Temperature-responsive polymeric micelles for optimizing drug targeting to solid tumors

Targeting to solid tumors is the most challenging issue in the drug delivery field. To obtain the ideal pharmacodynamics of administrated drugs, drug carriers must suppress drug release and interactions with non-target tissues while circulating in the bloodstream, yet actively release the incorporated drug and interact with target cells after delivery to the tumor tissue. To handle this situation, stimuli-responsive drug carriers are extremely useful, because carriers change their physicochemical properties to control the drug release rate and interaction with cells in response to the surrounding environmental conditions or applied physical signals. The current review focuses on the strategy and availability of temperature-responsive (TR) polymeric micelles as a next-generation drug carrier. In particular, we discuss the unique properties of TR polymeric micelles, such as temperature-triggered drug release and intracellular uptake system. In addition, we explore the methodology for integrating other targeting systems into TR micelles to pursue the ideal pharmacodynamics in conjunction with thermal therapy as a future prospective of the TR system. (C) 2014 Elsevier B.V. All rights reserved.