Kinome-Wide Spectroscopic Study of Drug Binding Site Electrostatics

描述（由申请人提供）：蛋白激酶在调节细胞生长和增殖的信号通路中发挥核心作用，激酶活性异常有助于许多癌症的发展。最近用靶向蛋白激酶抑制剂治疗特定癌症的成功，特别是肺癌和慢性髓系白血病，强调了这些蛋白在肿瘤发生中的重要性，并强调了需要额外的激酶抑制剂来治疗其他癌症。开发新的激酶抑制剂具有挑战性，因为激酶atp结合位点（这些小分子的主要靶向位点）的高序列保守性使得很难获得对特定激酶具有选择性的化合物。目前的研究旨在通过一种全新的实验方法来解决这个问题，这种方法利用了物理化学的进步。在Aim 1中，一种称为振动斯塔克光谱的新光谱技术将用于构建atp结合位点的静电图，以及它在该蛋白家族的约500个成员中如何变化。这些测量将使用具有电场振动探针的激酶抑制剂进行，其中探针报告了当它们结合在ATP结合位点时所经历的静电。由于这些静电图与ATP结合位点的物理环境如何从抑制剂的角度出现有关，因此它们将直接了解抑制剂化学结构的变化如何影响与激酶的相互作用。在这些测量中发现的激酶之间的差异可以用来设计更具选择性的药物。在Aim 2中，这种可能性将通过进行大规模结合试验来量化，其中激酶抑制剂面板的选择性将被揭示，并直接与静电测量相比较，以揭示静电变化如何决定选择性。而选择性分析是司空见惯的

DESCRIPTION (provided by applicant): Protein kinases play central roles in the signaling pathways that regulate the growth and proliferation of cells, and aberrant kinase activity contributes to the development of many cancers. Recent success in treating particular cancers with targeted protein kinases inhibitors, notably lung cancer and chronic myeloid leukemia, underscores the importance of these proteins in oncogenesis, and highlights the need for additional kinase inhibitors to treat other cancers. The development of new kinase inhibitors is challenging because the high sequence conservation of the kinase ATP-binding site, the major site targeted by these small molecules, makes it difficult to obtain compounds that are selective for particular kinases. The current study aims to address this problem through an entirely new experimental approach that utilizes advances in physical chemistry. In Aim 1, a new spectroscopic technique called vibrational Stark spectroscopy will be used to construct a map of the electrostatics of the ATP-binding site and how it varies across the ~500 members of this protein family. These measurements will be made using kinase inhibitors that possess vibrational probes of electric field, in which the probes report on the electrostatics they experience when bound in the ATP- binding site. Because these electrostatic maps relate to how the physical environment in the ATP- binding site appears from the perspective of the inhibitors, they will yield direct insight into how changes to the chemical structure of the inhibitors would affect the interaction with kinases. Differences uncovered between kinases in these measurements could be exploited to design more selective drugs. In Aim 2, this possibility will be quantified by performing large-scale binding assays in which the selectivity of panels of kinase inhibitors will be revealed and directly compared to the electrostatics measurements to reveal how electrostatic variation dictates selectivity. While selectivity profiling is commonplace in the pharmaceutical industry, the comparison with the electrostatic maps determined in Aim 1 will allow the physical basis of inhibitor selectivity to be determined for the first time, guidingthe way to the development of inhibitors with new selectivity profiles. In Aim 3 the characterization of the ATP-binding site will be completed by studying how this environment is affected by the dynamic rearrangements of protein groups and bound water molecules. The protein kinases now constitute a major group of pharmacological targets, and taken together this work will constitute the first comprehensive experimental study of how the physical properties of these proteins dictate their interaction with drug molecules. PUBLIC HEALTH RELEVANCE: Cancer is one of the primary causes of death in the developed world, and for most patients treatment revolves mainly around the use of non-selective cytotoxic drugs, in addition to radiation therapy and surgery. Recent dramatic success in the treatment of several types of cancer with kinase inhibitors has demonstrated that a different approach, which selectively targets the molecular anomaly responsible for the disease, has many advantages. This project will study the physical principles that govern the ability of drugs to selectivity target particular protein kinases, potentially leading to new treatments for cancers caused by mutated protein kinases.