The article "Extracellular Vesicle-Mediated Pre-Metastatic Niche Formation via Altering Host Microenvironments" by Ying Li, Yan Zheng, Xiaojie Tan, Yongxing Du, Yingxin Wei, and Shanglong Liu, published in *Frontiers in Immunology* in March 2024, explores the role of extracellular vesicles (EVs) in cancer metastasis. EVs, which are small membrane-bound vesicles produced by various cell types, play a crucial role in cancer progression by facilitating bidirectional communication between tumor cells and the host microenvironment. The authors discuss how EVs alter the host microenvironment to create pre-metastatic niches (PMNs), which are pre-established microenvironments that support the colonization of circulating tumor cells (CTCs) in distant organs. Key points include: 1. **EV Biogenesis and Composition**: EVs are categorized into exosomes, microvesicles, and apoptotic bodies. They carry various biologically active molecules such as DNA, RNAs, lipids, proteins, and metabolites. 2. **EV-Mediated Communication**: EVs mediate communication between tumor cells and stromal cells, promoting angiogenesis, matrix remodeling, and immunosuppression. 3. **PMN Formation**: PMNs are pre-established microenvironments that support the outgrowth of tumor cells in distant organs. They are formed through interactions between cancer cells and the host microenvironment, influenced by factors like hypoxia, inflammation, and cytokines. 4. **Organotropism**: The origin of primary tumors determines the pattern of metastatic organs. EVs target recipient cells via docking on surface receptors or entering cells through endocytosis, influencing organ-specific metastasis. 5. **Mechanisms of PMN Establishment**: EVs enhance angiogenesis, vascular remodeling, stromal reprogramming, immunosuppression, and metabolic remodeling to facilitate PMN formation. 6. **Targeting EVs for Therapy**: The article discusses potential therapeutic strategies, including targeting EV production, removing circulating EVs, and preventing EV interactions with recipient cells. The review highlights the importance of EVs in cancer metastasis and suggests that targeting EVs may be a promising approach for preventing and treating metastasis.The article "Extracellular Vesicle-Mediated Pre-Metastatic Niche Formation via Altering Host Microenvironments" by Ying Li, Yan Zheng, Xiaojie Tan, Yongxing Du, Yingxin Wei, and Shanglong Liu, published in *Frontiers in Immunology* in March 2024, explores the role of extracellular vesicles (EVs) in cancer metastasis. EVs, which are small membrane-bound vesicles produced by various cell types, play a crucial role in cancer progression by facilitating bidirectional communication between tumor cells and the host microenvironment. The authors discuss how EVs alter the host microenvironment to create pre-metastatic niches (PMNs), which are pre-established microenvironments that support the colonization of circulating tumor cells (CTCs) in distant organs. Key points include: 1. **EV Biogenesis and Composition**: EVs are categorized into exosomes, microvesicles, and apoptotic bodies. They carry various biologically active molecules such as DNA, RNAs, lipids, proteins, and metabolites. 2. **EV-Mediated Communication**: EVs mediate communication between tumor cells and stromal cells, promoting angiogenesis, matrix remodeling, and immunosuppression. 3. **PMN Formation**: PMNs are pre-established microenvironments that support the outgrowth of tumor cells in distant organs. They are formed through interactions between cancer cells and the host microenvironment, influenced by factors like hypoxia, inflammation, and cytokines. 4. **Organotropism**: The origin of primary tumors determines the pattern of metastatic organs. EVs target recipient cells via docking on surface receptors or entering cells through endocytosis, influencing organ-specific metastasis. 5. **Mechanisms of PMN Establishment**: EVs enhance angiogenesis, vascular remodeling, stromal reprogramming, immunosuppression, and metabolic remodeling to facilitate PMN formation. 6. **Targeting EVs for Therapy**: The article discusses potential therapeutic strategies, including targeting EV production, removing circulating EVs, and preventing EV interactions with recipient cells. The review highlights the importance of EVs in cancer metastasis and suggests that targeting EVs may be a promising approach for preventing and treating metastasis.