Polymer assemblies: Intelligent block copolymer micelles for the programmed delivery of drugs and genes

Since the advent of new concepts for the exploiting of polymer conjugates as drug carriers in the 1970s, polymer science has played a pivotal role in both the design of novel drug carriers for cancer treatment and the enhancement of the efficacy and bioavailability of existing drugs (1-2). The major advantage of these polymer-based carriers is the easy modification (depending on the purpose at hand) of their structural and functional features, an advantage that may overcome the limits of natural carriers, like safety and production costs, by providing the appropriate properties for therapeutics to mass producible polymers and their assemblies (3). For this reason, interest has recently centered on the improved functionalities and the chemical structures of polymer assemblies, advances in which have led to new types of cancer chemotherapy; moreover, the requirements for the development of carriers whose properties are optimized for anticancer drugs, diagnostic agents, and genes are growing day by day. In this chapter, we will take a look at the recent studies that concern this issue and that advance suggestions for future design, development, and clinical applications of polymer assemblies in the delivery of drugs and genes, particularly focusing on one of the unique carriers, the polymeric micelle, that our research group has been investigating for the past decade.