Abstract

Relevance of EV Heterogeneity For Their Application in Liquid Biopsy

Irina Nazarenko, Exosome and Tumor Biology Group Head, University of Freiburg

The need to develop better approaches allowing comprehensive molecular characterization of a progressing tumor has led to the development of the “Liquid Biopsy” concept, which is based on the application of body fluids as a biomarker source. In view on the complexity of blood and availability of components of different origins, including circulating tumor cells, free-circulating nucleic acids and Extracellular Vesicles (EVs), a question of a specific impact of each of these different compartments on the outcome of liquid biopsy-based diagnostic may arise. We address this question comparing amounts of mutated oncogenes in different EV subtypes and in the free-circulating fractions in blood of cancer patients. Our results show that different tumor types at different stages may contain varying portions of potential biomarkers in the free circulating fraction and in different EV subtypes, indicating a potential relevance of a comparative analysis of different blood compartments prior the choice of the most appropriate source and technique for the liquid biopsy-based diagnostic.