Concise review: The role of cancer-derived exosomes in tumorigenesis and immune cell modulation

Abstract

Exosomes are subcellular entities which were first discovered in the 1980s. Over the past decade, scientists have discovered that they carry components of genetic information that allow for cell-cell communication and cell targeting. Exosomes secreted by cancer cells are termed cancer-derived exosomes (CDEs), and play an important role in tumor formation and progression. Specifically, CDEs mediate the communication between cancer cells, as well as between cancer cells and other cells in the tumor microenvironment, including cancer-associated fibroblasts, endothelial cells, mesenchymal stem cells, and effector immune cells. Additionally, through the vascular system and body fluids, CDEs can modulate response to drugs, increase angiogenesis, stimulate proliferation, promote invasion and metastasis, and facilitate escape from immune surveillance. This review will discuss the relationship between cancer cells and other cells (particularly immune cells), as mediated through CDEs, as well as the subsequent impact on tumorigenesis and immunomodulation. Understanding the role of CDEs in tumorigenesis and immune cell modulation will help advance their utilization in the diagnosis, prognosis, and treatment of cancer.