Microscopic membranous vesicles floating outside of cells were first discovered 50 years ago; 30 years later, a subset of these was coined exosomes. At the time, these membrane bubbles were believed to be nothing more than a cellular waste disposal mechanism. But within the past decade, extracellular vesicles – and exosomes in particular – have piqued scientists’ interests, resulting in a research boom.
In 2006, there were just 115 publications referencing exosomes; by 2015, this number had mushroomed to 1010. Today, a PubMed search brings up more than 7500 publications. Consulting firm Grand View Research estimates that the global exosome market could reach $2.28bn by 2030.
Advancements in exosome research could lead to breakthroughs in prostate cancer treatment.
The interest in exosomes has been driven by the new finding that exosomes are more than just a waste disposal system – they are also a means of communication between cells and have the ability to carry cargos such as proteins and mRNA, suggesting there could be potential medical applications.
‘Currently, research into exosomes and other extracellular vesicles is very strong,’ says Jason Webber, Prostate Cancer UK research fellow in the Division of Cancer and Genetics at Cardiff University. ‘I think this field of research will continue to grow and I believe we’ll also see greater clinical application of exosomes and a drive towards research exploring the therapeutic potential of exosomes.’
Exosomes in Cancer Research. Video: Thermo Fisher Scientific
Exosomes are best described as extracellular vescles – essentially membrane sacs – formed by the inward budding of the membrane of intracellular compartments known as multivesicular bodies (MVBs) or multivesicular endosomes (MVEs). They are released from cells when MVBs fuse with the cell’s plasma membrane, releasing its contents outside the cell. These vesicles, made of a phospholipid bilayer and ranging between 40nm and 150nm in diameter, are found in all biological fluids including blood, urine, saliva, bile, semen and breast milk.