Role of exosomes and exosomal microRNAs in cancer

Abstract

A growing body of evidence indicates that exosomes play a critical role in the cell-cell communication process. Exosomes are biological nanoparticles with an average diameter of 30-100 nm in size and are produced by almost all cell types in the human body; however, cancer cells contain higher concentrations of exosomes than healthy cells. They are released into all body fluids and contain double-stranded DNA (originated from nucleus and mitochondria), a variety of RNA species, and specific protein biomarkers that can be utilized as cancer biomarkers and therapeutic targets, and lipids. Therefore, the specific exosomes secreted by tumor cells could be used to predict the existence of the presence of a tumor in cancer patients. This review summarizes the role of exosomes in cancer development and their potential utility in the clinic. Lay abstract Intercellular communication between tumor cells and their neighboring cells and distant organs is key to cancer's survival, progression, drug resistance and metastasis. Circulating exosomes carry a specific composition of proteins, lipids, RNA and DNA and can work as cargo to transfer this information from donor cells to target cells, leading to reprogramming of the recipient cells. Exosomes are small particles with big roles in cancer. The present review summarizes the significant aspects of exosomes in cancer development and how they might provide novel strategies for use in the clinic.