Isolation and Assessment of Blood-Circulating Cancer Exosomes with LSS and SERS Lab on a Chip Optical Spectroscopic Instrument

项目摘要 从原发性肿瘤脱落到外周循环中，循环肿瘤细胞（CTC）受到以下限制： 它们在血液中的浓度极其稀少。相反，肿瘤细胞分泌的分子标记物 进入血管系统的浓度要高得多，可以提供重要的见解， 癌细胞生物学和用于早期检测、进展和转移的预测性生物标志物。这些 标记物，包括可溶性蛋白质、无细胞DNA（cfDNA）和循环微泡和外来体 已经显示包含关于通常难以接近的肿瘤的分子状态的有价值的信息 网站.不幸的是，血液中发现的可溶性蛋白质的来源无法确定，导致 高的假阳性率，而显著更特异的cfDNA通常反映了死亡或凋亡。 细胞外泌体是一种内吞来源的小膜囊泡， 由于其独特的性质，可用于早期癌症检测和监测的生物标志物，包括 它们在生物流体中的稳定性和它们被有效分离的潜力。癌细胞释放更多的 外泌体比正常细胞和肿瘤细胞分泌的外泌体能促进肿瘤进展， 存活、侵袭和血管生成。 在本申请中，我们提出开发一种光学光谱技术，其结合了 光散射光谱（LSS）和表面增强拉曼光谱（Sers）， 严格分离和评估血液循环癌症外泌体用于早期癌症检测， 快速和廉价的芯片实验室系统。如本申请所示，不仅LSS可以分离 外泌体从微泡，目前还没有能力，但它也可以区分 各种类型的外泌体起源于消化道的不同器官，而Sers能够 区分由同一器官的癌细胞和正常细胞分泌的外泌体。

Project Summary Shed into the peripheral circulation from a primary tumor, circulating tumor cells (CTCs) are limited by their extremely sparse concentrations in blood. In contrast, molecular markers secreted by tumor cells into the vasculature are present in much higher concentrations and could provide important insight on cancer cell biology and predictive biomarkers for early detection, progression and metastasis. These markers, including soluble proteins, cell-free DNA (cfDNA), and circulating microvesicles and exosomes have been shown to contain valuable information on the molecular state of often difficult to access tumor sites. Unfortunately, the source of the soluble proteins found in blood cannot be determined, resulting in the high false-positive rates, while significantly more specific cfDNA often reflect the dying or apoptotic cells. Exosomes, small membrane vesicles of endocytic origin, show the greatest potential as an easily accessible biomarker for early cancer detection and monitoring due to their unique properties, including their stability in biological fluids and their potential to be efficiently isolated. Cancer cells release more exosomes than normal cells and exosomes secreted from tumor cells can promote tumor progression, survival, invasion and angiogenesis. In this application we propose to develop an optical spectroscopic technique, which combines light scattering spectroscopy (LSS) and surface enhanced Raman spectroscopy (SERS) for highly rigorous isolation and assessment of blood-circulating cancer exosomes for early cancer detection in a rapid and inexpensive lab-on-a-chip system. As it is shown in this application, not only LSS can separate exosomes from microvesicles, the capability not available at the moment, but it also can differentiate various types of exosomes originated in different organs of the digestive tract, while SERS is capable of differentiating exosomes secreted by cancerous and normal cells of the same organ.