Exosomes in tumor cell-mesenchymal stromal cell interaction

摘要 骨髓（BM）是在癌症进展和转移中具有中心功能的异质器官。 它为播散的肿瘤细胞构成了一个小生境，保护它们免受治疗，促进它们的休眠， 从而转移到其他器官癌细胞回家并劫持BM利基，将其转化为 恶性小生境有利于肿瘤细胞增殖和存活。因此，研究肿瘤之间的串扰 细胞和BM微环境是高度感兴趣的主题。我们实验室的一项主要工作是 研究癌细胞和骨髓间充质干细胞（BM-MSC）之间的通讯， 形成BM-小生境，并且我们已经证明有助于促肿瘤发生的肿瘤微环境（TME）。 我们关注神经母细胞瘤（NB），这是一种神经嵴来源的肿瘤，是第二常见的实体瘤， 儿童，并且经常和特异性地转移到骨和BM以及肿瘤外泌体上。 这些细胞外囊泡（EV）已经成为一种新的和强大的通信机制， 肿瘤细胞及其环境通过其传递多分子生物学信息的能力， 比单一的生长因子更复杂。本申请的初步数据表明，NB细胞 释放富含syntenin、阿利克斯、四跨膜蛋白CD-63和Gal-3BP的外泌体，其被BM-10捕获。 MSC和促肿瘤性炎症反应。我们的总体假设是，由于他们的 在MSC上的活性，NB衍生的外泌体启动BM生态位，促进NB的归巢和存活 BM中的细胞。我们特别假设syntenin在它们的生物发生中起着核心作用， Gal-3BP通过与BM-MSC表面的蛋白质相互作用来控制它们的摄取。在第一个目标中， 我们将确定NB衍生的外泌体对转移前BM小生境的贡献，以及NB衍生的外泌体对转移前BM小生境的贡献。 结合药理学和遗传学（敲除和敲除） 体外培养患者来源的MSC和体内转移性和非转移性NB细胞的方法 线在目标2中，我们将在BM-MSC中鉴定与Gal-3BP相互作用的蛋白质，所述蛋白质有助于在BM-MSC中表达Gal-3BP。 在MSC中摄取外泌体，并与大卫莱登博士（康奈尔大学，纽约）合作，比较 来自NB和乳腺癌细胞系的外泌体，其被BM-MSC和BM摄取的BM向性不同 造血干细胞（HSC）在其摄取中集中于Gal-3BP和整联蛋白。这些研究将提供 对外来体参与肿瘤细胞之间通讯的机制的新见解， BM niche。预计这些研究将最终确定干预或预防的目标， 癌症转移

ABSTRACT The bone marrow (BM) is a heterogeneous organ with a central function in cancer progression and metastasis. It constitutes a niche for disseminated tumor cells, protecting them from therapy, promoting their dormancy and allowing them to metastasize to other organs. Cancer cells home to and hijack the BM niche converting it to a malignant niche favorable to tumor cell proliferation and survival. Thus, studying the cross-talk between tumor cells and the BM microenvironment is a subject of high interest. A major effort of our laboratory has been to study the communication between cancer cells and BM-derived mesenchymal stromal cells (BM-MSC) that form the BM-niche and that we have shown to contribute to a protumorigenic tumor microenvironment (TME). We focus on neuroblastoma (NB), a neural crest-derived tumor that is the second most common solid tumor in children, and that frequently and specifically metastasizes to the bone and BM and on tumor exosomes. These extracellular vesicles (EV) have emerged as a new and powerful mechanism of communication between tumor cells and their environment through their ability to convey multi-molecular biological messages of a much higher complexity than single growth factors. Preliminary data in this application demonstrate that NB cells release exosomes enriched in syntenin, ALIX, the tetraspanin CD-63 and Gal-3BP which are captured by BM- MSC and a pros-tumorigenic inflammatory reaction. Our overarching hypothesis is that as a result of their activity on MSC, NB-derived exosomes prime the BM niche, promoting the homing and survival of NB cells in the BM. We specifically hypothesize that syntenin plays a central role in their biogenesis and that Gal-3BP controls their uptake by interacting with a protein at the surface of BM-MSC. In a first aim we will determine the contribution of NB-derived exosomes to the pre-metastatic BM niche and the contribution of syntenin to their biogenesis, combining pharmacological and genetic (knock down and knock out) approaches in vitro in cultures of patient-derived MSC and in vivo in metastatic and non-metastatic NB cell lines. In aim 2, we will identify in BM-MSC the protein(s) interacting with Gal-3BP that contribute(s) to the uptake of exosomes in MSC, and in collaboration with Dr. David Lyden (Cornell University, NY), compare exosomes from NB and breast cancer cell lines that differ in BM tropism for their uptake by BM-MSC and BM hematopoietic stem cells (HSC) focusing on Gal-3BP and integrin in their uptake. These studies will provide novel insight into mechanisms by which exosomes are involved in the communication between tumor cells and the BM niche. It is anticipated that these studies will ultimately identify targets for intervention or prevention of cancer metastasis.