Fig. 4

MSCpos-EV treatment increases epithelial bronchial cell proliferation. A) Bar plots showing the viability rate of HBEC-KRAS^V12high cells after MSCpos- and MSCneg-EV treatment, as assessed by a RealTime-Glo assay (n = 5). B) Analysis of the ability of HBEC-KRAS^V12high cells to grow in 3D culture using VitroGel. The graph shows the number of colonies formed after 2 weeks by cells treated with MSCpos- and MSCneg-EVs (n = 5). C) Quantification of the c-Myc content in MSCpos- and MSC-neg-EVs (n = 5). D) Histograms showing the intracellular c-Myc content (left), miR-92a levels (center) and TGFBRI (right) in HBEC-KRAS^V12high cells after MSCpos- and MSCneg-EV treatment (n = 4). E) Proliferation analysis of HBEC-KRAS^V12high cells treated with MSCneg-EVs overexpressing c-Myc (n = 4). F) Representative images and bar graphs showing the ability of HBEC-KRAS^V12high cells treated with MSCneg-EVs + c-Myc to grow in 3D culture compared to that of cells treated with MSCneg-EVs (number of colonies)(n = 3). G) Analysis of VEGF-A levels (pg/ml) in CM collected from HUVECs and macrophages after 48 h of treatment with MSCpos- and MSCneg-EVs. H) Graphs showing the proliferation of HBEC-KRAS^V12high cells treated with CM from HUVECs (left panel) and macrophages (right panel) (n = 5). Untreated (NT) cells were used as a control. *** p < 0.0001, *p < 0.05 versus controls. Data are expressed as the mean ± S.E.M. values