For decades, cancer metastasis has been a heated topic for its high mortality. Previous research has shown that pre-metastatic niche and metastatic niche are the 2 crucial steps in cancer metastasis, assisting cancerous cells’ infiltration, survival, and colonization at target sites. More recent studies have unraveled details about the specific mechanisms related to the modification of pro-invasion environments. Here, we will review literatures on extracellular matrix (ECM) alterations, general cancer metastasis, organ specificity, pre-metastatic niche, metastatic niche, colony formation and impact on the course of metastasis. Respectively, the metastatic mechanisms like effect of hypoxia or inflammation on pre-metastatic niche construction, as well as the interaction between cancer cells and local milieu will be discussed. Based on the evidences of metastatic niches, we revisit and discussed the “Seed and Soil” hypothesis by Paget. This review will seek to provide insight into the mechanism of metastatic organ specificity which pre-metastatic niche and metastatic niche might suggest from an evolutionary aspect.

中文翻译：

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肿瘤转移的关键步骤：肿瘤微环境和细胞外基质的改变在转移前和转移生态位的形成中。


几十年来，癌症转移因其高死亡率一直是一个热门话题。先前的研究表明，转移前生态位和转移生态位是癌症转移的两个关键步骤，有助于癌细胞在靶位点的浸润、存活和定植。最近的研究揭示了与改变促入侵环境相关的具体机制的细节。在这里，我们将回顾关于细胞外基质（ECM）改变、一般癌症转移、器官特异性、转移前生态位、转移生态位、集落形成以及对转移过程的影响的文献。将分别讨论缺氧或炎症对转移前微环境构建的影响等转移机制，以及癌细胞与局部环境之间的相互作用。基于转移生态位的证据，我们重新审视并讨论了佩吉特的“种子和土壤”假说。本综述将寻求深入了解转移器官特异性的机制，转移前生态位和转移生态位可能从进化方面提示。