Colorectal and Anal Surgery Center, The Affiliated Jiangsu Cancer Hospital of Nanjing Medical University, Nanjing, China.
PLoS One. 2012;7(3):e32425. doi: 10.1371/journal.pone.0032425. Epub 2012 Mar 5.
N-Acetyltransferase (NAT) 2 is an important enzyme involved in the metabolism of different xenobiotics, including potential carcinogens, whose phenotypes were reported to be related to individual susceptibility to colorectal cancer (CRC). However, the results remain conflicting. To assess the relationship between NAT2 phenotypes and CRC risk, we performed this meta-analysis.
A comprehensive literature search was conducted to identify all case-control or cohort studies of NAT2 acetylator status on the susceptibility of CRC by searching of PubMed and EMBASE, up to May 20, 2011. Crude odds ratios (ORs) with 95% confidence intervals (CIs) were used to assess the association.
A total of over 40,000 subjects from 40 published literatures were identified by searching the databases. No significantly elevated CRC risk in individuals with NAT2 slow acetylators compared with fast acetylators was found when all studies pooled (OR = 0.95, 95% CI: 0.87-1.04, I(2) = 52.6%). While three studies contributed to the source of heterogeneity were removed, there was still null result observed (OR = 0.96, 95% CI: 0.90-1.03, P = 0.17 for heterogeneity, I(2) = 17.8%). In addition, we failed to detect any associations in the stratified analyses by race, sex, source of controls, smoking status, genotyping methods or tumor localization. No publication bias was observed in this study.
This meta-analysis suggests that the NAT2 phenotypes may not be associated with colorectal cancer development.
N-乙酰基转移酶（NAT）2 是一种参与多种异生物质代谢的重要酶，包括潜在的致癌物质，其表型被报道与个体易患结直肠癌（CRC）的风险有关。然而，结果仍然存在争议。为了评估 NAT2 表型与 CRC 风险之间的关系，我们进行了这项荟萃分析。
通过搜索 PubMed 和 EMBASE，我们对截至 2011 年 5 月 20 日发表的所有关于 NAT2 乙酰化状态对 CRC 易感性的病例对照或队列研究进行了全面的文献检索。使用粗比值比（OR）及其 95%置信区间（CI）来评估相关性。
通过数据库搜索，共确定了来自 40 篇已发表文献的超过 40000 名受试者。当所有研究合并时，NAT2 慢乙酰化个体与快乙酰化个体相比，CRC 风险没有显著升高（OR = 0.95，95%CI：0.87-1.04，I² = 52.6%）。当去除导致异质性的三项研究后，仍然观察到无效结果（OR = 0.96，95%CI：0.90-1.03，P = 0.17 用于异质性，I² = 17.8%）。此外，我们在按种族、性别、对照来源、吸烟状况、基因分型方法或肿瘤定位进行的分层分析中均未发现任何相关性。这项研究没有发现发表偏倚。
这项荟萃分析表明，NAT2 表型可能与结直肠癌的发生无关。
