Class III PI3K as an Autophagy Reactivation Switch in Malignant Transformation

III 类 PI3K 作为恶性转化中的自噬重新激活开关

基本信息

批准号：
9565532
负责人：
Lindsey N Young
金额：
$ 3.97万
依托单位：
UNIVERSITY OF CALIFORNIA BERKELEY
依托单位国家：
美国
项目类别：
财政年份：
2017
资助国家：
美国
起止时间：
2017-09-14 至 2019-08-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9565532
关键词：
1-Phosphatidylinositol 3-Kinase Address Affinity Amino Acids Antimalarials Autophagocytosis Biochemical Cancerous Catalytic Domain Cell Culture Techniques Cells Cellular biology Chloroquine Complex Conflict (Psychology)Coupled Cryoelectron Microscopy Dimerization Environment Enzymes Event Goals Homeostasis Human Hydroxychloroquine Hypoxia Immunologic Monitoring Impairment In Vitro Lead Lipids Malignant - descriptor Malignant Neoplasms Malignant neoplasm of pancreas Mass Spectrum Analysis Membrane Metabolic Modification Molecular Molecular Conformation Monitor Neoplasm Metastasis Nutrient Outcome Pathway interactions Pharmaceutical Preparations Phase Phosphorylation Phosphotransferases Play Proliferating Proteins Proteome Regulation Reporting Research Research Project Grants Resolution Role Sampling Signal Transduction Site Stable Isotope Labeling Starvation Stress Structure Therapeutic Translations Tumor Suppressor Proteins Vascular blood supply Work Yeasts anti-cancer cancer cell cancer therapy cell growth design inhibition of autophagy targeted treatment therapeutic target tumor tumor hypoxia

项目摘要

Project Summary Macroautophagy (hereafter autophagy) is crucial to cellular homeostasis. In healthy cells, high levels of basal autophagy are necessary for proper homeostasis and are required for anticancer immunosurveillance. Malignant transformations can arise when autophagy is impaired. Autophagic activity is low until the tumor outpaces its available nutrient supply. As the tumor outgrows its blood supply, the environment become hypoxic, and autophagy re-activation is necessary for tumor proliferation and invasion. Pharmological inhibition of autophagy by antimalarial drug chloroquine leads to tumor regression, however, this drug is not specific to cancerous cells and has many off-target paths. This dual role of autophagy in cancer complicates our ability to target it therapeutically. It is unknown how autophagic function is restored, and this is a central question in the field. All autophagy activation mechanisms involve the lipid kinase class III phosphatidylinositol 3-kinase complex I (PI3KC3-C1) containing tumor suppressor protein BECN1. PI3KC3-C1 is a central initiator, however, its activation mechanism is unknown and this makes it a challenging enzyme to target therapeutically. Discovery of the activation mechanism, at the atomic level, of this central lipid kinase complex through cryo-electron microscopy will greatly aid the ability to rationally design therapeutics to selectively activate or inhibit PI3KC3-C1 at various stages in cancer transformation or proliferation. To identify large-scale changes in the proteome during autophagy reactivation in SILAC (Stable Isotope Labeling with Amino acids in Cell culture) coupled with mass spectrometry will be performed. The objective here is to determine if there is a unique target in proliferating tumors, dependent on a specific autophagy activation mechanism or on a selective autophagy pathway. Ideally, this study would produce new protein candidates to target therapeutically, which would be more specific and less toxic than hydroxychloroquine to treat pancreatic cancers.

项目概要巨自噬（以下简称自噬）对于细胞稳态至关重要。在健康细胞中，高基础自噬水平对于适当的体内平衡是必要的，也是抗癌所必需的免疫监视。当自噬受损时，可能会发生恶性转化。自噬性在肿瘤超过其可用的营养供应之前，活性很低。当肿瘤生长超过其血液时供应，环境缺氧，自噬重新激活是肿瘤发生的必要条件扩散和入侵。抗疟药氯喹对自噬的药理学抑制然而，对于肿瘤消退来说，这种药物对癌细胞并不具有特异性，并且有许多脱靶途径。自噬在癌症中的这种双重作用使我们靶向治疗的能力变得复杂。未知自噬功能如何恢复，这是该领域的核心问题。所有自噬激活机制均涉及脂质激酶 III 类磷脂酰肌醇 3-激酶含有肿瘤抑制蛋白 BECN1 的复合物 I (PI3KC3-C1)。 PI3KC3-C1 是一个中心引发剂，然而，其激活机制尚不清楚，这使其成为一种具有挑战性的目标酶治疗上。在原子水平上发现这种中央脂质激酶的激活机制通过冷冻电子显微镜进行复杂的研究将极大地有助于合理设计治疗方法的能力在癌症转化或增殖的各个阶段选择性激活或抑制 PI3KC3-C1。鉴定 SILAC（稳定）自噬重新激活过程中蛋白质组的大规模变化细胞培养中的氨基酸同位素标记）与质谱联用执行。这里的目标是确定增殖肿瘤中是否存在独特的靶标，依赖于特定的自噬激活机制或选择性自噬途径。理想情况下，这项研究将产生新的候选蛋白质来进行治疗，这将比羟氯喹治疗胰腺癌更具特异性且毒性更小。