肉类摄入量分别是NAT2代谢的芳香胺和杂环胺的暴露来源。作者确定了7项测量NAT2表型的研究和20项通过基因分型推断表型的研究。他们没有发现异质性的证据（ Cochr an Q统计量p = 0.74），并且NAT2乙酰化（慢/快）对乳腺癌没有统计学上显著增加的风险（汇总比值比 = 1.02，95%置信区间：0.95，1.08）。这些结果表明，NAT2慢乙酰化或快乙酰化表型与乳腺癌风险之间没有总体关联。然而，一些证据表明吸烟可能会改变这种关联。
