Bone mesenchymal stem cell‑derived exosome‑encapsulated microRNA‑125b‑5p inhibits ovarian cancer progression via DDX5 downregulation

Exosomes can be used to mediate the delivery of nucleic acids such as microRNA-125b-5p (miR-125b-5p), a tumor-suppressor in certain types of cancer, into tumor cells. The present study investigated the use of bone mesenchymal stem cells-derived exosome (BMSCs-Exo) delivery of miR-125b-5p in ovarian cancer (OC). BMSCs were transfected with miR-125b-5p mimic, from which exosomes termed Exo-miR-125b-5p mimic were extracted. The expression levels of miR-125b-5p in OC tissue samples, BMSCs, exosomes and SKOV3 cells were quantified using reverse transcription-quantitative PCR. The influence of Exo-miR-125b-5p mimic on the biological functions of OC was evaluated through cell proliferation, invasion, migration and apoptosis assays. The targeting relationship between miR-125b-5p and DEAD-box helicase 5 (DDX5) was verified, and the expression levels of DDX5 in OC samples and SKOV3 cells were quantified using western blotting. miR-125b-5p was downregulated in tumor tissue samples from patients with OC. BMSCs-Exo reduced the malignant properties of SKOV3 cells <i>in vitro</i>, and these effects were be advanced by miR-125b-5p upregulation. miR-125b-5p targeted and inhibited DDX5 expression. DDX5 overexpression inhibited Exo-miR-125b-5p-induced suppression of OC development. Overall, this study highlights that BMSCs-Exo-encapsulated miR-125b-5p inhibited OC progression via DDX5 downregulation, providing insight into the molecular mechanisms underlying OC.