癌细胞和内皮细胞（ECs）在肿瘤微环境中的相互作用对于肿瘤进展、复发和癌细胞干性发挥至关重要的作用。在这里，我们提供了一个方案，其中包含两种研究这种相互作用的体外方法。我们首先描述了一个间接共培养系统，以研究ECs分泌因子对癌细胞中干性标记物的调节作用。然后我们详细描述一个直接共培养系统，以研究细胞间间质通信。有关使用和执行此方案的完整详细信息，请参考Sewell-Loftin等人1和Guo等人2。版权所有©2023作者。Elsevier Inc.保留所有权利。

The cross talk between cancer cells and endothelial cells (ECs) within the tumor microenvironment plays a critical role in tumor progression, recurrence, and cancer stemness. Here, we present a protocol containing two in vitro approaches to study such interactions. We first describe an indirect co-culture system to study the regulation of stemness markers in cancer cells by secreted factors from ECs. We then detail a direct co-culture system to study juxtracrine communications between the cell types. For complete details on the use and execution of this protocol, please refer to Sewell-Loftin et al.1 and Guo et al.2.Copyright © 2023 The Author(s). Published by Elsevier Inc. All rights reserved.