已有研究报道，肿瘤衍生的细胞外囊泡（EVs）含有包括DNA在内的核酸。几项研究已经突出了EV衍生的DNA（evDNA）作为循环生物标志物的潜力，甚至证明了在灵敏度方面，evDNA可以超越游离DNA（cfDNA）。在此，我们评估了EVs作为晚期胰腺癌患者肿瘤衍生DNA的潜在来源。分析了经DNase处理和未经处理的EV样本中的evDNA，以确定DNA主要位于EV内部还是外部（表面结合）。为了评估方法对结果的影响，我们使用了四种不同的小型EV分离方法以及差速离心法来分离大型EVs。我们的结果表明，与从相同血浆体积中分离的cfDNA相比，EV中的DNA含量明显较少（p <0.001）。大部分检测到的evDNA也位于囊泡的外部。此外，EV中肿瘤来源DNA的比例与cfDNA中的相似。总之，我们的结果表明，在至少晚期胰腺癌患者中，作为肿瘤来源DNA的一种来源，evDNA的定量并不能为cfDNA所获取的信息增添任何内容。版权：© 2023 Lapin等人。本文是根据创作共用许可证分发的开放获取文章，只要原作者和来源被指明，就可以在任何媒体中自由使用、分发和再现。

Tumor-derived extracellular vesicles (EVs) are reported to contain nucleic acids, including DNA. Several studies have highlighted the potential of EV-derived DNA (evDNA) as a circulating biomarker, even demonstrating that evDNA can outperform cell-free DNA (cfDNA) in terms of sensitivity. Here, we evaluated EVs as a potential source of tumor-derived DNA in patients with advanced pancreatic cancer. evDNA from both DNase-treated and untreated EV samples was analyzed to determine whether the DNA was primarily located internally or outside (surface-bound) the EVs. To assess whether methodology affected the results, we isolated EVs using four different methods for small EV isolation and differential centrifugation for isolating large EVs. Our results indicated that the DNA content of EVs was significantly less than the cfDNA content isolated from the same plasma volume (p < 0.001). Most of the detected evDNA was also located on the outside of the vesicles. Furthermore, the fraction of tumor-derived DNA in EVs was similar to that found in cfDNA. In conclusion, our results suggest that quantification of evDNA, as a source of tumor-derived DNA, does not add information to that obtained with cfDNA, at least not in patients with advanced pancreatic cancer.Copyright: © 2023 Lapin et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.