From stealthy polymersomes and filomicelles to "self" Peptide-nanoparticles for cancer therapy.

Polymersome vesicles and wormlike filomicelles self-assembled with amphiphilic, degradable block copolymers have recently shown promise in application to cancer therapy. In the case of filomicelles, dense, hydrophilic brushes of poly(ethylene glycol) on these nanoparticles combine with flexibility to nonspecifically delay clearance by phagocytes in vivo, which has motivated the development of "self" peptides that inhibit nanoparticle clearance through specific interactions. Delayed clearance, as well as robustness of polymer assemblies, opens the dosage window for delivery of increased drug loads in the polymer assemblies and increased tumor accumulation of drug(s). Antibody-targeting and combination therapies, such as with radiotherapy, are emerging in preclinical animal models of cancer. Such efforts are expected to combine with further advances in polymer composition, structure, and protein/peptide functionalization to further enhance transport through the circulation and permeation into disease sites.