The role and regulation of Hippo pathway in sarcomagenesis

Hippo通路在肉瘤发生中的作用及调控

• 批准号: 10337813
• 负责人: Tzipora Sarah Karin Eisinger
• 金额: $ 5.74万
• 依托单位: UNIVERSITY OF PENNSYLVANIA
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-08-01 至 2024-02-29
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10337813
• 关键词: AMOT gene; Adult; Binding; Carcinoma; Cell Proliferation; Cells; ChIP-seq; Data; Diagnosis; Gene Chips; Gene Expression; Genetic Transcription; Goals; Growth; Human; In Vitro; Lysine; Malignant Fibrous Histiocytoma; Malignant Neoplasms; Mediating; Mediator of activation protein; Mesenchymal; Mesenchymal Cell Neoplasm; Modification; Mus; Muscle; Myomatous neoplasm; Pathway interactions; Patients; Peptide Hydrolases; Process; Promoter Regions; Protein Isoforms; Regulation; Role; Sampling; Signal Transduction; Skeletal Muscle; Soft tissue sarcoma; Testing; Ubiquitin; Work; base; cancer cell; clinically actionable; mouse model; new therapeutic target; p65; prevent; progenitor; sarcoma; targeted treatment; therapeutic target; tumor; tumor initiation; tumorigenesis

Project Summary/Abstract Soft tissue sarcomas are an aggressive group of mesenchymal malignancies diagnosed in 200,000 people per year worldwide. Unlike in epithelial cancers, where novel targeted therapies have had a dramatic effect on patient survival, the treatment approach for mesenchymal tumors including sarcomas has not changed significantly in 25 years. Our recent work revealed that deregulation of the Hippo pathway enhances sarcomagenesis in the aggressive muscle tumor, Undifferentiated pleomorphic sarcoma (UPS). UPS is a commonly diagnosed and metastatic sarcoma subtype frequently found in adult muscle tissues. We have observed that loss of Angiomotin (AMOT), a crucial mediator of Hippo-associated growth restriction, is required for UPS sarcomagenesis. AMOT is highly expressed in differentiated human muscle tissue but is silenced in UPS and other sarcomas. Ectopic re-expression of the p130 isoform of AMOT significantly inhibits sarcoma cell proliferation in vitro. This finding is consistent with the only known function of AMOT in cancer cells, which is to sequester the Hippo pathway effector YAP1 and facilitate its degradation. YAP1 is a pro-proliferation transcriptional regulator whose deletion in an autochthonous mouse model of UPS significantly decreased tumorigenesis. Together these data suggest that AMOT loss promotes YAP-mediated sarcomagenesis in muscle-derived UPS. We next investigated the downstream effects of YAP1 expression in UPS by microarray gene expression studies of control and Yap1-deficient murine tumors. We found that Yap1 controls NF-κB signaling in UPS by suppressing expression of Usp31, a negative regulator of NF-κB activity. Furthermore, using ChIP-seq of patient samples we found that NF-κB signaling is substantially upregulated in human UPS. Consistent with these findings, UPS cell proliferation is highly sensitive to NF-κB inhibition. Based on these findings in Specific Aim1 we will determine how AMOT loss is controlled in UPS and if this process is required for tumor initiation in soft tissue sarcomas. Next we will define the mechanism by which YAP1 suppresses USP31 expression in Specific Aim 2. We will investigate whether YAP1 directly binds to the promoter region of USP31, preventing its transcription. Loss of YAP1 restores expression of USP31, a peptidase that removes activation specific ubiquitin modifications from lysine 63 in TRAF molecules upstream of p65, thereby inactivating NF-κB. The role of NF-κB in normal skeletal muscle progenitors, the putative cell of origin of UPS, is to promote proliferation and prevent differentiation. In Specific Aim3 we will determine which YAP1- dependent NF-κB targets are necessary for regulating either or both of these processes. The goal of this proposal is to test the hypothesis that deregulated Hippo signaling promotes sarcomagenesis via suppression of AMOT, resulting in YAP1/NF-κB-associated proliferation and inhibition of differentiation. Ultimately, the purpose of these studies is to identify clinically actionable therapeutic targets to advance treatment for skeletal muscle UPS patients.

项目摘要/摘要 软组织肉瘤是一种侵袭性的间叶性恶性肿瘤，在20万人中被诊断出来 全球每年的人流量。与上皮癌不同，在上皮癌中，新的靶向治疗已经有了戏剧性的 对患者生存的影响，包括肉瘤在内的间叶性肿瘤的治疗方法尚未 在25年里发生了巨大的变化。我们最近的工作表明，放松河马途径的监管可以增强 肉瘤发生于侵袭性肌肉瘤、未分化多形性肉瘤(UPS)。UPS是一种 常见诊断和转移性肉瘤亚型，常见于成人肌肉组织。我们有 观察到，河马相关生长限制的关键介质血管蛋白(Amot)的丢失是必需的。 用于UPS肉瘤发生。AMOT在分化的人类肌肉组织中高度表达，但在 UPS和其他肉瘤。异位再表达p130亚型的AMOT显著抑制肉瘤生长 细胞在体外增殖。这一发现与AMOT在癌细胞中唯一已知的功能一致，即 是隔离河马途径效应器YAP1并促进其降解。YAP1是一个支持核扩散的 转录调控因子在UPS模型小鼠模型中的缺失显著减少 肿瘤发生学。综上所述，这些数据表明，AMOT丢失促进了YAP介导的肿瘤发生 肌肉来源的UPS。接下来，我们利用基因芯片研究了YAP1在UPS中的表达对下游的影响 对照和YAP1缺陷小鼠肿瘤的基因表达研究。我们发现YAP1控制着NF-κB 通过抑制NF-κB活性的负性调节因子USP31的表达在不稳定蛋白中的信号转导。此外， 使用患者样本的芯片序列，我们发现NF-κB信号在人类UPS中显著上调。 与这些发现一致的是，UPS细胞的增殖对核因子-κB的抑制高度敏感。基于这些 在特定目标中的发现1我们将确定UPS中的多项损失如何控制，以及是否需要此过程 用于软组织肉瘤的肿瘤起始。接下来，我们将定义YAP1抑制的机制 USP31在特定目的的表达2.我们将研究YAP1是否直接与启动子区域结合 USP31，阻止其转录。YAP1的缺失恢复了USP31的表达，USP31是一种去除 激活p65上游TRAF分子中赖氨酸63的特异性泛素修饰，从而 失活核因子-κB在正常骨骼肌祖细胞中的作用，正常骨骼肌祖细胞是UPS的可能起源细胞， 就是促进增殖和防止分化。在具体的Aim3中，我们将确定哪个YAP1- 依赖的NF-κB靶标对于调节这两个过程中的一个或两个是必需的。这样做的目的是 一项提议是检验放松河马信号通过抑制促进肉瘤形成的假设 导致YAP1/NF-κB相关的增殖和分化抑制。归根结底， 这些研究的目的是确定临床上可操作的治疗靶点，以促进骨骼疾病的治疗 肌肉发达的UPS患者。