Exosomes: Potential in Cancer Diagnosis and Therapy.

Arti Shukla,Phillip Munson

doi:10.3390/medicines2040310

Abstract

Exosomes are membrane-bound, intercellular communication shuttles that are defined by their endocytic origin and size range of 30–140 nm. Secreted by nearly all mammalian cell types and present in myriad bodily fluids, exosomes confer messages between cells, proximal and distal, by transporting biofunctional cargo in the form of proteins, nucleic acids, and lipids. They play a vital role in cellular signaling in both normal physiology and disease states, particularly cancer. Exosomes are powerful progenitors in altering target cell phenotypes, particularly in tumorigenesis and cancer progression, with the ability to alter tumor microenvironments and to assist in establishing the pre-metastatic niche. Many aspects of exosomes present them as novel means to identify cancer biomarkers for early detection and therapeutic targets, and using intrinsic and engineered characteristics of exosomes as therapeutic devices to ameliorate the progression of the disease. This review outlines some of the recent and major findings with regard to exosomes in cancer, and their utilization as therapeutic tools.

Highlights

IntroductionThe ability for cells to communicate is quintessential to the biology of multicellular organisms
The ability for cells to communicate is quintessential to the biology of multicellular organisms.Intercellular signaling events are accomplished in many ways and depend on a complex array of networks and processes including direct contact, electrical and chemical components, soluble molecular messengers, or the secretion of membrane-bound vesicles
The content of exosomes is another pivotal feature of their classification and ability to carry information and cargo, as they are enriched in RNA species, proteins, biofunctional lipids, and occasionally DNA [4]

Summary

Introduction

The ability for cells to communicate is quintessential to the biology of multicellular organisms. The membrane of exosomes can present Major Histocompatibility Complex (MHC I/II) molecules and/or antigens, depending on the cell type from which the exosome was secreted These specific proteins and lipid molecules are important tools in the classification of exosomes and are attractive targets for the identification of novel biomarkers [11]. Exosomes are released to the extracellular space upon fusion of the MVB with the plasma membrane This process is mediated by a subset small, vesicular transport regulation GTPases known as Rab27A, Rab, and Rab31 [19], and another reported mechanism for secretion, for exosomes bearing. Target cell specificity is not yet fully understood but is likely determined by adhesion-associated molecules present on the exosomal surface, such as integrins and SNAREs, with the possible influence of tetraspanins complexes [22]. There are several fates of exosomes once bound to a recipient cell, prompting what signaling information is delivered: the exosome can bind and associate with a membrane receptor or dissociate; direct fusion with the plasma membrane and unloading of cargo to the target cytosol; or endocytic internalization [3]

Exosomes and Cancer

Exosomes in Therapy

Conclusions