Skip to main content
. 2022 Apr 13;34:100429. doi: 10.1016/j.jbo.2022.100429

Fig. 7.

Fig. 7

Luteolin modulates chemosensitivity of OS cells through exosome-transmitted miR-384. (A) qRT-PCR analysis of extracellular miR-384 of MG63 cells treated with RNase A (10 μg/ml) or the combination of RNase A and 0.3% Triton X-100. *P < 0.05 compared with RNase A group. (B) Left: Representative transmission electron microscopy images of cup-shaped exosomes released by MG63 cells. Scale bar = 500 nm and 100 nm, respectively. Right: Nanoparticle tracking analysis on the size distribution and relative concentration of exosomes derived from MG63 cells using the Nano-sight software. (C) Western blotting of exosomal protein markers (CD63 and CD81) from purified exosomes and cell extracts. (D) qRT-PCR detection of miR-384 expression in exosomes derived from MG63 cells treated with DMSO or luteolin. (E) Representative fluorescence microscopy images showing cellular uptake of exosomes (PKH67-labeled, red) into recipient MG63/DOX cells (DAPI-labelled, blue). (F) Effect of specified exosomes on the expression of miR-384 and PTN in recipient MG63/DOX cells. Exosomes were derived from MG63 cells treated with or without luteolin and then incubated with MG63/DOX cells. (G) Effect of specified exosomes on the chemoresistance of recipient MG63/DOX cells by cell viability analysis. MG63/DOX cells co-cultured with exosomes from MG63 cells were treated with a series of concentrations of doxorubicin for 48 h and cell growth was assessed by CCK-8 assay. (H) Schematic diagram of the co-culture system. MG63 cells transfected with miR-NC or miR-384 mimic plasmids were seeded in the upper chamber and co-incubated with MG63/DOX cells placed in the lower chamber in a co-culture system with a 0.4 µM pore membrane. Then the MG63 cells were treated with the nSMase inhibitor GW4869 or control DMSO. (I) MG63 cells transfected with miR-384 mimics could increase the miR-384 level and downregulate the PTN level in MG63/DOX cells in a co-culture system and this effect could be significantly attenuated by 10 µM GW4869. (J) CCK-8 assay was used to assess the chemoresistance of MG63/DOX cells after co-culturing with miR-384 mimic-transfected MG63 cells with or without GW4869 treatment. DAPI, 4′,6-diamidino-2-phenylindole; Exo, exosome; Lut, luteolin; ctr: control. (For interpretation of the references to colour in this figure legend, the reader is referred to the web version of this article.)