Characterization of extracellular vesicles secreted by head and neck squamous cell carcinoma cell lines sensitive and resistant to gefitinib

Abstract

Head and Neck Squamous Cell Carcinoma (HNSCC) is one of the most common tumors, with high incidence and mortality in the world. Although EGFR is overexpressed and correlated to the worst prognosis in 90% of the HNSCC cases, only a small subpopulation of patients has shown excellent response to TKIs (gefitinib), which does not correlate with EGFR expression or amplification. Extracellular vesicles (EVs), describes different classes of particles enveloped by a lipid bilayer, such as microvesicles, membrane particles, apoptotic bodies and exosomes. EVs carry several bioactive molecules, such as nucleic acids, proteins, lipids and metabolites, and play an important role in intercellular communication because of their ability to transfer molecules between distant cells. Detection and analysis of EVs secreted by tumor cells may be useful for the development of noninvasive methods of monitoring the response to a particular therapy. Thus the objective of this study was to purify and characterize the extracellular vesicles secreted by sensitive and resistant HNSCC cells to gefitinib. (AU)