Polymeric nanocarriers for cancer treatment: the promise of sensitive poly(2-(diisopropylamino)ethyl methacrylate)

Abstract

Polymeric nanoparticles are extremely valuable carriers for drug/gene delivery to treat cancer, as they can protect different therapeutic agents during blood circulation while being able to deliver them at desired locations. Owing to the versatility of polymers, it is possible to fine-tune the performance of nanocarriers by changing different properties, such as chemical structure, architecture, composition and molecular weight or even by functionalising the polymers with targeting molecules. The use of pH-sensitive polymers is a very popular strategy to prepare smart carriers, taking advantage of the acidic intratumoural environment to induce hydrophobic/hydrophilic transitions that allow fast and efficient release of small drugs or genetic material. This review summarizes the contributions of the use of promising pH-sensitive poly(2-(diisopropylamino)ethyl methacrylate) (PDPA), with pK_a around 6.2, in the preparation of nanocarriers for the treatment of different types of cancer through gene therapy, drug delivery or photodynamic therapy. Interest in PDPA-based copolymers for biomedical applications is increasing, as different studies have reported successful encapsulation and delivery of different therapeutic molecules with PDPA-based smart nanocarriers. In vivo studies have shown that tumour growth can be suppressed, revealing the potential of new cancer therapies.