Cancer metastasis and therapy resistance are intricately linked with the dynamics of Epithelial-Mesenchymal Transition (EMT) and Circulating Tumor Cells (CTCs). EMT hybrid cells, characterized by a blend of epithelial and mesenchymal traits, have emerged as pivotal in metastasis and demonstrate remarkable plasticity, enabling transitions across cellular states crucial for intravasation, survival in circulation, and extravasation at distal sites. Concurrently, CTCs, which are detached from primary tumors and travel through the bloodstream, are crucial as potential biomarkers for cancer prognosis and therapeutic response. There is a significant interplay between EMT hybrid cells and CTCs, revealing a complex, bidirectional relationship that significantly influences metastatic progression and has a critical role in cancer drug resistance. This resistance is further influenced by the tumor microenvironment, with factors such as tumor-associated macrophages, cancer-associated fibroblasts, and hypoxic conditions driving EMT and contributing to therapeutic resistance. It is important to understand the molecular mechanisms of EMT, characteristics of EMT hybrid cells and CTCs, and their roles in both metastasis and drug resistance. This comprehensive understanding sheds light on the complexities of cancer metastasis and opens avenues for novel diagnostic approaches and targeted therapies and has significant advancements in combating cancer metastasis and overcoming drug resistance.

中文翻译：

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交叉途径：混合 E/M 细胞和循环肿瘤细胞在癌症转移和耐药性中的作用


癌症转移和治疗耐药与上皮间质转化（EMT）和循环肿瘤细胞（CTC）的动态密切相关。 EMT 杂交细胞具有上皮和间质特征的混合特征，已成为转移的关键，并表现出显着的可塑性，能够实现对内渗、循环存活和远端外渗至关重要的细胞状态的转变。同时，CTC 与原发肿瘤分离并通过血流传播，作为癌症预后和治疗反应的潜在生物标志物至关重要。 EMT 杂交细胞和 CTC 之间存在显着的相互作用，揭示了一种复杂的双向关系，可显着影响转移进展，并在癌症耐药性中发挥关键作用。这种耐药性进一步受到肿瘤微环境的影响，肿瘤相关巨噬细胞、癌症相关成纤维细胞和缺氧条件等因素会驱动 EMT 并导致治疗耐药性。了解 EMT 的分子机制、EMT 杂交细胞和 CTC 的特征及其在转移和耐药性中的作用非常重要。这种全面的理解揭示了癌症转移的复杂性，为新的诊断方法和靶向治疗开辟了途径，并在对抗癌症转移和克服耐药性方面取得了重大进展。