Most metastasizing tumor cells reach distant sites by entering the circulatory system. Within the bloodstream, they are exposed to severe stress due to loss of adhesion to extracellular matrix, hemodynamic shear forces, and attacks of the immune system, and only a few cells manage to extravasate and to form metastases. We review the current understanding of the cellular and molecular mechanisms that allow tumor cells to survive in the intravascular environment and that mediate and promote tumor cell extravasation. As these processes are critical for the metastatic spread of tumor cells, we discuss implications for potential therapeutic approaches and future research.

中文翻译：

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肿瘤细胞的血管内存活和外渗。

大多数转移性肿瘤细胞通过进入循环系统而到达远处。在血流中，由于与细胞外基质的粘附力丧失，血液动力学剪切力和免疫系统的攻击，它们承受着严重的压力，只有少数细胞设法溢出并形成转移灶。我们回顾了目前对细胞和分子机制的理解，这些机制使肿瘤细胞能够在血管内环境中存活并介导并促进肿瘤细胞的外渗。由于这些过程对于肿瘤细胞的转移扩散至关重要，因此我们讨论了对潜在治疗方法和未来研究的意义。