Fig. 2

ADR/exo transfer chemoresistance to recipient cells. a The uptake of the fluorescently labelled Exo/ADR was evident in 90% MCF-7 cells after 12 h of incubation. No stain was revealed in the negative control condition (PBS). b Drug-resistance-related mRNA changes (MDR-1, MRP and LRP) in MCF-7 incubated with ADR/exo. ADR/exo induced a increase of MDR-1, MRP and LRP mRNA levels compared to MCF-7 and MCF-7 + S/exo cells, especially the MDR-1 (p < 0.05). c IC50 of adriamycin was determined by MTT. The results showed that MCF-7 cells after incubation with ADR/exo displayed 5.5 fold greater resistance to adriamycin than MCF-7 cells. MCF-7 + ADR/exo had greater resistance to adriamycin, p < 0.05 compared to MCF-7 cells. d Confocal micrographs showing adriamycin localization in MCF-7+ ADR/exo cells. Scale bars, 25 μm