Exosomes in the tumor microenvironment as mediators of cancer therapy resistance

Irene Li,Barzin Y Nabet

doi:10.1186/s12943-019-0975-5

Abstract

Exosomes are small extracellular vesicles that contain genetic material, proteins, and lipids. They function as potent signaling molecules between cancer cells and the surrounding cells that comprise the tumor microenvironment (TME). Exosomes derived from both tumor and stromal cells have been implicated in all stages of cancer progression and play an important role in therapy resistance. Moreover, due to their nature as mediators of cell-cell communication, they are integral to TME-dependent therapy resistance. In this review, we discuss current exosome isolation and profiling techniques and their role in TME interactions and therapy resistance. We also explore emerging clinical applications of both exosomes as biomarkers, direct therapeutic targets, and engineered nanocarriers. In order to fully understand the TME, careful interrogation of exosomes and their cargo is critical. This understanding is a promising avenue for the development of effective clinical applications.

Highlights

The tumor microenvironment (TME) is a complex ecosystem and an active participant in all stages of cancer initiation and progression [1, 2]
We focus on our growing understanding of the biogenesis and functions of exosomes originating from cancer cells and the TME and their ability to mediate paracrine signaling and influence cancer progression
Fibroblasts secrete non-coding RNA (ncRNA)-containing exosomes, which upregulate anti-viral signaling in recipient breast cancer cells by activating the RIG-I pattern recognition receptor (PRR) [57]

Summary

Introduction

The tumor microenvironment (TME) is a complex ecosystem and an active participant in all stages of cancer initiation and progression [1, 2]. We focus on our growing understanding of the biogenesis and functions of exosomes originating from cancer cells and the TME and their ability to mediate paracrine signaling and influence cancer progression. The TME can amplify critical oncogenic pathways in cancer cells to promote tumor progression, dissemination, and therapy resistance.

Results

Conclusion