A Stem Cell Based Exosomal Vaccine for the Prevention of Cancer

项目总结/摘要 肺癌是一种常见病，每年都要夺去许多人的生命.疾病复发、侵袭和 转移是死亡的主要原因。最近的发现提供了令人信服的证据，至少有一些 一种类型的癌症是由一小群称为癌症起始细胞的恶性细胞引发和维持的。 干细胞（CIC）。复发、侵袭和转移可以通过CIC具有不同的免疫学特性来解释。 它比其他所有肿瘤细胞都具有更高的生物学特性，而且重要的是，它对化疗和放射具有抵抗力。肺 CIC已被证明代表所有肿瘤细胞的约1-15%，并且可以在低剂量注射时形成肿瘤。 一百个细胞已发表的研究证据表明，人类和啮齿动物的癌症 含有表达胚胎干（ES）细胞抗原的细胞群。含有这些蛋白质的细胞 也表达用于识别肺CIC的标记物;因此，我们假设ES细胞和CIC共享 几种常见的分子特征为了验证这一假设，我们用来自ES的外泌体接种小鼠， 表达GM-CSF的细胞，并研究是否引发了抗肿瘤免疫应答。我们 发现ES细胞衍生的基于外泌体的疫苗接种策略（ES-exo疫苗）在 预防植入性肺腺癌和致癌物诱导的肺腺癌的发展，而无需任何 可检测的毒性或自身免疫的迹象。我们实验室最近发表的结果显示， 来自ES细胞免疫小鼠的脾细胞优先对肺CIC具有细胞毒性。建议的实验 本申请试图扩展这些新发现，以令人信服地证明ES-exo疫苗 免疫对抗肺癌相关CIC，且抗CIC免疫负责预防肺 腺癌发展。ES-exo疫苗的抗肿瘤活性及其免疫刺激作用 将在体外和体内肺癌小鼠模型中研究这些性质。在此提出的实验 这项研究将探讨我们的新型ES-exo疫苗作为无细胞预防性疫苗的翻译潜力 在可植入的、转基因的和异种移植的肺癌小鼠模型中的模式。其中一个主要目标是 本申请的目的是使用免疫组织化学方法鉴定对ES-exo疫苗的抗肺癌功效重要的肿瘤抗原。 基于蛋白质组学的筛选方法。为了实现上述目标，提出了以下目标：1） 研究肺癌起始细胞是否是ES细胞衍生的外泌体（ES-exo）疫苗接种的靶点- 诱导的抗肿瘤免疫，和2）评估ES细胞来源的外泌体（ES-exo）的翻译潜力 作为一种新型的肺癌无细胞疫苗。我们提出的研究将提供重要的见解， 开发用于肺癌发作和/或复发的安全预防性疫苗。

PROJECT SUMMARY/ABSTRACT Lung cancer is a prevalent disease and consume many lives every year. Disease relapse, invasion and metastases are the main causes of death. Recent discoveries provide compelling evidence that at least some types of cancer are initiated and maintained by a small population of malignant cells called cancer-initiating stem cells (CICs). Relapse, invasion, and metastases are explained by the fact that CICs have a different biology than all the other tumor cells and, importantly, are resistant to chemotherapies and radiation. Lung CICs have been shown to represent about 1–15% of all tumor cells and can form tumors with injections as low as 100 cells. Evidence from published studies have demonstrated that human, as well as rodent, cancers contain populations of cells that express embryonic stem (ES) cell antigens. Cells containing these proteins also express markers used to identify lung CICs; therefore, we hypothesized that ES cells and CICs share several common molecular traits. To test this hypothesis, we vaccinated mice with exosomes derived from ES cells expressing GM-CSF and investigated whether an anti-tumor immune response was elicited. We discovered that ES cell-derived exosome-based vaccination strategy (ES-exo vaccine) is very effective in preventing both implantable and carcinogen-induced lung adenocarcinoma development without any detectable toxicity or signs of autoimmunity. Recently published results from our laboratory reveal that splenocytes from ES cell-immunized mice are preferentially cytotoxic to lung CICs. Experiments proposed in this application seek to expand these novel findings to convincingly demonstrate that ES-exo vaccine immunize against lung cancer-associated CICs and that anti-CIC immunity is responsible for preventing lung adenocarcinoma development. The anti-tumor activities of ES-exo vaccine as well as their immunostimulatory properties will be investigated in in vitro and in vivo lung cancer mouse models. Experiments proposed in this study will address the translational potential of our novel ES-exo vaccine as a cell-free prophylactic vaccine modality in implantable, transgenic and xenograft mouse models of lung cancer. One of the major goals of this application is to identify tumor antigens important for anti-lung cancer efficacy of ES-exo vaccine using a proteomics-based screening methodology. To fulfill the stated objectives, the following aims are proposed: 1) Investigate whether lung cancer-initiating cells are targets of ES cell-derived exosomes (ES-exo) vaccination- induced anti-tumor immunity, and 2) Evaluate the translational potential of ES cell-derived exosomes (ES-exo) as a novel cell-free vaccine for lung cancer. Our proposed study will provide important insights towards developing a safe prophylactic vaccine for lung cancer onset and/or recurrence.