Regulation of extracellular vesicle biogenesis through cell adhesion

摘要 转移是众所周知的癌症相关死亡的驱动因素。尽管如此，在以下方面取得的成功有限 以癌症转移为目标，因为这是一个极其复杂的过程，由多个、集成的 机械装置。Zijlstra和Weaver实验室的合作研究研究了细胞的两个不同方面 运动性：a)由黏附受体的蛋白水解性脱落控制的细胞间黏附的动力学和b) 释放促进运动的胞外小泡(EV)。由于这两个事件发生在相同的牢房中， 导致相同的表型，我们推测这两个生物学过程是协调的。的确， 初步研究表明，肠病毒生物发生途径的关键成分Syntenin-1是 由Ig G超家族成员激活的白细胞黏附分子锚定的细胞黏附复合体 (Alcam)及其伴侣--Tetraspanin CD151。极大地改变alcam的表达和/或脱落 影响EV的生物发生，证实了我们最初的想法，即细胞间的黏附可以与EV协调 生物发生学。假设这是通过alcam和syntenin之间的细胞内联系发生的 进一步支持细胞内游离结构域抑制EV生物发生的能力。基于这些 以及我们在细胞黏附、EV生物学和转移方面的已发表的专业知识，我们建议研究 在癌症进展过程中细胞黏附和促进运动的EVS的产生之间的整合。 具体地说，拟议的研究将调查：1)细胞黏附和电动汽车之间的机械整合 生物发生，2)货物并入促进运动的电动汽车的后果，以及3)功能 对自分泌和旁分泌交流的贡献。此外，这种生物学的相关性将在 膀胱癌的背景下，Alcam脱落是一个独立的预后指标。为 为此，我们开发了一种新型的膀胱尿路上皮和膀胱的体外器官型培养系统。 我们可以复制乳头状瘤和膀胱癌的临床表型的癌症。 考虑到肿瘤细胞具有大量的分化机制，它们可以通过这些机制 增强其恶性行为，确定细胞黏附和EV生物发生机制如何整合 不仅是一种解卷复杂转移行为的创新方法，它还将具有重大的临床意义 冲击力。根据拟议研究的结果，将提供新的干预途径，其中治疗方法可能 以协同和整合为目标，而不是直接的行动模式。

Abstract Metastasis is a well-known driver of cancer-related deaths. Nevertheless, limited success has been achieved in targeting cancer metastasis because it is an exceedingly complex process driven by multiple, integrated mechanisms. Collaborative studies in the Zijlstra and Weaver laboratories studied two separate aspects of cell motility: a) the dynamics of cell-cell adhesion controlled by proteolytic shedding of adhesion receptor and b) the release of motility promoting extracellular vesicles (EV). Since these two events take place in the same cells and contributed to the same phenotype, we speculated that these two biological processes were coordinated. Indeed, preliminary studies demonstrated that syntenin-1, a key component of the EV biogenesis pathways, was part of a cell adhesion complex anchored by the IgG superfamily member Activated Leukocyte Cell Adhesion Molecule (ALCAM) and its companion-tetraspanin CD151. Altering the expression and/or shedding of ALCAM drastically impacted EV biogenesis, confirming our original idea that cell-cell adhesion could be coordinated with EV biogenesis. The hypothesis that this occurred through an intracellular link between ALCAM and syntenin is further supported by the ability of free intracellular domain to suppress EV biogenesis. Based on these observations and our published expertise in cell adhesion, EV biology and metastasis, we propose to investigate the integration between cell-adhesion and the production of motility-promoting EVs during cancer progression. Specifically, the proposed studies will investigate: 1) the mechanistic integration between cell-adhesion and EV biogenesis, 2) the consequences for cargo incorporated in motility-promoting EVs, and 3) the functional contribution to autocrine and paracrine communication. Moreover, the relevance of this biology will be tested in the context of bladder cancer where ALCAM shedding is an independent prognostic indicator of survival. For this purpose we have developed a novel ex vivo organotypic culture system for bladder urothelium and bladder cancer in which we can replicate the clinical phenotypes of both papilloma and carcinoma of the bladder. Considering that tumor cells have a large number of divergent mechanisms at their disposal by which they can enhance their malignant behavior, determining how mechanisms of cell adhesion and EV biogenesis integrate is not only an innovative way to deconvolve complex metastatic behavior, it will also have significant clinical impact. With findings from the propose studies, will provide novel avenues of intervention where a therapy may target a point of synergy and integration rather than a direct mode of action.