Stimuli-responsive nanocarriers for drug delivery, tumor imaging, therapy and theranostics

Drug-device-field integration for mitochondria-targeting dysfunction and tumor therapy by home-tailored pyroelectric nanocomposites

In spite of the hypoxia tumor microenvironment, an efficacious treatment with minimal invasiveness is highly desirable. Among common cellular organelles, mitochondria is a common target for inductive cellular apoptosis and tumor proliferation inhibition. Nevertheless, tumor hypoxic circumstances always give rise to poor therapeutic efficiency and instead lead to lesion recurrence and unsatisfactory prognosis. Herein, a home-tailored pyroelectric nanocomposites of BTO@PDA-FA-DOX-EGCG have been developed via a layer-by-layer synthesis to serve a cutting-edge tumor treatment with specific mitochondria-targeting, hypoxia-relieving, chemo-photodynamic performance and high anti-tumor efficacy. In particular, this therapeutic modality is featured as drug-device-field integration (DDFI) by combining chemo-drugs of DOX and EGCG, a commercially available medical laser and physical pyroelectric fields, which synergistically contributed to continuing ROS production and consequently cell apoptosis and tumor growth inhibition. Meanwhile, an anti-tumor mechanism of immune actuation and mitochondria dysfunction was elucidated by analyzing specific biomarkers of mitochondria complexes and MMPs, and therefore this research opened up a potential pathway for advanced tumor treatment by incorporating nanocomposites, medical devices and physical fields in a DDFI manner.

Double-targeted liposomes coated with matrix metallopeptidase-2-responsive polypeptide nanogel for chemotherapy and enhanced immunotherapy against cervical cancer

Immunotherapy is a cornerstone in cancer treatment, celebrated for its precision, ability to eliminate residual cancer cells, and potential to avert tumor recurrence. Nonetheless, its effectiveness is frequently undermined by the immunosuppressive milieu created by tumors. This study presents a novel nanogel-based drug delivery system, DOX-4PI@CpG@Lipo@Gel (DPCLG), engineered to respond to Matrix Metallopeptidase-2 (MMP-2)-a protease abundant in the tumor microenvironment (TME). This system enables the controlled release of two distinct types of liposomes within the TME. The first, DOX-4PI@Liposome (DPL), carries doxorubicin (DOX) and 4-phenylimidazole (4PI), targeting cancer cells to provide chemotherapeutic effects while diminishing the immunosuppressive environment. The second, a mannosyl-modified cationic liposome (CL), is loaded with Cytosine phosphate guanine (CpG) oligodeoxynucleotides to specifically target M2 phenotype macrophages, reversing their tumor-associated phenotype (TAM) and activating immune cytokines to promote tumor destruction. Our findings indicate that DPCLG significantly curtails tumor growth, both in vitro and in vivo, mitigates the immunosuppressive TME, and triggers a potent systemic immune response. This study underscores the potential of DPCLG as an advanced, dual-targeting drug delivery system for comprehensive cancer therapy.

Oral cancer stem cells: A comprehensive review of key drivers of treatment resistance and tumor recurrence

Oral squamous cell carcinoma (OSCC) remains a major cause of morbidity and mortality worldwide with high recurrence rates and resistance to conventional therapies. Recent studies have highlighted the pivotal role of oral cancer stem cells (OCSCs) in driving treatment resistance and tumor recurrence. OCSCs possess unique properties, including self-renewal, differentiation potential, and resistance to chemotherapy and radiotherapy, which contribute to their ability to survive treatment and initiate tumor relapse. Several signaling pathways, such as Wnt/β-catenin, Hedgehog, Notch, and PI3K/Akt/mTOR, have been implicated in maintaining OCSC properties, promoting survival, and conferring resistance. Additionally, mechanisms such as drug efflux, enhanced DNA repair, epithelial-mesenchymal transition (EMT), and resistance to apoptosis further contribute to resilience. Targeting these pathways offers promising therapeutic strategies for eliminating OCSCs and improving treatment outcomes. Approaches such as immunotherapy, nanotechnology-based drug delivery, and targeting of the tumor microenvironment are emerging as potential solutions to overcome OCSC-mediated resistance. However, further research is needed to fully understand the molecular mechanisms governing OCSCs and develop effective therapies to prevent tumor recurrence. This review discusses the role of OCSCs in treatment resistance and recurrence and highlights the current and future directions for targeting these cells in OSCC.

Supramolecular Assemblies via Host-Guest Interactions for Tumor Immunotherapy

Cancer immunotherapy has emerged as one of the most promising modalities for cancer treatment providing hopes of cancer patients with the significant advantages over traditional antitumor therapy methods. Supramolecular assemblies based on host-guest interactions have been widely explored in the field of cancer immunotherapy as the delivery systems. A variety of supramolecular materials show unique features for efficient drug encapsulation, targeting delivery and release, which are favorable to activate antitumor immune responses especially through combination of different treatment strategies. In this review article, we summarize the research progresses of supramolecular assemblies via host-guest interactions for tumor immunotherapy. The construction of various drug delivery systems including hydrogels, liposomes, and polymeric nanoparticles, the drug encapsulation and delivery, as well as advantages and disadvantages are discussed. The perspectives related to future developments in this field are also described.

Res@ZIF-90 suppress gastric cancer progression by disturbing mitochondrial homeostasis

BACKGROUND

Gastric cancer (GC) is still a serious threat to human health worldwide. As a natural compound, resveratrol has been proven to have anti-tumor activity, and the nano-delivery carrier has shown its excellent ability to retain and control drug release.

METHODS

Res@ZIF-90 underwent synthesis via a one-pot method and subsequent characterization encompassing Dynamic Light Scattering, Scanning Electron Microscope, Transmission Electron Microscope, and UV-vis absorption spectroscope. The release of resveratrol from Res@ZIF-90 across varied pH environments were delineated employing High Performance Liquid Chromatography. The mitochondrial targeting of Res@ZIF-90 was scrutinized utilizing Fluorescent Inverted Microscopy. The cytotoxic impact of Res@ZIF-90 on HGC-27 cells was evaluated through CCK-8 assay, Live/Dead staining, scratch test, and JC-1 assay. Furthermore, the HGC-27 tumor-bearing mice model was established to explore the anti-tumor effect of Res@ZIF-90.

RESULTS

ZIF-90 can effectively release resveratrol under acidic (pH = 5.5) conditions. In addition, Res@ZIF-90 could be taken up by cells and localized into mitochondria. ZIF-90 has no obvious cytotoxicity at the experimental concentration, while Res@ZIF-90 was more cytotoxic to HGC-27 cells than free resveratrol at the same concentration. Res@ZIF-90 significantly reduced the expressions of PGCS 1α, TFAM, PINK1, and COX IV, which together induced mitochondrial homeostasis disorders and inhibited the tumor growth of HGC-27 tumor-bearing mice in vivo.

CONCLUSIONS

Res@ZIF-90 can inhibit the progression of gastric cancer by targeting the mitochondria of gastric cancer cells and disrupting mitochondrial homeostasis to produce cytotoxic effects. Res@ZIF-90 may be a promising antitumor drug with potential application value.

Advances of Stimuli-Responsive Amphiphilic Copolymer Micelles in Tumor Therapy

Amphiphilic copolymers are composed of both hydrophilic and hydrophobic chains, which can self-assemble into polymeric micelles in aqueous solution via the hydrophilic/hydrophobic interactions. Due to their unique properties, polymeric micelles have been widely used as drug carriers. Poorly soluble drugs can be covalently attached to polymer chains or non-covalently incorporated in the micelles, with improved pharmacokinetic profiles and enhanced efficacy. In recent years, stimuli-responsive amphiphilic copolymer micelles have attracted significant attention. These micelles can respond to specific stimuli, including physical triggers (light, temperature, etc). chemical stimuli (pH, redox, etc). and physiological factors (enzymes, ATP, etc). Under these stimuli, the structures or properties of the micelles can change, enabling targeted therapy and controlled drug release in tumors. These stimuli-responsive strategies offer new avenues and approaches to enhance the tumor efficacy and reduce drug side effects. We will review the applications of different types of stimuli-responsive amphiphilic copolymer micelles in tumor therapy, aiming to provide valuable guidance for future research directions and clinical translation.

Reprint of: M1 macrophage-targeted curcumin nanocrystals with l-arginine-modified for acute lung injury by inhalation

Acute Lung Injury/Acute Respiratory Distress Syndrome (ALI/ARDS) with clinical manifestations of respiratory distress and hypoxemia remains a significant cause of respiratory failure, boasting a persistently high incidence and mortality rate. Given the central role of M1 macrophages in the pathogenesis of acute lung injury (ALI), this study utilized the anti-inflammatory agent curcumin as a model drug. l-arginine (L-Arg) was employed as a targeting ligand, and chitosan was initially modified with l-arginine. Subsequently, it was utilized as a surface modifier to prepare inhalable nano-crystals loaded with curcumin (Arg-CS-Cur), aiming for specific targeting of pulmonary M1 macrophages. Compared with unmodified chitosan-curcumin nanocrystals (CS-Cur), Arg-CS-Cur exhibited higher uptake in vitro by M1 macrophages, as evidenced by flow cytometry showing the highest fluorescence intensity in the Arg-CS-Cur group (P < 0.01). In vivo accumulation was greater in inflamed lung tissues, as indicated by small animal imaging demonstrating higher lung fluorescence intensity in the DiR-Arg-CS-Cur group compared to the DiR-CS-Cur group in the rat ALI model (P < 0.05), peaking at 12 h. Moreover, Arg-CS-Cur demonstrated enhanced therapeutic effects in both LPS-induced RAW264.7 cells and ALI rat models. Specifically, treatment with Arg-CS-Cur significantly suppressed NO release and levels of TNF-α and IL-6 in RAW264.7 cells (p < 0.01), while in ALI rat models, expression levels of TNF-α and IL-6 in lung tissues were significantly lower than those in the model group (P < 0.01). Furthermore, lung tissue damage was significantly reduced, with histological scores significantly lower than those in the CS-Cur group (P < 0.01). In conclusion, these findings underscore the targeting potential of l-arginine-modified nanocrystals, which effectively enhance curcumin concentration in inflammatory environments by selectively targeting M1 macrophages. This study thus introduces novel perspectives and theoretical support for the development of targeted therapeutic interventions for acute inflammatory lung diseases, including ALI/ARDS.

Engineering Stimuli-Responsive Materials for Precision Medicine

Over the past decade, precision medicine has garnered increasing attention, making significant strides in discovering new therapeutic drugs and mechanisms, resulting in notable achievements in symptom alleviation, pain reduction, and extended survival rates. However, the limited target specificity of primary drugs and inter-individual differences have often necessitated high-dosage strategies, leading to challenges such as restricted deep tissue penetration rates and systemic side effects. Material science advancements present a promising avenue for these issues. By leveraging the distinct internal features of diseased regions and the application of specific external stimuli, responsive materials can be tailored to achieve targeted delivery, controllable release, and specific biochemical reactions. This review aims to highlight the latest advancements in stimuli-responsive materials and their potential in precision medicine. Initially, we introduce disease-related internal stimuli and capable external stimuli, elucidating the reaction principles of responsive functional groups. Subsequently, we provide a detailed analysis of representative pre-clinical achievements of stimuli responsive materials across various clinical applications, including enhancements in the treatment of cancers, injury diseases, inflammatory diseases, infection diseases, and high-throughput microfluidic biosensors. Finally, we discuss some clinical challenges, such as off-target effects, long-term impacts of nano-materials, potential ethical concerns, and offer insights into future perspectives of stimuli-responsive materials.

Combining functionalities-nanoarchitectonics for combatting bacterial infection

New antimicrobial and anti-inflammatory therapeutics are needed because of antibiotic resistance development and resulting complications such as inflammation, ultimately leading to septic shock. The antimicrobial effects of various nanoparticles (NPs) are currently attracting intensive research interest. Although various NPs display potent antimicrobial effects against strains resistant to conventional antibiotics, the therapeutic use of such materials is restricted by poor selectivity between bacteria and human cells, leading to adverse side effects. As a result, increasing research efforts during the last few years have focused on targeting NPs against bacteria and other components in the infection micro-environment. Examples of approaches explored include peptide-, protein- and nucleic acid-based NP coatings for bacterial membrane recognition, as well as NP conjugation with enzyme substrates or other moieties that respond to bacterial or other enzymes present in the infection micro-environment. In general, this study aims to add to the literature on the antimicrobial effects of nanomaterials by discussing surface modification strategies for targeting bacterial membranes and membrane components, as well as how such surface modifications can improve the antimicrobial effects of nanomaterials and simultaneously decrease toxicity towards human cells and tissues. In doing so, the biological effects observed are related throughout to the physico-chemical modes of action underlying such effects.

Ultrasound-triggered drug release in vivo from antibubble-loaded macrophages

Nanoparticles have proven to be attractive carriers in therapeutic drug delivery since they can encapsulate, protect and stabilize a plethora of different drugs, thereby improving therapeutic efficacy and reducing side effects. However, specific targeting of drug-loaded nanoparticles to the tissue of interest and a timely and spatially controlled release of drugs on demand still represent a challenge. Recently, gas-filled microparticles, so-called antibubbles, have been developed which can efficiently encapsulate liquid drug droplets. Here, we show that antibubbles are efficiently taken up by macrophages in vitro and are stably maintained for more than 48 h without compromising antibubble integrity and macrophage viability. We show that application of diagnostic ultrasound induces the disintegration of both antibubbles and carrier cells while not affecting non-loaded macrophages. Using 4-hydroxytamoxifen as a model drug, we show ultrasound-mediated drug release upon adoptive transfer of antibubble-loaded macrophages in mice. Together with the ability of macrophages to accumulate in inflamed tissues, antibubble-loaded macrophages represent an attractive tool for targeted delivery of drugs and its ultrasound-mediated spatial and temporal drug release, highlighting the therapeutic perspective of this strategy.

Photothrombolytics: A light-driven technology for the targeted lysis of thrombi

Occlusive blood clots remain a significant global health challenge and result in emergencies that are main causes of death and disability worldwide. Thrombolytic agents (including tissue plasminogen activator, tPA) are the only pharmacological means to dissolve blood clots. However, these drugs have modest efficacy and severe safety concerns persist. We have developed light-responsive tPA-loaded red blood cells (tPA-RBCsPhoto) to target thrombolytic activity at the site of a blood clot. Herein, we describe the use of light to control the release of tPA from engineered RBCs and the subsequent degradation of a blood clot ex vivo. Furthermore, we have employed this technology to restore blood flow to an occluded mouse artery in vivo using a targeted dose that is 25 times lower than conventional systemic tPA treatment.

Overcoming Challenges in Small-Molecule Drug Bioavailability: A Review of Key Factors and Approaches

The bioavailability of small-molecule drugs remains a critical challenge in pharmaceutical development, significantly impacting therapeutic efficacy and commercial viability. This review synthesizes recent advances in understanding and overcoming bioavailability limitations, focusing on key physicochemical and biological factors influencing drug absorption and distribution. We examine cutting-edge strategies for enhancing bioavailability, including innovative formulation approaches, rational structural modifications, and the application of artificial intelligence in drug design. The integration of nanotechnology, 3D printing, and stimuli-responsive delivery systems are highlighted as promising avenues for improving drug delivery. We discuss the importance of a holistic, multidisciplinary approach to bioavailability optimization, emphasizing early-stage consideration of ADME properties and the need for patient-centric design. This review also explores emerging technologies such as CRISPR-Cas9-mediated personalization and microbiome modulation for tailored bioavailability enhancement. Finally, we outline future research directions, including advanced predictive modeling, overcoming biological barriers, and addressing the challenges of emerging therapeutic modalities. By elucidating the complex interplay of factors affecting bioavailability, this review aims to guide future efforts in developing more effective and accessible small-molecule therapeutics.

Nanotherapy therapy for acute respiratory distress syndrome: a review

Acute respiratory distress syndrome (ARDS) is a complex and life-threatening disease characterized by severe respiratory failure. The lethality of ARDS remains alarmingly high, especially with the persistent ravages of coronavirus disease 2019 (COVID-19) in recent years. ARDS is one of the major complications of neocoronavirus pneumonia and the leading cause of death in infected patients. The large-scale outbreak of COVID-19 has greatly increased the incidence and mortality of ARDS. Despite advancements in our understanding of the causes and mechanisms of ARDS, the current clinical practice is still limited to the use of supportive medications to alleviate its progression. However, there remains a pressing need for effective therapeutic drugs to combat this devastating disease. In this comprehensive review, we discuss the commonly used therapeutic drugs for ARDS, including steroids, vitamin C, targeted inhibitors, and heparin. While these medications have shown some promise in managing ARDS, there is still a significant gap in the availability of definitive treatments. Moreover, we highlight the potential of nanocarrier delivery systems, such as liposomes, lipid nanoparticles, polymer nanoparticles, and inorganic nanoparticles, as promising therapeutic approaches for ARDS in the future. These innovative delivery systems have demonstrated encouraging results in early clinical trials and offer the potential for more targeted and effective treatment options. Despite the promising early results, further clinical trials are necessary to fully assess the efficacy and safety of nanotherapies for ARDS. Additionally, more in-depth research should be conducted to focus on the continuous development of precision therapies targeting different stages of ARDS development or different triggers. This will provide more ideas and rationale for the treatment of ARDS and ultimately lead to better patient outcomes.

Advances and prospects of precision nanomedicine in personalized tumor theranostics

Tumor, as the second leading cause of death globally, following closely behind cardiovascular diseases, remains a significant health challenge worldwide. Despite the existence of various cancer treatment methods, their efficacy is still suboptimal, necessitating the development of safer and more efficient treatment strategies. Additionally, the advancement of personalized therapy offers further possibilities in cancer treatment. Nanomedicine, as a promising interdisciplinary field, has shown tremendous potential and prospects in the diagnosis and treatment of cancer. As an emerging approach in oncology, the application of nanomedicine in personalized cancer therapy primarily focuses on targeted drug delivery systems such as passive targeting drug delivery, active targeting drug delivery, and environmentally responsive targeting drug delivery, as well as imaging diagnostics such as tumor biomarker detection, tumor cell detection, and in vivo imaging. However, it still faces challenges regarding safety, biocompatibility, and other issues. This review aims to explore the advances in the use of nanomaterials in the field of personalized cancer diagnosis and treatment and to investigate the prospects and challenges of developing personalized therapies in cancer care, providing direction for the clinical translation and application.

Stimuli-Responsive NO Delivery Platforms for Bacterial Infection Treatment

The prevalence of drug-resistant bacterial infections has emerged as a grave threat to clinical treatment and global human health, presenting one of the foremost challenges in medical care. Thus, there is an urgent imperative to develop safe and efficacious novel antimicrobial strategies. Nitric oxide (NO) is a recognized endogenous signaling molecule, which plays a pivotal role in numerous pathological processes. Currently, NO has garnered significant interest as an antibacterial agent due to its capability to eradicate bacteria, disrupt biofilms, and facilitate wound healing, all while circumventing the emergence of drug resistance. However, the inherently unstable characteristic of NO therapeutic gas renders the controlled administration of NO gases exceedingly challenging. Hence, in this review, the current challenge of bacterial infection is discussed; then it is briefly elucidated the antibacterial mechanism of NO and comprehensively delineate the recent advancements in stimulus-responsive NO delivery platforms, along with their merits, obstacles, and prospective avenues for clinical application. This review offers guidance for future advancements in NO-medicated anti-infection therapy is hoped.

Potential of a CO2-Responsive supramolecular drug-carrier system as a safer and more effective treatment for cancer

We combined carbon dioxide (CO2)-responsive cytosine-containing rhodamine 6G (Cy-R6G) as a hydrophobic anticancer agent with hydrogen-bonded cytosine-functionalized polyethylene glycol (Cy-PEG) as a hydrophilic supramolecular carrier to construct a CO2-responsive drug delivery system, with the aim of enhancing the responsiveness of the system to the tumor microenvironment and thus the overall effectiveness of anticancer therapy. Due to self-complementary hydrogen bonding interactions between cytosine units, Cy-R6G and Cy-PEG co-assemble in water to form spherical-like nanogels, with Cy-R6G effectively encapsulated within the nanogels. The nanogels exhibit several distinctive physical features, such as widely tunable nanogel size and drug loading capacity for Cy-R6G, intriguing fluorescence properties, high co-assembled structural stability in normal aqueous environments, enhanced anti-hemolytic characteristics, sensitive dual CO2/pH-responsive behavior, and precise and easily controllable CO2-induced release of Cy-R6G. Cytotoxicity assays clearly indicated that, due to the presence of cytosine receptors on the surface of cancer cells, Cy-R6G-loaded nanogels exert selective cytotoxicity against cancer cells in pristine culture medium, but do not affect the viability of normal cells. Surprisingly, in CO2-rich culture medium, Cy-R6G-loaded nanogels exhibit a further significant enhancement in cytotoxicity against cancer cells, and remain non-cytotoxic to normal cells. More importantly, a series of in vitro experiments demonstrated that compared to pristine culture medium, CO2-rich culture medium promotes more rapid selective internalization of Cy-R6G-loaded nanogels into cancer cells through cytosine-mediated macropinocytosis and thus accelerates the induction of apoptosis. Therefore, this newly developed system provides novel avenues for the development of highly effective CO2-responsive drug delivery systems with potent anticancer capabilities.

Vesicle-based formulations for pain treatment: a narrative review

Pain, a complex and debilitating condition, necessitates innovative therapeutic strategies to alleviate suffering and enhance patients' quality of life. Vesicular systems hold the potential to enhance precision of drug localisation and release, prolong the duration of therapeutic action and mitigate adverse events associated with long-term pharmacotherapy. This review critically assesses the current state-of-the-art in vesicle-based formulations (liposomes, polymersomes, ethosomes, and niosomes) for pain management applications. We highlight formulation engineering strategies used to optimise drug pharmacokinetics, present preclinical findings of experimental delivery systems, and discuss the clinical evidence for the benefits of clinically approved formulations. We present the challenges and outlook for future improvements in long-acting anaesthetic and analgesic formulation development.

Valence-Transforming O2-Depleting Nano-Assembly Enable In Situ Tumor Depositional Embolization

Abnormal metabolism and blood supply/O2 imbalance in tumor cells affect drug transport delivery and increase the difficulty of tumor treatment. Controlling tumor growth by inhibiting tumor cell metabolism and regulating progressive embolization in the tumor region provides an innovative basis for constructing tumor therapeutic models. A highly biocompatible and efficient O2-depleting agent has been investigated to enable in situ precipitation and embolization within the tumor microenvironment. In situ deformation embolizer, Fe-GA@CaCO3 nano-assembly (GA: gallic acid), can convert into the large granular size embolization components of Fe(III) precipitates and affluent Ca2+ within the tumor microenvironment. In situ progressive O2 depletion produces Fe(III) precipitates that embolize tumor regions, isolating O2 and nutrients by blocking supply. Meanwhile, affluent Ca2+ acts on the intracellular, causing mitochondrial dysfunction through calcium overload and contributing to irreversible tumor cell damage. Both internal and external routes work synergistically to produce precise functional inhibition of tumors from the inside out, simultaneously responding to both intracellular and the corresponding tumor regions, providing an innovative solution for anti-tumor therapy.

Enhanced gene transfection ability of sulfonylated low-molecular-weight PEI and its application in anti-tumor treatment

With the continuous progress of nanotechnology in the field of tumor vaccines, immunotherapy has been regarded as one of the most powerful approaches for cancer treatment. Currently, DNA vaccines are used to efficiently deliver plasmids encoding tumor-associated antigens to antigen-presenting cells (APCs) and enhance the activation of immune cells. In this work, a series of aromatic sulfonyl small-molecule-modified polymers R-P based on low-molecular-weight polyethylenimine (PEI) were prepared, and their structure-activity relationship was studied. Among them, Ns-P with high transfection efficiency and low toxicity was applied to deliver antigen ovalbumin (OVA)-encoded plasmid DNA to APCs for triggering the immune activation of dendritic cells (DCs). It was also found that Ns-P could be used as an immune adjuvant to activate the STING pathway in DCs, integrating innate stimulating activity into the carrier to enhance antitumor immunity. Moreover, the modification of Ns-P/pOVA complexes with oxidized mannan could not only improve the biocompatibility of the complex, but also enhance the uptake of DCs, further inducing OVA antigen presentation and immune stimulation. In vivo antitumor assays indicated that Ns-P/pOVA/Man immunization could inhibit the growth of OVA-expressing E.G7 tumors in C57BL/6 mice. These results demonstrated that Ns-P/pOVA/Man is promising for gene delivery and immunotherapy application.

Vesicles: New Advances in the Treatment of Neurodegenerative Diseases

Neurodegenerative diseases are characterized by brain lesions that limit normal daily activities and represent a major challenge to healthcare systems worldwide, with a significant economic impact. Nanotechnology is the science of manipulating matter at the nanoscale, where materials exhibit unique properties that are significantly different from their larger counterparts. These properties can be exploited for a wide range of applications, including medicine. Among the emerging therapeutic approaches for the treatment of neurodegenerative diseases, nanotechnologies are gaining prominence as a promising avenue to explore. Here, we review the state of the art of biological and artificial vesicles and their biological properties in the context of neurodegenerative diseases. Indeed, nanometric structures such as extracellular vesicles and artificial vesicles represent a promising tool for the treatment of such disorders due to their size, biocompatibility, and ability to transport drugs, proteins, and genetic material across the blood-brain barrier to target specific cells and brain areas. In the future, a deeper and broader synergy between materials science, bioengineering, biology, medicine, and the discovery of new, increasingly powerful delivery systems will certainly enable a more applied use of nanotechnology in the treatment of brain disorders.

Development of citric acid-based biomaterials for biomedical applications

The development of bioactive materials with controllable preparation is of great significance for biomedical engineering. Citric acid-based biomaterials are one of the few bioactive materials with many advantages such as simple synthesis, controllable structure, biocompatibility, biomimetic viscoelastic mechanical behavior, controllable biodegradability, and further functionalization. In this paper, we review the development of multifunctional citrate-based biomaterials for biomedical applications, and summarize their multifunctional properties in terms of physical, chemical, and biological aspects, and finally the applications of citrate-based biomaterials in biomedical engineering, including bone tissue engineering, skin tissue engineering, drug/cell delivery, vascular and neural tissue engineering, and bioimaging.

Integrin-Specific Stimuli-Responsive Nanomaterials for Cancer Theranostics

Background: Cancer is one of the leading causes of death worldwide. The tumor microenvironment makes the tumor difficult to treat, favoring drug resistance and the formation of metastases, resulting in death. Methods: Stimuli-responsive nanoparticles have shown great capacity to be used as a powerful strategy for cancer treatment, diagnostic, as well as theranostic. Nanocarriers are not only able to respond to internal stimuli such as oxidative stress, weakly acidic pH, high temperature, and the high expression of particular enzymes, but also to external stimuli such as light and paramagnetic characteristics to be exploited. Results: In this work, stimulus-responsive nanocarriers functionalized with arginine-glycine-aspartic acid (Arg-Gly-Asp) sequence as well as mimetic sequences with the capability to recognize integrin receptors are analyzed. Conclusions: This review highlights the progress that has been made in the development of new nanocarriers, capable of responding to endogenous and exogenous stimuli essential to combat cancer.

Dual targeting and bioresponsive nano-PROTAC induced precise and effective lung cancer therapy

Epigenetic regulation has emerged as a promising therapeutic strategy for lung cancer treatment, which can facilitate the antitumor responses by modulating epigenetic dysregulation of target proteins in lung cancer. The proteolysis-targeting chimera (PROTAC) reagent, dBET6 shows effective inhibition of bromodomain-containing protein 4 (BRD4) that exerts antitumor efficacy by degrading BRD4 via the ubiquitin-proteasome system. Nevertheless, the low tissue specificity and bioavailability impede its therapeutic effects and clinical translation on lung cancer treatment. Herein, we developed a type of dual targeting and bioresponsive nano-PROTAC (c R GD/L LC membrane/D S-P LGA/d B ET6, named RLDPB), which was constructed by using the pH and glutathione (GSH)-responsive polymer, disulfide bond-linked poly(lactic-co-glycolic acid) (PLGA-S-S-PLGA, DS-PLGA) to load the PROTAC agent dBET6, and further camouflaged with the homotypic LLC cell membranes, followed by the conjugation with cRGD ligand to the surface of the nanoparticles. Notably, RLDPB showed enhanced celluar uptake by lung cancer cells in vitro and accumulation in the tumors via the dual targeting structure including cRGD and LLC membrane. The pH/GSH responsiveness improved the release of dBET6 from the DS-PLGA-based nanoparticles within the cells. RLDPB was demonstrated to facilitate tumor regression by inducing the apoptosis of lung cancer cells with the degradation of BRD4. Thus, RLDPB can be considered a powerful tool to suppress lung cancer, which opens a new avenue to treat lung cancer by PROTAC.

Ultrasound Guided Local Delivery of Bioorthogonal PDL1 Degrader for Enhanced Immunotherapy

Immunotherapy involving PDL1 degradation holds great potential in anti-tumor treatment. Optimal design of PDL1 degraders and subsequent efficient delivery into tumors are essential for expected efficacy, especially when abnormal tumor vasculature is considered. Herein, a nanodroplet-based novel drug delivery platform termed as NDsmTx (nanodroplet-based therapeutics) for ultrasound targeted delivery of PDL1 degrader is designed. Briefly, the shell of the NDsmTx is armed with RGD and mPD1 (a bioorthogonal PD1 mutant produced by genetic codon expansion technology can covalently bind PDL1), and the core is composed of perfluorohexane (PFH, C6F14). The RGD on the NDsmTx recognizes αvβ3 expressed by tumor vasculature, making NDsmTx accumulated in tumor practical and visible by low-frequency ultrasound (LFUS). In turn, inertial cavitation induced by LFUS facilitates mPD1 on the nanodroplet debris penetrating the tumor, where mPD1 covalently binds PDL1 and initiates a lysosomal degradation process. Through both in vitro and in vivo study, the superior performance of NDsmTx in degrading PDL1 and boosting anti-tumor immunity is confirmed. In conclusion, NDsmTx emerge as an alternative to existing PDL1 blockers in tumor immunotherapy.

Advancing Photodynamic Therapy with Nano-Conjugated Hypocrellin: Mechanisms and Clinical Applications

Hypocrellin-based photodynamic therapy (PDT) is developing as a viable cancer therapeutic option, especially when enhanced by nanoconjugation. This review investigates the methods by which nano-conjugated hypocrellin enhances therapeutic efficacy and precision when targeting cancer cells. These nanoconjugates encapsulate or covalently bind hypocrellin photosensitizers (PSs), allowing them to accumulate preferentially in malignancies. When activated by light, the nanoconjugates produce singlet oxygen and other reactive oxygen species (ROS), resulting in oxidative stress that selectively destroys cancer cells while protecting healthy tissues. We look at how they can be used to treat a variety of cancers. Clinical and preclinical studies show that they have advantages such as increased water solubility, improved tumor penetration, longer circulation times, and tailored delivery, all of which contribute to fewer off-target effects and overall toxicity. Ongoing research focuses on improving these nanoconjugates for better tumor targeting, drug release kinetics, and overcoming biological obstacles. Furthermore, the incorporation of developing technologies such as stimuli-responsive nanocarriers and combination therapies opens exciting opportunities for enhancing hypocrellin-based PDT. In conclusion, the combination of hypocrellin and nanotechnology constitutes a significant approach to cancer treatment, increasing the efficacy and safety of PDT. Future research will seek to create conjugates including hypocrellin, herceptin, and gold nanoparticles to induce apoptosis in human breast cancer cells in vitro, opening possibilities for therapeutic applications.

Photobleaching-mediated charge-convertible cyclodextrin nanoparticles achieve deep tumour penetration for rectal cancer theranostics

Although charge-converting nanoparticles (NPs) potentially penetrate tumours deeply, conventional charge conversion strategies possess limitations, including low selectivity and slow, inconsistent conversion rate within the tumour microenvironment. In this study, we synthesized a zwitterionic near-infrared cyclodextrin derivative of heptamethine cyanine and complexed it with pheophorbide-conjugated ferrocene to produce multifunctional theranostic nanotherapeutics. Our NPs demonstrated enhanced tumour-targeting ability, enabling the highly specific imaging of rectal tumours, with tumour-to-rectum signal ratios reaching up to 7.8. The zwitterionic surface charge of the NPs was rapidly converted to a cationic charge within the tumours on 880 nm near-infrared laser irradiation, promoting the tumoural penetration of NPs via transcytosis. After penetration, photodynamic/chemodynamic therapy was initiated using a 660 nm laser. Our NPs eradicated clinically relevant-sized heterotopic tumours (~250 mm3) and orthotopic rectal tumours, displaying their potential as theranostic nanoplatforms for targeting rectal cancer.

3D printing and computer-aided design techniques for drug delivery scaffolds in tissue engineering

INTRODUCTION

The challenge in tissue engineering lies in replicating the intricate structure of the native extracellular matrix. Recent advancements in AM, notably 3D printing, offer unprecedented capabilities to tailor scaffolds precisely, controlling properties like structure and bioactivity. CAD tools complement this by facilitating design using patient-specific data.

AREA’S COVERED

This review introduces additive manufacturing (AM) and computer-aided design (CAD) as pivotal tools in advancing tissue engineering, particularly cartilage regeneration. This article explores various materials utilized in AM, focusing on polymers and hydrogels for their advantageous properties in tissue engineering applications. Integrating bioactive molecules, including growth factors, into scaffolds to promote tissue regeneration is discussed alongside strategies involving different cell sources, such as stem cells, to enhance tissue development within scaffold matrices.

EXPERT OPINION

Applications of AM and CAD in addressing specific challenges like osteochondral defects and osteoarthritis in cartilage tissue engineering are highlighted. This review consolidates current research findings, offering expert insights into the evolving landscape of AM and CAD technologies in advancing tissue engineering, particularly in cartilage regeneration.

Recent advancements in nanomedicine as a revolutionary approach to treating multiple myeloma

Multiple myeloma, the second most common hematological malignancy, remains incurable with a 5-year survival rate of approximately 50 % and recurrence rates near 100 %, despite significant attempts to develop effective medicines. Therefore, there is a pressing demand in the medical field for innovative and more efficient treatments for MM. Currently, the standard approach for treating MM involves administering high-dose chemotherapy, which frequently correlates with improved results; however, one major limiting factor is the significant side effects of these medications. Furthermore, the strategies used to deliver medications to tumors limit their efficacy, whether by rapid clearance from circulation or an insufficient concentration in cancer cells. Cancer treatment has shifted from cytotoxic, nonspecific chemotherapy regimens to molecularly targeted, rationally developed drugs with improved efficacy and fewer side effects. Nanomedicines may provide an effective alternative way to avoid these limits by delivering drugs into the complicated bone marrow microenvironment and efficiently reaching myeloma cells. Putting drugs into nanoparticles can make their pharmacokinetic and pharmacodynamic profiles much better. This can increase the drug's effectiveness in tumors, extend its time in circulation in the blood, and lower its off-target toxicity. In this review, we introduce several criteria for the rational design of nanomedicine to achieve the best anti-tumoral therapeutic results. Next, we discuss recent advances in nanomedicine for MM therapy.

Drug Release via Ultrasound-Activated Nanocarriers for Cancer Treatment: A Review

Conventional cancer chemotherapy often struggles with safely and effectively delivering anticancer therapeutics to target tissues, frequently leading to dose-limiting toxicity and suboptimal therapeutic outcomes. This has created a need for novel therapies that offer greater efficacy, enhanced safety, and improved toxicological profiles. Nanocarriers are nanosized particles specifically designed to enhance the selectivity and effectiveness of chemotherapy drugs while reducing their toxicity. A subset of drug delivery systems utilizes stimuli-responsive nanocarriers, which enable on-demand drug release, prevent premature release, and offer spatial and temporal control over drug delivery. These stimuli can be internal (such as pH and enzymes) or external (such as ultrasound, magnetic fields, and light). This review focuses on the mechanics of ultrasound-induced drug delivery and the various nanocarriers used in conjunction with ultrasound. It will also provide a comprehensive overview of key aspects related to ultrasound-induced drug delivery, including ultrasound parameters and the biological effects of ultrasound waves.

Nanomaterial-Enhanced Microneedles: Emerging Therapies for Diabetes and Obesity

Drug delivery systems (DDS) have improved therapeutic agent administration by enhancing efficacy and patient compliance while minimizing side effects. They enable targeted delivery, controlled release, and improved bioavailability. Transdermal drug delivery systems (TDDS) offer non-invasive medication administration and have evolved to include methods such as chemical enhancers, iontophoresis, microneedles (MN), and nanocarriers. MN technology provides innovative solutions for chronic metabolic diseases like diabetes and obesity using various MN types. For diabetes management, MNs enable continuous glucose monitoring, diabetic wound healing, and painless insulin delivery. For obesity treatment, MNs provide sustained transdermal delivery of anti-obesity drugs or nanoparticles (NPs). Hybrid systems integrating wearable sensors and smart materials enhance treatment effectiveness and patient management. Nanotechnology has advanced drug delivery by integrating nano-scaled materials like liposomes and polymeric NPs with MNs. In diabetes management, glucose-responsive NPs facilitate smart insulin delivery. At the same time, lipid nanocarriers in dissolving MNs enable extended release for obesity treatment, enhancing drug stability and absorption for improved metabolic disorder therapies. DDS for obesity and diabetes are advancing toward personalized treatments using smart MN enhanced with nanomaterials. These innovative approaches can enhance patient outcomes through precise drug administration and real-time monitoring. However, widespread implementation faces challenges in ensuring biocompatibility, improving technologies, scaling production, and obtaining regulatory approval. This review will present recent advances in developing and applying nanomaterial-enhanced MNs for diabetes and obesity management while also discussing the challenges, limitations, and future perspectives of these innovative DDS.

Stimuli-Responsive Polymeric Nanocarriers Accelerate On-Demand Drug Release to Combat Glioblastoma

Glioblastoma multiforme (GBM) is a highly malignant brain tumor with a poor prognosis and limited treatment options. Drug delivery by stimuli-responsive nanocarriers holds great promise for improving the treatment modalities of GBM. At the beginning of the review, we highlighted the stimuli-active polymeric nanocarriers carrying therapies that potentially boost anti-GBM responses by employing endogenous (pH, redox, hypoxia, enzyme) or exogenous stimuli (light, ultrasonic, magnetic, temperature, radiation) as triggers for controlled drug release mainly via hydrophobic/hydrophilic transition, degradability, ionizability, etc. Modifying these nanocarriers with target ligands further enhanced their capacity to traverse the blood-brain barrier (BBB) and preferentially accumulate in glioma cells. These unique features potentially lead to more effective brain cancer treatment with minimal adverse reactions and superior therapeutic outcomes. Finally, the review summarizes the existing difficulties and future prospects in stimuli-responsive nanocarriers for treating GBM. Overall, this review offers theoretical guidelines for developing intelligent and versatile stimuli-responsive nanocarriers to facilitate precise drug delivery and treatment of GBM in clinical settings.

Corked Microcapsules Enabling Controlled Ultrasound-Mediated Protein Delivery

While ultrasound represents a facile, portable, and noninvasive trigger for drug delivery vehicles, most reported ultrasound-triggered drug delivery vehicles predominately present "burst" release profiles that are hard to control after the initial activation stimulus. Herein, we report a submerged electrospraying technique to fabricate protein-loaded microcapsules in which silica "corks" are embedded within the microcapsule shell. Upon the application of an ultrasound trigger, the corks can be perturbed within the shell, allowing for the release of the protein payload through a phantom tissue mimic to a degree proportional to the number/time of pulses applied. Specifically, multiple ultrasound pulses were shown to enable a 15- to 23-fold increase in the rate of release of the model bovine serum albumin protein payload relative to no ultrasound being applied, with release returning to a lower level when the ultrasound stimulus was removed. Coupled with the low cytotoxicity of the vehicle components, the corked microcapsules show promise for expanding the potential to use ultrasound to facilitate both on-demand and pulsatile release profiles.

Synergistic Potential of Nanomedicine in Prostate Cancer Immunotherapy: Breakthroughs and Prospects

Given the global prevalence of prostate cancer in men, it is crucial to explore more effective treatment strategies. Recently, immunotherapy has emerged as a promising cancer treatment due to its unique mechanism of action and potential long-term effectiveness. However, its limited efficacy in prostate cancer has prompted renewed interest in developing strategies to improve immunotherapy outcomes. Nanomedicine offers a novel perspective on cancer treatment with its unique size effects and surface properties. By employing targeted delivery, controlled release, and enhanced immunogenicity, nanoparticles can be synergized with nanomedicine platforms to amplify the effectiveness of immunotherapy in treating prostate cancer. Simultaneously, nanotechnology can address the limitations of immunotherapy and the challenges of immune escape and tumor microenvironment regulation. Additionally, the synergistic effects of combining nanomedicine with other therapies offer promising clinical outcomes. Innovative applications of nanomedicine include smart nanocarriers, stimulus-responsive systems, and precision medicine approaches to overcome translational obstacles in prostate cancer immunotherapy. This review highlights the transformative potential of nanomedicine in enhancing prostate cancer immunotherapy and emphasizes the need for interdisciplinary collaboration to drive research and clinical applications forward.

Liposomal delivery of organoselenium-cisplatin complex as a novel therapeutic approach for colon cancer therapy

Cisplatin is a widely-used chemotherapeutic agent for the treatment of various solid neoplasms including colon cancer. Cisplatin-induced DNA damage is restricted due to dose-related adverse reactions as well as primary resistance mechanisms. Therefore, it is imperative to utilize novel therapeutic approaches to circumvent cisplatin limitations and attenuate its normal tissues toxicity. In this study, we exploited a novel PEGylated liposomes with greater efficiency to treat colon cancer. For this, an organoselenium compound (diselanediylbis decanoic acid (DDA)) was synthesized, and liposomes composed of Egg PC or HSPC, as well as DOPE, mPEG2000-DSPE, cholesterol and DDA at varying molar ratios were prepared by using thin-film method. Cisplatin loading was performed through incubation with liposomes. Characterization of nanoliposomes indicated a favarable size range of 91-122 nm and negative zeta potential of -9 to -22 mv. The organoselenium compound significantly improved cisplatin loading efficiency within the liposomes (83.4 %). Results also revealed an efficient bioactivity of cisplatin liposome on C26 cells compared to the normal cells. Further, DDA bearing liposomes significantly improved drug residence time in circulation, reduced toxicity associated with the normal tissues, and enhanced drug accumulation within the oxidative tumor microenvironment. Collectively, results indicated that cisplatin encasement within liposomes by using this method could significantly improve the therapeutic efficacy in vivo, and merits further investigations.

Nanozymes-Mediated Cascade Reaction System for Tumor-Specific Diagnosis and Targeted Therapy

Cascade reactions are described as efficient and versatile tools, and organized catalytic cascades can significantly improve the efficiency of chemical interworking between nanozymes. They have attracted great interest in many fields such as chromogenic detection, biosensing, tumor diagnosis, and therapy. However, how to selectively kill tumor cells by enzymatic reactions without harming normal cells, as well as exploring two or more enzyme-engineered nanoreactors for cascading catalytic reactions, remain great challenges in the field of targeted and specific cancer diagnostics and therapy. The latest research advances in nanozyme-catalyzed cascade processes for cancer diagnosis and therapy are described in this article. Here, various sensing strategies are summarized, for tumor-specific diagnostics. Targeting mechanisms for tumor treatment using cascade nanozymes are classified and analyzed, "elements" and "dimensions" of cascade nanozymes, types, designs of structure, and assembly modes of highly active and specific cascade nanozymes, as well as a variety of new strategies of tumor targeting based on the cascade reaction of nanozymes. Finally, the integrated application of the cascade nanozymes systems in tumor-targeted and specific diagnostic therapy is summarized, which will lay the foundation for the design of more rational, efficient, and specific tumor diagnostic and therapeutic modalities in the future.

Therapeutic delivery of siRNA for the management of breast cancer and triple-negative breast cancer

Breast cancer is the leading cause of cancer-related deaths among women globally. The difficulties with anticancer medications, such as ineffective targeting, larger doses, toxicity to healthy cells and side effects, have prompted attention to alternate approaches to address these difficulties. RNA interference by small interfering RNA (siRNA) is one such tactic. When compared with chemotherapy, siRNA has several advantages, including the ability to quickly modify and suppress the expression of the target gene and display superior efficacy and safety. However, there are known challenges and hurdles that limits their clinical translation. Decomposition by endonucleases, renal clearance, hydrophilicity, negative surface charge, short half-life and off-target effects of naked siRNA are obstacles that hinder the desired biological activity of naked siRNA. Nanoparticulate systems such as polymeric, lipid, lipid-polymeric, metallic, mesoporous silica nanoparticles and several other nanocarriers were used for effective delivery of siRNA and to knock down genes involved in breast cancer and triple-negative breast cancer. The focus of this review is to provide a comprehensive picture of various strategies utilized for delivering siRNA, such as combinatorial delivery, development of modified nanoparticles, smart nanocarriers and nanocarriers that target angiogenesis, cancer stem cells and metastasis of breast cancer.

Nanotechnology in Advancing Chimeric Antigen Receptor T Cell Therapy for Cancer Treatment

Chimeric antigen receptor (CAR) T cell therapy has emerged as a groundbreaking treatment for hematological cancers, yet it faces significant hurdles, particularly regarding its efficacy in solid tumors and concerning associated adverse effects. This review provides a comprehensive analysis of the advancements and ongoing challenges in CAR-T therapy. We highlight the transformative potential of nanotechnology in enhancing CAR-T therapy by improving targeting precision, modulating the immune-suppressive tumor microenvironment, and overcoming physical barriers. Nanotechnology facilitates efficient CAR gene delivery into T cells, boosting transfection efficiency and potentially reducing therapy costs. Moreover, nanotechnology offers innovative solutions to mitigate cytokine release syndrome (CRS) and immune effector cell-associated neurotoxicity syndrome (ICANS). Cutting-edge nanotechnology platforms for real-time monitoring of CAR-T cell activity and cytokine release are also discussed. By integrating these advancements, we aim to provide valuable insights and pave the way for the next generation of CAR-T cell therapies to overcome current limitations and enhance therapeutic outcomes.

Metal-organic frameworks in drug delivery: engineering versatile platforms for therapeutic applications

Recently, metal-organic frameworks (MOFs) have attracted much attention as versatile materials for drug delivery and personalized medicine. MOFs are porous structures made up of metal ions coupled with organic ligands. This review highlights the synthesis techniques used to design MOFs with specific features such as surface area and pore size, and the drug encapsulation within MOFs not only improves their stability and solubility but also allows for controlled release kinetics, which improves therapeutic efficacy and minimizes adverse effects. Furthermore, it discusses the challenges and potential advantages of MOF-based drug delivery, such as MOF stability, biocompatibility, and scale-up production. With further advancements in MOF synthesis, functionalization techniques, and understanding of their interactions using biological systems, MOFs can have significant promise for expanding the area of personalized medicine and improving patient outcomes.

Nanomedicine for combination of chemodynamic therapy and immunotherapy of cancers

Chemodynamic therapy (CDT), as a new type of therapy, has received more and more attention in the field of tumor therapy in recent years. By virtue of the characteristics of weak acidity and excess H2O2 in the tumor microenvironment, CDT uses the Fenton or Fenton-like reactions to catalyze the transformation of H2O2 into strongly oxidizing ˙OH, resulting in increased intracellular oxidative stress for lipid oxidation, protein inactivation, or DNA damage, and finally inducing apoptosis of cancer cells. In particular, CDT has the advantage of tumor specificity. However, the therapeutic efficacy of CDT frequently depends on the catalytic efficiency of the Fenton reaction, which needs the presence of sufficient H2O2 and catalytic metal ions. Relatively low concentrations of H2O2 and the lack of catalytic metal ions usually limit the final therapeutic effect. The combination of CDT with immunotherapy will be an effective means to improve the therapeutic effect. In this review paper, the recent progress related to nanomedicine for the combination of CDT and immunotherapy is summarized. Immunogenic death of tumor cells, immune checkpoint inhibitors, and stimulator of interferon gene (STING) activation as the main immunotherapy strategies to combine with CDT are discussed. Finally, the challenges and prospects for the clinical translation and future development direction are discussed.

Acidic Lysosome-Anchoring Croconium-Based Nanoplatform for Enhanced Triple-Mode Bioimaging and Fe3+-Triggered Tumor Synergistic Therapy

Metal-modulated croconium dyes with multimodal-imaging and synergistic therapy in the tumor microenvironment have exhibited great potential in tumor theranostics. However, their unideal structure optimization always weakened the efficacy of near-infrared fluorescence-photoacoustic (NIRF/PA) imaging and photothermal therapy (PTT). Here, we screened croconium dye containing two indole groups with better NIRF/PA imaging and PTT in their family, linked to two morpholine rings, and obtained CR-736, as a lysosome-targeting and Fe3+-modulated agent. The established CR-736-Fe3+ nanoplatform was accurately delivered to the breast tumor site, released CR-736 and Fe3+ in the lower acidic lysosome microenvironment, and activated pH-responsive NIRF/PA/magnetic resonance imaging and PTT. Furthermore, ferroptosis generated hydroxyl free radicals and lipid peroxide by consuming GSH and H2O2 by dint of the accumulation of Fe3+ in tumor cells, which resulted in the inhibition of the expression of heat shock proteins and the concomitant recovery of PTT. The synergistic therapy of PTT, ferroptosis, and chemodynamics was further optimized to the maximal extent in tumor lysosome acidic microenvironment and proved both in vitro and a mouse tumor model. This study opens a new avenue in designing excellent and unique croconium-based nanoplatforms, synergizing multiple tumor theranostic methods, and further optimizing the theranostic effects in tumor microenvironment.

Microenvironment-responsive nanosystems for ischemic stroke therapy

Ischemic stroke, a common neurological disorder caused by impaired blood supply to the brain, presents a therapeutic challenge. Conventional treatments like thrombolysis and neuroprotection drugs lack ideal drug delivery systems, limiting their effectiveness. Selectively delivering therapies to the ischemic cerebral tissue holds great potential for preventing and/or treating ischemia-related pathological symptoms. The unique pathological microenvironment of the brain after ischemic stroke, characterized by hypoxia, acidity, and inflammation, offers new possibilities for targeted drug delivery. Pathological microenvironment-responsive nanosystems, extensively investigated in tumors with hypoxia-responsive systems as an example, could also respond to the ischemic cerebral microenvironment and achieve brain-targeted drug delivery and release. These emerging nanosystems are gaining traction for ischemic stroke treatment. In this review, we expound on the cerebral pathological microenvironment and clinical treatment strategies of ischemic stroke, highlight various stimulus-responsive materials employed in constructing ischemic stroke microenvironment-responsive nano delivery systems, and discuss the application of these microenvironment-responsive nanosystems in microenvironment regulation for ischemic stroke treatment.

Green synthesis of anti-cancer drug-loaded gold nanoparticles for low-intensity pulsed ultrasound targeted drug release

In the present work, we have designed a one-pot green protocol in which anti-cancer drugs (curcumin and doxorubicin) can be directly loaded on the surface of gold nanoparticles during their formation. We have further demonstrated that low-intensity pulsed ultrasound (LIPUS) can be used to effectively induce the release of anti-cancer drugs from the surface of gold nanoparticles in an ex vivo tissue model. With this protocol, gold nanoparticles can be easily loaded with different types of anticancer drugs, irrespective of their affinity towards water, and even hydrophobic molecules, like curcumin, can be attached onto the gold nanoparticles in an aqueous medium. The method is very simple and straightforward and does not require stirring or mechanical shaking. The drug molecules interact with the gold seeds formed during the reduction and growth process and modulate the final morphology into a spherical shape. A black-colored colloidal solution of gold nanowire networks is formed in the absence of these anti-cancer drug molecules in the reaction mixture. We used hyperspectral-enhanced dark field microscopy to examine the uptake of gold nanoparticles by breast cancer cells. Upon exposure to LIPUS, the release of the anti-cancer drug from the particle surface can be quantified by fluorescence measurements. This release of drug molecules along with trisodium citrate from the surface of gold nanoparticles by ultrasound resulted in their destabilization and subsequent aggregation, which could be visually observed through the change in the color of colloidal sol. Cancer cell viability was studied by MTT assay to examine the efficacy of this nanoparticle-based drug delivery system. Ultraviolet-visible spectroscopy, dynamic light scattering (DLS), and transmission electron microscope (TEM) analysis were used to characterize the nanoparticles and quantify anti-cancer drug release.

Stimuli-Responsive Silica Silanol Conjugates: Strategic Nanoarchitectonics in Targeted Drug Delivery

The design of novel drug delivery systems is exceptionally critical in disease treatments. Among the existing drug delivery systems, mesoporous silica nanoparticles (MSNs) have shown profuse promise owing to their structural stability, tunable morphologies/sizes, and ability to load different payload chemistry. Significantly, the presence of surface silanol groups enables functionalization with relevant drugs, imaging, and targeting agents, promoting their utility and popularity among researchers. Stimuli-responsive silanol conjugates have been developed as a novel, more effective way to conjugate, deliver, and release therapeutic drugs on demand and precisely to the selected location. Therefore, it is urgent to summarize the current understanding and the surface silanols' role in making MSN a versatile drug delivery platform. This review provides an analytical understanding of the surface silanols, chemistry, identification methods, and their property-performance correlation. The chemistry involved in converting surface silanols to a stimuli-responsive silica delivery system by endogenous/exogenous stimuli, including pH, redox potential, temperature, and hypoxia, is discussed in depth. Different chemistries for converting surface silanols to stimuli-responsive bonds are discussed in the context of drug delivery. The critical discussion is culminated by outlining the challenges in identifying silanols' role and overcoming the limitations in synthesizing stimuli-responsive mesoporous silica-based drug delivery systems.

Designing intelligent bioorthogonal nanozymes: Recent advances of stimuli-responsive catalytic systems for biomedical applications

Bioorthogonal nanozymes have emerged as a potent tool in biomedicine due to their unique ability to perform enzymatic reactions that do not interfere with native biochemical processes. The integration of stimuli-responsive mechanisms into these nanozymes has further expanded their potential, allowing for controlled activation and targeted delivery. As such, intelligent bioorthogonal nanozymes have received more and more attention in developing therapeutic approaches. This review provides a comprehensive overview of the recent advances in the development and application of stimuli-responsive bioorthogonal nanozymes. By summarizing the design outlines for anchoring bioorthogonal nanozymes with stimuli-responsive capability, this review seeks to offer valuable insights and guidance for the rational design of these remarkable materials. This review highlights the significant progress made in this exciting field with different types of stimuli and the various applications. Additionally, it also examines the current challenges and limitations in the design, synthesis, and application of these systems, and proposes potential solutions and research directions. This review aims to stimulate further research toward the development of more efficient and versatile stimuli-responsive bioorthogonal nanozymes for biomedical applications.

Stimuli-Responsive Aptamer-Drug Conjugates for Targeted Drug Delivery and Controlled Drug Release

Chemotherapy is widely used for cancer therapy but with unsatisfied efficacy, mainly due to the inefficient delivery of anticancer agents. Among the critical "five steps" drug delivery process, internalization into tumor cells and intracellular drug release are two important steps for the overall therapeutic efficiency. Strategy based on active targeting or TME-responsive is developed individually to improve therapeutic efficiency, but with limited improvement. However, the combination of these two strategies could potentially augment the drug delivery efficiency and therapeutic efficiency, consequently. Therefore, this work constructs a library of stimuli-responsive aptamer-drug conjugates (srApDCs), as "dual-targeted" strategy for cancer treatment that enables targeted drug delivery and controlled drug release. Specifically, this work uses different stimuli-responsive linkers to conjugate a tumor-targeting aptamer (i.e., AS1411) with drugs, forming the library of srApDCs for targeted cancer treatment. This design hypothesis is validated by the experimental data, which indicated that the aptamer could selectively enhance uptake of the srApDCs and the linkers could be cleaved by pathological cues in the TME to release the drug payload, leading to a significant enhancement of therapeutic efficacy. These results underscore the potential of the approach, providing a promising methodology for cancer therapy.

Nanomedicine-induced programmed cell death in cancer therapy: mechanisms and perspectives

The balance of programmed cell death (PCD) mechanisms, including apoptosis, autophagy, necroptosis and others, is pivotal in cancer progression and treatment. Dysregulation of these pathways results in uncontrolled cell growth and resistance to conventional therapies. Nanomedicine offers a promising solution in oncology through targeted drug delivery enabling precise targeting of cancer cells while preserving healthy tissues. This approach reduces the side effects of traditional chemotherapy and enhances treatment efficacy by engaging PCD pathways. We details each PCD pathway, their mechanisms, and innovative nanomedicine strategies to activate these pathways, thereby enhancing therapeutic specificity and minimizing harm to healthy tissues. The precision of nanotechnology in targeting PCD pathways promises significant improvements in cancer treatment outcomes. This synergy between nanotechnology and targeted PCD activation could lead to more effective and less toxic cancer therapies, heralding a new era in cancer treatment.

Theoretical basis, state and challenges of living cell-based drug delivery systems

The therapeutic efficacy of drugs is determined, to a certain extent, by the efficiency of drug delivery. The low efficiency of drug delivery systems (DDSs) is frequently associated with serious toxic side effects and can even prove fatal in certain cases. With the rapid development of technology, drug delivery has evolved from using traditional frameworks to using nano DDSs (NDDSs), endogenous biomaterials DDSs (EBDDSs), and living cell DDSs (LCDDSs). LCDDSs are receiving widespread attention from researchers at present owing to the unique advantages of living cells in targeted drug delivery, including their excellent biocompatibility properties, low immunogenicity, unique biological properties and functions, and role in the treatment of diseases. However, the theoretical basis and techniques involved in the application of LCDDSs have not been extensively summarized to date. Therefore, this review comprehensively summarizes the properties and applications of living cells, elaborates the various drug loading approaches and controlled drug release, and discusses the results of clinical trials. The review also discusses the current shortcomings and prospects for the future development of LCDDSs, which will serve as highly valuable insights for the development and clinical transformation of LCDDSs in the future.

Stimuli-Responsive Polymersomes: Reshaping the Immunosuppressive Tumor Microenvironment

The progression of cancer involves mutations in normal cells, leading to uncontrolled division and tissue destruction, highlighting the complexity of tumor microenvironments (TMEs). Immunotherapy has emerged as a transformative approach, yet the balance between efficacy and safety remains a challenge. Nanoparticles such as polymersomes offer the possibility to precisely target tumors, deliver drugs in a controlled way, effectively modulate the antitumor immunity, and notably reduce side effects. Herein, stimuli-responsive polymersomes, with capabilities for carrying multiple therapeutics, are highlighted for their potential in enhancing antitumor immunity through mechanisms like inducing immunogenic cell death and activating STING (stimulator of interferon genes), etc. The recent progress of utilizing stimuli-responsive polymersomes to reshape the TME is reviewed here. The advantages and limitations to applied stimuli-responsive polymersomes are outlined. Additionally, challenges and future prospects in leveraging polymersomes for cancer therapy are discussed, emphasizing the need for future research and clinical translation.

Brain gliomas: Diagnostic and therapeutic issues and the prospects of drug-targeted nano-delivery technology

Glioma is the most common intracranial malignant tumor, with severe difficulty in treatment and a low patient survival rate. Due to the heterogeneity and invasiveness of tumors, lack of personalized clinical treatment design, and physiological barriers, it is often difficult to accurately distinguish gliomas, which dramatically affects the subsequent diagnosis, imaging treatment, and prognosis. Fortunately, nano-delivery systems have demonstrated unprecedented capabilities in diagnosing and treating gliomas in recent years. They have been modified and surface modified to efficiently traverse BBB/BBTB, target lesion sites, and intelligently release therapeutic or contrast agents, thereby achieving precise imaging and treatment. In this review, we focus on nano-delivery systems. Firstly, we provide an overview of the standard and emerging diagnostic and treatment technologies for glioma in clinical practice. After induction and analysis, we focus on summarizing the delivery methods of drug delivery systems, the design of nanoparticles, and their new advances in glioma imaging and treatment in recent years. Finally, we discussed the prospects and potential challenges of drug-delivery systems in diagnosing and treating glioma.

M1 Macrophage-Targeted Curcumin Nanocrystals with l-Arginine-Modified for Acute Lung Injury by Inhalation

Acute Lung Injury/Acute Respiratory Distress Syndrome (ALI/ARDS) with clinical manifestations of respiratory distress and hypoxemia remains a significant cause of respiratory failure, boasting a persistently high incidence and mortality rate. Given the central role of M1 macrophages in the pathogenesis of acute lung injury (ALI), this study utilized the anti-inflammatory agent curcumin as a model drug. l-arginine (L-Arg) was employed as a targeting ligand, and chitosan was initially modified with l-arginine. Subsequently, it was utilized as a surface modifier to prepare inhalable nano-crystals loaded with curcumin (Arg-CS-Cur), aiming for specific targeting of pulmonary M1 macrophages. Compared with unmodified chitosan-curcumin nanocrystals (CS-Cur), Arg-CS-Cur exhibited higher uptake in vitro by M1 macrophages, as evidenced by flow cytometry showing the highest fluorescence intensity in the Arg-CS-Cur group (P < 0.01). In vivo accumulation was greater in inflamed lung tissues, as indicated by small animal imaging demonstrating higher lung fluorescence intensity in the DiR-Arg-CS-Cur group compared to the DiR-CS-Cur group in the rat ALI model (P < 0.05), peaking at 12 h. Moreover, Arg-CS-Cur demonstrated enhanced therapeutic effects in both LPS-induced RAW264.7 cells and ALI rat models. Specifically, treatment with Arg-CS-Cur significantly suppressed NO release and levels of TNF-α and IL-6 in RAW264.7 cells (p < 0.01), while in ALI rat models, expression levels of TNF-α and IL-6 in lung tissues were significantly lower than those in the model group (P < 0.01). Furthermore, lung tissue damage was significantly reduced, with histological scores significantly lower than those in the CS-Cur group (P < 0.01). In conclusion, these findings underscore the targeting potential of l-arginine-modified nanocrystals, which effectively enhance curcumin concentration in inflammatory environments by selectively targeting M1 macrophages. This study thus introduces novel perspectives and theoretical support for the development of targeted therapeutic interventions for acute inflammatory lung diseases, including ALI/ARDS.