Dissecting the interplay between deregulated signaling networks and aberrant YAP/TAZ activity in myxoid liposarcoma

剖析粘液样脂肪肉瘤中信号网络失调与异常 YAP/TAZ 活性之间的相互作用

• 批准号: 455323733
• 负责人: Professor Dr. Stefan Fröhling
• 金额: --
• 依托单位: Gerhard-Domagk-Institut für Pathologie
• 依托单位国家: 德国
• 项目类别: Research Grants
• 资助国家: 德国
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/455323733?language=en
• 关键词: Dissecting; interplay; between; deregulated; signaling

Dissecting the interplay between deregulated signaling networks and aberrant YAP/TAZ activity in myxoid liposarcomaMyxoid liposarcoma (MLS) are malignant adipocytic tumors driven by the FUS-DDIT3 fusion gene encoding an aberrant transcription factor. The mechanisms whereby FUS-DDIT3 mediates sarcomagenesis are incompletely understood, and strategies to selectively target MLS cells remain elusive. We have previously shown that MLS cells are dependent on YAP, the central effector of the Hippo pathway, that FUS-DDIT3 promotes YAP expression and transcriptional activity, and that both proteins physically interact. Furthermore, we provided evidence of recurrent PI3K/AKT signaling pathway activation in MLS through mutations in PIK3CA, PTEN loss, or FUS-DDIT3-dependent transcriptional induction of a cell-autonomous IGF-II/IGF-IR feed-forward mechanism. Recent data from others documented physical interactions between the Hippo effectors YAP/TAZ and members of the epigenetic regulatory SWI/SNF complex, which modulate the formation YAP/TAZ-TEAD complexes. In addition, the FUS-DDIT3 protein itself was shown to associate with SWI/SNF subunits. The functional interplay between FUS-DDIT3, activated kinase signaling, the Hippo-YAP/TAZ cascade, and the SWI/SNF complex has not been investigated in MLS.The first part of the project will include immunohistochemical investigations and analyses of whole-exome/genome and RNA sequencing data in a large cohort of MLS tissues to identify informative patterns of YAP/TAZ, PI3K/AKT, and MEK/ERK activation.The second part will address regulatory dependencies between FUS-DDIT3, specific kinase pathways, and YAP/TAZ activation in vitro through (i) interrogation of kinase pathways known to be of relevance in MLS and (ii) an unbiased CRISPR interference screen to identify signaling intermediates specifically acting between kinases and phosphatases and the Hippo pathway.The third part will be dedicated to elucidating physical associations between FUS-DDIT3, YAP/TAZ, TEAD, and selected SWI/SNF complex proteins by systematic co-immunoprecipitation experiments, focusing on interactions that modulate YAP/TAZ signals in MLS.Employing a combined antibody-guided chromatin tagmentation sequencing and RNA sequencing approach, the fourth part will approach the transcriptional interplay between YAP/TAZ, FUS-DDIT3, and the SWI/SNF complex through identification of genomic loci/chromatin sites regulated in a specific/overlapping manner. Against this background, it will comparatively analyze the distribution of functional chromatin marks and gene expression profiles upon modulation of YAP/TAZ, FUS-DDIT3, and selected SWI/SNF complex members.The results of this project will contribute to the understanding of MLS biology and will lay the groundwork for the development of future molecularly targeted therapies.

剖析粘液样脂肪肉瘤中信号网络失调与异常 YAP/TAZ 活性之间的相互作用粘液样脂肪肉瘤 (MLS) 是由编码异常转录因子的 FUS-DDIT3 融合基因驱动的恶性脂肪细胞肿瘤。 FUS-DDIT3 介导肉瘤发生的机制尚不完全清楚，选择性靶向 MLS 细胞的策略仍然难以捉摸。我们之前已经证明，MLS 细胞依赖于 Hippo 通路的中心效应子 YAP，FUS-DDIT3 促进 YAP 表达和转录活性，并且两种蛋白质发生物理相互作用。此外，我们提供了 MLS 中 PI3K/AKT 信号通路通过 PIK3CA 突变、PTEN 缺失或细胞自主 IGF-II/IGF-IR 前馈机制的 FUS-DDIT3 依赖性转录诱导反复激活的证据。来自其他人的最新数据记录了 Hippo 效应器 YAP/TAZ 与表观遗传调节 SWI/SNF 复合体成员之间的物理相互作用，该复合体调节 YAP/TAZ-TEAD 复合体的形成。此外，FUS-DDIT3 蛋白本身也被证明与 SWI/SNF 亚基相关。 FUS-DDIT3、激活的激酶信号传导、Hippo-YAP/TAZ 级联和 SWI/SNF 复合物之间的功能相互作用尚未在 MLS 中进行研究。该项目的第一部分将包括全外显子组/外显子组的免疫组织化学研究和分析。大量 MLS 组织中的基因组和 RNA 测序数据，以识别 YAP/TAZ、PI3K/AKT 和 MEK/ERK 激活的信息模式。第二部分将解决之间的监管依赖性FUS-DDIT3、特定激酶途径和 YAP/TAZ 体外激活，通过 (i) 询问已知与 MLS 相关的激酶途径，以及 (ii) 无偏见的 CRISPR 干扰筛选来识别在激酶和磷酸酶之间特异性作用的信号传导中间体，第三部分将致力于通过系统地阐明 FUS-DDIT3、YAP/TAZ、TEAD 和选定的 SWI/SNF 复合蛋白之间的物理关联免疫共沉淀实验，重点关注 MLS 中调节 YAP/TAZ 信号的相互作用。第四部分将采用抗体引导的染色质标记测序和 RNA 测序相结合的方法，探讨 YAP/TAZ、FUS-DDIT3 和SWI/SNF 复合物通过识别以特定/重叠方式调节的基因组位点/染色质位点。在此背景下，将比较分析YAP/TAZ、FUS-DDIT3和选定的SWI/SNF复合体成员调节后功能染色质标记的分布和基因表达谱。该项目的结果将有助于理解MLS生物学并将为未来分子靶向治疗的发展奠定基础。