Exosomal miR-34b suppresses cell proliferation and EMT in ovarian cancer cells. (A) Relative expression levels of miR-34b in SKOV3 cells co-cultured with SKOV3 or IOSE-80. (B) Cell viability assays and (C) cell invasion assays in SKOV3 cells cultured with exosomes isolated from SKOV3, IOSE-80, IOSE-80+NC or IOSE-80+anti-miR-34b. (D) Relative expression levels of EMT markers (E-cadherin, N-cadherin and Snail) in SKOV3 cells co-cultured with SKOV3, IOSE-80, IOSE-80+NC or IOSE-80+anti-miR-34b. (E) and (F) Western blotting analysis of EMT markers (E-cadherin, N-cadherin, and Snail) (20,21) in SKOV3 cells co-cultured with SKOV3, IOSE-80, IOSE-80+NC or IOSE-80+anti-miR-34b. **P<0.01 vs. SKOV3. $P<0.05, $$P<0.01 and $$$P<0.001 vs. SK-Exos, #P<0.05, ##P<0.01 vs. NC-Exos. EMT, epithelial-mesenchymal transition; NC, negative control; miR, microRNA; SK, SKOV3; IO, IOSE-80; Exos, exosomes.