Peptide-based nanostructures for cancer diagnosis and therapy.

Peptide-based nanoparticles (pep-NPs) are emerging as promising imaging and therapeutic agents against cancer due to their biocompatibility and tunability. Optimized design of the peptide sequence and moderate conjugation of the sequence with extraneous molecules are crucial to the performance of the inherent properties of pep-NPs such as nanostructure formation and ability of drug delivery. Meanwhile, the peptide sequences based on natural/unnatural amino acids could be utilized for designing nanostructures susceptive/resistant to specific enzymes. Herein, we firstly summarize the basic peptide structures to provide a whole image of pep-NPs. Subsequently, the diagnostic strategies based on different imaging modalities and recent therapeutic applications of pep-NPs for cancer are reviewed.