A core-shell Au@Cu2-xSe heterogeneous metal nanocomposite for photoacoustic and computed tomography dual-imaging-guided photothermal boosted chemodynamic therapy

Ultrasound-Based Micro-/Nanosystems for Biomedical Applications

Due to the intrinsic non-invasive nature, cost-effectiveness, high safety, and real-time capabilities, besides diagnostic imaging, ultrasound as a typical mechanical wave has been extensively developed as a physical tool for versatile biomedical applications. Especially, the prosperity of nanotechnology and nanomedicine invigorates the landscape of ultrasound-based medicine. The unprecedented surge in research enthusiasm and dedicated efforts have led to a mass of multifunctional micro-/nanosystems being applied in ultrasound biomedicine, facilitating precise diagnosis, effective treatment, and personalized theranostics. The effective deployment of versatile ultrasound-based micro-/nanosystems in biomedical applications is rooted in a profound understanding of the relationship among composition, structure, property, bioactivity, application, and performance. In this comprehensive review, we elaborate on the general principles regarding the design, synthesis, functionalization, and optimization of ultrasound-based micro-/nanosystems for abundant biomedical applications. In particular, recent advancements in ultrasound-based micro-/nanosystems for diagnostic imaging are meticulously summarized. Furthermore, we systematically elucidate state-of-the-art studies concerning recent progress in ultrasound-based micro-/nanosystems for therapeutic applications targeting various pathological abnormalities including cancer, bacterial infection, brain diseases, cardiovascular diseases, and metabolic diseases. Finally, we conclude and provide an outlook on this research field with an in-depth discussion of the challenges faced and future developments for further extensive clinical translation and application.

The Advancing Role of Nanocomposites in Cancer Diagnosis and Treatment

The relentless pursuit of effective cancer diagnosis and treatment strategies has led to the rapidly expanding field of nanotechnology, with a specific focus on nanocomposites. Nanocomposites, a combination of nanomaterials with diverse properties, have emerged as versatile tools in oncology, offering multifunctional platforms for targeted delivery, imaging, and therapeutic interventions. Nanocomposites exhibit great potential for early detection and accurate imaging in cancer diagnosis. Integrating various imaging modalities, such as magnetic resonance imaging (MRI), computed tomography (CT), and fluorescence imaging, into nanocomposites enables the development of contrast agents with enhanced sensitivity and specificity. Moreover, functionalizing nanocomposites with targeting ligands ensures selective accumulation in tumor tissues, facilitating precise imaging and diagnostic accuracy. On the therapeutic front, nanocomposites have revolutionized cancer treatment by overcoming traditional challenges associated with drug delivery. The controlled release of therapeutic agents from nanocomposite carriers enhances drug bioavailability, reduces systemic toxicity, and improves overall treatment efficacy. Additionally, the integration of stimuli-responsive components within nanocomposites enables site-specific drug release triggered by the unique microenvironment of the tumor. Despite the remarkable progress in the field, challenges such as biocompatibility, scalability, and long-term safety profiles remain. This article provides a comprehensive overview of recent developments, challenges, and prospects, emphasizing the transformative potential of nanocomposites in revolutionizing the landscape of cancer diagnostics and therapeutics. In Conclusion, integrating nanocomposites in cancer diagnosis and treatment heralds a new era for precision medicine.

Janus ACSP Nanoparticle for Synergistic Chemodynamic Therapy and Radiosensitization

Protective autophagy and DNA damage repair lead to tumor radio-resistance. Some hypoxic tumors exhibit a low radiation energy absorption coefficient in radiation therapy. High doses of X-rays may lead to side effects in the surrounding normal tissues. In order to overcome the radio-resistance and improve the efficacy of radiotherapy based on the characteristics of the tumor microenvironment, the development of radiosensitizers has attracted much attention. In this study, a Janus ACSP nanoparticle (NP) was developed for chemodynamic therapy and radiosensitization. The reactive oxygen species generated by the Fenton-like reaction regulated the distribution of cell cycles from a radioresistant phase to a radio-sensitive phase. The high-Z element, Au, enhanced the production of hydroxyl radicals (•OH) under X-ray radiation, promoting DNA damage and cell apoptosis. The NP delayed DNA damage repair by interfering with certain proteins involved in the DNA repair signaling pathway. In vivo experiments demonstrated that the combination of the copper-ion-based Fenton-like reaction and low-dose X-ray radiation enhanced the effectiveness of radiotherapy, providing a novel approach for synergistic chemodynamic and radiosensitization therapy. This study provides valuable insights and strategies for the development and application of NPs in cancer treatment.

Rapid Synthesis of Trimetallic Nanozyme for Sustainable Cascaded Catalytic Therapy via Tumor Microenvironment Remodulation

Tumor microenvironment (TME)-responsive nanozyme-catalyzed cancer therapy shows great potential due to its specificity and efficiency. However, breaking the self-adaption of tumors and improving the sustainable remodeling TME ability remains a major challenge for developing novel nanozymes. Here, a rapid method is developed first to synthesize unprecedented trimetalic nanozyme (AuMnCu, AMC) with a targeting peptide (AMCc), which exhibits excellent peroxidase-like, catalase-like, and glucose oxidase-like activities. The released Cu and Mn ions in TME consume endogenous H2 O2 and produce O2 , while the AMCccatalyzes glucose oxidation reaction to generate H2 O2 and gluconic acid, which achieves the starvation therapy by depleting the energy and enhances the chemodynamic therapy effect by lowering the pH of the TME and producing extra H2 O2 . Meanwhile, the reactive oxygen species damage is amplified, as AMCc can constantly oxidize intracellular reductive glutathione through the cyclic valence alternation of Cu and Mn ions, and the generated Cu+ elevate the production of ·OH from H2 O2 . Further studies depict that the well-designed AMCc exhibits the excellent photothermal performance and achieves TME-responsive sustainable starvation/photothermal-enhanced chemodynamic synergistic effects in vitro and in vivo. Overall, a promising approach is demonstrated here to design "all-in-one" nanozyme for theranostics by remodeling the TME.

TRAIL-driven targeting and reversing cervical cancer radioresistance by seleno-nanotherapeutics through regulating cell metabolism

Recently, radioresistance has become a major obstacle in the radiotherapy of cervical cancer. To demonstrate enhanced radiosensitization against radioresistant cervical cancer, radioresistant cervical cancer cell line was developed and the mechanism of radioresistance was explored. Due to the overexpression of (death receptor 5, DR5) in cervical cancer, tumor necrosis factor-related apoptosis-inducing ligand (TRAIL)-overexpressed cervical cancer cell membrane-camouflaged Cu2-xSe nanomedicine (CCMT) was designed. Since the CCMT was encapsulated with TRAIL-modified cell membrane, it represented high target to cervical cancer cell and immune evasion. Furthermore, Cu2-xSe had the ability to scavenge glutathione (GSH) and produce ·OH with excess H2O2 in the tumor microenvironment. The presence of CCMT combined with radiation therapy could effectively increase the 1O2 produced by X-rays. In vitro and in vivo studies elaborated that CCMT exhibited excellent radiosensitization properties to reverse radiotolerance by scavenging GSH and promoting DNA damage, apoptosis, mitochondrial membrane potential damage and metabolic disruption. Collectively, this study suggested that the development of TRAIL-overexpressed cell membrane-camouflaged Cu2-xSe nanomedicine could advance future cervical cancer treatment and minimize the disadvantages associated with radiation treatment.

Cytotoxicity of AuCu-Cu2S Nanocomposites: Implications for Biological Evaluation of the Nanocomposite Effect on Bombyx mori Silkworms and Cell Lines

AuCu-Cu2S nanocomposites are unique materials with exceptional properties that have recently received a lot of interest. However, little is known about their potential toxicity in terrestrial organisms and their subsequent effects on the environment. Therefore, it is essential to develop effective methodologies for evaluating AuCu-Cu2S nanocomposites in biological systems. This study reports the biological evaluation of the AuCu-Cu2S nanocomposite from animal and cell entity levels. The Bombyx mori silkworm was used as a model organism to study the effects of different concentrations of AuCu-Cu2S on silkworm development. Transcriptome analysis was also carried out to examine the genetic modulation exerted by the treatment. Moreover, biocompatibility and cytotoxicity of AuCu-Cu2S were evaluated in human bronchial epithelial cells 16HBE, human lung adenocarcinoma, and the insect Spodoptera frugiperda cell sf9 cell lines. The results showed that although AuCu-Cu2S at ≤400 ppm can prolong the eating habit of silkworms and promote the weight of the cocoon layer, there was an increase in silkworm mortality and a decrease in moth formation at a concentration of ≥800 ppm. The genetic regulation by AuCu-Cu2S treatment showed varying effects in the silkworm, primarily related to functions such as transport and catabolism, metabolism of cofactors and vitamins, xenobiotic biodegradation, amino acid, and carbohydrate. 16HBE, PC-9, and sf9 treated with 300 ppm of AuCu-Cu2S showed viability percentages of 60, 20, and 90%, respectively. Thus, AuCu-Cu2S at low concentrations serves as a safe and biocompatible material for the sf9 cell lines but is lethal to 16HBE and PC-9. This research could aid in understanding the biological effects and biocompatibility of AuCu-Cu2S nanocomposites, particularly in the field of biochemistry; however, the mechanisms involved need further exploration.

Advancements in the Application of the Fenton Reaction in the Cancer Microenvironment

Cancer is a complex and multifaceted disease that continues to be a global health challenge. It exerts a tremendous burden on individuals, families, healthcare systems, and society as a whole. To mitigate the impact of cancer, concerted efforts and collaboration on a global scale are essential. This includes strengthening preventive measures, promoting early detection, and advancing effective treatment strategies. In the field of cancer treatment, researchers and clinicians are constantly seeking new approaches and technologies to improve therapeutic outcomes and minimize adverse effects. One promising avenue of investigation is the utilization of the Fenton reaction, a chemical process that involves the generation of highly reactive hydroxyl radicals (·OH) through the interaction of hydrogen peroxide (H2O2) with ferrous ions (Fe2+). The generated ·OH radicals possess strong oxidative properties, which can lead to the selective destruction of cancer cells. In recent years, researchers have successfully introduced the Fenton reaction into the cancer microenvironment through the application of nanotechnology, such as polymer nanoparticles and light-responsive nanoparticles. This article reviews the progress of the application of the Fenton reaction, catalyzed by polymer nanoparticles and light-responsive nanoparticles, in the cancer microenvironment, as well as the potential applications and future development directions of the Fenton reaction in the field of tumor treatment.

Smart Chemical Oxidative Polymerization Strategy To Construct Au@PPy Core-Shell Nanoparticles for Cancer Diagnosis and Imaging-Guided Photothermal Therapy

Imaging-guided photothermal therapy (PTT) in a single nanoscale platform has aroused extensive research interest in precision medicine, yet only a few methods have gained wide acceptance. Thus, it remained an urgent need to facilely develop biocompatible and green probes with excellent theranostic capacity for superior biomedical applications. In this study, a smart chemical oxidative polymerization strategy was successfully developed for the synthesis of Au@PPy core-shell nanoparticles with polyvinyl alcohol (PVA) as the hydrophile. In the reaction, the reactant tetrachloroauric acid (HAuCl₄) was reduced by pyrrole to fabricate a gold (Au) core, and pyrrole was oxidized to deposit around the Au core to form a polypyrrole (PPy) shell. The as-synthesized Au@PPy nanoparticles showed a regular core-shell morphology and good colloidal stability. Relying on the high X-ray attenuation of Au and strong near-infrared (NIR) absorbance of PPy and Au, Au@PPy nanoparticles exhibited excellent performance in blood pool/tumor imaging and PTT treatment by a series of in vivo experiments, in which tumor could be precisely positioned and thoroughly eradicated. Hence, the facile chemical oxidative polymerization strategy for constructing monodisperse Au@PPy core-shell nanoparticles with potential for cancer diagnosis and imaging-guided photothermal therapy shed light on an innovative design concept for the facile fabrication of biomedical materials.

Targeted-detection and sequential-treatment of small hepatocellular carcinoma in the complex liver environment by GPC-3-targeted nanoparticles

Despite advancements in diagnostic methods and therapeutic strategies, the mortality rate of hepatocellular carcinoma (HCC) remains as high as its incidence rate. Most liver cancers are detected in the advanced stages, when treatment options are limited. Small HCC is difficult to diagnose and is often overlooked by current imaging methods because of the complexity of the liver environment, especially in cirrhotic livers. In the present study, we developed a tumor "cruise missile", mesoporous Fe₃O₄-containing glucose oxidase-conjugated GPC3 peptide nanoparticles (FGP NPs). It was designed to enhance the accuracy of small HCC visualization to 85.7% using combined ultrasound/photoacoustic imaging in complex liver environment, which facilitated sequential catalytic targeted therapy for small HCC. In a carcinogen-induced mouse HCC model, FGP NPs could be used to accurately diagnose HCC in a liver cirrhosis background as well as distinguish HCC nodules from other abnormal liver nodules, such as cirrhosis nodules and necrotic nodules, by dynamic contrast-enhanced photoacoustic imaging. In a mouse xenograft HCC model, highly reactive oxygen species were formed by sequential catalytic reactions, which promoted HCC cell apoptosis, significantly increasing the survival of the model mice. The present study provides a basis for the precise detection and elimination of small HCCs in the complex liver environment.

Nanozymes-recent development and biomedical applications

Nanozyme is a series of nanomaterials with enzyme-mimetic activities that can proceed with the catalytic reactions of natural enzymes. In the field of biomedicine, nanozymes are capturing tremendous attention due to their high stability and low cost. Enzyme-mimetic activities of nanozymes can be regulated by multiple factors, such as the chemical state of metal ion, pH, hydrogen peroxide (H₂O₂), and glutathione (GSH) level, presenting great promise for biomedical applications. Over the past decade, multi-functional nanozymes have been developed for various biomedical applications. To promote the understandings of nanozymes and the development of novel and multifunctional nanozymes, we herein provide a comprehensive review of the nanozymes and their applications in the biomedical field. Nanozymes with versatile enzyme-like properties are briefly overviewed, and their mechanism and application are discussed to provide understandings for future research. Finally, underlying challenges and prospects of nanozymes in the biomedical frontier are discussed in this review.

Recent Advances in Single Fe-Based Nanoagents for Photothermal-Chemodynamic Cancer Therapy

Monomodal cancer therapies are often unsatisfactory, leading to suboptimal treatment effects that result in either an inability to stop growth and metastasis or prevent relapse. Thus, synergistic strategies that combine different therapeutic modalities to improve performance have become the new research trend. In this regard, the integration of photothermal therapy (PTT) with chemodynamic therapy (CDT), especially PTT/CDT in the second near-infrared (NIR-II) biowindow, has been demonstrated to be a highly efficient and relatively safe concept. With the rapid development of nanotechnology, nanoparticles can be designed from specific elements, such as Fe, that are equipped with both PTT and CDT therapeutic functions. In this review, we provide an update on the recent advances in Fe-based nanoplatforms for combined PTT/CDT. The perspectives on further improvement of the curative efficiency are described, highlighting the important scientific obstacles that require resolution in order to reach greater heights of clinical success. We hope this review will inspire the interest of researchers in developing novel Fe-based nanomedicines for multifunctional theranostics.