Coordinated regulation of alternative pre-mRNA processing in colon cancer

描述(由申请人提供)：最近的研究记录了与结肠癌相关的替代前信使核糖核酸加工的变化。这些观察表明，异常的前信使核糖核酸加工可能有助于肿瘤的发生。我们已经证明了几种RNA加工因子在结肠癌中的表达水平是错误的，并且Wnt信号转导的Lef/Tcf转录因子的替代mRNA亚型的产生激活了细胞的生长。这些观察结果强烈表明，替代的前mRNA处理参与了结肠癌特有的改变基因表达程序的建立。在这里，我们建议确定在结肠癌中可供选择的前信使核糖核酸加工的程度，并测试结肠癌特异的信使核糖核酸亚型是否为肿瘤的生长和进展提供功能优势。我们将结合实验分析和生物信息学来表征结肠癌特异性的替代前mRNA处理(剪接和多聚腺苷化)。(1)使用高通量测序方法和计算分析，我们将生成结肠癌特异性替代前mRNA加工事件的全面列表。(2)利用mRNA亚型特异的基因敲除和过表达方法，我们将检验这一假说，即mRNA亚型的错误表达改变了结肠癌细胞的表型，并改变了正常结肠维持适当的细胞周期控制的能力。我们还将利用裸鼠结肠癌异种移植模型来检验候选信使核糖核酸亚型表达改变触发肿瘤形成的假设。(3)利用基于细胞的分析和异种移植模型，我们将检验错误调节的前mRNA加工因子影响蛋白质组多样性和结肠癌发生的假说。所描述的实验将突出结肠癌特异性的替代前mRNA处理事件，这可能对开发额外的筛查和结果预测至关重要。此外，了解结肠癌特异性替代前mRNA处理所涉及的机制可能为人类结肠癌的新疗法铺平道路。在整个项目中，我们将依靠我们在癌症生物学、RNA生物学和生物信息学方面的专业知识来获取结肠癌基因表达模式的快照，从而产生对结肠癌研究社区有用的丰富数据。识别结肠癌特异性的替代前mRNA加工事件，结合差异基因表达模式，将对结肠癌的早期发现和改善预后预测具有重要价值。最终，替代的前信使核糖核酸加工分析可能会发现结肠癌治疗的新靶点。

DESCRIPTION (provided by applicant): Recent work has documented that change in alternative pre-mRNA processing associate with colon cancer. These observations suggest that aberrant pre-mRNA processing may contribute to tumorigenesis. We have demonstrated that the expression levels of several RNA processing factors are misregulated in colon cancer and that generation of alternative mRNA isoforms of the Wnt-signaling LEF/TCF transcription factors activates cell growth. These observations strongly suggest that alternative pre-mRNA processing participates in establishing altered gene expression programs that are characteristic for colon cancer. Here we propose to determine the extent of alternative pre- mRNA processing in colon cancer and to test whether colon cancer-specific mRNA isoforms provide a functional advantage for tumor growth and progression. We will combine experimental analyses with bioinformatics to characterize colon cancer-specific alternative pre-mRNA processing (splicing and polyadenylation). (1) Using high throughput sequencing approaches and computational analyses we will generate a comprehensive list of colon cancer-specific alternative pre-mRNA processing events. (2) Using mRNA isoform-specific knockdown and overexpression approaches we will test the hypothesis that the misexpression of mRNA isoforms changes the colon cancer cell phenotype and alters the ability of normal colon to maintain proper cell cycle control. We will also test the hypothesis that the altered expression of candidate mRNA isoforms triggers tumor formation using colon cancer xenograft models in nude mice. (3) Using cell-based assays and xenograft models we will test the hypothesis that misregulated pre-mRNA processing factors influence proteomic diversity and colon tumorigenesis. The experiments described will highlight colon cancer-specific alternative pre-mRNA processing events that may be crucial for the development of additional screening and outcome predictions. Furthermore, understanding the mechanisms involved in colon cancer-specific alternative pre-mRNA processing may pave the way for novel therapies of human colon cancer. Throughout this project we will rely on our expertise in cancer biology, RNA biology, and bioinformatics to obtain snapshots of gene expression patterns in colon cancer, thus producing a wealth of data useful to the colon cancer research community. The identification of colon cancer-specific alternative pre-mRNA processing events coupled with differential gene expression patterns will be valuable for early detection and improved prediction of colon cancer prognosis. Ultimately, the alternative pre-mRNA processing analysis may uncover new targets for colon cancer therapy.