Chemically Modified Platforms for Better RNA Therapeutics.

RNA-based therapies have catalyzed a revolutionary transformation in the biomedical landscape, offering unprecedented potential in disease prevention and treatment. However, despite their remarkable achievements, these therapies encounter substantial challenges including low stability, susceptibility to degradation by nucleases, and a prominent negative charge, thereby hindering further development. Chemically modified platforms have emerged as a strategic innovation, focusing on precise alterations either on the RNA moieties or their associated delivery vectors. This comprehensive review delves into these platforms, underscoring their significance in augmenting the performance and translational prospects of RNA-based therapeutics. It encompasses an in-depth analysis of various chemically modified delivery platforms that have been instrumental in propelling RNA therapeutics toward clinical utility. Moreover, the review scrutinizes the rationale behind diverse chemical modification techniques aiming at optimizing the therapeutic efficacy of RNA molecules, thereby facilitating robust disease management. Recent empirical studies corroborating the efficacy enhancement of RNA therapeutics through chemical modifications are highlighted. Conclusively, we offer profound insights into the transformative impact of chemical modifications on RNA drugs and delineates prospective trajectories for their future development and clinical integration.

Oral Nanomedicine: Challenges and Opportunities.

Compared to injection administration, oral administration is free of discomfort, wound infection, and complications and has a higher compliance rate for patients with diverse diseases. However, oral administration reduces the bioavailability of medicines, especially biologics (e.g., peptides, proteins, and antibodies), due to harsh gastrointestinal biological barriers. In this context, the development and prosperity of nanotechnology have helped improve the bioactivity and oral availability of oral medicines. On this basis, first, the biological barriers to oral administration are discussed, and then oral nanomedicine based on organic and inorganic nanomaterials and their biomedical applications in diverse diseases are reviewed. Finally, the challenges and potential opportunities in the future development of oral nanomedicine, which may provide a vital reference for the eventual clinical transformation and standardized production of oral nanomedicine, are put forward.

Real-Time Live Imaging of Osteoclast Activation via Cathepsin K Activity in Bone Diseases.

Intravital fluorescence imaging of functional osteoclasts within their intact disease context provides valuable insights into the intricate biology at the microscopic level, facilitating the development of therapeutic approaches for osteoclast-associated bone diseases. However, there is a lack of studies investigating osteoclast activity within deep-seated bone lesions using appropriate fluorescent probes, despite the advantages offered by the multi-photon excitation system in enhancing deep tissue imaging resolution. In this study, we report on the intravital tracking of osteoclast activity in three distinct murine bone disease models. We utilized a cathepsin K (CatK)-responsive two-photon fluorogenic probe (CatKP1), which exhibited a notable fluorescence turn-on response in the presence of active CatK. By utilizing CatKP1, we successfully monitored a significant increase in osteoclast activity in hindlimb long bones and its attenuation through pharmacological intervention without sacrificing mice. Thus, our findings highlight the efficacy of CatKP1 as a valuable tool for unraveling pathological osteoclast behavior and exploring novel therapeutic strategies.

Nanosensitizer-mediated augmentation of sonodynamic therapy efficacy and antitumor immunity.

The dense stroma of desmoplastic tumor limits nanotherapeutic penetration and hampers the antitumor immune response. Here, we report a denaturation-and-penetration strategy and the use of tin monosulfide nanoparticles (SnSNPs) as nano-sonosensitizers that can overcome the stromal barrier for the management of desmoplastic triple-negative breast cancer (TNBC). SnSNPs possess a narrow bandgap (1.18 eV), allowing for efficient electron (e-)-hole (h+) pair separation to generate reactive oxygen species under US activation. More importantly, SnSNPs display mild photothermal properties that can in situ denature tumor collagen and facilitate deep penetration into the tumor mass upon near-infrared irradiation. This approach significantly enhances sonodynamic therapy (SDT) by SnSNPs and boosts antitumor immunity. In mouse models of malignant TNBC and hepatocellular carcinoma (HCC), the combination of robust SDT and enhanced cytotoxic T lymphocyte infiltration achieves remarkable anti-tumor efficacy. This study presents an innovative approach to enhance SDT and antitumor immunity using the denaturation-and-penetration strategy, offering a potential combined sono-immunotherapy approach for the cancer nanomedicine field.

Inhaled mRNA nanoparticles dual-targeting cancer cells and macrophages in the lung for effective transfection.

Messenger RNA (mRNA)-based therapeutics are transforming the landscapes of medicine, yet targeted delivery of mRNA to specific cell types while minimizing off-target accumulation remains challenging for mRNA-mediated therapy. In this study, we report an innovative design of a cationic lipid- and hyaluronic acid-based, dual-targeted mRNA nanoformulation that can display the desirable stability and efficiently transfect the targeted proteins into lung tissues. More importantly, the optimized dual-targeted mRNA nanoparticles (NPs) can not only accumulate primarily in lung tumor cells and inflammatory macrophages after inhalation delivery but also efficiently express any desirable proteins (e.g., p53 tumor suppressor for therapy, as well as luciferase and green fluorescence protein for imaging as examples in this study) and achieve efficacious lung tissue transfection in vivo. Overall, our findings provide proof-of-principle evidence for the design and use of dual-targeted mRNA NPs in homing to specific cell types to up-regulate target proteins in lung tissues, which may hold great potential for the future development of mRNA-based inhaled medicines or vaccines in treating various lung-related diseases.

Nano-bio interactions in mRNA nanomedicine: Challenges and opportunities for targeted mRNA delivery.

Upon entering the biological milieu, nanomedicines swiftly interact with the surrounding tissue fluid, subsequently being enveloped by a dynamic interplay of biomacromolecules, such as carbohydrates, nucleic acids, and cellular metabolites, but with predominant serum proteins within the biological corona. A notable consequence of the protein corona phenomenon is the unintentional loss of targeting ligands initially designed to direct nanomedicines toward particular cells or organs within the in vivo environment. mRNA nanomedicine displays high demand for specific cell and tissue-targeted delivery to effectively transport mRNA molecules into target cells, where they can exert their therapeutic effects with utmost efficacy. In this review, focusing on the delivery systems and tissue-specific applications, we aim to update the nanomedicine population with the prevailing and still enigmatic paradigm of nano-bio interactions, a formidable hurdle in the pursuit of targeted mRNA delivery. We also elucidate the current impediments faced in mRNA therapeutics and, by contemplating prospective avenues-either to modulate the corona or to adopt an 'ally from adversary' approach-aim to chart a course for advancing mRNA nanomedicine.

Infected wound repair with an ultrasound-enhanced nanozyme hydrogel scaffold.

Chronic diabetic wounds persistently face the threat of evolving into diabetic foot ulcers owing to severe hypoxia, high levels of reactive oxygen species (ROS), and a complex inflammatory microenvironment. To concurrently surmount these obstacles, we developed an all-round therapeutic strategy based on nanozymes that simultaneously scavenge ROS, generate O2 and regulate the immune system. First, we designed a dynamic covalent bond hybrid of a metal-organic coordination polymer as a synthesis template, obtaining high-density platinum nanoparticle assemblies (PNAs). This compact assembly of platinum nanoparticles not only effectively simulates antioxidant enzymes (CAT, POD) but also, under ultrasound (US), enhances electron polarization through the surface plasmon resonance effect, endowing it with the ability to induce GSH generation by effectively replicating the enzyme function of glutathione reductase (GR). PNAs, by mimicking the activity of CAT and POD, effectively catalyze hydrogen peroxide, alleviate hypoxia, and effectively generate GSH under ultrasound, further enhancing ROS scavenging. Notably, PNAs can regulate macrophage responses in the inflammatory microenvironment, circumventing the use of any additives. It was confirmed that PNAs can enhance cell proliferation and migration, promote neoangiogenesis IN VITRO, and accelerate the healing of infected diabetic wounds IN VIVO. We believe that an all-round therapeutic method based on PNA nanozymes could be a promising strategy for sustained diabetic wound healing.

In situ Engineering of Tumor-Associated Macrophages via a Nanodrug-Delivering-Drug (ß-Elemene@Stanene) Strategy for Enhanced Cancer Chemo-Immunotherapy.

Tumor-associated macrophages (TAMs) play a critical role in the immunosuppressive solid tumor microenvironment (TME), yet in situ engineering of TAMs for enhanced tumor immunotherapy remains a significant challenge in translational immuno-oncology. Here, we report an innovative nanodrug-delivering-drug (STNSP@ELE) strategy that leverages two-dimensional (2D) stanene-based nanosheets (STNSP) and ß-Elemene (ELE), a small-molecule anticancer drug, to overcome TAM-mediated immunosuppression and improve chemo-immunotherapy. Our results demonstrate that both STNSP and ELE are capable of polarizing the tumor-supportive M2-like TAMs into a tumor-suppressive M1-like phenotype, which acts with the ELE chemotherapeutic to boost antitumor responses. In vivo mouse studies demonstrate that STNSP@ELE treatment can reprogram the immunosuppressive TME by significantly increasing the intratumoral ratio of M1/M2-like TAMs, enhancing the population of CD4+ and CD8+ T lymphocytes and mature dendritic cells, and elevating the expression of immunostimulatory cytokines in B16F10 melanomas, thereby promoting a robust antitumor response. Our study not only demonstrates that the STNSP@ELE chemo-immunotherapeutic nanoplatform has immune-modulatory capabilities that can overcome TAM-mediated immunosuppression in solid tumors, but also highlights the promise of this nanodrug-delivering-drug strategy in developing other nano-immunotherapeutics and treating various types of immunosuppressive tumors.

mRNA-based cancer therapeutics.

Due to the fact that mRNA technology allows the production of diverse vaccines and treatments in a shorter time frame and with reduced expense compared to conventional approaches, there has been a surge in the use of mRNA-based therapeutics in recent years. With the aim of encoding tumour antigens for cancer vaccines, cytokines for immunotherapy, tumour suppressors to inhibit tumour development, chimeric antigen receptors for engineered T cell therapy or genome-editing proteins for gene therapy, many of these therapeutics have shown promising efficacy in preclinical studies, and some have even entered clinical trials. Given the evidence supporting the effectiveness and safety of clinically approved mRNA vaccines, coupled with growing interest in mRNA-based therapeutics, mRNA technology is poised to become one of the major pillars in cancer drug development. In this Review, we present in vitro transcribed mRNA-based therapeutics for cancer treatment, including the characteristics of the various types of synthetic mRNA, the packaging systems for efficient mRNA delivery, preclinical and clinical studies, current challenges and future prospects in the field. We anticipate the translation of promising mRNA-based treatments into clinical applications, to ultimately benefit patients.

Cu(ii)-BODIPY photosensitizer for CAIX overexpressed cancer stem cell therapy.

Chemoresistance originating from cancer stem cells (CSCs) is a major cause of cancer treatment failure and highlights the need to develop CSC-targeting therapies. Although enormous progress in both photodynamic therapy (PDT) and chemodynamic therapy (CDT) has been made in recent decades, the efficacy of these modalities against CSC remains limited. Here, we report a new generation photosensitizer, CA9-BPS-Cu(ii), a system that combines three subunits within a single molecule, namely a copper catalyst for CDT, a boron dipyrromethene photosensitizer for PDT, and acetazolamide for CSC targeting via carbonic anhydrase-9 (CA9) binding. A therapeutic effect in MDA-MB-231 cells was observed that is ascribed to elevated oxidative stress mediated by a combined CDT/PDT effect, as well as through copper-catalysed glutathione oxidation. The CSC targeting ability of CA9-BPS-Cu(ii) was evident from the enhanced affinity of CA9-BPS-Cu(ii) towards CD133-positive MDA-MB-231 cells where CA9 is overexpressed vs. CD133-negative cells. Moreover, the efficacy of CA9-BPS-Cu(ii) was successfully demonstrated in a xenograft mouse tumour model.

Cancer nanomedicine toward clinical translation: Obstacles, opportunities, and future prospects.

With the integration of nanotechnology into the medical field at large, great strides have been made in the development of nanomedicines for tackling different diseases, including cancers. To date, various cancer nanomedicines have demonstrated success in preclinical studies, improving therapeutic outcomes, prolonging survival, and/or decreasing side effects. However, the translation from bench to bedside remains challenging. While a number of nanomedicines have entered clinical trials, only a few have been approved for clinical applications. In this review, we highlight the most recent progress in cancer nanomedicine, discuss current clinical advances and challenges for the translation of cancer nanomedicines, and provide our viewpoints on accelerating clinical translation. We expect this review to benefit the future development of cancer nanotherapeutics specifically from the clinical perspective.

Real-Time Fluorescence Screening Platform for Meat Freshness.

Meat's freshness is closely related to food safety and human health and has received increasing attention nowadays. To on-site visually screen meat freshness in a fast and non-destructive manner, we rationally constructed a series of fluorescent probes (JDCN, JDNS, and JDPY) with distinct electron-withdrawing substitution groups based on julolidine-fused coumarin. These probes underwent an aza-Michael addition followed by an elimination reaction with cadaverine to generate a colorimetric and ratiometric fluorescence response, and their sensing performance was rationally enhanced by improving the electron-withdrawing strength of substitution groups. Particularly, JDCN with a dicyanovinyl group as the reaction site exhibited outstanding sensing performance including rapid response (∼60 s), high selectivity, and low detection limit (14 nM). Furthermore, JDCN was fabricated into test kits to detect cadaverine vapor with a high-contrast fluorescence change from red to green. Based on two-color visualization of cadaverine vapor, on-site non-contact and non-destructive monitoring of meat freshness was successfully achieved. The good sensing performance rendered JDCN test kits a promising real-time fluorescence screening platform for rapid, non-destructive, and accurate evaluation of meat freshness.

A molecular recognition platform for the simultaneous sensing of diverse chemical weapons.

Chemical warfare agents (CWAs) such as phosgene and nerve agents pose serious threats to our lives and public security, but no tools can simultaneously screen multiple CWAs in seconds. Here, we rationally designed a robust sensing platform based on 8-cyclohexanyldiamino-BODIPY (BODIPY-DCH) to monitor diverse CWAs in different emission channels. Trans-cyclohexanyldiamine as the reactive site provides optimal geometry and high reactivity, allowing trans-BODIPY-DCH to detect CWAs with a quick response and high sensitivity, while cis-BODIPY-DCH has much weaker reactivity to CWAs due to intramolecular H-bonding. Upon reaction with phosgene, trans-BODIPY-DCH was rapidly converted to imidazolone BODIPY (<3 s), triggering green fluorescence with good sensitivity (LOD = 0.52 nM). trans-BODIPY-DCH coupled with nerve agent mimics, affording a blue fluorescent 8-amino-BODIPY tautomer. Furthermore, a portable test kit using trans-BODIPY-DCH displayed an instant response and low detection limits for multiple CWAs. This platform enables rapid and highly sensitive visual screening of various CWAs.

Harnessing GLUT1-Targeted Pro-oxidant Ascorbate for Synergistic Phototherapeutics.

Despite extensive efforts to realize effective photodynamic therapy (PDT), there is still a lack of therapeutic approaches concisely structured to mitigate the major obstacles of PDT in clinical applications. Herein, we report a molecular strategy exploiting ascorbate chemistry to enhance the efficacy of PDT in cancer cells overexpressing glucose transporter 1 (GLUT1). AA-EtNBS, a 5-O-substituted ascorbate-photosensitizer (PS) conjugate, undergoes a reversible structural conversion of the ascorbate moiety in the presence of reactive oxygen species (ROS) and glutathione (GSH), thereby promoting its uptake in GLUT1-overexpressed KM12C colon cancer cells and perturbing tumor redox homeostasis, respectively. Due to the unique pro-oxidant role of ascorbate in tumor environments, AA-EtNBS effectively sensitized KM12C cancer cells prior to PS-mediated generation of superoxide radicals under near-infrared (NIR) illumination. AA-EtNBS successfully exhibited GLUT1-targeted synergistic therapeutic efficacy during PDT both in vitro and in vivo. Therefore, this study outlines a promising strategy employing ascorbate both as a targeting unit for GLUT1-overexpressed cancer cells and redox homeostasis destruction agent, thereby enhancing therapeutic responses towards anticancer treatment when used in conjunction with conventional PDT.

Versatile Types of Inorganic/Organic NIR-IIa/IIb Fluorophores: From Strategic Design toward Molecular Imaging and Theranostics.

In vivo imaging in the second near-infrared window (NIR-II, 1000-1700 nm), which enables us to look deeply into living subjects, is producing marvelous opportunities for biomedical research and clinical applications. Very recently, there has been an upsurge of interdisciplinary studies focusing on developing versatile types of inorganic/organic fluorophores that can be used for noninvasive NIR-IIa/IIb imaging (NIR-IIa, 1300-1400 nm; NIR-IIb, 1500-1700 nm) with near-zero tissue autofluorescence and deeper tissue penetration. This review provides an overview of the reports published to date on the design, properties, molecular imaging, and theranostics of inorganic/organic NIR-IIa/IIb fluorophores. First, we summarize the design concepts of the up-to-date functional NIR-IIa/IIb biomaterials, in the order of single-walled carbon nanotubes (SWCNTs), quantum dots (QDs), rare-earth-doped nanoparticles (RENPs), and organic fluorophores (OFs). Then, these novel imaging modalities and versatile biomedical applications brought by these superior fluorescent properties are reviewed. Finally, challenges and perspectives for future clinical translation, aiming at boosting the clinical application progress of NIR-IIa and NIR-IIb imaging technology are highlighted.

Mitochondrial H2Sn-Mediated Anti-Inflammatory Theranostics.

The insistent demand for space-controllable delivery, which reduces the side effects of non-steroidal anti-inflammatory drugs (NSAIDs), has led to the development of a new theranostics-based approach for anti-inflammatory therapy. The current anti-inflammatory treatments can be improved by designing a drug delivery system responsive to the inflammatory site biomarker, hydrogen polysulfide (H2Sn). Here, we report a novel theranostic agent 1 (TA1), consisting of three parts: H2Sn-mediated triggering part, a two-photon fluorophore bearing mitochondria targeting unit (Rhodol-TPP), and anti-inflammatory COX inhibitor (indomethacin). In vitro experiments showed that TA1 selectively reacts with H2Sn to concomitantly release both Rhodol-TPP and indomethacin. Confocal-microscopy imaging of inflammation-induced live cells suggested that TA1 is localized in the mitochondria where the H2Sn is overexpressed. The TA1 reacted with H2Sn in the endogenous and exogenous H2Sn environments and in lipopolysaccharide treated inflammatory cells. Moreover, TA1 suppressed COX-2 level in the inflammatory-induced cells and prostaglandin E2 (PGE2) level in blood serum from inflammation-induced mouse models. In vivo experiments with inflammation-induced mouse models suggested that TA1 exhibits inflammation-site-elective drug release followed by significant therapeutic effects, showing its function as a theranostic agent, capable of both anti-inflammatory therapy and precise diagnosis. Theranostic behavior of TA1 is highly applicable in vivo model therapeutics for the inflammatory disease.

Harnessing α-l-fucosidase for in vivo cellular senescence imaging.

Precise detection of cellular senescence may allow its role in biological systems to be evaluated more effectively, while supporting studies of therapeutic candidates designed to evade its detrimental effect on physical function. We report here studies of α-l-fucosidase (α-fuc) as a biomarker for cellular senescence and the development of an α-fuc-responsive aggregation induced emission (AIE) probe, termed QM-NHαfuc designed to complement more conventional probes based on ß-galactosidase (ß-gal). Using QM-NHαfuc, the onset of replicative-, reactive oxygen species (ROS)-, ultraviolet A (UVA)-, and drug-induced senescence could be probed effectively. QM-NHαfuc also proved capable of identifying senescent cells lacking ß-gal expression. The non-invasive real-time senescence tracking provided by QM-NHαfuc was validated in an in vivo senescence model. The results presented in this study lead us to suggest that the QM-NHαfuc could emerge as a useful tool for investigating senescence processes in biological systems.

An Ethacrynic Acid-Brominated BODIPY Photosensitizer (EA-BPS) Construct Enhances the Lethality of Reactive Oxygen Species in Hypoxic Tumor-Targeted Photodynamic Therapy.

Despite being a clinically approved intervention for cancer, photodynamic therapy (PDT) still suffers from limitations. Prime among these is a therapeutic response that is mostly oxygen dependent. This limits the utility of PDT in treating hypoxic tumors since lower levels of cytotoxic reactive oxygen species (ROS) are generated in regions of low oxygen tension. Glutathione-pi (GST-pi) is a key enzyme that militates against ROS-mediated apoptosis. We report herein a new construct, EA-BPS, that contains both a brominated BODIPY photosensitizer (BPS) and an ethacrynic acid (EA) GST-pi inhibitor. Photoirradiation of EA-BPS induces a synergistic antitumor effect that results from the combination of ROS production and GST-pi inhibition. Relative to BPS alone, an enhanced cell-killing effect is seen under hypoxic conditions both in vitro and in vivo. We conclude that by making better use of the available oxygen in tumor environments, improved therapeutic PDT outcomes should be achievable even under hypoxic conditions.