THYROID TUMOR CELLS-FIBROBLASTS INTERACTION PRODUCES EXTRACELLULAR VESICLES INVOLVED IN THYROID TUMOR AGGRESSIVENESS

BRAVO MIANA, R; NEGRETTI, DM; SOLER, MF; DE PAUL, AL; GILARDONI, MB; MONTESINOS, MM; PELLIZAS, CG; DONADIO, AC

Buenos Aires

Congreso; XVII Latin American Thyroid Congress; 2019

Latin American Thyroid Society

Introduction: Carcinomas are complex societies of mutually interacting cells. Extracellular vesicles (EVs) mediate intercellularcommunication in the tumor microenvironment (TM). Metalloproteinases (MMPs) activity and Galectin-1 (Gal-1) expression in TMregulate tumor-stroma crosstalk leading to tumor progression and aggressiveness. We demonstrated that thyroid tumor cells- fibroblasts(Fb) interactions induce the secretion of MMPs to culture supernatants (CMs) and a migratory phenotype in tumor cells. Objectives:To characterise EVs released by Fb and thyroid cells, and their role mediating a thyroid tumor-promoting environment. Methods:Thyroid tumor cells (TPC-1, 8505c) or thyroid non-tumor cells (NThyOri) were co-cultured with normal human Fb as a simulation ofthe thyroid TM. EVs, obtained by ultracentrifugation of thyroid cells, Fb and thyroid cells-Fb CMs were characterised by TransmissionElectron Microscopy and Western blot. MMPs activity was analysed by zymography in EVs, and in CMs from Fb and NThyOri cellsincubated with EVs. Gal-1 expression was evaluated by RT-qPCR in EVs-stimulated Fb. Results: Isolated and co-cultured cellssecreted EVs to CMs. EVs have the characteristic cup-shaped morphology, size (