Figure 5.

Potential clinical application of exosomes. Exosomes are produced by living cells, carry a variety of active molecules, and are ubiquitously present in various body fluids. Exosomes may be detected in the microenvironment before tumour metastasis and reflect tumour proliferation and metastasis; therefore, they can be used as biomarkers for early diagnosis and prognosis of tumours. Because of specialized vesicle structure, exosomes are stable carriers of therapeutic drugs with increased targeting ability. Therapeutic exosomes can be divided into two categories: natural exosomes secreted directly in body fluids and artificially engineered exosomes.