Proteomic Analysis of Exosomes Reveals an Association between Cell Invasiveness and Exosomal Bioactivity on Endothelial and Mesenchymal Cell Migration In-Vitro

In this study, we explored the effect of exosomes on cells present in the tumour microenvironment. Exosomes were isolated from ovarian cancer cells with different invasive capacity (high=SKOV-3 and low=OVCAR-3) by differential and buoyant density centrifugation and characterized using nanoparticle tracking analysis, western blot and electron microscopy. Exosome secretion was positively correlated with invasiveness of releasing cells. Proteomic analyses identified common and unique proteins between exosomes from SKOV-3 and OVCAR-3 with gene ontology analyses revealing that these exosomes are involved in the regulation of cell migration. Since the tumour microenvironment contains multiple cell types, including mesenchymal stem cells and endothelial cells, we examined the effect of these exosomes on MSC and EC migration. Exosomes promoted MSC and EC migration in a time- and concentration-dependent manner. The effect of exosomes isolated from SKOV-3 on cell migration was significantly higher compared to exosomes from OVCAR-3. Thus, we suggest that exosomes from ovarian cancer cells contain a specific set of proteins that are representative of its cell of origin and the invasive capacity.

Source: Clinical Science - August 17, 2018 Category: Biomedical Science Authors: Sharma, S., Alharbi, M., Kobayashi, M., Lai, A., Guanzon, D., Zuniga, F., Ormazabal, V., Palma, C., Scholz-Romero, K., Rice, G. E., Hooper, J. D., Salomon, C. Tags: PublishAheadOfPrint Source Type: research