Carcinogen Metabolism Enzyme Expression in Buccal Cells

描述(由申请人提供)： 这项建议的具体目标是评估使用基因的有效性 在颊上皮细胞中的表达以准确反映人肺的基因表达 当两者都暴露在烟草烟雾中时，就像吸烟者一样。的归纳 同时编码致癌物质代谢酶的基因 容易获得的代孕组织和肺表明 吸烟者表达生物活性基因表型的可能性 诱导性。如果这种致癌物代谢途径确实与肺有关 癌症易感性，然后是高I相酶和低II相酶 诱导性表型可能被认为是肺癌的危险因素。 肺癌致癌物代谢基因诱导的研究进展 到目前为止，受招收的科目数量的限制，作为优质的人 适合用于表达或活动分析的肺组织供不应求。 此外，对这些基因编码序列多态的研究 在增加肺癌风险方面，呈现了非常复杂的结果。本研究 建议利用新开发的实时方法 量化适当的烟雾暴露的上皮细胞中的基因表达，以及 将该表达与精确定义的显微解剖中的表达进行比较 烟雾暴露的人肺上皮细胞。因此，具体目标是：1) 建立实时荧光定量RT-PCR检测基因的方法 一组致癌物代谢酶在颊粘膜中的表达 包括AhR、ER、CyP1B1、CyP1A1、GSTM1、GSTM3、GSTP1、GSTT1、NQO1。2)比较颊粘膜和同期采集的血浆中的基因表达 用最先进的LC-MS-MS技术检测尼古丁和可替宁。3) 定量比较致癌物质代谢酶基因的表达 从原位烟草暴露的人颊粘膜细胞中分离出 显微解剖的人肺、支气管和肺泡上皮细胞也暴露在 在原地。4)测量这个口腔细胞的变异性 致癌物代谢基因在个体中的表达，占 表达混杂因素，如烟草烟雾暴露和饮食 成分，从而识别第一阶段和第二阶段的高或低 表现者。长期目标是开发一组生物标记物 易接触的烟雾暴露的上皮细胞，识别吸烟者 肺癌的高风险，从而允许戒烟， 化学预防和早期疾病检测战略将重点放在 最危险的情况。

DESCRIPTION (provided by applicant): This proposal's specific objective is to evaluate the validity of using gene expression in buccal cells to accurately reflect gene expression in human lung when both are tobacco smoke-exposed, as they are in smokers. The induction of genes encoding carcinogen metabolizing enzymes simultaneously in an easily-accessible surrogate tissue as well as the lung suggests the possibility of expression phenotyping smokers for bioactivating gene inducibility. If this carcinogen metabolism pathway is indeed relevant to lung cancer susceptibility, then a high phase I and low phase II enzyme inducibility phenotype might be hypothesized to confer risk for lung cancer. The power of studies on carcinogen-metabolizing gene induction in lung cancer to date have been limited by the number of subjects enrolled, as quality human lung tissues suitable for expression or activity assays are in short supply. Additionally, studies of coding sequence polymorphisms in these genes have presented very mixed results as to conferred risk for lung cancer. This study proposes to take advantage of newly developed real-time methods for quantifying gene expression in an appropriate, smoke-exposed epithelium, and comparing that expression to that in precisely-defined microdissected smoke-exposed human lung epithelia. Therefore, the specific aims are: 1) Develop quantitative real-time RT-PCR assays for the evaluation of gene expression of a panel of carcinogen metabolizing enzymes in buccal mucosa, including Ahr, ER, CYP1B1, CYP1A1, GSTM1, GSTM3, GSTP1, GSTT1, NQO1. 2) Compare the gene expression in buccal mucosa to simultaneously sampled plasma assayed for nicotine and cotinine by state-of-the-art LC-MS-MS techniques. 3) Quantitatively compare the expression of carcinogen metabolizing enzyme genes from in situ tobacco-exposed human buccal mucosal cells with that from microdissected human lung bronchial and alveolar epithelial cells also exposed in situ. 4) Measure the variability of this buccal cell carcinogen-metabolizing gene expression across individuals, accounting for expression confounders such as tobacco smoke exposure and dietary constituents, and thereby identify phase I and phase II high or low expressors. The long-term goal is to develop a panel of biomarkers in an easily-accessible, smoke-exposed epithelium that identifies smokers at high-risk for lung cancer, and thereby allows smoking-cessation, chemoprevention and early-disease detection strategies to be focussed on those most at risk.