Genomic Scanning for Genetic and Epigenetic alterations in head and neck cancer

描述（由申请人提供）：这是一个有竞争力的赠款更新“基因组扫描表观遗传和遗传改变在头颈癌”。先前的资助已经成功完成，并产生了大量描述头颈部鳞状细胞癌（HNSCC）中DNA甲基化和DNA扩增改变的数据。在染色体6 q23 -24上鉴定的一种新基因（转录因子21或TCF 21），该区域在HNSCC以及其他恶性肿瘤中经常丢失，具有肿瘤抑制功能以及转移抑制活性。TCF 21是人类肿瘤中改变的DMA甲基化的常见靶标，并且通过DMA甲基化而转录沉默。我们提供的初步数据支持我们的假设，TCF 21是一个新的肿瘤/转移抑制基因。为了解决这一假设，我们提出了三个具体目标。(1)在目标1中，我们将研究TCF 21的表达模式和各种正常组织和癌细胞系中可能的选择性剪接形式，并详细评估DMA甲基化如何有助于DMA沉默。我们接下来将评估HNSCC和肺癌中TCF 21的突变谱，以确定TCF 21沉默在每种肿瘤类型中的重要性。(2)在目标2中，我们提出的实验将有助于了解TCF 21如何促进肿瘤发生，并使用表达阵列，ChIP，酵母双杂交和荧光素酶测定的组合来识别不同组织的特异性结合伴侣和靶基因。(3)在目标3中，我们将利用小鼠模型进一步研究TCF 21的作用。我们正在计划裸鼠致瘤性和转移试验，我们提出了一个致癌实验与Tcf 21杂合子敲除小鼠，并将研究Tcf 21和下游靶点在口腔癌和肺癌的小鼠模型。

DESCRIPTION (provided by applicant): This is a competitive renewal of grant "Genomic Scanning for Epigenetic and Genetic alterations in Head and neck cancer". The previous grant has been successfully completed and resulted in a wealth of data describing altered DMA methylation and DMA amplification in head and neck squamous cell carcinoma (HNSCC). One of the novel genes (transcription factor 21 orTCF21), identified on chromosome 6q23-24, a region frequently lost in HNSCC, as well as other malignancies has tumor suppressor function, as well as metastasis suppressing activity. TCF21 is a frequent target for altered DMA methylation in human tumors and is transcriptionally silenced by DMA methylation. We provide preliminary data supporting our hypothesis that TCF21 is a novel tumor/metastasis suppressor gene. To address this hypothesis, we propose three specific aims. (1) In aim 1 we will investigate expression patterns of TCF21 and possible alternative splice forms in various normal tissues and cancer cell lines and evaluate in detail how DMA methylation contributes to DMA silencing. We will next evaluate the mutational spectrum of TCF21 in HNSCC and lung cancer to determine the importance of TCF21 silencing in each tumor type. (2) In aim 2 we propose experiments that will help to understand how TCF21 contributes to tumorgenesis and identify binding partners and target genes specific for different tissues using a combination of expression array, ChIP, yeast two hybrid and luciferase assays. (3) In aim 3 we will utilize mouse models to further investigate the role of TCF21. We are planning nude mouse tumorigenicity and metastasis assays, we are proposing a carcinogenesis experiment with Tcf21 heterozygous knock out mice; and will investigate Tcf21 and downstream targets in a mouse model for oral cavity carcinogenesis and lung carcinogenesis.