Inhibition of Protein-Protein Contacts in VEGF Transcription by Synthetic Helices

描述(申请人提供)：血管生成，即程序性生长的血管，受到许多特定的有丝分裂因子的严格控制，其中血管内皮生长因子(VEGF)及其受体起着核心作用。血管内皮生长因子的水平在广泛的肿瘤中上调，并参与癌症生物学的关键方面。作为许多癌症的标志，慢性缺氧与某些致癌信号通路的激活共同导致了血管内皮生长因子水平的升高，并与侵袭和能量代谢改变有关。由于严格控制低氧诱导基因的表达对细胞的生存至关重要，因此首要的目标是开发控制肿瘤细胞中低氧诱导基因的方法，而不影响正常细胞。为了解决这个目标，我们试图发现专门调控低氧诱导转录的合成分子。我们假设，转录过程可以通过破坏关键的转录因子-共激活因子相互作用而得到有效的调控，该相互作用涉及蛋白质p300的CH1结构域或同源CBP和缺氧诱导因子1的C末端反式激活结构域(C-TAD)。这种复合体在界面上具有短的(-螺旋)结构域，表明这些螺旋的合成模拟物将调节蛋白质-蛋白质的相互作用。在本应用中，我们利用了一类新的具有二级结构的人工(-螺旋)，它模仿了HIF-1(C-TAD)的生物学相关片段。在初步研究中，我们已经表明，Hif-1(/p300与我们的合成螺旋相互作用的中断导致细胞培养中重要的低氧诱导基因的快速下调，包括血管内皮生长因子。我们的具体目标是：(1)设计和合成人工螺旋作为转录因子-辅活化子复合体的抑制剂；(2)评估每个抑制剂与其蛋白质靶标的结合热力学，测试它们在体外抑制同源蛋白-蛋白质相互作用的能力；(3)测试人造螺旋干扰肿瘤中HIF诱导基因转录的能力，并从分子水平探索这种干扰的机制细节。将这三个目标结合起来，将验证我们的假设，并为开发一类新的基于结构和机制的癌症疗法奠定基础。 与公共卫生的相关性人类基因组的测序和蛋白质组学的最新进展使人们更好地了解了基因含量和疾病之间的关系。因此，开发基于控制疾病细胞基因表达的新疗法已成为一个日益重要的目标。通过将化学合成技术与分子生物学和遗传学方法相结合，我们的目标是发现在癌症中作为低氧诱导转录抑制因子的独特特定小分子，长期目标是开发治疗有氧糖酵解和血管生成的新疗法。

DESCRIPTION (provided by applicant): Angiogenesis, the programmed growth blood vessels, is tightly controlled by a number of specific mitogenic factors, among which vascular endothelial growth factor (VEGF) and its receptors play a central role. The levels of VEGF are up-regulated across a broad range of tumors and are involved in key aspects of cancer biology. A hallmark of many cancers, chronic hypoxia, in conjunction with activation of certain oncogenic signaling pathways, is responsible for the elevated levels of VEGF and is associated with invasion and altered energy metabolism. Because tight control of hypoxia-inducible gene expression is critical for cellular existence, the goal of primary importance has been to develop methods of controlling hypoxia-inducible genes in malignant cells while leaving normal cells unaffected. To address this goal, we seek to uncover synthetic molecules that specifically regulate hypoxia-inducible transcription. We hypothesize that the process of transcription could be effectively modulated via disruption of key transcription factor-coactivator interactions involving CH1 domain of protein p300 or the homologous CBP and the C-terminal transactivation domain (C-TAD) of the hypoxia-inducible factor 1(. This complex features short (-helical domains at the interface and suggests that synthetic mimics of these helices would modulate the protein-protein interaction. In this application, we utilize a new class of artificial (-helices with secondary structure that mimics the biologically relevant fragment of HIF-1( C-TAD. In preliminary studies, we have shown that disruption of the Hif-1(/p300 interaction with our synthetic helices results in rapid downregulation of important in cancer progression hypoxia-inducible genes, including VEGF, in cell culture. Our specific aims are to: (1) to design and synthesize artificial helices as inhibitors of the transcription factor-coactivator complex; (2) evaluate binding thermodynamics of each inhibitor toward their protein targets, test their ability to inhibit the cognate protein-protein interaction in vitro, and (3) test the ability artificial helices to disrupt transcription of HIF-inducible genes in cancer and explore the mechanistic details of this disruption at the molecular level. Combined these three aims will validate our hypothesis and create a foundation for the development of a new class of structure and mechanism-based cancer therapeutics. PUBLIC HEALTH RELEVANCE The sequencing of the human genome and recent advances in proteomics have led to a better understanding of the relationship between genetic content and disease. As a result, the development of novel therapies based on controlling gene expression in diseased cells has become an increasingly important goal. By combining the art of chemical synthesis with the methods of molecular biology and genetics, we aim to uncover uniquely specific small molecules that act as suppressors of hypoxia-inducible transcription in cancer with the long-term goal of developing new therapeutics for treatment of aerobic glycolysis and angiogenesis.