TUMOR SUPPRESOR GENE PROMOTER HYPERMETHYLATION FOR DETECTION OF HEAD AND NECK

我们和其他人已经证明，与启动子相关的肿瘤抑制基因的沉默， 超甲基化是许多人类癌症的共同特征。我们发现了几种新的肿瘤 启动子超甲基化灭活的抑制基因，以及用于检测的候选基因 战略布局我们建议继续鉴定和表征鳞状细胞癌中的高甲基化基因， 头颈部癌（HNSCC），并将通过以下方式鉴定新的启动子高甲基化基因：（1）A 候选基因方法基于检测在其他肿瘤中被发现高甲基化的基因或 候选基因的功能结构和生物学特性;（2）寻找候选基因的功能筛选 用去甲基化剂（5-氮杂-脱氧胞苷）处理后上调的基因。新 鉴定出的高甲基化基因将被表征为功能意义和生物活性， 肿瘤进展。我们将应用一种改良的药理学解蔽方法来定义启动子 失活导致对常规化疗药物耐药性的高甲基化基因 和途径（EFGR）导向疗法。候选的高甲基化肿瘤抑制基因将被 通过在体外和体内小鼠模型中转染候选基因在耐药细胞系中验证。 这些基因将在前瞻性试验和回顾性队列中进行验证， 化疗和EGFR途径特异性试剂。新的启动子高甲基化的目标将是 纳入第二个SPORE提案（项目#2），用作早期检测的标记， 对头颈部癌症患者进行监测。

We and others have demonstrated that silencing of tumor suppressor genes associated with promoter hypermethylation is a common feature of many human cancers. We have identified several novel tumor suppressor genes inactivated by promoter hypermethylation, as well as candidate genes for use in detection strategies. We propose continue to identify and characterize hypermethylated genes in squamous cell carcinoma of the head neck (HNSCC) and will identify novel promoter hypermethylated genes by: (1) A candidate gene approach based on testing genes found to be hypermethylated in other tumors or on the functional structure and biologic plausibility of the candidate gene and (2) A functional screen looking for genes that are up-regulated following treatment with demethylating agents (5-Aza-deoxycytidine). Newly identified hypermethylated genes will be characterized for functional significance and biologic activity in tumor progression. We will apply a modified pharmacologic unmasking approach to define promoter hypermethylated genes whose inactivation contributes to drug resistance to conventional chemotherapeutic and pathway (EFGR) directed therapy. Candidate hypermethylated tumor suppressor genes will be validated in drug resistant cell lines by transfection of candidate genes in in vitro and in vivo mouse models. These genes will then be validated in prospective trials and retrospective cohorts treated with conventional chemotherapy and EGFR pathway specific agents. Novel promoter hypermethylatedtargets will be incorporated into a second SPORE proposal (project #2) for use as markers for the early detection and monitoring of patients with head and neck cancer.