Platinum–copper alloy nanoparticles armored with chloride ion transporter to promote electro-driven tumor inhibition

A Bimetallic Electro-Sensitizer Improves ROS Therapy by Relieving Autophagy-Induced ROS Tolerance and Immune Suppression

Reactive oxygen species (ROS)-dependent monotherapy usually demonstrates poor therapeutic outcomes, due to the accompanied activation of protective autophagy in tumor cells, which results in ROS tolerance and immune suppression. In this study, a bimetallic electro-sensitizer, Pt-Ir NPs is constructed, loaded with the autophagy inhibitor chloroquine (Pt-Ir-CQ NPs), to enhance the effectiveness of electrotherapy by inhibiting autophagy and activating anti-tumor immune responses. This novel electrotherapy platform demonstrates unique advantages, particularly in the treatment of hypoxic and immunosuppressive tumors. First, the electro-sensitizer catalyzes water molecules into ROS under electric field, achieving tumor ablation through electrotoxicity. Second, the incorporated CQ inhibits the protective autophagy induced by electrotherapy, restoring the sensitivity of tumor cells to ROS and thereby enhancing the anti-tumor effects of electrotherapy. Third, Pt-Ir-CQ NPs enhance the functionality of antigen-presenting cells and immunogenic cells through inhibiting autophagy, synergistically activating the anti-tumor immune responses along with the immunogenic cell death (ICD) effect induced by electrotherapy. This study provides a novel approach for the effective ablation and long-term inhibition of solid tumors through flexible modulation by an exogenous electric field.

Cancer cell membrane-camouflaged CuPt nanoalloy boosts chemotherapy of cisplatin prodrug to enhance anticancer effect and reverse cisplatin resistance of tumor

The biotoxicity and chemotherapeutic resistance of cisplatin (CDDP) pose a challenge for tumor therapy. Practically, the change in the therapeutic response of tumor from resistance to sensitivity are impressive but challenging. To this end, we propose a strategy of "one stone, three birds" by designing a CuPt nanoalloy to simultaneously eliminate GSH, relieve hypoxia, and promote ROS production for effectively reversing the platinum (IV) (Pt(IV), (c,c,t-[Pt(NH3)2Cl2(OOCCH2CH2COOH)2)) resistance. Notably, the CuPt nanoalloy exhibits ternary catalytic capabilities including mimicking GSH oxidase, catalase and peroxidase. With the subsequent disguise of tumor cell membrane, the CuPt nanoalloy is conferred with homologous targeting ability, making it actively recognize tumor cells and then effectively internalized by tumor cells. Upon entering tumor cell, it gives rise to GSH depletion, hypoxia relief, and oxidative stress enhancement by catalyzing the reaction of GSH and H2O2, which mitigates the vicious milieu and ultimately reinforces the tumor response to Pt(IV) treatment. In vivo results prove that combination therapy of mCuPt and Pt(IV) realizes the most significant suppression on A549 cisplatin-resistant tumor. This study provides a potential strategy to design novel nanozyme for conquering resistant tumor.

Platinum based theranostics nanoplatforms for antitumor applications

Platinum (Pt) based nanoplatforms are biocompatible nanoagents with photothermal antitumor performance, while exhibiting excellent radiotherapy sensitization properties. Pt-nanoplatforms have extensive research prospects in the realm of cancer treatment due to their highly selective and minimally invasive treatment mode with low damage, and integrated diagnosis and treatment with image monitoring and collaborative drug delivery. Platinum based anticancer chemotherapeutic drugs can kill tumor cells by damaging DNA through chemotherapy. Meanwhile, Pt-nanoplatforms also have good electrocatalytic activity, which can mediate novel electrodynamic therapy. Simultaneously, Pt(II) based compounds also have potential as photosensitizers in photodynamic therapy for malignant tumors. Pt-nanoplatforms can also modulate the immunosuppressive environment and synergistically ablate tumor cells in combination with immune checkpoint inhibitors. This article reviews the research progress of platinum based nanoplatforms in new technologies for cancer therapy, starting from widely representative examples of platinum based nanoplatforms in chemotherapy, electrodynamic therapy, photodynamic therapy, photothermal therapy, and immunotherapy. Finally, multimodal imaging techniques of platinum based nanoplatforms for biomedical diagnosis are briefly discussed.

Recent theranostic applications of hydrogen peroxide-responsive nanomaterials for multiple diseases

It is well established that hydrogen peroxide (H2O2) is associated with the initiation and progression of many diseases. With the rapid development of nanotechnology, the diagnosis and treatment of those diseases could be realized through a variety of H2O2-responsive nanomaterials. In order to broaden the application prospects of H2O2-responsive nanomaterials and promote their development, understanding and summarizing the design and application fields of such materials has attracted much attention. This review provides a comprehensive summary of the types of H2O2-responsive nanomaterials including organic, inorganic and organic-inorganic hybrids in recent years, and focused on their specific design and applications. Based on the type of disease, such as tumors, bacteria, dental diseases, inflammation, cardiovascular diseases, bone injury and so on, key examples for above disease imaging diagnosis and therapy strategies are introduced. In addition, current challenges and the outlook of H2O2-responsive nanomaterials are also discussed. This review aims to stimulate the potential of H2O2-responsive nanomaterials and provide new application ideas for various functional nanomaterials related to H2O2.

Single Atom Iron-Doped Graphic-Phase C3 N4 Semiconductor Nanosheets for Augmented Sonodynamic Melanoma Therapy Synergy with Endowed Chemodynamic Effect

Sonodynamic therapy (SDT) is a non-invasive therapeutic modality with high tissue-penetration depth to induce reactive oxygen species (ROS) generation for tumor treatment. However, the clinical translation of SDT is restricted seriously by the lack of high-performance sonosensitizers. Herein, the distinct single atom iron (Fe)-doped graphitic-phase carbon nitride (C3 N4 ) semiconductor nanosheets (Fe-C3 N4 NSs) are designed and engineered as chemoreactive sonosensitizers to effectively separate the electrons (e- ) and holes (h+ ) pairs, achieving high yields of ROS generation against melanoma upon ultrasound (US) activation. Especially, the single atom Fe doping not only substantially elevates the separation efficiency of the e- -h+ pairs involved in SDT, but also can serve as high-performance peroxidase mimetic enzyme to catalyze the Fenton reaction for generating abundant hydroxyl radicals, therefore synergistically augmenting the curative effect mediated by SDT. As verified by density functional theory simulation, the doping of Fe atom significantly promotes the charge redistribution in the C3 N4 -based NSs, which improves their synergistic SDT/chemodynamic activities. Both the in vitro and in vivo assays demonstrate that Fe-C3 N4 NSs feature an outstanding antitumor effect by aggrandizing the sono-chemodynamic effect. This work illustrates a unique single-atom doping strategy for ameliorating the sonosensitizers, and also effectively expands the innovative anticancer-therapeutic applications of semiconductor-based inorganic sonosensitizers.

Nanoplatforms Potentiated Ablation-Immune Synergistic Therapy through Improving Local Control and Suppressing Recurrent Metastasis

Minimally invasive ablation has been widely applied for treatment of various solid tumors, including hepatocellular carcinoma, renal cell carcinoma, breast carcinomas, etc. In addition to removing the primary tumor lesion, ablative techniques are also capable of improving the anti-tumor immune response by inducing immunogenic tumor cell death and modulating the tumor immune microenvironment, which may be of great benefit to inhibit the recurrent metastasis of residual tumor. However, the short-acting activated anti-tumor immunity of post-ablation will rapidly reverse into an immunosuppressive state, and the recurrent metastasis owing to incomplete ablation is closely associated with a dismal prognosis for the patients. In recent years, numerous nanoplatforms have been developed to improve the local ablative effect through enhancing the targeting delivery and combining it with chemotherapy. Particularly, amplifying the anti-tumor immune stimulus signal, modulating the immunosuppressive microenvironment, and improving the anti-tumor immune response with the versatile nanoplatforms have heralded great application prospects for improving the local control and preventing tumor recurrence and distant metastasis. This review discusses recent advances in nanoplatform-potentiated ablation-immune synergistic tumor therapy, focusing on common ablation techniques including radiofrequency, microwave, laser, and high-intensity focused ultrasound ablation, cryoablation, and magnetic hyperthermia ablation, etc. We discuss the advantages and challenges of the corresponding therapies and propose possible directions for future research, which is expected to provide references for improving the traditional ablation efficacy.

Biomimetic electrodynamic nanoparticles comprising ginger-derived extracellular vesicles for synergistic anti-infective therapy

Nanotechnology enlightens promising antibacterial strategies while the complex in vivo infection environment poses a great challenge to the rational design of nanoplatforms for safe and effective anti-infective therapy. Herein, a biomimetic nanoplatform (EV-Pd-Pt) integrating electrodynamic Pd-Pt nanosheets and natural ginger-derived extracellular vesicles (EVs) is proposed. The introduction of ginger-derived EVs greatly endows EV-Pd-Pt with prolonged blood circulation without immune clearance, as well as accumulation at infection sites. More interestingly, EV-Pd-Pt can enter the interior of bacteria in an EV lipid-dependent manner. At the same time, reactive oxygen species are sustainably generated in situ to overcome the limitations of their short lifetime and diffusion distance. Notably, EV-Pd-Pt nanoparticle-mediated electrodynamic and photothermal therapy exhibit synergistic effects. Furthermore, the desirable biocompatibility and biosafety of the proposed nanoplatform guarantee the feasibility of in vivo applications. This proof-of-concept work holds significant promise for developing biomimetic nanoparticles by exploiting their intrinsic properties for synergistic anti-infective therapy.