CHEMOPREVENTIVE AGENTS--PROVISION OF SOURCE MATERIALS

这项建议的总体长期目标和具体目标涉及具有潜在致癌抑制活性的植物材料的选择、采购和提取。这些材料将用于发现和开发癌症化学预防药物的研究。同时，该项目将为本计划项目中的其他项目提供文献信息服务。用于研究的植物材料的选择将集中在(1)可食用植物，主要是非美国植物；(2)据报道在与癌症化学预防有关的检测中具有活性，但尚未进行化学研究的植物；(3)没有毒性历史和最低水平的植物化学研究；(4)以前没有调查过或调查过的植物物种有可能产生新的化合物。这些候选植物将通过NAPRALERT数据库对天然产品文献的分析来确定。候选植物材料将在田间采集、栽培和/或以商业方式购买。它们将被干燥、碾磨和提取用于生物测定(项目3和4)，然后将决定继续进行生物测定指导的分级，从最有希望的活性线索中分离出新的癌症化学预防药物。这些材料(1-10公斤批次)将被提取并供应给项目2用于有效成分的分离。所有植物材料都将经过鉴定和认证。该项目还将进行植物材料的初步提取和已确认的活性植物化学物质的放大分离。活性化合物(0.05-1.0g尺度)将根据项目2，LC/MS/MS核心制定的方案或从已发表的文献中分离出来，用于评价作用机制或化学预防效率研究(项目3和4)。此外，该项目将对选择用于生物测定直接分级的所有植物进行文献搜索，并将每种植物的已知化学和药理工作汇编并提供给首席调查员和项目负责人。将认真考虑和应用为拟议项目采购和使用的植物材料的产权和知识产权问题，并将采取适当措施，向合作者和植物原料来源国提供互惠(分享利益)。GRANT-P01CA48112-08A1-0002在本计划项目竞争更新申请中，建议继续利用生物活性分级技术，从植物来源中发现新的天然产物，作为潜在的化学致癌抑制剂。在另一项计划中制备的选定的非极性和极性植物提取物在一项计划中的体外分析和在另一项计划中的二次分析中的任一项或两项中都被证明是有效的，将根据公认的植物化学程序进行层析，这样获得的组分由最初证明最大活性的短期体外生物测定来监测。将使用光谱和化学方法来确定纯生物活性化合物的结构。结合文献数据监测和LC/MS/MS核心研究，将努力最大限度地减少对具有已知化学预防活性的化合物的重新分离。因此，预计该项目将继续为新的化学实体提供抑癌活性，以便进行详细的生物学评价。这些自然生成的化合物本身可能具有机械甚至临床价值，或者可以作为本计划项目最后一个项目中后续合成修饰的新的先导化合物。

The overall long term objectives and specific aims of this proposal concern the selection, procurement and extraction of plant materials having potential carcinogenesis inhibitory activity. The materials will be used for studies leading to the discovery and development of cancer chemopreventive agents. At the same time, this project will provide literature information services to the other projects in this Program Project. Selection of plant materials for study will be focused on (1) edible plants, primarily non-USA; (2) plants reported to have activity in an assay pertinent to cancer chemoprevention, but which have not been investigated chemically; (3) plants with no history of toxicity and minimal level of phytochemical studies; and (4) not previous investigated or minimally investigated plant species have the potential to yield novel chemical compounds. These candidate plants will be identified by an analysis of natural products literature with the aid of the NAPRALERT database. The candidate plant materials will be field collected, cultivated and/or commercially purchased. They will be dried, milled, and extracted for bioassay (Projects 3 and 4), and a decision will then be made to proceed with bioassay-directed fractionation for novel cancer chemopreventive agents from the most promising active leads. These materials (1-10 kg lots) will be extracted and supplied to Project 2 for the isolation of the active principles. All plant materials will be identified and authenticated. This project will also perform initial extraction of plant materials and scale-up isolation of confirmed active phytochemicals. The active compounds (0.05 - 1.0 g scale) will be isolated according to protocols developed by Project 2, the LC/MS/MS Core or from published literature, for evaluation of mechanism of action or chemopreventive efficiency studies (Projects 3 and 4). In addition, this project will conduct literature searched on all plants chosen for bioassay directed fractionation, and known chemical and pharmacological work on each of plant will be assembled and provided to the Principal Investigator and the Project Leaders. Issues on property rights and intellectual property rights for plant materials acquired and used for the proposed project will be carefully considered and applied, and appropriate measures will be taken to provide reciprocity (share of benefits) to collaborators and to source countries of the raw plant materials. GRANT-P01CA48112-08A1-0002 In this Program Project competitive renewal application, it is proposed to continue the discovery of novel natural products from plant sources as potential inhibitors of chemical carcinogenesis, using bioactivity- fractionation techniques. Selected non-polar and polar plant extracts prepared in another Program have shown to be active in either or both in vitro assays in a program and secondary assay in yet another program will be chromatographed according to well-established phytochemical procedures, with the fractions so obtained being monitored by the short- term in vitro bioassay in which the greatest activity was originally demonstrated. Spectroscopic and chemical methods will be used to determine the structures of pure bioactive compounds. In concert with literature data surveillance and studies in the LC/MS/MS Core, efforts will be made to minimize the re-isolation of compounds with known chemopreventive activity. Thus, it is expected that this project will continue to provide new chemical entities with cancer inhibitory activity for detailed biological evaluation. Such naturally occurring compounds might have mechanistic or even clinical value per se, or alternatively might serve as new lead compounds for subsequent synthetic modifications in the last project of this Program Project.