The micro-RNA content of extracellular vesicles in papillary thyroid cancer : from identification in mouse thyroid tumor to detection in the plasma of patients

This thesis aims to study extracellular vesicles (EVs) in thyroid cancer (TC) hoping to understand their role in cancer progression and to identify new biomarkers for the differential diagnosis between TC and benign nodules. Using a mouse model mimicking human TC, we isolated and characterized EVs from control and cancerous thyroid tissues. We identified tumor-derived EV-miRNAs by sequencing. More abundant EV-miRNAs were mostly deregulated in tumor cells and could affect immune-related pathways. We thus propose that tumor cells secrete more EVs containing a deregulated miRNA signature and that this could affect the immune microenvironment. Finally, the diagnostic value of a few miRNA candidates was assessed by quantifying their levels in plasma-EVs from patients with thyroid diseases, suggesting the diagnostic potential of EV-enclosed miR-146b-5p and miR-21a-5p (BIFA - Sciences biomédicales et pharmaceutiques) -- UCL, 2022