Polydopamine Nanostructure-Enhanced Water Interaction with pH-Responsive Manganese Sulfide Nanoclusters for Tumor Magnetic Resonance Contrast Enhancement and Synergistic Ferroptosis-Photothermal Therapy

Advances in Manganese-based nanomaterials for cancer therapy via regulating Non-Ferrous ferroptosis

Ferroptosis, a regulated form of cell death distinct from apoptosis, was first identified in 2012 and is characterized by iron-dependent lipid peroxidation driven by reactive oxygen species (ROS). Since its discovery, ferroptosis has been linked to various diseases, with recent studies highlighting its potential in cancer therapy, particularly for targeting cancer cells that are resistant to traditional treatments like chemotherapy and radiotherapy. While iron has historically been central to ferroptosis, emerging evidence indicates that non-ferrous ions, especially manganese (Mn), also play a crucial role in modulating this process. Mn-based nanomaterials have shown significant promise in cancer treatment by enhancing ROS production, depleting antioxidant defenses, and inducing ferroptosis. Additionally, these materials offer advantages in tumor imaging, immunotherapy, and catalyzing the Fenton-like reactions essential for ferroptosis. This review delves into the mechanisms of Mn-induced ferroptosis, focusing on recent advancements in Mn-based nanomaterials and their applications in chemodynamic therapy and immunotherapy. By leveraging non-ferrous ion-mediated ferroptosis, these approaches provide a novel avenue for cancer treatment. Furthermore, this review explores the potential role of Mn-based nanomaterials in the lipid metabolism pathways involved in ferroptosis and highlights the advantages of Mn ions over other metals in promoting ferroptosis. These insights offer new perspectives for the development of tumor therapies centered on Mn-based nanomaterials.

An Albumin-Photosensitizer Supramolecular Assembly with Type I ROS-Induced Multifaceted Tumor Cell Deaths for Photodynamic Immunotherapy

Photodynamic therapy holds great potentials in cancer treatment, yet its effectiveness in hypoxic solid tumor is limited by the oxygen-dependence and insufficient oxidative potential of conventional type II reactive oxygen species (ROS). Herein, the study reports a supramolecular photosensitizer, BSA@TPE-BT-SCT NPs, through encapsulating aggregation-enhanced emission photosensitizer by bovine serum albumin (BSA) to significantly enhance ROS, particularly less oxygen-dependent type I ROS for photodynamic immunotherapy. The abundant type I ROS generated by BSA@TPE-BT-SCT NPs induce multiple forms of programmed cell death, including apoptosis, pyroptosis, and ferroptosis. These multifaceted cell deaths synergistically facilitate the release of damage-associated molecular patterns and antitumor cytokines, thereby provoking robust antitumor immunity. Both in vitro and in vivo experiments confirmed that BSA@TPE-BT-SCT NPs elicited the immunogenic cell death, enhance dendritic cell maturation, activate T cell, and reduce myeloid-derived suppressor cells, leading to the inhibition of both primary and distant tumors. Additionally, BSA@TPE-BT-SCP NPs also exhibited excellent antitumor performance in a humanized mice model, evidenced by a reduction in senescent T cells among these activated T cells. The findings advance the development of robust type I photosensitizers and unveil the important role of type I ROS in enhancing multifaceted tumor cell deaths and antitumor immunogenicity.

Molecular dynamics in pharmaceutical nanotechnology: simulating interactions and advancing applications

Molecular Dynamics (MD) simulations are now widely utilized in pharmaceutical nanotechnology to gain deeper understanding of nanoscale processes imperative to drug design. This review has also detailed how MD simulation can be employed in the study of drug-nanocarrier interactions, controlling release of chemical compounds from drug delivery systems and increasing solubility and bioavailability of nanocarriers. Furthermore, MD contributes to examining the drug delivery systems, measuring the toxic effects, and determining biocompatibility of nanomedical systems. With the incorporation of artificial intelligence and the use of hybrid simulation systems, MD has gone a step ahead to model other niches of biology that make a tremendous opening to develop highly selective nanomedications. Nevertheless, with well-known issues such as computational constraints and the discrepancy between in silico and experiment results, MD remains a work in progress, with considerable promise for replacing or supplementing existing approaches to the development of precision medicine and nanomedicine, the continued progression of healthcare hopeful.

Multifunctional metal-organic frameworks with photothermal-triggered nitric oxide release for gas/photothermal synergistic cancer therapy

Photothermal therapy (PTT) utilizing cyanine dyes (Cy) and nitric oxide (NO) gas therapy via BNN6 have demonstrated significant potential in cancer treatment. However, the rapid clearance of these small molecules from the body limits their accumulation at tumor sites, thereby reducing therapeutic efficacy. To address this, we employed the acid-sensitive nanomaterial ZIF-8 as a carrier to encapsulate Cy and BNN6, creating functionalized BNN6-Cy@ZIF-8 Nanoparticles (B-C@Z NPs) for the targeted delivery and release of Cy and BNN6 at tumor sites. Within the acidic tumor microenvironment and lysosomes, ZIF-8 degrades, releasing Cy and BNN6. Under 808 nm laser irradiation, Cy exhibits excellent photothermal conversion efficiency, generating substantial heat to induce tumor cell apoptosis via PTT. Simultaneously, the elevated temperature triggers the decomposition of BNN6, releasing NO to further enhance tumor cell cytotoxicity. This synergistic approach, combining hyperthermia and NO-mediated cytotoxicity, has shown near-complete tumor eradication in vivo and in vitro, offering a promising novel strategy for cancer therapy.

Injectable polydopamine/curcumin dual-modified polylactic acid/polycaprolactone coaxial staple fibers for chronotropic treatment of oral squamous cell carcinoma

Oral squamous cell carcinoma (OSCC) is one of the most prevalent malignant tumors in the oral and maxillofacial region. Traditional treatments for OSCC, including surgery, radiotherapy, and chemotherapy, often lead to severe adverse effects. Therefore, the development of safe and effective novel cancer therapies is crucial for achieving synergistic cancer treatment, significantly enhancing patient survival and quality of life. In this study, triaxial electrospinning combined with freeze-shortening technology was employed to prepare injectable short fibers that provided a sustained release of curcumin (CUR). Subsequently, polydopamine (PDA) was modified on the surface of the short fibers to create PDA@CUR@PCL/PLA. The developed injectable short fibers represented a significant advancement in reducing the risks associated with the surgical implantation of traditional two-dimensional fibrous membranes. These fibers were coated with dopamine, which imparted notable significant photothermal effects, facilitating the rapid destruction of cancer cells. Furthermore, the core-loaded CUR was released in a pH-responsive manner and demonstrated a sustained anti-tumor effect. Cellular and animal experiments indicated that these composite short fibers could effectively eliminate oral cancer cells through a synergistic combination of photothermal and drug therapies without apparent toxic side effects. The developed injectable coaxial PDA@CUR@PCL/PLA short fibers are expected to provide a novel treatment approach for OSCC.

Customized Sized Manganese Sulfide Nanospheres as Efficient T1 MRI Contrast Agents for Enhanced Tumor Theranostics

The impact of nanoparticle size on the effectiveness of magnetic resonance imaging (MRI) using sulfurized manganese nanoparticles (MnS@PAA) stabilized with polyacrylic acid (PAA) as a binder was thoroughly investigated. MnS@PAA nanoparticles of varying sizes were synthesized by altering the ratio of ethylene glycol (EG) to diethylene glycol (DEG) during the synthesis process. These nanoparticles exhibited a uniform size distribution and demonstrated high T1 relaxation rates, along with a notable pH-responsive behavior. As the nanoparticle size increased, the T1 relaxation rate decreased, indicating that size plays a crucial role in their MRI performance. Additionally, research has revealed that the efficiency of tumor uptake by these nanoparticles is size dependent. Specifically, MnS@PAA nanoparticles with a core size of 100 nm (MS100) exhibited greater tumor accumulation and provided enhanced MRI contrast. Once within the acidic environment of a tumor, MS100 decomposes into Mn2+ and H2S. Mn2+ ions promote the generation of hydroxyl radicals, which leads to lipid peroxidation and induces ferroptosis. Concurrently, the release of H2S inhibits catalase activity, resulting in elevated levels of hydrogen peroxide (H2O2), achieving a synergistic effect between chemodynamic therapy (CDT) and gas therapy. This study explores the influence of nanoparticle size on its potential applications as an MRI contrast agent and as a therapeutic agent in cancer treatment.

Polydopamine Decorated Hyaluronic Acid Clusters for Tumor Cell Targeting Combination Therapy via Template Self-Consumption Methods

Photothermal-chemodynamic-chemotherapy (PTT-CDT-CT) combination therapy significantly enhances the therapeutic efficacy against tumors. However, synthesizing PTT-CDT-CT nanosystems is complex, typically requiring the preparation and conjugation of three components into a single carrier. To overcome this challenge, a facile template self-consumption method is developed. In this approach, hyaluronic acid (HA), recognized for its tumor cell targeting properties, chelates with Cu2+ to form Cu-HA, which then transforms into CuO2@HA cluster templates. These templates self-consume gradually, producing ·OH and Cu2+, which catalyze the rapid polymerization of dopamine and coordinate with polydopamine respectively, enhancing the photothermal conversion efficiency. After gossypol loading, GPDA@HA clusters are formed, achieving high gossypol loading efficiency due to π-π stacking between gossypol and PDA, as well as coordination between gossypol and Cu2+. The GPDA@HA clusters are effectively internalized by tumor cells through endocytosis, mediating the synergistic damage or inhibition of intracellular proteins, and nucleic acids against tumor cells via PTT, CDT, and CT. Crucially, the synergism of PTT-CDT-CT combination therapy far surpasses those of a single modality. This work introduces a new pathway for the synthesis of PTT-CDT-CT nanosystems, avoiding the conventional synthesis and loading of different therapeutic agents, and provides insights into developing personalized drug combination therapies with high efficacy.

An acidity-triggered aggregation nanoplatform based on degradable mesoporous organosilica nanoparticles for precise drug delivery and phototherapy of focal bacterial infection

It is crucial to precisely strike the bacterially infected area and avoid damaging healthy tissue in bacterial infection treatment. Herein, we report an acidity-triggered aggregation antibacterial nanoplatform based on biodegradable mesoporous organic silica nanoparticles (MON NPs). The surface of MON NPs modified with polydopamine (PDA) encapsulated ciprofloxacin (CIP) and methylene blue (MB) and was then further grafted with glycol chitosan to obtain MB/CIP@MON-PDA-GCS NPs (MCMPG NPs). In the bacterial infection environment with acidic characteristics, glycol chitosan (GCS) becomes positively charged. Consequently, the positively charged acidity-triggered GCS enables MCMPG NPs to accumulate on the negatively charged bacterial surfaces in the infected area and not in healthy tissue. The targeted method allows for the precise release of CIP and MB, ensuring the spatial accuracy of photodynamic therapy (PDT) and photothermal therapy (PTT) for effective bacteria-specific treatment.

Role of tumor-derived exosomes mediated immune cell reprograming in cancer

Tumor-derived exosomes (TDEs), as topologies of tumor cells, not only carry biological information from the mother, but also act as messengers for cellular communication. It has been demonstrated that TDEs play a key role in inducing an immunosuppressive tumor microenvironment (TME). They can reprogram immune cells indirectly or directly by delivering inhibitory proteins, cytokines, RNA and other substances. They not only inhibit the maturation and function of dendritic cells (DCs) and natural killer (NK) cells, but also remodel M2 macrophages and inhibit T cell infiltration to promote immunosuppression and create a favorable ecological niche for tumor growth, invasion and metastasis. Based on the specificity of TDEs, targeting TDEs has become a new strategy to monitor tumor progression and enhance treatment efficacy. This paper reviews the intricate molecular mechanisms underlying the immunosuppressive effects induced by TDEs to establish a theoretical foundation for cancer therapy. Additionally, the challenges of TDEs as a novel approach to tumor treatment are discussed.

Facile fabrications of poly (acrylic acid)-mesoporous zinc phosphate/polydopamine Janus nanoparticles as a biosafe photothermal therapy agent and a pH/NIR-responsive drug carrier

Balancing biocompatibility and drug-loading efficiency in nanoparticles presents a significant challenge. In this study, we describe the facile fabrication of poly (acrylic acid)-mesoporous zinc phosphate/polydopamine (PAA-mZnP/PDA) Janus nanoparticles (JNPs). The PDA half-shell itself can serve as a photothermal agent for photothermal therapy (PTT), as well as to offers sites for polyethylene glycol (PEG) to enhance biocompatibility. Concurrently, the mesoporous ZnP core allows high loading of doxorubicin (DOX) for chemotherapy and the Cy5.5 dye for fluorescence imaging. The resultant PAA-mZnP/PDA-PEG JNPs exhibit exceptional biocompatibility, efficient drug loading (0.5 mg DOX/1 mg JNPs), and dual pH/NIR-responsive drug release properties. We demonstrate the JNPs' satisfactory anti-cancer efficacy, highlighting the synergistic effects of chemotherapy and PTT. Furthermore, the potential for synergistic fluorescence imaging-guided chemo-phototherapy in cancer treatment is illustrated. Thus, this work exemplifies the development of biosafe, multifunctional JNPs for advanced applications in cancer theranostics. STATEMENT OF SIGNIFICANCE: Facile fabrication of monodispersed nanomedicine with multi-cancer killing modalities organically integrated is nontrivial and becomes more challenging under the biocompatibility requirement that is necessary for the practical applications of nanomedicines. In this study, we creatively designed PAA-mZnP/PDA JNPs and fabricated them under mild conditions. Our method reliably yields uniform JNPs with excellent monodispersity. To maximize functionalities, we achieve fourfold advantages including efficient drug/fluorescent dye loading, PTT, pH/NIR dual-responsive properties, and optimal biocompatibility. The as-fabricated JNPs exhibit satisfactory anti-cancer performance both in vitro and in vivo, and demonstrate the potential of JNPs in fluorescence imaging-guided synergistic cancer chemo-phototherapy. Overall, our research establishes a pathway in versatile inorganic/polymer JNPs for enhanced cancer diagnosis and therapy.

Mesoporous manganese nanocarrier target delivery metformin for the co-activation STING pathway to overcome immunotherapy resistance

Targeting the stimulator of interferon genes (STING) pathway is a promising strategy to overcome primary resistance to immune checkpoint inhibitors in non-small cell lung cancer with the STK11 mutation. We previously found metformin enhances the STING pathway and thus promotes immune response. However, its low concentration in tumors limits its clinical use. Here, we constructed high-mesoporous Mn-based nanocarrier loading metformin nanoparticles (Mn-MSN@Met-M NPs) that actively target tumors and respond to release higher concentration of Mn2+ ions and metformin. The NPs significantly enhanced the T cells to kill lung cancer cells with the STK11 mutant. The mechanism shows that enhanced STING pathway activation promotes STING, TBKI, and IRF3 phosphorylation through Mn2+ ions and metformin release from NPs, thus boosting type I interferon production. In vivo, NPs in combination with a PD-1 inhibitor effectively decreased tumor growth. Collectively, we developed a Mn-MSN@Met-M nanoactivator to intensify immune activation for potential cancer immunotherapy.

M2 Macrophage-Derived Small Extracellular Vesicles Ameliorate Pyroptosis and Intervertebral Disc Degeneration

Intervertebral discs (IVDs) have a limited self-regenerative capacity and current strategies for IVD regeneration are unsatisfactory. Recent studies showed that small extracellular vesicles derived from M2 macrophage cells (M2-sEVs) inhibited inflammation by delivery of various bioactive molecules to recipient cells, which indicated that M2-sEVs may offer a therapeutic strategy for the repair of IVDs. Herein, we investigated the roles and mechanisms of M2-sEVs on IVD regeneration. The in vitro results demonstrated that M2-sEVs inhibited pyroptosis, preserved cellular viability, and promoted migration of nucleus pulposus cells (NPCs). Bioinformatics analysis and verification experiments of microRNA (miR) expression showed that miR-221-3p was highly expressed in M2-sEVs. The mechanism of action was explored and indicated that M2-sEVs inhibited pyroptosis of NPCs through transfer of miR-221-3p, which suppressed the expression levels of phosphatase and tensin homolog and NOD-, LRR-, and pyrin domain-containing protein 3. Moreover, we fabricated decellularized ECM-hydrogel (dECM) for sustained release of M2-sEVs, which exhibited biocompatibility and controlled release properties. The in vivo results revealed that dECM-hydrogel containing M2-sEVs (dECM/M2-sEVs) delayed the degeneration of intervertebral disc degeneration (IDD) models. In addition to demonstrating a promising therapeutic for IDD, this study provided valuable data for furthering the understanding of the roles and mechanisms of M2-sEVs in IVD regeneration.

Metallic Copper-Based Dual-Enzyme Biomimetic Nanoplatform for Mild Photothermal Enhancement of Anticancer Catalytic Activity

Background: Chemodynamic therapy (CDT) is recognized as a promising cancer treatment. Recently, copper sulfide nanostructures have been extensively employed as Fenton-like reagents that catalyze the formation of acutely toxic hydroxyl radicals (·OH) from hydrogen peroxide (H2O2). However, CDT therapeutic potency is restricted by the tumor microenvironment (TME), such as insufficient amounts of hydrogen peroxide, excessive glutathione levels, etc. To address these disadvantages, glucose oxidase (GOx) or catalase (CAT) can be utilized to enhance CDT, while low therapeutic efficacy still inhibits their future applications. Our previous study revealed that mild photothermal effect could boost the CDT catalytic effectiveness as well as GOx enzyme activity over a range. Results: We engineered and constructed a hollow CuS nanoplatform loaded with GOx and CAT, coating with macrophage membranes (M@GOx-CAT@CuS NPs). The nanoplatforms allowed enhancement of the reactive oxygen species creation rate and GOx catalytic activeness of CDT through mild phototherapy directed by photoacoustic imaging. After actively targeting vascular cell adhesion molecule-1 (VCAM-1) in cancer cells mediated by macrophage membrane coating, M@GOx-CAT@CuS NPs released GOx and CAT under near-infrared irradiation. GOx catalyzed the formation of H2O2 and gluconic acid with glucose, creating a better catalytic environment for CDT. Meanwhile, CAT-catalyzed H2O2 decomposition to generate sufficient oxygen, appropriately alleviating the oxygen shortage in the TME. In addition, starvation effects decreased adenosine triphosphate levels and further underregulated heat shock protein expression to reduce the heat resistance of tumor cells, resulting in a better mild phototherapy outcome. Both in vitro and in vivo experiments demonstrated that the newly developed M@GOx-CAT@CuS nanoplatform has remarkable synergistic anticancer therapeutic effects. Conclusion: The cascade reaction-enhanced biomimetic nanoplatform opens up a new avenue for precision tumor diagnostic and therapeutic research.

Cancer Radiosensitization Nanoagent to Activate cGAS-STING Pathway for Molecular Imaging Guided Synergistic Radio/Chemo/Immunotherapy

Immunotherapy has emerged as an innovative strategy with the potential to improve outcomes in cancer patients. Recent evidence indicates that radiation-induced DNA damage can activate the cyclic-GMP-AMP synthase (cGAS)-stimulator of interferon genes (STING) pathway to enhance the antitumor immune response. Even so, only a small fraction of patients currently benefits from radioimmunotherapy due to the radioresistance and the inadequate activation of the cGAS-STING pathway. Herein, this work integrates hafnium oxide (HfO2) nanoparticles (radiosensitizer) and 7-Ethyl-10-hydroxycamptothecin (SN38, chemotherapy drug, STING agonist) into a polydopamine (PDA)-coated core-shell nanoplatform (HfO2@PDA/Fe/SN38) to achieve synergistic chemoradiotherapy and immunotherapy. The co-delivery of HfO2/SN38 greatly enhances radiotherapy efficacy by effectively activating the cGAS-STING pathway, which then triggers dendritic cells maturation and CD8+ T cells recruitment. Consequently, the growth of both primary and abscopal tumors in tumor-bearing mice is efficiently inhibited. Moreover, the HfO2@PDA/Fe/SN38 complexes exhibit favorable magnetic resonance imaging (MRI)/photoacoustic (PA) bimodal molecular imaging properties. In summary, these developed multifunctional complexes have the potential to intensify immune activation to realize simultaneous cancer Radio/Chemo/Immunotherapy for clinical translation.