The nanoscale spatial organization of transmembrane tumor necrosis factor (TNF) receptors has been implicated in the regulation of cellular fate. Accordingly, molecular tools that can induce specific arrangements of these receptors on cell surfaces would give us an opportunity to study these effects in detail. To achieve this, we introduce DNA origami nanostructures that precisely scaffold the patterning of TNF-related apoptosis-inducing ligand-mimicking peptides at nanoscale level. Stimulating human breast cancer cells with these patterns, we find that around 5 nm is the critical interligand distance of hexagonally patterned peptides to induce death receptor clustering and a resulting apoptosis. We thus offer a strategy to reverse the non-efficacy of current ligand- and antibody-based methods for TNF superfamily activation.
DNA origami holds great potential for advancing therapeutics, but the lack of methods for the precise assessment of structural integrity in vivo prevents its translation. Here we introduce proximity ligation assay for structural tracking and integrity quantification (PLASTIQ) for resolving origami structural integrity with only 1 µl of blood sample and with a detection limit of 0.01 fM. Through PLASTIQ, we could observe and quantify the dynamics of DNA origami degradation during blood circulation and evaluate the effectiveness of PEGylation for slowing this process in a murine model. Additionally, by using a double-layered barrel-like origami structure, we found distinct degradation kinetics of DNA helices depending on their specific location, revealing the slower degradation of internal helices compared with the outer ones. Our results suggest that PLASTIQ offers a quantitative approach for assessing DNA origami integrity in vivo by longitudinal sampling, providing dynamic pharmaceutical-level insights for accelerating the development of DNA-nanostructure-based therapeutic molecules and drugs.
The DNA origami method has revolutionized the field of DNA nanotechnology since its introduction. These nanostructures, with their customizable shape and size, addressability, nontoxicity, and capacity to carry bioactive molecules, are promising vehicles for therapeutic delivery. Different approaches have been developed for manipulating and folding DNA origami, resulting in compact lattice-based and wireframe designs. Platinum-based complexes, such as cisplatin and phenanthriplatin, have gained attention for their potential in cancer and antiviral treatments. Phenanthriplatin, in particular, has shown significant antitumor properties by binding to DNA at a single site and inhibiting transcription. The present work aims to study wireframe DNA origami nanostructures as possible carriers for platinum compounds in cancer therapy, employing both cisplatin and phenanthriplatin as model compounds. This research explores the assembly, platinum loading capacity, stability, and modulation of cytotoxicity in cancer cell lines. The findings indicate that nanomolar quantities of the ball-like origami nanostructure, obtained in the presence of phenanthriplatin and therefore loaded with that specific drug, reduced cell viability in MCF-7 (cisplatin-resistant breast adenocarcinoma cell line) to 33%, while being ineffective on the other tested cancer cell lines. The overall results provide valuable insights into using wireframe DNA origami as a highly stable possible carrier of Pt species for very long time-release purposes.
Over 40% of human cancers harbor extrachromosomal DNA (ecDNA), which correlates with therapy resistance and poor prognosis. Yet research is limited by a lack of robust de novo ecDNA models. We present a CRISPR-Cas9 based approach for generation of ecDNA in cell lines and mouse liver. In HEK293 cells, CRISPR-induced MYC-bearing ecDNA ([MYCcircle]) promoted cancer hallmarks, including enhanced proliferation, increased migration, and reduced apoptosis. To model ecDNA in mice, we combined Cas9 knock in mice with lipid-nanoparticle delivery of sgRNAs in the liver targeting the Myc–Pvt1 locus. When combined with Trp53 or Pten loss, the resultant [Myccircle] caused hepatocellular carcinomas with amplified levels of [Myccircle] and elevated, heterogenous Myc expression, supporting evidence of ecDNA involvement in tumorigenesis. Our approach offers a fast and versatile tool, where target-sequence flexibility allows rapid generation of animal and cell models with any investigator-specified ecDNA, thereby enabling study of the direct role of ecDNA in cancer progression.
DNA origami is becoming an attractive platform for data storage, yet current approaches rely on the limited stability of DNA hybridization, preventing them from fully utilizing the stability and cost-effective copying inherent to classical sequence-based storage. Here we introduce DNA Origami for Combinatorial data Storage (DOCS), where we encode information into the scaffold molecule using a combinatorial enzymatic approach. This enables text encoding that is biologically cloneable, stable at high temperatures, and randomly accessible. We further demonstrate the DOCS platform’s combinatorial power by creating a stochastic molecular authentication system. Finally, we show using simulations that expanding the information capacity of data carriers allows for the storage and recovery of large files up to several hundred kilobytes in size. DOCS provides a robust, scalable strategy for molecular data storage and security that bridges the gap between classical DNA data storage strategies and DNA nanostructure-based methods.