Background: Polymeric micelles can provide a valid way for cancer treatment with several benefits
including high water-solubility of lipophilic drugs, low unwanted effects of cytotoxic drugs by way of reduced
systemic exposure and prolonged retention time in the circulatory system.
Objective: Recently, there is an increasing interest in preparing poly (ethylene glycol)-poly (amino acid)
copolymeric micelles as drug delivery carriers due to their multifunctional property, easy decoration and biosafety.
The copolymer contains several functional groups, which show stronger interactions with drugs or can be
transferred to develop different types of the copolymers showing pH-, reduction-, thermo-sensitive, targeted or
double-function properties. In addition, conjugation of drugs with these copolymers also becomes a novel
modification method with the aim of higher drug loading capacity and stability. Copolymeric micelles show
exciting advantages on improving a drug’s water-solubility, release behavior, in vitro activity, targeted delivery
pharmacokinetic property and biodistribution. In this review, we will introduce the recent development of
poly(ethylene glycol)-modified poly (amino acid) copolymeric micelles as anticancer drug delivery systems
containing different stimuli (such as thermo-, pH-, reduction- or special enzyme- condition) functional groups and
targeting ligands to improve cellular uptake or biostablility of drug-loaded micelles.
Conclusion: Poly (ethylene glycol)-poly (amino acid) copolymeric micelles provide an opportunity to realize
anticancer drug delivery with environment-responsive and/or targeting property.