Tumors can shed thousands of cells into the circulation daily. These circulating tumor cells (CTCs) are heterogeneous, and their phenotypes change dynamically. Real-time monitoring of CTC phenotypes is crucial to elucidate the role of CTCs in the metastatic cascade. Here, we monitor phenotypic changes in CTCs in mice xenografted with tumors with varying aggressiveness during cancer progression and a course of chemotherapy to study the metastatic potential of CTCs and changes in the properties of these cells in response to treatment. A new device that enables magnetic ranking cytometry (MagRC) is employed to profile the phenotypic properties of CTCs. Overall, CTCs from metastatic xenografts in mice display dynamic and heterogeneous profiles while non-metastatic models had static profiles. Decreased heterogeneity followed by a reduction in metastasis incidence was observed after a course of chemotherapy administered to highly metastatic xenografts. Phenotypic profiling of CTCs could be employed to monitor disease progression and predict therapeutic responses.

中文翻译：

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使用磁排序细胞术可视化转移性前列腺癌模型中的动态 CTC 表型†

肿瘤每天可以将数千个细胞释放到循环系统中。这些循环肿瘤细胞（CTC）是异质的，它们的表型动态变化。实时监测 CTC 表型对于阐明 CTC 在转移级联中的作用至关重要。在这里，我们监测异种移植有不同侵袭性肿瘤的小鼠在癌症进展和化疗过程中 CTC 的表型变化，以研究 CTC 的转移潜力以及这些细胞对治疗的反应特性的变化。采用磁排序细胞术 (MagRC) 的新设备来分析 CTC 的表型特性。总体而言，小鼠转移性异种移植物的 CTC 显示出动态和异质特征，而非转移模型则具有静态特征。对高度转移的异种移植物进行一个疗程的化疗后，观察到异质性降低，继而转移发生率降低。CTC 的表型分析可用于监测疾病进展和预测治疗反应。