Mapping Regulatory Pathways in Cancers

描述（由申请人提供）：我们建议应用微阵列（ChIP ChIP）上的染色质免疫沉淀（Chromatin Immunoprecipitation）新兴技术来鉴定已知参与乳腺癌和结肠癌的转录因子（tf）的直接靶点。在项目的R21阶段，我们计划使用一套新开发的寡核苷酸微阵列来识别这些靶标，该微阵列包含1500万个50mer探针，以100 bp的分辨率通过人类基因组的非重复序列进行扫描。我们将验证我们的ChIP芯片协议与这个新的平铺阵列集一起工作。我们还将开发和完善两种新方案，微阵列重用和四色杂交，这将允许经济地使用这种平铺阵列集，使其成为研究实验室更实用的工具。在这个项目的R33阶段，我们将使用这个排列阵列来确定9个已知与乳腺癌和结肠癌有关的tf的直接靶点。一旦我们收集了这些tf的直接靶标，我们将开发定制的阵列，这些阵列的探针可以遍历直接靶标中的所有结合位点。我们将使用这些聚焦TF的筛选阵列来研究冰岛乳腺癌和结肠癌样本中的结合模式，以确定TF结合模式是否可以作为分类肿瘤的有用手段。

DESCRIPTION (provided by applicant): We propose to apply the emerging technology of Chromatin Immunoprecipitation on microarrays (ChIP chip) to identify the direct targets of transcription factors (TFs) known to be involved in breast and colon cancers. During the R21 phase of the project, we plan to identify these targets using a newly developed set of oligonucleotide microarrays that contain 15 million 50mer probes that tile through the non-repetitive sequence of the human genome at 100 bp resolution. We will validate that our ChIP chip protocols work with this new tiling array set. We will also develop and refine two new protocols, microarray reuse and 4-color hybridizations, that will allow economical use of this tiling array set so that it will be a more practical tool for research labs. In the R33 phase of this project, we will use this tiling array set to identify the direct targets of 9 TFs known to be involved in breast and colon cancers. Once we have collected the direct targets of these TFs, we will develop custom arrays that have probes that tile through all of the binding sites in the direct targets. We will use these TF focused screening arrays to study binding patterns in Icelandic breast and colon cancer samples to determine whether TF binding patterns could be a useful means of classifying tumors.