Ultrasound‑targeted microbubble destruction‑mediated miR‑205 enhances cisplatin cytotoxicity in prostate cancer cells.

MicroRNAs (miRNAs) are non‑coding ~20 nucleotides long sequences that function in the initiation and development of a number of cancers. Ultrasound‑targeted microbubble destruction (UTMD) is an effective method for microRNA delivery. The aim of the present study was to investigate the potential roles of UTMD‑mediated miRNA (miR)‑205 delivery in the development of prostate cancer (PCa). In the present study, miR‑205 expression was examined by reverse transcription‑quantitative polymerase chain reaction assay. miR‑205 mimics were transfected into PC‑3 cells using the UTMD method, and the PC‑3 cells were also treated with cisplatin. Cell proliferation, apoptosis, migration and invasion abilities were detected using Cell Counting kit‑8, flow cytometry, wound healing and Transwell assays, respectively. In addition, the protein expression levels of caspase‑9, cleaved‑caspase 9, cytochrome c (cytoc), epithelial (E)‑cadherin, matrix metalloproteinase‑9 (MMP‑9), phosphorylated (p)‑extracellular signal‑regulated kinase (ERK) and ERK were measured by western blot analysis. The results of the present study demonstrated that miR‑205 expression was low in human PCa cell lines compared with healthy cells and that UTMD‑mediated miR‑205 delivery inhibited PCa cell proliferation, migration and invasion, and promoted apoptosis modulated by cisplatin compared with UTMD‑mediated miR‑negative control group and miR‑205‑treated group. Furthermore, it was demonstrated that UTMD‑mediated miR‑205 transfection increased the expression of caspase‑9, cleaved‑caspase 9, cytochrome c and E‑cadherin, and decreased the expression of MMP‑9 and p‑ERK. Therefore, UTMD‑mediated miR‑205 delivery may be a promising method for the treatment of PCa.