Proteomic and lipidomic profiling of tumor-derived exosomes for cancer prevention

描述(由申请人提供)： 早期和频繁的结直肠癌筛查将能够在仍可治疗的情况下发现局部的早期肿瘤，从而显著降低与这种疾病相关的严重死亡率。为了实现这一目标，我们建议采取一种新的方法，将结直肠癌来源的外切体的脂肪组学和蛋白质组学分析结合起来，努力通过提高我们对结直肠癌生物学和细胞-细胞通讯的理解，并通过定义可用作筛查、分期和跟踪患者治疗的组织特异性标记物的目录来努力预防结肠癌。外切体是一种独特的囊泡，由细胞分泌，并从起始点运输到远离起始点，与其局部环境相互作用，或通过血液在体内运输。它们独特的蛋白质组学特征是肿瘤细胞特有的，因此为确定组织起源和状态提供了机会。这些信息可用于改进晚期结直肠癌预防的诊断策略，并进一步了解结直肠癌生物学。首先，我们将为正常结肠上皮和结直肠癌来源的外切体定义一个纯化方案。我们将使用新开发的脂体学方法来定量确定定义肿瘤特异性外切体的脂谱。结合脂肪分析和蛋白质组分析，以及组织特异性蛋白质的覆盖，将提供一组标记，以唯一地识别存在于许多体液中的组织特异性肿瘤来源的外切体。这种将外体定量脂谱与蛋白质谱相结合的独特方法将最终促进我们对外体在结直肠癌生物学中的功能的理解，并使识别高度信息量和临床有用的生物标志物成为可能。

DESCRIPTION (provided by applicant): Early and frequent screening for colorectal cancer will enable detection of localized early-stage tumors while they are still treatable, thus significantly reducing the drastic mortality rate associated with this disease. To achieve this, we propose to take the novel approach of combining lipidomic and proteomic analysis of colorectal cancer-derived exosomes in an effort to prevent colon cancer by improving our understanding of colorectal cancer biology and cell-cell communication and by defining a catalogue of tissue-specific markers that can be used as tools to screen, stage, and follow the treatment of patients. Exosomes are unique encapsulated vesicles that are secreted from cells and transported away from the originating site to interact with their localized environment or transported around the body through blood. Their unique proteomic profiles are specific to the tumor cell and thus provide an opportunity to define tissue origin and status. This information can be used to improve diagnostic strategies for the prevention of late stage colorectal cancer and to gain further insight into colorectal cancer biology. First, we will define a purification protocol for normal colon epithelial and colorectal cancer-derived exosomes. We will use newly developed lipidomic approaches to quantitatively determine the lipid profile that defines tumor-specific exosomes. The combination of lipidomic analysis and proteomic analysis, with an overlay of tissue-specific proteins will provide a set of markers that will uniquely identify tissue-specific tumor-derived exosomes that are present in many body fluids. This unique approach of integrating quantitative exosomal lipid profiles with protein profiles will ultimately advance our understanding of exosome function in colorectal cancer biology and enable the identification of highly informative and clinically useful biomarkers.