Pure DNA scaffolded drug delivery systems for cancer therapy.

The development of effective drug delivery system is highly important for targeted tumor therapy. Over the past few decades, a number of biomaterials have been extensively explored as potential drug loading vehicles. Among them, DNA has emerged as a highly promising scaffold to construct drug delivery systems, owing to its excellent biocompatibility, precise programmability, multifunctionalities, structural predictability, and versatile modifications for improved biostability. Herein, the drug delivery systems that purely comprise of DNA are reviewed. Drugs can be incorporated into DNA via distinct mechanisms, and various DNA architectures have been developed to load different types of anti-tumor therapeutics. For therapeutic applications, we focus on their intracellular delivery and drug release, and DNA-based platforms with different cellular uptake pathways and stimuli-responsive drug release profiles are discussed. Finally, there search opportunities of the field are speculated to pave the way for future research direction.