EPCAM and neoplasm: EVs can be classified based on their origin into tumor-derived EVs or mesenchymal stem cell (MSC)-derived EVs (MSC-EVs); their functions into pro-apoptotic EVs or immune-suppressing/stimulating EVs, and based on the presence of specific surface biomarkers, such as CD63+, CD9+, CD81+, or EpCAM+ EVs 37.