Expression of let-7 and miR-200 families. Total microRNA was extracted using the Ambion mirVana PARIS Kit (Invitrogen). Real-time PCR was performed with miScript SYBR Green Kit to compare let-7 and miR-200 family expression between ovarian cancer cell lines (OVAR-3 and SKOV-3 cells) (A) and between cell-derived exosomes (exo-OVAR-3 and exo-SKOV-3) (B). Data are represented as mean ± SEM (n = 6). In A and B, ANOVA p < 0.0001 between groups. In B, *p < 0.001 vs exo-SKOV-3.