Gas therapy potentiates aggregation-induced emission luminogen-based photoimmunotherapy of poorly immunogenic tumors through cGAS-STING pathway activation

Integration of STING activation and COX-2 inhibition via steric-hindrance effect tuned nanoreactors for cancer chemoimmunotherapy

Integrating immunotherapy with nanomaterials-based chemotherapy presents a promising avenue for amplifying antitumor outcomes. Nevertheless, the suppressive tumor immune microenvironment (TIME) and the upregulation of cyclooxygenase-2 (COX-2) induced by chemotherapy can hinder the efficacy of the chemoimmunotherapy. This study presents a TIME-reshaping strategy by developing a steric-hindrance effect tuned zinc-based metal-organic framework (MOF), designated as CZFNPs. This nanoreactor is engineered by in situ loading of the COX-2 inhibitor, C-phycocyanin (CPC), into the framework building blocks, while simultaneously weakening the stability of the MOF. Consequently, CZFNPs achieve rapid pH-responsive release of zinc ions (Zn2+) and CPC upon specific transport to tumor cells overexpressing folate receptors. Accordingly, Zn2+ can induce reactive oxygen species (ROS)-mediated cytotoxicity therapy while synchronize with mitochondrial DNA (mtDNA) release, which stimulates mtDNA/cGAS-STING pathway-mediated innate immunity. The CPC suppresses the chemotherapy-induced overexpression of COX-2, thus cooperatively reprogramming the suppressive TIME and boosting the antitumor immune response. In xenograft tumor models, the CZFNPs system effectively modulates STING and COX-2 expression, converting "cold" tumors into "hot" tumors, thereby resulting in ≈ 4-fold tumor regression relative to ZIF-8 treatment alone. This approach offers a potent strategy for enhancing the efficacy of combined nanomaterial-based chemotherapy and immunotherapy.

Analysis of optical properties and response mechanism of H2S fluorescent probe based on rhodamine derivatives

H2S plays a crucial role in numerous physiological and pathological processes. In this project, a new fluorescent probe, SG-H2S, for the detection of H2S, was developed by introducing the recognition group 2,4-dinitrophenyl ether. The combination of rhodamine derivatives can produce both colorimetric reactions and fluorescence reactions. Compared with the current H2S probes, the main advantages of SG-H2S are its wide pH range (5-9), fast response (30 min), and high selectivity in competitive species (including biological mercaptan). The probe SG-H2S has low cytotoxicity and has been successfully applied to imaging in MCF-7 cells, HeLa cells, and BALB/c nude mice. We hope that SG-H2S will provide a vital method for the field of biology.

Bionic aggregation-induced emission photosensitizer for enhanced cancer immunotherapy

Cold exposure therapy (CE), as an inexpensive method, has shown great potential in cancer therapy. Exploring the combined anti-tumor mechanism of CE and traditional therapies (such as photodynamic therapy (PDT)) is exciting and promising. Here, a bionic aggregation-induced emission photosensitizer system (named THL) is designed for combined CE to enhance anti-tumor immunotherapy. THL inherits the homologous targeting ability of tumor derived exosomes, promoting the enrichment of THL at the tumor site. Under external illumination, THL generates hydroxyl radicals and superoxide anions through type I PDT. In addition, mice are pretreated with cold exposure, which promotes THL mediated PDT and reactive oxygen species (ROS) generation by reducing the production of ATP and GSH in tumor tissue. This combination therapy increases production of ROS within the tumor, inhibits the growth of distant tumors, recurrent and rechallenged tumors and increases the number of cytotoxic CD8+T cells and memory T cells. Compared to PDT alone, combination therapy shows greater advantages in tumor immunotherapy. The combination therapy strategy provides new ideas for cancer immunotherapy.

Phototherapeutic applications of benzophenone-containing NIR-emitting photosensitizers based on different receptor modulations

Photodynamic therapy (PDT) plays a crucial role in treating cancer and major infectious diseases. However, the hypoxic microenvironment and deep-seated tumors often compromise the effectiveness of photosensitizers (PSs). PSs primarily generate type-II reactive oxygen species (ROS), which are limited under hypoxic conditions. Pyridinium salts frequently exhibit critical dark toxicity in vitro. Moreover, PDT alone often fails to achieve optimal anti-tumor effects compared to its combined application with photothermal therapy (PTT). To address these issues, we replaced pyridinium with quinolinium, significantly reducing dark toxicity. Additionally, the incorporation of benzophenone enhanced ROS generation, achieving a synergistic effect of type-I and type-II PDT. Fine-tuning the conjugated structure enhanced the donor-acceptor (D-A) intensity, while the stretching vibrations of carbon-carbon double bonds and carbon-nitrogen triple bonds red-shifted the excitation wavelength to the near-infrared (NIR) region and improved the photothermal conversion efficiency (PCE). This strategy provides a molecular design approach for achieving synergy between PDT and PTT. The synthesized four NIR-emitting aggregation-induced emission quinolinium salts exhibited mitochondrial targeting ability and low dark toxicity. Among them, FCN-TPAQ-BP showed excellent ROS generation capability, a PCE of 39.2%, good biocompatibility, and low dark toxicity, making it an ideal candidate for enhancing PDT's antitumor efficacy.

Metal ion interference therapy: metal-based nanomaterial-mediated mechanisms and strategies to boost intracellular "ion overload" for cancer treatment

Metal ion interference therapy (MIIT) has emerged as a promising approach in the field of nanomedicine for combatting cancer. With advancements in nanotechnology and tumor targeting-related strategies, sophisticated nanoplatforms have emerged to facilitate efficient MIIT in xenografted mouse models. However, the diverse range of metal ions and the intricacies of cellular metabolism have presented challenges in fully understanding this therapeutic approach, thereby impeding its progress. Thus, to address these issues, various amplification strategies focusing on ionic homeostasis and cancer cell metabolism have been devised to enhance MIIT efficacy. In this review, the remarkable progress in Fe, Cu, Ca, and Zn ion interference nanomedicines and understanding their intrinsic mechanism is summarized with particular emphasis on the types of amplification strategies employed to strengthen MIIT. The aim is to inspire an in-depth understanding of MIIT and provide guidance and ideas for the construction of more powerful nanoplatforms. Finally, the related challenges and prospects of this emerging treatment are discussed to pave the way for the next generation of cancer treatments and achieve the desired efficacy in patients.

C-di-GMP@ZIF-8 nanocomposite injectable hydrogel based on modified chitosan and hyaluronic acid for infected wound healing by activating STING signaling

The treatment of infected wounds relies on antibiotics; however, increasing drug resistance has made therapeutic processes more difficult. Activating self-innate immune abilities may provide a promising alternative to treat wounds with bacterial infections. In this work, we constructed an immunogenic injectable hydrogel crosslinked by the Schiff base reaction of carboxymethyl chitosan (NOCC) and aldehyde hyaluronic acid (AHA) and encapsulated with stimulator of interferon genes (STING) agonist c-di-GMP loaded ZIF-8 nanoparticles (c-di-GMP@ZIF-8). Nanocubic ZIF-8 was screened as the most efficient intracellular drug delivery vector from five differently-shaped morphologies. The NOCC/AHA hydrogel released c-di-GMP@ZIF-8 more quickly (43 %) in acidic environment (pH = 5.5) of infected wounds compared with 34 % in non-infected wound environment (pH = 7.4) at 96 h due to pH-responsive degradation performance. The released c-di-GMP@ZIF-8 was found to activate the STING signaling of macrophages and enhance the secretion of IFN-β, CCL2, and CXCL12 5.8-7.6 times compared with phosphate buffer saline control, which effectively inhibited S. aureus growth and promoted fibroblast migration. In rat models with infected wounds, the c-di-GMP@ZIF-8 nanocomposite hydrogels improved infected wound healing by promoting granulation tissue regeneration, alleviating S. aureus-induced inflammation, and improving angiogenesis. Altogether, this study demonstrated a feasible strategy using STING-targeted and pH-responsive hydrogels for infected wound management.

Tumor microenvironment-responsive manganese-based nano-modulator activate the cGAS-STING pathway to enhance innate immune system response

BACKGROUND

Manganese ions (Mn2+) combined with adjuvants capable of damaging and lysing tumor cells form an antitumor nano-modulator that enhances the immune efficacy of cancer therapy through the cascade activation of the cyclic GMP-AMP interferon gene synthase-stimulator (cGAS-STING) pathway, which underscores the importance of developing antitumor nano-modulators, which induce DNA damage and augment cGAS-STING activity, as a critical future research direction. METHODS AND RESULTS: We have successfully synthesized an antitumor nano-modulator, which exhibits good dispersibility and biosafety. This nano-modulator is engineered by loading manganese dioxide nanosheets (M-NS) with zebularine (Zeb), known for its immunogenicity-enhancing effects, and conducting targeted surface modification using hyaluronic acid (HA). After systemic circulation to the tumor site, Mn2+, Zeb, and reactive oxygen species (ROS) are catalytically released in the tumor microenvironment by H+ and H2O2. These components can directly or indirectly damage the DNA or mitochondria of tumor cells, thereby inducing programmed cell death. Furthermore, they promote the accumulation of double-stranded DNA (dsDNA) in the cytoplasm, enhancing the activation of the cGAS-STING signalling pathway and boosting the production of type I interferon and the secretion of pro-inflammatory cytokines. Additionally, Zeb@MH-NS enhances the maturation of dendritic cells, the infiltration of cytotoxic T lymphocytes, and the recruitment of natural killer cells at the tumor site.

CONCLUSIONS

This HA-modified manganese-based hybrid nano-regulator can enhance antitumor therapy by boosting innate immune activity and may provide new directions for immunotherapy and clinical translation in cancer.

Stimuli-responsive nanotheranostic systems conjugated with AIEgens for advanced cancer bio-imaging and treatment

Aggregation-induced emission (AIE) is a unique phenomenon observed in various materials such as organic luminophores, carbon dots (CDs), organic-inorganic nanocomposites, fluorescent dye molecules, and nanoparticles (NPs). These AIE-active materials, or AIEgens, are ideal for balancing multifunctional phototheranostics and energy dissipation. AIE properties can manifest in organic fluorescent probes, rendering them effective for cancer treatment due to their ability to penetrate deeply and provide high therapeutic efficacy. This efficacy is attributed to their high photobleaching thresholds, ability to induce Stokes shifts, and capacity to activate fluorophores. Therefore, the development of innovative AIE-based materials for disease diagnosis and treatment, particularly for cancer, is both important and promising. Recent years have seen successful demonstrations of nanoparticles with AIE properties being used for photodynamic therapy (PDT) and multimodal imaging of tumor cells. These fluorophores have been shown to impact mitochondria and lysosomes, generate reactive oxygen species (ROS), activate the immune system, load and release drugs, and ultimately induce apoptosis in tumor cells. In this review, we examine previous studies on the manufacturing methods and effects of AIEgens on cancer cells, with a theranostic strategy of simultaneous treatment and imaging. We also investigate the factors affecting drug delivery on different cancer cells, including internal stimuli such as pH, ROS, enzymes, and external stimuli like near-infrared (NIR) light and ultrasound waves.

Cytosolic DNA initiates a vicious circle of aging-related endothelial inflammation and mitochondrial dysfunction via STING: the inhibitory effect of Cilostazol

Endothelial senescence, aging-related inflammation, and mitochondrial dysfunction are prominent features of vascular aging and contribute to the development of aging-associated vascular disease. Accumulating evidence indicates that DNA damage occurs in aging vascular cells, especially in endothelial cells (ECs). However, the mechanism of EC senescence has not been completely elucidated, and so far, there is no specific drug in the clinic to treat EC senescence and vascular aging. Here we show that various aging stimuli induce nuclear DNA and mitochondrial damage in ECs, thus facilitating the release of cytoplasmic free DNA (cfDNA), which activates the DNA-sensing adapter protein STING. STING activation led to a senescence-associated secretory phenotype (SASP), thereby releasing pro-aging cytokines and cfDNA to further exacerbate mitochondrial damage and EC senescence, thus forming a vicious circle, all of which can be suppressed by STING knockdown or inhibition. Using next-generation RNA sequencing, we demonstrate that STING activation stimulates, whereas STING inhibition disrupts pathways associated with cell senescence and SASP. In vivo studies unravel that endothelial-specific Sting deficiency alleviates aging-related endothelial inflammation and mitochondrial dysfunction and prevents the development of atherosclerosis in mice. By screening FDA-approved vasoprotective drugs, we identified Cilostazol as a new STING inhibitor that attenuates aging-related endothelial inflammation both in vitro and in vivo. We demonstrated that Cilostazol significantly inhibited STING translocation from the ER to the Golgi apparatus during STING activation by targeting S162 and S243 residues of STING. These results disclose the deleterious effects of a cfDNA-STING-SASP-cfDNA vicious circle on EC senescence and atherogenesis and suggest that the STING pathway is a promising therapeutic target for vascular aging-related diseases. A proposed model illustrates the central role of STING in mediating a vicious circle of cfDNA-STING-SASP-cfDNA to aggravate age-related endothelial inflammation and mitochondrial damage.

Spatially confined photoacoustic effects of responsive nanoassembly boosts lysosomal membrane permeabilization and immunotherapy of triple-negative breast cancer

Although immunogenic cell death (ICD) induced by lysosomal membrane permeabilization (LMP) evidently enhance the effectiveness of antitumor immunity for triple-negative breast cancer (TNBC) with poor immunogenicity, their potential is increasingly restricted by the development of other death pathways and the repair of lysosomes by endoplasmic reticulum (ER) during LMP induction. Herein, a polydopamine nanocomposite with i-motif DNA modified and BNN6 loaded is prepared toward boosting LMP and immunotherapy of TNBC by synergy of spatially confined photoacoustic (PA) effects and nitric oxide. Combining the high-frequency pulsed laser (4000 kHz) with the intra-lysosomal assembly of nanocomposites produced spatially confined and significantly boosted PA effects (4.8-fold higher than the individually dispersed particles extracellular), suppressing damage to other cellular components and selectively reducing lysosomal integrity to 19.2 %. Simultaneously, the releasing of nitric oxide inhibited the repair of lysosomes by ER stress, causing exacerbated LMP. Consequently, efficient immune activation was achieved, including the abundant releasing of CRT/HMGB1 (5.93-6.8-fold), the increasing maturation of dendritic cells (3.41-fold), and the fostered recruitment of CD4+/CD8+T cells (3.99-3.78-fold) in vivo. The study paves a new avenue for the rational design and synergy of confined energy conversion and responsive nanostructures to achieve the treatment of low immunogenicity tumors. STATEMENT OF SIGNIFICANCE: A strategy of boosting lysosomal membrane permeabilization (LMP) and concomitantly preventing the repair was developed to address the immunotherapy challenge of triple-negative breast cancer. Spatially confined and significantly enhanced photoacoustic (PA) effects were achieved through DNA-guided pH-responsive assembly of polydopamine nanocomposites in lysosomes and application of a high-frequency pulsed laser. Efficient immunogenic cell death was guaranteed by selective and powerful damage of lysosomal membranes through the significant contrast of PA intensities for dispersed/assembled particles and nitric oxide release induced endoplasmic reticulum stress. The study paves a new avenue for the rational design and synergy of confined energy conversion and responsive nanostructures to achieve the treatment of low immunogenicity tumors.

Neutrophil-Targeting Semiconducting Polymer Nanotheranostics for NIR-II Fluorescence Imaging-Guided Photothermal-NO-Immunotherapy of Orthotopic Glioblastoma

Glioblastoma (GBM) is one of the deadliest primary brain tumors, but its diagnosis and curative therapy still remain a big challenge. Herein, neutrophil-targeting semiconducting polymer nanotheranostics (SSPNiNO) is reported for second near-infrared (NIR-II) fluorescence imaging-guided trimodal therapy of orthotopic glioblastoma in mouse models. The SSPNiNO are formed based on two semiconducting polymers acting as NIR-II fluorescence probe as well as photothermal conversion agent, respectively. A thermal-responsive nitric oxide (NO) donor and an adenosine 2A receptor (A2AR) inhibitor are co-integrated into SSPNiNO to enable trimodal therapeutic actions. SSPNiNO are surface attached with a neutrophil-targeting ligand to mediate their effective delivery into orthotopic GBM sites via a "Trojan Horse" manner, enabling high-sensitive NIR-II fluorescence imaging. Upon NIR-II light illumination, SSPNiNO effectively generates heat via NIR-II photothermal effect, which not only kills tumor cells and induces immunogenic cell death (ICD), but also triggers controlled NO release to strengthen tumor ICD. Additionally, the encapsulated A2AR inhibitor can modulate immunosuppressive tumor microenvironment by blocking adenosine-A2AR pathway, which further boosts the antitumor immunological effect to observably suppress the orthotopic GBM progression. This study can provide a multifunctional theranostic nanoplatform with cumulative therapeutic actions for NIR-II fluorescence imaging-guided effective GBM treatment.

A Bimetallic Nanomodulator to Reverse Immunosuppression via Sonodynamic-Ferroptosis and Lactate Metabolism Modulation

Triple-negative breast cancer (TNBC) responds poorly to immunotherapy due to insufficient immunogenicity and highly immunosuppressive tumor microenvironment (TME). Herein, an intelligent calcium/cobalt-based nanomodulator (Ca,Co)CO3-LND-TCPP@F127-TA (abbreviated as CCLT@FT) is developed to act as a sonodynamic-ferroptosis inducer and metabolic immunoadjuvant to enhance anti-tumor immunotherapy. More details, simultaneous reactive oxygen species (ROS) generation and glutathione (GSH) depletion can be achieved due to the existence of Co2+/Co3+ redox couple in CCLT@FT. Meanwhile, mitochondrial Ca2+ overload and tetrakis(4-carboxyphenyl) porphyrin (TCPP)-mediated sonodynamic therapy (SDT) further amplify the oxidative stress and promote ferroptosis in tumor cells. More impressively, CCLT@FT can modulate lactate metabolism by doping with cobalt and loading with lonidamine (LND, an inhibitor of MCT4), thereby reversing the high-lactate immunosuppressive TME. Furthermore, the combination with immune checkpoint blockade (ICB) therapy is found to achieve superior anti-tumor immunity, which in turn promotes ferroptosis of tumor cells by downregulating SLC7A11 protein, ultimately creating a "cycle" therapy. Overall, this work demonstrates a novel strategy for enhancing anti-tumor immunotherapy based on a closed-loop enhancement therapeutic route between CCLT@FT inducing ferroptosis/lactate metabolism modulation and ICB therapy, providing an alternative and important reference for effective immunotherapy of TNBC.

Surface Oxygen Vacancies and Corona Polarization of Bi4Ti3O12 Nanosheets for Synergistically Enhanced Sonopiezoelectric Therapy

Sonopiezoelectric therapy, an ultrasound-activated piezoelectric nanomaterial for tumor treatment, has emerged as a novel alternative modality. However, the limited piezoelectric catalytic efficiency is a serious bottleneck for its practical application. Excellent piezoelectric catalysts with high piezoelectric coefficients, good deformability, large mechanical impact surface area, and abundant catalytically active sites still need to be developed urgently. In this study, the classical ferroelectric material, bismuth titanate (Bi4Ti3O12, BTO), is selected as a sonopiezoelectric sensitizer for tumor therapy. BTO generates electron-hole pairs under ultrasonic irradiation, which can react with the substrates in a sonocatalytic-driven redox reaction. Aiming to further improve the catalytic activity of BTO, modification of surface oxygen vacancies and treatment of corona polarization are envisioned in this study. Notably, modification of the surface oxygen vacancies reduces its bandgap and inhibits electron-hole recombination. Additionally, the corona polarization treatment immobilized the built-in electric field on BTO, further promoting the separation of electrons and holes. Consequently, these modifications greatly improve the sonocatalytic efficiency for in situ generation of cytotoxic ROS and CO, effectively eradicating the tumor.

H2S-Responsive NIR-II Fluorescent Nanozyme that Regulates Tumor Microenvironment for Activatable Synergistic CO Therapy/Catalytic Therapy/Immunotherapy

Nanozyme catalytic therapy triggered by the tumor microenvironment (TME)-responsive enzyme-like catalytic activities is an emerging approach for tumor treatment. However, the poor catalytic efficiency of nanozymes in tumors and the toxic side effects on normal tissues limit their further development, primarily due to the limited uptake and penetration depth of nanozyme in tumor tissues. Here, a tumor-targeting TME and electric field stimuli-responsive nanozyme (AgPt@CaCO3-FA) is developed, which is capable of catalyzing the generation of ROS to induce cell death and releasing carbon monoxide (CO) specifically in tumor tissues for on-demand CO therapy and immunotherapy. Benefiting from the endogenous H2S activated NIR-II fluorescence (FL) imaging guidance, AgPt@CaCO3-FA can be delivered into the deeper site of tumor tissues resulted from the TME regulation via generated CO during the electrolysis process to improve the catalytic efficiency of nanozymes in tumors. Moreover, CO effectively relieve immunosuppression TME via reeducating tumor-supportive M2-like macrophages to tumoricidal M1-like macrophages and induce mitochondrial dysfunction by reducing mitochondrial membrane potential, triggering tumor cells apoptosis. The enzyme-like activities combined with CO therapy arouse distinct immunogenic cell death (ICD) effect. Therefore, AgPt@CaCO3-FA permits synergistic CO gas, catalytic therapy and immunotherapy, effectively eradicating orthotopic breast tumors and preventing tumor metastasis and recurrence.

Recent strides in macromolecular targeted photodynamic therapy for cancer

The recent approval of Akalux® for antibody-targeted photodynamic therapy (PDT) in Japan (also known as photoimmunotherapy), and the recent approval of Cytalux® for folate-specific image guided surgery by the FDA have motivated the continued development of macromolecular targeted PDT for cancer management. This review spotlights some of the most recent advances in macromolecular targeted PDT since 2021, exploring the latest advances in protein engineering, adaptive macromolecular constructs and nanotechnology, adoption of immune checkpoint inhibitors, and targeting using biomimetic membranes. These strategies summarized here attempt to expand the functionality, benefit, and success of macromolecular targeting for PDT to advance the technology beyond what has already entered into the clinical realm.

Biomimetic Nanosystem Loading Aggregation-Induced Emission Luminogens and SO2 Prodrug for Inhibiting Insufficient Photothermal Therapy-Induced Breast Cancer Recurrence and Metastasis

Photothermal therapy (PTT) holds considerable clinical promise. However, insufficient PTT-induced tumor recurrence and metastasis is an urgent practical problem that needs to be solved. Herein, a biomimetic mesoporous organosilicon nano-system called PSAB is designed to precisely deplete cancer stem cells (CSCs) and prevent tumor recurrence and metastasis after PTT. The PSAB system is made up of Aggregation-induced emission (AIE)-active photothermal agent, 2TT-oC26B, and SO2 prodrug, benzothiazole sulfinate (BTS), within mesoporous organosilicon nanoparticles (MON) enclosed by an exterior platelet membrane. PSAB effectively targets CSCs both in vitro and in vivo by P-selectin/CD44 interaction. The degradation of MON and subsequent release of BTS and AIE molecules are facilitated by intracellular glutathione (GSH). Subsequently, the acidic tumor environment triggers the SO2 gas therapy from BTS. This process leads to the depletion of GSH and CSCs elimination. After combining PSAB with photothermal therapy, there is no significant tumor recurrence or metastasis. These results indicate that SO2 gas therapy and AIE-mediated PTT act synergistically to offer a unique approach for preventing tumor recurrence and metastasis after PTT, thus holding significant promise for clinical applications in cancer PTT.

Evaluation of the Ocular Safety of Hollow Mesoporous Organosilica Nanoparticles with Different Tetrasulfur Bond Content

Background

Drug therapy for eye diseases has been limited by multiple protective mechanisms of the eye, which can be improved using well-designed drug delivery systems. Mesoporous silica nanoparticles (MSNs) had been used in many studies as carriers of therapeutic agents for ocular diseases treatment. However, no studies have focused on ocular biosafety. Considering that MSNs containing tetrasulfur bonds have unique advantages and have drawn increasing attention in drug delivery systems, it is necessary to explore the ocular biosafety of tetrasulfur bonds before their widespread application as ophthalmic drug carriers.

Methods

In this study, hollow mesoporous silica nanoparticles (HMSNs) with different tetrasulfur bond contents were prepared and characterized. The ocular biosafety of HMSN-E was evaluated in vitro on the three selected ocular cell lines, including corneal epithelial cells, lens epithelial cells and retinal endothelial cells (HREC), and in vivo by using topical eye drops and intravitreal injections.

Results

In cellular experiments, HMSNs caused obvious S content-dependent cytotoxic effect. HMSNs with the highest tetrasulfur bond content (HMSN-E), showed the highest cytotoxicity among all the HMSNs, and HREC was the most vulnerable cell to HMSN-E. It was shown that HMSN-E could react with intracellular GSH to generate H2S and decrease intracellular GSH concentration. Treatment of HREC with HMSN-E increased intracellular ROS, decreased mitochondrial membrane potential, and induced cell cycle arrest at the G1/S checkpoint, finally caused apoptosis and necrosis of HREC. Topical eye drops of HMSN-E could cause corneal damage. The intravitreal injection of HMSN-E could induce inflammation in the vitreum and ganglion cell layers, resulting in vitreous opacities and retinal abnormalities.

Conclusion

The incorporation of tetrasulfur bonds into HMSN can have toxic effects on ocular tissues. Therefore, when mesoporous silica nanocarriers are designed for ophthalmic pharmaceuticals, the ocular toxicity of the tetrasulfur bonds should be considered.

Biodegradable Ruthenium-Rhenium Complexes Containing Nanoamplifiers: Triggering ROS-Induced CO Release for Synergistic Cancer Treatment

The constrained effectiveness of photodynamic therapy (PDT) has impeded its widespread use in clinical practice. Urgent efforts are needed to address the shortcomings faced in photodynamic therapy, such as photosensitizer toxicity, short half-life, and limited action range of reactive oxygen species (ROS). In this study, a biodegradable copolymer nanoamplifier is reported that contains ruthenium complex (Ru-complex) as photosensitizer (PS) and rhenium complex (Re-complex) as carbon monoxide (CO)-release molecule (CORM). The well-designed nanoamplifier brings PS and CORM into close spatial proximity, significantly promotes the utilization of light-stimulated reactive oxygen species (ROS), and cascaded amplifying CO release, thus enabling an enhanced synergistic effect of PDT and gas therapy for cancer treatment. Moreover, owing to its intrinsic photodegradable nature, the nanoamplifier exhibits good tumor accumulation and penetration ability, and excellent biocompatibility in vivo. These findings suggest that the biodegradable cascaded nanoamplifiers pave the way for a synergistic and clinically viable integration of photodynamic and gas therapy.

Light-Activated In Situ Vaccine with Enhanced Cytotoxic T Lymphocyte Infiltration and Function for Potent Cancer Immunotherapy

In situ cancer vaccination is an attractive strategy that stimulates protective antitumor immunity. Cytotoxic T lymphocytes (CTLs) are major mediators of the adaptive immune defenses, with critical roles in antitumor immune response and establishing immune memory, and are consequently extremely important for in situ vaccines to generate systemic and lasting antitumor efficacy. However, the dense extracellular matrix and hypoxia in solid tumors severely impede the infiltration and function of CTLs, ultimately compromising the efficacy of in situ cancer vaccines. To address this issue, a robust in situ cancer vaccine, Au@MnO2 nanoparticles (AMOPs), based on a gold nanoparticle core coated with a manganese dioxide shell is developed. The AMOPs modulated the unfavorable tumor microenvironment (TME) to restore CTLs infiltration and function and efficiently induced immunogenic cell death. The Mn2+-mediated stimulator of the interferon genes pathway can be activated to further augment the therapeutic efficacy of the AMOPs. Thus, the AMOPs vaccine successfully elicited long-lasting antitumor immunity to considerably inhibit primary, recurrent, and metastatic tumors. This study not only highlights the importance of revitalizing CTLs efficacy against solid tumors but also makes progress toward overcoming TME barriers for sustained antitumor immunity.

Tumor Microenvironment-Specific Driven Nanoagents for Synergistic Mitochondria Damage-Related Immunogenic Cell Death and Alleviated Immunosuppression

Despite significant breakthroughs in immunotherapy, the limitations of inadequate immune stimulation and stubborn immune resistance continue to present opportunities and challenges. Therefore, a two-pronged approach, encompassing the activation of immunogenic cell death (ICD) and blocking the indoleamine 2,3-dioxygenase (IDO)-mediated pathway, is devised to elicit systemic anti-tumor immunity and alleviate immunosuppression. Herein, a tumor microenvironment (TME)-specific driven nanoagent is composed of a tetrasulfide bond-bridged mesoporous silica layer (MON) coated up-conversion nanoparticles as a nano-carrier, combines Fe2+, curcumin, and indoximod for operating chemodynamic therapy/chemotherapy/immunotherapy. The consumption of glutathione (GSH) caused by MON degradation, the Fenton reaction of Fe2+, and curcumin triggering mitochondrial damage collectively exacerbate the oxidative stress, leading to a violent immunoreaction and reversal of the immunosuppressive TME through a combination of IDO-inhibitors. Meanwhile, upconversion luminescence (UCL) imaging serves as a significant guiding tool for drug delivery and the treatment of nanoagents. In vivo and in vitro experiment results demonstrate that the nanosystem not only effectively inhibits the growth of primary tumors but also induces immune priming and memory effects to reject re-challenged tumors. The strategy as a complementary approach displays great potential for future immunotherapy along with other multimodal treatment modes.

Codelivery of Gaseous Signaling Molecules for Biomedical Applications

Gaseous signaling molecules (GSMs) including nitric oxide (NO), carbon monoxide (CO) and hydrogen sulfide (H2S) have presented excellent therapeutic efficacy such as anti-inflammatory, anti-microbial and anti-cancer effects and multiple biomedical applications in recent years. As the three most vital signaling molecules in human physiology, these three GSMs show so intertwined and orchestrated interactions that the synergy of multiple gases may demonstrate a more complex therapeutic potential than single gas delivery. Consequently, researchers have been devoted to developing codelivery systems of GSMs by synthesizing a single molecule as a dual donor to maximize the gaseous therapeutic efficacy. In this minireview, we summarize the recent developments of molecules or materials enabling codelivery of GSMs for biomedical applications. It appears that compared with the abundant cases of codelivery of NO and H2S, research on codelivery of CO and the other two GSMs separately remains to be explored.

Phase and Defect Engineering of MoSe2 Nanosheets for Enhanced NIR-II Photothermal Immunotherapy

Inducing immunogenic cell death (ICD) during photothermal therapy (PTT) has the potential to effectively trigger photothermal immunotherapy (PTI). However, ICD induced by PTT alone is often limited by inefficient PTT, low immunogenicity of tumor cells, and a dysregulated redox microenvironment. Herein, we develop MoSe2 nanosheets with high-percentage metallic 1T phase and rich exposed active Mo centers through phase and defect engineering of MoSe2 as an effective nanoagent for PTI. The metallic 1T phase in MoSe2 nanosheets endows them with strong PTT performance, and the abundant exposed active Mo centers endow them with high activity for glutathione (GSH) depletion. The MoSe2-mediated high-performance PTT synergizing with efficient GSH depletion facilitates the release of tumor-associated antigens to induce robust ICD, thus significantly enhancing checkpoint blockade immunotherapy and activating systemic immune response in mouse models of colorectal cancer and triple-negative metastatic breast cancer.

A Near-Infrared Fluorescent Probe with Large Stokes Shift for Sensitive Detection of Hydrogen Sulfide in Environmental Water, Food Spoilage, and Biological Systems

Hydrogen sulfide (H2S) is an important endogenous gas transmitter that plays a critical role in various physiological and pathological processes and can also cause a negative impact on foodstuffs. In this study, we designed and synthesized a simple, easily available, high-yield, and low-cost near-infrared (λem = 710 nm) fluorescent probe, DEM-H2S, with a substantial Stokes shift (205 nm) for the detection of H2S. DEM-H2S features high selectivity and sensitivity (LOD = 80 nM) toward H2S, accompanied by a noticeable color change. Upon interaction with H2S, DEM-H2S exhibits a restored ICT (Intramolecular Charge Transfer) process, thereby manifesting near-infrared fluorescence. DEM-H2S has been successfully utilized to detect H2S in actual water samples and to monitor the spoilage of food items, such as pork, shrimp, and eggs. Furthermore, DEM-H2S enables the imaging of endogenous and exogenous H2S in living MCF-7 cells and zebrafish. Hence, DEM-H2S provides an attractive method for the detection of H2S in environmental, food, and biological systems, holding potential value in physiological and pathological research.

Boarding pyroptosis onto nanotechnology for cancer therapy

Pyroptosis, a non-apoptotic programmed cellular inflammatory death mechanism characterized by gasdermin (GSDM) family proteins, has gathered significant attention in the cancer treatment. However, the alarming clinical trial data indicates that pyroptosis-mediated cancer therapeutic efficiency is still unsatisfactory. It is essential to integrate the burgeoning biomedical findings and innovations with potent technology to hasten the development of pyroptosis-based antitumor drugs. Considering the rapid development of pyroptosis-driven cancer nanotherapeutics, here we aim to summarize the recent advances in this field at the intersection of pyroptosis and nanotechnology. First, the foundation of pyroptosis-based nanomedicines (NMs) is outlined to illustrate the reliability and effectiveness for the treatment of tumor. Next, the emerging nanotherapeutics designed to induce pyroptosis are overviewed. Moreover, the cross-talk between pyroptosis and other cell death modalities are discussed, aiming to explore the mechanistic level relationships to provide guidance strategies for the combination of different types of antitumor drugs. Last but not least, the opportunities and challenges of employing pyroptosis-based NMs in potential clinical cancer therapy are highlighted.

Narrow Bandgap Schottky Heterojunction Sonosensitizer with High Electron-Hole Separation Boosted Sonodynamic Therapy in Bladder Cancer

Sonodynamic therapy (SDT) is applied to bladder cancer (BC) given its advantages of high depth of tissue penetration and nontoxicity due to the unique anatomical location of the bladder near the abdominal surface. However, low electron-hole separation efficiency and wide bandgap of sonosensitizers limit the effectiveness of SDT. This study aims to develop a TiO2-Ru-PEG Schottky heterojunction sonosensitizer with high electron-hole separation and narrow bandgap for SDT in BC. Density functional theory (DFT) calculations and experiments collectively demonstrate that the bandgap of TiO2-Ru-PEG is reduced due to the Schottky heterojunction with the characteristic of crystalline-amorphous interface formed by the deposition of ruthenium (Ru) within the shell layer of TiO2. Thanks to the enhancement of oxygen adsorption and the efficient separation of electron-hole pairs, TiO2-Ru-PEG promotes the generation of reactive oxygen species (ROS) under ultrasound (US) irradiation, resulting in cell cycle arrest and apoptosis of bladder tumor cells. The in vivo results prove that TiO2-Ru-PEG boosted the subcutaneous and orthotopic bladder tumor models while exhibiting good safety. This study adopts the ruthenium complex for optimizing sonosensitizers, contributing to the progress of SDT improvement strategies and presenting a paradigm for BC therapy.

Microenvironment-Responsive Targeted Nanomedicine for a Collaborative Integration of Tumor Theranostics and Bone Defect Repair

Despite advancements in breast cancer treatment, bone metastases remain a significant concern for advanced breast cancer patients. Current theranostics strategies face challenges in integrating tumor theranostics and bone formation. Herein, this work develops an activatable targeted nanomedicine AuMnCO@BSA-N3 (AMCBN) to enable a novel collaborative integration of second near-infrared (NIR-II) fluorescence imaging guided precise theranostics for breast cancer bone metastases and osteogenic microenvironment remolding. This strategy employs a chemical coordination between noble metal complex and metal carbonyl (MnCO), with surface modification of azide groups to enhance tumor affinity through passive and active targeting. The initiated respondent behavior of AMCBN by tumor microenvironment accelerate the degradation of coordinated MnCO, resulting in a rapid release of multifunctional agents for efficient chemodynamic therapy (CDT)/gas synergistic therapy. Meanwhile, the exceptional bone-binding properties enable the efficient and controlled release of Mn2+ ions and carbon monoxide (CO) in the bone microenvironment, thereby facilitating the expression of osteogenesis-related proteins and establishing a novel synchronous theranostics process for tumor-bone repair.

A redox homeostasis disruptor based on a biodegradable nanoplatform for ultrasound (US) imaging-guided high-performance ferroptosis therapy of tumors

The synergistic disruption of intracellular redox homeostasis through the combination of ferroptosis/gas therapy shows promise in enhancing the antitumor efficacy. However, the development of an optimal delivery system encounters significant challenges, including effective storage, precise delivery, and controlled release of therapeutic gas. In this study, we propose the utilization of a redox homeostasis disruptor that is selectively activated by the tumor microenvironment (TME), in conjunction with our newly developed nanoplatforms (MC@HMOS@Au@RGD), for highly efficient ferroptosis therapy of tumors. The TME-triggered degradation of HMOS initiates the release of MC and AuNPs from the MC@HMOS@Au@RGD nanoplatform. The released MC subsequently reacts with endogenous hydrogen peroxide (H2O2) and H+ to enable the on-demand release of CO gas, leading to mitochondrial damage. Simultaneously, the released AuNPs exhibit GOx-like activity, catalyzing glucose to generate gluconic acid and H2O2. This process not only promotes the decomposition of MnCO to enhance CO production but also enhances the Fenton-like reaction between Mn2+ and H2O2, generating ROS through the modulation of the H+ and H2O2-enriched TME. Moreover, the generation of CO bubbles enables the monitoring of the ferroptosis treatment process through ultrasound (US) imaging. The efficacy of our prepared MC@HMOS@Au@RGD disruptors in ferroptosis therapy is validated through both in vitro and in vivo experiments.

Gas-Amplified Metalloimmunotherapy with Dual Activation of Pyroptosis and the STING Pathway for Remodeling the Immunosuppressive Cervical Cancer Microenvironment

The immunosuppressive microenvironment of cervical cancer significantly hampers the effectiveness of immunotherapy. Herein, PEGylated manganese-doped calcium sulfide nanoparticles (MCSP) were developed to effectively enhance the antitumor immune response of the cervical cancer through gas-amplified metalloimmunotherapy with dual activation of pyroptosis and STING pathway. The bioactive MCSP exhibited the ability to rapidly release Ca2+, Mn2+, and H2S in response to the tumor microenvironment. H2S disrupted the calcium buffer system of cancer cells by interfering with the oxidative phosphorylation pathway, leading to calcium overload-triggered pyroptosis. On the other hand, H2S-mediated mitochondrial dysfunction further promoted the release of mitochondrial DNA (mtDNA), enhancing the activation effect of Mn2+ on the cGAS-STING signaling axis and thereby activating immunosuppressed dendritic cells. The released H2S acted as an important synergist between Mn2+ and Ca2+ by modulating dual signaling mechanisms to bridge innate and adaptive immune responses. The combination of MCSP NPs and PD-1 immunotherapy achieved synergistic antitumor effects and effectively inhibited tumor growth. This study reveals the potential collaboration between H2S gas therapy and metalloimmunotherapy and provides an idea for the design of nanoimmunomodulators for rational regulation of the immunosuppressive tumor microenvironment.

Genetically Edited Cascade Nanozymes for Cancer Immunotherapy

Immune checkpoint blockade (ICB) has brought tremendous clinical progress, but its therapeutic outcome can be limited due to insufficient activation of dendritic cells (DCs) and insufficient infiltration of cytotoxic T lymphocytes (CTLs). Evoking immunogenic cell death (ICD) is one promising strategy to promote DC maturation and elicit T-cell immunity, whereas low levels of ICD induction of solid tumors restrict durable antitumor efficacy. Herein, we report a genetically edited cell membrane-coated cascade nanozyme (gCM@MnAu) for enhanced cancer immunotherapy by inducing ICD and activating the stimulator of the interferon genes (STING) pathway. In the tumor microenvironment (TME), the gCM@MnAu initiates a cascade reaction and generates abundant cytotoxic hydroxyl (•OH), resulting in improved chemodynamic therapy (CDT) and boosted ICD activation. In addition, released Mn2+ during the cascade reaction activates the STING pathway and further promotes the DC maturation. More importantly, activated immunogenicity in the TME significantly improves gCM-mediated PD-1/PD-L1 checkpoint blockade therapy by eliciting systemic antitumor responses. In breast cancer subcutaneous and lung metastasis models, the gCM@MnAu showed synergistically enhanced therapeutic effects and significantly prolonged the survival of mice. This work develops a genetically edited nanozyme-based therapeutic strategy to improve DC-mediated cross-priming of T cells against poorly immunogenic solid tumors.

Aggregation-Enabled Electrochemistry in Confined Nanopore Capable of Complementary Faradaic and Non-Faradaic Detection

Electrochemistry that empowers innovative nanoscopic analysis has long been pursued. Here, the concept of aggregation-enabled electrochemistry (AEE) in a confined nanopore is proposed and devised by reactive oxygen species (ROS)-responsive aggregation of CdS quantum dots (QDs) within a functional nanopipette. Complementary Faradaic and non-Faradaic operations of the CdS QDs aggregate could be conducted to simultaneously induce the signal-on of the photocurrents and the signal-off of the ionic signals. Such a rationale permits the cross-checking of the mutually corroborated signals and thus delivers more reliable results for single-cell ROS analysis. Combined with the rich biomatter-light interplay, the concept of AEE can be extended to other stimuli-responsive aggregations for electrochemical innovations.

Glutathione-Responsive and Hydrogen Sulfide Self-Generating Nanocages Based on Self-Weaving Technology To Optimize Cancer Immunotherapy

As an ideal drug carrier, it should possess high drug loading and encapsulation efficiency and precise drug targeting release. Herein, we utilized a template-guided self-weaving technology of phase-separated silk fibroin (SF) in reverse microemulsion (RME) to fabricate a kind of hyaluronic acid (HA) coated SF nanocage (HA-gNCs) for drug delivery of cancer immunotherapy. Due to the hollow structure, HA-gNCs were capable of simultaneous encapsulation of the anti-inflammatory drug betamethasone phosphate (BetP) and the immune checkpoint blockade (ICB) agent PD-L1 antibody (αPD-L1) efficiently. Another point worth noting was that the thiocarbonate cross-linkers used to strengthen the SF shell of HA-gNCs could be quickly broken by overexpressed glutathione (GSH) to reach responsive drug release inside tumor tissues accompanied by hydrogen sulfide (H2S) production in one step. The synergistic effect of released BetP and generated H2S guaranteed chronological modulation of the immunosuppressive tumor microenvironment (ITME) to amplify the therapeutic effect of αPD-L1 for the growth, metastasis, and recurrence of tumors. This study highlighted the exceptional prospect of HA-gNCs as a self-assistance platform for cancer drug delivery.

Aggregation induced emission dynamic chiral europium(III) complexes with excellent circularly polarized luminescence and smart sensors

The synthesis of dynamic chiral lanthanide complex emitters has always been difficult. Herein, we report three pairs of dynamic chiral EuIII complex emitters (R/S-Eu-R-1, R = Et/Me; R/S-Eu-Et-2) with aggregation-induced emission. In the molecular state, these EuIII complexes have almost no obvious emission, while in the aggregate state, they greatly enhance the EuIII emission through restriction of intramolecular rotation and restriction of intramolecular vibration. The asymmetry factor and the circularly polarized luminescence brightness are as high as 0.64 (5D0 → 7F1) and 2429 M-1cm-1 of R-Eu-Et-1, achieving a rare double improvement. R-Eu-Et-1/2 exhibit excellent sensing properties for low concentrations of CuII ions, and their detection limits are as low as 2.55 and 4.44 nM, respectively. Dynamic EuIII complexes are constructed by using chiral ligands with rotor structures or vibration units, an approach that opens a door for the construction of dynamic chiral luminescent materials.

Thiophene π-Bridge Manipulation of NIR-II AIEgens for Multimodal Tumor Phototheranostics

The fabrication of a multimodal phototheranostic platform on the basis of single-component theranostic agent to afford both imaging and therapy simultaneously, is attractive yet full of challenges. The emergence of aggregation-induced emission luminogens (AIEgens), particularly those emit fluorescence in the second near-infrared window (NIR-II), provides a powerful tool for cancer treatment by virtue of adjustable pathway for radiative/non-radiative energy consumption, deeper penetration depth and aggregation-enhanced theranostic performance. Although bulky thiophene π-bridges such as ortho-alkylated thiophene, 3,4-ethoxylene dioxythiophene and benzo[c]thiophene are commonly adopted to construct NIR-II AIEgens, the subtle differentiation on their theranostic behaviours has yet to be comprehensively investigated. In this work, systematical investigations discovered that AIEgen BT-NS bearing benzo[c]thiophene possesses acceptable NIR-II fluorescence emission intensity, efficient reactive oxygen species generation, and high photothermal conversion efficiency. Eventually, by using of BT-NS nanoparticles, unprecedented performance on NIR-II fluorescence/photoacoustic/photothermal imaging-guided synergistic photodynamic/photothermal elimination of tumors was demonstrated. This study thus offers useful insights into developing versatile phototheranostic systems for clinical trials.

An NIR-II Excitable AIE Small Molecule with Multimodal Phototheranostic Features for Orthotopic Breast Cancer Treatment

One-for-all phototheranostics, referring to a single component simultaneously exhibiting multiple optical imaging and therapeutic modalities, has attracted significant attention due to its excellent performance in cancer treatment. Benefitting from the superiority in balancing the diverse competing energy dissipation pathways, aggregation-induced emission luminogens (AIEgens) are proven to be ideal templates for constructing one-for-all multimodal phototheranostic agents. However, to this knowledge, the all-round AIEgens that can be triggered by a second near-infrared (NIR-II, 1000-1700 nm) light have not been reported. Given the deep tissue penetration and high maximum permissible exposure of the NIR-II excitation light, herein, this work reports for the first time an NIR-II laser excitable AIE small molecule (named BETT-2) with multimodal phototheranostic features by taking full use of the advantage of AIEgens in single molecule-facilitated versatility as well as synchronously maximizing the molecular donor-acceptor strength and conformational distortion. As formulated into nanoparticles (NPs), the high performance of BETT-2 NPs in NIR-II light-driven fluorescence-photoacoustic-photothermal trimodal imaging-guided photodynamic-photothermal synergistic therapy of orthotopic mouse breast tumors is fully demonstrated by the systematic in vitro and in vivo evaluations. This work offers valuable insights for developing NIR-II laser activatable one-for-all phototheranostic systems.

In situ bio-mineralized Mn nanoadjuvant enhances anti-influenza immunity of recombinant virus-like particle vaccines

Virus like particles (VLPs) have been well recognized as one of the most important vaccine platforms due to their structural similarity to natural viruses to induce effective humoral and cellular immune responses. Nevertheless, lack of viral nucleic acids in VLPs usually leads the vaccine candidates less efficient in provoking innate immune against viral infection. Here, we constructed a biomimetic dual antigen hybrid influenza nanovaccines THM-HA@Mn with robust immunogenicity via in situ synthesizing a stimulator of interferon genes (STING) agonist Mn3O4 inside the cavity of a recombinant Hepatitis B core antigen VLP (HBc VLP) having fused SpyTag and influenza M2e antigen peptides (Tag-HBc-M2e, THM for short), followed by conjugating a recombinant hemagglutinin (rHA) antigen on the surface of the nanoparticles through SpyTag/SpyCatcher ligating. Such inside Mn3O4 immunostimulator-outside rHA antigen design, together with the chimeric M2e antigen on the HBc skeleton, enabled the synthesized hybrid nanovaccines THM-HA@Mn to well imitate the spatial distribution of M2e/HA antigens and immunostimulant in natural influenza virus. In vitro cellular experiments indicated that compared with the THM-HA antigen without Mn3O4 and a mixture vaccine consisting of THM-HA + MnOx, the THM-HA@Mn hybrid nanovaccines showed the highest efficacies in dendritic cells uptake and in promoting BMDC maturation, as well as inducing expression of TNF-α and type I interferon IFN-β. The THM-HA@Mn also displayed the most sustained antigen release at the injection site, the highest efficacies in promoting the DC maturation in lymph nodes and germinal center B cells activation in the spleen of the immunized mice. The co-delivery of immunostimulant and antigens enabled the THM-HA@Mn nanovaccines to induce the highest systemic antigen-specific antibody responses and cellular immunogenicity in mice. Together with the excellent colloid dispersion stability, low cytotoxicity, as well as good biosafety, the synthetic hybrid nanovaccines presented in this study offers a promising strategy to design VLP-based vaccine with robust natural and adaptive immunogenicity against emerging viral pathogens.

Overcoming neutrophil-induced immunosuppression in postoperative cancer therapy: Combined sialic acid-modified liposomes with scaffold-based vaccines

Immunotherapy is a promising approach for preventing postoperative tumor recurrence and metastasis. However, inflammatory neutrophils, recruited to the postoperative tumor site, have been shown to exacerbate tumor regeneration and limit the efficacy of cancer vaccines. Consequently, addressing postoperative immunosuppression caused by neutrophils is crucial for improving treatment outcomes. This study presents a combined chemoimmunotherapeutic strategy that employs a biocompatible macroporous scaffold-based cancer vaccine (S-CV) and a sialic acid (SA)-modified, doxorubicin (DOX)-loaded liposomal platform (DOX@SAL). The S-CV contains whole tumor lysates as antigens and imiquimod (R837, Toll-like receptor 7 activator)-loaded PLGA nanoparticles as immune adjuvants for cancer, which enhance dendritic cell activation and cytotoxic T cell proliferation upon localized implantation. When administered intravenously, DOX@SAL specifically targets and delivers drugs to activated neutrophils in vivo, mitigating neutrophil infiltration and suppressing postoperative inflammatory responses. In vivo and vitro experiments have demonstrated that S-CV plus DOX@SAL, a combined chemo-immunotherapeutic strategy, has a remarkable potential to inhibit postoperative local tumor recurrence and distant tumor progression, with minimal systemic toxicity, providing a new concept for postoperative treatment of tumors.

In vivo visualization of tumor-associated macrophages re-education by photoacoustic/fluorescence dual-modal imaging with a metal-organic frames-based caspase-1 nanoreporter

Tumor-associated macrophages (TAMs) are vital in the tumor microenvironment, contributing to immunosuppression and therapy tolerance. Despite their importance, the precise re-education of TAMs in vivo continues to present a formidable challenge. Moreover, the lack of real-time and efficient methods to comprehend the spatiotemporal kinetics of TAMs repolarization remains a significant hurdle, severely hampering the accurate assessment of treatment efficacy and prognosis. Herein, we designed a metal-organic frameworks (MOFs) based Caspase-1 nanoreporter (MCNR) that can deliver a TLR7/8 agonist to the TAMs and track time-sensitive Caspase-1 activity as a direct method to monitor the initiation of immune reprogramming. This nanosystem exhibits excellent TAMs targeting ability, enhanced tumor accumulation, and stimuli-responsive behavior. By inducing the reprogramming of TAMs, they were able to enhance T-cell infiltration in tumor tissue, resulting in inhibited tumor growth and improved survival in mice model. Moreover, MCNR also serves as an activatable photoacoustic and fluorescent dual-mode imaging agent through Caspase-1-mediated specific enzyme digestion. This feature enables non-invasive and real-time antitumor immune activation monitoring. Overall, our findings indicate that MCNR has the potential to be a valuable tool for tumor immune microenvironment remodeling and noninvasive quantitative detection and real-time monitoring of TAMs repolarization to immunotherapy in the early stage.

Nanocatalytic Anti-Tumor Immune Regulation

Immunotherapy has brought a new dawn for human being to defeat cancer. Although existing immunotherapy regimens (CAR-T, etc.) have made breakthroughs in the treatments of hematological cancer and few solid tumors such as melanoma, the therapeutic efficacy on most solid tumors is still far from being satisfactory. In recent years, the researches on tumor immunotherapy based on nanocatalytic materials are under rapid development, and significant progresses have been made. Nanocatalytic medicine has been demonstrated to be capable of overcoming the limitations of current clinicnal treatments by using toxic chemodrugs, and exhibits highly attractive advantages over traditional therapies, such as the enhanced and sustained therapeutic efficacy based on the durable catalytic activity, remarkably reduced harmful side-effects without using traditional toxic chemodrugs, and so on. Most recently, nanocatalytic medicine has been introduced in the immune-regulation for disease treatments, especially, in the immunoactivation for tumor therapies. This article presents the most recent progresses in immune-response activations by nanocatalytic medicine-initiated chemical reactions for tumor immunotherapy, and elucidates the mechanism of nanocatalytic medicines in regulating anti-tumor immunity. By reviewing the current research progress in the emerging field, this review will further highlight the great potential and broad prospects of nanocatalysis-based anti-tumor immune-therapeutics.

Self-Adjuvanting Polyguanidine Nanovaccines for Cancer Immunotherapy

Tapping into the innate immune system's power, nanovaccines can induce tumor-specific immune responses, which is a promising strategy in cancer immunotherapy. However, traditional vaccine design, requiring simultaneous loading of antigens and adjuvants, is complex and poses challenges for mass production. Here, we developed a tumor nanovaccine platform that integrates adjuvant functions into the delivery vehicle, using branched polyguanidine (PolyGu) nanovaccines. These nanovaccines were produced by modifying polyethylenimine (PEI) with various guanidine groups, transforming PEI's cytotoxicity into innate immune activation. The PolyGu nanovaccines based on poly(phenyl biguanidine ) (Poly-PBG) effectively stimulated dendritic cells, promoted their maturation via the TLR4 and NLRP3 pathways, and displayed robust in vivo immune activity. They significantly inhibited tumor growth and extended mouse survival. The PolyGu also showed promise for constructing more potent mRNA-based nanovaccines, offering a platform for personalized cancer vaccine. This work advances cancer immunotherapy toward potential clinical application by introducing a paradigm for developing self-adjuvanting nanovaccines.

A biomimetic cuproptosis amplifier for targeted NIR-II fluorescence/photoacoustic imaging-guided synergistic NIR-II photothermal immunotherapy

The therapeutic efficacy of cuproptosis combined with phototheranostics is still hindered by easy copper efflux, nonspecific accumulation and limited light penetration depth. Here, a high-performance NIR-II semiconductor polymer was first synthesized through dual-donor engineering. Then a biomimetic cuproptosis amplifier (PCD@CM) was prepared by Cu(II)-mediated coordinative self-assembly of NIR-II ultrasmall polymer dots and the chemotherapeutic drug DOX, followed by camouflaging of tumor cell membranes. After homologous targeting delivery to tumor cells, overexpressed GSH in the tumor microenvironment (TME) triggers the disassembly of the amplifier and the release of therapeutic components through the reduction of Cu(II) to Cu(I), which enable NIR-II fluorescence/photoacoustic imaging-guided NIR-II photothermal therapy (PTT) and chemotherapy. The released Cu(I) induces the aggregation of lipoylated mitochondrial proteins accompanied by the loss of iron-sulfur proteins, leading to severe proteotoxic stress and eventually cuproptosis. NIR-II PTT and GSH depletion render tumor cells more sensitive to cuproptosis. The amplified cuproptosis sensitization provokes significant immune surveillance, triggering the immunogenic cell death (ICD) to promote cytotoxic T lymphocyte infiltration together with aPD-L1-mediated immune checkpoint blockade. This work proposes a new strategy to develop cuproptosis sensitization systems enhanced by NIR-II phototheranostics with homologous targeting and anti-tumor immune response capabilities.

Engineered macrophage-derived cellular vesicles for NIR-II fluorescence imaging-guided precise cancer photo-immunotherapy

Significant progress has been made in cancer immunotherapy; however, challenges such as interpatient variability, limited treatment response, and severe side effects persist. Although nanoimmunotherapy has emerged as a promising approach, the construction of precise and efficient nanosystems remain formidable challenges. Herein, a multifunctional nanoplatform was developed using macrophage-derived cellular vesicles (MCVs) for NIR-II imaging-guided precise cancer photo-immunotherapy. MCVs exhibited excellent tumor targeting and TAMs re-education effects, serving as both delivery carriers and therapeutic agents. Through amide bond, indocyanine green (ICG) was conjugated to the surface of MCVs, enabling in vivo tracking of MCVs distribution. Notably, ICG exhibited dual functionality as a NIR-II fluorescent agent and possessed photodynamic and photothermal effects, enabling the conversion of light energy into chemical or heat energy to eliminate tumor cells. This precision phototherapy triggered immunogenic cell death (ICD) of tumor, thereby activating the anti-tumor immune response. Additionally, MCVs loaded with R848, a toll-like receptor agonist, augmented the ICD-induced anti-tumor immunity. Animal experiments confirmed that MCVs-mediated photoimmunotherapy promoted T cell infiltration, inhibited tumor growth, and improved survival rates. In conclusion, we have developed a promising precision immunotherapy strategy capable of enhancing the immune response while mitigating off-target effects. These findings offer encouraging prospects for clinical translation.

Single-Cell Analysis Reveals Cxcl14+ Fibroblast Accumulation in Regenerating Diabetic Wounds Treated by Hydrogel-Delivering Carbon Monoxide

Nonhealing skin wounds are a problematic complication associated with diabetes. Therapeutic gases delivered by biomaterials have demonstrated powerful wound healing capabilities. However, the cellular responses and heterogeneity in the skin regeneration process after gas therapy remain elusive. Here, we display the benefit of the carbon monoxide (CO)-releasing hyaluronan hydrogel (CO@HAG) in promoting diabetic wound healing and investigate the cellular responses through single-cell transcriptomic analysis. The presented CO@HAG demonstrates wound microenvironment responsive gas releasing properties and accelerates the diabetic wound healing process in vivo. It is found that a new cluster of Cxcl14+ fibroblasts with progenitor property is accumulated in the CO@HAG-treated wound. This cluster of Cxcl14+ fibroblasts is yet unreported in the skin regeneration process. CO@HAG-treated wound macrophages feature a decrease in pro-inflammatory property, while their anti-inflammatory property increases. Moreover, the TGF-β signal between the pro-inflammatory (M1) macrophage and the Cxcl14+ fibroblast in the CO@HAG-treated wound is attenuated based on cell-cell interaction analysis. Our study provides a useful hydrogel-mediated gas therapy method for diabetic wounds and new insights into cellular events in the skin regeneration process after gas-releasing biomaterials therapy.

Liposome-coated nanoparticle triggers prostate cancer ferroptosis through synergetic chemodynamic-gas therapy

Ferroptosis has attracted much attention for tumor treatment. It has been recently identified that castration-resistant prostate cancer (CRPC) is vulnerable to ferroptosis inducers. Notably, chemodynamic therapy (CDT), triggered by metal ions, could easily induce ferroptosis via a Fenton/Fenton-like reaction, but its efficiency was highly dependent on the intracellular H2O2 concentration, posing significant changes for its clinical translation. Herein, we attached glucose oxidase (GOx) onto the surface of manganese sulfide (MnS) and developed therapeutic nanocomposites (Lpo@MnS-GOx) after encapsulating with liposome. Upon internalization by cancer cells, the released GOx could transform glucose into gluconic acid (GA) and H2O2. Notably, the generated GA stimulates the degradation of MnS, followed by the promotion of the release of H2S and Mn2+, whereas the produced H2O2 can amplify the Fenton-like response initiated by Mn2+. The enhanced CDT combined with the gas therapy effect could simultaneously promote the accumulation of reactive oxygen species and finally induce ferroptosis and exhibit an excellent anti-tumor effect. Consequently, these Lpo@MnS-GOx NPs with enhanced ferroptosis-induced effect will find great potential for CRPC cancer treatment.

Biomimetic Copper-Doped Polypyrrole Nanoparticles for Enhanced Cancer Low-Temperature Photothermal Therapy

Introduction

Photothermal therapy (PTT) has a significant potential for its application in precision tumour therapy. However, PTT-induced hyperthermia may damage healthy tissues and trigger the expression of heat shock proteins (HSPs), thereby compromising the long-term therapeutic efficacy of PTT.

Methods

In this study, a biomimetic drug delivery system comprising CuP nanozymes as the inner core and platelet membrane (PM) as the outer shell was successfully developed for administering synergistic chemodynamic therapy and mild PTT. PM is encapsulated on CuP to form this biomimetic nanoparticle (PM-coated CuP nanoparticles, PC). PC possesses peroxidase (POD) activity, can facilitate the conversion of hydrogen peroxide into ·OH, thereby inhibiting the expression of HSPs.

Results

Upon exposure to low-power laser irradiation (0.5 W/cm2, 1064 nm), PC can convert near-infrared II laser energy into heat energy, thereby enabling the administration of enhanced mild PTT. In vitro and in vivo experiments have demonstrated that this synergistic approach can induce over 90% tumour eradication with favourable biocompatibility.

Discussion

PC exhibits high efficacy and biocompatibility, making it a promising candidate for future applications.

Bioorthogonal Guided Activation of cGAS-STING by AIE Photosensitizer Nanoparticles for Targeted Tumor Therapy and Imaging

Photodynamic therapy (PDT) and photothermal therapy (PTT) leverage reactive oxygen species (ROS) and control local hyperthermia by photosensitizer to perturb intracellular redox equilibrium, inducing DNA damage in both mitochondria and nucleus, activating the cGAS-STING pathway, ultimately eliciting antitumor immune responses. However, current photosensitizers are encumbered by limitations such as suboptimal tumor targeting, aggregation-caused quenching (ACQ), and restricted excitation and emission wavelengths. Here, this work designs novel nanoparticles based on aggregation-induced emission (AIE) photosensitizer (BODTPE) for targeted tumor therapy and near-infrared II fluorescence imaging (NIR-II FLI) with enhanced PDT/PTT effects. BODTPE is employed as a monomer, dibenzocyclooctyne (DBCO)-PEG2k -amine serving as an end-capping polymer, to synthesize a BODTPE-containing polymer (DBD). Further, through self-assembly, DBD and mPEG-DSPE2k combined to form nanoparticles (NP-DBD). Notably, the DBCO on the surface of NP-DBD can react with azide groups on cancer cells pretreated with Ac4 ManNAz through a copper-free click reaction. This innovative formulation led to targeted accumulation of NP-DBD within tumor sites, a phenomenon convincingly demonstrated in murine tumor models subjected to N-azidoacetylmannosamine-tetraacylated (Ac4 ManNAz) pretreatment. Significantly, NP-DBD exhibits a multifaceted effect encompassing PDT/PTT/NIR-II FLI upon 808 nm laser irradiation, thereby better activating the cGAS-STING pathway, culminating in a compelling tumor inhibition effect augmented by robust immune modulation.

A tetrasulfide bond-bridged mesoporous organosilica-based nanoplatform for triple-enhanced chemodynamic therapy combined with chemotherapy and H2S therapy

The high glutathione (GSH) concentration and insufficient H2O2 content in tumor cells strongly constrict the efficacy of Fenton reaction-based chemodynamic therapy (CDT). Despite numerous efforts, it still remains a formidable challenge for achieving satisfactory efficacy using CDT alone. Herein, an intelligent tetrasulfide bond-bridged mesoporous organosilica-based nanoplatform that integrates GSH-depletion, H2S generation, self-supplied H2O2, co-delivery of doxorubicin (DOX) and Fenton reagent Fe2+ is presented for synergistic triple-enhanced CDT/chemotherapy/H2S therapy. Because the tetrasulfide bond is sensitive to GSH, the nanoplatform can effectively consume GSH, leading to ROS accumulation and H2S generation in the GSH-overexpressed tumor microenvironment. Meanwhile, tetrasulfide bond-induced GSH-depletion triggers the degradation of nanoparticles and the release of DOX and Fe2+. Immediately, Fe2+ catalyzes endogenous H2O2 to highly toxic hydroxyl radicals (˙OH) for CDT, and H2S induces mitochondria injury and causes energy deficiency. Of note, H2S can also decrease the decomposition of H2O2 to augment CDT by downregulating catalase. DOX elicits chemotherapy and promotes H2O2 production to provide a sufficient substrate for enhanced CDT. Importantly, the GSH depletion significantly weakens the scavenging effect on the produced ˙OH, guaranteeing the enhanced and highly efficient CDT. Based on the synergistic effect of triple-augmented CDT, H2S therapy and DOX-mediated chemotherapy, the treatment with this nanoplatform gives rise to a superior antitumor outcome.

A Stable Open-Shell Conjugated Diradical Polymer with Ultra-High Photothermal Conversion Efficiency for NIR-II Photo-Immunotherapy of Metastatic Tumor

Massive efforts have been concentrated on the advance of eminent near-infrared (NIR) photothermal materials (PTMs) in the NIR-II window (1000-1700 nm), especially organic PTMs because of their intrinsic biological safety compared with inorganic PTMs. However, so far, only a few NIR-II-responsive organic PTMs was explored, and their photothermal conversion efficiencies (PCEs) still remain relatively low. Herein, donor-acceptor conjugated diradical polymers with open-shell characteristics are explored for synergistically photothermal immunotherapy of metastatic tumors in the NIR-II window. By employing side-chain regulation, the conjugated diradical polymer TTB-2 with obvious NIR-II absorption was developed, and its nanoparticles realize a record-breaking PCE of 87.7% upon NIR-II light illustration. In vitro and in vivo experiments demonstrate that TTB-2 nanoparticles show good tumor photoablation with navigation of photoacoustic imaging in the NIR-II window, without any side-effect. Moreover, by combining with PD-1 antibody, the pulmonary metastasis of breast cancer is high-effectively prevented by the efficient photo-immunity effect. Thus, this study explores superior PTMs for cancer metastasis theranostics in the NIR-II window, offering a new horizon in developing radical-characteristic NIR-II photothermal materials.

Biocompatible Polymer-Modified Nanoplatform for Ferroptosis-Enhanced Combination Cancer Therapy

Ferroptosis is a novel type of iron-dependent non-apoptotic pathway that regulates cell death and shows unique mechanisms including causing lipid peroxide accumulation, sensitizing drug-resistant cancers, priming immunity by immunogenic cell death, and cooperatively acting with other anticancer modalities for eradicating aggressive malignancies and tumor relapse. Recently, there has been a great deal of effort to design and develop anticancer biocompatible polymeric nanoplatforms including polypeptide and PEGylated ones to achieve effective ferroptosis therapy (FT) and synergistic combination therapies including chemotherapy (CT), photodynamic therapy (PDT), sonodynamic therapy (SDT), photothermal therapy (PTT), gas therapy (GT) including nitric oxide (NO), carbon monoxide (CO), and hydrogen sulfide (H2 S), and immunotherapy (IT). To be noted, the combo therapies such as FT-CT, FT-PTT, FT-GT, and FT-IT are attracting much efforts to fight against intractable and metastatic tumors as they can generate synergistic antitumor effects and immunogenic cell death (ICD) effects or modulate immunosuppressive tumor microenvironments to initiate strong antitumor immunity and memory effects. The polymeric Fenton nano-agents with good biosafety and high anticancer efficacy will provide a guarantee for their applications. In this review, various biocompatible polymer-modified nanoplatforms designed for FT and combo treatments are summarized for anticancer therapies and discussed for potential clinical transitions.

An autocatalytic multicomponent DNAzyme nanomachine for tumor-specific photothermal therapy sensitization in pancreatic cancer

Multicomponent deoxyribozymes (MNAzymes) have great potential in gene therapy, but their ability to recognize disease tissue and further achieve synergistic gene regulation has rarely been studied. Herein, Arginylglycylaspartic acid (RGD)-modified Distearyl acylphosphatidyl ethanolamine (DSPE)-polyethylene glycol (PEG) (DSPE-PEG-RGD) micelle is prepared with a DSPE hydrophobic core to load the photothermal therapy (PTT) dye IR780 and the calcium efflux pump inhibitor curcumin. Then, the MNAzyme is distributed into the hydrophilic PEG layer and sealed with calcium phosphate through biomineralization. Moreover, RGD is attached to the outer tail of PEG for tumor targeting. The constructed nanomachine can release MNAzyme and the cofactor Ca2+ under acidic conditions and self-assemble into an active mode to cleave heat shock protein (HSP) mRNA by consuming the oncogene miRNA-21. Silencing miRNA-21 enhances the expression of the tumor suppressor gene PTEN, leading to PTT sensitization. Meanwhile, curcumin maintains high intracellular Ca2+ to further suppress HSP-chaperone ATP by disrupting mitochondrial Ca2+ homeostasis. Therefore, pancreatic cancer is triple-sensitized to IR780-mediated PTT. The in vitro and in vivo results show that the MNAzyme-based nanomachine can strongly regulate HSP and PTEN expression and lead to significant pancreatic tumor inhibition under laser irradiation.

Biomimetic nanovaccine-mediated multivalent IL-15 self-transpresentation (MIST) for potent and safe cancer immunotherapy

Cytokine therapy, involving interleukin-15 (IL-15), is a promising strategy for cancer immunotherapy. However, clinical application has been limited due to severe toxicity and the relatively low immune response rate, caused by wide distribution of cytokine receptors, systemic immune activation and short half-life of IL-15. Here we show that a biomimetic nanovaccine, developed to co-deliver IL-15 and an antigen/major histocompatibility complex (MHC) selectively targets IL-15 to antigen-specific cytotoxic T lymphocytes (CTL), thereby reducing off-target toxicity. The biomimetic nanovaccine is composed of cytomembrane vesicles, derived from genetically engineered dendritic cells (DC), onto which IL-15/IL-15 receptor α (IL-15Rα), tumor-associated antigenic (TAA) peptide/MHC-I, and relevant costimulatory molecules are simultaneously anchored. We demonstrate that, in contrast to conventional IL-15 therapy, the biomimetic nanovaccine with multivalent IL-15 self-transpresentation (biNV-IL-15) prolonged blood circulation of the cytokine with an 8.2-fold longer half-life than free IL-15 and improved the therapeutic window. This dual targeting strategy allows for spatiotemporal manipulation of therapeutic T cells, elicits broad spectrum antigen-specific T cell responses, and promotes cures in multiple syngeneic tumor models with minimal systemic side effects.