Live Macrophage-Delivered Doxorubicin-Loaded Liposomes Effectively Treat Triple-Negative Breast Cancer.

Triple-negative breast cancer is often aggressive and resistant to various cancer therapies, especially corresponding targeted drugs. It is shown that targeted delivery of chemotherapeutic drugs to tumor sites could enhance treatment outcome against triple-negative breast cancer. In this study, we exploited the active tumor-targeting capability of macrophages by loading doxorubicin-carrying liposomes on their surfaces via biotin-avidin interactions. Compared with conventional liposomes, this macrophage-liposome (MA-Lip) system further increased doxorubicin accumulation in tumor sites, penetrated deeper into tumor tissue, and enhanced antitumor immune response. As a result, the MA-Lip system significantly lengthened the survival rate of 4T1 cell-bearing mice with low toxicity. Besides, the MA-Lip system used highly biocompatible and widely approved materials, which ensured its long-term safety. This study provides a system for triple-negative breast cancer treatment and offers another macrophage-based strategy for tumor delivery.