Current Trends in the Use of Cationic Polymer Assemblies for siRNA and Plasmid DNA Delivery

Gene therapy is a promising approach for disease prevention and therapy. Efficient gene delivery is an important factor limiting gene delivery. Due to the poor stability of nucleotide molecules in vivo, they require an association with delivery systems to overcome extracellular and intracellular barriers and allow access to the site of action. In this review, we discuss the challenges currently encountered in the delivery of DNA and RNAi-based therapies using the most common cationic polymer assemblies including polylysines, chitosan, polyethylenimines, dendrimers, cyclodextrins and illustrate with examples how chemical modification of cationic assemblies may contribute to their successful application in the clinic.