Murata M, Tagawa M, Watanabe S, Kimura H, Takeshita T, Morimoto K
Division of Epidemiology, Chiba Cancer Center Research Institute.
Jpn J Cancer Res. 1999 Jul;90(7):711-9. doi: 10.1111/j.1349-7006.1999.tb00805.x.
A case-control study was conducted to explore the possible etiologic role of alcohol and aldehyde dehydrogenase 2 (ALDH2) gene among Japanese colorectal cancer patients. Information on their drinking, smoking and dietary habits was collected from 265 colon and 164 rectum cancer patients, and 794 non-cancer patients as a control group. Genotypes of the ALDH2 gene at codon 487, glutamic acid (ALDH21) as a wild-type or lysine (ALDH22) as a mutated type with reduced enzyme activity, were analyzed by polymerase chain reaction in 160 colon and 110 rectum cancer patients and 121 control persons. Univariate analysis with the chi 2 statistical test showed that heavy alcohol drinking (P < 0.01), frequent meat intake (P < 0.001), and irregular (P < 0.01), hasty (P < 0.01) and excessive (P < 0.001) eating habits were associated with the incidence of both colon and rectum cancers, whereas heavier smoking (P < 0.05) and infrequent fish (P < 0.03) and fruit (P < 0.01) intake were solely associated with incidence of rectum cancer. Infrequent green vegetable intake was not correlated with the incidence of colorectal cancer. Multivariate unconditional logistic regression analysis confirmed the association of alcohol consumption (P < 0.01) and meat intake (P < 0.05). Homozygous and heterozygous carriers of ALDH2*2 allele tended to be found in colon (trend P = 0.04) but not in rectum cancer patients compared to controls. Risk elevation for colon cancer due to alcohol consumption was pronounced among the heterozygotes and it was statistically significant especially for distal colon cancer (trend P = 0.02). We conclude that alcohol consumption is a risk factor for colorectal cancer and the risk can be enhanced in ALDH2 heterozygotes.
开展了一项病例对照研究，以探究酒精和乙醛脱氢酶2（ALDH2）基因在日本结直肠癌患者中可能的病因学作用。从265例结肠癌患者、164例直肠癌患者以及794例非癌症患者（作为对照组）收集了他们的饮酒、吸烟和饮食习惯信息。通过聚合酶链反应对160例结肠癌患者、110例直肠癌患者和121名对照者的ALDH2基因第487密码子的基因型进行了分析，其中谷氨酸（ALDH21）为野生型，赖氨酸（ALDH22）为酶活性降低的突变型。采用卡方统计检验进行单因素分析，结果显示，大量饮酒（P < 0.01）、频繁摄入肉类（P < 0.001）以及不规律（P < 0.01）、匆忙（P < 0.01）和过量（P < 0.001）的饮食习惯与结肠癌和直肠癌的发病率均相关，而大量吸烟（P < 0.05）以及不经常摄入鱼类（P < 0.03）和水果（P < 0.01）仅与直肠癌的发病率相关。不经常摄入绿色蔬菜与结直肠癌的发病率无关。多因素非条件逻辑回归分析证实了饮酒（P < 0.01）和肉类摄入（P < 0.05）之间的关联。与对照组相比，ALDH2*2等位基因的纯合子和杂合子携带者在结肠癌患者中更易出现（趋势P = 0.04），而在直肠癌患者中并非如此。饮酒导致结肠癌的风险升高在杂合子中尤为明显，对于远端结肠癌而言具有统计学意义（趋势P = 0.02）。我们得出结论，饮酒是结直肠癌的一个风险因素，并且在ALDH2杂合子中该风险可能会增加。
