Branched Antisense and siRNA Co-Assembled Nanoplatform for Combined Gene Silencing and Tumor Therapy

RNase H-sensitive multifunctional ASO-based constructs as promising tools for the treatment of multifactorial complex pathologies

Combined therapies play a key role in the fight against complex pathologies, such as cancer and related drug-resistance issues. This is particularly relevant in targeted therapies where inhibition of the drug target can be overcome by cross-activating complementary pathways. Unfortunately, the drug combinations approved to date -mostly based on small molecules- face several problems such as toxicity effects, which limit their clinical use. To address these issues, we have designed a new class of RNase H-sensitive construct (3ASO) that can be disassembled intracellularly upon cell entry, leading to the simultaneous release of three different therapeutic oligonucleotides (ONs), tackling each of them the mRNA of a different protein. Here, we used Escherichia coli RNase H1 as a model to study an unprecedented mode of recognition and cleavage, that is mainly dictated by the topology of our RNA·DNA-based hybrid construct. As a model system for our technology we have created 3ASO constructs designed to specifically inhibit the expression of HER2, Akt and Hsp27 in HER2+ breast cancer cells. These trifunctional ON tools displayed very low toxicity and good levels of antiproliferative activity in HER2+ breast cancer cells. The present study will be of great potential in the fight against complex pathologies involving multiple mRNA targets, as the proposed cleavable designs will allow the efficient single-dose administration of different ON drugs simultaneously.

Coordination-Driven Self-Assembly of Metal Ion-Antisense Oligonucleotide Nanohybrids for Chronic Bacterial Infection Therapy

Bacterial infection poses a significant challenge to wound healing and skin regeneration, leading to substantial economic burdens on patients and society. Therefore, it is crucial to promptly explore and develop effective methodologies for bacterial infections. Herein, we propose a novel approach for synthesizing nanostructures based on antisense oligonucleotides (ASOs) through the coordination-driven self-assembly of Zn2+ with ASO molecules. This approach aims to provide effective synergistic therapy for chronic wound infections caused by Staphylococcus aureus (S. aureus). The resulting hybrid nanoparticles successfully preserve the structural integrity and biological functionalities of ASOs, demonstrating excellent ASO encapsulation efficiency and bioaccessibility. In vitro antibacterial experiments reveal that Zn-ASO NPs exhibit antimicrobial properties against Escherichia coli, Staphylococcus aureus, and Bacillus subtilis. This antibacterial ability is attributed to the high concentration of metal zinc ions and the generation of high levels of reactive oxygen species. Additionally, the ftsZ-ASO effectively inhibits the expression of the ftsZ gene, further enhancing the antimicrobial effect. In vivo antibacterial assays demonstrate that the Zn-ASO NPs promote optimal skin wound healing and exhibit favorable biocompatibility against S. aureus infections, resulting in a residual infected area of less than 8%. This combined antibacterial strategy, which integrates antisense gene therapy and metal-coordination-directed self-assembly, not only achieves synergistic and augmented antibacterial outcomes but also expands the horizons of ASO coordination chemistry. Moreover, it addresses the gap in the antimicrobial application of metal-coordination ASO self-assembly, thereby advancing the field of ASO-based therapeutic approaches.

Smart Stimuli-Responsive Spherical Nucleic Acids: Cutting-Edge Platforms for Biosensing, Bioimaging, and Therapeutics

Spherical nucleic acids (SNAs) with exceptional colloidal stability, multiple modularity, and programmability are excellent candidates to address common molecular delivery-related issues. Based on this, the higher targeting accuracy and enhanced controllability of stimuli-responsive SNAs render them precise nanoplatforms with inestimable prospects for diverse biomedical applications. Therefore, tailored diagnosis and treatment with stimuli-responsive SNAs may be a robust strategy to break through the bottlenecks associated with traditional nanocarriers. Various stimuli-responsive SNAs are engineered through the incorporation of multifunctional modifications to meet biomedical demands with the development of nucleic acid functionalization. This review provides a comprehensive overview of prominent research in this area and recent advancements in the utilization of stimuli-responsive SNAs in biosensing, bioimaging, and therapeutics. For each aspect, SNA nanoplatforms that exhibit responsive behavior to both internal stimuli (including sequence, enzyme, redox reactions, and pH) and external stimuli (such as light and temperature) are highlighted. This review is expected to offer inspiration and guidance strategies for the rational design and development of stimuli-responsive SNAs in the field of biomedicine.

Efficient one-pot assembly of higher-order DNA nanostructures by chemically conjugated branched DNA

Chemically conjugated branched DNA was successfully synthesized by a copper-free click reaction to construct sophisticated and higher-order polyhedral DNA nanostructures with pre-defined units in one pot, which can be used as an efficient nanoplatform to precisely organize multiple gold nanoparticles in predesigned patterns.

Personalized Cancer Nanomedicine: Overcoming Biological Barriers for Intracellular Delivery of Biopharmaceuticals

The success of personalized medicine in oncology relies on using highly effective and precise therapeutic modalities such as small interfering RNA (siRNA) and monoclonal antibodies (mAbs). Unfortunately, the clinical exploitation of these biological drugs has encountered obstacles in overcoming intricate biological barriers. Drug delivery technologies represent a plausible strategy to overcome such barriers, ultimately facilitating the access to intracellular domains. Here, an overview of the current landscape on how nanotechnology has dealt with protein corona phenomena as a first and determinant biological barrier is presented. This continues with the analysis of strategies facilitating access to the tumor, along with conceivable methods for enhanced tumor penetration. As a final step, the cellular barriers that nanocarriers must confront in order for their biological cargo to reach their target are deeply analyzed. This review concludes with a critical analysis and future perspectives of the translational advances in personalized oncological nanomedicine.

Chemically Conjugated Branched Staples for Super-DNA Origami

DNA origami, comprising a long folded DNA scaffold and hundreds of linear DNA staple strands, has been developed to construct various sophisticated structures, smart devices, and drug delivery systems. However, the size and diversity of DNA origami are usually constrained by the length of DNA scaffolds themselves. Herein, we report a new paradigm of scaling up DNA origami assembly by introducing a novel branched staple concept. Owing to their covalent characteristics, the chemically conjugated branched DNA staples we describe here can be directly added to a typical DNA origami assembly system to obtain super-DNA origami with a predefined number of origami tiles in one pot. Compared with the traditional two-step coassembly system (yields <10%), a much greater yield (>80%) was achieved using this one-pot strategy. The diverse superhybrid DNA origami with the combination of different origami tiles can be also efficiently obtained by the hybrid branched staples. Furthermore, the branched staples can be successfully employed as the effective molecular glues to stabilize micrometer-scale, super-DNA origami arrays (e.g., 10 × 10 array of square origami) in high yields, paving the way to bridge the nanoscale precision of DNA origami with the micrometer-scale device engineering. This rationally developed assembly strategy for super-DNA origami based on chemically conjugated branched staples presents a new avenue for the development of multifunctional DNA origami-based materials.

In Situ Vaccination with An Injectable Nucleic Acid Hydrogel for Synergistic Cancer Immunotherapy

Recently, therapeutic cancer vaccines have emerged as promising candidates for cancer immunotherapy. Nevertheless, their efficacies are frequently impeded by challenges including inadequate antigen encapsulation, insufficient immune activation, and immunosuppressive tumor microenvironment. Herein, we report a three-in-one hydrogel assembled by nucleic acids (NAs) that can serve as a vaccine to in situ trigger strong immune response against cancer. Through site-specifically grafting the chemodrug, 7-ethyl-10-hydroxycamptothecin (also known as SN38), onto three component phosphorothioate (PS) DNA strands, a Y-shaped motif (Y-motif) with sticky ends is self-assembled, at one terminus of which an unmethylated cytosine-phosphate-guanine (CpG) segment is introduced as an immune agonist. Thereafter, programmed cell death ligand-1 (PD-L1) siRNA that performs as immune checkpoint inhibitor is designed as a crosslinker to assemble with the CpG- and SN38-containing Y-motif, resulting in the formation of final NA hydrogel vaccine. With three functional agents inside, the hydrogel can remarkably induce the immunogenic cell death to enhance the antigen presentation, promoting the dendritic cell maturation and effector T lymphocyte infiltration, as well as relieving the immunosuppressive tumor environment. When inoculated twice at tumor sites, the vaccine demonstrates a substantial antitumor effect in melanoma mouse model, proving its potential as a general platform for synergistic cancer immunotherapy.

Specific interaction based drug loading strategies

Drug carriers have been commonly used for drug control release, enhancing drug efficacy and/or minimizing side-effects. However, it is still difficult to get a high loading efficiency when encapsulating super hydrophilic drugs with a narrow therapeutic index, such as many neurotoxins. Increasing the carrier proportion can improve drug loading to a certain degree, while the burst released drug when the formulation enters the body may cause overdose side-effects. Moreover, high-dose carriers themselves may increase the metabolic burden of the body. Hence, new drug carriers and/or loading strategies are urgently needed to promote the applications of these drugs. This minireview will introduce drug loading strategies based on specific interactions (between drugs and carriers) and will discuss the challenges and perspectives of these strategies. This work is expected to provide alternative inspiration for the delivery of hydrophilic drugs.

RNA Nanomedicine: Delivery Strategies and Applications

Delivery of RNA using nanomaterials has emerged as a new modality to expand therapeutic applications in biomedical research. However, the delivery of RNA presents unique challenges due to its susceptibility to degradation and the requirement for efficient intracellular delivery. The integration of nanotechnologies with RNA delivery has addressed many of these challenges. In this review, we discuss different strategies employed in the design and development of nanomaterials for RNA delivery. We also highlight recent advances in the pharmaceutical applications of RNA delivered via nanomaterials. Various nanomaterials, such as lipids, polymers, peptides, nucleic acids, and inorganic nanomaterials, have been utilized for delivering functional RNAs, including messenger RNA (mRNA), small interfering RNA, single guide RNA, and microRNA. Furthermore, the utilization of nanomaterials has expanded the applications of functional RNA as active pharmaceutical ingredients. For instance, the delivery of antigen-encoding mRNA using nanomaterials enables the transient expression of vaccine antigens, leading to immunogenicity and prevention against infectious diseases. Additionally, nanomaterial-mediated RNA delivery has been investigated for engineering cells to express exogenous functional proteins. Nanomaterials have also been employed for co-delivering single guide RNA and mRNA to facilitate gene editing of genetic diseases. Apart from the progress made in RNA medicine, we discuss the current challenges and future directions in this field.

mRNA-activated DNAzyme nanoprobe for tumor cell precise imaging and gene therapy

A novel Au-nucleic acid nanoprobe, catalyzed by mRNA, has been developed for live cell imaging and precise treatment of tumor cells. This nanoprobe exhibits the remarkable ability to differentiate between tumor cells and normal cells through live cell mRNA imaging, while selectively inducing apoptosis in tumor cells.

Nanoporous Crystalline Materials for the Recognition and Applications of Nucleic Acids

Nucleic acid plays a crucial role in countless biological processes. Hence, there is great interest in its detection and analysis in various fields from chemistry, biology, to medicine. Nanoporous crystalline materials exhibit enormous potential as an effective platform for nucleic acid recognition and application. These materials have highly ordered and uniform pore structures, as well as adjustable surface chemistry and pore size, making them good carriers for nucleic acid extraction, detection, and delivery. In this review, the latest developments in nanoporous crystalline materials, including metal organic frameworks (MOFs), covalent organic frameworks (COFs), and supramolecular organic frameworks (SOFs) for nucleic acid recognition and applications are discussed. Different strategies for functionalizing these materials are explored to specifically identify nucleic acid targets. Their applications in selective separation and detection of nucleic acids are highlighted. They can also be used as DNA/RNA sensors, gene delivery agents, host DNAzymes, and in DNA-based computing. Other applications include catalysis, data storage, and biomimetics. The development of novel nanoporous crystalline materials with enhanced biocompatibility has opened up new avenues in the fields of nucleic acid analysis and therapy, paving the way for the development of sensitive, selective, and cost-effective diagnostic and therapeutic tools with widespread applications.

Programming conformational cooperativity to regulate allosteric protein-oligonucleotide signal transduction

Conformational cooperativity is a universal molecular effect mechanism and plays a critical role in signaling pathways. However, it remains a challenge to develop artificial molecular networks regulated by conformational cooperativity, due to the difficulties in programming and controlling multiple structural interactions. Herein, we develop a cooperative strategy by programming multiple conformational signals, rather than chemical signals, to regulate protein-oligonucleotide signal transduction, taking advantage of the programmability of allosteric DNA constructs. We generate a cooperative regulation mechanism, by which increasing the loop lengths at two different structural modules induced the opposite effects manifesting as down- and up-regulation. We implement allosteric logic operations by using two different proteins. Further, in cell culture we demonstrate the feasibility of this strategy to cooperatively regulate gene expression of PLK1 to inhibit tumor cell proliferation, responding to orthogonal protein-signal stimulation. This programmable conformational cooperativity paradigm has potential applications in the related fields.

Carbon Dots with Guanidinium and Amino Acid Functional Groups for Targeted Small Interfering RNA Delivery toward Tumor Gene Therapy

Small interfering RNA (siRNA)-based gene therapy represents a promising strategy for tumor treatment. Novel gene vectors that can achieve targeted delivery of siRNA to the tumor cells without causing any side effects are urgently needed. To this end, the large amino acid mimicking carbon dots with guanidinium functionalization (LAAM GUA-CDs) are designed and synthesized by choosing arginine and dopamine hydrochloride as precursors. LAAM GUA-CDs can load siRNA through the multiple hydrogen bonds between their guanidinium groups and phosphate groups in siRNA. Meanwhile, the amino acid groups at the edges of LAAM GUA-CDs endow them the capacity to target tumors. After loading siBcl-2 as a therapeutic agent, LAAM GUA-CDs/siBcl-2 has a high tumor inhibition rate of up to 68%, which is twice more than that of commercial Lipofectamine 2000. Furthermore, LAAM GUA-CDs do not cause side effect during antitumor treatment owing to their high tumor-targeting ability, thus providing a versatile strategy for tumor-targeted siRNA delivery and cancer therapy.

Cyclodextrins as eminent constituents in nanoarchitectonics for drug delivery systems

Cyclodextrins have been widely employed for drug delivery systems (DDSs) in which drugs are selectively delivered to a target site in the body. Recent interest has been focused on the construction of cyclodextrin-based nanoarchitectures that show sophisticated DDS functions. These nanoarchitectures are precisely fabricated based on three important features of cyclodextrins, namely (1) the preorganized three-dimensional molecular structure of nanometer size, (2) the easy chemical modification to introduce functional groups, and (3) the formation of dynamic inclusion complexes with various guests in water. With the use of photoirradiation, drugs are released from cyclodextrin-based nanoarchitectures at designated timing. Alternatively, therapeutic nucleic acids are stably protected in the nanoarchitectures and delivered to the target site. The efficient delivery of the CRISPR-Cas9 system for gene editing was also successful. Even more complicated nanoarchitectures can be designed for sophisticated DDSs. Cyclodextrin-based nanoarchitectures are highly promising for future applications in medicine, pharmaceutics, and other relevant fields.

Oral delivery of nucleic acid therapeutics: Challenges, strategies, and opportunities

In recent decades, advances in chemical synthesis and delivery systems have accelerated the development of therapeutic nucleic acids, several of which have been approved by the Us Food and Drug Administration (FDA). Oral nucleic acid delivery is preferred because of its simplicity and patient compliance, but it still presents distinct challenges. The negative charge, hydrophilicity, and large molecular weight of nucleic acids combined with in vivo gastrointestinal (GI) barriers (e.g., acidic pH, enzymes, mucus, and intestinal epithelial cells) severely hinder their delivery efficacy. Recently, various nanoparticles (NPs), ranging from polymeric to lipid-based (L)NPs and extracellular vesicles (EVs), have been extensively explored to address these obstacles. In this review, we describe the physiological barriers in the GI tract and summarize recent advances in NP-based oral nucleic acid therapeutics.

Nucleic acid-based artificial nanocarriers for gene therapy

Nucleic acid nanotechnology is a powerful tool in the fields of biosensing and nanomedicine owing to their high editability and easy synthesis and modification. Artificial nucleic acid nanostructures have become an emerging research hotspot as gene carriers with low cytotoxicity and immunogenicity for therapeutic approaches. In this review, recent progress in the design and functional mechanisms of nucleic acid-based artificial nano-vectors especially for exogenous siRNA and antisense oligonucleotide delivery is summarized. Different types of DNA nanocarriers, including DNA junctions, tetrahedrons, origami, hydrogels and scaffolds, are introduced. The enhanced targeting strategies to improve the delivery efficacy are demonstrated. Furthermore, RNA based gene nanocarrier systems by self-assembly of short strands, rolling circle transcription, chemical crosslinking and using RNA motifs and DNA-RNA hybrids are demonstrated. Finally, the outlook and potential challenges are highlighted. The nucleic acid-based artificial nanocarriers offer a promising and precise tool for gene delivery and therapy.

Stimuli-responsive nucleic acid nanostructures for efficient drug delivery

Based on complementary base pairing, nucleic acid molecules have acted as engineerable building blocks to prepare versatile nanostructures with unique shapes and sizes. Benefiting from excellent programmability and biocompatibility, rationally designed nucleic acid nanostructures have been widely employed in biomedical applications. With the development of the chemical biology of nucleic acids, various stimuli-responsive nucleic acid nanostructures have been constructed by tailored chemical modification with multifunctional components. In this minireview, we summarize the representative and latest research about the employment of stimuli-responsive nucleic acid nanostructures for drug delivery in response to endogenous and exogenous stimuli (redox gradient, pH, nuclease, biomacromolecule, and light). We also discuss the broad prospects and remaining challenges of nucleic acid nanotechnology in biomedical applications.

Nanoparticle entry into cells; the cell biology weak link

Nanoparticles (NP) are attractive options for the therapeutic delivery of active pharmaceutical drugs, proteins and nucleic acids into cells, tissues and organs. Research into the development and application of NP most often starts with a diverse group of scientists, including chemists, bioengineers and material and pharmaceutical scientists, who design, fabricate and characterize NP in vitro (Stage 1). The next step (Stage 2) generally investigates cell toxicity as well as the processes by which NP bind, are internalized and deliver their cargo to appropriate model tissue culture cells. Subsequently, in Stage 3, selected NP are tested in animal systems, mostly mouse. Whereas the chemistry-based development and analysis in Stage 1 is increasingly sophisticated, the investigations in Stage 2 are not what could be regarded as 'state-of-the-art' for the cell biology field and the quality of research into NP interactions with cells is often sub-standard. In this review we describe our current understanding of the mechanisms by which particles gain entry into mammalian cells via endocytosis. We summarize the most important areas for concern, highlight some of the most common mis-conceptions, and identify areas where NP scientists could engage with trained cell biologists. Our survey of the different mechanisms of uptake into cells makes us suspect that claims for roles for caveolae, as well as macropinocytosis, in NP uptake into cells have been exaggerated, whereas phagocytosis has been under-appreciated.

G-Quadruplex-Proximized Aptamers (G4PA) Efficiently Targeting Cell-Surface Transferrin Receptors for Targeted Cargo Delivery

DNA-assembled multiaptamer systems have been demonstrated to significantly promote the aptamer capacity of binding cell-surface-expressed proteins. However, how to conveniently harness them for efficient transmembrane delivery of targets remains a challenge. Toward this goal, here we engineer a G-quadruplex-proximized aptamer (G4PA) system in which a DNA aptamer specific for transferrin receptor (TfR) is guided by a bimolecular G4 and assembles into a dimerized proximity form that well matches homodimeric TfR highly expressed on the cancer cell surface. This system displays a higher capacity for targeting cell-surface TfR than the monomeric aptamer and super transmembrane transportation of nucleic acid cargoes, which is comparable to that of conventional liposome transfection but overcomes the lack of targeting ability of the latter. The G4PA system is then applied to the targeted delivery of siRNA for PLK1 gene silencing in positive cells rather than negative controls, showing great promise for use in precise anticancer therapy.

Artificial primary-miRNAs as a platform for simultaneous delivery of siRNA and antisense oligonucleotide for multimodal gene regulation

Self-assembled nucleic acid nanostructures have been widely explored for gene therapy applications due to their unique advantages. Their roles are not limited to offer intracellular delivery platforms but additionally provide a biological function to induce targeted gene regulation. Here, we report a self-assembled artificial primary-miRNA (pri-miRNA) for achieving simultaneous multimodal gene regulation. Artificial pri-miRNAs are designed to play a role as substrate RNAs to recruit and interact with Drosha/DGCR8 (Microprocessor). Incorporation of functional RNA motifs and site-specific chemical modification of the primary miRNA are utilized for the biogenesis of two individual gene-regulating oligonucleotides. Once they are cleaved by the endogenous Drosha/DGCR8 complex, basal strands and pre-miRNA can be generated inside of cells. In this study, we integrated basal strands with either SMN2 ASO or anti-miR21 to induce multimodal gene regulation. Microprocessing and subsequent gene regulation were first evaluated by measuring the activity of reporter pre-miRNA. Chemical modification on the primary miRNA was optimized through a series of in vitro Drosha cleavage tests and targeted gene silencing in cells. Primary miRNA with the basal ASO or anti-miR strands showed a successful in vitro activity and resulted in simultaneous multimodal gene regulation in cells. Artificial primary miRNA may offer synergistic therapeutic effects for treating various diseases, including spinal muscular atrophy and cancer.

Tumor microenvironment responsive nanocarriers for gene therapy

Stimuli responsive nanocarriers are important non-viral gene carriers for gene therapy. We discuss the stimulus conditions and then highlight various stimuli responsive nanocarriers in the tumor microenvironment for cancer gene therapy. We hope that this review will inspire readers to develop more effective stimuli responsive nanocarriers for delivering genes.

A covalently conjugated branched DNA aptamer cluster-based nanoplatform for efficiently targeted drug delivery

Targeted delivery of therapeutic drugs is essential for precise treatment of various diseases to reduce possible serious side-effects. A screened DNA aptamer has been widely developed for active targeting delivery. Herein, we report a facile strategy for the construction of a branched DNA aptamer cluster-based nanoplatform for efficiently targeted drug delivery. In our design, the terminal-modified DNA aptamer can be covalently conjugated to form a branched aptamer cluster by click reaction easily. The branched aptamer cluster-modified DNA tetrahedron (TET) demonstrates highly targeted cellular uptake with the modification of only one site. After loading the chemotherapeutic drug (doxorubicin, DOX), the DNA aptamer cluster-based nanoplatform elicits a remarkable and selective inhibition of tumor cell proliferation by much-enhanced targeted delivery. This covalently conjugated branched DNA aptamer cluster-based nanoplatform provides a new strategy for the development of targeted drug delivery.

Smart Drug Delivery Systems Based on DNA Nanotechnology

The development of DNA nanotechnology has attracted tremendous attention in biotechnological and biomedical fields involving biosensing, bioimaging and disease therapy. In particular, precise control over size and shape, easy modification, excellent programmability and inherent homology make the sophisticated DNA nanostructures vital for constructing intelligent drug carriers. Recent advances in the design of multifunctional DNA-based drug delivery systems (DDSs) have demonstrated the effectiveness and advantages of DNA nanostructures, showing the unique benefits and great potential in enhancing the delivery of pharmaceutical compounds and reducing systemic toxicity. This Review aims to overview the latest researches on DNA nanotechnology-enabled nanomedicine and give a perspective on their future opportunities.

Biomineralized Cascade Enzyme-Encapsulated ZIF-8 Nanoparticles Combined with Antisense Oligonucleotides for Drug-Resistant Bacteria Treatment

The unrestrained use of antibiotics accelerates the development of drug-resistant bacteria and leads to an increasing threat to human health. Therefore, there is an urgent need to explore novel and effective strategies for the treatment of bacterial infections. Herein, zeolite imidazole framework-8 (ZIF-8) material was utilized to construct biomineralized nanomaterial (GOx&HRP@ZIF-8/ASO) by encapsulating biological cascade enzymes and combining with antisense oligonucleotides (ASOs), which achieved effective and synergistic antidrug-resistant bacteria therapy. Various in vitro assays confirmed that GOx&HRP@ZIF-8/ASO exhibited excellent antibacterial properties against Escherichia coli, Staphylococcus aureus, methicillin-resistant S. aureus (MRSA) during catalysis of glucose (Glu), especially the minimum inhibitory concentration (MIC) against MRSA was only 16 μg/mL. Compared with simple ZIF-8 (32.85%) and ftsZ ASO (58.65%), GOx&HRP@ZIF-8/ASO+Glu exhibited superb biofilm destruction ability, and the bacteria removal efficiency of the MRSA biofilm could be as high as 88.2%, indicating that the reactive oxygen species (ROS) produced by the cascade enzyme reaction imparted the main synergistic antibacterial capability, and simultaneously, ftsZ ASO significantly enhanced the antibacterial effect by inhibiting the expression of the ftsZ gene. In vivo anti-infection treatment experiments revealed that GOx&HRP@ZIF-8/ASO exhibited the best wound repairing performance and excellent biocompatibility in the presence of Glu. These findings suggested that GOx&HRP@ZIF-8/ASO has favorably realized high-efficiency treatment of MRSA infection and filled the gap in the antibacterial application of biological enzymes.

Chemically Modified DNA Nanostructures for Drug Delivery

Based on predictable, complementary base pairing, DNA can be artificially pre-designed into versatile DNA nanostructures of well-defined shapes and sizes. With excellent addressability and biocompatibility, DNA nanostructures have been widely employed in biomedical research, such as bio-sensing, bio-imaging, and drug delivery. With the development of the chemical biology of nucleic acid, chemically modified nucleic acids are also gradually developed to construct multifunctional DNA nanostructures. In this review, we summarize the recent progress in the construction and functionalization of chemically modified DNA nanostructures. Their applications in the delivery of chemotherapeutic drugs and nucleic acid drugs are highlighted. Furthermore, the remaining challenges and future prospects in drug delivery by chemically modified DNA nanostructures are discussed.

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With excellent addressability and biocompatibility, DNA nanostructures are promising candidates for bio-sensing, bio-imaging, and drug delivery

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The recent progress in chemical modifications of DNA nanostructures is summarized

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Chemically modified DNA nanostructures for efficient delivery of chemotherapeutic drugs and nucleic acid drugs are highlighted

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Challenges and prospects of future development toward chemically modified DNA nanostructures for drug delivery are discussed

RNA Drug Delivery Using Biogenic Nanovehicles for Cancer Therapy

RNA-based therapies have been promising method for treating all kinds of diseases, and four siRNA-based drugs and two mRNA-based drugs have been approved and are on the market now. However, none of them is applied for cancer treatment. This is not only because of the complexity of the tumor microenvironment, but also due to the intrinsic obstacles of RNAs. Until now, all kinds of strategies have been developed to improve the performance of RNAs for cancer therapy, especially the nanoparticle-based ones using biogenic materials. They are much more compatible with less toxicity compared to the ones using synthetic polymers, and the most widely studied biogenic materials are oligonucleotides, exosomes, and cell membranes. Particular characteristics make them show different capacities in internalization and endosomal escape as well as specific targeting. In this paper, we systematically summarize the RNA-based nano-delivery systems using biogenic materials for cancer therapy, and we believe this review will provide a valuable reference for researchers involved in the field of biogenic delivery and RNA-based therapies for cancer treatment.

Non-viral vectors for RNA delivery

RNA-based therapy is a promising and potential strategy for disease treatment by introducing exogenous nucleic acids such as messenger RNA (mRNA), small interfering RNA (siRNA), microRNA (miRNA) or antisense oligonucleotides (ASO) to modulate gene expression in specific cells. It is exciting that mRNA encoding the spike protein of COVID-19 (coronavirus disease 2019) delivered by lipid nanoparticles (LNPs) exhibits the efficient protection of lungs infection against the virus. In this review, we introduce the biological barriers to RNA delivery in vivo and discuss recent advances in non-viral delivery systems, such as lipid-based nanoparticles, polymeric nanoparticles, N-acetylgalactosamine (GalNAc)-siRNA conjugate, and biomimetic nanovectors, which can protect RNAs against degradation by ribonucleases, accumulate in specific tissue, facilitate cell internalization, and allow for the controlled release of the encapsulated therapeutics.

A DNA–Au nanomachine activated by dual types of biomarkers for multi-site imaging and gene silencing

A programmed DNA–Au nanomachine was constructed to achieve in situ imaging of the transmembrane glycoprotein MUC1 and cytoplasmic miRNA-21 and trigger precise gene silencing therapy for breast cancer.

SiRNA-templated 3D framework nucleic acids for chemotactic recognition, and programmable and visualized precise delivery for synergistic cancer therapy

Developments in framework nucleic acids (FNAs) are limited by complicated synthesis, by-product interference, and low framework utilization. Herein, simple core-shell spherical 3D FNAs (ST-SFNAs) preparation is presented based on siRNA-templated linear polymerization followed by hybridization chain reaction branched polymerization. Without by-products, all components exhibited their special functions to obtain high space utilization of ST-SFNAs. ST-SFNAs were covered by catalase and folic acid-functionalized liposome membranes. The catalase endowed ST-SFNAs with chemotactic activities in the H₂O₂ reaction catalyzed by catalase. Furthermore, combined with functionalized folic acids' targeting folate receptors, the synergistic chemotactic recognition of cancer cells was obtained. This dramatically promoted targeted cellular uptakes compared with traditional active or passive targeting pathways. Subsequently, the cascaded-logical programmable release of drugs was precisely controlled by targeting glutathione and ATP (via S-S bond and ATP aptamer on the inner g-DNA cover). This was visualized by "turn on" fluorescent signals generated by special hybridization of released hairpin DNAs with survivin mRNA biomarkers. Simultaneously, biocompatible synergistic therapy was achieved by simultaneously releasing doxorubicin and siRNA. With its high utilization for synergistic chemotactic recognition, programmable and visualized delivery, as well as synergistic therapy, an efficient platform for maximizing the therapeutic efficacy has been developed. This would initiate further FNA-based material development for a variety of biological applications.

Hierarchical Assembly of Super-DNA Origami Based on a Flexible and Covalent-Bound Branched DNA Structure

DNA origami technique provides a programmable way to construct nanostructures with arbitrary shapes. The dimension of assembled DNA origami, however, is usually limited by the length of the scaffold strand. Herein, we report a general strategy to efficiently organize multiple DNA origami tiles to form super-DNA origami using a flexible and covalent-bound branched DNA structure. In our design, the branched DNA structures (B_n: with a certain number of 2-6 branches) are synthesized by a copper-free click reaction. Equilateral triangular DNA origamis with different numbers of capture strands (T_n: T₁, T₂, and T₃) are constructed as the coassembly tiles. After hybridization with the branched DNA structures, the super-DNA origami (up to 13 tiles) can be efficiently ordered in the predesigned patterns. Compared with traditional DNA junctions (J_n: J₂-J₆, as control groups) assembled by base pairing between several DNA strands, a higher yield and more compact structures are obtained using our strategy. The highly ordered and discrete DNA origamis can further precisely organize gold nanoparticles into different patterns. This rationally developed DNA origami ordering strategy based on the flexible and covalent-bound branched DNA structure presents a new avenue for the construction of sophisticated DNA architectures with larger molecular weights.

Macrocyclic host molecules with aromatic building blocks: the state of the art and progress

Macrocyclic host molecules play the central role in host-guest chemistry and supramolecular chemistry. The highly structural symmetry of macrocyclic host molecules can meet people's pursuit of aesthetics in molecular design, and generally means a balance of design, synthesis, properties and applications. For macrocyclic host molecules with highly symmetrical structures, building blocks, which could be described as repeat units as well, are the most fundamental elements for molecular design. The structural features and recognition ability of macrocyclic host molecules are determined by the building blocks and their connection patterns. Using different building blocks, different macrocyclic host molecules could be designed and synthesized. With decades of developments of host-guest chemistry and supramolecular chemistry, diverse macrocyclic host molecules with different building blocks have been designed and synthesized. Aromatic building blocks are a big family among the various building blocks used in constructing macrocyclic host molecules. In this feature article, the recent developments of macrocyclic host molecules with aromatic building blocks were summarized and discussed.

DNA Functional Nanomaterials for Controlled Delivery of Nucleic Acid-Based Drugs

Nucleic acid-based drugs exhibited great potential in cancer therapeutics. However, the biological instability of nucleic acid-based drugs seriously hampered their clinical applications. Efficient in vivo delivery is the key to the clinical application of nucleic acid-based drugs. As a natural biological macromolecule, DNA has unique properties, such as excellent biocompatibility, molecular programmability, and precise assembly controllability. With the development of DNA nanotechnology, DNA nanomaterials have demonstrated significant advantages as delivery vectors of nucleic acid-based drugs by virtue of the inherent nucleic acid properties. In this study, the recent progress in the design of DNA-based nanomaterials for nucleic acid delivery is summarized. The DNA nanomaterials are categorized according to the components including pure DNA nanomaterials, DNA-inorganic hybrid nanomaterials, and DNA-organic hybrid nanomaterials. Representative applications of DNA nanomaterials in the controlled delivery of nucleic acid-based drugs are exemplified to show how DNA nanomaterials are rationally and exquisitely designed to address application issues in cancer therapy. At the end of this study, the challenges and future development of DNA nanomaterials are discussed.

Targeted Delivery of Drugs and Genes Using Polymer Nanocarriers for Cancer Therapy

Cancer is one of the primary causes of worldwide human deaths. Most cancer patients receive chemotherapy and radiotherapy, but these treatments are usually only partially efficacious and lead to a variety of serious side effects. Therefore, it is necessary to develop new therapeutic strategies. The emergence of nanotechnology has had a profound impact on general clinical treatment. The application of nanotechnology has facilitated the development of nano-drug delivery systems (NDDSs) that are highly tumor selective and allow for the slow release of active anticancer drugs. In recent years, vehicles such as liposomes, dendrimers and polymer nanomaterials have been considered promising carriers for tumor-specific drug delivery, reducing toxicity and improving biocompatibility. Among them, polymer nanoparticles (NPs) are one of the most innovative methods of non-invasive drug delivery. Here, we review the application of polymer NPs in drug delivery, gene therapy, and early diagnostics for cancer therapy.

Stimuli-Responsive and Highly Penetrable Nanoparticles as a Multifunctional Nanoplatform for Boosting Nonsmall Cell Lung Cancer siRNA Therapy

In cancer therapy, it is acknowledged that large-size nanoparticles stay in the circulation system for a long time, but their permeability to tumor tissues is poor. To address the conflicting need for prolonging circulation time and favorable tumor tissue penetration ability, a charge conversional multifunctional nanoplatform was strategically designed to improve the efficacy of small interfering RNA (siRNA) therapy against nonsmall cell lung cancer (NSCLC). The development of nanodrug delivery systems (NDDSs) was constructed by loading siRNA on polyamidoamine (PAMAM) dendrimers to build small-sized PAM/siRNA via electrostatic interaction and then capped with a pH-triggered copolymer poly(ethylene glycol) methyl ether (mPEG)-poly-l-lysine (PLL)-2,3-dimethylmaleic anhydride (DMA) (shorted as PLM) under physiological conditions. While in the tumor microenvironment, the acidic reaction of the PLM copolymer changes from negative charge to positive charge due to the cleavable amide bond between mPEG-PLL and DMA, leading to large-size nanoparticles (NPs) with a negative charge that turns into a positive charge and small NPs with a high tumor-penetrating ability. All of the in vitro and in vivo studies validated that PLM/PAM/siRNA NPs possess desirable features including excellent biocompatibility, a prolonged circulation time, significant pH sensitivity, high tumor tissue penetration ability, and sufficient endo-/lysosomal escape. Taken together, all results suggest tremendous potential of the gene therapy based on the stimuli-sensitive PLM/PAM/siRNA NPs, providing a profound application prospective treatment strategy in cancer gene therapy.