慢速循环亚群在抗癌药物耐药和肿瘤复发中发挥着重要作用。在这里，我们描述了一个临床相关的患者异种移植模型和一种在细胞增殖依赖性方式下稀释的荧光素苯酰亚胺染料。我们详细介绍了分离异质性肿瘤群中活跃循环癌细胞和慢速循环癌细胞（SCCs）的步骤，以确认它们不同的细胞特性。该方案可用于区分SCCs、研究它们的生物学，并开发抗癌治疗策略。关于使用和执行该方案的完整细节，请参考Cho等人的文章（2021）。1.版权所有©2023 The Authors。由Elsevier Inc.出版，保留所有权利。

The slow-cycling subpopulation plays an important role in anticancer drug resistance and tumor recurrence. Here, we describe a clinically relevant patient-derived xenograft model and a carboxyfluorescein succinimidyl ester dye that is diluted in a cell proliferation-dependent manner. We detail steps to separate active-cycling cancer cells and slow-cycling cancer cells (SCCs) in heterogeneous cancer populations to confirm their different cellular properties. This protocol can be used to distinguish SCCs, investigate their biology, and develop strategies for anticancer therapeutics. For complete details on the use and execution of this protocol, please refer to Cho et al. (2021).1.Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.