E loaded with chemotherapic drugs, and exosomes isolated in the conditioned medium exert a pro-apoptotic 4′-Hydroxy Fenretinide-d4 In Vitro effect on tumor cells [134,135]. Furthermore,Int. J. Mol. Sci. 2021, 22,9 ofMSC could be loaded with synthetic miRNAs which will be transferred into recipient cells and suppress migration of OS cells [136,137]. In some circumstances, the apoptotic effect was elevated following the remedy with drug EVs in comparison to that observed having a cost-free drug at the similar concentration contained in the EVs [37], confirming that EV itself can exert an apoptotic stimulus [128]. 3.5. EVs for