Molecular Pathogenic Mechanism of Rhabdomyosarcoma

横纹肌肉瘤的分子发病机制

• 批准号: 8157684
• 负责人: Liang Cao
• 金额: $ 25.47万
• 依托单位: DIVISION OF BASIC SCIENCES - NCI
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/8157684
• 关键词: Binding; Data; Data Set; Embryonic Development; FGFR4 gene; Genetic Enhancer Element; IGF1R gene; Molecular; PAX3 gene; PAX7 gene; Rhabdomyosarcoma; Validation

To understand the molecular pathogenic mechanism of PAX3-FKHR in the development of RMS, we used ChIP-seq to map PAX3-FKHR genomic binding sites associated with 1072 genes in RMS cells. I. The data shows that PAX3-FKHR binds to the same sites as PAX3 at enhancers for MYF5, FGFR4, as well as the MYOD core enhancer previously shown to be downstream of PAX3 regulation. Moreover, our dataset has the precision for a rapid identification and validation of novel and specific sequences required for the enhancer activity for MYOD and FGFR4. II. The genome wide analysis reveals that the vast majority of PAX3-FKHR sites are: 1) distal to transcription start sites; 2) conserved; 3) enriched for PAX3 motifs; 4) strongly associated with genes over-expressed in PAX3-FKHR positive RMS cells and tumors. There is little evidence in our dataset for PAX3-FKHR binding at the promoters. In one instance, our data establishes two intronic enhancer elements for MET, rather than at the previously described promoter. The genome-wide analysis further illustrates a strong association between PAX3 and E-box motifs in these binding sites, suggestive of a common co-regulation for many target genes. III. The map of PAX3-FKHR binding sites provides new links for PAX3 and PAX3-FKHR functions and new targets for RMS therapy. Our study identifies genes that are critically important for different aspects of limb-genesis, as direct PAX3-FKHR targets. Further, we identify IGF1R as a direct target for PAX3-FKHR. The dependence on IGF1R for survival in some RMS cells with PAX3-FKHR makes it an ideal therapeutic target for this cancer.

为了了解 PAX3-FKHR 在 RMS 发展中的分子致病机制，我们使用 ChIP-seq 绘制了与 RMS 细胞中 1072 个基因相关的 PAX3-FKHR 基因组结合位点。 I. 数据显示，PAX3-FKHR 与 MYF5、FGFR4 增强子以及先前显示为 PAX3 调节下游的 MYOD 核心增强子处的 PAX3 结合位点相同。此外，我们的数据集具有快速识别和验证 MYOD 和 FGFR4 增强子活性所需的新颖和特定序列的精确度。 二.全基因组分析表明，绝大多数 PAX3-FKHR 位点位于：1) 转录起始位点的远端； 2）保守； 3) 富集PAX3基序； 4)与PAX3-FKHR阳性RMS细胞和肿瘤中过度表达的基因密切相关。我们的数据集中几乎没有证据表明 PAX3-FKHR 在启动子处结合。在一种情况下，我们的数据为 MET 建立了两个内含子增强子元件，而不是在之前描述的启动子处。全基因组分析进一步说明了这些结合位点中 PAX3 和 E-box 基序之间的紧密关联，表明许多靶基因存在共同的共同调控。 三． PAX3-FKHR 结合位点图谱提供了 PAX3 和 PAX3-FKHR 功能的新链接以及 RMS 治疗的新靶点。我们的研究确定了对肢体发生的不同方面至关重要的基因，作为直接的 PAX3-FKHR 靶标。此外，我们确定 IGF1R 是 PAX3-FKHR 的直接靶标。一些带有 PAX3-FKHR 的 RMS 细胞的存活依赖于 IGF1R，这使其成为这种癌症的理想治疗靶点。