Dynamic Effects of Endo-Exogenous Stimulations on Enzyme-Activatable Polymeric Nanosystems with Photo-Sono-Chemo Synergy

TADF-Guiding Modification of Endoplasmic Reticulum-Targeted Photosensitizers for Efficient Photodynamic Immunotherapy

Pharmacological activation of the immunogenic cell death (ICD) pathway by endoplasmic reticulum (ER) targeted photosensitizer (PS) has become a promising strategy for tumor immunotherapy. Despite a clear demand for ER-targeted PS, the sluggish intersystem crossing (ISC) process, unstable excited state, insufficient ROS production, and immunosuppressive tumor microenvironment (ITME) combined to cause the high-efficiency agents are still limited. Herein, three groups commonly used in thermally activated delayed fluorescence (TADF) molecular design are used to modify the excited state characteristics of xanthene-based cyanine PS (obtained the XCy-based PS). The electronic and geometric modulation effectively optimize the excited state characteristics, facilitating the ISC process and prolonging the excited state life for boosting ROS generation. Among them, car-XCy showed 100 times longer excited state life and 225% higher ROS yield than that of original XCy. The satisfactory ROS production and ER-targeted ability of car-XCy arouse intense ER stress to activate the ICD. Adequate antigen presentation promotes the dendritic cell maturation and infiltration of cytotoxic T lymphocytes (CTLs), ultimately reversing the ITME to realize efficient immunotherapy. As a result, significant inhibition is observed in both primary and distant tumors, underscoring the efficacy of this TADF-guiding excited state characteristics modulation strategy for developing photodynamic immunotherapy drugs.

Triangle-toothed gear occlude-guided universal nanotechnology constructs 3D symmetric DNA polyhedra with high assembly efficiency for precision cancer therapy

Chemotherapy is commonly used to treat malignant tumors. However, conventional chemotherapeutic drugs often cannot distinguish between tumor and healthy cells, resulting in adverse effects and reduced therapeutic efficacy. Therefore, zigzag-shaped gear-occlude-guided cymbal-closing (ZGC) DNA nanotechnology was developed based on the mirror-symmetry principle to efficiently construct symmetric DNA polyhedra. This nanotechnology employed simple mixing steps for efficient sequence design and assembly. A targeting aptamer was installed at a user-defined position using an octahedron as a model structure. Chemotherapeutic drug-loaded polyhedral objects were subsequently delivered into tumor cells. Furthermore, anticancer drug-loaded DNA octahedra were intravenously injected into a HeLa tumor-bearing mouse model. Assembly efficiency was almost 100 %, with no residual building blocks identified. Moreover, this nanotechnology required a few DNA oligonucleotides, even for complex polyhedrons. Symmetric DNA polyhedrons retained their structural integrity for 24 h in complex biological environments, guaranteeing prolonged circulation without drug leakage in the bloodstream and promoting efficient accumulation in tumor tissues. In addition, DNA octahedra were cleared relatively slowly from tumor tissues. Similarly, tumor growth was significantly inhibited in vivo, and a therapeutic outcome comparable to that of conventional gene-chemo combination therapy was observed. Moreover, no systemic toxicity was detected. These findings indicate the potential application of ZGC DNA nanotechnology in precision medicine.

DNA nanodevice as a multi-module co-delivery platform for combination cancer immunotherapy

A major challenge in combining cancer immunotherapy is the efficient delivery of multiple types of immunological stimulators to elicit a robust anti-tumor immune response and reprogram the immunosuppressive tumor microenvironment (TME). Here, we developed a DNA nanodevice that was generated by precisely assembling three types of immunological stimulators. The doxorubicin (Dox) component induced immunogenic cell death (ICD) in tumor cells and enhanced phagocytosis of antigen-presenting cells (APCs). Exogenous double-stranded DNA (dsDNA) could act as a molecular adjuvant to activate the stimulator of interferon genes (STING) signaling in APCs by engulfing dying tumor cells. Interleukin (IL)-12 and small hairpin programmed cell death-ligand 1 (shPD-L1) transcription templates were designed to regulate TME. Additionally, for targeted drug delivery, multiple cyclo[Arg-Gly-Asp-(d-Phe)-Cys] (cRGD) peptide units on DNA origami were employed. The incorporation of disulfide bonds allowed the release of multiple modules in response to intracellular glutathione (GSH) in tumors. The nanodevice promoted the infiltration of CD8+ and CD4+ cells into the tumor and generated a highly inflamed TME, thereby enhancing the effectiveness of cancer immunotherapy. Our research results indicate that the nanodevice we constructed can effectively inhibit tumor growth and prevent lung metastasis without obvious systemic toxicity, providing a promising strategy for cancer combination treatment.

Mild phototherapy mediated by IR780-Gd-OPN nanomicelles suppresses atherosclerotic plaque progression through the activation of the HSP27-regulated NF-κB pathway

Reducing plaque lipid content and enhancing plaque stability without causing extensive apoptosis of foam cells are ideal requirements for developing a safe and effective treatment of atherosclerosis. In this study, we synthesized IR780-Gd-OPN nanomicelles by conjugating osteopontin (OPN) and loading a gadolinium-macrocyclic ligand (Gd-DOTA) onto near-infrared dye IR780-polyethylene glycol polymer. The nanomicelles were employed for mild phototherapy of atherosclerotic plaques and dual-mode imaging with near-infrared fluorescence and magnetic resonance. In vitro results reveal that the mild phototherapy mediated by IR780-Gd-OPN nanomicelles not only activates heat shock protein (HSP) 27 to protect foam cells against apoptosis but also inhibits the nuclear factor kappa-B (NF-κB) pathway to regulate lipid metabolism and macrophage polarization, thereby diminishing the inflammatory response. In vivo results further validate that mild phototherapy effectively reduces plaque lipid content and size while simultaneously enhancing plaque stability by regulating the ratio of M1 and M2-type macrophages. In summary, this study presents a promising approach for developing a safe and highly efficient method for the precise therapeutic visualization of atherosclerosis. STATEMENT OF SIGNIFICANCE: The rupture of unstable atherosclerotic plaques is a major cause of high mortality rates in cardiovascular diseases. Therefore, the ideal outcome of atherosclerosis treatment is to reduce plaque size while enhancing plaque stability. To address this challenge, we designed IR780-Gd-OPN nanomicelles for mild phototherapy of atherosclerosis. This treatment can effectively reduce plaque size while significantly improving plaque stability by increasing collagen fiber content and elevating the ratio of M2/M1 macrophages, which is mainly attributed to the inhibition of the NF-κB signaling pathway by mild phototherapy-activated HSP27. In summary, our proposed mild phototherapy strategy provides a promising approach for safe and effective treatment of atherosclerosis.

Blocking the utilization of carbon sources via two pathways to induce tumor starvation for cancer treatment

Glucose oxidase (GOx) is often used to starvation therapy. However, only consuming glucose cannot completely block the energy metabolism of tumor cells. Lactate can support tumor cell survival in the absence of glucose. Here, we constructed a nanoplatform (Met@HMnO2-GOx/HA) that can deplete glucose while inhibiting the compensatory use of lactate by cells to enhance the effect of tumor starvation therapy. GOx can catalyze glucose into gluconic acid and H2O2, and then HMnO2 catalyzes H2O2 into O2 to compensate for the oxygen consumed by GOx, allowing the reaction to proceed sustainably. Furthermore, metformin (Met) can inhibit the conversion of lactate to pyruvate in a redox-dependent manner and reduce the utilization of lactate by tumor cells. Met@HMnO2-GOx/HA nanoparticles maximize the efficacy of tumor starvation therapy by simultaneously inhibiting cellular utilization of two carbon sources. Therefore, this platform is expected to provide new strategies for tumor treatment.

Theranostic Fluorescent Probes

The ability to gain spatiotemporal information, and in some cases achieve spatiotemporal control, in the context of drug delivery makes theranostic fluorescent probes an attractive and intensely investigated research topic. This interest is reflected in the steep rise in publications on the topic that have appeared over the past decade. Theranostic fluorescent probes, in their various incarnations, generally comprise a fluorophore linked to a masked drug, in which the drug is released as the result of certain stimuli, with both intrinsic and extrinsic stimuli being reported. This release is then signaled by the emergence of a fluorescent signal. Importantly, the use of appropriate fluorophores has enabled not only this emerging fluorescence as a spatiotemporal marker for drug delivery but also has provided modalities useful in photodynamic, photothermal, and sonodynamic therapeutic applications. In this review we highlight recent work on theranostic fluorescent probes with a particular focus on probes that are activated in tumor microenvironments. We also summarize efforts to develop probes for other applications, such as neurodegenerative diseases and antibacterials. This review celebrates the diversity of designs reported to date, from discrete small-molecule systems to nanomaterials. Our aim is to provide insights into the potential clinical impact of this still-emerging research direction.

Defect-rich platinum-zinc oxide heterojunction as a potent ROS amplifier for synergistic sono-catalytic therapy

Sonodynamic therapy (SDT) is a physical therapy that utilizes critical sonosensitizers triggered by ultrasound to achieve an effective non-invasive tumor treatment. However, the inadequate sonodynamic efficacy and low responsive activities of traditional inorganic sonosensitizers have hindered its practical application. Here, we rationally design a platinum-zinc oxide (PtZnO) sonosensitizer to significantly enhance the efficacy of SDT through its inherent bandgap structure and dual-nanozyme activities. The PtZnO possesses a narrow bandgap (2.89 eV) and an appropriate amount of oxygen defects, which promote the efficiency of electrons and holes separation and the generation of reactive oxygen species (ROS) under US irradiation. Simultaneously, the PtZnO exhibits both catalase-like and peroxidase-like activities, which effectively catalyze endogenous H2O2 into a large number of O2 and toxic hydroxyl radicals (•OH), thus achieving an efficient enhancement of SDT and catalytic therapy. Moreover, the PtZnO has significant glutathione consumption performance, further amplifying the oxidative stress. Ultimately, the PtZnO achieves a triple ROS amplification effect, with the yields of singlet oxygen (1O2) and •OH reaching 859.1 % and 614.4 %, respectively, inducing a highly effective sono-catalytic therapy with a remarkable tumor inhibition rate of 98.1 %. This study expands the application of ZnO semiconductor heterojunctions in the nanomedicine area, and the simple yet efficient design of the PtZnO provides a strategy for the development of sonosensitizers. STATEMENT OF SIGNIFICANCE: A platinum-zinc oxide (PtZnO) heterojunction sonosensitizer is constructed with dual-nanozyme activities and achieves a triple ROS amplification effect, leading to an efficient synergistic sono-catalytic therapy. The PtZnO owns an inherent narrow bandgap and abundant oxygen defects, thus exhibiting an efficient sonosensitizer performance. It also possesses both catalase-like and peroxidase-like activities, which effectively catalyze the endogenous H2O2 into a large quantity of O2 and toxic hydroxyl radicals, thereby enhancing the SDT and catalytic therapy. Furthermore, its prominent glutathione consumption performance further amplifies oxidative stress. The yields of singlet oxygen and hydroxyl radicals reach up to 859.1 % and 614.4 %, respectively, inducing a highly effective sono-catalytic therapy with an impressive tumor inhibition rate of 98.1 %.

Doxorubicin prodrug-based nanomedicines for the treatment of cancer

The chemotherapeutic drug of doxorubicin (DOX) has witnessed widespread applications for treating various cancers. DOX-treated dying cells bear cellular modifications which allow enhanced presentation of tumor antigen and neighboring dendritic cell activation. Furthermore, DOX also facilitate the immune-mediated clearance of tumor cells. However, disadvantages such as severe off-target toxicity, and prominent hydrophobicity have resulted in unsatisfactory clinical therapeutic outcomes. The effective delivery of DOX drug molecules is still challenging despite the rapid advances in nanotechnology and biomaterials. Huge progress has been witnessed in DOX nanoprodrugs owing to their brilliant benefits such as tumor stimuli-responsive drug release capacity, high drug loading efficiency and so on. This review summarized recent progresses of DOX prodrug-based nanomedicines to provide deep insights into future development and inspire researchers to explore DOX nanoprodrugs with real clinical applications.

Design and synthesis of cancer-cell-membrane-camouflaged hemoporfin-Cu9S8 nanoagents for homotypic tumor-targeted photothermal-sonodynamic therapy

Multimodal therapies have aroused great interest in tumor therapy due to their highly effective antitumor effect. However, immune clearance limits the practical application of nanoagents-based multimodal therapies. To solve this problem, we have designed hemoporfin-Cu₉S₈ hollow nanospheres camouflaged with the CT26 cell membrane (CCM) as a model of multifunctional agents, achieving homologous-targeted synergistic photothermal therapy (PTT) and sonodynamic therapy (SDT). Hollow Cu₉S₈ as photothermal agents and carriers have been obtained through sulfurizing cuprous oxide (Cu₂O) nanoparticles through "Kirkendall effect", and they exhibit hollow nanospheres structure with a size of ∼200 nm. Then, Cu₉S₈ nanospheres could be used to load with hemoporfin sonosensitizers, and then hemoporfin-Cu₉S₈ nanospheres (abbreviated as H-Cu₉S₈) can be further surface-camouflaged with CCM. H-Cu₉S₈@CCM nanospheres exhibit a broad photoabsorption in the range of 700-1100 nm and high photothermal conversion efficiency of 39.8% under 1064 nm laser irradiation for subsequent PTT. In addition, under the excitation of ultrasound, the loaded hemoporfin could generate ¹O₂ for subsequent SDT. Especially, H-Cu₉S₈@CCM NPs are featured with biocompatibility and homologous targeting capacity. When intravenously (i.v.) injected into mice, H-Cu₉S₈@CCM NPs display a higher blood circulation half-life (3.17 h, 6.47 times) and tumor accumulation amount (18.75% ID/g, 1.94 times), compared to H-Cu₉S₈ NPs (0.49 h, 9.68% ID/g) without CCM. In addition, upon 1064 nm laser and ultrasound irradiation, H-Cu₉S₈@CCM NPs can inhibit tumor growth more efficiently due to high accumulation efficiency and synergistic PTT-SDT functions. Therefore, the present study provides some insight into the design of multifunctional efficient agents for homotypic tumor-targeted therapy.

Two-dimensional-Ti3C2 magnetic nanocomposite for targeted cancer chemotherapy

Introduction: Cervical cancer is the leading cause of cancer-related death in women, so novel therapeutic approaches are needed to improve the effectiveness of current therapies or extend their activity. In recent decades, graphene analogs, such as Mxene, an emerging class of two-dimensional (2D) graphene analogs, have been drawing considerable attention based on their intrinsic physicochemical properties and performance as potential candidates for tumor therapy, particularly for therapeutic purposes. Here we explored the targeted drug delivery in cervical cancer in in vivo model. Mxene-based nanocarriers are not able to be precisely controlled in cancer treatment. Method: To solve this problem, the titanium carbide-magnetic core-shell nanocarrier (Ti₃C₂-Fe₃O₄@SiO₂-FA) is also developed to provide synergetic anticancer with magnetic controlling ability along with pH-responsive drug release. A xenograft model of the cervix was used to investigate the effects of Cisplatin alone, or in combination with Ti₃C₂@FA and Ti₃C₂@ Fe₃O₄@SiO₂-FA, on tumor growth following histological staining for evaluation of necrosis. Result and Discussion: A significant tumor-growth suppression effect is shown when the Ti₃C₂-Fe₃O₄@SiO₂-FA nanocarrier is magnetically controlled Cisplatin drug release. It reveals a synergistic therapeutic efficacy used in conjunction with pharmaceuticals (p < .001). According to the in vivo study, the Ti₃C₂@FA@Cisplatin nanocomposite exhibits less tumor growth than the drug alone or Ti₃C₂@FA@Cisplatin via increasing necrosis effect (p < .001). Through this study, Mxene nanosheets are expanded for biomedical applications, not only through the fabrication of biocompatible magnetic Mxene nanocomposite but also through the development of functionalization strategies that enable the magnetic Ti₃C₂ nanocomposite to load high levels of Cisplatin for cervical cancer treatment (242.5%). Hence, Ti₃C₂-Fe₃O₄@SiO₂-FA nanocarriers would be promising candidates to improve cancer treatment efficiency.

DEB-TACE with irinotecan versus C-TACE for unresectable intrahepatic cholangiocarcinoma: a prospective clinical study

Objectives: DEB-TACE with irinotecan and C-TACE were compared with regards to safety and efficacy for the therapy of intrahepatic cholangiocarcinoma (ICC). Methods: Institutional Review Board approved our trial and we registered it in the Chinese Clinical Trial Registry (ChiCTR1900022856). Forty patients with biopsy-confirmed ICC were randomised to either receive DEB-TACE or C-TACE treatment with 20 patients in each treatment arm. The primary endpoints objective response rate (ORR) and progression free survival (PFS) using the mRECIST to evaluate the tumours. The secondary endpoints were overall survival (OS) and safety. The chi-square was used to analyse the data. The Kaplan-Meier method and Cox analysis were used to evaluate the survival data. Results: ORR (70% in DEB-TACE group vs. 20% in C-TACE, p = .001) at 1 month after therapy, ORR (50% vs. 15%, p = .018) at 3 months and DCR (70% vs. 30%, p = .011) at 6 months, while no difference was found in other groups. (all p > .05) The median PFS with DEB-TACE was longer than that with C-TACE (8.0 months vs. 3.0 months) (p = .042). Although the median OS was longer with DEB-TACE than with C-TACE (11.5 months vs. 9.0 months), the difference was not statistically significant (p = .280). The Cox regression analysis demonstrated that TACE sessions (p = .017) and low CA125 levels (p = .001) were independent favourable prognostic factors. The most frequent adverse event was elevated transaminase levels (20/20 in DEB-TACE group vs. 15/20 in C-TACE group) (p = .047). Conclusion: Our prospective study suggested better ORR and PFS with DEB-TACE with irinotecan as compared to C-TACE with irinotecan in the treatment of unresectable ICC.

Polyethyleneimine-Based Drug Delivery Systems for Cancer Theranostics

With the development of nanotechnology, various types of polymer-based drug delivery systems have been designed for biomedical applications. Polymer-based drug delivery systems with desirable biocompatibility can be efficiently delivered to tumor sites with passive or targeted effects and combined with other therapeutic and imaging agents for cancer theranostics. As an effective vehicle for drug and gene delivery, polyethyleneimine (PEI) has been extensively studied due to its rich surface amines and excellent water solubility. In this work, we summarize the surface modifications of PEI to enhance biocompatibility and functionalization. Additionally, the synthesis of PEI-based nanoparticles is discussed. We further review the applications of PEI-based drug delivery systems in cancer treatment, cancer imaging, and cancer theranostics. Finally, we thoroughly consider the outlook and challenges relating to PEI-based drug delivery systems.

A facile synthesis of PEGylated Cu2O@SiO2/MnO2 nanocomposite as efficient photo−Fenton−like catalysts for methylene blue treatment

The removal of toxic organic dyes from wastewater has received much attention from the perspective of environmental protection. Metal oxides see wide use in pollutant degradation due to their chemical stability, low cost, and broader light absorption spectrum. In this work, a Cu2O−centered nanocomposite Cu2O@SiO2/MnO2−PEG with an average diameter of 52 nm was prepared for the first time via a wet chemical route. In addition, highly dispersed MnO2 particles and PEG modification were realized simultaneously in one step, meanwhile, Cu2O was successfully protected under a dense SiO2 shell against oxidation. The obtained Cu2O@SiO2/MnO2−PEG showed excellent and stable photo−Fenton−like catalytic activity, attributed to integration of visible light−responsive Cu2O and H2O2−responsive MnO2. A degradation rate of 92.5% and a rate constant of 0.086 min−1 were obtained for methylene blue (MB) degradation in the presence of H2O2 under visible light for 30 min. Additionally, large amounts of •OH and 1O2 species played active roles in MB degradation. Considering the enhanced degradation of MB, this stable composite provides an efficient catalytic system for the selective removal of organic contaminants in wastewater.