The biodistribution and immune suppressive effects of breast cancer-derived exosomes

Abstract

Small membranous secretions from tumor cells, termed exosomes, contribute significantly to intercellular communication and subsequent reprogramming of the tumor microenvironment. Here, we use optical imaging to determine that exogenously administered fluorescently labeled exosomes derived from highly metastatic murine breast cancer cells distributed predominantly to the lung of syngeneic mice, a frequent site of breast cancer metastasis. At the sites of accumulation, exosomes were taken up by CD45+ bone marrow-derived cells. Subsequent long-term conditioning of naïve mice with exosomes from highly metastatic breast cancer cells revealed the accumulation of myeloid-derived suppressor cells in..