Piezoelectric Catalysis Induces Tumor Cell Senescence to Boost Chemo-Immunotherapy.

Cellular senescence, a vulnerable state of growth arrest, has been regarded as a potential strategy to weaken the resistance of tumor cells, leading to dramatic improvements in treatment efficacy. However, a selective and efficient strategy for inducing local tumor cellular senescence has not yet been reported. Herein, piezoelectric catalysis is utilized to reduce intracellular NAD+ to NADH for local tumor cell senescence for the first time. In detail, a biocompatible nanomedicine (BTO/Rh-D@M) is constructed by wrapping the piezoelectric BaTiO3/(Cp*RhCl2)2 (BTO/Rh) and doxorubicin (DOX) in the homologous cytomembrane with tumor target. After tumors are stimulated by ultrasound, negative and positive charges are generated on the BTO/Rh by piezoelectric catalysis, which reduce the intracellular NAD+ to NADH for cellular senescence and oxidize H2O to reactive oxygen species (ROS) for mitochondrial damage. Thus, the therapeutic efficacy of tumor immunogenic cell death-induced chemo-immunotherapy is boosted by combining cellular senescence, DOX, and ROS. The results indicate that 23.9% of the piezoelectric catalysis-treated tumor cells senesced, and solid tumors in mice disappeared completely after therapy. Collectively, this study highlights a novel strategy to realize cellular senescence utilizing piezoelectric catalysis and the significance of inducing tumor cellular senescence to improve therapeutic efficacy.

Flexocatalysis Enhances Tumor Photodynamic Therapy.

Photodynamic therapy (PDT) is long-standing suffered from elevated tumor interstitial fluid pressure (TIFP) and prevalent hypoxic microenvironment within the solid malignancies. Herein, sound-activated flexocatalysis is developed to overcome the dilemma of PDT through both enhancing tumor penetration of photosensitizers by reducing TIFP and establishing an oxygen-rich microenvironment. In detail, a Schottky junction is constructed by flexocatalyst MoSe2 nanoflowers and Pt. Subsequently, the Schottky junction is loaded with the photosensitizer indocyanine green (ICG) and encapsulated within tumor cytomembrane to constitute a bionic-flexocatalytic nanomedicine (MPI@M). After targeting the tumor, MPI@M orchestrates flexocatalytic water splitting in tumor interstitial fluid under acoustic stimulation to lower TIFP, which boosted the tumor penetration of ICG. Concurrently, the oxygen released from the flexocatalytic water splitting overcomes the limitation of hypoxia against PDT. Furthermore, superfluous singlet oxygen generated by PDT can induce mitochondrial dysfunction for further tumor cell apoptosis. After 60 min of flexocatalysis, both the 30% decrease of TIFP and the relieved tumor hypoxia are observed, significantly promoting the therapeutic effect of PDT. Consequently, MoSe2/Pt junction nanoflowers, with the excellent flexocatalytic performance, hold significant potential for future applications in biocatalytic cancer therapies.

Achieving deep intratumoral penetration and multimodal combined therapy for tumor through algal photosynthesis.

BACKGROUND: Elevated interstitial fluid pressure within tumors, resulting from impaired lymphatic drainage, constitutes a critical barrier to effective drug penetration and therapeutic outcomes. RESULTS: In this study, based on the photosynthetic characteristics of algae, an active drug carrier (CP@ICG) derived from Chlorella pyrenoidosa (CP) was designed and constructed. Leveraging the hypoxia tropism and phototropism exhibited by CP, we achieved targeted transport of the carrier to tumor sites. Additionally, dual near-infrared (NIR) irradiation at the tumor site facilitated photosynthesis in CP, enabling the breakdown of excessive intratumoral interstitial fluid by generating oxygen from water decomposition. This process effectively reduced the interstitial pressure, thereby promoting enhanced perfusion of blood into the tumor, significantly improving deep-seated penetration of chemotherapeutic agents, and alleviating tumor hypoxia. CONCLUSIONS: CP@ICG demonstrated a combined effect of photothermal/photodynamic/starvation therapy, exhibiting excellent in vitro/in vivo anti-tumor efficacy and favorable biocompatibility. This work provides a scientific foundation for the application of microbial-enhanced intratumoral drug delivery and tumor therapy.

Green dual-template synthesis of AgPd core-shell nanoparticles with enhanced electrocatalytic activity.

A key challenge in developing an ethanol oxidation reaction is nontoxic fabrication of highly active stable and low-cost catalysts. Here we design a green synthetic strategy of AgPd bimetallic nanosphere by a dual-template cascade method. The Pd nanoshell is firstly prepared using Vapreotide acetate as a primary template, and then the Ag nanoshell acts as a secondary template for the distribution of AgPd alloy nanoparticles. The AgPd nanoparticles have core-shell structures and various sizes, and their shell thicknesses are tuned by controlling the amount of PdCl2. The six different samples are prepared, named AgPd-1, AgPd-2, AgPd-3, AgPd-4, AgPd-5, and AgPd-6, respectively. The mass current density of AgPd-5, is higher 3.87 times that of commercial Pd/C, and exhibits the best ethanol oxidation reaction activity and long-term stability. The main reasons are that the AgPd-5 possessed excellent specific surface area due to their rough structure, and Ag can remove more CO-like species. This is the first time a Vapreotide acetate/Ag-template method has been used to synthesize a AgPd core-shell structure, which would have broad application prospects for direct ethanol fuel cells.

Direct synthesis of ultralong platinum nanowires with prominent electrocatalytic performance using lanreotide biotemplate.

Due to the dependence on the morphology, size and composition of Pt-based nanomaterials on their catalytic properties, rational design can improve the utilization efficiency and catalytic performance of Pt. As inspired by this, the ultralong Pt nanowires (ULPtNWs) with a diameter of 25 nm were prepared by a mild, green and direct peptide mediated biological template method. Impressively, ULPtNWs with a large electrochemical active surface area (57.2 m2 g-1) were obtained, exhibiting that the peak current density for the methanol oxidation was approximately three-fold better than commercial Pt/C catalyst owing to the high aspect ratio (1.6 × 103 or more). Additionally, the excellent poison resistance of the product was demonstrated, which can be attributed to the high (111) plane. These enhancements indicate that ULPtNWs as a promising catalyst have broad application prospects in the field of direct methanol fuel cells or other electrocatalysis.

Trimodal synergistic antitumor drug delivery system based on graphene oxide.

A multifunctional antitumor drug delivery system was synthesized based on graphene oxide (GO) for near-infrared (NIR) light controlling chemotherapeutic/photothermal (PTT) /photodynamic (PDT) trimodal synergistic therapy. The system named ICG-Wed-GO was formed by co-loading wedelolactone (Wed) and indocyanine green (ICG) on the surface of GO through π-π stacking interaction. Under NIR laser irradiation, ICG-Wed-GO could effectively absorb and transform optical energy to heat, generate reactive oxygen species (ROS) to ablating and damage tumor cells. The temperature of ICG-Wed-GO solution reached up to 79.4 °C in 10 min with NIR irradiation. In in vitro and in vivo study, ICG-Wed-GO showed excellent antitumor effect. After 14-day treatment of ICG-Wed-GO with NIR laser irradiation, the tumor disappeared completely on tumor-bearing mice. The low biotoxicity of ICG-Wed-GO was also proved. The system achieved the synergistic trimodal chemotherapeutic/photothermal/photodynamic treatment and demonstrated excellent antitumor effect, which is expected to have a greater potential for cancer therapy.

Gold-nanobranched-shell based drug vehicles with ultrahigh photothermal efficiency for chemo-photothermal therapy.

Development of combined chemo-photothermal nanoplatform is of great interest for enhancing antitumor efficacy. Herein, a multifunctional drug delivery system was synthesized based on gold-nanobranched coated betulinic acid liposomes (GNBS-BA-Lips) for chemo-photothermal synergistic therapy. In this system, GNBS-BA-Lips exhibited broad near-infrared (NIR) absorption, preferable photothermal response and good photostability under NIR irradiation. Importantly, the gold-nanobranched nanostructure possessed high photothermal conversion efficiency (η = 55.7%), and the temperature change (ΔT) reached 43.2 °C after laser irradiation for 5 min. Upon NIR irradiation, the nanocarriers apparently endowed higher cell uptake, resulting in an enhanced intracellular drug accumulation. Furthermore, the tumor growth inhibition ratio achieved from chemo-photothermal therapy of GNBS-BA-Lips was 86.9 ±â€¯1.1%, which was higher than that of the chemotherapy or photothermal therapy alone, showing an outstanding synergistic anticancer effect. Our data suggested that the nanoplatform should be considered as a critical platform in the development of cancer multi-mode therapies.

Doxorubicin/gold nanoparticles coated with liposomes for chemo-photothermal synergetic antitumor therapy.

Hybrid liposome/metal nanoparticles are promising candidate drug-carriers for therapy of various diseases due to their unique photothermal effect. In this study, self-crystallized gold nanoparticles (Au NPs) and doxorubicin (DOX) were co-encapsulated within liposomes (Au/DOX-Lips) by thin film hydration and gel separation technology. The surface plasmon resonance bands of drug-carriers were controllable in the near-infrared (NIR) zone. When the complex liposome/metallic hybrids were irradiated by NIR light, they displayed higher endocytosis efficiency following the fracture of liposomal membranes and the release of Au NPs. Then, the Au NPs penetrated further into deeper tumor tissue to accomplish photothermal treatment. The Au/DOX-Lips showed an excellent antitumor effect, whose inhibition rate for tumor cells was up to 78.28%. In experiments on mice bearing tumors, the Au/DOX-Lips treated mice exhibited superior tumor suppression. This novel drug system provides huge potential for biomedical application.

Advancing piezoelectric 2D nanomaterials for applications in drug delivery systems and therapeutic approaches.

Precision drug delivery and multimodal synergistic therapy are crucial in treating diverse ailments, such as cancer, tissue damage, and degenerative diseases. Electrodes that emit electric pulses have proven effective in enhancing molecule release and permeability in drug delivery systems. Moreover, the physiological electrical microenvironment plays a vital role in regulating biological functions and triggering action potentials in neural and muscular tissues. Due to their unique noncentrosymmetric structures, many 2D materials exhibit outstanding piezoelectric performance, generating positive and negative charges under mechanical forces. This ability facilitates precise drug targeting and ensures high stimulus responsiveness, thereby controlling cellular destinies. Additionally, the abundant active sites within piezoelectric 2D materials facilitate efficient catalysis through piezochemical coupling, offering multimodal synergistic therapeutic strategies. However, the full potential of piezoelectric 2D nanomaterials in drug delivery system design remains underexplored due to research gaps. In this context, the current applications of piezoelectric 2D materials in disease management are summarized in this review, and the development of drug delivery systems influenced by these materials is forecast.

A universal nanoreactor triggering butterfly effect for encouraging Fenton/Fenton-like reactions and chemodynamic therapy.

Fenton/Fenton-like reaction induced chemical dynamic therapy (CDT) has been widely recognized in tumor therapy. Due to the low efficiency of conversion from high-valent metal ions (M(n+1)+) to low-valent ions (Mn+) in the Fenton/Fenton-like catalytic process, enhancing the conversion efficiency safely and effectively would create a great opportunity for the clinical application of CDT. In the study, a universal nanoreactor (NR) consisting of liposome (Lip), tumor cell membrane (CM), and bis(2,4,5-trichloro-6-carboxyphenyl) oxalate (CPPO) is developed to tackle this challenge. The CPPO was first discovered to decompose under weak acidity and H2O2 conditions to generate carboxylic acids (R'COOH) and alcohols (R'OH) with reducibility, which will reduce M(n+1)+ to Mn+ and magnify the effect of CDT. Furthermore, glucose oxidase (GOx) was introduced to decompose glucose in tumor and generate H2O2 and glucose acid, which promote the degradation of CPPO, further strengthening the efficiency of CDT, leading to a butterfly effect. This demonstrated that the butterfly effect triggered by NR and GOx encourages Fenton/Fenton-like reactions of Fe3O4 and MoS2, thereby enhancing the tumor inhibition effect. The strategy of combining GOx and CPPO to strengthen the Fenton/Fenton-like reaction is a universal strategy, which provides a new and interesting perspective for CPPO in the application of CDT, reflecting the exquisite integration of Fenton chemistry and catalytic medicine.

Precise Regulation of Reactive Oxygen Species in Tumor Microenvironment for Alleviating Inhibitory Immunogenic Cell Death.

High level of C (ROS) within the tumor microenvironment (TME) not only damage tumor cells but also diminish the efficacy of immunogenic cell death (ICD) and the activity of tumor-infiltrating T lymphocytes, thereby limiting the effectiveness of immunotherapy. Therefore, precise modulation of ROS level is crucial to effectively eliminate tumor cells and activate ICD-induced immunotherapy. Here, an intelligent yolk shell nanoplatform (SPCCM) that features calcium carbonate shells capable of decomposing under acidic TME conditions, thereby releasing the natural antioxidant proanthocyanidins (PAs) and the photosensitizer Ce6 is designed. PAs scavenge ROS within tumors, extending the survival time of T lymphocytes, while Ce6, as an ICD inducer, generates high ROS concentrations upon laser irradiation, thus reaching the toxic threshold within tumor cells and inducing apoptosis. The resulting apoptotic cells serve as tumor-associated antigens, promoting dendritic cells (DCs) maturation, and activating ICD. By effectively neutralizing ROS in the TME, PAs sustainably reduce ROS level, thereby enhancing DCs activation and restoring antitumor immune cell activity suppressed by ROS (resulting in an eightfold increase in DCs activation). This study demonstrates effective synergistic effects between photodynamic therapy and immunotherapy by precisely modulating ROS level.

Flexocatalytic Reduction of Tumor Interstitial Fluid/Solid Pressure for Efficient Nanodrug Penetration.

The practical efficacy of nanomedicines for treating solid tumors is frequently low, predominantly due to the elevated interstitial pressure within such tumors that obstructs the penetration of nanomedicines. This increased interstitial pressure originates from both liquid and solid stresses related to an undeveloped vascular network and excessive fibroblast proliferation. To specifically resolve the penetration issues of nanomedicines for tumor treatment, this study introduces a holistic "dual-faceted" approach. A treatment platform predicated on the WS2/Pt Schottky heterojunction was adopted, and flexocatalysis technology was used to disintegrate tumor interstitial fluids, thus producing oxygen and reactive oxygen species and effectively mitigating the interstitial fluid pressure. The chemotherapeutic agent curcumin was incorporated to further suppress the activity of cancer-associated fibroblasts, minimize collagen deposition in the extracellular matrix, and alleviate solid stress. Nanomedicines achieve homologous targeting by enveloping the tumor cell membrane. It was found that this multidimensional strategy not only alleviated the high-pressure milieu of the tumor interstitium─which enhanced the efficiency of nanomedicine delivery─but also triggered tumor cell apoptosis via the generated reactive oxygen species and modulated the tumor microenvironment. This, in turn, amplified immune responses, substantially optimizing the therapeutic impacts of nanomedicines.

Nanomedicine alleviates doxorubicin-induced cardiotoxicity and enhances chemotherapy synergistic chemodynamic therapy.

Doxorubicin (DOX) is widely used in clinic as a broad-spectrum chemotherapy drug, which can enhance the efficacy of chemodynamic therapy (CDT) by interfering tumor-related metabolize to increase H2O2 content. However, DOX can induce serious cardiomyopathy (DIC) due to its oxidative stress in cardiomyocytes. Eliminating oxidative stress would create a significant opportunity for the clinical application of DOX combined with CDT. To address this issue, we introduced sodium ascorbate (AscNa), the main reason is that AscNa can be catalyzed to produce H2O2 by the abundant Fe3+ in the tumor site, thereby enhancing CDT. While the content of Fe3+ in heart tissue is relatively low, so the oxidation of AscNa had tumor specificity. Meanwhile, due to its inherent reducing properties, AscNa could also eliminate the oxidative stress generated by DOX, preventing cardiotoxicity. Due to the differences between myocardial tissue and tumor microenvironment, a novel nanomedicine was designed. MoS2 was employed as a carrier and CDT catalyst, loaded with DOX and AscNa, coating with homologous tumor cell membrane to construct an acid-responsive nanomedicine MoS2-DOX/AscNa@M (MDA@M). In tumor cells, AscNa enhances the synergistic therapy of DOX and MoS2. In cardiomyocytes, AscNa could effectively reduce the cardiomyopathy induced by DOX. Overall, this study enhanced the clinical potential of chemotherapy synergistic CDT.

Natural MOF-Like Photocatalytic Nanozymes Alleviate Tumor Pressure for Enhanced Nanodrug Penetration.

In oncological nanomedicine, overcoming the dual-phase high interstitial pressure in the tumor microenvironment is pivotal for enhancing the penetration and efficacy of nanotherapeutics. The elevated tumor interstitial solid pressure (TISP) is largely attributed to the overaccumulation of collagen in the extracellular matrix, while the increased tumor interstitial fluid pressure (TIFP) stems from the accumulation of fluid due to the aberrant vascular architecture. In this context, metal-organic frameworks (MOFs) with catalytic efficiency have shown potential in degrading tumor interstitial components, thereby reducing interstitial pressure. However, the potential biotoxicity of the organic components of MOFs limits their clinical translation. To circumvent this, a MOF-like photocatalytic nanozyme, RPC@M, using naturally derived cobalt phytate (CoPA) and resveratrol (Res) is developed. This nanozyme not only facilitates the decomposition of water in the tumor interstitium under photoactivation to reduce TIFP, but also generates an abundance of reactive oxygen species through its peroxidase-like activity to exert cytotoxic effects on tumor cells. Moreover, Res contributes to the reduction of collagen deposition, thereby lowering TISP. The concurrent diminution of both TISP and TIFP by RPC@M leads to enhanced tumor penetration and potent antitumor activity, presenting an innovative approach in constructing tumor therapeutic nanozymes from natural products.

Design of thin infrared quarter-wave and half-wave plates using antenna-array sheets.

A thin quarter-wave plate and a half-wave plate are designed based on multiple antenna-array sheets (AAS). For transmission through cascaded antenna-array sheets, an equivalent transmission-line model is used. The interspacing dielectric is modeled as a transmission line with each AAS treated as a loaded shunt admittance. By utilizing this transmission-line model to treat the plates as a differential phase shifter between two orthogonal polarizations, a quarter-wave plate can be designed with two AAS and a half-wave plate can be designed with three AAS. Both wave plates can achieve high transmission with the desired 90° and 180° phase difference between two orthogonal polarizations.

Nanomedicine-based multimodal therapies: Recent progress and perspectives in colon cancer.

Colon cancer has attracted much attention due to its annually increasing incidence. Conventional chemotherapeutic drugs are unsatisfactory in clinical application because of their lack of targeting and severe toxic side effects. In the past decade, nanomedicines with multimodal therapeutic strategies have shown potential for colon cancer because of their enhanced permeability and retention, high accumulation at tumor sites, co-loading with different drugs, and comb-ination of various therapies. This review summarizes the advances in research on various nanomedicine-based therapeutic strategies including chemotherapy, radiotherapy, phototherapy (photothermal therapy and photodynamic therapy), chemodynamic therapy, gas therapy, and immunotherapy. Additionally, the therapeutic mechanisms, limitations, improvements, and future of the above therapies are discussed.

Cascaded Antitumor Therapy Excited by Dual Nanozymes Based on Energy Restriction and Photocatalysis.

In nanocatalytic medicine, drugs can be transformed into toxic components through highly selective and highly specific catalytic reactions in the tumor microenvironment, avoiding toxic side effects on normal tissues. Due to the coexistence of Ce3+ and Ce4+, CeO2 is endowed with dual nanozyme activities. Herein, CeO2 nanoparticles served as templates to construct a biomimetic nanodrug delivery system (C/CeO2@M) by electrostatic adsorption of carbon quantum dots (CQDs) and coating a homologous tumor cytomembrane. After homologous targeting to tumors, the CQDs emitted 350-600 nm light under 660 nm laser irradiation by upconversion luminescence, which caused a CeO2-mediated photocatalytic reaction to generate reactive oxygen species. The catalase-like activity of CeO2-enabled converting excess H2O2 to O2, which not only alleviated tumor hypoxia and promoted intratumor drug delivery but also provided substrates for subsequent catalytic reactions. Meanwhile, the phosphatase activity of CeO2 could consume adenosine triphosphate (ATP) to block the energy supply for tumor cells, thus limiting cell proliferation and metastasis. The strategy of energy restriction and photocatalysis of dual nanozyme stimulation offers great potentials in enhancing drug penetration and eradicating solid tumors.

Decrease in Tumor Interstitial Pressure for Enhanced Drug Intratumoral Delivery and Synergistic Tumor Therapy.

Currently, one of the main reasons for the ineffectiveness of tumor treatment is that the abnormally high tumor interstitial pressure (TIP) hinders the delivery of drugs to the tumor center and promotes intratumoral cell survival and metastasis. Herein, we designed a "nanomotor" by in situ growth of Ag2S nanoparticles on the surface of ultrathin WS2 to fabricate Z-scheme photocatalytic drug AWS@M, which could rapidly enter tumors by splitting water in interstitial liquid to reduce TIP, along with O2 generation. Moreover, the O2 would be further converted to reactive oxygen species (ROS), accompanied by increased local temperature of tumors, and the combination of ROS with thermotherapy could eliminate the deep tumor cells. Therefore, the "nanomotor'' could effectively reduce the TIP levels of cervical cancer and pancreatic cancer (degradation rates of 40.2% and 36.1%, respectively) under 660 nm laser irradiation, further enhance intratumor drug delivery, and inhibit tumor growth (inhibition ratio 95.83% and 87.61%, respectively), and the related mechanism in vivo was explored. This work achieves efficiently photocatalytic water-splitting in tumor interstitial fluid to reduce TIP by the nanomotor, which addresses the bottleneck problem of blocking of intratumor drug delivery, and provides a general strategy for effectively inhibiting tumor growth.

MoS2 nanoflower-mediated enhanced intratumoral penetration and piezoelectric catalytic therapy.

The absence of lymphatic vessels in tumors leads to the retention of interstitial fluid, and the formation of an inverse pressure difference between the tumor and blood vessels hinders drug delivery deep into the tumor, which leads to tumor recurrence and metastasis. Therefore, we designed a novel strategy to downregulate tumor interstitial fluid pressure (TIFP) by water splitting in the tumor interstitium based on piezoelectric catalysis nanomedicine. First, the chemotherapeutic drug doxorubicin (DOX) was loaded on the piezoelectric catalytic material MoS2 and then encapsulated with tumor cell membrane (CM) to obtain MD@C. MD@C could not only target the tumor through homologous targeting but, more importantly, also triggered piezoelectric catalytic water splitting under ultrasound (US) stimulation; as a result, the TIFPs of U14 and PAN02 tumor-bearing mice were reduced to 57.14% and 45.5%, respectively, and the tumor inhibition rates of MD@C were 96.75% and 99.21%, which increased the perfusion of blood-derived drugs in the tumors. Moreover, the hydroxyl radicals generated by piezoelectric catalysis could effectively inhibit the growth of tumors in combination with DOX. Consequently, the piezoelectric catalytic water splitting strategy of MD@C can enhance drug delivery, providing a new universal platform for the treatment of solid malignant tumors.

Diagnostic and therapeutic nanoenzymes for enhanced chemotherapy and photodynamic therapy.

Nanozymes, as a kind of artificial mimic enzymes, have superior catalytic capacity and stability. As lack of O2 in tumor cells can cause resistance to drugs, we designed drug delivery liposomes (MnO2-PTX/Ce6@lips) loaded with catalase-like nanozymes of manganese dioxide nanoparticles (MnO2 NPs), paclitaxel (PTX) and chlorin e6 (Ce6) to consume tumor's native H2O2 and produce O2. Based on the catalysis of MnO2 NPs, a large amount of oxygen was produced by MnO2-PTX/Ce6@lips to burst the liposomes and achieve a responsive release of the loaded drug (paclitaxel), and the released O2 relieved the chemoresistance of tumor cells and provided raw materials for photodynamic therapy. Subsequently, MnO2 NPs were decomposed into Mn2+ in an acidic tumor environment to be used as contrast agents for magnetic resonance imaging. The MnO2-PTX/Ce6@lips enhanced the efficacy of chemotherapy and photodynamic therapy (PDT) in bearing-tumor mice, even achieving complete cure. These results indicated the great potential of MnO2-PTX/Ce6@lips for the modulation of the TME and the enhancement of chemotherapy and PDT along with MRI tracing in the treatment of tumors.