雌激素受体基因多态性、膳食大豆摄入与乳腺癌患病风险的关系

Gene Polymorphism of Estrogen Receptor,Dietary Soy Intake and Breast Cancer Risk

目的：评价雌激素受体α（ estrogen receptor α, ERα）基因XbaⅠ酶切片段多态性（ XbaⅠ多态性）、膳食大豆摄入与乳腺癌患病风险的关系。方法：采用病例对照研究设计,序贯收集病例对照各291例。采用问卷调查收集乳腺癌常见危险因素信息；采用频次调查及单次摄入量调查,收集膳食大豆类食物摄入情况,并转换为大豆异黄酮日摄入量。采用限制性片段长度多态性技术,检测XbaⅠ（rs9340799）A→G（x→X）基因突变。采用多因素Logistic回归分析XbaⅠ多态性、膳食大豆摄入的主效应和交互效应,并计算相乘交互系数。采用delta原理计算相加交互系数及其可信区间。结果：在总人群及绝经前后亚组中,携带X突变等位基因与乳腺癌患病风险无关（ Xx vs. xx：OR=0.61~0.82；XX vs. xx：OR=0.60~3.62； Xx＋XX vs. xx： OR=0.61~0.92,95%CI均包括1）。膳食大豆高摄入对乳腺癌具有保护作用（总人群：OR=0.64,95%CI：0.42~0.97；绝经后：OR=0.40,95%CI：0．19~0.81）。总人群中,携带X等位基因且膳食大豆高摄入进一步降低乳腺癌风险（ OR=0.47,95%CI：0.25~0．89）。两者相乘交互系数IOR=1.15,95%CI：0.49~2.76；相加交互系数RERI=0.19,95%CI：-0.35~0.73；API=0.41,95%CI：-0.75~1.57；S=0.73,95%CI：0.34~1.59。结论：膳食大豆摄入可能会降低乳腺癌风险,但ERα基因XbaⅠ酶切片段多态性位点X等位基因与膳食大豆高摄入之间是否存在交互作用尚需进一步探讨。

Objective： To assess the association between estrogen receptor α genes XbaI polymorphisms, dietary soy intake and breast cancer. Methods：A case-control study was designed. A total of 291 pairs were sequentially collect-ed. Questionnaires were used to obtain the common risk factors of breast cancer. Daily intake of soy isoflavone （ DISI） was collected by food frequency survey combined with investigation of every intake. Restricted fragment length polymorphisms were used to examine XbaⅠ（rs9340799） A→G （x→X）. Multiple logistic regression model was used to evaluate the sin-gle and interactive effects of XbaⅠpolymorphism and DISI. Multiplication interaction coefficient was also calculated. Based on the delta theory, the interaction coefficients of additive model with 95% CI were calculated. Results：There was no as-sociation between XbaⅠpolymorphism and breast cancer among general women and menopausal subgroups（ Xx vs. xx：OR= 0. 61~0. 82;XX vs. xx：OR=0. 60~3. 62;Xx＋XX vs. xx：OR= 0. 61~0. 92, all the 95%CIs included 1）. High multiplication interaction coefficient IOR=1. 15, 95% CI： 0. 49 ~2. 76. The interaction coefficients of additive model were as follows：RERI=0. 19, 95%CI： -0. 35~0. 73;API=0. 41, 95% CI： -0. 75~1. 57;S=0. 73, 95% CI：0. 34~1. 59. Conclusion： High intake of soy could reduce breast cancer risk. However, the interaction between estrogen receptor α genes XbaI polymorphisms and soy intake needs to be further explored.