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Programmable DNA materials hold great potential in biochemical and biomedical researches, yet the complicated synthesis, and the low stability and targeting efficacy in complex biological milieu limit their clinical translations. Here we show a one‐pot assembly of DNA‐protein superstructures as drug vehicles with specifically high affinity and stability for targeted therapy. This is achieved by biomimetic assembly of programmable polymer DNA wire into densely packed DNA nanosphere with an alkaline protein, protamine. Multivalent DNA nanostructures encoded with different types and densities of aptamers exhibit high affinity to targeted cells through polyvalent interaction. Our results show high cancer cell selectivity, reduced side effect, excellent therapeutic efficacy, and sensitive tumor imaging in both subcutaneous and orthotopic non‐small‐cell lung cancer murine models. This biomimetic assembly approach provides practical DNA nanomaterials for further clinical trials and may advance oligonucleotide drug delivery. [ABSTRACT FROM AUTHOR]

DNAzyme‐based gene therapy holds immense prospects for effectively treating severe diseases, yet is constrained with inefficient delivery and unconditional activation. Herein, we designed a bioinspired self‐catabolic DNA nanocapsule for sustaining tumor‐specific cascade activation of therapeutic DNAzyme. The exquisite DNAzyme was temporarily masked by the self‐excising DNAzyme in the hierarchical rolling circle replication (RCR) nanostructures, thus stayed in an inactive state in physiological fluids. Through the multivalent tumor‐anchoring aptamer strands, the RCR nanocapsule was specifically accumulated in cancer cells and was sequentially activated for motivating the ultimate DNAzyme‐mediated gene silencing via the intelligent stimuli‐responsive cascade DNAzyme activation. By virtue of the programmable RCR assembly strategy, our compact DNAzyme nanoplatform shows great promise for developing versatile smart gene therapeutics and personalized nanomedicines. [ABSTRACT FROM AUTHOR]

DNA nanostructures have recently attracted increasing interest in biological and biomedical applications by virtue of their unique properties, such as structural programmability, multi‐functionality, stimuli‐responsive behaviors, and excellent biocompatibility. In particular, the intelligent responsiveness of smart DNA nanostructures to specific stimuli has facilitated their extensive development in the field of high‐performance biosensing and controllable drug delivery. This minireview begins with different self‐assembly strategies for the construction of various DNA nanostructures, followed by the introduction of a variety of stimuli‐responsive functional DNA nanostructures for assembling metastable soft materials and for facilitating amplified biosensing. The recent achievements of smart DNA nanostructures for controllable drug delivery are highlighted. Finally, the current challenges and possible developments of this promising research are discussed in the fields of intelligent nanomedicine. [ABSTRACT FROM AUTHOR]

DNAzymes have been recognized as potent therapeutic agents for gene therapy, while their inefficient intracellular delivery and insufficient cofactor supply precludes their practical biological applications. Metal–organic frameworks (MOFs) have emerged as promising drug carriers without in‐depth consideration of their disassembled ingredients. Herein, we report a self‐sufficient MOF‐based chlorin e6‐modified DNAzyme (Ce6‐DNAzyme) therapeutic nanosystem for combined gene therapy and photodynamic therapy (PDT). The ZIF‐8 nanoparticles (NPs) could efficiently deliver the therapeutic DNAzyme without degradation into cancer cells. The pH‐responsive ZIF‐8 NPs disassemble with the concomitant release of the guest DNAzyme payloads and the host Zn2+ ions that serve, respectively, as messenger RNA‐targeting agent and required DNAzyme cofactors for activating gene therapy. The auxiliary photosensitizer Ce6 could produce reactive oxygen species (ROS) and provide a fluorescence signal for the imaging‐guided gene therapy/PDT. [ABSTRACT FROM AUTHOR]

DNA, drug delivery, nanostructures, self-assembly, stimuli-responsive Keywords: DNA; drug delivery; nanostructures; self-assembly; stimuli-responsive EN DNA drug delivery nanostructures self-assembly stimuli-responsive 1 1 1 02/26/21 20210224 NES 210224 B Intelligent stimuli-responsive DNA b nanostructures have attracted increasing attention for biological and biomedical research owing to their promising native biocompatibility, programmability, multifunctionality, responsiveness to biological cues, and easy implementation for designing new materials. Frontispiece: Construction of Smart Stimuli-Responsive DNA Nanostructures for Biomedical Applications. [Extracted from the article]

An on-site activatable gene theranostic platform is constructed with DNA prodrug-laden metallo-nanoassemblies. Under microenvironment stimuli, the inactive DNAs are sensitively transformed into active DNAzymes via chain reaction, and the metallo-nanoassembly allows self-sufficient enzymatic cofactors and accelerated RNA-cleavage activity of the DNAzymes. Such amplified orthogonal activation of gene theranostics may offer new way for precision nanomedicine. [Display omitted] • A programmable and responsive nanoplatform for tumor-specific gene theranostics. • High-performance metallo-nanoassemblies as effective oligonucleotide drug vehicles. • Multiple biomarkers-triggered signal amplification and dual-mode imaging. • On-site DNAzyme activation and self-boosted gene silencing for precise and robust cancer therapy. • Such amplified orthogonal activation of gene regulation approach benefits precision nanomedicine. RNA-cleaving DNAzymes hold great promise for gene regulation, yet the low in vivo catalytic efficacy and the unavoidable nonspecific response in normal tissues hinder their practical applications. Herein, we develop a DNA prodrug-laden metallo-nanoassembly for sensitive orthogonal activation of DNAzymes to regulate disease gene with high precision and efficacy. With rich positive charges, metallo-nanoassemblies efficiently load DNA prodrugs (functional DNAzyme subunits), and thus improve drug stability and cellular uptake efficacy. Under tumor microenvironment, the cancer-specific biomarker triggers the amplified assembly of DNA prodrugs into active DNAzymes to efficiently cleave tumor-involved mRNA. Meanwhile, these glutathione-responsive metallo-nanoassemblies decompose and release metal ions as self-sufficient DNAzyme cofactors, which are accommodated into the afore-assembled DNAzymes to enhance the gene cleavage activity. Moreover, upon laser stimulus, these photothermal metallo-nanoassemblies can also remarkably promote the catalytic reaction of DNAzymes via the elevated local temperature. Such a smart delivery approach allows disease diagnosis via sensitive fluorescence and photothermal imaging, and achieves the precise and robust gene regulation with photothermal ablation as an auxiliary therapy. These results provide a new route to design programmable and activatable prodrugs for precision nanomedicine. [ABSTRACT FROM AUTHOR]

Extracellular vesicles (EVs) have been emerged as versatile drug delivery vehicles due to their outstanding biocompatibility and long-term circulation, yet are constrained with low targeting property and inefficient loading capacity from post-synthetic passive EVs encapsulation. Herein, we report a simple and feasible in situ biosynthetic approach to encapsulate tumor-targeting folate (FA)-modified EVs with intracellularly produced protoporphyrin X (PpIX) and doxorubicin (DOX). As compared with the traditional directly drug-incubated or drug-electroporated EVs, these biosynthesized EVs revealed high drug-loading efficiency with minimized structural and functional perturbations. Our multifunctional EVs revealed the enhanced accumulation and penetration into deep tumor parenchyma, as well as the strengthened immune response to ablate orthotopic and metastatic tumors, thus realizing the more reliable photochemotherapy. As an intelligent multi-mode therapeutic system, our biosynthetic EVs could be engineered with more therapeutic agents and show great promise for biomedicine applications. [ABSTRACT FROM AUTHOR]