Molecular Mechanisms of Large Oncosome-Induced Prostate Cancer Progression and Metastasis

摘要 前列腺癌(PC)是男性最常见的肿瘤之一。尽管最近取得了进展，但这种疾病仍然无法治愈 一旦对去势治疗产生抵抗。肿瘤进展受到分子变化的强烈影响 癌细胞与周围环境之间的交换，起源于原发部位。然而， 调节间质对肿瘤的反应，最终促进PC进展的机制是 这在很大程度上仍然是未知的。我们实验室发现了一种新型的肿瘤来源的细胞外小泡，它是 被称为“大的内涵体”(LO)，可以容纳更丰富的分子货物，是不同的和更有效力的 比外切体携带的更具生物活性。这项建议的理由来自我们在#年的初步观察 循环中LO丰度与PC进展相关的患者。我们的功能数据表明 LO可以激活成纤维细胞中的致癌信号，成纤维细胞通过激活MYC和SPI1以及通过 诱导一个促进血管生成和刺激肿瘤生长的转录程序。的首要目标是 本研究旨在探讨LO在前列腺癌进展和转移中的作用。我们假设Lo 功能性地将正常前列腺相关成纤维细胞(NAF)重新编程为由MYC和MYC驱动的表型 SPI1激活。这些结果强烈表明，肿瘤来源的LO可能激活细胞间反应，这些反应是 细胞外小泡的这一亚型。我们的假设将通过三个具体目标进行检验：目标1： 探讨LO诱导的成纤维细胞活化在PC进展中的作用。目标2：找到证据证明Lo- 在有临床意义疾病的PC患者中，诱导转录程序是活跃的。目标3：测试日志是否 和/或来源于PC患者和PDX标本的Exo可促进去势抵抗和/或骨转移。 我们将使用互补的体外和动物原位模型的组合以及聚焦 方法包括基因组编辑、分子条形码和活体系统中的Cre-Lox报告程序。我们的研究将 确定LO在体外诱导的转录程序是否在体内驱动肿瘤的进展和转移。 此外，我们将确定这种转录程序是否也可以在患者样本中识别，以及它是否 预示着肿瘤的进展。最后，我们的研究将为LO诱导肿瘤转移的能力提供证据。 懒惰的PC细胞。

Abstract Prostate cancer (PC) is one of the most frequent tumors in men. Despite recent progress, the disease is still incurable once resistance to castration therapy occurs. Tumor progression is strongly mediated by altered molecular exchanges between cancer cells and the surrounding milieu that originate at the primary sites. However, the mechanisms regulating the response of the stroma to the tumor, which ultimately promote PC progression are still largely unknown. Our laboratory discovered a new type of tumor-derived extracellular vesicle (EV), which are referred to as “large oncosomes” (LO), can harbor more abundant molecular cargo that is distinct and more potently bioactive than that carried by exosomes. The rationale for this proposal derives from our preliminary observations in patients that LO abundance in the circulation correlates with PC progression. Our functional data demonstrate that LO can activate oncogenic signaling in fibroblasts, which respond to LO uptake by activating MYC and SPI1 and by induce a transcriptional program that promotes angiogenesis and stimulates tumor growth. The overarching goal of this project is to determine the functional role of LO in PC progression and metastasis. We hypothesize that LO functionally reprogram normal prostate-associated fibroblasts (NAF) toward a phenotype that is driven by MYC and SPI1 activation. These results strongly suggest that tumor-derived LO might activate intercellular responses that are specific to this subtype of extracellular vesicle. Our hypothesis will be tested with three Specific Aims: Aim 1: To investigate the role of LO-induced fibroblast activation in PC progression. Aim 2: To find evidence that the LO- induced transcriptional program is active in PC patients with clinically significant disease. Aim 3: To test if LO and/or Exo derived from PC patient and PDX specimens promote castration resistance and/or bone metastasis. We will use a combination of complementary in vitro and animal orthotopic models as well as focused approaches involving genome editing, molecular barcodes, and a Cre-Lox reporter in vivo system. Our study will determine if the transcriptional program induced by LO in vitro drives tumor progression and metastasis in vivo. Additionally we will determine if this transcriptional program can also be identified in patient specimens and if it indicative of tumor progression. Finally, our study will provide evidence for LO abilities to induce metastasis of indolent PC cells.