Cancer Epidemiology Biomarkers & Prevention, 2011, 20(3):419-27.

Plasma isoflavones and the risk of lung cancer in women: a nested case-control study in Japan

Taichi Shimazu, et al

Epidemiology and Prevention Division, Research Center for Cancer Prevention and Screening, National Cancer Center, Tokyo, Japan

BACKGROUND: Although several epidemiologic studies have found that isoflavone intake assessed by questionnaire is associated with a decreased risk of lung cancer, no prospective study has investigated this association using blood concentrations of isoflavones.

METHODS: We conducted a nested case-control study within a population-based prospective cohort study. A total of 24,127 women aged 40 to 69 years who returned the baseline questionnaire and provided blood samples were observed from 1990 through 2006. During a median follow-up period of 13.5 years, 126 newly diagnosed lung cancer cases were identified. For each case, we selected two controls matched for age, area, smoking status, and condition of blood draw. A conditional logistic regression model was used to estimate the odds ratios (ORs) and 95% CIs of lung cancer in relation to plasma concentrations of genistein, daidzein, glycitein, equol, and total isoflavones.

RESULTS: After exclusion of 20 lung cancer cases diagnosed in the first 3 years after blood collection, an inverse association was found between plasma genistein concentration and lung cancer risk. The multivariate-adjusted OR (95% CI) of lung cancer in the highest quintile of plasma genistein concentration as compared with that in the lowest quintile was 0.31 (0.12, 0.86; P for trend=0.085). Other isoflavones and total isoflavones were not associated with a significant decrease in the risk of lung cancer.

CONCLUSION: Plasma genistein concentration was inversely associated with lung cancer risk in Japanese women.

美国《癌症流行病学生物标记物及预防》，2011年1月

血浆异黄酮和女性患肺癌的风险︰ 日本的一项巢式病例对照研究

太极岛津等

日本国立癌症中心癌症预防和筛选技术研究中心流行病学和预防部

背景︰ 虽然几项流行病学研究发现，通过问卷调查估计，异黄酮的摄入与肺癌风险降低相关，但是没有前瞻性研究使用异黄酮的血药浓度来探究这种关联。

方法︰ 我们进行了一项基于人口的巢式病例-对照前瞻性研究。共有 24,127 名年龄在 40 到 69 岁之间的妇女归还了基线调查表并提供了从 1990 年到 2006 年的血液标本。在随访期间 13.5 年的中位，确诊了126 例初诊病例的肺癌。对于每一种情况，我们选择了两个控制条件来匹配地区、 年龄、 吸烟状况和血画的条件。一个Log回归模型被用来估计优势比 (ORs) 和涉及到染料木素、 大豆苷元、 黄豆黄素、 雌马酚，总异黄酮的血浆浓度 95%肺癌患者的CIs。

结果︰ 在第一次 3 年血液采集后排除 20 例诊断的肺癌病例后，发现在金雀异黄素血浆浓度与肺癌风险之间存在负相关。罹患肺癌多元调整的OR (95% CI) 染料木黄酮血浆浓度的最高的五分位数比最低的五分位数是 0.31 （0.12，0.86； P = 0.085)。其他异黄酮和总异黄酮与患肺癌风险的明显降低没有关系。

结论︰染料木黄酮血浆浓度与日本妇女患肺癌的风险成反比。