在转移级联中，循环中的存活、从血管外渗和定居新组织是转移性肿瘤细胞的主要步骤，对其构成了巨大的挑战。在血液和淋巴管中循环的肿瘤细胞需要克服失重死亡，应对剪切应力等机械刺激，以及击败免疫系统的攻击。一旦附着在血管壁上，循环的肿瘤细胞（CTC）就可以欺骗内皮细胞使其放松细胞之间的连接，以便肿瘤细胞渗入内皮。由于肿瘤细胞倾向于转移至命名的靶器官和组织，称为靶向性器官转移，因此转移的分布绝不是随机的。潜在的细胞生理学机制包括离子通道/转运体的存在和活性，由于后者在细胞生理过程中发挥着关键作用。到目前为止，只有极少数研究明确显示了离子转运的参与。本综述描述了离子通道和转运体对已知和可能对CTC存活、外渗和器官特异性物质贡献。此外，还探讨了离子转运与CTC行为之间的假设联系，并暗示了潜在的治疗应用前景。©2021.作者（s）独家许可，授权Springer Nature Switzerland AG.

Survival in the circulation, extravasation from vasculature, and colonizing new tissues represent major steps of the metastatic cascade and pose a big challenge for metastasizing tumor cells. Tumor cells circulating in blood and lymph vessels need to overcome anoikis, cope with mechanical stimuli including shear stress, and defeat attacks by the immune system. Once adhered to the vessel wall, a circulating tumor cell (CTC) can trick the endothelial cells into loosening their intercellular junctions so that the endothelium becomes penetrable for the tumor cell. Since tumor cells tend to metastasize to predestinated target organs and tissues, called organotropism, the distribution of metastases is anything but random. The molecular-physiological mechanisms underlying CTC survival, extravasation, and organotropism are very likely to include the presence and activity of ion channels/transporters due to the latter's key function in cytophysiological processes. To date, a very limited number of studies explicitly show the involvement of ion transport. This review describes the contribution of ion channels and transporters to CTC survival, extravasation, and organotropism where known and possible. In addition, supposed connections between ion transport and CTC behavior are demonstrated and imply the potential to be therapeutically taken advantage of.© 2021. The Author(s), under exclusive license to Springer Nature Switzerland AG.