Fig. 6

Antitumor effects of conNK-sEV and mNK-sEV. A CCK-8 assays for the cytotoxicity of conNK-sEV and mNK-sEV (100 µg/mL) on MGC803 cells at 24 h (n = 3). B Representative flow cytometry dot plot for apoptosis in MGC803 cells treated with conNK-sEV and mNK-sEV (100 µg/mL) for 24 h, respectively. C The percentage of apoptotic cells in MGC803 cells were analyzed by flow cytometry (n = 3). D Schematic design for sEV treatment in subcutaneous MGC803 cells xenografted tumor model in BALB/c nude mice. i.v., intravenous; s.c., subcutaneous. E Representative images of subcutaneous xenograft tumors established by MGC803 cells in BALB/c nude mice (n = 5) that were treated by PBS, conNK-sEV and mNK-sEV, respectively. F Weights of the harvested tumors. G Tumor growth curves subject to different treatments. H, I Representative image of Ki-67 staining of tumors (scale bar = 100 µm). J, K TUNEL staining of tumors (scale bar = 100 µm). L The body weights of mice during in vivo efficacy study were measured every 3 days. Data are shown as mean ± SD. M Histological images of major organs (scale bar = 100 µm). N Weight indices of major organ, including kidneys, livers, brains, lungs, and hearts, calculated as organ weight (mg) per gram (g) of mouse body weight. *p < 0.05, **p < 0.01, ***p < 0.001, ****p < 0.0001