Structure, mechanism, and pharmacology of BRAF and its partners in the RAS/RAF/MAP kinase pathway

BRAF 及其 RAS/RAF/MAP 激酶通路伙伴的结构、机制和药理学

• 批准号: 10669154
• 负责人: MICHAEL J ECK
• 金额: $ 104.66万
• 依托单位: DANA-FARBER CANCER INST
• 依托单位国家: 美国
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-09-01 至 2026-08-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10669154
• 关键词: Antineoplastic Agents; BRAF gene; Biochemical; Biophysics; Cancer Etiology; Cell Proliferation; Complex; Confusion; Cryoelectron Microscopy; Drug Targeting; Epidermal Growth Factor Receptor; Exhibits; Goals; Human; Investigation; KRAS2 gene; Knowledge; Laboratories; MAP Kinase Gene; MEKs; Malignant Neoplasms; Mitogen-Activated Protein Kinases; Mutation; New Agents; Pathway interactions; Pharmacology; Phosphotransferases; Protein Kinase; Proteins; Ras/Raf; Regulation; Signal Pathway; Structure; Work; cancer therapy; cell growth; drug discovery; inhibitor; insight; interest; melanoma; mutant; pharmacologic; receptor; reconstitution; resistance mechanism; structural biology; targeted agent; targeted treatment

Abstract The RAS/MAP kinase pathway is aberrantly activated in a wide variety of human cancers. The V600E mutation in BRAF, a kinase in this pathway, causes approximately one-half of all melanomas and is the driver in many other cancers as well. Despite decades of intense interest and investigation, BRAF regulation is not well- understood. Furthermore, compounds targeting the RAS/MAPK pathway exhibit poorly understood pharmacologic effects. BRAF inhibitors, such as vemurafenib, potently inhibit V600E BRAF, but they paradoxically activate wild type BRAF. Inhibitors of MEK, a kinase downstream of BRAF, differ in their efficacy depending upon whether the pathway is activated by mutations in KRAS versus BRAF. Collectively, the confusing pharmacology of these agents reflects our incomplete knowledge of the regulation and biochemical workings of this pathway and limits our ability to develop targeted therapies for BRAF and the RAS/MAPK pathway. Over the last two decades, my laboratory has focused on the structural biology of protein kinases and their dysregulation in cancer, and on cancer drug discovery. We have applied our basic biophysical, biochemical and structural insights into wild-type and mutant EGFR to discover new classes of pharmacologic agents targeting the mutant receptor, including both mutant-selective covalent and allosteric inhibitors that can overcome resistance mechanisms. We are now applying an analogous structural and mechanistic approach to demystify BRAF regulation and pharmacology. Our objectives are to understand BRAF regulation in structural detail, to decipher the complex pharmacology of the BRAF and MEK inhibitors, and to develop new agents that target the pathway in a mutant-selective manner. To achieve these goals, we will determine the structure of autoinhibited and active BRAF complexes using cryo-electron microscopy. We will reconstitute the pathway from KRAS to ERK using purified components in order to dissect mechanisms of BRAF and MEK activation and probe the effects of pharmacologic agents that target the pathway. In addition, we will use these reconstitutions together with our structural insights to discover new agents that target the pathway in a mutant-selective manner. These studies will provide fundamental new understanding of BRAF regulation and, in the long term, they should yield more effective and better tolerated therapies for cancers driven by mutagenic activation of this pathway.

抽象的 RAS/MAP激酶途径在各种各样的人类癌症中被异常激活。 V600E BRAF突变是该途径中的激酶，导致大约一半的黑色素瘤，是驱动器 还有许多其他癌症。尽管有数十年的激烈兴趣和调查，但BRAF监管不是很好 理解。此外，靶向RAS/MAPK途径的化合物表现出鲜为人知的 药理效应。 BRAF抑制剂（例如vemurafenib）有效抑制V600E BRAF，但它们 矛盾地激活野生型BRAF。 BRAF下游的激酶Mek的抑制剂在功效上有所不同 取决于途径是否被KRAS与BRAF中的突变激活。集体， 这些药物的药理学混淆反映了我们对调节和生化的不完整知识 该途径的运作，并限制了我们开发BRAF和RAS/MAPK有针对性疗法的能力 路径。 在过去的二十年中，我的实验室专注于蛋白质激酶的结构生物学和 它们在癌症和癌症药物发现方面的失调。我们应用了基本的生物物理，生化 以及对野生型和突变体EGFR的结构见解，以发现新的药理学剂 靶向突变受体，包括突变选择性共价和变构抑制剂，可以 克服抵抗机制。我们现在正在应用一种类似的结构和机械方法 神秘的BRAF调节和药理学。我们的目标是了解结构性的BRAF调节 细节，破译BRAF和MEK抑制剂的复杂药理学，并开发新的代理商 以突变选择方式靶向途径。为了实现这些目标，我们将确定 使用冷冻电子显微镜自身抑制和活跃的BRAF复合物。我们将重建从 KRAS使用纯化的组件到ERK，以剖析BRAF和MEK激活和探测的机制 针对途径的药理学剂的影响。此外，我们将一起使用这些重构 借助我们的结构见解，可以发现以突变选择方式靶向途径的新药物。这些 研究将为BRAF监管提供基本的新理解，从长远来看，它们应屈服 该途径的诱变激活驱动的癌症更有效，更耐受的疗法。