Fig. 1

Ovarian cancer-secreted EVs induce the MMT process in mesothelial cells. a Representative transmission electron microscopy images of EVs purified from cell supernatant. Scale bar, 200 nm. b Size distribution of EVs measured by ZETASIZER Nano. c Western blot analysis of HSP70, CD9, CD63, CD81, GAPDH, Calnexin and GM130 in cell lysate and the EV fraction. d PKH67-labeled IOSE-80 EVs, SKOV3 EVs and A2780 EVs (green) were incubated with MeT-5A cells for 24 h and observed by confocal microscopy after staining of the F-actin filaments (red) and nuclei (blue), PBS treatment was used as non-EV control. Scale bar, 20 μm. e MeT-5A cells were co-cultured with EVs from two cancer cells and IOSE-80 cells. The PBS and TGF-β1 (0.5 ng/ml) plus IL-1β (2.5 ng/ml) groups were used as blank and positive control, respectively. The morphology alteration was observed using a phase contrast microscope. Scale bar, 100 μm. f MMT-related proteins of MeT-5A cells with different treatments were detected by western blot, GAPDH was used as the loading control. g E-Cadherin and N-Cadherin proteins (green) of MeT-5A cells with different treatments were observed by Immunofluorescence assay. Scale bar, 20 μm. h Migration assay was performed to evaluate the migratory ability of MeT-5A cells under different conditions. Representative images were shown and migrated cells were counted. Scale bar, 100 μm. i Representative images of CMTPX-labelled SKOV3 (red) and A2780 (red) cells adhesion to MeT-5A cells (blue) were shown and adhered cells were calculated. Scale bar, 100 μm. Data are representative of at least three independent experiments and are presented as mean ± SD. *p < 0.05, **p < 0.01, ***p < 0.001