Toward in vivo Targeting Delivery of siRNA for Efficient Cancer Therapy

The main obstacle in siRNA therapy is RNA delivery to the cytoplasm, where it can guide sequence-specific mRNA degradation. Attempts to develop effective nonviral vectors for in vivo delivery of nucleic acids through a systemic route are hampered by difficulties of combining high extracellular stability with ready availability of the nucleic acids following entry into cells. Other challenges with non-viral gene delivery include limitations in targetcell specificity. Here we report a targeted siRNA delivery vector that displays good extracellular stability and intracellular bioavailability to permit efficient gene silencing.