Nanoarchitectonic Engineering of Thermal-Responsive Magnetic Nanorobot Collectives for Intracranial Aneurysm Therapy.

Stent-assisted coiling is a main treatment modality for intracranial aneurysms (IAs) in clinics, but critical challenges remain to be overcome, such as exogenous implant-induced stenosis and reliance on antiplatelet agents. Herein, an endovascular approach is reported for IA therapy without stent grafting or microcatheter shaping, enabled by active delivery of thrombin (Th) to target aneurysms using innovative phase-change material (PCM)-coated magnetite-thrombin (Fe3O4-Th@PCM) FTP nanorobots. The nanorobots are controlled by an integrated actuation system of dynamic torque-force hybrid magnetic fields. With robust intravascular navigation guided by real-time ultrasound imaging, nanorobotic collectives can effectively accumulate and retain in model aneurysms constructed in vivo, followed by controlled release of the encapsulated Th for rapid occlusion of the aneurysm upon melting the protective PCM (thermally responsive in a tunable manner) through focused magnetic hyperthermia. Complete and stable aneurysm embolization is confirmed by postoperative examination and 2-week postembolization follow-up using digital subtraction angiography (DSA), contrast-enhanced ultrasound (CEUS), and histological analysis. The safety of the embolization therapy is assessed through biocompatibility evaluation and histopathology assays. This strategy, seamlessly integrating secure drug packaging, agile magnetic actuation, and clinical interventional imaging, avoids possible exogenous implant rejection, circumvents cumbersome microcatheter shaping, and offers a promising option for IA therapy.

Self-synergistic effect of Prussian blue nanoparticles for cancer therapy: driving photothermal therapy and reducing hyperthermia-induced side effects.

BACKGROUND: Photothermal therapy (PTT), involving application of localized hyperthermia to kill cancer cells, has attracted wide attention in cancer therapy. The production of reactive oxygen species (ROS) during PTT may cause irreversible damage to healthy tissues around the tumor. Simultaneously, hyperthermia can stimulate inflammatory response, thus promoting tumor recurrence and metastasis. Therefore, it is of paramount importance to reduce the undesired side effects for further development of PTT. RESULTS: Using a hydrothermal method, spherical Prussian blue nanoparticles (PBs) with uniform size were prepared. The PBs exhibited good dispersion and stability in saline with an average hydrodynamic size of 110 nm. The prepared PBs had a high photothermal conversion efficiency and photothermal stability. The PBs showed intrinsic ROS scavenging properties in vitro. Antioxidant and anti-inflammatory effects of PBs were also observed in vivo. Assessment of toxicity and endoplasmic reticulum stress-inducing ability showed that PBs did not induce an inflammatory response. Tissues of major organs of mice stained with hematoxylin-eosin showed no significant damage, indicating good biocompatibility and safety of PBs. CONCLUSION: The designed single-component PBs with intrinsic ROS scavenging and anti-inflammatory properties could avoid inflammatory response and heat stress-induced ROS during PTT. Thus, further research on PBs is worthwhile to achieve their clinical translation and promote the development of PTT.

Biodegradable reduce expenditure bioreactor for augmented sonodynamic therapy via regulating tumor hypoxia and inducing pro-death autophagy.

BACKGROUNDS: Sonodynamic therapy (SDT) as an emerging reactive oxygen species (ROS)-mediated antitumor strategy is challenged by the rapid depletion of oxygen, as well as the hypoxic tumor microenvironment. Instead of the presently available coping strategies that amplify the endogenous O2 level, we have proposed a biodegradable O2 economizer to reduce expenditure for augmenting SDT efficacy in the present study. RESULTS: We successfully fabricated the O2 economizer (HMME@HMONs-3BP-PEG, HHBP) via conjugation of respiration inhibitor 3-bromopyruvate (3BP) with hollow mesoporous organosilica nanoparticles (HMONs), followed by the loading of organic sonosensitizers (hematoporphyrin monomethyl ether; HMME) and further surface modification of poly(ethylene glycol) (PEG). The engineered HHBP features controllable pH/GSH/US-sensitive drug release. The exposed 3BP could effectively inhibit cell respiration for restraining the oxygen consumption, which could alleviate the tumor hypoxia conditions. More interestingly, it could exorbitantly elevate the autophagy level, which in turn induced excessive activation of autophagy for promoting the therapeutic efficacy. As a result, when accompanied with suppressing O2-consumption and triggering pro-death autophagy strategy, the HHBP could achieve the remarkable antitumor activity, which was systematically validated both in vivo and in vitro assays. CONCLUSIONS: This work not only provides a reduce expenditure means for enduring SDT, but also represents an inquisitive strategy for tumor treatments by inducing pro-death autophagy.

Neutrophil-mediated clinical nanodrug for treatment of residual tumor after focused ultrasound ablation.

BACKGROUND: The risk of local recurrence after high-intensity focused ultrasound (HIFU) is relatively high, resulting in poor prognosis of malignant tumors. The combination of HIFU with traditional chemotherapy continues to have an unsatisfactory outcome because of off-site drug uptake. RESULTS: Herein, we propose a strategy of inflammation-tendency neutrophil-mediated clinical nanodrug targeted therapy for residual tumors after HIFU ablation. We selected neutrophils as carriers and PEGylated liposome doxorubicin (PLD) as a model chemotherapeutic nanodrug to form an innovative cell therapy drug (PLD@NEs). The produced PLD@NEs had a loading capacity of approximately 5 µg of PLD per 106 cells and maintained the natural characteristics of neutrophils. The targeting performance and therapeutic potential of PLD@NEs were evaluated using Hepa1-6 cells and a corresponding tumor-bearing mouse model. After HIFU ablation, PLD@NEs were recruited to the tumor site by inflammation (most in 4 h) and released PLD with inflammatory stimuli, leading to targeted and localized postoperative chemotherapy. CONCLUSIONS: This effective integrated method fully leverages the advantages of HIFU, chemotherapy and neutrophils to attract more focus on the practice of improving existing clinical therapies.

Self-supplying Cu2+ and H2O2 synergistically enhancing disulfiram-mediated melanoma chemotherapy.

Disulfiram (DSF) can target and kill cancer cells by disrupting cellular degradation of extruded proteins and has therefore received particular attention for its tumor chemotherapeutic potential. However, the uncontrollable Cu2+/DSF ratio reduces the efficacy of DSF-mediated chemotherapy. Herein, self-supplying Cu2+ and oxidative stress synergistically enhanced DSF-mediated chemotherapy is proposed for melanoma-based on PVP-coated CuO2 nanodots (CPNDs). Once ingested, DSF is broken down to diethyldithiocarbamate (DTC), which is delivered into a tumor via the circulation. Under the acidic tumor microenvironment, CPNDs produce sufficient Cu2+ and H2O2. DTC readily chelates Cu2+ ions to generate CuET, which shows antitumor efficacy. CuET-mediated chemotherapy can be enhanced by H2O2. Sufficient Cu2+ generation can guarantee the maximum efficacy of DSF-mediated chemotherapy. Furthermore, released Cu2+ can be reduced to Cu+ by glutathione (GSH) and O2- in tumor cells, and Cu+ can react with H2O2 to generate toxic hydroxyl radicals (·OH) via a Fenton-like reaction, promoting the efficacy of CuET. Therefore, this study hypothesizes that employing CPNDs instead of Cu2+ ions could enhance DSF-mediated melanoma chemotherapy, providing a simple but efficient strategy for achieving chemotherapeutic efficacy.

Prussian Blue Nanozyme as a Pyroptosis Inhibitor Alleviates Neurodegeneration.

Current pharmacological interventions for Parkinson's disease (PD) remain unsatisfactory in clinical settings. Inflammasome-mediated pyroptosis represents a potential therapeutic target for the alleviation of neurodegenerative diseases. The development of inflammasome-mediated pyroptosis agonists or antagonists may transform the treatment of neurodegenerative diseases. However, the identification of specific compounds that inhibit pyroptosis remains challenging. Herein, Prussian blue nanozyme (PBzyme) is revealed as a pyroptosis inhibitor to alleviate the neurodegeneration in mouse and cell models of PD. PBzyme protects the microglia and neurons against 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). PBzyme alleviates motor deficits, attenuates the damage of mitochondrial membrane potential, and rescues dopaminergic neurons. Furthermore, intra-cerebroventricular injection of PBzyme reduces dopaminergic degeneration and inhibits neuroinflammation in an MPTP-induced PD mouse model. Both in vitro and in vivo results demonstrate that PBzyme reduces the activation of microglial nucleotide-binding domain and leucine-rich repeat family pyrin domain containing 3 (NLRP3) inflammasomes and caspase-1 by scavenging reactive oxygen species, thereby downregulating gasdermin D (GSDMD) cleavage as well as inflammatory factor production, and eventually leading to the inhibition of microglia pyroptosis. Overall, this work highlights the neuroprotective effects of PBzyme as a pyroptosis inhibitor and provides valuable mechanistic insights and a potential therapeutic strategy for the treatment of PD.

Guiding Drug Through Interrupted Bloodstream for Potentiated Thrombolysis by C-Shaped Magnetic Actuation System In Vivo.

Fast and effective thrombolysis using tissue plasminogen activator (tPA) is limited by the poor delivery efficiency of thrombolytic drugs, which is induced by an interrupted bloodstream and delayed recanalization. Existing magnetic micro/nanodrug-loaded robots used for targeted thrombotic therapy are limited by the complexity of the clinical verification of nanodrugs and the limited space of magnetic actuation systems. Herein, a general drug delivery strategy based on mass transportation theory for thrombolysis is presented, and an open space C-shaped magnetic actuation system with laser location and ultrasound imaging navigation for in vivo evaluation is developed. tPA can be guided through an interrupted bloodstream to the thrombi by the locomotion of magnetic nanoparticle swarms (MNSs), thereby improving the thrombolysis efficacy. Notably, this strategy is able to quickly establish a life channel to achieve time-critical recanalization, which is typically inaccessible using native tPA. Both in vitro and in vivo thrombolysis experiments demonstrate that the thrombus lysis efficacy significantly increases after the application of the MNS under a rotating magnetic field. This study provides an anticipated C-shaped magnetic actuation system for in vivo validation and also presents a clinically feasible drug delivery strategy for targeted thrombolytic therapy with minimal systemic tPA exposure.

Combined Magnetic Hyperthermia and Immune Therapy for Primary and Metastatic Tumor Treatments.

Cancer immunotherapy shows promising potential in future cancer treatment but unfortunately is clinically unsatisfactory due to the low therapeutic efficacy and the possible severe immunotoxicity. Here we show a combined magnetic hyperthermia therapy (MHT) and checkpoint blockade immunotherapy for both primary tumor ablation and mimetic metastatic tumor inhibition. Monodispersed, high-performance superparamagnetic CoFe2O4@MnFe2O4 nanoparticles were synthesized and used for effective MHT-induced thermal ablation of primary tumors. Simultaneously, numerous tumor-associated antigens were produced to promote the maturation and activation of dendritic cells (DCs) and cytotoxic T cells for effective immunotherapy of distant mimetic metastatic tumors in a tumor-bearing mice model. The combined MHT and checkpoint blockade immunotherapy demonstrate the great potentials in the fight against both primary and metastatic tumors.

Mesoporous composite nanoparticles for dual-modality ultrasound/magnetic resonance imaging and synergistic chemo-/thermotherapy against deep tumors.

High-intensity focused ultrasound (HIFU) is a promising and noninvasive treatment for solid tumors, which has been explored for potential clinical applications. However, the clinical applications of HIFU for large and deep tumors such as hepatocellular carcinoma (HCC) are severely limited by unsatisfactory imaging guidance, long therapeutic times, and damage to normal tissue around the tumor due to the high power applied. In this study, we developed doxorubicin/perfluorohexane-encapsulated hollow mesoporous Prussian blue nanoparticles (HMPBs-DOX/PFH) as theranostic agents, which can effectively guide HIFU therapy and enhance its therapeutic effects in combination with chemotherapy, by decreasing the cavitation threshold. We investigated the effects of this agent on ultrasound and magnetic resonance imaging in vitro and in vivo. In addition, we showed a highly efficient HIFU therapeutic effect against HCC tumors, as well as controlled drug release, owing to the phase-transitional performance of the PFH. We therefore conclude that HMPB-DOX/PFH is a safe and efficient nanoplatform, which holds significant promise for cancer theranostics against deep tumors in clinical settings.