摘要Despite continual progress in the technologies and regimens for cancer therapy,the treatment outcome of fatal metastatic breast cancer is far from satisfactory.Encouragingly,nanotechnology has emerged as a valuable tool to optimize drug delivery process in cancer therapy via preventing the cargos from degradation,improving the tumor-targeting efficiency,enhancing therapeutic agents'retention in specific sites,and controlling drug release.In the last decade,several mechanisms of suppressing tumor metastasis by functional nano drug delivery systems(NDDSs)have been revealed and a guidance for the rational design of anti-metastasis NDDSs is summarized,which consist of three aspects:optimization of physi-ochemical properties,tumor microenvironment remodel-ing,and biomimetic strategies.A series of medicinal functional biomaterials and anti-metastatic breast cancer NDDSs constructed by our team are introduced in this re-view.It is hoped that better anti-metastasis strategies can be inspired and applied in clinic.