Abstract
RNA interference(RNAi) is expected to be a novel therapeutic method for various diseases including cancer, AIDS and viral hepatitis. RNAi-based therapy could be realized by the development of efficient delivery system for small interfering RNA(siRNA), the effector molecule in RNAi. Because various methods are available to deliver siRNA into the cytoplasm of cultured cells, such as viruses, transfection reagents, and electroporation, RNAi-based knock down is becoming a standard to identify the function of the gene of interest. However, the application of siRNA or siRNA-expressing vector to in vivo gene silencing for the treatment of diseases has encountered with barriers on the delivery. To overcome these problems, the development of delivery system is highly required. Delivery methods that have been developed for in vivo delivery of antisense oligonucleotides and genes can be applied to siRNA or siRNA-expressing vectors, Recently, we have shown that siRNA and siRNA-expressing plasmid DNA efficiently delivered to the liver can significantly suppress target genes. In this review, we summarize the possibility of in vivo RNAi by delivering siRNA or siRNA-expressing vectors in mice.
