Exosome-Encased Nucleic Acid Scaffold Chemotherapeutic Agents for Superior Anti-Tumor and Anti-Angiogenesis Activity.

Extracellular vesicles (EVs), or exosomes, play a pivotal role in tumor growth and metastasis, such as in the case of Kaposi Sarcoma. By loading tumor-derived EVs with chemotherapeutic drugs, we noted that their pro-tumor/pro-angiogenic phenotype was converted into an anti-tumor phenotype in vivo . Drug concentration in EVs was significantly higher than in clinically approved liposome formulation, as retention was facilitated by the presence of miRNAs inside the natural EVs. This demonstrates a new mechanism by which to increase the payload capacity of nanoparticles. By exploiting the targeting preferences of tumor-derived EVs, chemotherapeutics can be directed to specifically poison the cells and the microenvironment that enables metastasis.