Self-Assembled Polymeric Nanomicelles as Delivery Carriers for Antitumor Drug Camptothecin

Despite being highly recognized as an antitumor candidate due to its high potency in binding to DNA topoisomerase I and inhibiting of DNA relegation, full clinical application of camptothecin is unfortunately hampered by its poor solubility in aqueous medium and by the adverse effects caused by its hydrolyzed product under physiological conditions. In an attempt to increase its effective solubility, nanomicelles formed through self-assembly of copolymers by polymer-drug conjugate or by physical envelopment have recently been established to improve the efficacy of many drugs. This review provides the most up-to-date information available relating novel nanomicelles technology to the improvement and realization of the full potential of camptothecin. In particular, physicochemical and biological properties of camptothecin and its derivatives, the controlled factors of micelle formation, the techniques of drug encapsulation, and the structure-properties of nanomicelles are elucidated and discussed. Undoubtedly, polymer nanomicelle carriers can be selectively delivered to tumors via the enhanced permeability and retention effect. Moreover, micelles with smart functions such as stimulus-responsive and specific drug targeting may enhance the activity of potent bioactive compounds, facilitating their clinical applications.