Doxorubicin-derived extracellular vesicles regulate IL-1β and IL-6 expression. IL-1β and IL-6 gene (A) and protein (B) expression after EV treatment. Human osteosarcoma cells were treated with 50 µg/mL of EVs and analyzed for IL-1β and IL-6 gene and protein expression by qRT-PCR and ELISA, respectively. The data represent the means ± SD. *, p < 0.05 and **, p < 0.01 vs. control. (C) PD-L1 gene expression after EV treatment. Osteosarcoma cells were treated with 100 µg/mL of EV in the presence or absence of IL-1RA (100 ng/mL) for 24 h, and qRT-PCR was performed to determine PD-L1 gene expression. The data represent the means ± SD. **, p < 0.01 vs. control.