Department of Cancer Biomedical Science, National Cancer Center Graduate School of Cancer Science and Policy, Goyang, Korea.
Center for Colorectal Cancer, National Cancer Center, Goyang, Korea.
Epidemiol Health. 2023;45:e2023100. doi: 10.4178/epih.e2023100. Epub 2023 Nov 14.
Previous human trials have not supported the anticarcinogenic effect of vitamin E despite biological plausibility and considerable epidemiological evidence. A possible explanation for this inconsistency is the interactive effect of the catechol-O-methyltransferase (COMT) gene and supplemental vitamin E on cancer. We examined whether a COMT gene variant modulates the effect of dietary vitamin E intake on colorectal cancer (CRC) risk.
In this case-control study of Korean adults (975 cases and 975 age- and sex-matched controls), dietary vitamin E density (mg/1,000 kcal) was measured using a semiquantitative food frequency questionnaire, COMT single nucleotide polymorphism (SNP) rs740603 (A>G) was genotyped, and CRC was verified histologically. We estimated odds ratios (ORs) and 95% confidence intervals (CIs) using unconditional logistic regression models with adjustments for potential confounders.
Higher vitamin E density was associated with a lower risk of CRC (highest vs. lowest quartiles: OR, 0.72; 95% CI, 0.55 to 0.96; p-for-trend=0.002). When stratified by COMT SNP rs740603 genotype, the inverse association between vitamin E density and CRC risk was confined to those with at least 1 A allele (≥median vs. <median: OR, 0.63; 95% CI, 0.51 to 0.78). The interaction between rs740603 and vitamin E density was significant (p-for-interaction=0.020). No direct association was observed between COMT SNP rs740603 and CRC risk (OR, 1.08; 95% CI, 0.83 to 1.41).
Our findings support a role for a genetic polymorphism in COMT in modifying the association between dietary vitamin E intake and CRC.
尽管有生物学上的合理性和相当多的流行病学证据，但之前的人体试验并未支持维生素 E 的抗癌作用。这种不一致的一个可能解释是儿茶酚-O-甲基转移酶（COMT）基因和补充维生素 E 对癌症的相互作用效应。我们研究了 COMT 基因变异是否调节饮食维生素 E 摄入对结直肠癌（CRC）风险的影响。
在这项针对韩国成年人（975 例病例和 975 例年龄和性别匹配的对照）的病例对照研究中，使用半定量食物频率问卷测量饮食维生素 E 密度（mg/1000 千卡），COMT 单核苷酸多态性（SNP）rs740603（A>G）进行基因分型，并通过组织学验证 CRC。我们使用非条件逻辑回归模型估计了比值比（ORs）和 95%置信区间（CIs），并进行了潜在混杂因素的调整。
较高的维生素 E 密度与 CRC 风险降低相关（最高与最低四分位数相比：OR，0.72；95%CI，0.55 至 0.96；p 趋势=0.002）。按 COMT SNP rs740603 基因型分层时，维生素 E 密度与 CRC 风险之间的负相关仅局限于至少携带 1 个 A 等位基因的人群（≥中位数与<中位数相比：OR，0.63；95%CI，0.51 至 0.78）。rs740603 与维生素 E 密度之间的交互作用具有统计学意义（p 交互=0.020）。COMT SNP rs740603 与 CRC 风险之间没有直接关联（OR，1.08；95%CI，0.83 至 1.41）。
我们的研究结果支持 COMT 基因多态性在调节饮食维生素 E 摄入与 CRC 之间的关联方面的作用。
