Cascade Delivery to Golgi Apparatus and On‐Site Formation of Subcellular Drug Reservoir for Cancer Metastasis Suppression

Abstract As the foremost cause of cancer‐related death, metastasis consists of three steps: invasion, circulation, and colonization. Only targeting one single phase of the metastasis cascade may be insufficient since there are many alternative routes for tumor cells to disseminate. Here, to target the whole cascade of metastasis, hybrid erythrocyte and tumor cell membrane‐coated nanoparticle (Hyb‐NP) is designed with dual functions of increasing circulation time and recognizing primary, circulating, and colonized tumors. After loading with monensin, a recently reported metastasis inhibitor, the delivery system profoundly reduces spontaneous metastasis in an orthotopic breast cancer model. Underlying mechanism studies reveal that Hyb‐NP can deliver monensin to its action site in the Golgi apparatus, and in return, monensin can block the exocytosis of Hyb‐NP from the Golgi apparatus, forming a reservoir‐like subcellular structure. Notably, the Golgi apparatus reservoir displays three vital functions for suppressing metastasis initialization, including enhanced subcellular drug retention, metastasis‐related cytokine release inhibition, and directional migration inhibition. Collectively, based on metastasis cascade targeting at the tissue level, further formation of the Golgi apparatus drug reservoir at the subcellular level provides a potential therapeutic strategy for cancer metastasis suppression.