Nanoscale ATP-Responsive Zeolitic Imidazole Framework-90 as a General Platform for Cytosolic Protein Delivery and Genome Editing

Rational design of diblock copolymer enables efficient cytosolic protein delivery

Polymer-mediated cytosolic protein delivery demonstrates a promising strategy for the development of protein therapeutics. Here, we propose a new designed diblock copolymer which realizes efficient cytosolic protein delivery both in vitro and in vivo. The polymer contains one protein-binding block composed of phenylboronic acid (PBA) and N-(3-dimethylaminopropyl) (DMAP) pendant units for protein binding and endosomal escape, respectively, followed by the response to ATP enriched in the cytosol which triggers the protein release. The other block is PEG designed to improve particle size control and circulation in vivo. By optimizing the block composition, sequence and length of the copolymer, the optimal one (BP20) was identified with the binding block containing 20 units of both PBA and DMAP, randomly distributed along the chain. When mixed with proteins, the BP20 forms stable nanoparticles and mediates efficient cytosolic delivery of a wide range of proteins including enzymes, toxic proteins and CRISPR/Cas9 ribonucleoproteins (RNP), to various cell lines. The PEG block, especially when further modified with folic acid (FA), enables tumor-targeted delivery of Saporin in vivo, which significantly suppresses the tumor growth. Our results shall inspire the design of novel polymeric vehicles with robust capability for cytosolic protein delivery, which holds great potential for both biological research and therapeutic applications.

Research Progress of Metal-Organic Frameworks as Drug Delivery Systems

Metal-organic frameworks (MOFs) are composite crystalline materials created through the coordination of metal ions and organic ligands. MOFs have attracted extensive attention in the biomedical field based on the advantages of internal porosity, customizable porosity, and facile surface modification. This review examines the utilization of MOFs in drug delivery systems, focusing on the research progress from the aspects of coloading drug systems, intelligent responsive carriers, biological macromolecule stabilizers, self-driving micro/nanomotors, and multifunctional living carriers. In addition, the current challenges the research faces are also discussed. The review aims to provide a reference for the further application of MOFs as advanced drug delivery systems.

A Nanozyme-Boosted MOF-CRISPR Platform for Treatment of Alzheimer's Disease

Rectifying the aberrant microenvironment of a disease through maintenance of redox homeostasis has emerged as a promising perspective with significant therapeutic potential for Alzheimer's disease (AD). Herein, we design and construct a novel nanozyme-boosted MOF-CRISPR platform (CMOPKP), which can maintain redox homeostasis and rescue the impaired microenvironment of AD. By modifying the targeted peptides KLVFFAED, CMOPKP can traverse the blood-brain barrier and deliver the CRISPR activation system for precise activation of the Nrf2 signaling pathway and downstream redox proteins in regions characterized by oxidative stress, thereby reinstating neuronal antioxidant capacity and preserving redox homeostasis. Furthermore, cerium dioxide possessing catalase enzyme-like activity can synergistically alleviate oxidative stress. Further in vivo studies demonstrate that CMOPKP can effectively alleviate cognitive impairment in 3xTg-AD mouse models. Therefore, our design presents an effective way for regulating redox homeostasis in AD, which shows promise as a therapeutic strategy for mitigating oxidative stress in AD.

Tumor Microenvironment Responsive RNA Drug Delivery Systems: Intelligent Platforms for Sophisticated Release

Cancer is a significant health concern, increasingly showing insensitivity to traditional treatments, highlighting the urgent need for safer and more practical treatment options. Ribonucleic acid (RNA) gene therapy drugs have demonstrated promising potential in preclinical and clinical trials for antitumor therapy by regulating tumor-related gene expression. However, RNA's poor membrane permeability and stability restrict its effectiveness in entering and being utilized in cells. An appropriate delivery system is crucial for achieving targeted tumor effects. The tumor microenvironment (TME), characterized by acidity, hypoxia, enzyme overexpression, elevated glutathione (GSH) concentration, and excessive reactive oxygen species (ROS), is essential for tumor survival. Furthermore, these distinctive features can also be harnessed to develop intelligent drug delivery systems. Various nanocarriers that respond to the TME have been designed for RNA drug delivery, showing the advantages of tumor targeting and low toxicity. This Review discusses the abnormal changes of components in TME, therapeutic RNAs' roles, underlying mechanisms, and the latest developments in utilizing vectors that respond to microenvironments for treating tumors. We hope it provides insight into creating and optimizing RNA delivery vectors to improve their effectiveness.

Integrated design and application of stimuli-responsive metal-organic frameworks in biomedicine: current status and future perspectives

In recent years, metal-organic frameworks (MOFs) have garnered widespread attention due to their distinctive attributes, such as high surface area, tunable properties, biodegradability, extremely low density, high loading capacity, diverse chemical functionalities, thermal stability, well-defined pore sizes, and molecular dimensions. Increasingly, biomedical researchers have turned their focus towards their multifaceted development. Among these, stimuli-responsive MOFs, with their unique advantages, have captured greater interest from researchers. This review will delve into the merits and drawbacks of both endogenous and exogenous stimuli-responsive MOFs, along with their application directions. Furthermore, it will outline the characteristics of different synthesis routes of MOFs, exploring various design schemes and modification strategies and their impacts on the properties of MOF products, as well as how to control them. Additionally, we will survey different types of stimuli-responsive MOFs, discussing the significance of various MOF products reported in biomedical applications. We will categorically summarize different strategies such as anticancer therapy, antibacterial treatment, tissue repair, and biomedical imaging, as well as insights into the development of novel MOFs nanomaterials in the future. Finally, this review will conclude by summarizing the challenges in the development of stimuli-responsive MOFs in the field of biomedicine and providing prospects for future research endeavors.

Reprogramming Tumor-Associated Macrophages with a Se-Based Core-Satellite Nanoassembly to Enhance Cancer Immunotherapy

Tumor-associated macrophages (TAMs), as the most prevalent immune cells in the tumor microenvironment, play a pivotal role in promoting tumor development through various signaling pathways. Herein, we have engineered a Se@ZIF-8 core-satellite nanoassembly to reprogram TAMs, thereby enhancing immunotherapy outcomes. When the nanoassembly reaches the tumor tissue, selenium nanoparticles and Zn2+ are released in response to the acidic tumor microenvironment, resulting in a collaborative effort to promote the production of reactive oxygen species (ROS). The generated ROS, in turn, activate the nuclear factor κB (NF-κB) signaling pathway, driving the repolarization of TAMs from M2-type to M1-type, effectively eliminating cancer cells. Moreover, the nanoassembly can induce the immunogenic death of cancer cells through excess ROS to expose calreticulin and boost macrophage phagocytosis. The Se@ZIF-8 core-satellite nanoassembly provides a potential paradigm for cancer immunotherapy by reversing the immunosuppressive microenvironment.

Iron-Confined CRISPR/Cas9-Ribonucleoprotein Delivery System for Redox-Responsive Gene Editing

Clustered regularly interspaced short palindromic repeat (CRISPR)-associated protein 9 (Cas9) is a promising gene editing tool to treat diseases at the genetic level. Nonetheless, the challenge of the safe and efficient delivery of CRISPR/Cas9 to host cells constrains its clinical applicability. In the current study, a facile, redox-responsive CRISPR/Cas9-Ribonucleoprotein (RNP) delivery system by combining iron-coordinated aggregation with liposomes (Fe-RNP@L) is reported. The Fe-RNP is formed by the coordination of Fe3+ with amino and carboxyl groups of Cas9, which modifies the lipophilicity and surface charge of RNP and alters cellular uptake from primary endocytosis to endocytosis and cholesterol-dependent membrane fusion. RNP can be rapidly and reversibly released from Fe-RNP in response to glutathione without loss of structural integrity and enzymatic activity. In addition, iron coordination also improves the stability of RNP and substantially mitigates cytotoxicity. This construct enabled highly efficient cytoplasmic/nuclear delivery (≈90%) and gene-editing efficiency (≈70%) even at low concentrations. The high payload content, high editing efficiency, good stability, low immunogenicity, and ease of production and storage, highlight its potential for diverse genome editing and clinical applications.

Mitochondrial-Targeted Copper Delivery for Cuproptosis-Based Synergistic Cancer Therapy

Cuproptosis is dependent on mitochondrial respiration modulation by targeting lipoylated tricarboxylic acid cycle (TCA) cycle proteins, showing great potential in cancer treatment. However, the specific release of copper ions at mitochondrial is highly needed and still a major challenge to trigger cellular cuproptosis. Herein, a metal-organic framework-based nanoplatform (ZCProP) is designed for mitochondrial-targeted and ATP/pH-responsive Cu2+ and prodigiosin release. The released Cu2+ promotes aggregation of lipoylated protein and loss of Fe-S cluster protein, resulting in cell cuproptosis. In the meanwhile, Cu2+ can concert with prodigiosin to induce mitochondrial dysfunction and DNA damage and enhance cell cuproptosis. Furthermore, this nanoplatform has an ability to deplete glutathione, which not only further promotes cuproptosis but also triggers cell ferroptosis by the suppression of glutathione peroxidase 4, an anti-ferroptosis protein. Collectively, the designed ZCProP nanoplatform can responsively release cargos at mitochondrial and realize a conspicuous therapeutic efficacy through a cuproptosis-mediated concerted effect. Along with its excellent biocompatibility, this nanoplatform may provide a novel therapeutic modality paradigm to boost cancer therapeutic strategies based on cuproptosis.

A Tumor Environment-Activated Photosensitized Biomimetic Nanoplatform for Precise Photodynamic Immunotherapy of Colon Cancer

Aggressive nature of colon cancer and current imprecise therapeutic scenarios simulate the development of precise and effective treatment strategies. To achieve this, a tumor environment-activated photosensitized biomimetic nanoplatform (PEG2000-SiNcTI-Ph/CpG-ZIF-8@CM) is fabricated by encapsulating metal-organic framework loaded with developed photosensitizer PEG2000-SiNcTI-Ph and immunoadjuvant CpG oligodeoxynucleotide within fusion cell membrane expressing programmed death protein 1 (PD-1) and cluster of differentiation 47 (CD47). By stumbling across, systematic evaluation, and deciphering with quantum chemical calculations, a unique attribute of tumor environment (low pH plus high concentrations of adenosine 5'-triphosphate (ATP))-activated photodynamic effect sensitized by long-wavelength photons is validated for PEG2000-SiNcTI-Ph/CpG-ZIF-8@CM, advancing the precision of cancer therapy. Moreover, PEG2000-SiNcTI-Ph/CpG-ZIF-8@CM evades immune surveillance to target CT26 colon tumors in mice mediated by CD47/signal regulatory proteins α (SIRPα) interaction and PD-1/programmed death ligand 1 (PD-L1) interaction, respectively. Tumor environment-activated photodynamic therapy realized by PEG2000-SiNcTI-Ph/CpG-ZIF-8@CM induces immunogenic cell death (ICD) to elicit anti-tumor immune response, which is empowered by enhanced dendritic cells (DC) uptake of CpG and PD-L1 blockade contributed by the nanoplatform. The photodynamic immunotherapy efficiently combats primary and distant CT26 tumors, and additionally generates immune memory to inhibit tumor recurrence and metastasis. The nanoplatform developed here provides insights for the development of precise cancer therapeutic strategies.

Dual pH- and ATP-Responsive Antibacterial Nanospray: On-Demand Release of Antibacterial Factors, Imaging Monitoring, and Accelerated Healing of Bacteria-Infected Wounds under NIR Activation

The prevalence of pathogenic bacterial infections with high morbidity and mortality poses a widespread challenge to the healthcare system. Therefore, it is imperative to develop nanoformulations capable of adaptively releasing antimicrobial factors and demonstrating multimodal synergistic antimicrobial activity. Herein, an NIR-activated multifunctional synergistic antimicrobial nanospray MXene/ZIF-90@ICG was prepared by incorporating ZIF-90@ICG nanoparticles onto MXene-NH2 nanosheets. MXene/ZIF-90@ICG can on-demand release the antimicrobial factors MXenes, ICG, and Zn2+ in response to variations in pH and ATP levels within the bacterial infection microenvironment. Under NIR radiation, the combination of MXenes, Zn2+, and ICG generated a significant amount of ROS and elevated heat, thereby enhancing the antimicrobial efficacy of PDT and PTT. Meanwhile, NIR excitation could accelerate the further release of ICG and Zn2+, realizing the multimodal synergistic antibacterial effect of PDT/PTT/Zn2+. Notably, introducing MXenes improved the dispersion of the synthesized antimicrobial nanoparticles in aqueous solution, rendering MXene/ZIF-90@ICG a candidate for application as a nanospray. Importantly, MXene/ZIF-90@ICG demonstrated antimicrobial activity and accelerated wound healing in the constructed in vivo subcutaneous Staphylococcus aureus infection model with NIR activation, maintaining a favorable biosafety level. Therefore, MXene/ZIF-90@ICG holds promise as an innovative nanospray for adaptive multimodal synergistic and efficient antibacterial applications with NIR activation.

Metal-Drug Coordination Nanoparticles and Hydrogels for Enhanced Delivery

Drug delivery is a key component of nanomedicine, and conventional delivery relies on the adsorption or encapsulation of drug molecules to a nanomaterial. Many delivery vehicles contain metal ions, such as metal-organic frameworks, metal oxides, transition metal dichalcogenides, MXene, and noble metal nanoparticles. These materials have a high metal content and pose potential long-term toxicity concerns leading to difficulties for clinical approval. In this review, recent developments are summarized in the use of drug molecules as ligands for metal coordination forming various nanomaterials and soft materials. In these cases, the drug-to-metal ratio is much higher than conventional adsorption-based strategies. The drug molecules are divided into small-molecule drugs, nucleic acids, and proteins. The formed hybrid materials mainly include nanoparticles and hydrogels, upon which targeting ligands can be grafted to improve efficacy and further decrease toxicity. The application of these materials for addressing cancer, viral infection, bacterial infection inflammatory bowel disease, and bone diseases is reviewed. In the end, some future directions are discussed from fundamental research, materials science, and medicine.

Targeted protein delivery based on stimuli-triggered nanomedicine

Protein-based drugs have shown unique advantages to treat various diseases in recent years. However, most protein therapeutics in clinical use are limited to extracellular targets with low delivery efficiency. To realize targeted protein delivery, a series of stimuli-triggered nanoparticle formulations have been developed to improve delivery efficiency and reduce off-target release. These smart nanoparticles are designed to release cargo proteins in response to either internal or external stimuli at pathological tissues. In this way, varieties of protein-based drugs including antibodies, enzymes, and pro-apoptotic proteins can be effectively delivered to desired sites for the treatment of cancer, inflammation, metabolic diseases, and so on with minimal side effects. In this review, recent advances in the design of stimuli-triggered nanomedicine for targeted protein delivery in different biomedical applications will be discussed. A deeper understanding of these emerging strategies helps develop more efficient protein delivery systems for clinical use in the future.

Autonomous Feedback-Driven Engineered DNAzyme-Coated Trojan Horse-like Nanocapsules for On-Demand CRISPR/Cas9 Delivery

Manipulating the expression of cellular genes through efficient CRISPR/Cas9 delivery is rapidly evolving into a desirable tumor therapeutics. The exposure of CRISPR/Cas9 to a complex external environment poses challenges for conventional delivery carriers in achieving responsive and accurate release. Here, we report a Trojan horse-like nanocapsule for the on-demand delivery of CRISPR/Cas9 in a microRNA-responsive manner, enabling precise tumor therapy. The nanocapsule comprises a nanoassembled, engineered DNAzyme shell encasing a Cas9/sgRNA complex core. The DNAzyme, functioning as a catalytic unit, undergoes a conformational change in the presence of tumor-associated microRNA, followed by activating a positive feedback-driven autonomous catabolic cycle of the nanocapsule shell. This catabolic cycle is accomplished through chain reactions of DNAzyme "cleavage-hybridization-cleavage", which ensures sensitivity in microRNA recognition and effective release of Cas9/sgRNA. Utilizing this Trojan horse-like nanocapsule, as low as 1.7 pM microRNA-21 can trigger the on-demand release of Cas9/sgRNA, enabling the specific editing of the protumorigenic microRNA coding gene. The resulting upregulation of tumor suppressor genes induces apoptosis in tumor cells, leading to significant inhibition of tumor growth by up to 75.94%. The Trojan horse-like nanocapsule, with superior programmability and biocompatibility, is anticipated to serve as a promising carrier for tailoring responsive gene editing systems, achieving enhanced antitumor specificity and efficacy.

Protein-Integrated Hydrogen-Bonded Organic Frameworks: Chemistry and Biomedical Applications

Hydrogen-bonded organic frameworks (HOFs) are porous nanomaterials that offer exceptional biocompatibility and versatility for integrating proteins for biomedical applications. This minireview concisely discusses recent advancements in the chemistry and functionality of protein-HOF interfaces. It particularly focuses on strategic methodologies, such as the careful selection of building blocks and the genetic engineering of proteins, to facilitate protein-HOF interactions. We examine the role of enzyme encapsulation within HOFs, highlighting its capability to preserve enzyme function, a crucial aspect for applications in biosensing and disease diagnosis. Moreover, we discuss the emerging utility of nanoscale HOFs for intracellular protein delivery, illustrating their applicability as nanoreactors for intracellular catalysis and neuroprotective biorthogonal catalysis within cellular compartments. We highlight the significant advancement of designing biodegradable HOFs tailored for cytosolic protein delivery, underscoring their promising application in targeted cancer therapies. Finally, we provide a perspective viewpoint on the design of biocompatible protein-HOF assemblies, underlining their promising prospects in drug delivery, disease diagnosis, and broader biomedical applications.

Polyphenol-Assisted Biomineralization of Metal-Organic Framework Nanoparticles for Precision Delivery of Therapeutic Proteins to Cancer Cells

The delivery of proteins into the cytosol holds great promise for cell signaling manipulation and the development of precision medicine. However, this potency is challenged by achieving targeted and controlled delivery, specifically within diseased cells. In this study, we introduce a versatile and effective method for the precision delivery of therapeutic proteins to cancer cells by designing polyphenol-assisted biomineralization of zeolite imidazole framework-8 (ZIF-8). We demonstrate that by leveraging the strong noncovalent binding affinity of epigallocatechin gallate (EGCG) with both proteins and ZIF-8, our approach significantly enhances the biomineralization of ZIF-8, which in turn improves the efficiency of protein encapsulation and intracellular delivery. Moreover, the incorporation of EGCG within ZIF-8 enables controlled degradation of the nanoparticles and the selective release of the encapsulated proteins in cancer cells. This selective release is triggered by the oxidation of EGCG in response to the high levels of reactive oxygen species (ROS) found within cancer cells that destabilize the EGCG/ZIF-8 nanoparticles. We have further demonstrated the ability of EGCG/ZIF-8 to deliver a wide range of proteins into cancer cells, including bacterial virulence protein, to rewire cell signaling and prohibit tumor cell growth in a mouse xenograft model. Our strategy and findings underscore the potential of designing the EGCG/ZIF-8 interface for specific and controlled protein delivery for targeted cancer therapy.

Second near-infrared fluorescent Metal-Organic framework sensors for in vivo extracellular adenosine triphosphate monitoring

Plant nanobionic sensors enable real-time monitoring of signaling molecules in plants by interfacing them with specifically designed nanoprobes, which have been acknowledged as species-independent analytical tools. In this study, we developed a plant nanobionic sensor for in vivo detection of extracellular adenosine triphosphate (eATP) in living plants by designing a novel second near-infrared (NIR-II) fluorescent metal-organic framework (MOF) nanoprobe. The NIR-II fluorescent nanoprobe (IR-1061 micelle@ZIF-90) with a sandwich structure was synthesized by successive encapsulation of the hydrophobic NIR-II dye IR-1061 with the amphipathic polymer DSPE-mPEG 2000 and MOF ZIF-90. Interestingly, coating ZIF-90 around IR-1061 micelles increased the NIR-II fluorescence 16.6-fold. Utilizing the ultrahigh NIR-II fluorescent emission of the designed nanoprobes and specific recognition of ZIF-90 to ATP, the nanoprobes were applied to spatial and temporal monitoring eATP in model and non-model plants under environmental stress.

Biomaterial-Based CRISPR/Cas9 Delivery Systems for Tumor Treatment

CRISPR/Cas9 gene editing technology is characterized by high specificity and efficiency, and has been applied to the treatment of human diseases, especially tumors involving multiple genetic modifications. However, the clinical application of CRISPR/Cas9 still faces some major challenges, the most urgent of which is the development of optimized delivery vectors. Biomaterials are currently the best choice for use in CRISPR/Cas9 delivery vectors owing to their tunability, biocompatibility, and efficiency. As research on biomaterial vectors continues to progress, hope for the application of the CRISPR/Cas9 system for clinical oncology therapy builds. In this review, we first detail the CRISPR/Cas9 system and its potential applications in tumor therapy. Then, we introduce the different delivery forms and compare the physical, viral, and non-viral vectors. In addition, we analyze the characteristics of different types of biomaterial vectors. We further review recent research progress in the use of biomaterials as vectors for CRISPR/Cas9 delivery to treat specific tumors. Finally, we summarize the shortcomings and prospects of biomaterial-based CRISPR/Cas9 delivery systems.

Non-viral systems for intracellular delivery of genome editing tools

A hallmark of the last decades is an extensive development of genome editing systems and technologies propelling genetic engineering to the next level. Specific and efficient delivery of genome editing tools to target cells is one of the key elements of such technologies. Conventional vectors are not always suitable for this purpose due to a limited cargo volume, risks related to cancer and immune reactions, toxicity, a need for high-purity viral material and quality control, as well as a possibility of integration of the virus into the host genome leading to overexpression of the vector components and safety problems. Therefore, the search for novel approaches to delivering proteins and nucleic acids into cells is a relevant priority. This work reviews abiotic vectors and systems for delivering genome editing tools into target cells, including liposomes and solid lipid particles, other membrane-based vesicles, cell-penetrating peptides, micelles, dendrimers, carbon nanotubes, inorganic, polymer, metal and other nanoparticles. It considers advantages, drawbacks and preferred applications of such systems as well as suitability thereof for the delivery of genome editing systems. A particular emphasis is placed on metal-organic frameworks (MOFs) and their potential in the targeted intracellular delivery of proteins and polynucleotides. It has been concluded that further development of MOF-based vectors and technologies, as well as combining MOFs with other carriers can result in safe and efficient delivery systems, which would be able to circulate in the body for a long time while recognizing target cells and ensuring cell-specific delivery and release of intact cargoes and, thereby, improving the genome editing outcome.

Biomedical application of metal-organic frameworks (MOFs) in cancer therapy: Stimuli-responsive and biomimetic nanocomposites in targeted delivery, phototherapy and diagnosis

The nanotechnology is an interdisciplinary field that has become a hot topic in cancer therapy. Metal-organic frameworks (MOFs) are porous materials and hybrid composites consisted of organic linkers and metal cations. Despite the wide application of MOFs in other fields, the potential of MOFs for purpose of cancer therapy has been revealed by the recent studies. High surface area and porosity, significant drug loading and encapsulation efficiency are among the benefits of using MOFs in drug delivery. MOFs can deliver genes/drugs with selective targeting of tumor cells that can be achieved through functionalization with ligands. The photosensitizers and photo-responsive nanostructures including carbon dots and gold nanoparticles can be loaded in/on MOFs to cause phototherapy-mediated tumor ablation. The immunogenic cell death induction and increased infiltration of cytotoxic CD8+ and CD4+ T cells can be accelerated by MOF platforms in providing immunotherapy of tumor cells. The stimuli-responsive MOF platforms responsive to pH, redox, enzyme and ion can accelerate release of therapeutics in tumor site. Moreover, MOF nanocomposites can be modified ligands and green polymers to improve their selectivity and biocompatibility for cancer therapy. The application of MOFs for the detection of cancer-related biomarkers can participate in the early diagnosis of patients.

Hydrogel-encapsulated medium chain lipid-modified zeolite imidazole framework-90 as a promising platform for oral delivery of proteins

The administration of protein therapeutics through oral means is seen as a convenient and painless experience for patients, making it a significant consideration in the field of drug delivery. Nevertheless, the challenging conditions within the gastrointestinal tract, along with the obstacles to absorption, impede the efficient transportation of proteins. Here, we successfully implemented post-synthetic modifications to attach medium-chain lipids (C10) onto the surface of zeolitic imidazole framework-90 (ZIF-90), then encapsulated the nanoparticles with sodium alginate, resulting in a potential platform for the oral administration of proteins. By means of biomimetic mineralization, ZIF-90 achieves a simple and efficient encapsulation of proteins of varying sizes, while shielding them against degradation by digestive enzymes. Sodium alginate hydrogel protects proteins against gastric acid and helps the cargo to rapidly penetrate the mucus layer. Through a mixed mechanism dominated by micropinocytosis, the C10-conjugated ZIF-90 (ZIF-90-C10) can be uptake by Caco-2 cells with a 200-400% increase and transported through the Golgi apparatus after escaping from lysosomes, exhibiting enhanced uptake in the overall gastrointestinal tract. Furthermore, ZIF-90-C10 retains its adenosine triphosphate-responsive release, which drastically lowers the likelihood of accumulation in vivo and allows targeted delivery for disease cells. Our work highlights mid-chain lipid conjugation as a potent approach to enhancing nanoparticle delivery efficiency and a potential strategy for oral delivery of biomacromolecules when combined with pH-responsive gels.

Recent advances in metal-organic frameworks for stimuli-responsive drug delivery

After entering the human body, drugs for treating diseases, which are prone to delivery and release in an uncontrolled manner, are affected by various factors. Based on this, many researchers utilize various microenvironmental changes encountered during drug delivery to trigger drug release and have proposed stimuli-responsive drug delivery systems. In recent years, metal-organic frameworks (MOFs) have become promising stimuli-responsive agents to release the loaded therapeutic agents at the target site to achieve more precise drug delivery due to their high drug loading, excellent biocompatibility, and high stimuli-responsiveness. The MOF-based stimuli-responsive systems can respond to various stimuli under pathological conditions at the site of the lesion, releasing the loaded therapeutic agent in a controlled manner, and improving the accuracy and safety of drug delivery. Due to the changes in different physical and chemical factors in the pathological process of diseases, the construction of stimuli-responsive systems based on MOFs has become a new direction in drug delivery and controlled release. Based on the background of the rapidly increasing attention to MOFs applied in drug delivery, we aim to review various MOF-based stimuli-responsive drug delivery systems and their response mechanisms to various stimuli. In addition, the current challenges and future perspectives of MOF-based stimuli-responsive drug delivery systems are also discussed in this review.

Advanced strategies for CRISPR/Cas9 delivery and applications in gene editing, therapy, and cancer detection using nanoparticles and nanocarriers

Cancer remains one of the deadliest diseases, and is characterised by the uncontrolled growth of modified human cells. Unlike infectious diseases, cancer does not originate from foreign agents. Though a variety of diagnostic procedures are available; their cost-effectiveness and accessibility create significant hurdles. Non-specific cancer symptoms further complicate early detection, leading to belated recognition of certain cancer. The lack of reliable biomarkers hampers effective treatment, as chemotherapy, radiation therapy, and surgery often result in poor outcomes and high recurrence rates. Genetic and epigenetic mutations play a crucial role in cancer pathogenesis, necessitating the development of alternate treatment methods. The advent of CRISPR/Cas9 technology has transformed molecular biology and exhibits potential for gene modification and therapy in various cancer types. Nonetheless, obstacles such as safe transport, off-target consequences, and potency must be overcome before widespread clinical use. Notably, this review delves into the multifaceted landscape of cancer research, highlighting the pivotal role of nanoparticles in advancing CRISPR/Cas9-based cancer interventions. By addressing the challenges associated with cancer diagnosis and treatment, this integrated approach paves the way for innovative solutions and improved patient outcomes.

Logic-gated tumor-microenvironment nanoamplifier enables targeted delivery of CRISPR/Cas9 for multimodal cancer therapy

Recent innovations in nanomaterials inspire abundant novel tumor-targeting CRISPR-based gene therapies. However, the therapeutic efficiency of traditional targeted nanotherapeutic strategies is limited by that the biomarkers vary in a spatiotemporal-dependent manner with tumor progression. Here, we propose a self-amplifying logic-gated gene editing strategy for gene/H2O2-mediated/starvation multimodal cancer therapy. In this approach, a hypoxia-degradable covalent-organic framework (COF) is synthesized to coat a-ZIF-8 in which glucose oxidase (GOx) and CRISPR system are packaged. To intensify intracellular redox dyshomeostasis, DNAzymes which can cleave catalase mRNA are loaded as well. When the nanosystem gets into the tumor, the weakly acidic and hypoxic microenvironment degrades the ZIF-8@COF to activate GOx, which amplifies intracellular H+ and hypoxia, accelerating the nanocarrier degradation to guarantee available CRISPR plasmid and GOx release in target cells. These tandem reactions deplete glucose and oxygen, leading to logic-gated-triggered gene editing as well as synergistic gene/H2O2-mediated/starvation therapy. Overall, this approach highlights the biocomputing-based CRISPR delivery and underscores the great potential of precise cancer therapy.

Delivery of external proteins into the cytoplasm using protein capsules modified with IgG on the surface, created from the amphiphilic two helix-bundle protein OLE-ZIP

This study explores a new method for delivering therapeutic proteins into specific cells using OLE-ZIP capsules that present IgG. OLE-ZIP capsules is a spherical caspules prepared from amphihilic dimetic coiled-coil peptide, OLE-ZIP. Upon presenting cetuximab, these capsules showed preferential uptake in A431 cells and increased cytotoxicity when loaded with RNase A.

SERS Immunoassay Based on an Enzyme-Catalyzed Cascade Reaction and Metal-Organic Framework/Alkaline Phosphatase for Ultrasensitive Detection of Adenosine Triphosphate

Herein, an adenosine triphosphate (ATP)-induced enzyme-catalyzed cascade reaction system based on metal-organic framework/alkaline phosphatase (MOF/ALP) nanocomposites was designed to establish a surface-enhanced Raman spectroscopy (SERS) biosensor for use in rapid, sensitive ATP detection. Numerous ALP molecules were first encapsulated using ZIF-90 to temporarily deactivate the enzyme activity, similar to a lock. Au nanostars (AuNSs), as SERS-enhancing substrates, were combined with o-phenylenediamine (OPD) to form AuNSs@OPD, which could significantly improve the Raman signal of OPD. When the target ATP interacted with the MOF/ALP nanocomposites, ATP could act as a key to open the MOF structure, releasing ALP, which should further catalyze the conversion of OPD to oxOPD with the aid of ascorbic acid 2-phosphate. Therefore, with the increasing concentrations of ATP, more ALP was released to catalyze the conversion of OPD, resulting in the reduced intensity of the Raman peak at 1262 cm-1, corresponding to the level of OPD. Based on this principle, the ATP-induced enzyme-catalyzed cascade reaction SERS biosensor enabled the ultrasensitive detection of ATP, with a low detection limit of 0.075 pM. Consequently, this study provides a novel strategy for use in the ultrasensitive, rapid detection of ATP, which displays considerable potential for application in the fields of biomedicine and disease diagnosis.

Confinement in Dual-Chain-Locked DNA Origami Nanocages Programs Marker-Responsive Delivery of CRISPR/Cas9 Ribonucleoproteins

Delivery of CRISPR/Cas9 ribonucleoproteins (RNPs) offers a powerful tool for therapeutic genome editing. However, precise manipulation of CRISPR/Cas9 RNPs to switch the machinery on and off according to diverse disease microenvironments remains challenging. Here, we present dual-chain-locked DNA origami nanocages (DL-DONCs) that can confine Cas9 RNPs in the inner cavity for efficient cargo delivery and dual-marker-responsive genome editing in the specified pathological states. By engineering of ATP or miRNA-21-responsive dsDNAs as chain locks on the DONCs, the permeability of nanocages and accessibility of encapsulated Cas9 RNPs can be finely regulated. The resulting DL-DONCs enabled steric protection of bioactive Cas9 RNPs from premature release and deactivation during transportation while dismounting the dual chain locks in response to molecular triggers after internalization into tumor cells, facilitating the escape of Cas9 RNPs from the confinement for gene editing. Due to the dual-marker-dominated uncaging mechanism, the gene editing efficiency could be exclusively determined by the combined level of ATP and miRNA-21 in the target cellular environment. By targeting the tumor-associated PLK-1 gene, the DL-DONCs-enveloped Cas9 RNPs have demonstrated superior inhibitory effects on the proliferation of tumor cells in vitro and in vivo. The developed DL-DONCs provide a custom-made platform for the precise manipulation of Cas9 RNPs, which can be potentially applied to on-demand gene editing for classified therapy in response to arbitrary disease-associated biomolecules.

Transforming Intratumor Bacteria into Immunopotentiators to Reverse Cold Tumors for Enhanced Immuno-chemodynamic Therapy of Triple-Negative Breast Cancer

Immunotherapy of triple-negative breast cancer (TNBC) has an unsatisfactory therapeutic outcome due to an immunologically "cold" microenvironment. Fusobacterium nucleatum (F. nucleatum) was found to be colonized in triple-negative breast tumors and was responsible for the immunosuppressive tumor microenvironment and tumor metastasis. Herein, we constructed a bacteria-derived outer membrane vesicle (OMV)-coated nanoplatform that precisely targeted tumor tissues for dual killing of F. nucleatum and cancer cells, thus transforming intratumor bacteria into immunopotentiators in immunotherapy of TNBC. The as-prepared nanoparticles efficiently induced immunogenic cell death through a Fenton-like reaction, resulting in enhanced immunogenicity. Meanwhile, intratumoral F. nucleatum was killed by metronidazole, resulting in the release of pathogen-associated molecular patterns (PAMPs). PAMPs cooperated with OMVs further facilitated the maturation of dendritic cells and subsequent T-cell infiltration. As a result, the "kill two birds with one stone" strategy warmed up the cold tumor environment, maximized the antitumor immune response, and achieved efficient therapy of TNBC as well as metastasis prevention. Overall, this strategy based on a microecology distinction in tumor and normal tissue as well as microbiome-induced reversal of cold tumors provides new insight into the precise and efficient immune therapy of TNBC.

Clustered Regularly Interspaced Short Palindromic Repeats and Clustered Regularly Interspaced Short Palindromic Repeats-Associated Protein 9 System: Factors Affecting Precision Gene Editing Efficiency and Optimization Strategies

The clustered regularly interspaced short palindromic repeat (CRISPR)-CRISPR-associated (Cas) system is a powerful genomic DNA editing tool. The increased applications of gene editing tools, including the CRISPR-Cas system, have contributed to recent advances in biological fields, such as genetic disease therapy, disease-associated gene screening and detection, and cancer therapy. However, the major limiting factor for the wide application of gene editing tools is gene editing efficiency. This review summarizes the recent advances in factors affecting the gene editing efficiency of the CRISPR-Cas9 system and the CRISPR-Cas9 system optimization strategies. The homology-directed repair efficiency-related signal pathways and the form and delivery method of the CRISPR-Cas9 system are the major factors that influence the repair efficiency of gene editing tools. Based on these influencing factors, several strategies have been developed to improve the repair efficiency of gene editing tools. This review provides novel insights for improving the repair efficiency of the CRISPR-Cas9 gene editing system, which may enable the development and improvement of gene editing tools.

Biodegradable Hydrogen-Bonded Organic Framework for Cytosolic Protein Delivery

Hydrogen-bonded organic frameworks (HOFs) are a novel class of porous nanomaterials that show great potential for intracellular delivery of protein therapeutics. However, the inherent challenges in interfacing protein with HOFs, and the need for spatiotemporally controlling the release of protein within cells, have constrained their therapeutic potential. In this study, we report novel biodegradable hydrogen-bonded organic frameworks, termed DS-HOFs, specially designed for the cytosolic delivery of protein therapeutics in cancer cells. The synthesis of DS-HOFs involves the self-assembly of 4-[tris(4-carbamimidoylphenyl) methyl] benzenecarboximidamide (TAM) and 4,4'-dithiobisbenzoic acid (DTBA), governed by intermolecular hydrogen-bonding interactions. DS-HOFs exhibit high efficiency in encapsulating a diverse range of protein cargos, underpinned by the hydrogen-bonding interactions between the protein residue and DS-HOF subcomponents. Notably, DS-HOFs are selectively degraded in cancer cells triggered by the distinct intracellular reductive microenvironments, enabling an enhanced and selective release of protein inside cancer cells. Additionally, we demonstrate that the efficient delivery of bacterial effector protein DUF5 using DS-HOFs depletes the mutant RAS in cancer cells to prohibit tumor cell growth both in vitro and in vivo. The design of biodegradable HOFs for cytosolic protein delivery provides a powerful and promising strategy to expand the therapeutic potential of proteins for cancer therapy.

Neuroprotective Bioorthogonal Catalysis in Mitochondria Using Protein-Integrated Hydrogen-Bonded Organic Frameworks

Mitochondria-targeted bioorthogonal catalysis holds promise for controlling cell function precisely, yet achieving selective and efficient chemical reactions within organelles is challenging. In this study, we introduce a new strategy using protein-integrated hydrogen-bonded organic frameworks (HOFs) to enable synergistic bioorthogonal chemical catalysis and enzymatic catalysis within mitochondria. Utilizing catalytically active tris(4,4'-dicarboxylicacid-2,2'-bipyridyl) ruthenium(II) to self-assemble with [1,1'-biphenyl]-4,4'-biscarboximidamide, we synthesized nanoscale RuB-HOFs that exhibit high photocatalytic reduction activity. Notably, RuB-HOFs efficiently enter cells and preferentially localize to mitochondria, where they facilitate bioorthogonal photoreduction reactions. Moreover, we show that RuB-HOFs encapsulating catalase can produce hydrogen sulfide (H2 S) in mitochondria through photocatalytic reduction of pro-H2 S and degrade hydrogen peroxide through enzymatic catalysis simultaneously, offering a significant neuroprotective effect against oxidative stress. Our findings not only introduce a versatile chemical toolset for mitochondria-targeted bioorthogonal catalysis for prodrug activation but also pave the way for potential therapeutic applications in treating diseases related to cellular oxidative stress.

DNA-Functionalized Porphyrinic Metal-Organic Framework-Based Drug Delivery System for Targeted Bimodal Cancer Therapy

A DNA-functionalized porphyrinic MOF (porMOF) drug delivery system was successfully constructed. porMOF as a photosensitizer and drug delivery carrier can integrate photodynamic therapy (PDT) and chemotherapy. Via the strong coordination interaction between the zirconium cluster of porMOF and the terminal phosphate group of DNA, the stable modification of the DNA layer on the porMOF surface is achieved. Meanwhile, the introduction of C/G-rich base pairs into the DNA double-stranded structure provides more binding sites of chemotherapeutic drug doxorubicin (DOX). AS1411, an aptamer of nucleolin proteins that are overexpressed by cancer cells, is introduced in the double-stranded terminal, which can endow the nanosystem with the ability to selectively recognize cancer cells. C-rich sequences in DNA double strands form an i-motif structure under acidic conditions to promote the highly efficient release of DOX in cancer cells. In vitro and in vivo experiments demonstrate that the synergistic PDT/chemotherapy modality achieves highly efficient cancer cell killing and tumor ablation without undesirable side effects.

Rational design of copper(I)-doped metal-organic frameworks as dual-functional nanocarriers for combined chemo-chemodynamic therapy

Combination therapies are an increasingly important part of the antitumor medicine armamentarium. However, developing desirable nanomaterials for combination therapies is still a great challenge. Herein, a biocompatible Cu(I)-doped metal-organic framework (MOF) (denoted as CuZn-ZIF) is designed as a novel dual-functional nanocarrier. Doxorubicin molecules are covalently bound to the surface of the CuZn-ZIF and released by the cleavage of chemical bonds in an acidic environment, demonstrating the capacity of controlled drug release. More importantly, CuZn-ZIF nanocarriers can simultaneously play the role of nanocatalysts, capable of catalyzing H2O2 into a highly reactive intracellular toxic hydroxyl radical (˙OH). An in vivo study reveals that nanoparticles exhibit high antitumor efficacy through the combined performance of DOX and Cu(I), proving the great potential of this copper(I)-based MOF for combined chemo-chemotherapy to improve therapeutic efficacy.

Histidine-Rich Protein Accelerates the Biomineralization of Zeolitic Imidazolate Frameworks for In Vivo Protein Delivery

Biomineralization of metal-organic frameworks (MOFs) provides a powerful approach for intracellular protein delivery, enabling the study of biological function and therapeutic potential of proteins. However, the potency of this approach is largely challenged by the low efficiency of current strategies for interfacing proteins with MOFs for biomineralization and intracellular delivery. Here, we report a versatile and convenient biomineralization strategy for the rapid encapsulation and enhanced delivery of proteins using MOFs, accelerated by histidine-rich proteins. We demonstrate that the histidine-rich green fluorescent protein (H39GFP) can accelerate the biomineralization of MOFs by promoting the coordination between proteins and metal ions, leading to enhanced protein delivery efficiency up to 15-fold. Moreover, we show that the delivery of H39GFP-fused cytotoxic ribonuclease and bacterial-derived RAS protease can effectively inhibit tumor cell growth. The strategy of promoting the biomineralization of MOFs via histidine-rich proteins for enhanced intracellular delivery could be expanded to other biomacromolecules, advancing their therapeutic potential and the biomedical scope of MOFs.

Metal-Organic Frameworks Meet Polymers: From Synthesis Strategies to Healthcare Applications

Metal-organic frameworks (MOFs) have been at the forefront of nanotechnological research for the past decade owing to their high porosity, high surface area, diverse configurations, and controllable chemical structures. They are a rapidly developing class of nanomaterials that are predominantly applied in batteries, supercapacitors, electrocatalysis, photocatalysis, sensors, drug delivery, gas separation, adsorption, and storage. However, the limited functions and unsatisfactory performance of MOFs resulting from their low chemical and mechanical stability hamper further development. Hybridizing MOFs with polymers is an excellent solution to these problems, because polymers-which are soft, flexible, malleable, and processable-can induce unique properties in the hybrids based on those of the two disparate components while retaining their individuality. This review highlights recent advances in the preparation of MOF-polymer nanomaterials. Furthermore, several applications wherein the incorporation of polymers enhances the MOF performance are discussed, such as anticancer therapy, bacterial elimination, imaging, therapeutics, protection from oxidative stress and inflammation, and environmental remediation. Finally, insights from the focus of existing research and design principles for mitigating future challenges are presented.

Recent advances in glucose-oxidase-based nanocomposites for diabetes diagnosis and treatment

Glucose oxidase (GOx) has attracted a lot of attention in the field of diabetes diagnosis and treatment in recent years owing to its inherent biocompatibility and glucose-specific catalysis. GOx can effectively catalyze the oxidation of glucose in the blood to hydrogen peroxide (H2O2) and glucuronic acid and can be used as a sensitive element in biosensors to detect blood glucose concentrations. Nanomaterials based on the immobilization of GOx can significantly improve the performance of glucose sensors through, for example, reduced electron tunneling distance. Moreover, various insulin-loaded nanomaterials (e.g., metal-organic backbones, and mesoporous silica nanoparticles) have been developed for the control of blood glucose concentrations based on GOx catalytic chemistry. These nano-delivery carriers are capable of releasing insulin in response to GOx-mediated changes in the microenvironment, allowing for a rapid return of the blood microenvironment to a normal state. Therefore, glucose biosensors and insulin delivery vehicles immobilized with GOx are important tools for the diagnosis and treatment of diabetes. This paper reviews the characteristics of various GOx-based nanomaterials developed for glucose biosensing and insulin-responsive release as well as research progress, and also highlights the current challenges and opportunities facing this field.

Cascade dynamic assembly/disassembly of DNA nanoframework enabling the controlled delivery of CRISPR-Cas9 system

CRISPR-Cas9 has been explored as a therapeutic agent for down-regulating target genes; the controlled delivery of Cas9 ribonucleoprotein (RNP) is essential for therapeutic efficacy and remains a challenge. Here, we report cascade dynamic assembly/disassembly of DNA nanoframework (NF) that enables the controlled delivery of Cas9 RNP. NF was prepared with acrylamide-modified DNA that initiated cascade hybridization chain reaction (HCR). Through an HCR, single-guide RNA was incorporated to NF; simultaneously, the internal space of NF was expanded, facilitating the loading of Cas9 protein. NF was designed with hydrophilic acylamino and hydrophobic isopropyl, allowing dynamic swelling and aggregation. The responsive release of Cas9 RNP was realized by introducing disulfide bond-containing N,N-bis(acryloyl)cystamine that was specifically in response to glutathione of cancer cells, triggering the complete disassembly of NF. In vitro and in vivo investigations demonstrated the high gene editing efficiency in cancer cells, the hypotoxicity in normal cells, and notable antitumor efficacy in a breast cancer mouse model.

Designs of metal-organic framework nanoparticles for protein delivery

Recently, there has been high interest in developing metal-organic framework (MOF) nanoparticles (NPs) for delivering therapeutic proteins, propelled mainly by the unique hierarchical porous structures of MOFs for protein encapsulation. Novel design strategies have emerged for broad therapeutic applications and clinical translations, leading to multifunctional MOF-NPs with improved biointerfacing capabilities and higher potency. This review summarizes recent MOF-NP designs specifically for protein delivery. The summary focuses on four design categories, including environment-responsive MOF-NPs for on-demand protein delivery, cell membrane-coated MOF-NPs for biomimetic protein delivery, cascade reaction-incorporated MOF-NPs for combinatorial protein delivery, and composite MOF-NPs for intelligent protein delivery. The major challenges and opportunities in using MOF-NPs for protein delivery are also discussed. Overall, this review will promote designs of MOF-NPs with unique properties to address unmet medical needs.

CRISPR/Cas9-based application for cancer therapy: Challenges and solutions for non-viral delivery

CRISPR/Cas9 genome editing is a promising therapeutic technique, which makes precise and rapid gene editing technology possible on account of its high sensitivity and efficiency. CRISPR/Cas9 system has been proved to able to effectively disrupt and modify genes, which shows great potential for cancer treatment. Current researches proves that virus vectors are capable of effectively delivering the CRISPR/Cas9 system, but immunogenicity and carcinogenicity caused by virus transmission still trigger serious consequences. Therefore, the greatest challenge of CRISPR/Cas9 for cancer therapy lies on how to deliver it to the target tumor site safely and effectively. Non-viral delivery systems with specific targeting, high loading capacity, and low immune toxicity are more suitable than viral vectors, which limited by uncontrollable side effects. Their medical advances and applications have been widely concerned. Herein, we present the molecule mechanism and different construction strategies of CRISPR/Cas9 system for editing genes at the beginning of this research. Subsequently, several common CRISPR/Cas9 non-viral deliveries for cancer treatment are introduced. Lastly, based on the main factors limiting the delivery efficiency of non-viral vectors proposed in the existing researches and literature, we summarize and discuss the main methods to solve these limitations in the existing tumor treatment system, aiming to introduce further optimization and innovation of the CRISPR/Cas9 non-viral delivery system suitable for cancer treatment.

Multifunctional Gold-Silver-Carbon Quantum Dots Nano-Hybrid Composite: Advancing Antibacterial Wound Healing and Cell Proliferation

The urgent need for innovative materials that effectively eliminate bacteria while promoting cell growth to accelerate wound healing has led to the exploration of new options, as current antimicrobial nanoparticles often exhibit high cytotoxicity, which hinders wound closure. In this study, a nano-hybrid composite, named gold-silver-carbon quantum dots (AuAg-CDs), was prepared by embedding gold and silver nanoclusters into carbon dots. The AuAg-CDs nano-hybrid composite demonstrates remarkable biocompatibility, displays potent antibacterial activity, and possesses a unique capability to promote cell proliferation. By physically disrupting bacterial membranes and promoting mammalian cell proliferation, this composite emerges as a highly promising material for wound healing applications. The underlying mechanism of the multifunctional AuAg-CDs was investigated through comprehensive analyses encompassing cell morphology, bacterial membrane potential, levels of reactive oxygen species (ROS), and adenosine triphosphate (ATP) production in both bacterial and mammalian cells. Additionally, AuAg-CDs were incorporated into alginate to create a hydrogel wound dressing, which underwent evaluation using animal models. The results underscore the remarkable potential of the AuAg-CDs wound dressing in facilitating the proliferation of wound fibroblasts and combating bacterial infections. The significance of designing multifunctional nanomaterials to address the challenges associated with pathogenic bacterial infections and regenerative medicine is highlighted by this study, paving the way for future advancements in these fields.

Design and fabrication of intracellular therapeutic cargo delivery systems based on nanomaterials: current status and future perspectives

Intracellular cargo delivery, the introduction of small molecules, proteins, and nucleic acids into a specific targeted site in a biological system, is an important strategy for deciphering cell function, directing cell fate, and reprogramming cell behavior. With the advancement of nanotechnology, many researchers use nanoparticles (NPs) to break through biological barriers to achieving efficient targeted delivery in biological systems, bringing a new way to realize efficient targeted drug delivery in biological systems. With a similar size to many biomolecules, NPs possess excellent physical and chemical properties and a certain targeting ability after functional modification on the surface of NPs. Currently, intracellular cargo delivery based on NPs has emerged as an important strategy for genome editing regimens and cell therapy. Although researchers can successfully deliver NPs into biological systems, many of them are delivered very inefficiently and are not specifically targeted. Hence, the development of efficient, target-capable, and safe nanoscale drug delivery systems to deliver therapeutic substances to cells or organs is a major challenge today. In this review, on the basis of describing the research overview and classification of NPs, we focused on the current research status of intracellular cargo delivery based on NPs in biological systems, and discuss the current problems and challenges in the delivery process of NPs in biological systems.

Lipid-, Inorganic-, Polymer-, and DNA-Based Nanocarriers for Delivery of the CRISPR/Cas9 system

The clustered regularly interspaced short palindromic repeat (CRISPR)/associated protein 9 (CRISPR/Cas9) system has been widely explored for the precise manipulation of target DNA and has enabled efficient genomic editing in cells. Recently, CRISPR/Cas9 has shown promising potential in biomedical applications, including disease treatment, transcriptional regulation and genome-wide screening. Despite these exciting achievements, efficient and controlled delivery of the CRISPR/Cas9 system has remained a critical obstacle to its further application. Herein, we elaborate on the three delivery forms of the CRISPR/Cas9 system, and discuss the composition, advantages and limitations of these forms. Then we provide a comprehensive overview of the carriers of the system, and focus on the nonviral nanocarriers in chemical methods that facilitate efficient and controlled delivery of the CRISPR/Cas9 system. Finally, we discuss the challenges and prospects of the delivery methods of the CRISPR/Cas9 system in depth, and propose strategies to address the intracellular and extracellular barriers to delivery in clinical applications.

Stimuli-Responsive Design of Metal-Organic Frameworks for Cancer Theranostics: Current Challenges and Future Perspective

Scientific fraternity revealed the potential of stimuli-responsive nanotherapeutics for cancer treatment that aids in tackling the major restrictions of traditionally reported drug delivery systems. Among stimuli-responsive inorganic nanomaterials, metal-organic frameworks (MOFs) have transpired as unique porous materials displaying resilient structures and diverse applications in cancer theranostics. Mainly, it demonstrates tailorable porosity, versatile chemical configuration, tunable size and shape, and feasible surface functionalization, etc. The present review provides insights into the design of stimuli-responsive multifunctional MOFs for targeted drug delivery and bioimaging for effective cancer therapy. Initially, the concept of cancer, traditional cancer treatment, background of MOFs, and approaches for MOFs synthesis have been discussed. After this, applications of stimuli-responsive multifunctional MOFs-assisted nanostructures that include pH, light, ions, temperature, magnetic, redox, ATP, and others for targeted drug delivery and bioimaging in cancer have been thoroughly discussed. As an outcome, the designed multifunctional MOFs showed an alteration in properties due to the exogenous and endogenous stimuli that are beneficial for drug release and bioimaging. The several reported types of stimuli-responsive surface-modified MOFs revealed good biocompatibility to normal cells, promising drug loading capability, target-specific delivery of anticancer drugs into cancerous cells, etc. Despite substantial progress in this field, certain crucial issues need to be addressed to reap the clinical benefits of multifunctional MOFs. Specifically, the toxicological compatibility and biodegradability of the building blocks of MOFs demand a thorough evaluation. Moreover, the investigation of sustainable and greener synthesis methods is of the utmost importance. Also, the low flexibility, off-target accumulation, and compromised pharmacokinetic profile of stimuli-responsive MOFs have attracted keen attention. In conclusion, the surface-modified nanosized design of inorganic diverse stimuli-sensitive MOFs demonstrated great potential for targeted drug delivery and bioimaging in different kinds of cancers. In the future, the preference for stimuli-triggered MOFs will open a new frontier for cancer theranostic applications.

Synthetic nanoparticles for the delivery of CRISPR/Cas9 gene editing system: classification and biomedical applications

Gene editing has great potential in biomedical research including disease diagnosis and treatment. Clustered regularly interspaced short palindromic repeats (CRISPR) is the most straightforward and cost-effective method. The efficient and precise delivery of CRISPR can impact the specificity and efficacy of gene editing. In recent years, synthetic nanoparticles have been discovered as effective CRISPR/Cas9 delivery vehicles. We categorized synthetic nanoparticles for CRISPR/Cas9 delivery and discribed their advantages and disadvantages. Further, the building blocks of different kinds of nanoparticles and their applications in cells/tissues, cancer and other diseases were described in detail. Finally, the challenges encountered in the clinical application of CRISPR/Cas9 delivery materials were discussed, and potential solutions were provided regarding efficiency and biosafety issues.

A bimetallic nanoplatform for STING activation and CRISPR/Cas mediated depletion of the methionine transporter in cancer cells restores anti-tumor immune responses

Lack of sufficient cytotoxic T lymphocytes (CD8+ T cells) infiltration and dysfunctional state of CD8+ T cells are considered enormous obstacles to antitumor immunity. Herein, we construct a synergistic nanoplatform to promote CD8+ T cell infiltration in tumors while restoring T cell function by regulating methionine metabolism and activating the STING innate immune pathway. The CRISPR/Cas9 system down-regulates the methionine transporter SLC43A2 and restricts the methionine uptake by tumor cells, thereby relieving the methionine competition pressure of T cells; simultaneously, the released nutrition metal ions activate the cGAS/STING pathway. In this work, the described nanoplatform can enhance the effect of immunotherapy in preclinical cancer models in female mice, enhancing STING pathway mediated immunity and facilitating the development of amino acid metabolic intervention-based cancer therapy.

Lactate-Responsive Gene Editing to Synergistically Enhance Macrophage-Mediated Cancer Immunotherapy

Combination therapies involving metabolic regulation and immune checkpoint blockade are considered an encouraging new strategy for cancer therapy. However, the effective utilization of combination therapies for activating tumor-associated macrophages (TAMs) remains challenging. Herein, a lactate-catalyzed chemodynamic approach to activate the therapeutic genome editing of signal-regulatory protein α (SIRPα) to reprogram TAMs and improve cancer immunotherapy is proposed. This system is constructed by encapsulating lactate oxidase (LOx) and clustered regularly interspaced short palindromic repeat-mediated SIRPα genome-editing plasmids in a metal-organic framework (MOF). The genome-editing system is released and activated by acidic pyruvate, which is produced by the LOx-catalyzed oxidation of lactate. The synergy between lactate exhaustion and SIRPα signal blockade can enhance the phagocytic ability of TAMs and promote the repolarization of TAMs to the antitumorigenic M1 phenotype. Lactate exhaustion-induced CD47-SIRPα blockade efficiently improves macrophage antitumor immune responses and effectively reverses the immunosuppressive tumor microenvironment to inhibit tumor growth, as demonstrated by in vitro and in vivo studies. This study provides a facile strategy for engineering TAMs in situ by combining CRISPR-mediated SIRPα knockout with lactate exhaustion for effective immunotherapy.

CRISPR/Cas9 Genome Editing for Tissue-Specific In Vivo Targeting: Nanomaterials and Translational Perspective

Clustered randomly interspaced short palindromic repeats (CRISPRs) and its associated endonuclease protein, i.e., Cas9, have been discovered as an immune system in bacteria and archaea; nevertheless, they are now being adopted as mainstream biotechnological/molecular scissors that can modulate ample genetic and nongenetic diseases via insertion/deletion, epigenome editing, messenger RNA editing, CRISPR interference, etc. Many Food and Drug Administration-approved and ongoing clinical trials on CRISPR adopt ex vivo strategies, wherein the gene editing is performed ex vivo, followed by reimplantation to the patients. However, the in vivo delivery of the CRISPR components is still under preclinical surveillance. This review has summarized the nonviral nanodelivery strategies for gene editing using CRISPR/Cas9 and its recent advancements, strategic points of view, challenges, and future aspects for tissue-specific in vivo delivery of CRISPR/Cas9 components using nanomaterials.

Stimuli-responsive cancer nanomedicines inhibit glycolysis and impair redox homeostasis

The solid tumors are characterized with oxidative stress and metabolic reprogramming, which has been independently used for targeted tumor monotherapy. However, the potential of targeting metabolism-redox circuit in tumor therapy has long been neglected. Herein, we report a hybrid nanocarrier for concurrent targeting of glycolysis and redox balance in the current work. The nanocarriers are made of pH- and ATP-responsive zeolitic imidazolate framework (ZIF-8) as the porous core that was further coated with poloxamer 407 as the steric stabilizer. Two active cargos, glucose oxidase (GOx) and 3-bromopyruvate (3-BrPA) were co-loaded in the core of nanocarrier. GOx is well-known for its ability of producing hydrogen peroxide at the expense of glucose and oxygen. 3-BrPA can reduce oxygen and glucose consumption through glycolysis, which sensitized cancer cells to GOx-induced apoptosis. At the cellular level, the hybrid nanocarrier significantly impaired the redox balance in the liver hepatocellular carcinoma cell line (HepG2), as evidenced by the depletion of glutathione and boost of reactive oxygen species. The potency of hybrid nanocarrier in terms of suppressing HepG2 cell energy metabolism was proven by the exhaustion of ATP. As a consequence, cell viability was greatly reduced. The in vivo efficacy of hybrid nanocarriers was demonstrated in HepG2 tumor-bearing mice. The current work presents an approach of targeting metabolism-redox circuit for tumor treatment, which may enrich the available anti-tumor strategies. STATEMENT OF SIGNIFICANCE: Metabolic alterations and elevated reactive oxygen species (ROS) are two characteristics of cancer. The metabolic patterns of cancer cells are elaborately reprogrammed to enable the rapid propagation of cancer cells. However, the potential of targeting the metabolism-redox circuit in anti-tumor therapy has long been neglected. As a proof-of-concept, we report an engineered stimuli-responsive nanomedicine that can eradicate cancer cells via cooperative glycolysis inhibition and redox impairment. The current work presents an approach of targeting the metabolism-redox circuit for tumor treatment, which may enrich the available anti-tumor strategies.

Metal-Organic Frameworks Facilitate Nucleic Acids for Multimode Synergistic Therapy of Breast Cancer

Compared with traditional medical methods, gene therapy and photodynamic therapy are the new fields of cancer treatment, and they more accurately and effectively obtain preferable therapeutic effects. In this study, a chemotherapy drug-free nanotherapeutic system based on ZIF-90 encapsulated with Ce6-G3139 and Ce6-DNAzyme for gene and photodynamic therapies was constructed. Once entering the cancer cell, the therapy system will decompose and release Zn²⁺, Ce6-G3139, and Ce6-DNAzyme in the acidic environment. On the one hand, G3139 binds to the antiapoptotic gene BCL-2 in tumor cells and downregulates related proteins to inhibit tumor proliferation. On the other hand, Zn²⁺ produced by the decomposition of ZIF-90 can be used as a cofactor to activate the cleavage activity of DNAzyme to initiate gene therapy. Proliferation and metastasis of tumors were further inhibited by DNAzyme, targeting and cutting the gene of human early growth factor-1 (EGR-1). In addition, the photosensitizer Ce6 carried by the nucleic acid will produce cytotoxic ROS to kill cancer cells after irradiation. The results of this study demonstrated that the designed nanoplatform, which synergistically combines gene and photodynamic therapies, has shown great potential for cancer treatment.

Aptamer-Based Point-of-Care Devices: Emerging Technologies and Integration of Computational Methods

Recent innovations in point-of-care (POC) diagnostic technologies have paved a critical road for the improved application of biomedicine through the deployment of accurate and affordable programs into resource-scarce settings. The utilization of antibodies as a bio-recognition element in POC devices is currently limited due to obstacles associated with cost and production, impeding its widespread adoption. One promising alternative, on the other hand, is aptamer integration, i.e., short sequences of single-stranded DNA and RNA structures. The advantageous properties of these molecules are as follows: small molecular size, amenability to chemical modification, low- or nonimmunogenic characteristics, and their reproducibility within a short generation time. The utilization of these aforementioned features is critical in developing sensitive and portable POC systems. Furthermore, the deficiencies related to past experimental efforts to improve biosensor schematics, including the design of biorecognition elements, can be tackled with the integration of computational tools. These complementary tools enable the prediction of the reliability and functionality of the molecular structure of aptamers. In this review, we have overviewed the usage of aptamers in the development of novel and portable POC devices, in addition to highlighting the insights that simulations and other computational methods can provide into the use of aptamer modeling for POC integration.

Pore Size Tunable Trypsin@ZIF-90 and Hydrogel Integrated Lateral Flow Point-of-Care Platform for ATP Detection

The cost-effective, convenient, visible, and equipment-free determination of biomarkers is always the priority development concern of disease diagnosis. The paper-based signal output strategy permits output visual signals without instruments and is regarded as a promising approach with simple operation and low cost. Herein, by varying the addition amount of trypsin, we pioneered a novel enzyme mineralization strategy to construct trypsin@ZIF-90 with tunable porosity properties and catalytic activity. The successful synthesis of trypsin@ZIF-90, which is tagged with T₁, T₃,... (T_x, x is the addition amount of trypsin. Unit: mg), demonstrated the feasibility of this strategy. By serving the constructed trypsin@ZIF-90-T₁ as the target recognition module, and a new designed hydrogel-integrated pH indicator strip as the signal reporter, a point-of-care test (POCT) platform was developed for convenient and equipment-free measurement of adenosine triphosphate (ATP). The enzymatic activity measurement of trypsin@ZIF-90 and concurrently the quantitative analysis of ATP can be favorably realized by simple counting the flow distance and coverage area of water released during the reaction on a pH indicator strip. As a result, this portable platform can enable rapid detection of ATP in the linear range of 20-1500 μM and possesses favorable sensitivity, selectivity, and applicability. Thus, the constructions of tunable frameworks and paper-based POCT are of outstanding significance in the fields of porous metal-organic framework synthesis, enzyme mineralization, and rapid detection for medical diagnostics and environmental monitoring applications.