Hypoxia-responsive Immunostimulatory Nanomedicines Synergize with Checkpoint Blockade Immunotherapy for Potentiating Cancer Immunotherapy

Four-component of double-layer infinite coordination polymer nanocomposites for large tumor trimodal therapy via multi high-efficiency synergies

Multimodal /components tumors synergistic therapy is a crucial approach for enhancing comprehensive efficacy. Our research has identified lots of high efficiency synergies among four suitable components, revealing combinations with remarkably low combination index (CI) values (10-3-10-8). These combinations hold promise for large tumor powerful electrothermal-thermodynamic-multi-chemo trimodal therapy. To implement this approach, we developed four-component of double-layer infinite coordination polymer (ICP) nanocomposites, in which hypoxia-activated AQ4N and thermodynamic agent AIPH coordinated with Cu(Ⅱ) to form initial layer of positively charged ICPs-l NPs, chemotherapeutic agents gossypol-hyaluronic acid (G-HA) and CA4 coordinated with Fe(Ⅲ) to form out layer of negatively charged ICPs-2 NPs, then double-layer infinite coordination polymer nanocomposites (ICPs-1@ICPs-2 CNPs) were fabricated by electrostatic adsorption using ICPs-l NPs and ICPs-2 NPs. Cell experiments have extensively optimized the coordination combinations of the four components and the composition of the two layers. A programmable three-stage therapeutic procedure, assisted by a micro-electrothermal needle (MEN), was developed. Under this procedure the resulting nanocomposites demonstrate the powerful trimodal comprehensive therapeutic outcomes for large tumors using lower components dosage, achieving a tumor inhibition rate nearly reaching 100 % and no recurrence for 60 days. This study offers remarkable potential for tumor multimodal /components synergistic therapy in future.

Cuttlefish-Inspired Photo-Responsive Antibacterial Microparticles with Natural Melanin Nanoparticles Spray

Topical antibiotics can be utilized to treat periodontitis, while their delivery stratagems with controlled release and long-lasting bactericidal inhibition are yet challenging. Herein, inspired by the defensive behavior of cuttlefish expelling ink, this work develops innovative thermal-responsive melanin-integrated porous microparticles (MPs) through microfluidic synthesis for periodontitis treatment. These MPs are composed of melanin nanoparticles (NPs), poly(N-isopropylacrylamide) (PNIPAM), and agarose. Benefiting from the excellent biocompatibility and large surface area ratio of MPs, they can deliver abundant melanin NPs. Under near-infrared irradiation, the melanin NPs can convert photo energy into thermal energy. This leads to agarose melting and subsequent shrinkage of the microspheres induced by pNIPAM, thereby facilitating the release of melanin NPs. In addition, the released melanin NPs can serve as a highly effective photothermal agent, displaying potent antibacterial activity against porphyromonas gingivalis and possessing natural anti-inflammatory properties. These unique characteristics are further demonstrated through in vivo experiments, showing the antibacterial effects in the treatment of infected wounds and periodontitis. Therefore, the catfish-inspired photo-responsive antibacterial MPs with controlled-release drug delivery hold tremendous potential in clinical antibacterial applications.

Carbon Free Radical (R⋅) Inactivates NF-κB for Radical Capping Therapy

Inactivating hyperactivated transcription factors can overcome tumor therapy resistance, but their undruggable features limit the development of conventional inhibitors. Here, we report that carbon-centered free radicals (R⋅) can inactivate NF-κB transcription by capping the active sites in both NF-κB and DNA. We construct a type of thermosensitive R⋅ initiator loaded amphiphilic nano-micelles to facilitate intracellular delivery of R⋅. At a temperature of 43 °C, the generated R⋅ engage in electrophilic radical addition towards double bonds in nucleotide bases, and simultaneously cap the sulfhydryl residues in NF-κB through radical chain reaction. As a result, both NF-κB nuclear translocation and NF-κB-DNA binding are suppressed, leading to a remarkable NF-κB inhibition of up to 94.1 %. We have further applied R⋅ micelles in a clinical radiofrequency ablation tumor therapy model, showing remarkable NF-κB inactivation and consequently tumor metastasis inhibition. Radical capping strategy not only provides a method to solve the heat-sink effect in clinic tumor hyperthermia, but also suggests a new perspective for controllable modification of biomacromolecules in cancer therapy.

Mucus and Biofilm Penetrating Nanoplatform as an Ultrasound-Induced Free Radical Initiator for Targeted Treatment of Helicobacter pylori Infection

Helicobacter pylori (H. pylori) infection is closely associated with the development of various gastric diseases. The effectiveness of current clinical antibiotic therapy is hampered by the rise of drug-resistant strains and the formation of H. pylori biofilm. This paper reports a sonodynamic nanocomposite PtCu3-PDA@AIPH@Fucoidan (PPAF), which consists of dopamine-modified inorganic sonosensitizers PtCu3, alkyl radicals (R•) generator AIPH and fucoidan, can penetrate the mucus layer, target H. pylori, disrupt biofilms, and exhibit excellent bactericidal ability. In vitro experiments demonstrate that PPAF exhibits excellent acoustic kinetic properties, generating a significant amount of reactive oxygen species and oxygen-independent R• for sterilization under ultrasound stimulation. Simultaneously, the produced N2 can enhance the cavitation effect, aiding PPAF nanoparticles in penetrating the gastric mucus layer and disrupting biofilm integrity. This disruption allows more PPAF nanoparticles to bind to biofilm bacteria, facilitating the eradication of H. pylori. In vivo experiments demonstrate that ultrasound-stimulated PPAF exhibited significant antibacterial efficacy against H. pylori. Moreover, it effectively modulated the expression levels of inflammatory factors and maintained gastrointestinal microbiota stability when compared to the antibiotic treatment group. In summary, PPAF nanoparticles present a potential alternative to antibiotics, offering an effective and healthy option for treating H. pylori infection.

Nanomaterials-Involved Tumor-Associated Macrophages' Reprogramming for Antitumor Therapy

Tumor-associated macrophages (TAMs) play pivotal roles in tumor development. As primary contents of tumor environment (TME), TAMs secrete inflammation-related substances to regulate tumoral occurrence and development. There are two kinds of TAMs: the tumoricidal M1-like TAMs and protumoral M2-like TAMs. Reprogramming TAMs from immunosuppressive M2 to immunocompetent M1 phenotype is considered a feasible way to improve immunotherapeutic efficiency. Notably, nanomaterials show great potential for biomedical fields due to their controllable structures and properties. There are many types of nanomaterials that exhibit great regulatory activities for TAMs' reprogramming. In this review, the recent progress of nanomaterials-involved TAMs' reprogramming is comprehensively discussed. The various nanomaterials for TAMs' reprogramming and the reprogramming strategies are summarized and introduced. Additionally, the challenges and perspectives of TAMs' reprogramming for efficient therapy are discussed, aiming to provide inspiration for TAMs' regulator design and promote the development of TAMs-mediated immunotherapy.

Nanocatalysts for modulating antitumor immunity: fabrication, mechanisms and applications

Immunotherapy harnesses the inherent immune system in the body to generate systemic antitumor immunity, offering a promising modality for defending against cancer. However, tumor immunosuppression and evasion seriously restrict the immune response rates in clinical settings. Catalytic nanomedicines can transform tumoral substances/metabolites into therapeutic products in situ, offering unique advantages in antitumor immunotherapy. Through catalytic reactions, both tumor eradication and immune regulation can be simultaneously achieved, favoring the development of systemic antitumor immunity. In recent years, with advancements in catalytic chemistry and nanotechnology, catalytic nanomedicines based on nanozymes, photocatalysts, sonocatalysts, Fenton catalysts, electrocatalysts, piezocatalysts, thermocatalysts and radiocatalysts have been rapidly developed with vast applications in cancer immunotherapy. This review provides an introduction to the fabrication of catalytic nanomedicines with an emphasis on their structures and engineering strategies. Furthermore, the catalytic substrates and state-of-the-art applications of nanocatalysts in cancer immunotherapy have also been outlined and discussed. The relationships between nanostructures and immune regulating performance of catalytic nanomedicines are highlighted to provide a deep understanding of their working mechanisms in the tumor microenvironment. Finally, the challenges and development trends are revealed, aiming to provide new insights for the future development of nanocatalysts in catalytic immunotherapy.

Mn(iii)-mediated carbon-centered radicals generate an enhanced immunotherapeutic effect

A strategy for designing cancer therapeutic nanovaccines based on immunogenic cell death (ICD)-inducing therapeutic modalities is particularly attractive for optimal therapeutic efficacy. In this work, a highly effective cancer therapeutic nanovaccine (denoted as MPL@ICC) based on immunogenic photodynamic therapy (PDT) was rationally designed and fabricated. MPL@ICC was composed of a nanovehicle of MnO2 modified with a host-guest complex using amino pillar[6]arene and lactose-pyridine, a prodrug of isoniazid (INH), and chlorine e6 (Ce6). The nanovaccine exhibited excellent biosafety, good targeting ability to hepatoma cells and enrichment at tumor sites. Most importantly, it could modulate the tumor microenvironment (TME) to facilitate the existence of Mn(iii) and Mn(iii)-mediated carbon-centered radical generation with INH released from the prodrug in situ to further strengthen ICD. This is the first report on Mn(iii)-mediated generation of carbon-centered radicals for successful anti-tumor immunotherapy using ICD, which provides a novel strategy for designing highly efficient cancer therapeutic nanovaccines.

Optimized strategies of ROS-based nanodynamic therapies for tumor theranostics

Reactive oxygen species (ROS) play a crucial role in regulating the metabolism of tumor growth, metastasis, death and other biological processes. ROS-based nanodynamic therapies (NDTs) are becoming attractive due to non-invasive, low side effects and tumor-specific advantages. NDTs have rapidly developed into numerous branches, such as photodynamic therapy, chemodynamic therapy, sonodynamic therapy and so on. However, the complexity of the tumor microenvironment and the limitations of existing sensitizers have greatly restricted the therapeutic effects of NDTs, which heavily rely on ROS levels. To address the limitations of NDTs, various strategies have been developed to increase ROS yield, which is an urgent aspect for the positive development of NDTs. In this review, the nanodynamic potentiation strategies in terms of unique properties and universalities of NDTs are comprehensively outlined. We mainly summarize the current dilemmas faced by each NDT and the respective solutions. Meanwhile, the NDTs universalities-based potentiation strategies and NDTs-based combined treatments are elaborated. Finally, we conclude with a discussion of the key issues and challenges faced in the development and clinical transformation of NDTs.

Melanin/melanin-like nanoparticles: As a naturally active platform for imaging-guided disease therapy

The development of biocompatible and efficient nanoplatforms that combine diagnostic and therapeutic functions is of great importance for precise disease treatment. Melanin, an endogenous biopolymer present in living organisms, has attracted increasing attention as a versatile bioinspired functional platform owing to its unique physicochemical properties (e.g., high biocompatibility, strong chelation of metal ions, broadband light absorption, high drug binding properties) and inherent antioxidant, photoprotective, anti-inflammatory, and anti-tumor effects. In this review, the fundamental physicochemical properties and preparation methods of natural melanin and melanin-like nanoparticles were outlined. A systematical description of the recent progress of melanin and melanin-like nanoparticles in single, dual-, and tri-multimodal imaging-guided the visual administration and treatment of osteoarthritis, acute liver injury, acute kidney injury, acute lung injury, brain injury, periodontitis, iron overload, etc. Was then given. Finally, it concluded with a reasoned discussion of current challenges toward clinical translation and future striving directions. Therefore, this comprehensive review provides insight into the current status of melanin and melanin-like nanoparticles research and is expected to optimize the design of novel melanin-based therapeutic platforms and further clinical translation.

Effective magnetic hyperthermia induced by mitochondria-targeted nanoparticles modified with triphenylphosphonium-containing phospholipid polymers

Magnetic hyperthermia (MHT) is a promising cancer treatment because tumor tissue can be specifically damaged by utilizing the heat generated by nano-heaters such as magnetite nanoparticles (MNPs) under an alternating magnetic field. MNPs are taken up by cancer cells, enabling intracellular MHT. Subcellular localization of MNPs can affect the efficiency of intracellular MHT. In this study, we attempted to improve the therapeutic efficacy of MHT by using mitochondria-targeting MNPs. Mitochondria-targeting MNPs were prepared by the modification of carboxyl phospholipid polymers containing triphenylphosphonium (TPP) moieties that accumulate in mitochondria. The mitochondrial localization of polymer-modified MNPs was supported by transmission electron microscopy observations of murine colon cancer CT26 cells treated with polymer-modified MNPs. In vitro and in vivo MHT using polymer-modified MNPs revealed that the therapeutic effects were enhanced by introducing TPP. Our results indicate the validity of mitochondria targeting in enhancing the therapeutic outcome of MHT. These findings will pave the way for developing a new strategy for the surface design of MNPs and therapeutic strategies for MHT.

Activatable Immunoprotease Nanorestimulator for Second Near-Infrared Photothermal Immunotherapy of Cancer

Photothermal immunotherapy is a combinational cancer therapy modality, wherein the photothermal process can noninvasively ablate cancer and efficiently trigger cancer immunogenic cell death to ignite antitumor immunity. However, cancer cells can resist the cytotoxic lymphocyte-mediated antitumor effect via expressing serine protease inhibitory proteins (serpins) to deactivate proteolytic immunoproteases. Herein, we report a smart polymer nanoagonist (SPND) with second near-infrared (NIR-II) phototherapeutic ablation and tumor-specific immunoprotease granzyme B (GrB) restimulation for cancer photothermal immunotherapy. SPND has a semiconducting polymer backbone grafted with a small-molecule inhibitor of serpinB9 (Sb9i) via a glutathione (GSH)-cleavable linker. Once in the tumor, Sb9i can be specifically liberated from SPND to inhibit serpinB9, restimulating the activity of GrB to enhance cancer immunotherapy. Moreover, SPND induces photothermal therapy for direct tumor ablation and immunogenic cancer cell death (ICD) under NIR-II photoirradiation. Therefore, such a smart nanoagonist represents a way toward combination photothermal immunotherapy (PTI).

NIR-II-absorbing diimmonium polymer agent achieves excellent photothermal therapy with induction of tumor immunogenic cell death

Photothermal therapy has shown great promise for cancer treatment and second near-infrared (NIR-II) -absorbing particles could further improve its precision and applicability due to its superior penetration depth and new imaging ability. Herein, high NIR-II-absorbing polymer particles were prepared by using soluble isobutyl-substituted diammonium borates (P-IDI). The P-IDI showed stronger absorption at 1000-1100 nm, which exhibited excellent photostability, strong photoacoustic imaging ability and high photothermal conversion efficiency (34.7%). The investigations in vitro and in vivo demonstrated that the excellent photothermal effect facilitated complete tumor ablation and also triggered immunogenic cell death in activation of the immune response. The high solubility and excellent photothermal conversion ability demonstrated that polymer IDI particles were promising theranostic agents for treatment of tumors with minor side effects.

NIR-II Light-Activated Gold Nanorods for Synergistic Thermodynamic and Photothermal Therapy of Tumor

There are tricky challenges in tumor therapy due to the hypoxic tumor microenvironment, inevitably inhibiting the treatment efficacy of the traditional photodynamic therapy (PDT), radiation therapy (RT), and sonodynamic therapy (SDT). Herein, to overcome tumor hypoxia limitation, we constructed a near-infrared II (NIR-II) light-triggered thermodynamic therapy (TDT) nanoplatform of Au@mSiO₂-AIPH@PCM/PEG (ASAPP) by integrating the Au nanorods (Au NRs) and thermally activated alkyl free radical-releasing molecules (AIPH). Au NRs@mSiO₂ was used as a photothermally responsive material and AIPH carrier, and the hot-melt phase-change material (PCM) was used as a capping agent to prevent leakage of AIPH during blood circulation. Upon NIR-II light irradiation, heat-triggered free radical release from AIPH was successfully achieved for killing cancer cells in vitro and in vivo without oxygen dependence, leading to synergistically enhanced antitumor therapy.

Nanoparticles-based phototherapy systems for cancer treatment: Current status and clinical potential

Remarkable progress in phototherapy has been made in recent decades, due to its non-invasiveness and instant therapeutic efficacy. In addition, with the rapid development of nanoscience and nanotechnology, phototherapy systems based on nanoparticles or nanocomposites also evolved as an emerging hotspot in nanomedicine research, especially in cancer. In this review, first we briefly introduce the history of phototherapy, and the mechanisms of phototherapy in cancer treatment. Then, we summarize the representative development over the past three to five years in nanoparticle-based phototherapy and highlight the design of the innovative nanoparticles thereof. Finally, we discuss the feasibility and the potential of the nanoparticle-based phototherapy systems in clinical anticancer therapeutic applications, aiming to predict future research directions in this field. Our review is a tutorial work, aiming at providing useful insights to researchers in the field of nanotechnology, nanoscience and cancer.

Recent Advances in Engineering Nanomedicines for Second Near-Infrared Photothermal-Combinational Immunotherapy

Immunotherapy has emerged as one of the major strategies for cancer treatment. Unlike conventional therapeutic methods, immunotherapy can treat both primary and distant metastatic tumors through triggering systematic antitumor immune responses and can even prevent tumor recurrence after causing the formation of immune memory. However, immunotherapy still has the issues of low patient response rates and severe immune-related adverse events in clinical practices. In this regard, the combination of nanomedicine-mediated therapy with immunotherapy can modulate a tumor immunosuppressive microenvironment and thus amplify antitumor immunity. In particular, second near-infrared (NIR-II) photothermal therapy (PTT), which utilizes light conversions to generate heat for killing cancer cells, has shown unique advantages in combining with immunotherapy. In this review, the recent progress of engineering nanomedicines for NIR-II PTT combinational immunotherapy is summarized. The role of nanomedicine-mediated NIR-II PTT in inducing immunogenic cell death and reprogramming the tumor immunosuppressive microenvironment for facilitating immunotherapy are highlighted. The development of NIR-II-absorbing organic and inorganic nonmetal and inorganic metal nanomedicines for the NIR-II PTT combinational immunotherapy of cancer is also introduced in detail. Lastly, the current challenges and future perspectives of these nanomedicines for combinational immunotherapy are proposed.