Background: Various carotenoids in circulation, including isomers, may have different influences on cancer risk. Methods: We conducted a nested case–control study including 343 incident prostate cancer cases and 640 controls individually matched on age, race, study site, and time of blood collection. Carotenoids investigated were carotene, cryptoxanthin, lycopene, dihydrolycopene, lutein, anhydrolutein, and zeaxanthin, including α versus β configurations and cis versus trans isomers. General linear model and conditional logistic regression were applied to evaluate associations for prostate cancer risk, with adjustment for potential confounders. We conducted additional analyses with further stratification by race, multivitamin use, and smoking status. Results: Case–control differences were found in carotenoid subtype levels, although not all reached the multiple comparison adjusted threshold for significance. Plasma lycopene [ORT1 vs. T3 = 0.51; 95% confidence interval (CI), 0.29–0.87; P trend = 0.014], dihydrolycopene (ORT1 vs. T3 = 0.37; 95% CI, 0.18–0.74; P trend = 0.006), and cis -anhydrolutein (ORT1 vs. T3 = 0.57; 95% CI, 0.33–0.96; P trend = 0.037) were inversely, while β- trans -carotene (ORT1 vs. T3 = 2.13; 95% CI, 1.32–3.43; P trend = 0.002) and trans -lutein (ORT1 vs. T3, 1.86; 95% CI, 1.20–2.88; P trend = 0.006) were positively associated with prostate cancer risk. Stratified analyses showed inverse associations of lycopene, dihydrolycopene, and cis -anhydrolutein with prostate cancer risk in subjects without multivitamin use; lycopene and dihydrolycopene in African-Americans and current smokers; and dihydrolycopene in nonsmokers. Positive associations of β- trans -carotene and trans -lutein were observed in African-Americans, nonsmokers, and multivitamin users. Conclusions: The associations of carotenoids with risk of prostate cancer differed by carotenoid subtypes. Impact: Public health recommendations on carotenoid intakes for prostate cancer prevention should take subtypes and isomers into consideration.

中文翻译：

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亚型和异构血浆类胡萝卜素与低收入非洲和欧洲美国人前列腺癌风险的关联


背景：循环中的各种类胡萝卜素，包括异构体，可能对癌症风险有不同的影响。方法：我们进行了一项巢式病例对照研究，包括 343 例前列腺癌病例和 640 例对照，这些病例在年龄、种族、研究地点和采血时间上进行了单独匹配。研究的类胡萝卜素包括胡萝卜素、隐黄质、番茄红素、二氢番茄红素、叶黄素、脱水叶黄素和玉米黄质，包括α与β构型以及顺式与反式异构体。应用一般线性模型和条件逻辑回归来评估前列腺癌风险的关联，并调整潜在的混杂因素。我们进行了额外的分析，按种族、多种维生素的使用和吸烟状况进一步分层。结果：类胡萝卜素亚型水平存在病例对照差异，尽管并非全部达到多重比较调整的显着性阈值。血浆番茄红素 [ORT1 与 T3 = 0.51； 95% 置信区间 (CI)，0.29–0.87； P 趋势 = 0.014]、二氢番茄红素（ORT1 与 T3 = 0.37；95% CI，0.18–0.74；P 趋势 = 0.006）和顺式脱水叶黄素（ORT1 与 T3 = 0.57；95% CI，0.33–0.96；P趋势 = 0.037）相反，而 β-反式-胡萝卜素（ORT1 与 T3 = 2.13；95% CI，1.32–3.43；P 趋势 = 0.002）和反式-叶黄素（ORT1 与 T3，1.86；95% CI， 1.20–2.88；P 趋势 = 0.006）与前列腺癌风险呈正相关。分层分析显示，在未使用多种维生素的受试者中，番茄红素、二氢番茄红素和顺式脱水叶黄素与前列腺癌风险呈负相关；非裔美国人和当前吸烟者中的番茄红素和二氢番茄红素；和非吸烟者中的二氢番茄红素。 在非洲裔美国人、非吸烟者和多种维生素使用者中观察到 β-反式-胡萝卜素和反式-叶黄素呈正相关。结论：类胡萝卜素与前列腺癌风险的关联因类胡萝卜素亚型而异。影响：关于预防前列腺癌的类胡萝卜素摄入量的公共卫生建议应考虑亚型和异构体。