Cancer immunotherapy has transformed oncological treatment by harnessing the immune system to target tumors. However, challenges such as drug resistance, poor immunogenicity, and inefficient antigen delivery limit its full potential. DNA nanotechnology offers a transformative solution through the development of programmable, biocompatible nanostructures capable of precise antigen presentation, codelivery of immunostimulatory agents, and modulation of the tumor microenvironment. DNA nanostructures, including origami, tetrahedra, and virus-like particles, enable multivalent display of tumor antigens, incorporation of adjuvants like CpG oligodeoxynucleotides, and encapsulation of therapeutic RNAs such as mRNA and siRNA. These features enhance antigen presentation, improve endosomal escape, and stimulate robust innate and adaptive immune responses. Moreover, bispecific DNA nanoconstructs can bridge immune effector cells with tumor cells, simulating immune synapses and enhancing cytotoxicity. The modularity and precision of DNA scaffolds also support patient-specific vaccine development, particularly when integrated with genomic sequencing and CRISPR-based neoantigen discovery. Virus-inspired DNA nanostructures further mimic native viral immunogenicity while allowing safer, customizable antigen loading. Future efforts should focus on overcoming translational barriers, including scalable manufacturing, in vivo stability, and regulatory standardization. With continued advances in structural design, ligand functionalization, and immune engineering, DNA nanotechnology holds the potential to reshape cancer immunotherapy. It paves the way for highly targeted, personalized, and effective treatments that outperform current clinical approaches in specificity, efficacy, and safety.
DNA nanostructures can be tailored to perform a wide variety of functions, with continued interest in biological applications. Some aspects of DNA nanostructure assembly can hinder the ability of nanostructures to be useful in physiological environments. Typical assembly methods employ magnesium ions to stabilize the structure, which leave the structure susceptible to damage by nucleases in body fluids. Further, DNA nanostructure assembly typically involves a thermal annealing protocol in which DNA strands are heated in a specific buffer to a high temperature and cooled slowly at specific rates, preventing convenient encapsulation of temperature-sensitive guest molecules. In this work, we demonstrate the assembly of a wide variety of DNA nanostructures and 3D crystals in a hydrated ionic liquid (choline dihydrogen phosphate, CDHP) instead of magnesium at constant moderate temperatures, thus avoiding thermal annealing. CDHP-assembled structures show enhanced biostability against a variety of nucleases. Molecular dynamics simulations show that choline ions stabilize DNA nanostructures by a direct and close-range interaction in contrast to the predominantly water-mediated interactions of Mg2+, leading to enhanced nuclease resistance in CDHP-containing environments. CDHP-assembled structures do not affect the viability of HepG2 cells and show higher cell internalization. Overall, this work develops a potential method to construct more biostable DNA nanostructures and 3D crystals in a simple one-tube process. Assembly of DNA nanostructures under isothermal conditions is desirable for scaffolding biomolecules and to reduce the need for thermal annealing instruments, allowing nanostructure preparation in low-resource settings.
