Producing 14C-Phytoene & Phytofluene for Cancer Research

描述（由申请人提供）：前列腺癌是美国男性癌症死亡的第二大原因。流行病学证据表明，随着番茄制品消费量的增加，前列腺癌的风险降低。番茄含有多种类胡萝卜素，其中一些已被证明具有抗氧化和抗癌作用。最近的研究集中在番茄的主要类胡萝卜素，番茄红素，但很少有研究已经进行了番茄红素，八氢番茄红素和六氢番茄红素的类胡萝卜素生物合成前体。我们推测，除了番茄红素，八氢番茄红素和六氢番茄红素有助于降低前列腺癌的风险。目前还不清楚八氢番茄红素和六氢番茄红素在前列腺中的吸收、代谢和使用情况，因为八氢番茄红素和六氢番茄红素没有商业上的供应。必须开发可靠的方法来生产、分离和分析这些类胡萝卜素。这项工作的总体目标是优化番茄细胞悬浮培养系统，以生物合成14 C-放射性标记的八氢番茄红素和六氢番茄红素的生物利用度，代谢和生物分布的研究，这些类胡萝卜素在动物模型。这项建议的具体目标是：1）通过添加八氢番茄红素去饱和酶抑制剂氟草松，利用体外番茄细胞悬浮培养系统生产14 C-放射性标记的八氢番茄红素和六氢番茄红素，2）优化从番茄细胞悬浮培养物中提取和分离14 C-放射性标记的八氢番茄红素和六氢番茄红素，3）确定生物利用度、代谢、和14 C-放射性标记的八氢番茄红素和六氢番茄红素在F344大鼠模型中的生物分布。这项工作的成果将是新的和可靠的方法来生产和分离14 C-放射性标记的八氢番茄红素和六氢番茄红素的发展，除了确定的积累八氢番茄红素，六氢番茄红素，和它们的代谢产物在前列腺。这些新方法将提供设计动物模型中的体内癌症预防试验和开发用于人类代谢工作的13 C标记类胡萝卜素的能力。

DESCRIPTION (provided by applicant): Prostate cancer is the second leading cause of cancer death in American men. Epidemiological evidence indicates a decreased risk of prostate cancer with increased consumption of tomato products. Tomatoes contain a variety of carotenoids, some of which have been shown to have antioxidant and anticancer effects. Recent research has focused on the primary tomato carotenoid, lycopene, yet few studies have been conducted with the carotenoid biosynthetic precursors of lycopene, phytoene and phytofluene. We hypothesize that in addition to lycopene, phytoene and phytofluene contribute to the reduced risk of prostate cancer. It is unclear how well phytoene and phytofluene are absorbed, metabolized, and made available for use in the prostate, because phytoene and phytofluene are not commercially available. Reliable methods to produce, isolate, and analyze these carotenoids must be developed. The overall objective of this work is to optimize a tomato cell suspension culture system to biosynthesize 14C-radiolabeled phytoene and phytofluene for bioavailability, metabolism, and biodistribution studies of these carotenoids in an animal model. The specific aims of this proposal are: 1) To utilize an in vitro tomato cell suspension culture system to produce both 14C-radiolabeled phytoene and phytofluene through the addition of a phytoene desaturase inhibitor, norflurazon, 2) To optimize the extraction and separation of 14C-radiolabeled phytoene and phytofluene from tomato cell suspension cultures, 3) To determine the bioavailability, metabolism, and biodistribution of 14C-radiolabeled phytoene and phytofluene in the F344, rat model. The outcome of this work will be the development of novel and reliable methods to produce and isolate 14C-radiolabeled phytoene and phytofluene, in addition to determining the accumulation of phytoene, phytofluene, and their metabolites in the prostate. These novel methods will provide the ability to design both an in vivo cancer prevention trial in an animal model and to develop 13C-labeled carotenoids for human metabolic work.