An Intelligent DNA Nanorobot with in Vitro Enhanced Protein Lysosomal Degradation of HER2

Entropy driven-based catalytic biosensors for bioanalysis: From construction to application-A review

The rapid advancement of precision medicine and the continuous emergence of novel pathogens have presented new challenges for biosensors, necessitating higher requirements. Target amplification technology serves as the core component in biosensor construction. Enzyme-based amplification methods are often sensitive and selective but involve relatively complex operational steps, whereas enzyme-free amplification methods offer simplicity but frequently fail to meet both sensitivity and selectivity simultaneously. Existing research has confirmed that entropy-driven catalyst (EDC) biosensors not only fulfills the demands for sensitivity and selectivity concurrently but also offers ease of operation and flexibility in construction. In this review, we summarize the key advantages of EDC, explore how to construct DNA nanomachines based on these advantages to achieve intracellular detection and simultaneous detection of multiple targets, as well as point-of-care testing (POCT) to address practical issues in clinical diagnosis and treatment. We also anticipate potential challenges, propose corresponding solutions, and outline future development directions for EDC-based biosensors in practical clinical applications. We firmly believe that EDC sensors will emerge as a crucial branch within the realm of biosensor development.

Nanotechnology-based biomedical devices in the cancer diagnostics and therapy

Nanotechnology has significantly transformed the field of cancer diagnostics and therapeutics by introducing advanced biomedical devices. These nanotechnology-based devices exhibit remarkable capabilities in detecting and treating various cancers, addressing the limitations of traditional approaches, such as limited specificity and sensitivity. This review aims to explore the advancements in nanotechnology-driven biomedical devices, emphasizing their role in the diagnosis and treatment of cancer. Through a comprehensive analysis, we evaluate various nanotechnology-based devices across different cancer types, detailing their diagnostic and therapeutic effectiveness. The review also discusses FDA-approved nanotechnology products, patents, and regulatory trends, highlighting the innovation and clinical impact in oncology. Nanotechnology-based devices, including nanobots, smart pills, and multifunctional nanoparticles, enable precise targeting and treatment, reducing adverse effects on healthy tissues. Devices such as DNA-based nanorobots, quantum dots, and biodegradable stents offer noninvasive diagnostic and therapeutic options, showing high efficacy in preclinical and clinical settings. FDA-approved products underscore the acceptance of these technologies. Nanotechnology-based biomedical devices offer a promising future for oncology, with the potential to revolutionize cancer care through early detection, targeted treatment, and minimal side effects. Continued research and technological improvements are essential to fully realize their potential in personalized cancer therapy.

Precise Preparation of Supramolecular Spherical Nucleic Acids for Nucleolin-Targeted Gene Delivery

Molecular spherical nucleic acids (m-SNAs) are a second generation of spherical nucleic acids (SNAs), which are of significance in potential application of targeted delivery of nucleic acids or gene regulation due to their defined molecular structures. Nevertheless, m-SNAs typically involve a single DNA sequence which greatly limits its functions as either targeting purpose or gene regulation. In response, we proposed here a third generation, supramolecular spherical nucleic acids (Supra-SNAs) with two different sequences to achieve both above-mentioned functions. Specifically, we constructed a series of supramolecular self-assembly structures by coupling a cell membrane receptor (i.e., nucleolin)-recognizing aptamer (AS1411)-modified adamantine as targeting probe and human epithelial growth factor receptor 2 (HER2) antisense-functionalized β-cyclodextrin to specifically inhibit the overexpression of HER2 proteins for gene regulations. In comparison to the m-SNA precursors, such Supra-SNA structures exhibited enhanced levels of resistance to nuclease degradation, cellular uptake, gene regulation capabilities and tumor retention capacity. We demonstrated that Supra-SNAs exhibited optimal cell suppression rates and cell apoptosis via a phosphatidylinositol 3-kinase/protein kinase B signaling pathway. The well-defined molecular structures provide an attractive platform for investigating interrelationship between structure and property at the molecular level.

Nanomolecular machines: Pioneering precision medicine for neoplastic diseases through advanced diagnosis and treatment

Tumors pose a major threat to human health, accounting for nearly one-sixth of global deaths annually. The primary treatments include surgery, radiotherapy, chemotherapy, and immunotherapy, each associated with significant side effects. This has driven the search for new therapies with fewer side effects and greater specificity. Nanotechnology has emerged as a promising field in this regard, particularly nanomolecular machines at the nanoscale. Nanomolecular machines are typically constructed from biological macromolecules like proteins, DNA, and RNA. These machines can be programmed to perform specialized tasks with precise instructions. Recent research highlights their potential in tumor diagnostics-identifying susceptibility genes, detecting viruses, and pinpointing tumor markers. Nanomolecular machines also offer advancements in tumor therapy. They can reduce traditional treatment side effects by delivering chemotherapy drugs and enhancing immunotherapy, and they support innovative treatments like sonodynamic and phototherapy. Additionally, they can starve tumors by blocking blood vessels, and eliminate tumors by disrupting cell membranes or lysosomes. This review categorizes and explains the latest achievements in molecular machine research, explores their models, and practical clinical uses in tumor diagnosis and treatment. It aims to broaden the research perspective and accelerate the clinical adoption of these technologies.

Biohybrid Micro/Nanorobots: Pioneering the Next Generation of Medical Technology

Biohybrid micro/nanorobots hold a great potential for advancing biomedical research. These tiny structures, designed to mimic biological organisms, offer a promising method for targeted drug delivery, tissue engineering, biosensing/imaging, and cancer therapy, among other applications. The integration of biology and robotics opens new possibilities for minimally invasive surgeries and personalized healthcare solutions. The key challenges in the development of biohybrid micro/nanorobots include ensuring biocompatibility, addressing manufacturing scalability, enhancing navigation and localization capabilities, maintaining stability in dynamic biological environments, navigating regulatory hurdles, and successfully translating these innovative technologies into clinical applications. Herein, the recent advancements, challenges, and future perspectives related to the biomedical applications of biohybrid micro/nanorobots are described. Indeed, this review sheds light on the cutting-edge developments in this field, providing researchers with an updated overview of the current potential of biohybrid micro/nanorobots in the realm of biomedical applications, and offering insights into their practical applications. Furthermore, it delves into recent advancements in the field of biohybrid micro/nanorobotics, providing a comprehensive analysis of the current state-of-the-art technologies and their future applications in the biomedical field.

A multifunctional nanoplatform for chemotherapy and nanocatalytic synergistic cancer therapy achieved by amplified lipid peroxidation

Traditional cancer chemotherapy suffers from low efficacy and severe side effects, limiting its use as a first-line treatment. To address this issue, we investigated a novel way to induce lipid peroxidation (LPO), which plays an essential role in ferroptosis and may be useful against cancer cells and tumors. In this study, a pH-responsive synergistic cancer therapy nanoplatform was prepared using CaCO3 co-loaded with oleanolic acid (OA) and lipoxygenase (LOX), resulting in the formation OLCaP NP. This nanoplatform exhibited good drug release properties in an acidic tumor environment owing to the presence of CaCO3. As a result of acidic stimulation at tumor sites, the OLCaP NP released OA and LOX. OA, a chemotherapeutic drug with anticancer activity, is already known to promote the apoptosis of cancer cells, and LOX is a natural enzyme that catalyzes the oxidation of polyunsaturated fatty acids, leading to the accumulation of lipid peroxides and promoting the apoptosis of cancer cells. More importantly, OA upregulated the expression of acyl-coenzyme A synthetase long-chain family member 4 (ACSL4), which promoted enzyme-mediated LPO. Based on our combined chemotherapy and nanocatalytic therapy, the OLCaP NP not only had remarkable antitumor ability but also upregulated ACSL4 expression, allowing further amplification of LPO to inhibit tumor growth. These findings demonstrate the potential of this nanoplatform to enhance the therapeutic efficacy against tumors by inducing oxidative stress and disrupting lipid metabolism, highlighting its clinical potential for improved cancer treatment. STATEMENT OF SIGNIFICANCE: This study presents a novel nanoplatform that combines oleanolic acid (OA), a chemotherapeutic drug, and lipoxygenase (LOX), which oxidizes polyunsaturated fatty acids to trigger apoptosis, for targeted cancer therapy. Unlike traditional treatments, our nanoplatform exhibits pH-responsive drug release, specifically in acidic tumor environments. This innovation enhances the therapeutic effects of OA and LOX, upregulating acyl-CoA synthetase long-chain family member 4 expression and amplifying lipid peroxidation to promote tumor cell apoptosis. Our findings significantly advance the existing literature by demonstrating a synergistic approach that combines chemotherapy and nanocatalytic therapy. The scientific impact of this work lies in its potential to improve cancer treatment efficacy and specificity, offering a promising strategy for clinical applications and future research in cancer therapy.

Visualization of the hepatic and renal cell uptake and trafficking of tetrahedral DNA origami in tumour

DNA nanostructures, known for their programmability, ease of modification, and favourable biocompatibility, have gained widespread application in the biomedical field. Among them, Tetrahedral DNA Origami (TDOs), as a novel DNA nanostructure, possesses well-defined structures, multiple modification sites, and large cavities, making it a promising drug carrier. However, current understanding of TDOs' interactions with biological systems, particularly with target cells and organs, remains unexplored, limiting its further applications in biomedicine. In this work, we prepared TDOs with an average particle size of 40 nm and labelled them with Cy5 fluorescent molecules. Following intravenous injection in mice, the uptake of TDOs by different types of liver and kidney cells was observed. Results indicated that TDOs accumulate in renal tubules and are metabolized by Kupffer cells, epithelial cells, and hepatocytes in the liver. Additionally, in a tumour-bearing mouse model, TDOs passively targeted tumour tissues and exhibited excellent tumour penetration and retention after rapid metabolism in hepatocytes. Our findings provide crucial insights for the development of TDO-based drug delivery systems.

Targeted SERS Imaging and Intraoperative Real-Time Elimination of Microscopic Tumors for Improved Breast-Conserving Surgery

Breast-conserving surgery is the favorable option for breast cancer patients owing to its advantages of less aggressiveness and better cosmetic outcomes over mastectomy. However, it often suffers from postsurgical lethal recurrence due to the incomplete removal of microscopic tumors. Here, a surface-enhanced Raman scattering (SERS) surgical strategy is reported for precise delineation of tumor margins and intraoperative real-time elimination of microscopic tumor foci, which is capable of complete surgical removal of breast tumors and significantly improve the outcomes of breast-conserving surgery without local tumor recurrence. The technique is chiefly based on the human epidermal growth factor receptor 2 (HER2)-targeting SERS probes with integrated multifunctionalities of ultrahigh sensitive detection, significant HER2 expression suppression, cell proliferation inhibition, and superior photothermal ablation. In a HER2+ breast tumor mouse model, the remarkable capability of the SERS surgical strategy for complete removal of HER2+ breast tumors through SERS-guided surgical resection and intraoperative real-time photothermal elimination is demonstrated. The results show complete eradiation of HER2+ breast tumors without local recurrence, consequently delivering a 100% tumor-free survival. Expectedly, this SERS surgical strategy holds great promise for clinical treatment of HER2+ breast cancer with improved patients' survival.

Nano revolution of DNA nanostructures redefining cancer therapeutics-A comprehensive review

DNA nanostructures are a promising tool in cancer treatment, offering an innovative way to improve the effectiveness of therapies. These nanostructures can be made solely from DNA or combined with other materials to overcome the limitations of traditional single-drug treatments. There is growing interest in developing nanosystems capable of delivering multiple drugs simultaneously, addressing challenges such as drug resistance. Engineered DNA nanostructures are designed to precisely deliver different drugs to specific locations, enhancing therapeutic effects. By attaching targeting molecules, these nanostructures can recognize and bind to cancer cells, increasing treatment precision. This approach offers tailored solutions for targeted drug delivery, enabling the delivery of multiple drugs in a coordinated manner. This review explores the advancements and applications of DNA nanostructures in cancer treatment, with a focus on targeted drug delivery and multi-drug therapy. It discusses the benefits and current limitations of nanoscale formulations in cancer therapy, categorizing DNA nanostructures into pure forms and hybrid versions optimized for drug delivery. Furthermore, the review examines ongoing research efforts and translational possibilities, along with challenges in clinical integration. By highlighting the advancements in DNA nanostructures, this review aims to underscore their potential in improving cancer treatment outcomes.

Superlarge, Rigidified DNA Tetrahedron with a Y-Shaped Backbone for Organizing Biomolecules Spatially and Maintaining Their Full Bioactivity

A major impediment to the clinical translation of DNA tiling nanostructures is a technical bottleneck for the programmable assembly of DNA architectures with well-defined local geometry due to the inability to achieve both sufficient structural rigidity and a large framework. In this work, a Y-backbone was inserted into each face to construct a superlarge, sufficiently rigidified tetrahedral DNA nanostructure (called RDT) with extremely high efficiency. In RDT, the spatial size increased by 6.86-fold, and the structural rigidity was enhanced at least 4-fold, contributing to an ∼350-fold improvement in the resistance to nucleolytic degradation even without a protective coating. RDT can be mounted onto an artificial lipid-bilayer membrane with molecular-level precision and well-defined spatial orientation that can be validated using the fluorescence resonance energy transfer (FRET) assay. The spatial orientation of Y-shaped backbone-rigidified RDT is unachievable for conventional DNA polyhedrons and ensures a high level of precision in the geometric positioning of diverse biomolecules with an approximately homogeneous environment. In tests of RDT, surface-confined horseradish peroxidase (HRP) exhibited nearly 100% catalytic activity and targeting aptamer-immobilized gold nanoparticles showed 5.3-fold enhanced cellular internalization. Significantly, RDT exhibited a 27.5-fold enhanced structural stability in a bodily environment and did not induce detectable systemic toxicity.

Selective inhibition of c-Met signaling pathways with a bispecific DNA nanoconnector for the targeted therapy of cancer

Hepatocyte growth factor receptor (c-Met) is a suitable molecular target for the targeted therapy of cancer. Novel c-Met-targeting drugs need to be developed because conventional small-molecule inhibitors and antibodies of c-Met have some limitations. To synthesize such drugs, we developed a bispecific DNA nanoconnector (STPA) to inhibit c-Met function. STPA was constructed by using DNA triangular prism as a scaffold and aptamers as binding molecules. After c-Met-specific SL1 and nucleolin-specific AS1411 aptamers were integrated with STPA, STPA could bind to c-Met and nucleolin on the cell membrane. This led to the formation of the c-Met/STPA/nucleolin complex, which in turn blocked c-Met activation. In vitro experiments showed that STPA could not only inhibit the c-Met signaling pathways but also facilitate c-Met degradation through lysosomes. STPA also inhibited c-Met-promoted cell migration, invasion, and proliferation. The results of in vivo experiments showed that STPA could specifically target to tumor site in xenograft mouse model, and inhibit tumor growth with low toxicity by downregulating c-Met pathways. This study provided a novel and simple strategy to develop c-Met-targeting drugs for the targeted therapy of cancer.

A Nanorobotics-Based Approach of Breast Cancer in the Nanotechnology Era

We are living in an era of advanced nanoscience and nanotechnology. Numerous nanomaterials, culminating in nanorobots, have demonstrated ingenious applications in biomedicine, including breast cancer (BC) nano-theranostics. To solve the complicated problem of BC heterogeneity, non-targeted drug distribution, invasive diagnostics or surgery, resistance to classic onco-therapies and real-time monitoring of tumors, nanorobots are designed to perform multiple tasks at a small scale, even at the organelles or molecular level. Over the last few years, most nanorobots have been bioengineered as biomimetic and biocompatible nano(bio)structures, resembling different organisms and cells, such as urchin, spider, octopus, fish, spermatozoon, flagellar bacterium or helicoidal cyanobacterium. In this review, readers will be able to deepen their knowledge of the structure, behavior and role of several types of nanorobots, among other nanomaterials, in BC theranostics. We summarized here the characteristics of many functionalized nanodevices designed to counteract the main neoplastic hallmark features of BC, from sustaining proliferation and evading anti-growth signaling and resisting programmed cell death to inducing angiogenesis, activating invasion and metastasis, preventing genomic instability, avoiding immune destruction and deregulating autophagy. Most of these nanorobots function as targeted and self-propelled smart nano-carriers or nano-drug delivery systems (nano-DDSs), enhancing the efficiency and safety of chemo-, radio- or photodynamic therapy, or the current imagistic techniques used in BC diagnosis. Most of these nanorobots have been tested in vitro, using various BC cell lines, as well as in vivo, mainly based on mice models. We are still waiting for nanorobots that are low-cost, as well as for a wider transition of these favorable effects from laboratory to clinical practice.

Engineered CpG-Loaded Nanorobots Drive Autophagy-Mediated Immunity for TLR9-Positive Cancer Therapy

Smart nanorobots have emerged as novel drug delivery platforms in nanomedicine, potentially improving anti-cancer efficacy and reducing side effects. In this study, an intelligent tumor microenvironment-responsive nanorobot is developed that effectively delivers CpG payloads to Toll-like receptor 9 (TLR9)-positive tumors to induce autophagy-mediated cell death for immunotherapy. The nanorobots are fabricated by co-self-assembly of two amphiphilic triblock polymer peptides: one containing the matrix metallopeptidase 2 (MMP2)-cleaved GPLGVRGS motif to control the mechanical opening of the nanorobots and provide targeting capability for TLR-9-positive tumors and the other consisting of an arginine-rich GRRRDRGRS sequence that can condense nuclear acid payloads through electrostatic interactions. Using multiple tumor-bearing mouse models, it is investigated whether the intravenous injection of CpG-loaded nanorobots could effectively deliver CpG payloads to TLR-9-positive tumors and elicit anti-tumor immunity through TLR9 signaling and autophagy. Therefore, besides being a commonly used adjuvant for tumor vaccination, CpG-loaded nanorobots can effectively reprogram the tumor immunosuppressive microenvironment and suppress tumor growth and recurrence. This nanorobot-based CpG immunotherapy can be considered a feasible approach to induce anti-tumor immunity, showing great therapeutic potential for the future treatment of TLR9-positive cancers.

Development of Aptamer-DNAzyme based metal-nucleic acid frameworks for gastric cancer therapy

The metal-nucleic acid nanocomposites, first termed metal-nucleic acid frameworks (MNFs) in this work, show extraordinary potential as functional nanomaterials. However, thus far, realized MNFs face limitations including harsh synthesis conditions, instability, and non-targeting. Herein, we discover that longer oligonucleotides can enhance the synthesis efficiency and stability of MNFs by increasing oligonucleotide folding and entanglement probabilities during the reaction. Besides, longer oligonucleotides provide upgraded metal ions binding conditions, facilitating MNFs to load macromolecular protein drugs at room temperature. Furthermore, longer oligonucleotides facilitate functional expansion of nucleotide sequences, enabling disease-targeted MNFs. As a proof-of-concept, we build an interferon regulatory factor-1(IRF-1) loaded Ca2+/(aptamer-deoxyribozyme) MNF to target regulate glucose transporter (GLUT-1) expression in human epidermal growth factor receptor-2 (HER-2) positive gastric cancer cells. This MNF nanodevice disrupts GSH/ROS homeostasis, suppresses DNA repair, and augments ROS-mediated DNA damage therapy, with tumor inhibition rate up to 90%. Our work signifies a significant advancement towards an era of universal MNF application.

A Multifunctional Bimetallic Nanoplatform for Synergic Local Hyperthermia and Chemotherapy Targeting HER2-Positive Breast Cancer

Anti-HER2 (human epidermal growth factor receptor 2) therapies significantly increase the overall survival of patients with HER2-positive breast cancer. Unfortunately, a large fraction of patients may develop primary or acquired resistance. Further, a multidrug combination used to prevent this in the clinic places a significant burden on patients. To address this issue, this work develops a nanotherapeutic platform that incorporates bimetallic gold-silver hollow nanoshells (AuAg HNSs) with exceptional near-infrared (NIR) absorption capability, the small-molecule tyrosine kinase inhibitor pyrotinib (PYR), and Herceptin (HCT). This platform realizes targeted delivery of multiple therapeutic effects, including chemo-and photothermal activities, oxidative stress, and immune response. In vitro assays reveal that the HCT-modified nanoparticles exhibit specific recognition ability and effective internalization by cells. The released PYR inhibit cell proliferation by downregulating HER2 and its associated pathways. NIR laser application induces a photothermal effect and tumor cell apoptosis, whereas an intracellular reactive oxygen species burst amplifies oxidative stress and triggers cancer cell ferroptosis. Importantly, this multimodal therapy also promotes the upregulation of genes related to TNF and NF-κB signaling pathways, enhancing immune activation and immunogenic cell death. In vivo studies confirm a significant reduction in tumor volume after treatment, substantiating the potential effectiveness of these nanocarriers.

Tetrahedral framework nucleic acids for improving wound healing

Wounds are one of the most common health issues, and the cost of wound care and healing has continued to increase over the past decade. In recent years, there has been growing interest in developing innovative strategies to enhance the efficacy of wound healing. Tetrahedral framework nucleic acids (tFNAs) have emerged as a promising tool for wound healing applications due to their unique structural and functional properties. Therefore, it is of great significance to summarize the applications of tFNAs for wound healing. This review article provides a comprehensive overview of the potential of tFNAs as a novel therapeutic approach for wound healing. In this review, we discuss the possible mechanisms of tFNAs in wound healing and highlight the role of tFNAs in modulating key processes involved in wound healing, such as cell proliferation and migration, angiogenesis, and tissue regeneration. The targeted delivery and controlled release capabilities of tFNAs offer advantages in terms of localized and sustained delivery of therapeutic agents to the wound site. In addition, the latest research progress on tFNAs in wound healing is systematically introduced. We also discuss the biocompatibility and biosafety of tFNAs, along with their potential applications and future directions for research. Finally, the current challenges and prospects of tFNAs are briefly discussed to promote wider applications.

Structural DNA nanotechnology at the nexus of next-generation bio-applications: challenges and perspectives

DNA nanotechnology has significantly progressed in the last four decades, creating nucleic acid structures widely used in various biological applications. The structural flexibility, programmability, and multiform customization of DNA-based nanostructures make them ideal for creating structures of all sizes and shapes and multivalent drug delivery systems. Since then, DNA nanotechnology has advanced significantly, and numerous DNA nanostructures have been used in biology and other scientific disciplines. Despite the progress made in DNA nanotechnology, challenges still need to be addressed before DNA nanostructures can be widely used in biological interfaces. We can open the door for upcoming uses of DNA nanoparticles by tackling these issues and looking into new avenues. The historical development of various DNA nanomaterials has been thoroughly examined in this review, along with the underlying theoretical underpinnings, a summary of their applications in various fields, and an examination of the current roadblocks and potential future directions.

Cell Membrane-Anchored DNA Nanoinhibitor for Inhibition of Receptor Tyrosine Kinase Signaling Pathways via Steric Hindrance and Lysosome-Induced Protein Degradation

Receptor tyrosine kinase (RTK) plays a crucial role in cancer progression, and it has been identified as a key drug target for cancer targeted therapy. Although traditional RTK-targeting drugs are effective, there are some limitations that potentially hinder the further development of RTK-targeting drugs. Therefore, it is urgently needed to develop novel, simple, and general RTK-targeting inhibitors with a new mechanism of action for cancer targeted therapy. Here, a cell membrane-anchored RTK-targeting DNA nanoinhibitor is developed to inhibit RTK function. By using a DNA tetrahedron as a framework, RTK-specific aptamers as the recognition elements, and cholesterol as anchoring molecules, this DNA nanoinhibitor could rapidly anchor on the cell membrane and specifically bind to RTK. Compared with traditional RTK-targeting inhibitors, this DNA nanoinhibitor does not need to bind at a limited domain on RTK, which increases the possibilities of developing RTK inhibitors. With the cellular-mesenchymal to epithelial transition factor (c-Met) as a target RTK, the DNA nanoinhibitor can not only induce steric hindrance effects to inhibit c-Met activation but also reduce the c-Met level via lysosome-mediated protein degradation and thus inhibition of c-Met signaling pathways and related cell behaviors. Moreover, the DNA nanoinhibitor is feasible for other RTKs by just replacing aptamers. This work may provide a novel, simple, and general RTK-targeting nanoinhibitor and possess great value in RTK-targeted cancer therapy.

Defined covalent attachment of three cancer drugs to DNA origami increases cytotoxicity at nanomolar concentration

DNA nanostructures have captured great interest as drug delivery vehicles for cancer therapy. Despite rapid progress in the field, some hurdles, such as low cellular uptake, low tissue specificity or ambiguous drug loading, remain unsolved. Herein, well-known antitumor drugs (doxorubicin, auristatin, and floxuridine) were site-specifically incorporated into DNA nanostructures, demonstrating the potential advantages of covalently linking drug molecules via structural staples instead of incorporating the drugs by noncovalent binding interactions. The covalent strategy avoids critical issues such as an unknown number of drug-DNA binding events and premature drug release. Moreover, covalently modified origami offers the possibility of precisely incorporating several synergetic antitumor drugs into the DNA nanostructure at a predefined molar ratio and to control the exact spatial orientation of drugs into DNA origami. Additionally, DNA-based nanoscaffolds have been reported to have a low intracellular uptake. Thus, two cellular uptake enhancing mechanisms were studied: the introduction of folate units covalently linked to DNA origami and the transfection of DNA origami with Lipofectamine. Importantly, both methods increased the internalization of DNA origami into HTB38 and HCC2998 colorectal cancer cells and produced greater cytotoxic activity when the DNA origami incorporated antiproliferative drugs. The results here present a successful and conceptually distinct approach for the development of DNA-based nanostructures as drug delivery vehicles, which can be considered an important step towards the development of highly precise nanomedicines.

Aptamer-based targeted delivery systems for cancer treatment using DNA origami and DNA nanostructures

Due to the limitations of conventional cancer treatment methods, nanomedicine has appeared as a promising alternative, allowing improved drug targeting and decreased drug toxicity. In the development of cancer nanomedicines, among various nanoparticles (NPs), DNA nanostructures are more attractive because of their precisely controllable size, shape, excellent biocompatibility, programmability, biodegradability, and facile functionalization. Aptamers are introduced as single-stranded RNA or DNA molecules with recognize their corresponding targets. So, incorporating aptamers into DNA nanostructures led to influential vehicles for bioimaging and biosensing as well as targeted cancer therapy. In this review, the recent developments in the application of aptamer-based DNA origami and DNA nanostructures in advanced cancer treatment have been highlighted. Some of the main methods of cancer treatment are classified as chemo-, gene-, photodynamic- and combined therapy. Finally, the opportunities and problems for targeted DNA aptamer-based nanocarriers for medicinal applications have also been discussed.

3D DNAzyme walker based electrochemical biosensor for attomolar level microRNA-155 detection

Herein, an ultrasensitive electrochemical biosensor for microRNA-155 (miR-155) detection based on the powerful catalytic and continuous walking signal amplification capability of 3D DNAzyme walker and the gold nanoparticles/graphene aerogels carbon fiber paper-based (AuNPs/GAs/CFP) flexible sensing electrode with excellent electrochemical performance was successfully constructed. In a proof-of-concept experiment, in the presence of miR-155, the DNAzyme strands anchored on the streptavidin-modified magnetic beads (MBs) silenced by locked strands can be activated, thus generating the walking arm of the 3D DNAzyme walker. Meanwhile, the substrate strands modified with Fe-MOF-NH2 nanoparticles were evenly distributed on the surface of MBs and served as tracks of the 3D DNAzyme walker. Once the DNAzyme strand was activated, the catalytic site in the substrate strand can be cleaved in the presence of Mn2+, and a large number of stumps modified with Fe-MOF-NH2 nanoparticles (output@Fe-MOF-NH2) will be generated during the continuous and efficient walking cleavage of the DNAzyme walker, driving the recognition-catalysis-release cycle process for signal amplification. Immediately afterwards, the signal was read out through the base complementary pairing of capture probe (PS) immobilized on the surface of the paper-based flexible sensing electrode AuNPs/GAs/CFP and signal probes output@Fe-MOF-NH2, thus achieving the quantitative detection of miR-155. Under optimal experimental conditions, the designed 3D DNAzyme walker-based biosensor exhibited a relatively lower limit of detection (LOD) of 56.23 aM, with a linear range of 100 aM to 100 nM. Overall, the proposed 3D DNAzyme walker biosensor exhibited good interference and reproducibility, demonstrating a promising future in the field of clinical disease diagnosis.

Biomembrane‐inspired design of medical micro/nanorobots: From cytomembrane stealth cloaks to cellularized Trojan horses

Micro/nanorobots are promising for a wide range of biomedical applications (such as targeted tumor, thrombus, and infection therapies in hard‐to‐reach body sites) because of their tiny size and high maneuverability through the actuation of external fields (e.g., magnetic field, light, ultrasound, electric field, and/or heat). However, fully synthetic micro/nanorobots as foreign objects are susceptible to phagocytosis and clearance by diverse phagocytes. To address this issue, researchers have attempted to develop various cytomembrane‐camouflaged micro/nanorobots by two means: (1) direct coating of micro/nanorobots with cytomembranes derived from living cells and (2) the swallowing of micro/nanorobots by living immunocytes via phagocytosis. The camouflaging with cytomembranes or living immunocytes not only protects micro/nanorobots from phagocytosis, but also endows them with new characteristics or functionalities, such as prolonging propulsion in biofluids, targeting diseased areas, or neutralizing bacterial toxins. In this review, we comprehensively summarize the recent advances and developments of cytomembrane‐camouflaged medical micro/nanorobots. We first discuss how cytomembrane coating nanotechnology has been employed to engineer synthetic nanomaterials, and then we review in detail how cytomembrane camouflage tactic can be exploited to functionalize micro/nanorobots. We aim to bridge the gap between cytomembrane‐cloaked micro/nanorobots and nanomaterials and to provide design guidance for developing cytomembrane‐camouflaged micro/nanorobots.

Self-Assembled Multivalent Aptamer Drug Conjugates: Enhanced Targeting and Cytotoxicity for HER2-Positive Gastric Cancer

Antibody drug conjugates (ADCs) have shown promise to be the mainstream chemotherapeutics for advanced HER2-positive cancers, yet the issues of poor drug delivery efficiency, limited chemotherapeutic effects, severe immune responses, and drug resistance remain to be addressed before the clinical applications of ADCs. The DNA aptamer-guided drug conjugates (ApDCs) are receiving growing attention for specific tumors due to their excellent tumor affinity and low cost. Therefore, developing a multivalent ApDC nanomedicine by combining anti-HER2 aptamer (HApt), tetrahedral framework nucleic acid (tFNA), and deruxtecan (Dxd) together to form HApt-tFNA@Dxd might help to address these concerns. In this study, the HER2-targeted DNA aptamer modified DNA tetrahedron (HApt-tFNA) was employed as a system for drug delivery, and the adoption of tFNA could effectively enlarge the drug-loading rate compared to aptamer-guided ApDCs previously reported. Compared with free Dxd and tFNA@Dxd, HApt-tFNA@Dxd showed better structural stability, excellent targeted cytotoxicity to HER2-positive gastric cancer, and increased tissue aggregation ability in tumors. These features and superiorities make HApt-tFNA@Dxd a promising chemotherapeutic medicine for HER2-positive tumors. Our work developed a new targeting nanomedicine by combining DNA nanomaterials and chemotherapeutic agents, which represents a critical advance toward developing novel DNA-based nanomaterials and promoting their potential applications for HER2-positive cancer therapy.

Application and prospects of nucleic acid nanomaterials in tumor therapy

Cancer poses a great threat to human life, and current cancer treatments, such as radiotherapy, chemotherapy, and surgery, have significant side effects and limitations that hinder their application. Nucleic acid nanomaterials have specific spatial configurations and can be used as nanocarriers to deliver different therapeutic drugs, thereby enabling various biomedical applications, such as biosensors and cancer therapy. In recent decades, a variety of DNA nanostructures have been synthesized, and they have demonstrated remarkable potential in cancer therapy related applications, such as DNA origami structures, tetrahedral framework nucleic acids, and dynamic DNA nanostructures. Importantly, more attention is also being paid to RNA nanostructures, which play an important role in gene therapy. Therefore, this review introduces the developmental history of nucleic acid nanotechnology, summarizes the applications of DNA and RNA nanostructures for tumor treatment, and discusses the development opportunities for nucleic acid nanomaterials in the future.

Advances of medical nanorobots for future cancer treatments

Early detection and diagnosis of many cancers is very challenging. Late stage detection of a cancer always leads to high mortality rates. It is imperative to develop novel and more sensitive and effective diagnosis and therapeutic methods for cancer treatments. The development of new cancer treatments has become a crucial aspect of medical advancements. Nanobots, as one of the most promising applications of nanomedicines, are at the forefront of multidisciplinary research. With the progress of nanotechnology, nanobots enable the assembly and deployment of functional molecular/nanosized machines and are increasingly being utilized in cancer diagnosis and therapeutic treatment. In recent years, various practical applications of nanobots for cancer treatments have transitioned from theory to practice, from in vitro experiments to in vivo applications. In this paper, we review and analyze the recent advancements of nanobots in cancer treatments, with a particular emphasis on their key fundamental features and their applications in drug delivery, tumor sensing and diagnosis, targeted therapy, minimally invasive surgery, and other comprehensive treatments. At the same time, we discuss the challenges and the potential research opportunities for nanobots in revolutionizing cancer treatments. In the future, medical nanobots are expected to become more sophisticated and capable of performing multiple medical functions and tasks, ultimately becoming true nanosubmarines in the bloodstream.

The Current Progress of Tetrahedral DNA Nanostructure for Antibacterial Application and Bone Tissue Regeneration

Recently, programmable assembly technologies have enabled the application of DNA in the creation of new nanomaterials with unprecedented functionality. One of the most common DNA nanostructures is the tetrahedral DNA nanostructure (TDN), which has attracted great interest worldwide due to its high stability, simple assembly procedure, high predictability, perfect programmability, and excellent biocompatibility. The unique spatial structure of TDN allows it to penetrate cell membranes in abundance and regulate cellular biological properties as a natural genetic material. Previous studies have demonstrated that TDNs can regulate various cellular biological properties, including promoting cells proliferation, migration and differentiation, inhibiting cells apoptosis, as well as possessing anti-inflammation and immunomodulatory capabilities. Furthermore, functional molecules can be easily modified at the vertices of DNA tetrahedron, DNA double helix structure, DNA tetrahedral arms or DNA tetrahedral cage structure, enabling TDN to be used as a nanocarrier for a variety of biological applications, including targeted therapies, molecular diagnosis, biosensing, antibacterial treatment, antitumor strategies, and tissue regeneration. In this review, we mainly focus on the current progress of TDN-based nanomaterials for antimicrobial applications, bone and cartilage tissue repair and regeneration. The synthesis and characterization of TDN, as well as the biological merits are introduced. In addition, the challenges and prospects of TDN-based nanomaterials are also discussed.

Recent progress and application of the tetrahedral framework nucleic acid materials on drug delivery

INTRODUCTION

The application of DNA framework nucleic acid materials in the biomedical field has witnessed continual expansion. Among them, tetrahedral framework nucleic acids (tFNAs) have gained significant traction as the foremost biological vectors due to their superior attributes of editability, low immunogenicity, biocompatibility, and biodegradability. tFNAs have demonstrated promising results in numerous in vitro and in vivo applications.

AREAS COVERED

This review summarizes the latest research on tFNAs in drug delivery, including a discussion of the advantages of tFNAs in regulating biological behaviors, and highlights the updated development and advantageous applications of tFNAs-based nanostructures from static design to dynamically responsive design.

EXPERT OPINION

tFNAs possess distinct biological regulatory attributes and can be taken up by cells without the requirement of transfection, differentiating them from other biological vectors. tFNAs can be easily physically/chemically modified and seamlessly incorporated with other functional systems. The static design of the tFNAs-based drug delivery system makes it versatile, reproducible, and predictable. Further use of the dynamic response mechanism of DNA to external stimuli makes tFNAs-based drug delivery more effective and specific, improving the uptake and utilization of the payload by the intended target. Dynamic targeting is poised to become the future primary approach for drug delivery.

DNA-directed assembly of nanomaterials and their biomedical applications

In the past decades, DNA has been widely used in the field of nanostructures due to its unique programmable properties. Besides being used to form its own diverse structures such as the assembly of DNA origami, DNA can also be used for the assembly of nanostructures with other materials. In this review, different strategies for the functionalization of DNA on nanoparticle surfaces are listed, and the roles of DNA in the assembly of nanostructures as well as the influencing factors are discussed. Finally, the biomedical applications of DNA-assembled nanostructures were summarized. This review provided new insight into the application of DNA in nanostructure assembly.

Functionalized liposomes for targeted breast cancer drug delivery

Despite the exceptional progress in breast cancer pathogenesis, prognosis, diagnosis, and treatment strategies, it remains a prominent cause of female mortality worldwide. Additionally, although chemotherapies are effective, they are associated with critical limitations, most notably their lack of specificity resulting in systemic toxicity and the eventual development of multi-drug resistance (MDR) cancer cells. Liposomes have proven to be an invaluable drug delivery system but of the multitudes of liposomal systems developed every year only a few have been approved for clinical use, none of which employ active targeting. In this review, we summarize the most recent strategies in development for actively targeted liposomal drug delivery systems for surface, transmembrane and internal cell receptors, enzymes, direct cell targeting and dual-targeting of breast cancer and breast cancer-associated cells, e.g., cancer stem cells, cells associated with the tumor microenvironment, etc.

DNA-Based Nanomaterials as Drug Delivery Platforms for Increasing the Effect of Drugs in Tumors

DNA nanotechnology has significantly advanced and might be used in biomedical applications, drug delivery, and cancer treatment during the past few decades. DNA nanomaterials are widely used in biomedical research involving biosensing, bioimaging, and drug delivery since they are remarkably addressable and biocompatible. Gradually, modified nucleic acids have begun to be employed to construct multifunctional DNA nanostructures with a variety of architectural designs. Aptamers are single-stranded nucleic acids (both DNAs and RNAs) capable of self-pairing to acquire secondary structure and of specifically binding with the target. Diagnosis and tumor therapy are prospective fields in which aptamers can be applied. Many DNA nanomaterials with three-dimensional structures have been studied as drug delivery systems for different anticancer medications or gene therapy agents. Different chemical alterations can be employed to construct a wide range of modified DNA nanostructures. Chemically altered DNA-based nanomaterials are useful for drug delivery because of their improved stability and inclusion of functional groups. In this work, the most common oligonucleotide nanomaterials were reviewed as modern drug delivery systems in tumor cells.

Nanoconstructs for theranostic application in cancer: Challenges and strategies to enhance the delivery

Nanoconstructs are made up of nanoparticles and ligands, which can deliver the loaded cargo at the desired site of action. Various nanoparticulate platforms have been utilized for the preparation of nanoconstructs, which may serve both diagnostic as well as therapeutic purposes. Nanoconstructs are mostly used to overcome the limitations of cancer therapies, such as toxicity, nonspecific distribution of the drug, and uncontrolled release rate. The strategies employed during the design of nanoconstructs help improve the efficiency and specificity of loaded theranostic agents and make them a successful approach for cancer therapy. Nanoconstructs are designed with a sole purpose of targeting the requisite site, overcoming the barriers which hinders its right placement for desired benefit. Therefore, instead of classifying modes for delivery of nanoconstructs as actively or passively targeted systems, they are suitably classified as autonomous and nonautonomous types. At large, nanoconstructs offer numerous benefits, however they suffer from multiple challenges, too. Hence, to overcome such challenges computational modelling methods and artificial intelligence/machine learning processes are being explored. The current review provides an overview on attributes and applications offered by nanoconstructs as theranostic agent in cancer.

A Review of Advanced Multifunctional Magnetic Nanostructures for Cancer Diagnosis and Therapy Integrated into an Artificial Intelligence Approach

The new era of nanomedicine offers significant opportunities for cancer diagnostics and treatment. Magnetic nanoplatforms could be highly effective tools for cancer diagnosis and treatment in the future. Due to their tunable morphologies and superior properties, multifunctional magnetic nanomaterials and their hybrid nanostructures can be designed as specific carriers of drugs, imaging agents, and magnetic theranostics. Multifunctional magnetic nanostructures are promising theranostic agents due to their ability to diagnose and combine therapies. This review provides a comprehensive overview of the development of advanced multifunctional magnetic nanostructures combining magnetic and optical properties, providing photoresponsive magnetic platforms for promising medical applications. Moreover, this review discusses various innovative developments using multifunctional magnetic nanostructures, including drug delivery, cancer treatment, tumor-specific ligands that deliver chemotherapeutics or hormonal agents, magnetic resonance imaging, and tissue engineering. Additionally, artificial intelligence (AI) can be used to optimize material properties in cancer diagnosis and treatment, based on predicted interactions with drugs, cell membranes, vasculature, biological fluid, and the immune system to enhance the effectiveness of therapeutic agents. Furthermore, this review provides an overview of AI approaches used to assess the practical utility of multifunctional magnetic nanostructures for cancer diagnosis and treatment. Finally, the review presents the current knowledge and perspectives on hybrid magnetic systems as cancer treatment tools with AI models.

Self-assembly of DNA nanospheres with controllable size and self-degradable property for enhanced antitumor chemotherapy

Controllable size, self-degradability and targeting property are important for a precise improvement of anticancer effects and reduction of side effects of drug vehicles. Here, a series of DNA nanospheres with controllable size and self-degradation ability were constructed through the hybridization of two i-motif strands and two linker strands for targeted cancer therapy. DNA nanospheres with different sizes were fabricated by regulating the linker sequence, and their pH-responsive self-degradation property was realized by the introduction of the i-motif strand. Moreover, the ZY11 aptamer was introduced to endow the DNA nanospheres with targeting property toward SMMC-7721 cancer cells. The results revealed that the appropriate size of DNA nanospheres (80 nm) highly promoted the internalization by mammalian cells. The results of DLS, AFM and CD spectra showed that the DNA nanospheres were stable in a physiological environment but they self-degraded in a slightly acidic environment due to the existence of the i-motif strand. Moreover, the fluorescence of DOX@AP-NSs2 was triple at pH = 5.0 than at pH = 7.4, which further confirmed the pH-responsive drug release performance. The above results proved that the use of DOX@AP-NSs2 is a promising approach to accelerate the rapid release of drugs into the tumors and avoid drug leakage into the normal tissue. The results at a cellular level and in vivo confirmed the pH-responsive targeted antitumor effect. Hence, the novel DNA nanospheres with controllable size and self-degradable property represent a potential tool for targeted drug delivery and cancer therapy.

A dynamic DNA tetrahedron framework for active targeting

An active targeting strategy-enabled DNA tetrahedron delivery vehicle could facilitate stable drug encapsulation and stimuli-responsive on-demand release, building a universal platform for different drug delivery requirements. Owing to the excellent biocompatible nature, programmability and remarkable cell and tissue permeability, the tetrahedral DNA nanostructure (TDN) has proven its value in the delivery of various bioactive molecules. We previously described this as a static multifunctional complex in our earlier protocol. However, static structures and passive targeting behavior might introduce off-target effects under complicated biological conditions. Therefore, in this Protocol Extension, we present a major update of the TDN delivery vehicle enabling an active targeting strategy to be used for stimuli-sensitive conformation changes and on-site cargo release, which could avoid drawbacks, including complex and time-consuming fabrication processes and undetermined cell penetration ability of other DNA-based delivery vehicles. Upon exquisite design of TDN size based on cargo type, one-pot annealing is applied to fabricate the Tiamat-designed TDN exoskeleton. Then the design of the dynamic DNA apparatus can be based on the target and environmental stimuli, including DNA strand hybridization-based and pH-sensitive DNA apparatus, and careful titration of strand lengths and mismatches is achieved using polyacrylamide and agarose gel electrophoresis, or fluorophore modifications. Finally, cargo loading strategies are designed, including site and stand titration and cargo encapsulation verification. The dynamic structures show promising targetability and effectiveness in antitumor and anti-inflammatory treatment in vitro and in vivo. Assembly and characterization in the lab takes ~5 d, and the timing for the verification of biostability and biological applications depends on the uses.

DNA Origami: Recent Progress and Applications

This chapter explores the basic concept of DNA origami and its various types. By showing the progress made in structural DNA nanotechnology during the last 15 years, the chapter draws attention to the capability of DNA origami to construct complex structures in both 2D and 3D level. As well as looking at a few examples of dynamic DNA nanostructures, the chapter also explores the possible applications of DNA origami in different fields, such as biological computing, nanorobotics, and DNA walkers.

DNA-Tetrahedra Corona-Modified Hydrogel Microcapsules: "Smart" ATP- or microRNA-Responsive Drug Carriers

The assembly of adenosine triphosphate (ATP)-responsive and miRNA-responsive DNA tetrahedra-functionalized carboxymethyl cellulose hydrogel microcapsules is presented. The microcapsules are loaded with the doxorubicin-dextran drug or with CdSe/ZnS quantum dots as a drug model. Selective unlocking of the respective microcapsules and the release of the loads in the presence of ATP or miRNA-141 are demonstrated. Functionalization of the hydrogel microcapsules a with corona of DNA tetrahedra nanostructures yields microcarriers that revealed superior permeation into cells. This is demonstrated by the effective permeation of the DNA tetrahedra-functionalized microcapsules into MDA-MB-231 breast cancer cells, as compared to epithelial MCF-10A nonmalignant breast cells. The superior permeation of the tetrahedra-functionalized microcapsules into MDA-MB-231 breast cancer cells, as compared to analog control hydrogel microcapsules modified with a corona of nucleic acid duplexes. The effective permeation of the stimuli-responsive, drug-loaded, DNA tetrahedra-modified microcapsules yields drug carriers of superior and selective cytotoxicity toward cancer cells.

Could artificial intelligence revolutionize the development of nanovectors for gene therapy and mRNA vaccines?

Gene therapy enables the introduction of nucleic acids like DNA and RNA into host cells, and is expected to revolutionize the treatment of a wide range of diseases. This growth has been further accelerated by the discovery of CRISPR/Cas technology, which allows accurate genomic editing in a broad range of cells and organisms in vitro and in vivo. Despite many advances in gene delivery and the development of various viral and non-viral gene delivery vectors, the lack of highly efficient non-viral systems with low cellular toxicity remains a challenge. The application of cutting-edge technologies such as artificial intelligence (AI) has great potential to find new paradigms to solve this issue. Herein, we review AI and its major subfields including machine learning (ML), neural networks (NNs), expert systems, deep learning (DL), computer vision and robotics. We discuss the potential of AI-based models and algorithms in the design of targeted gene delivery vehicles capable of crossing extracellular and intracellular barriers by viral mimicry strategies. We finally discuss the role of AI in improving the function of CRISPR/Cas systems, developing novel nanobots, and mRNA vaccine carriers.

Self-assembly of DNA nanostructure containing cell-specific aptamer as a precise drug delivery system for cancer therapy in non-small cell lung cancer

Background

As the most common subtype in lung cancer, the precise and efficient treatment for non-small cell lung cancer (NSCLC) remains an outstanding challenge owing to early metastasis and poor prognosis. Chemotherapy, the most commonly used treatment modality, is a difficult choice for many cancer patients due to insufficient drug accumulation in tumor sites and severe systemic side-effects. In this study, we constructed a cell-specific aptamer-modified DNA nanostructure (Apt-NS) as a targeting drug delivery system achieving the precision therapy for lung cancer.

Methods

The synthesis of DNA nanostructure and its stability were evaluated using gel electrophoresis. The targeting properties and internalization mechanism were investigated via flow cytometry and confocal analyses. Drug loading, release, and targeted drug delivery were determined by fluorescence detection, Zeta potentials assay, and confocal imaging. CCK8 assays, colony formation, cell apoptosis, metastasis analyses and in vivo experiments were conducted to assess the biological functions of DNA nanostructure.

Results

Self-assembled DNA nanoparticles (Apt-NS) had excellent stability to serum and DNase I and the ability to specifically recognize A549 cells. Upon specific binding, the drug-loaded nanoparticles (Apt-NS-DOX) were internalized into target cells by clathrin-mediated endocytosis. Subsequently, DOX could be released from Apt-NS-DOX based on the degradation of the lysosome. Apt-NS-DOX exerted significant suppression of cell proliferation, invasion and migration, and also enhanced cell apoptosis due to the excellent performance of drug delivery and intracellular release, while maintaining a superior biosafety. In addition, the antitumor effects of Apt-NS-DOX were further confirmed using in vivo models.

Conclusions

Our study provided cell-specific aptamer-modified DNA nanostructures as a drug-delivery system targeting A549 cells, which could precisely and efficiently transport chemotherapeutic drug into tumor cells, exerting enhanced antineoplastic efficacy. These findings highlight that DNA nanostructure serving as an ideal drug delivery system in cancer treatment appears great promise in biomedical applications.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12951-022-01701-5.

Outward Movement of Targeting Ligands from a Built-In Reserve Pool in Nuclease-Resistant 3D Hierarchical DNA Nanocluster for in Vivo High-Precision Cancer Therapy

Nanostructures made entirely of DNAs display great potential as chemotherapeutic drug carriers but so far cannot achieve sufficient clinic therapy outcomes due to off-target toxicity. In this contribution, an aptamer-embedded hierarchical DNA nanocluster (Apt-eNC) is constructed as an intelligent carrier for cancer-targeted drug delivery. Specifically, Apt-eNC is designed to have a built-in reserve pool in the interior cavity from which aptamers may move outward to function as needed. When surface aptamers are degraded, ones in reserve pool can move outward to offer the compensation, thereby magically preserving tumor-targeting performance in vivo. Even if withstanding extensive aptamer depletion, Apt-eNC displays a 115-fold enhanced cell targeting compared with traditional counterparts and at least 60-fold improved tumor accumulation. Moreover, one Apt-eNC accommodates 5670 chemotherapeutic agents. As such, when systemically administrated into HeLa tumor-bearing BALB/c nude mouse model, drug-loaded Apt-eNC significantly inhibits tumor growth without systemic toxicity, holding great promise for high precision therapy.

Advances in regenerative medicine applications of tetrahedral framework nucleic acid-based nanomaterials: an expert consensus recommendation

With the emergence of DNA nanotechnology in the 1980s, self-assembled DNA nanostructures have attracted considerable attention worldwide due to their inherent biocompatibility, unsurpassed programmability, and versatile functions. Especially promising nanostructures are tetrahedral framework nucleic acids (tFNAs), first proposed by Turberfield with the use of a one-step annealing approach. Benefiting from their various merits, such as simple synthesis, high reproducibility, structural stability, cellular internalization, tissue permeability, and editable functionality, tFNAs have been widely applied in the biomedical field as three-dimensional DNA nanomaterials. Surprisingly, tFNAs exhibit positive effects on cellular biological behaviors and tissue regeneration, which may be used to treat inflammatory and degenerative diseases. According to their intended application and carrying capacity, tFNAs could carry functional nucleic acids or therapeutic molecules through extended sequences, sticky-end hybridization, intercalation, and encapsulation based on the Watson and Crick principle. Additionally, dynamic tFNAs also have potential applications in controlled and targeted therapies. This review summarized the latest progress in pure/modified/dynamic tFNAs and demonstrated their regenerative medicine applications. These applications include promoting the regeneration of the bone, cartilage, nerve, skin, vasculature, or muscle and treating diseases such as bone defects, neurological disorders, joint-related inflammatory diseases, periodontitis, and immune diseases.

Endogenous Stimuli-Responsive Autonomous Separation of Dual-Targeting DNA Guided Missile from Nanospacecraft for Intelligent Targeted Cancer Therapy

Most conventional chemotherapeutics indiscriminately kill both cancerous and healthy cells and cause toxic side effects, limiting the maximum tolerated dose and thereby compromising therapeutic efficacy. To address this challenge, here dual-targeting intelligent DNA guided missile (GM)-integrated nanospacecraft (NSC) (abbreviated as GM-NSC) is demonstrated for staged chemotherapeutic drug delivery exclusively into cancer cells and then mitochondria (not into healthy cells). GM-NSC is essentially a core/shell nanocomposite composed of gold nanoparticles (AuNPs) surrounded by a high-density multilayer DNA crown that is self-assembled from DNA tetrahedral units (DNA Tetra) in a highly ordered manner. Each tetrahedral structural unit is equipped with three functional components: a cancer cell-targeting aptamer pointing toward the outside environment, a hidden mitochondria-targeting triphenylphosphonium (TPP), and an explosive bolt (E-bolt). GM-NSC can remain intact in fetal bovine serum solution over 12 h and has 53-fold improved systemic stability. Each GM-NSC accommodates 1250 anticancer doxorubicin (Dox), achieving a 48-63-fold improved drug payload capacity. When systemically administrated into a tumor-bearing xenograft murine model, Dox-loaded GM-NSC enters into tumor sites with 18-fold improved specificity followed by autonomous separation of GMs from the NSC core and specific mitochondrial accumulation due to the explosion of E-bolt upon stimuli of endogenous miRNAs. About 80% of Dox uptaken is transferred into mitochondria and induces mitochondria-mediated apoptosis. As a result, the growth of malignant tumor is almost 100% inhibited without detectable toxicity to healthy tissues. Due to the desirable systemic stability, good biocompatibility, high cargo loading capability, satisfactory in vivo biodistribution, and therapeutic efficacy without adverse effects, intelligible GM-NSC is expected to become an alternative drug delivery system for precision cancer therapy.

BACE1 Aptamer-Modified Tetrahedral Framework Nucleic Acid to Treat Alzheimer's Disease in an APP-PS1 Animal Model

Alzheimer's disease is a neurodegenerative disease caused by excessive amyloid β protein-induced neurotoxicity. However, drugs targeting amyloid β protein production face many problems, such as the low utilization rate of drugs by cells and the difficulty of drugs in penetrating the blood-brain barrier. A tetrahedral framework nucleic acid is a new type of nanonucleic acid structure that functions as a therapy and drug carrier. Here, we synthesized a BACE1 aptamer-modified tetrahedral framework nucleic acid and tested its therapeutic effect on Alzheimer's disease in vitro and in vivo. Our results demonstrated that the tetrahedral framework nucleic acid could be used as a carrier to deliver the BACE1 aptamer to the brain to reduce the production of amyloid β proteins. It also played an antiapoptotic role by reducing the production of reactive oxygen species. Thus, this nanomaterial is a potential drug for Alzheimer's disease.

An intelligent DNA nanorobot for detection of MiRNAs cancer biomarkers using molecular programming to fabricate a logic-responsive hybrid nanostructure

Herein, we designed a DNA framework-based intelligent nanorobot using toehold-mediated strand displacement reaction-based molecular programming and logic gate operation for the selective and synchronous detection of miR21 and miR125b, which are known as significant cancer biomarkers. Moreover, to investigate the applicability of our design, DNA nanorobots were implemented as capping agents onto the pores of MSNs. These agents can develop a logic-responsive hybrid nanostructure capable of specific drug release in the presence of both targets. The prosperous synthesis steps were verified by FTIR, XRD, BET, UV-visible, FESEM-EDX mapping, and HRTEM analyses. Finally, the proper release of the drug in the presence of both target microRNAs was studied. This Hybrid DNA Nanostructure was designed with the possibility to respond to any target oligonucleotides with 22 nucleotides length.

Functionalized-DNA nanostructures as potential targeted drug delivery systems for cancer therapy

Seeman's pioneer idea has led to the foundation of DNA nanostructures, resulting in a remarkable advancement in DNA nanotechnology. Over the last few decades, remarkable advances in drug delivery techniques have resulted in the self-assembly of DNA for encapsulating candidate drug molecules. The nuclear targeting capability of DNA nanostructures is lies within their high spatial addressability and tremendous potential for active targeting. However, effective programming and assembling those DNA molecules remains a challenge, making the path to DNA nanostructures for real-world applications difficult. Because of their small size, most nanostructures are self-capable of infiltrating into the tumor cellular environment. Furthermore, to enable controlled and site-specific delivery of encapsulated drug molecules, DNA nanostructures are functionalized with special moieties that allow them to bind specific targets and release cargo only at targeted sites rather than non-specific sites, resulting in the prevention/limitation of cellular toxicity. In light of this, the current review seeks to shed light on the versatility of the DNA molecule as a targeting and encapsulating moiety for active drugs in order to achieve controlled and specific drug release with spatial and temporal precision. Furthermore, this review focused on the challenges associated with the construction of DNA nanostructures as well as the most recent advances in the functionalization of DNA nanostructures using various materials for controlled and targeted delivery of medications for cancer therapy.

Label-Free Plasmon-Enhanced Spectroscopic HER2 Detection for Dynamic Therapeutic Surveillance of Breast Cancer

The expression of human epidermal growth factor receptor-2 (HER2) has important implications for pathogenesis, progression, and therapeutic efficacy of breast cancer. The detection of its variation during the treatment is crucial for therapeutic decision-making but remains a grand challenge, especially at the cellular level. Here, we develop a machine learning-driven surface-enhanced Raman spectroscopy (SERS)-integrated strategy for label-free detection of cellular HER2. Specifically, our method allows the extraction of cell-rich spectral signatures utilized for identification and classification of cancer cells with distinct HER2 expression with a high accuracy of 99.6%. By combining label-free SERS detection and machine learning-driven chemometric analysis, we are able to perform longitudinal monitoring of therapeutic efficacy at the cellular level during the treatment of HER2+ breast cancer, which aids in the subsequent decision-making and management. This work provides a promising technique capable of performing dynamic label-free spectroscopic detection for therapeutic surveillance of diseases.