Fig. 2

Exosomes cause therapy resistance in recipient and donor cells Exosomes transport multi drug resistance (MDR) transporter to recipient cells causing increased efflux of drugs by integrating MDR transporter in the cell membrane. Furthermore, exosomes cause increased anti-apoptotic signaling and DNA repair in the recipient cell. Besides these effects on recipient cells exosomes are important for therapy resistance of the donor cell as well. MDR transporters are incorporated into the exosomal membrane with reverse orientation, which promotes the influx of drugs from the donor cell into the exosome reducing intracellular drug concentration. Exosomes also reduce intracellular concentration of pro-apoptotic signalling factors by transporting them away from the donor cell