A GSH-Gated DNA Nanodevice for Tumor-Specific Signal Amplification of microRNA and MR Imaging-Guided Theranostics

A cancer-targeted glutathione-gated probe for self-sufficient ST/CDT combination therapy and FRET-based miRNA imaging

A cancer-targeted glutathione (GSH)-gated theranostic probe (CGT probe) for intracellular miRNA imaging and combined treatment of self-sufficient starvation therapy (ST) and chemodynamic therapy (CDT) was developed. The CGT probe is constructed using MnO2 nanosheet (MS) as carrier material to adsorb the elaborately designed functional DNAs. It can be internalized by cancer cells via specific recognition between the AS1411 aptamer and nucleolin. After CGT probe entering the cancer cells, the overexpressed GSH, as gate-control, can degrade MS to Mn2+ which can be used for CDT by Fenton-like reaction. Simultaneously, Mn2+-mediated CDT can further cascade with the enzyme-like activities (catalase-like activity and glucose oxidase-like activity) of CGT probe, achieving self-sufficient ST/CDT synergistic therapy. Meanwhile, the anchored DNAs are released, achieving in situ signal amplification via disubstituted-catalytic hairpin assembly (DCHA) and FRET (fluorescence resonance energy transfer) imaging of miR-21. The in vitro and in vivo experiments demonstrated that accurate and sensitive miRNA detection can be achieved using the CGT probe. Overall, the ingenious CGT probe opens a new avenue for the development of early clinical diagnosis and cancer therapy.

Spatiotemporally controlled Pseudomonas exotoxin transgene system combined with multifunctional nanoparticles for breast cancer antimetastatic therapy

The tumor microenvironment is a barrier to breast cancer therapy. Cancer-associated fibroblast cells (CAFs) can support tumor proliferation, metastasis, and drug resistance by secreting various cytokines and growth factors. Abnormal angiogenesis provides sufficient nutrients for tumor proliferation. Considering that CAFs express the sigma receptor (which recognizes anisamide, AA), we developed a CAFs and breast cancer cells dual-targeting nano drug delivery system to transport the LightOn gene express system, a spatiotemporal controlled gene expression consisting of a light-sensitive transcription factor and a specific minimal promoter. We adopted RGD (Arg-Gly-Asp) to selectively bind to the αvβ3 integrin on activated vascular endothelial cells and tumor cells. After the LightOn system has reached the tumor site, LightOn gene express system can spatiotemporal controllably express toxic Pseudomonas exotoxin An under blue light irradiation. The LightOn gene express system, combined with multifunctional nanoparticles, achieved high targeting delivery efficiency both in vitro and in vivo. It also displayed strong tumor and CAFs inhibition, anti-angiogenesis ability and anti-metastasis ability, with good safety. Moreover, it improved survival rate, survival time, and lung metastasis rate in a mouse breast cancer model. This study proves the efficacy of combining the LightOn system with targeted multifunctional nanoparticles in tumor and anti-metastatic therapy and provides new insights into tumor microenvironment regulation.

High-fidelity intracellular imaging of multiple miRNAs via stimulus-responsive nanocarriers and catalytic hairpin assembly

An advanced nanoplatform was developed by integrating catalytic hairpin assembly (CHA) with glutathione-responsive nanocarriers, enabling superior imaging of dual cancer-related miRNAs. Two distinct CHA circuits for the sensing of miRNA-21 and miRNA-155 were functionalized on biodegraded MnO2. In the presence of GSH and the corresponding miRNAs, the degraded MnO2 released the DNA cargos, activating the CHA circuits and recovering the fluorescence. This approach offers a reliable sensing performance with highly selective cell-identification capacity, positioning it as a pivotal tool for imaging multiple biomarkers in living cells.

Mn2+/CpG Oligodeoxynucleotides Codecorated Black Phosphorus Nanosheet Platform for Enhanced Antitumor Potency in Multimodal Therapy

Manganese ions (Mn2+)-coordinated nanoparticles have emerged as a promising class of antitumor nanotherapeutics, capable of simultaneously disrupting the immunosuppressive tumor microenvironment (TME) and triggering the stimulator of interferon genes (STING) pathway-dependent antitumor immunity. However, the activation of STING signaling by Mn2+-based monotherapies is suboptimal for comprehensive stimulation of antigen presenting cells and reversal of immunosuppression in the TME. Here, we report the design of a Mn2+/CpG oligodeoxynucleotides (ODNs) codecorated black phosphorus nanosheet (BPNS@Mn2+/CpG) platform based on the Mn2+ modification of BPNS and subsequent adsorption of synthetic CpG ODNs. The coordination of Mn2+ significantly improved the stability of BPNS and the adsorption of CpG ODNs. The acidic TME and endosomal compartments can disrupt the Mn2+ coordination, triggering pH-responsive release of CpG ODNs and Mn2+ to effectively activate the Toll-like receptor 9 and STING pathways. As a result, M2-type macrophages and immature dendritic cells were strongly stimulated in the TME, thereby increasing T lymphocyte infiltration and reversing the immunosuppression within the TME. Phototherapy and chemodynamic therapy, utilizing the BPNS@Mn2+/CpG platform, have demonstrated efficacy in inducing immunogenic cell death upon 808 nm laser irradiation. Importantly, the treatment of BPNS@Mn2+/CpG with laser irradiation exhibited significant therapeutic efficacy against the irradiated primary tumor and effectively suppressed the growth of nonirradiated distant tumor. Moreover, it induced a robust immune memory, providing long-lasting protection against tumor recurrence. This study demonstrated the enhanced antitumor potency of BPNS@Mn2+/CpG in multimodal therapy, and its proof-of-concept application as a metal ion-modified BPNS material for effective DNA/drug delivery and immunotherapy.

Computational model of radiation oxygen effect with Monte Carlo simulation: effects of antioxidants and peroxyl radicals

PURPOSE

Oxygen plays a crucial role in radiation biology. Antioxidants and peroxyl radicals affect the oxygen effect greatly. This study aims to establish a computational model of the oxygen effect and explore the effect attributed to antioxidants and peroxyl radicals.

MATERIALS AND METHODS

Oxygen-related reactions are added to our track-structure Monte Carlo code NASIC, including oxygen fixation, chemical repair by antioxidants and damage migration from base-derived peroxyl radicals. Then the code is used to simulate the DNA damage under various oxygen, antioxidant and damage migration rate conditions. The oxygen enhancement ratio(OER) is calculated quantifying by the number of double-strand breaks for each condition. The roles of antioxidants and peroxyl radicals are examined by manipulating the relevant parameters.

RESULTS AND CONCLUSIONS

Our results indicate that antioxidants are capable of rapidly restoring DNA radicals through chemical reactions, which compete with natural and oxygen fixation processes. Additionally, antioxidants can react with peroxyl radicals derived from bases, thereby preventing the damage from migrating to DNA strands. By quantitatively accounting for the impact of peroxyl radicals and antioxidants on the OER curves, our study establishes a more precise and comprehensive model of the radiation oxygen effect.

Cascade strategy for glucose oxidase-based synergistic cancer therapy using nanomaterials

Nanomaterial-based cancer therapy faces significant limitations due to the complex nature of the tumor microenvironment (TME). Starvation therapy is an emerging therapeutic approach that targets tumor cell metabolism using glucose oxidase (GOx). Importantly, it can provide a material or environmental foundation for other diverse therapeutic methods by manipulating the properties of the TME, such as acidity, hydrogen peroxide (H2O2) levels, and hypoxia degree. In recent years, this cascade strategy has been extensively applied in nanoplatforms for ongoing synergetic therapy and still holds undeniable potential. However, only a few review articles comprehensively elucidate the rational designs of nanoplatforms for synergetic therapeutic regimens revolving around the conception of the cascade strategy. Therefore, this review focuses on innovative cascade strategies for GOx-based synergetic therapy from representative paradigms to state-of-the-art reports to provide an instructive, comprehensive, and insightful reference for readers. Thereafter, we discuss the remaining challenges and offer a critical perspective on the further advancement of GOx-facilitated cancer treatment toward clinical translation.

Advancements in Nanogels for Enhanced Ocular Drug Delivery: Cutting-Edge Strategies to Overcome Eye Barriers

Nanomedicine in gel or particle formation holds considerable potential for enhancing passive and active targeting within ocular drug delivery systems. The complex barriers of the eye, exemplified by the intricate network of closely connected tissue structures, pose significant challenges for drug administration. Leveraging the capability of engineered nanomedicine offers a promising approach to enhance drug penetration, particularly through active targeting agents such as protein peptides and aptamers, which facilitate targeted release and heightened bioavailability. Simultaneously, DNA carriers have emerged as a cutting-edge class of active-targeting structures, connecting active targeting agents and illustrating their potential in ocular drug delivery applications. This review aims to consolidate recent findings regarding the optimization of various nanoparticles, i.e., hydrogel-based systems, incorporating both passive and active targeting agents for ocular drug delivery, thereby identifying novel mechanisms and strategies. Furthermore, the review delves into the potential application of DNA nanostructures, exploring their role in the development of targeted drug delivery approaches within the field of ocular therapy.

Degradable iron-rich mesoporous dopamine as a dual-glutathione depletion nanoplatform for photothermal-enhanced ferroptosis and chemodynamic therapy

Glutathione (GSH) is a crucial factor in limiting the effects of chemodynamic therapy (CDT) and ferroptosis, an iron-based cell death pathway. Based on this, we constructed iron-rich mesoporous dopamine (MPDA@Fe) nanovehicles with a dual-GSH depletion function by combining MPDA and Fe. Poly (ethylene glycol) (PEG) was further modified to provide desirable stability (PM@Fe) and glucose oxidase (GOx) was grafted onto PM@Fe (GPM@Fe) to address the limitation of hydrogen peroxide (H₂O₂). After the nanoparticles reached the tumor site, the weakly acidic microenvironment promoted the release of Fe. Then Fe^II reacted with H₂O₂ to generate hydroxyl radical (OH) and Fe^III. The generated Fe^III was reduced to Fe^II by GSH, which circularly participated in the Fenton reaction and continuously produced tumor inhibitory free radicals. Meanwhile, GOx consumed glucose to provide H₂O₂ for the reaction. MPDA had also been reported to deplete GSH. Therefore, dual consumption of GSH led to the destruction of intracellular redox balance and inhibition of glutathione-dependent peroxidase 4 (GPX4) expression, resulting in an increase in lipid peroxides (LPO) and further induction of ferroptosis. Additionally, MPDA-mediated photothermal therapy (PTT) raised the temperature of tumor area and produced photothermal-enhanced cascade effects. Hence, the synergistic strategy that combined dual-GSH depletion-induced ferroptosis, enhanced CDT and photothermal cascade enhancement based on MPDA@Fe could provide more directions for designing nanomedicines for cancer treatment.

Orthometric multicolor encoded hybridization chain reaction amplifiers for multiplexed microRNA profiling in living cells

Multiplexed microRNA (miRNA) profiling of more than four types in living cells is challenging due to fluorescent spectral overlap, representing a significant limitation in studying the complex interactions related to the occurrence and development of diseases. Herein, we report a multiplexed fluorescent imaging strategy based on an orthometric multicolor encoded hybridization chain reaction amplifier named multi-HCR. The targeting miRNA can trigger this multi-HCR strategy due to the specific sequence recognition, and then its self-assembly to amplify the programmability signals. We take the four-colored chain amplifiers, showing that the multi-HCR can form 15 combinations simultaneously. In a living process of hypoxia-induced apoptosis and autophagy under complicated mitochondria and endoplasmic reticulum stress, the multi-HCR demonstrates excellent performance in detecting eight different miRNA changes. The multi-HCR provides a robust strategy for simultaneously profiling multiplexed miRNA biomarkers in studying complicated cellular processes.

A hybrid nanopharmaceutical for specific-amplifying oxidative stress to initiate a cascade of catalytic therapy for pancreatic cancer

BACKGROUND

Oxidative stress (OS) induced by an imbalance of oxidants and antioxidants is an important aspect in anticancer therapy, however, as an adaptive response, excessive glutathione (GSH) in the tumor microenvironment (TME) acts as an antioxidant against high reactive oxygen species (ROS) levels and prevents OS damage to maintain redox homoeostasis, suppressing the clinical efficacy of OS-induced anticancer therapies.

RESULTS

A naturally occurring ROS-activating drug, galangin (GAL), is introduced into a Fenton-like catalyst (SiO₂@MnO₂) to form a TME stimulus-responsive hybrid nanopharmaceutical (SiO₂-GAL@MnO₂, denoted SG@M) for enhancing oxidative stress. Once exposed to TME, as MnO₂ responds and consumes GSH, the released Mn²⁺ converts endogenous hydrogen peroxide (H₂O₂) into hydroxyl radicals (·OH), which together with the subsequent release of GAL from SiO₂ increases ROS. The "overwhelming" ROS cause OS-mediated mitochondrial malfunction with a decrease in mitochondrial membrane potential (MMP), which releases cytochrome c from mitochondria, activates the Caspase 9/Caspase 3 apoptotic cascade pathway. Downregulation of JAK2 and STAT3 phosphorylation levels blocks the JAK2/STAT3 cell proliferation pathway, whereas downregulation of Cyclin B1 protein levels arrest the cell cycle in the G2/M phase. During 18 days of in vivo treatment observation, tumor growth inhibition was found to be 62.7%, inhibiting the progression of pancreatic cancer. Additionally, the O₂ and Mn²⁺ released during this cascade catalytic effect improve ultrasound imaging (USI) and magnetic resonance imaging (MRI), respectively.

CONCLUSION

This hybrid nanopharmaceutical based on oxidative stress amplification provides a strategy for multifunctional integrated therapy of malignant tumors and image-visualized pharmaceutical delivery.

Nucleic Acid Probes in Bio-Imaging and Diagnostics: Recent Advances in ODN-Based Fluorescent and Surface-Enhanced Raman Scattering Nanoparticle and Nanostructured Systems

Raman nanoparticle probes are a potent class of optical labels for the interrogation of pathological and physiological processes in cells, bioassays, and tissues. Herein, we review the recent advancements in fluorescent and Raman imaging using oligodeoxyribonucleotide (ODN)-based nanoparticles and nanostructures, which show promise as effective tools for live-cell analysis. These nanodevices can be used to investigate a vast number of biological processes occurring at various levels, starting from those involving organelles, cells, tissues, and whole living organisms. ODN-based fluorescent and Raman probes have contributed to the achievement of significant advancements in the comprehension of the role played by specific analytes in pathological processes and have inaugurated new possibilities for diagnosing health conditions. The technological implications that have emerged from the studies herein described could open new avenues for innovative diagnostics aimed at identifying socially relevant diseases like cancer through the utilization of intracellular markers and/or guide surgical procedures based on fluorescent or Raman imaging. Particularly complex probe structures have been developed within the past five years, creating a versatile toolbox for live-cell analysis, with each tool possessing its own strengths and limitations for specific studies. Analyzing the literature reports in the field, we predict that the development of ODN-based fluorescent and Raman probes will continue in the near future, disclosing novel ideas on their application in therapeutic and diagnostic strategies.

Activatable dual-functional molecular agents for imaging-guided cancer therapy

Theranostics has attracted great attention due to its ability to combine the real-time diagnosis of cancers with efficient treatment modalities. Activatable dual-functional molecular agents could be synthesized by covalently conjugating imaging agents, therapeutic agents, stimuli-responsive linkers and/or targeting molecules together. They could be selectively activated by overexpressed physiological stimuli or external triggers at the tumor sites to release imaging agents and cytotoxic drugs, thus offering many advantages for tumor imaging and therapy, such as a high signal-to-noise ratio, low systemic toxicity, and improved therapeutic effects. This review summarizes the recent advances of dual-functional molecular agents that respond to various physiological or external stimuli for cancer theranostics. The molecular designs, synthetic strategies, activatable mechanisms, and biomedical applications of these molecular agents are elaborated, followed by a brief discussion of the challenges and opportunities in this field.

Synergistic Reinforcing of Immunogenic Cell Death and Transforming Tumor-Associated Macrophages Via a Multifunctional Cascade Bioreactor for Optimizing Cancer Immunotherapy

Immunogenic cell death (ICD) has aroused widespread attention because it can reconstruct a tumor microenvironment and activate antitumor immunity. This study proposes a two-way enhancement of ICD based on a CaO₂ @CuS-MnO₂ @HA (CCMH) nanocomposite to overcome the insufficient damage-associated molecular patterns (DAMPs) of conventional ICD-inducers. The near-infrared (NIR) irradiation (1064 nm) of CuS nanoparticles generates ¹ O₂ through photodynamic therapy (PDT) to trigger ICD, and it also damages the Ca²⁺ buffer function of mitochondria. Additionally, CaO₂ nanoparticles react with H₂ O to produce a large amount of O₂ and Ca²⁺ , which respectively lead to enhanced PDT and Ca²⁺ overload during mitochondrial damage, thereby triggering a robust ICD activation. Moreover, oxidative-damaged mitochondrial DNA, induced by PDT and released from tumor cells, reprograms the immunosuppressive tumor microenvironment by transforming tumor-associated macrophages to the M1 subphenotype. This study shows that CCMH with NIR-II irradiation can elicit adequate DAMPs and an active tumor-immune microenvironment for both 4T1 and CT26 tumor models. Combining this method with an immune checkpoint blockade can realize an improved immunotherapy efficacy and long-term protection effect for body.

DNA-enabled fluorescent-based nanosensors monitoring tumor-related RNA toward advanced cancer diagnosis: A review

As a burgeoning non-invasive indicator for reproducible cancer diagnosis, tumor-related biomarkers have a wide range of applications in early cancer screening, efficacy monitoring, and prognosis predicting. Accurate and efficient biomarker determination, therefore, is of great importance to prevent cancer progression at an early stage, thus reducing the disease burden on the entire population, and facilitating advanced therapies for cancer. During the last few years, various DNA structure-based fluorescent probes have established a versatile platform for biological measurements, due to their inherent biocompatibility, excellent capacity to recognize nucleic and non-nucleic acid targets, obvious accessibility to synthesis as well as chemical modification, and the ease of interfacing with signal amplification protocols. After decades of research, DNA fluorescent probe technology for detecting tumor-related mRNAs has gradually grown to maturity, especially the advent of fluorescent nanoprobes has taken the process to a new level. Here, a systematic introduction to recent trends and advances focusing on various nanomaterials-related DNA fluorescent probes and the physicochemical properties of various involved nanomaterials (such as AuNP, GO, MnO2, SiO2, AuNR, etc.) are also presented in detail. Further, the strengths and weaknesses of existing probes were described and their progress in the detection of tumor-related mRNAs was illustrated. Also, the salient challenges were discussed later, with a few potential solutions.

Engineered extracellular vesicles as intelligent nanosystems for next-generation nanomedicine

Extracellular vesicles (EVs), as natural carriers of bioactive cargo, have a unique micro/nanostructure, bioactive composition, and characteristic morphology, as well as fascinating physical, chemical and biochemical features, which have shown promising application in the treatment of a wide range of diseases. However, native EVs have limitations such as lack of or inefficient cell targeting, on-demand delivery, and therapeutic feedback. Recently, EVs have been engineered to contain an intelligent core, enabling them to (i) actively target sites of disease, (ii) respond to endogenous and/or exogenous signals, and (iii) provide treatment feedback for optimal function in the host. These advances pave the way for next-generation nanomedicine and offer promise for a revolution in drug delivery. Here, we summarise recent research on intelligent EVs and discuss the use of "intelligent core" based EV systems for the treatment of disease. We provide a critique about the construction and properties of intelligent EVs, and challenges in their commercialization. We compare the therapeutic potential of intelligent EVs to traditional nanomedicine and highlight key advantages for their clinical application. Collectively, this review aims to provide a new insight into the design of next-generation EV-based theranostic platforms for disease treatment.

Tumor-responsive nanomedicine based on Ce3+-modulated up-/downconversion dual-mode emission for NIR-II imaging-guided dynamic therapy

Chemodynamic therapy (CDT) and photodynamic therapy (PDT) based on intratumoral generation of reactive oxygen species (ROS) have been playing crucial roles in conquering tumors. However, the above therapeutic methods are still constrained by the overexpressed tumor glutathione (GSH) and intrinsic tumor resistance to conventional organic photosensitizers. Herein, lanthanide-doped nanoparticles (LDNPs) were coated with inorganic bimetallic copper and manganese silicate nanospheres (CMSNs) and modified with sodium alginate (SA) for second near-infrared (NIR-II, 1000-1700 nm) imaging-guided CDT and PDT. Interestingly, cross-relaxation (CR) pathways between Ce³⁺ and Ho³⁺ and CR between Ce³⁺ and Er³⁺ are fully exploited to enable dual-mode upconversion (UC) and NIR-II downconversion (DC) emissions of LDNPs under 980 nm laser excitation. UC emission can induce CMSNs to produce toxic singlet oxygen (¹O₂) for PDT, and the released Mn²⁺ and Cu⁺ ions caused by GSH-induced degradation of CMSNs can react with endogenous H₂O₂ to produce hydroxyl radical (˙OH) for CDT. Significantly, the ultrabright NIR-II DC emission endows the systems with exceptional optical imaging capabilities. All results affirm the potency of such an "all in one" theranostic nanomedicine integrating PDT, CDT and remarkable NIR-II imaging abilities accompanied by the function of modulating tumor microenvironment in cancer theranostics.

Two-Dimensional Nanomaterial-based catalytic Medicine: Theories, advanced catalyst and system design

Two-dimensional nanomaterial-based catalytic medicines that associate the superiorities of novel catalytic mechanisms with nanotechnology have emerged as absorbing therapeutic strategies for cancer therapy. Catalytic medicines featuring high efficiency and selectivity have been widely used as effective anticancer strategies without applying traditional nonselective and highly toxic chemodrugs. Moreover, two-dimensional nanomaterials are characterized by distinctive physicochemical properties, such as a sizeable bandgap, good conductivity, fast electron transfer and photoelectrochemical activity. The introduction of two-dimensional nanomaterials into catalytic medicine provides a more effective, controllable, and precise antitumor strategy. In this review, different types of two-dimensional nanomaterial-based catalytic nanomedicines are generalized, and their catalytic theories, advanced catalytic pathways and catalytic nanosystem design are also discussed in detail. Notably, future challenges and obstacles in the design and further clinical transformation of two-dimensional nanomaterial-based catalytic nanomedicine are prospected.

Sustainable and cascaded catalytic hairpin assembly for amplified sensing of microRNA biomarkers in living cells

The sensing of intracellular microRNAs (miRNAs) is of significance for early-stage disease diagnosis and therapeutic monitoring. DNA is an interesting building material that can be programed into assemblies with rigid and branched structures, especially suitable for imaging intracellular biomolecules or therapeutic drug delivery. Here, by introducing the palindromic sequences into the programmable DNA hairpins, we describe an endogenous target-responsive three-way branched and palindrome-assisted catalytic hairpin assembly (3W-pCHA) approach for imaging miRNA-155 of living tumor cells with high sensitivity. The miRNA-155 triggers autonomous assembly of the fluorescently quenched signal hairpin and two hairpin dimers formed via hybridization of their respective palindromic sequences to yield branched DNA junctions, which carry the unopened hairpins and thus provide addressable substrates for continuous assembly formation of DNA nanostructures. During the formation of the DNA nanostructures, the miRNA-155 is cyclically reused and many signal probes are unfolded to show highly intensified fluorescence for detecting miRNA-155 down to 6.9 pM in vitro with high selectivity. More importantly, these probes can be transfected into live cancer cells to initiate the assembly process triggered by intracellular miRNA-155, which provides a new way for imaging highly under-expressed miRNAs in cells. Besides, this approach can also be employed to differentiate miRNA-155 expression variations in different cells, indicating its promising potentials for early-stage disease diagnosis and biological studies in cells.

A bifunctional fluorescent probe based on "AND logic" for the simultaneous recognition of H2S/HNO and its bioimaging applications

The reaction of NO and H₂S to form HNO is a classical pathway in physiological conditions. The reported single recognition-type fluorescent probes are difficult to track precisely the relationships of H₂S and HNO. It is necessary to develop a bifunctional fluorescence probe (NJA) for monitoring simultaneously the production of endogenous HNO and H₂S. Using 7-Nitrobenzofurazan (NBD) and 2-(diphenylphosphine) benzoate as recognition sites, the obatined NJA can detect specifically HS^- and HNO. The detection limit of HS^- and HNO are 0.46 μM and 1.42 μM, respectively. Based on the dual recognition sites and input signals of the probe, a molecular "AND" logic gate was established to detect successfully H₂S and HNO in MCF-7 cells. NJA based on "AND logic" provided a simple and robust tool for monitoring the production of endogenous HNO correlative with H₂S and NO in living cells.

Perfluorooctyl bromide nanoemulsions holding MnO2 nanoparticles with dual-modality imaging and glutathione depletion enhanced HIFU-eliciting tumor immunogenic cell death

Tumor-targeted immunotherapy is a remarkable breakthrough, offering the inimitable advantage of specific tumoricidal effects with reduced immune-associated cytotoxicity. However, existing platforms suffer from low efficacy, inability to induce strong immunogenic cell death (ICD), and restrained capacity of transforming immune-deserted tumors into immune-cultivated ones. Here, an innovative platform, perfluorooctyl bromide (PFOB) nanoemulsions holding MnO₂ nanoparticles (MBP), was developed to orchestrate cancer immunotherapy, serving as a theranostic nanoagent for MRI/CT dual-modality imaging and advanced ICD. By simultaneously depleting the GSH and eliciting the ICD effect via high-intensity focused ultrasound (HIFU) therapy, the MBP nanomedicine can regulate the tumor immune microenvironment by inducing maturation of dendritic cells (DCs) and facilitating the activation of CD8⁺ and CD4⁺ T cells. The synergistic GSH depletion and HIFU ablation also amplify the inhibition of tumor growth and lung metastasis. Together, these findings inaugurate a new strategy of tumor-targeted immunotherapy, realizing a novel therapeutics paradigm with great clinical significance.

Chemodynamic Therapy via Fenton and Fenton-Like Nanomaterials: Strategies and Recent Advances

Chemodynamic therapy (CDT), a novel cancer therapeutic strategy defined as the treatment using Fenton or Fenton-like reaction to produce •OH in the tumor region, was first proposed by Bu, Shi, and co-workers in 2016. Recently, with the rapid development of Fenton and Fenton-like nanomaterials, CDT has attracted tremendous attention because of its unique advantages: 1) It is tumor-selective with low side effects; 2) the CDT process does not depend on external field stimulation; 3) it can modulate the hypoxic and immunosuppressive tumor microenvironment; 4) the treatment cost of CDT is low. In addition to the Fe-involved CDT strategies, the Fenton-like reaction-mediated CDT strategies have also been proposed, which are based on many other metal elements including copper, manganese, cobalt, titanium, vanadium, palladium, silver, molybdenum, ruthenium, tungsten, cerium, and zinc. Moreover, CDT has been combined with other therapies like chemotherapy, radiotherapy, phototherapy, sonodynamic therapy, and immunotherapy for achieving enhanced anticancer effects. Besides, there have also been studies that extend the application of CDT to the antibacterial field. This review introduces the latest advancements in the nanomaterials-involved CDT from 2018 to the present and proposes the current limitations as well as future research directions in the related field.

Recent Advances of Manganese-Based Hybrid Nanomaterials for Cancer Precision Medicine

Cancer precision medicine (CPM) could tailor the best treatment for individual cancer patients, while imaging techniques play important roles in its application. With the characteristics of noninvasion, nonionized, radiation-free, multidimensional imaging function, and real-time monitoring, magnetic resonance imaging (MRI) is an effective way for early tumor detection, and it has become a tower of strength in CPM imaging techniques. Due to linkage with nephrogenic systemic fibrosis (NSF), gadolinium (Gd)-based contrast agent (CA), which was long used in MRI, has been restricted by the Food and Drug Administration (FDA). In this review, we would like to introduce the manganese (Mn)-based CAs that could significantly increase the safety of MRI CAs by realizing more superior performance and functions simultaneously in the diagnosis and treatment of tumors. Also, recent advances in Mn-based hybrid nanomaterials for CPM are summarized and discussed.

Tumor microenvironments self-activated nanoscale metal-organic frameworks for ferroptosis based cancer chemodynamic/photothermal/chemo therapy

Ferroptosis, as a newly discovered cell death form, has become an attractive target for precision cancer therapy. Several ferroptosis therapy strategies based on nanotechnology have been reported by either increasing intracellular iron levels or by inhibition of glutathione (GSH)-dependent lipid hydroperoxidase glutathione peroxidase 4 (GPX4). However, the strategy by simultaneous iron delivery and GPX4 inhibition has rarely been reported. Herein, novel tumor microenvironments (TME)-activated metal-organic frameworks involving Fe & Cu ions bridged by disulfide bonds with PEGylation (FCSP MOFs) were developed, which would be degraded specifically under the redox TME, simultaneously achieving GSH-depletion induced GPX4 inactivation and releasing Fe ions to produce ROS via Fenton reaction, therefore causing ferroptosis. More ROS could be generated by the acceleration of Fenton reaction due to the released Cu ions and the intrinsic photothermal capability of FCSP MOFs. The overexpressed GSH and H₂O₂ in TME could ensure the specific TME self-activated therapy. Better tumor therapeutic efficiency could be achieved by doxorubicin (DOX) loading since it can not only cause apoptosis, but also indirectly produce H₂O₂ to amplify Fenton reaction. Remarkable anti-tumor effect of obtained FCSP@DOX MOFs was verified via both in vitro and in vivo assays.

A Noninvasive Gut-to-Brain Oral Drug Delivery System for Treating Brain Tumors

Most orally administered drugs fail to reach the intracerebral regions because of the intestinal epithelial barrier (IEB) and the blood-brain barrier (BBB), which are located between the gut and the brain. Herein, an oral prodrug delivery system that can overcome both the IEB and the BBB noninvasively is developed for treating gliomas. The prodrug is prepared by conjugating an anticancer drug on β-glucans using a disulfide-containing linker. Following oral administration in glioma-bearing mice, the as-prepared prodrug can specifically target intestinal M cells, transpass the IEB, and be phagocytosed/hitchhiked by local macrophages (Mϕ). The Mϕ-hitchhiked prodrug is transported to the circulatory system via the lymphatic system, crossing the BBB. The tumor-overexpressed glutathione then cleaves the disulfide bond within the prodrug, releasing the active drug, improving its therapeutic efficacy. These findings reveal that the developed prodrug may serve as a gut-to-brain oral drug delivery platform for the well-targeted treatment of gliomas.

MicroRNAs Involved in Oxidative Stress Processes Regulating Physiological and Pathological Responses

Oxidative stress influences several physiological and pathological cellular events, including cell differentiation, excessive growth, proliferation, apoptosis, and the inflammatory response. Therefore, oxidative stress is involved in the pathogenesis of various diseases, including pulmonary fibrosis, epilepsy, hypertension, atherosclerosis, Parkinson's disease, cardiovascular disease, and Alzheimer's disease. Recent studies have shown that several microRNAs (miRNAs) are involved in developing various diseases caused by oxidative stress and that miRNAs may be helpful to determine the inflammatory characteristics of immune responses during infection and disease. This review describes the known effects of miRNAs on reactive oxygen species to induce oxidative stress and the miRNA regulatory mechanisms involved in the uncoupling of Keap1-Nrf2 complexes. Finally, we summarized the functions of miRNAs in several antioxidant genes. Understanding the crosstalk between miRNAs and oxidative stress-inducing factors during physiological and pathological cellular events may have implications for designing more effective treatments for immune diseases.

Agmatine-grafted bioreducible poly(l-lysine) for gene delivery with low cytotoxicity and high efficiency

Bioreducible cationic polymers have gained considerable attention in gene delivery due to their low cytotoxicity and high efficiency. In the present work, we reported a cationic polymer, poly(disulfide-l-lysine)-g-agmatine (denoted as SSL-AG), and evaluated its ability to transfer pEGFP-ZNF580 plasmid (pZNF580) into human umbilical vein endothelial cells (HUVECs). This SSL-AG polymeric carrier efficiently condensed pZNF580 into positively charged particles (<200 nm) through electrostatic interaction. This carrier also exhibited excellent buffering capacity in the physiological environment, good pDNA protection against enzymatic degradation and rapid pDNA release in a highly reducing environment mainly because of the responsive cleavage of disulfide bonds in the polymer backbone. The hemolysis assay and in vitro cytotoxicity assay suggested that the SSL-AG carrier and corresponding gene complexes possessed both good hemocompatibility and great cell viability in HUVECs. The cellular uptake of the SSL-AG/Cy5-oligonucleotide group was 3.6 times that of the poly(l-lysine)/Cy5-oligonucleotide group, and its mean fluorescence intensity value was even higher than that of the PEI 25 kDa/Cy5-oligonucleotide group. Further, the intracellular trafficking results demonstrated that the SSL-AG/Cy5-oligonucleotide complexes exhibited a high nucleus co-localization rate (CLR) value (36.0 ± 2.8%, 3.4 times that of the poly (l-lysine)/Cy5-oligonucleotide group, 1.6 times that of the poly(disulfide-l-lysine)-g-butylenediamine/Cy5-oligonucleotide group) at 24 h, while the endo/lysosomal CLR value was relatively low. This suggested that SSL-AG successfully delivered plasmid into HUVECs with high cellular uptake, rapid endosomal escape and efficient nuclear accumulation owing to the structural advantages of the bioreducible and agmatine groups. In vitro transfection assay also verified the enhanced transfection efficiency in the SSL-AG/pZNF580 group. Furthermore, the results of CCK-8, cell migration and in vitro/vivo angiogenesis assays revealed that pZNF580 delivered by SSL-AG could effectively enhance the proliferation, migration and vascularization of HUVECs. In a word, the SSL-AG polymer has great potential as a safe and efficient gene carrier for gene therapy.

High-Performance Self-Cascade Pyrite Nanozymes for Apoptosis-Ferroptosis Synergistic Tumor Therapy

As next-generation artificial enzymes, nanozymes have shown great promise for tumor catalytic therapy. In particular, their peroxidase-like activity has been employed to catalyze hydrogen peroxide (H₂O₂) to produce highly toxic hydroxyl radicals (^•OH) to kill tumor cells. However, limited by the low affinity between nanozymes with H₂O₂ and the low level of H₂O₂ in the tumor microenvironment, peroxidase nanozymes usually produced insufficient ^•OH to kill tumor cells for therapeutic purposes. Herein, we present a pyrite peroxidase nanozyme with ultrahigh H₂O₂ affinity, resulting in a 4144- and 3086-fold increase of catalytic activity compared with that of classical Fe₃O₄ nanozyme and natural horseradish peroxidase, respectively. We found that the pyrite nanozyme also possesses intrinsic glutathione oxidase-like activity, which catalyzes the oxidation of reduced glutathione accompanied by H₂O₂ generation. Thus, the dual-activity pyrite nanozyme constitutes a self-cascade platform to generate abundant ^•OH and deplete reduced glutathione, which induces apoptosis as well as ferroptosis of tumor cells. Consequently, it killed apoptosis-resistant tumor cells harboring KRAS mutation by inducing ferroptosis. The pyrite nanozyme also exhibited favorable tumor-specific cytotoxicity and biodegradability to ensure its biosafety. These results indicate that the high-performance pyrite nanozyme is an effective therapeutic reagent and may aid the development of nanozyme-based tumor catalytic therapy.

Recent advances in visual detection for cancer biomarkers and infectious pathogens

It is an urgency to detect infectious pathogens or cancer biomarkers using rapid, simple, convenient and cost-effective methods in complex biological samples. Many existing approaches (traditional virus culture, ELISA or PCR) for the pathogen and biomarker assays face several challenges in the clinical applications that require lengthy time, sophisticated sample pre-treatment and expensive instruments. Due to the simple and rapid detection manner as well as no requirement of expensive equipment, many visual detection methods have been considered to resolve the aforementioned problems. Meanwhile, various new materials and colorimetric/fluorescent methods have been tried to construct new biosensors for infectious pathogens and biomarkers. However, the recent progress of these aspects is rarely reviewed, especially in terms of integration of new materials, microdevice and detection mechanism into the visual detection systems. Herein, we provide a broad field of view to discuss the recent progress in the visual detection of infectious pathogens and cancer biomarkers along with the detection mechanism, new materials, novel detection methods, special targets as well as multi-functional microdevices and systems. The novel visual approaches for the infectious pathogens and biomarkers, such as bioluminescence resonance energy transfer (BRET), metal-induced metallization and clustered regularly interspaced short palindromic repeats (CRISPR)-based biosensors, are discussed. Additionally, recent advancements in visual assays utilizing various new materials for proteins, nucleic acids, viruses, exosomes and small molecules are comprehensively reviewed. Future perspectives on the visual sensing systems for infectious pathogens and cancers are also proposed.

A Redox-Responsive, In-Situ Polymerized Polyplatinum(IV)-Coated Gold Nanorod as An Amplifier of Tumor Accumulation for Enhanced Thermo-Chemotherapy

It remains a major challenge to develop an effective therapeutic system based on gold nanorods (GNRs) for cancer therapy. Herein, we developed a redox-responsive, in-situ polymerized polyplatinum(IV)-coated gold nanorod (GNR@polyPt(IV)) with coupling of the near-infrared (NIR)-induced hyperthermal effect and redox-triggered drug release in one therapeutic platform as an amplifier of tumor accumulation through mild hyperthermia for enhanced synergistical thermo-chemotherapy. After in-situ polymerized with 2-methacryloyloxy ethyl phosphorylcholine (MPC) and Pt(IV) complex-based prodrug monomer (PPM) onto the surface of GNRs, the nanosized GNR@polyPt(IV) exhibited the advantages of high drug encapsulation efficiency, triggered drug release, and reduced side effect. As demonstrated by thermal imaging and photoacoustic imaging in vitro and in vivo, this GNR@polyPt(IV) exhibited an excellent NIR-associated hyperthermal effect and outstanding capacity of tumor accumulation. Importantly, under a mild hyperthermia process, the vascular endothelial growth factor (VEGF) and hypoxia-inducible factor-1α (HIF-1α) were upregulation, resulting in angiogenic vessel around the tumor. Combination with accelerated blood flow and angiogenesis by mild hyperthermia, a dramatic increase of drug accumulation in tumor could be realized after systematic administration. As a result, this amplification fashion of tumor accumulation would contribute the GNR@polyPt(IV) to inhibit tumor progression effectively. Such a facile and simple methodology for enhanced therapeutic effect based on GNRs holds great promises for cancer therapy with further development.

All-in-One Theranostic Nanomedicine with Ultrabright Second Near-Infrared Emission for Tumor-Modulated Bioimaging and Chemodynamic/Photodynamic Therapy

Reactive oxygen species (ROS)-based therapeutic modalities including chemodynamic therapy (CDT) and photodynamic therapy (PDT) hold great promise for conquering malignant tumors. However, these two methods tend to be restricted by the overexpressed glutathione (GSH) and hypoxia in the tumor microenvironment (TME). Here, we develop biodegradable copper/manganese silicate nanosphere (CMSN)-coated lanthanide-doped nanoparticles (LDNPs) for trimodal imaging-guided CDT/PDT synergistic therapy. The tridoped Yb³⁺/Er³⁺/Tm³⁺ in the ultrasmall core and the optimal Yb³⁺/Ce³⁺ doping in the shell enable the ultrabright dual-mode upconversion (UC) and downconversion (DC) emissions of LDNPs under near-infrared (NIR) laser excitation. The luminescence in the second near-infrared (NIR-II, 1000-1700 nm) window offers deep-tissue penetration, high spatial resolution, and reduced autofluorescence when used for optical imaging. Significantly, the CMSNs are capable of relieving the hypoxic TME through decomposing H₂O₂ to produce O₂, which can react with the sample to generate ¹O₂ upon excitation of UC photons (PDT). The GSH-triggered degradation of CMSNs results in the release of Fenton-like Mn²⁺ and Cu⁺ ions for ^•OH generation (CDT); simultaneously, the released Mn²⁺ ions couple with NIR-II luminescence imaging, computed tomography (CT) imaging, and magnetic resonance (MR) imaging of LDNPs, performing a TME-amplified trimodal effect. In such a nanomedicine, the TME modulation, bimetallic silicate photosensitizer, Fenton-like nanocatalyst, and NIR-II/MR/CT contrast agent were achieved "one for all", thereby realizing highly efficient tumor theranostics.

Spatiotemporally Controllable MicroRNA Imaging in Living Cells via a Near-Infrared Light-Activated Nanoprobe

In situ spatiotemporal microRNA (miRNA) imaging in mammal cells plays an essential role in illustrating its structures and biological functions. Herein, we proposed a near-infrared (NIR) light-activated nanoprobe for high-sensitive in situ controllable miRNA imaging in living cells. The NIR-activated nanoprobe employed an upconversion nanoparticle that acted as a NIR-to-UV transducer to trigger the following photocleavage toward a dumbbell DNA probe tethered on the surface of the nanoparticle. The structure change of the dumbbell probe then induced a catalytic hairpin assembly of target miRNAs, by which in situ readout of the amplified fluorescence signal was enabled. Additionally, both intracellular miRNA imaging and accurate quantification in live cells were realized without damaging the cell membranes. Compared with conventional in situ strategies, the proposed approach remarkedly increases imaging efficiency by eliminating those unfavored intercellular molecular imaging backgrounds. We assured that the proposed NIR-activated miRNA sensing strategy will add to the advancement for bioanalysis in living systems, which is of crucial importance in the diagnosis of various human diseases, especially cancers.

Yolk-shell nanovesicles endow glutathione-responsive concurrent drug release and T1 MRI activation for cancer theranostics

The effort of incorporating therapeutic drugs with imaging agents has been one of the mainstreams of nanomedicine, which holds great promise in cancer treatment in terms of monitoring therapeutic drug activity and evaluating prognostic index. However, it is still technically challenging to develop nanomedicine endowing a spatiotemporally controllable mechanism of drug release and activatable imaging capability. Here, we developed a yolk-shell type of GSH-responsive nanovesicles (NVs) in which therapeutic drug (Doxorubicin, DOX) and magnetic resonance imaging (MRI) contrast agent (ultrasmall paramagnetic iron oxide nanoparticles, USPIO NPs) formed complexes (denoted as USD) and were encapsulated inside the NVs. The formation of USD complexes is mediated by both the electrostatic adsorption between DOX and poly(acrylic acid) (PAA) polymers and the DOX-iron coordination effect on USPIO NPs. The obtained USD NVs showed a unique yolk-shell structure with restrained drug activity and quenched T1 MRI contrast ability which, on the other hand, can respond to glutathione (GSH) and lead to drug release and T1 contrast activation in a spatiotemporally concurrent manner. Furthermore, the USD NVs exhibited great potential to kill HCT116 cancer cells in vitro and effectively inhibit the tumor growth in vivo. This study may shed light on the design of sophisticated nanotheranostics in precision nanomedicine.

Metal-Based Nanocatalyst for Combined Cancer Therapeutics

As a classical nanocatalyst-based therapeutic modality, chemodynamic therapy (CDT) has received more and more attention. To improve the therapeutic efficacy of CDT, various metal-based nanocatalysts have been designed and constructed to catalyze the Fenton or Fenton-like reaction in the past few years. However, the therapeutic efficacy of certain CDT is still restricted by the tumor microenvironment, such as limited concentration of intracellular H₂O₂, inappropriate pH condition, as well as overexpressed glutathione (GSH). Therefore, many other therapeutic modalities, such as photodynamic therapy (PDT), photothermal therapy (PTT), starvation therapy, chemotherapy, and gas therapy, have been utilized to combine with CDT for increasing the tumor treatment performance. In this review, we summarized the development of combinatory therapeutic modalities based on CDT in recent years.

Applications of Two-Dimensional Nanomaterials in Breast Cancer Theranostics

Breast cancer is the leading cause of cancer-related mortality among women. Early stage diagnosis and treatment of this cancer are crucial to patients' survival. In addition, it is important to avoid severe side effects during the process of conventional treatments (surgery, chemotherapy, hormonal therapy, and targeted therapy) and increase the patients' quality of life. Over the past decade, nanomaterials of all kinds have shown excellent prospects in different aspects of oncology. Among them, two-dimensional (2D) nanomaterials are unique due to their physical and chemical properties. The functional variability of 2D nanomaterials stems from their large specific surface area as well as the diversity of composition, electronic configurations, interlayer forces, surface functionalities, and charges. In this review, the current status of 2D nanomaterials in breast cancer diagnosis and therapy is reviewed. In this respect, sensing of the tumor biomarkers, imaging, therapy, and theranostics are discussed. The ever-growing 2D nanomaterials are building blocks for the development of a myriad of nanotheranostics. Accordingly, there is the possibility to explore yet novel properties, biological effects, and oncological applications.

Manganese Oxide Nanomaterials: Synthesis, Properties, and Theranostic Applications

Despite the comprehensive applications in bioimaging, biosensing, drug/gene delivery, and tumor therapy of manganese oxide nanomaterials (MONs including MnO₂ , MnO, Mn₂ O₃ , Mn₃ O₄ , and MnO_x ) and their derivatives, a review article focusing on MON-based nanoplatforms has not been reported yet. Herein, the representative progresses of MONs on synthesis, heterogene, properties, surface modification, toxicity, imaging, biodetection, and therapy are mainly introduced. First, five kinds of primary synthetic methods of MONs are presented, including thermal decomposition method, exfoliation strategy, permanganates reduction method, adsorption-oxidation method, and hydro/solvothermal. Second, the preparations of hollow MONs and MON-based composite materials are summarized specially. Then, the chemical properties, surface modification, and toxicity of MONs are discussed. Next, the diagnostic applications including imaging and sensing are outlined. Finally, some representative rational designs of MONs in photodynamic therapy, photothermal therapy, chemodynamic therapy, sonodynamic therapy, radiotherapy, magnetic hyperthermia, chemotherapy, gene therapy, starvation therapy, ferroptosis, immunotherapy, and various combination therapy are highlighted.

Stimuli-activatable nanomedicines for chemodynamic therapy of cancer

Chemodynamic therapy (CDT) takes the advantages of Fenton-type reactions triggered by endogenous chemical energy to generate highly cytotoxic hydroxyl radicals. As a novel modality for cancer treatment, CDT shows minimal invasiveness and high tumor specificity by responding to the acidic and the highly concentrated hydrogen peroxide microenvironment of tumor. The CDT approach for spatiotemporal controllable reactive oxygen species generation exhibits preferable therapeutic performance and satisfying biosafety. In this review article, we summarized the recent advances of stimuli-activatable nanomedicines for CDT. We also overviewed the strategies for augmenting CDT performance, including increasing the catalytic efficacy through rational design of the nanomaterials, modulating the reaction condition, inputting external energy field, and regulating the tumor microenvironment. Furthermore, we discussed the potential and challenges of stimuli-activatable nanomedicine for clinical translation and future development of CDT. This article is categorized under: Therapeutic Approaches and Drug Discovery > Nanomedicine for Oncologic Disease Nanotechnology Approaches to Biology > Nanoscale Systems in Biology Diagnostic Tools > In Vivo Nanodiagnostics and Imaging.

MicroRNA-346 inhibits the growth of glioma by directly targeting NFIB

Background

Glioma is considered one of the most common tumors and has a poor prognosis. Recently, microRNAs (miRNAs) have been reported to be strongly linked to various human tumors including glioma. In this study, we investigated a new anticancer miRNA, miR-346, to determine the effects and mechanism of miR-346 and its downstream target gene NFIB on tumors.

Methods

Lentivirus transfection, real-time PCR, western blotting, immunohistochemistry, cell proliferation assays, and mouse experiments were used to examine the relationship between miR-346 and its regulation of NFIB in glioma cells.

Results

The expression of miR-346 was downregulated in glioma cells. Overexpression of miR-346 arrested the cell cycle of glioma cells and inhibited their proliferation in vitro and in vivo. NFIB was a direct target of miR-346, whose expression was reduced by the miRNA. Overexpression of NFIB reversed all tested functions of miR-346.

Conclusion

miR-346 inhibited the growth of glioma cells by targeting NFIB and may be a new prognostic and diagnostic biomarker for glioma.