Mechanisms of FIP200 regulation of breast cancer through its autophagy and non-autophagy functions

FIP200通过自噬和非自噬功能调控乳腺癌的机制

• 批准号: 9927485
• 负责人: JUN-LIN GUAN
• 金额: $ 36.71万
• 依托单位: UNIVERSITY OF CINCINNATI
• 依托单位国家: 美国
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-06-15 至 2022-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9927485
• 关键词: Ablation; Acute; Alleles; Animal Model; Apoptosis; Autophagocytosis; BRCA1 gene; Binding; Biological Process; Breast Cancer Cell; Breast Cancer Model; Breast Cancer therapy; Breast Epithelial Cells; Breast cancer metastasis; Cancer Relapse; Cell physiology; Cells; Characteristics; Complement; Complex; DNA Sequence Alteration; Data; Development; Disease; Embryo; Epidermal Growth Factor Receptor; Family; Goals; Growth; Health; Homeostasis; Human; Impairment; Incidence; Knock-in; Knock-in Mouse; Knowledge; Laboratories; Maintenance; Malignant Neoplasms; Mammary Neoplasms; Mediating; Modeling; Molecular; Mutant Strains Mice; Mutate; Mutation; Neoplasm Metastasis; PTK2 gene; Patients; Play; Population; Property; Proteins; Recurrent disease; Regulation; Relapse; Role; Signal Transduction; Starvation; Stat3 Signaling Pathway; System; TNF gene; Transforming Growth Factor Beta 2; Transforming Growth Factor beta; Tumorigenicity; Woman; aldehyde dehydrogenases; antitumor effect; base; breast cancer progression; conditional mutant; genetic analysis; genetic approach; immune function; in vivo; insight; malignant breast neoplasm; mouse genetics; mouse model; mutant; neoplastic cell; novel; novel therapeutics; response; stem-like cell; targeted treatment; tool; transforming growth factor beta3; tumor; tumor growth; tumor progression; tumorigenic

Breast cancer is the most common malignancy among US women and remains a major health threat with high incidence and lethality. Despite the remarkable progress made recently in deciphering the genetic mutations associated with breast cancer, our understanding of the mechanistic basis for metastasis and relapse of breast cancer is still very limited. The long-term goal of the proposed studies is to understand the molecular and cellular mechanisms involved in these properties of breast cancer cells that are ultimately responsible for patient lethality. FIP200 (FAK-family Interacting Protein of 200 kDa) was initially identified in our laboratory and subsequently shown to be a component of the ULK1/Atg13/FIP200 complex essential for the induction of autophagy. We have shown recently that FIP200 ablation inhibited the development and progression of breast cancer, providing the first evidence of a pro-tumorigenic role for autophagy in animal models with intact immune functions. We also developed an inducible system to delete FIP200 after tumor development in vivo and demonstrated that acute disruption of autophagy by FIP200 deletion in established tumors blocked their growth. In preliminary studies, we identified two distinct populations of breast cancer stem-like cells (BCSCs) and showed that FIP200 ablation impaired the maintenance and tumorigenicity of both BCSCs. Our preliminary data implicated TGF-β/Smad and EGFR/Stat3 signaling pathways in mediating FIP200 regulation of these two BCSCs respectively. In another set of preliminary studies, we identified residues 582-585 in FIP200 for binding to Atg13 and generated a new FIP200 knock-in mutant mouse with these residues mutated to Ala (designated as KI allele, encoding FIP200-4A lacking binding to Atg13). Analysis of KI/KI mice and MEFs derived from KI/KI embryos showed both autophagy and non-autophagy functions of FIP200 in regulating different biological processes. These studies further revealed a new non-autophagy function of FIP200 to protect normal and transformed MEFs from TNFα-induced apoptosis. Thus this unique mutant KI allele as well as additional mouse models prepared in preliminary studies provides us with powerful tools for the genetic analysis of mechanisms of FIP200 regulation of breast cancer through its autophagy and non-autophagy functions in vivo. Based on these strong preliminary data and using our unique novel mouse models, we propose to 1) determine the mechanisms of FIP200 regulation of CD29hiCD61+ and ALDH+ BCSCs in PyMT and BRCA1-deficient mouse models of breast cancer; 2) examine autophagy and non-autophagy functions of FIP200 in the regulation of BCSCs and breast cancer development and progression; and 3) explore the strategies of targeting FIP200 autophagy and non-autophagy functions in BCSCs for breast cancer therapy. Together, these studies will provide significant insights into the molecular and cellular mechanisms of breast cancer metastasis and relapse that may contribute to novel therapies for this devastating disease.

乳腺癌是美国妇女中最常见的恶性肿瘤，仍然是主要的健康威胁 高事件和致命性。尽管最近在解密遗传方面取得了显着进展 与乳腺癌相关的突变，我们对转移机械基础的理解和 乳腺癌的复发仍然非常有限。拟议研究的长期目标是了解 乳腺癌细胞的这些特性涉及的分子和细胞机制，最终是 负责患者致死性。最初在我们的 实验室，随后证明是ULK1/ATG13/FIP200复合物的组成部分 诱导自噬。我们最近表明，FIP200消融抑制了发展和 乳腺癌的进展，提供了自噬在动物中促肿瘤作用的第一个证据 具有完整免疫功能的模型。我们还开发了一个可诱导系统来删除肿瘤后删除FIP200 在体内开发，并证明了FIP200删除在已建立的急性破坏自噬 肿瘤阻止了它们的生长。在初步研究中，我们确定了两个不同的乳腺癌种群 干细胞（BCSC），表明FIP200消融损害了两者的维持和肿瘤性 BCSC。我们的初步数据实施了介导的TGF-β/SMAD和EGFR/STAT3信号通路 FIP200这两个BCSC的调节。在另一组初步研究中，我们确定了 残基582-585在FIP200中与ATG13结合，并与新的FIP200敲入突变小鼠一起使用 这些残留物突变为ALA（指定为Ki等位基因，编码FIP200-4A缺乏与ATG13结合的FIP200-4A）。分析 源自ki/ki胚胎的ki/ki小鼠和MEF，显示了自噬和非自助型功能的 FIP200在不同的不同生物过程中。这些研究进一步揭示了一种新的非自助噬菌 FIP200的功能可保护正常和转化的MEF免受TNFα诱导的凋亡。这个独特的 突变Ki等位基因以及在初步研究中准备的其他鼠标模型为我们提供了强大的 通过自噬和 非自助噬功能在体内。基于这些强大的初步数据，并使用我们独特的新颖鼠标 模型，我们建议1）确定CD29HICD61+和ALDH+ BCSC的FIP200调节机制 在PYMT和BRCA1缺陷小鼠的乳腺癌模型中； 2）检查自噬和非自噬 FIP200在BCSC的调节以及乳腺癌发育和进展中的功能； 3） 探索针对BCSC的fip200自噬和非自助噬功能的策略 治疗。总之，这些研究将提供有关分子和细胞机制的重要见解 乳腺癌转移和缓解可能有助于这种破坏性疾病的新疗法。