Shaping the Microenvironment by DPEP1 Facilitates Adenoma Progression

项目概要/摘要 项目1：通过DPEP 1塑造微环境促进腺瘤进展 项目1旨在研究DPEP 1如何塑造微环境促进腺瘤进展。这 这将是一个基本的项目。我们认为，二肽酶-1（DPEP 1）标志着这些腺瘤的潜力， 通过与嗜中性粒细胞的主动双向通信进展为结直肠癌（CRC）。DPEP1 具有两种功能：二肽酶活性和最近鉴定的亲脂蛋白结合活性。我们的假设是 DPEP 1主要通过其亲脂蛋白结合活性，标志着腺瘤的进展倾向。我们 发现DPEP 1免疫反应性在27%的结直肠腺瘤中检测到，但这一比例增加到72%， 这与DPEP 1标记进展为CRC的腺瘤的小子集一致。利用载人 标本，腺瘤类器官和新鲜分离的中性粒细胞分离的独特的Transwell共培养系统 从健康志愿者和一个信息丰富的小鼠模型，我们将测试是否DPEP 1表达腺瘤更多 有效地与嗜中性粒细胞沟通，创造一个嗜中性粒细胞富集的微环境， 这些腺瘤进展的可能性。外来体作为一种丰富的生物学功能， 可以作为癌症生物标志物的货物来源。我们已经发现DPEP 1在外来体中从 CRC细胞系，并且其高度富集含有已知CRC生物标志物CEA的外来体亚组 关于EPCAM有趣的是，中性粒细胞也释放含有中性粒细胞的小细胞外囊泡（sEV）， 弹性蛋白酶以不能被弹性蛋白酶抑制剂抑制的形式存在，因此它在降解 细胞外基质，癌症侵袭的关键步骤。我们还将使用一种独特的中性粒细胞报告小鼠来监测 中性粒细胞浸润的发生和持续，沿着这些中性粒细胞的性质，在诱导， 干细胞驱动结肠腺瘤小鼠模型。 .

PROJECT SUMMARY/ABSTRACT Project 1: Shaping the Microenvironment by DPEP1 Facilitates Adenoma Progression Project 1 aims to examine how shaping the microenvironment by DPEP1 facilitates adenoma progression. This will be a basic project. We propose that dipeptidase-1 (DPEP1) marks those adenomas with the potential to progress to colorectal cancer (CRC) through an active bi-directional communication with neutrophils. DPEP1 has two functions: dipeptidase activity and recently identified neutrophil-binding activity. Our hypothesis is that DPEP1, largely through its neutrophil-binding activity, marks adenomas with a predilection for progression. We have found that DPEP1 immunoreactivity is detected in 27% of colorectal adenomas but this increases to 72% of CRCs, consistent with DPEP1 marking the small subset of adenomas that progress to CRC. Utilizing human specimens, a unique Transwell co-culture system of adenoma organoids and freshly isolated neutrophils isolated from healthy volunteers, and an informative mouse model, we will test if DPEP1-expressing adenomas more effectively communicate with neutrophils and create a neutrophil-enriched microenvironment, increasing the likelihood that these adenomas will progress. Exosomes have attracted a great deal of recent attention as a rich source of cargo that may serve as cancer biomarkers. We have found that DPEP1 is released in exosomes from CRC cell lines and that it highly enriched in a subset of exosomes that contain known CRC biomarkers, CEA and EPCAM. Of interest, neutrophils also release small extracellular vesicles (sEVs) that contain neutrophil elastase in a form that cannot be inhibited by elastase inhibitors, and thus it is especially potent in degrading the extracellular matrix, a key step in cancer invasion. We will also use a unique neutrophil reporter mouse to monitor onset and perdurance of neutrophil infiltration, along with the properties of these neutrophils, in an inducible, stem cell-driven mouse model of colonic adenomas. .