Development of Antibody-Oligonucleotide Complexes for Targeting Exosomal MicroRNA

MicroRNAs in exosomes (exosomal miRNAs) are considered as significant targets for cancer therapy. Anti-miR oligonucleotides are often used for the functional inhibition of miRNAs; however, there are no studies regarding the regulation of exosomal miRNA functions. In this study, researchers from Nagasaki University attempted to develop a novel drug delivery system using anti-exosome antibody–anti-miR oligonucleotide complexes (ExomiR-Tracker) to hijack exosomes to carry anti-miR oligonucleotides inside exosome-recipient cells. They found that ExomiR-Tracker bound to the exosomes, and then the complexes were introduced into the recipient cells. They also found that anti-miR oligonucleotides introduced into the recipient cells can exhibit inhibitory effects on exosomal miRNA functions in vitro and in vivo. The researchers believe that this strategy would be a promising one for targeting exosomal miRNAs.