Masonic Cancer Center, University of Minnesota, Minneapolis, MN, USA.
Masonic Cancer Center, University of Minnesota, Minneapolis, MN, USA.
J Chromatogr B Analyt Technol Biomed Life Sci. 2020 Mar 15;1141:122023. doi: 10.1016/j.jchromb.2020.122023. Epub 2020 Feb 7.
Polycyclic aromatic hydrocarbons (PAH) are well-established environmental carcinogens likely to be causative agents for some human cancers. Bay-region diol epoxides are ultimate carcinogenic metabolites of multiple PAH. Dihydrodiols are the important intermediate products of this pathway and can be further oxidized to form diol epoxides. We quantified two dihydrodiol metabolites of phenanthrene (Phe), the simplest PAH with a bay-region, in the 6 h urine of smokers (N = 25) and non-smokers (N = 25) using a newly developed and validated analytical method. After hydrolysis by ß-glucuronidase and sulfatase, and solid phase extraction, the sample was silylated and analyzed by gas chromatography-negative ion chemical ionization-tandem mass spectrometry (GC-NICI-MS/MS). Levels (nmol/6h urine) of Phe-1,2-dihydrodiol (Phe-1,2-D) and Phe-3,4-dihydrodiol (Phe-3,4-D) were 2.04 ± 1.52 and 0.51 ± 0.35 , respectively, in smokers, significantly higher than those in non-smokers (1.35 ± 1.11 of Phe-1,2-D, p < 0.05; 0.27 ± 0.25 of Phe-3,4-D, p < 0.005). Cigarette smoking also influenced the regioselective metabolism of Phe, presenting as a significant difference in the urinary distribution pattern of Phe-1,2-D and Phe-3,4-D between smokers and non-smokers: the ratio Phe-3,4-D: Phe-1,2-D increased from 0.20 in non-smokers to 0.28 in smokers (p < 0.01), which can be explained by the induction of the phenanthrene metabolizing enzymes CYP1A2 and CYP1B1 by cigarette smoke. The method described here is the first example of facile quantitation of an intact human dihydrodiol metabolite of any PAH with three or more aromatic rings and will be applicable in clinical and molecular epidemiology studies of PAH metabolism and cancer susceptibility.
多环芳烃（PAH）是公认的环境致癌物，可能是某些人类癌症的致病因素。Bay 区域二醇环氧化物是多种 PAH 的最终致癌代谢物。二氢二醇是该途径的重要中间产物，可进一步氧化形成二醇环氧化物。我们使用新开发和验证的分析方法，定量了苯并[a]蒽最简单的 Bay 区域 PAH 中两种二氢二醇代谢物（N = 25）在吸烟者和不吸烟者（N = 25）的 6 小时尿液中的含量。经过β-葡萄糖醛酸酶和硫酸酯酶水解，固相萃取后，样品经硅烷化，用气相色谱-负化学电离-串联质谱（GC-NICI-MS/MS）分析。吸烟者尿液中二氢二醇（Phe-1,2-D）和 Phe-3,4-二醇（Phe-3,4-D）的水平（nmol/6h 尿）分别为 2.04±1.52 和 0.51±0.35，明显高于不吸烟者（Phe-1,2-D 为 1.35±1.11，p<0.05；Phe-3,4-D 为 0.27±0.25，p<0.005）。吸烟也影响苯并[a]蒽的区域选择性代谢，表现为吸烟者和不吸烟者尿液中二氢二醇和二醇分布模式存在显著差异：Phe-3,4-D：Phe-1,2-D 的比值从不吸烟者的 0.20 增加到吸烟者的 0.28（p<0.01），这可以用香烟烟雾对苯并[a]蒽代谢酶 CYP1A2 和 CYP1B1 的诱导来解释。本文所述的方法是首次简便定量任何具有三个或更多芳环的多环芳烃完整人二氢二醇代谢物的方法，将适用于多环芳烃代谢和癌症易感性的临床和分子流行病学研究。
