The role of the CCR4-NOT complex in the regulation of Nuclear Pore Complex assembly

项目摘要 癌症仍然是全世界死亡的主要原因。尽管作出了重大努力， 尽管开发了有效的治疗方法，但许多类型的肿瘤的存活率仍然很低。的长期目标 这项工作的F99和K00阶段都将揭示导致新型抗癌疗法的新策略。 F99阶段将专注于癌症生物学的细胞内在方面，而K00阶段将专注于癌症生物学的细胞内在方面。 免疫细胞具有直接抑制肿瘤生长和调节已批准的 癌症免疫疗法 F99期：越来越多的证据表明，许多癌细胞会产生成瘾性 核运输机械和核孔复合体（NPC）的数量增加，多- 调节分子核质运输的蛋白质结构。最近的研究表明， 抑制NPC的组装可以代表癌症治疗的有效靶点。但 调节NPC组装的分子因子还不完全清楚，并且靶向途径还没有 被识别。进行全基因组siRNA筛选以找到调节这些基因的组装的基因。 结构.基因被确定，当敲除时，增加或减少细胞表面的NPC含量。 核的表面。发现CCR4-NOT复合物的3个成员的敲除增加NPC。的 CCR4-NOT是一种主要的去腺苷酶复合物，通过调节细胞中mRNA代谢来控制蛋白质水平。 真核生物这里提出的工作将表征CNOT敲除对NPC的影响 数量/功能以及这些变化如何改变基本的细胞生理学。此外，这项工作将阐明 CCR4-NOT复合物调控NPC的分子机制。 K00期：近年来，免疫肿瘤学疗法，即免疫检查点阻断剂， 显示出显著的临床疗效，然而只有一小部分患者对治疗有反应。之一 缺乏疗效的根本原因是存在强烈的免疫抑制肿瘤 微环境（TME）。在TME被改造成更具免疫激活性的环境之前，免疫 检查点阻断疗法将具有有限的成功。该项目的K00阶段将侧重于一个独特的 和动态白细胞，强烈有助于观察到的免疫抑制;肿瘤相关的 巨噬细胞（TAM）。TAM已被证明占肿瘤质量的50%，并且具有促肿瘤生长和抗肿瘤作用。 抗肿瘤表型。仍然需要开发更有效的策略来靶向这种细胞类型， K00研究将描述可以利用来调节的转录网络， TME中的巨噬细胞复极化。 F99期的成功完成将揭示癌症的可靶向细胞内在方面 K00阶段的完成将揭示免疫肿瘤学靶向途径。

PROJECT SUMMARY Cancer continues to be a leading cause of death worldwide. Despite significant efforts devoted towards developing effective treatments, the survival rates remain low in many types of tumors. The long-term goal of both the F99 and K00 phases of this work will be to reveal new strategies that lead to novel anti-cancer therapies. The F99 phase will be focused on a cell-intrinsic aspect of cancer biology, while the K00 phase will focus on an immune cell with great potential to directly inhibit tumor growth and to modulate the efficacy of already approved cancer immunotherapies. The F99 phase: An increasing body of evidence has shown that many cancer cells develop an addiction to the nuclear transport machinery and have increased numbers of Nuclear Pore Complexes (NPCs), the multi- protein structures that regulate the nucleocytoplasmic transport of molecules. Recent work has revealed that inhibition of the assembly of NPCs could represent an effective target for cancer therapeutics. However, the molecular factors that regulate NPC assembly are incompletely understood and a targetable pathway has yet to be identified. A whole genome siRNA screen was performed to find genes that regulate assembly of these structures. Genes were identified that, when knocked down, either increase or decrease the NPC content on the surface of the nucleus. Knockdown of 3 members of the CCR4-NOT complex were found to increase NPCs. The CCR4-NOT is a major deadenylase complex that controls protein levels via regulation of mRNA metabolism in eukaryotes. The work proposed here will characterize the effect of CNOT knockdown on the NPC number/functionality and how these changes alter basic cellular physiology. Additionally, this work will elucidate the molecular mechanism by which the CCR4-NOT complex regulates NPCs. The K00 phase: In recent years immuno-oncology therapies, namely immune checkpoint blockers, have shown remarkable clinical efficacy however only a small proportion of patients respond to treatments. One of the reasons underlying the lack of efficacy stems from the presence of a strong immunosuppressive tumor microenvironment (TME). Until the TME can be modified into a more immuno-activating environment, immune checkpoint blockade therapies will have limited success. The K00 phase of this project will focus on a unique and dynamic leukocyte that strongly contributes to the observed immunosuppression; the Tumor-Associated Macrophage (TAM). TAMs have been shown to compose up to 50% of a tumor’s mass and have both pro- and anti-tumorigenic phenotypes. The need remains to develop more effective strategies to target this cell type and reprogram it. The K00 research will characterize the transcriptional networks that can be harnessed to modulate macrophage repolarization in the TME. Successful completion of the F99 phase will reveal a targetable cell-intrinsic aspect of cancer biology, while completion of the K00 phase will reveal an immuno-oncology targetable pathway.