Figure 1. BMSC-derived exosomes transport lncRNA PVT1 into osteosarcoma cells. The BMSC-derived exosomes (BMSC-EXO) and the osteosarcoma cell MNNG/HOS-derived exosomes (MNNG-EXO) in the culture medium were respectively isolated. (A) They were observed under the transmission electron microscopy. (B) The expression of CD81 and CD63 proteins, both of which were exosome markers, was detected using western blot analysis. (C) The expression of PVT1 was detected using qRT-PCR. The osteosarcoma cell lines, including Saos-2, MG-63, and MNNG/HOS, were co-cultured with 40 μg/mL BMSC-EXO or MNNG-EXO for 48 h. (D) The expression of PVT1 in osteosarcoma cells. (E) BMSCs were transfected with si-PVT1 for 48 h. The expression of PVT1 in exosomes which were isolated from PVT1-interfering BMSCs was detected. (F) The expression of PVT1 in osteosarcoma cells, which were co-cultured with BMSC-EXOsi-PVT1 or BMSC-EXOsi-control for 48 h. Three independent experiments. **p<0.01 vs MNNG-EXO or si-control. PBS, phosphate buffer saline was used as the control of both kinds of exosomes. si-PVT1, small interfering RNA of PVT1.