Identifying Mitophagy Receptors as Targets in Ras-dysregulated Cells

鉴定线粒体自噬受体作为 Ras 失调细胞的靶标

• 批准号: 10215731
• 负责人: Michael Joseph Ragusa
• 金额: $ 30.9万
• 依托单位: DARTMOUTH COLLEGE
• 依托单位国家: 美国
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-09-01 至 2021-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10215731
• 关键词: Accounting; Alleles; Autophagocytosis; Catabolic Process; Cell Culture Techniques; Cells; Development; Dissection; Family; Genes; Goals; Guanosine Triphosphate Phosphohydrolases; Institutes; KRAS2 gene; Malignant Neoplasms; Mammalian Cell; Mitochondria; Mutation; Neoplastic Cell Transformation; Oncogenic; Pancreatic Ductal Adenocarcinoma; Pathway interactions; Process; Publications; Reagent; Role; Structure; Survival Rate; Testing; Therapeutic; Toxic effect; United States; Up-Regulation; cell transformation; genetic approach; inhibitor/antagonist; mouse model; novel; pancreas development; preference; prevent; receptor; recruit; response; small molecule inhibitor; targeted treatment; tumorigenesis

The five year survival rate for pancreatic ductal adenocarcinomas (PDAC) is approximately 5% making it one of the most lethal cancers in the United States. Despite the fact that more than 90% of PDAC contain activating mutations within the gene encoding the GTPase KRas, the development of small-molecule inhibitors for KRas has only been successful for the G12C allele accounting for 3% of KRAS mutations in PDAC. As such, inhibiting pathways which are essential for KRas-driven transformation and tumorigenesis may provide a more promising avenue for the development of PDAC targeted therapies. One such pathway that is upregulated in response to oncogenic KRas expression encompasses a set of catabolic processes termed autophagy. Indeed, a wealth of indicative publications suggest that autophagy could represent an Achilles’ heel for certain aggressive and intractable cancers, and inhibitors that globally block autophagy have shown some promise in cell culture and mouse models of PDAC. However, therapeutic concentrations of these autophagy inhibitors resulted in toxicity. Further translational progress has been hampered by the lack of specific reagents: autophagy is actually not a single process but rather a broad family of pathways with distinct cargo preferences and mechanisms of recruitment. Recently, oncogenic KRasG12V expression, which accounts for 30% of KRAS mutations in PDAC, has been shown to result in the upregulation of a specialized form of autophagy, termed mitophagy, in which specific mitophagy receptors mark mitochondria for degradation. The goal of this proposal is to determine the role of mitophagy in KRasG12V transformation and PDAC. Our central hypothesis is that KRas dysregulation leads to the upregulation of mitophagy to promote neoplastic transformation. To test this hypothesis we have developed two specific aims. Aim 1 will determine which of the known mitophagy receptors are required for KRasG12V transformation. Furthermore, in mammalian cells, many of these pathways are redundant, preventing facile dissection in transformed cells. Aim 2 will leverage a novel combination of structural and genetic approaches to identify novel mitophagy receptors and cognate interaction partners and thus explore mechanisms of mitophagy in Ras-dysregulated

胰腺导管腺癌（PDAC）的五年生存率约为5％ 在美国最致命的癌症中。尽管事实是，超过90％的PDAC包含 编码GTPase Kras的基因中激活突变，小分子的发展 KRAS的抑制剂仅在G12C等位基因上成功，占KRAS突变的3％ PDAC。因此，抑制对KRAS驱动转化和肿瘤发生必不可少的途径 可以为开发PDAC靶向疗法提供更有承诺的途径。这样的道路 响应于致癌性KRAS表达的响应中，这包括一组分解代谢过程 称为自噬。确实，大量的指示性出版物表明自噬可能代表 阿喀琉斯的脚跟，用于某些侵略性且顽固的癌症，以及全球障碍的抑制剂 在PDAC的细胞培养和小鼠模型中表现出了一些希望。但是，治疗浓度 在这些自噬抑制剂中，导致毒性。进一步的翻译进展受到了 缺乏特定的试剂：自噬实际上不是一个过程，而是一个广泛的途径家庭 具有独特的货物偏好和招募机制。最近，致癌Krasg12v表达， 占PDAC中KRAS突变的30％，已证明会导致A上调 专业形式的自噬形式，称为线粒体，其中特定的线粒体受体标记线粒体 用于退化。该建议的目的是确定线粒体在KRASG12V转换中的作用 和PDAC。我们的中心假设是KRAS失调导致线粒体上调至 促进肿瘤转化。为了检验这一假设，我们开发了两个具体的目标。目标1意志 确定KRASG12V转换需要哪些已知的线粒体接收器。此外，在 哺乳动物细胞，其中许多途径是冗余的，可防止转化的细胞中的易于剖析。 AIM 2将利用结构和遗传方法的新型组合来识别新型线粒体 受体和同源相互作用伙伴，从而探索RAS偏离的线粒体机制