Circulating tumour cells (CTCs) have recently been identified as valuable biomarkers for diagnostic and prognostic evaluations, as well for monitoring therapeutic responses to treatments. CTCs are rare cells which may be present as one CTC surrounded by approximately 1 million white blood cells and 1 billion red blood cells per millilitre of peripheral blood. Despite the various challenges in CTC detection, considerable progress in detection methods have been documented in recent times, particularly for methodologies incorporating nanomaterial-based platforms and/or integrated microfluidics. Herein, we summarize the importance of CTCs as biological markers for tumour detection, highlight their mechanism of cellular invasion and discuss the various challenges associated with CTC research, including vulnerability, heterogeneity, phenotypicity and size differences. In addition, we describe nanomaterial agents used for electrochemistry and surface plasmon resonance applications, which have recently been used to selectively capture cancer cells and amplify signals for CTC detection. The intrinsic properties of nanomaterials have also recently been exploited to achieve photothermal destruction of cancer cells. This review describes recent advancements and future perspectives in the CTC field.

中文翻译：

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循环肿瘤细胞：广阔的前景

循环肿瘤细胞 (CTC) 最近被确定为诊断和预后评估以及监测治疗反应的有价值的生物标志物。CTC 是一种罕见的细胞，它可能以一个 CTC 的形式存在，每毫升外周血大约有 100 万个白细胞和 10 亿个红细胞。尽管 CTC 检测面临各种挑战，但最近已经记录了检测方法的相当大的进步，特别是对于结合基于纳米材料的平台和/或集成微流体的方法。在此，我们总结了 CTC 作为肿瘤检测生物标志物的重要性，强调了它们的细胞侵袭机制，并讨论了与 CTC 研究相关的各种挑战，包括脆弱性、异质性、表型和大小差异。此外，我们描述了用于电化学和表面等离子共振应用的纳米材料试剂，它们最近被用于选择性捕获癌细胞并放大信号以进行 CTC 检测。最近还利用纳米材料的内在特性来实现对癌细胞的光热破坏。这篇综述描述了 CTC 领域的最新进展和未来前景。