Nebulized Therapy of Early Orthotopic Lung Cancer by Iron-Based Nanoparticles: Macrophage-Regulated Ferroptosis of Cancer Stem Cells.

Cancer stem cells (CSCs) within protumorigenic microlesions are a critical driver in the initiation and progression of early stage lung cancer, where immune cells provide an immunosuppressive niche to strengthen the CSC stemness. As the mutual interactions between CSCs and immune cells are increasingly recognized, regulating the immune cells to identify and effectively eliminate CSCs has recently become one of the most attractive therapeutic options, especially for abundant tumor-associated macrophages (TAMs). Herein, we developed a nebulized nanocatalytic medicine strategy in which iron-based nanoparticle-regulated TAMs effectively target CSC niches and trigger CSC ferroptosis in the early stage of lung cancer. Briefly, the iron-based nanoparticles can effectively accumulate in lung cancer microlesions (minimum 122 µm in diameter) through dextran-mediated TAM targeting by nebulization administration, and as a result, nanoparticle-internalized TAMs can play a predominant role of the iron factory in elevating the iron level surrounding CSC niches and destroying redox equilibrium through downregulating glucose-6-phosphate metabolite following their lysosomal degradation and iron metabolism. The altered microenvironment results in the enhanced sensitivity of CSCs to ferroptosis due to their high expression of the CD44 receptor mediating iron endocytosis. In an orthotopic mouse model of lung cancer, the initiation and progression of early lung cancer are significantly suppressed through ferroptosis-induced stemness reduction of CSCs by nebulization administration. This work presents a nebulized therapeutic strategy for early lung cancer through modulation of communications between TAMs and CSCs, which is expected to be a general approach for regulating primary microlesions and micrometastatic niches of lung cancer.

The Dynamic Interactions between Nanoparticles and Macrophages Impact Their Fate in Brain Tumors.

Functional nanomaterials such as iron oxide nanoparticles have been extensively explored for the diagnosis and treatment of central nervous system diseases. However, an insufficient understanding of the comprehensive nanomaterial-biological interactions in the brain hinders the nanomaterials from meeting the medical requirements for translational research. Here, FDA-approved ferumoxytol, an iron oxide nanoparticle, is chosen as the model nanomaterial for a systematic study of the dynamic interactions between ferumoxytol and immune cells, including microglia and macrophages, in the brain tumors. Strikingly, up to 90% of intratumorally injected ferumoxytol nanoparticles are recognized and phagocytized by tumor-associated microglia and macrophages. The dynamic trafficking progress of ferumoxytol in microglia and macrophages, including scavenger receptor-mediated endocytosis, lysosomal internalization, and extracellular vesicle-dominated excretion, is further studied. Importantly, the results demonstrate that extracellular vesicle-encapsulated nanoparticles could be gradually eliminated from the brain along with cerebrospinal fluid circulation over 21 days. Moreover, ferumoxytol exhibits no obvious long-term neurological toxicity after its injection. The study suggests that the dynamic biointeractions of nanoparticles with immune cells in the brain exert a key rate-limiting impact on the efficiency of targeting tumor cells and their in vivo fate and thus provide a deeper understanding of the nanomaterials in the brain for clinical applications.

Near Infrared Light Triggered Cucurbit[7]uril-Stabilized Gold Nanostars as a Supramolecular Nanoplatform for Combination Treatment of Cancer.

Developing a spatiotemporal-controlled platform with feasible synthesis and multifunctionality is highly desirable in the field of nanomedicine. Here, we present a near-infrared (NIR)-light-triggered approach to control the supramolecular assembly system for drug release and achieve synergistic chemo-photothermal therapy for cancer. A cucurbit[7]uril (CB[7]) stabilized gold nanostar (GNS) platform is designed to encapsulate the anticancer drug camptothecin (CPT) via host-guest chemistry. Importantly, CB[7] behaves not only as a surfactant to improve the stability of GNS in the aqueous solution but also as the cage for intermolecular assembly of CPT molecules. Moreover, without the competitive complexation, the drug release could be stimulated under NIR light irradiation. Synergistic treatment of cancer can be achieved by combining chemotherapy with the photothermal effect of GNS. This work develops a NIR-light-triggered cucurbituril-based drug-release approach that opens the door for remote control of drug release in the supramolecular assembly system.

Comparison of Two Approaches for the Attachment of a Drug to Gold Nanoparticles and Their Anticancer Activities.

Drug attachment is important in drug delivery for cancer chemotherapy. The elucidation of the release mechanism and biological behavior of a drug is essential for the design of delivery systems. Here, we used a hydrazone bond or an amide bond to attach an anticancer drug, doxorubicin (Dox), to gold nanoparticles (GNPs) and compared the effects of the chemical bond on the anticancer activities of the resulting Dox-GNPs. The drug release efficiency, cytotoxicity, subcellular distribution, and cell apoptosis of hydrazone-linked HDox-GNPs and amide-linked SDox-GNPs were evaluated in several cancer cells. HDox-GNPs exhibited greater potency for drug delivery via triggered release comediated by acidic pH and glutathione (GSH) than SDox-GNPs triggered by GSH alone. Dox released from HDox-GNPs was released in lysosomes and exerted its drug activity by entering the nuclei. Dox from SDox-GNPs was mainly localized in lysosomes, significantly reducing its efficacy against cancer cells. In addition, in vivo studies in tumor-bearing mice demonstrated that HDox-GNPs and SDox-GNPs both accumulate in tumor tissue. However, only HDox-GNPs enhanced inhibition of subcutaneous tumor growth. This study demonstrates that HDox-GNPs display significant advantages in drug release and antitumor efficacy.

Loading Nanoceria Improves Extracellular Vesicle Membrane Integrity and Therapy to Wounds in Aged Mice.

Wound healing is a programmed process through which tissue restores its integrity after an injury. Advancing age is a risk factor for delayed cutaneous wound healing; however, ideal therapeutic approaches for aged wound have not been developed yet. By dissecting the harsh microenvironment of aged wound, we propose an integrated chemical and biological strategy to mitigate two main hostile factors including oxidative stress and ischemia. Mesenchymal stem cell-derived extracellular vesicles (EVs) are a rising star in regenerative medicine due to their powerful facilitation in tissue repair and regeneration. However, the fragile lipid membrane limits their function under the oxidative stress microenvironment. Nanoceria is an antioxidative nanozyme; here, we reveal that nanoceria-loaded EVs derived from mesenchymal stem cells facilitate cutaneous wound healing in aged mice. DG-CeO2 was prepared via coating CeO2 covalently with d-glucose to promote their cellular endocytosis. DG-CeO2 was packaged into EVs under optimized hypoxic conditions (DG-CeO2 EVsHyp). We further demonstrated that DG-CeO2 EVsHyp had favorable biocompatibility and antioxidative and proangiogenic effects during the cutaneous wound healing in both young and aged mice. Further evidence revealed that DG-CeO2 EVsHyp-transferred miR-92a-3p/125b-5p and their targets associated with aging degeneration may be the potential mechanisms. Collectively, these findings highlight that nanoceria-loaded EVs released by engineered stem cells may represent a potential therapeutic approach for tissue regeneration in aged population.

Bioceramic Scaffolds with Antioxidative Functions for ROS Scavenging and Osteochondral Regeneration.

Osteoarthritis (OA) is a degenerative disease that involves excess reactive oxygen species (ROS) and osteochondral defects. Although multiple approaches have been developed for osteochondral regeneration, how to balance the biochemical and physical microenvironment in OA remains a big challenge. In this study, a bioceramic scaffold by 3D printed akermanite (AKT) integrated with hair-derived antioxidative nanoparticles (HNPs)/microparticles (HMPs) for ROS scavenging and osteochondral regeneration has been developed. The prepared bioscaffold with multi-mimetic enzyme effects, which can scavenge a broad spectrum of free radicals in OA, can protect chondrocytes under the ROS microenvironment. Importantly, the bioscaffold can distinctly stimulate the proliferation and maturation of chondrocytes due to the stimulation of the glucose transporter pathway (GLUT) via HNPs/HMPs. Furthermore, it significantly accelerated osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs). In vivo results showed that the bioscaffold can effectively enhance the osteochondral regeneration compared to the unmodified scaffold. The work shows that integration of antioxidant and mechanical properties via the bioscaffold is a promising strategy for osteochondral regeneration in OA treatment.

An Engineered Bacteria-Hybrid Microrobot with the Magnetothermal Bioswitch for Remotely Collective Perception and Imaging-Guided Cancer Treatment.

Microrobots driven by multiple propelling forces hold great potential for noninvasively targeted delivery in the physiologic environment. However, the remotely collective perception and precise propelling in a low Reynold's number bioenvironment remain the major challenges of microrobots to achieve desired therapeutic effects in vivo. Here, we reported a biohybrid microrobot that integrated with magnetic, thermal, and hypoxia sensitivities and an internal fluorescent protein as the dual reporter of thermal and positioning signals for targeted cancer treatment. There were three key elements in the microrobotic system, including the magnetic nanoparticle (MNP)-loaded probiotic Escherichia coli Nissle1917 (EcN@MNP) for spatially magnetic and hypoxia perception, a thermal-logic circuit engineered into the bacteria to control the biosynthesis of mCherry as the temperature and positioning reporter, and NDH-2 enzyme encoded in the EcN for enhanced anticancer therapy. According to the fluorescent-protein-based imaging feedback, the microrobot showed good thermal sensitivity and active targeting ability to the tumor area in a collective manner under the magnetic field. The cancer cell apoptosis was efficiently triggered in vitro and in vivo by the hybrid microrobot coupled with the effects of magnetothermal ablation and NDH-2-induced reactive oxygen species (ROS) damage. Our study demonstrates that the biohybrid EcN microrobot is an ideal platform to integrate the physical, biological, and chemical properties for collective perception and propelling in targeted cancer treatment.

Bioinspired Soft Microrobots with Precise Magneto-Collective Control for Microvascular Thrombolysis.

New-era soft microrobots for biomedical applications need to mimic the essential structures and collective functions of creatures from nature. Biocompatible interfaces, intelligent functionalities, and precise locomotion control in a collective manner are the key parameters to design soft microrobots for the complex bio-environment. In this work, a biomimetic magnetic microrobot (BMM) inspired by magnetotactic bacteria (MTB) with speedy motion response and accurate positioning is developed for targeted thrombolysis. Similar to the magnetosome structure in MTB, the BMM is composed of aligned iron oxide nanoparticle (MNP) chains embedded in a non-swelling microgel shell. Linear chains in BMMs are achieved due to the interparticle dipolar interactions of MNPs under a static magnetic field. Simulation results show that, the degree and speed of assembly is proportional to the field strength. The BMM achieves the maximum speed of 161.7 µm s-1 and accurate positioning control under a rotating magnetic field with less than 4% deviation. Importantly, the locomotion analyses of BMMs demonstrate the frequency-dependent synchronization under 8 Hz and asynchronization at higher frequencies due to the increased drag torque. The BMMs can deliver and release thrombolytic drugs via magneto-collective control, which is promising for ultra-minimal invasive thrombolysis.

Programmable ROS-Mediated Cancer Therapy via Magneto-Inductions.

Reactive oxygen species (ROS), a group of oxygen derived radicals and derivatives, can induce cancer cell death via elevated oxidative stress. A spatiotemporal approach with safe and deep-tissue penetration capabilities to elevate the intracellular ROS level is highly desirable for precise cancer treatment. Here, a mechanical-thermal induction therapy (MTIT) strategy is developed for a programmable increase of ROS levels in cancer cells via assembly of magnetic nanocubes integrated with alternating magnetic fields. The magneto-based mechanical and thermal stimuli can disrupt the lysosomes, which sequentially induce the dysfunction of mitochondria. Importantly, intracellular ROS concentrations are responsive to the magneto-triggers and play a key role for synergistic cancer treatment. In vivo experiments reveal the effectiveness of MTIT for efficient eradication of glioma and breast cancer. By remote control of the force and heat using magnetic nanocubes, MTIT is a promising physical approach to trigger the biochemical responses for precise cancer treatment.

Intercellular Crosstalk of Mesenchymal Stem Cells with Prostate Cancer Cells via Microvesicles Loaded with Magnetic Nanocubes for Targeted Magnetic Hyperthermia.

The targeted delivery of nanomedicines into solid tumors remains challenging in cancer treatment. Stem cells with tumortropic migration ability are promising as biocarriers to transport nanomedicines. The transportation of nanomedicines into cancer cells is the key step for tumor targeted delivery via stem cells. In this study, we designed a magnetic nanocube (scMNP) loaded in mesenchymal stem cells for magnetic hyperthermia of prostate cancer, and the delivery and transportation pathways into the cancer cells were fully investigated. The MSCs acted as the carrier of the loaded scMNPs along with the upregulation of CXCR4 for the migration to cancer cells. The therapeutic effect was mainly due to scMNPs via magnetic hyperthermia. Stem cell-derived microvesicles containing scMNPs played an essential role in the crosstalk between stem cells and cancer cells for targeted delivery. Both in vitro and in vivo studies demonstrated that the system showed satisfactory therapeutic efficiency under magnetic hyperthermia therapy. Our investigation presents a comprehensive study of magnetic nanoparticles in combination with MSCs and their extracellular microvesicles and is promising as an effective strategy for magnetic hyperthermia therapy of prostate cancer.

Therapeutic effect on experimental acute cerebral infarction is enhanced after nanoceria labeling of human umbilical cord mesenchymal stem cells.

BACKGROUND: Therapeutic applications of stem cells, especially mesenchymal stem cells, were once regarded as a promising therapy for mitigating acute cerebral infarction. Unfortunately, all the stem cell clinical trials have been futile. A new stroke therapeutic strategy of combining stem cells with nanotechnology has recently gained significant attention. The objective of this study was to evaluate the application of cerium oxide nanoparticle (nanoceria)-labeled human umbilical cord mesenchymal stem cells (HucMSCs) for stroke therapy. METHODS: In our study, cerium oxide nanoparticles were precovered with hyaluronic acid before labeling HucMSCs and the synergistic effects from both HucMSCs and cerium oxide nanoparticles were analyzed in in vivo and in vitro experiments. RESULTS: The nanoceria-labeled HucMSCs combined advantages from both sides, including the capacity for inflammatory modulation of HucMSCs and the antioxidant effects of nanoceria. Compared with either HucMSCs or nanoceria individually, nanoceria-labeled HucMSCs exerted significantly enhanced capacities after gaining combined antioxidant and anti-inflammatory effects. CONCLUSION: Our findings suggest a novel strategy with effective and well-tolerated applications of stem cells for acute cerebral infarction therapy after modification of cells with nanomaterials.

Intelligent Photosensitive Mesenchymal Stem Cells and Cell-Derived Microvesicles for Photothermal Therapy of Prostate Cancer.

Targeted delivery of nanomedicines into the tumor site and improving the intratumoral distribution remain challenging in cancer treatment. Here, we report an effective transportation system utilizing both of mesenchymal stem cells (MSCs) and their secreted microvesicles containing assembled gold nanostars (GNS) for targeted photothermal therapy of prostate cancer. The stem cells act as a cell carrier to actively load and assemble GNS into the lysosomes. Accumulation of GNS in the lysosomes facilitates the close interaction of nanoparticles, which could result in a 20 nm red-shift of surface plasmon resonance of GNS with a broad absorption in the near infrared region. Moreover, the MSCs can behave like an engineering factory to pack and release the GNS clusters into microvesicles. The secretion of GNS can be stimulated via light irradiation, providing an external trigger-assisted approach to encapsulate nanoparticles into cell derived microvesicles. In vivo studies demonstrate that GNS-loaded MSCs have an extensive intratumoral distribution, as monitored via photoacoustic imaging, and efficient antitumor effect under light exposure in a prostate-cancer subcutaneous model by intratumoral and intravenous injection. Our work presents a light-responsive transportation approach for GNS in combination of MSCs and their extracellular microvesicles and holds the promise as an effective strategy for targeted cancer therapy including prostate cancer.

A feasible strategy for self-assembly of gold nanoparticles via dithiol-PEG for photothermal therapy of cancers.

We designed and explored self-assembled gold nanoparticles (SAGNPs) by introducing dithiol modified polyethylene glycol (PEG) for internanoparticle cross-linking. SAGNPs could enhance uptake into cancer cells and be disintegrated by glutathione (GSH) to achieve tumor microenvironment-activated biodegradation. This assembled structure improved the photothermal effect compared to single gold nanospheres.

A Light-Triggered Mesenchymal Stem Cell Delivery System for Photoacoustic Imaging and Chemo-Photothermal Therapy of Triple Negative Breast Cancer.

Targeted therapy is highly challenging and urgently needed for patients diagnosed with triple negative breast cancer (TNBC). Here, a synergistic treatment platform with plasmonic-magnetic hybrid nanoparticle (lipids, doxorubicin (DOX), gold nanorods, iron oxide nanocluster (LDGI))-loaded mesenchymal stem cells (MSCs) for photoacoustic imaging, targeted photothermal therapy, and chemotherapy for TNBC is developed. LDGI can be efficiently taken up into the stem cells with good biocompatibility to maintain the cellular functions. In addition, CXCR4 on the MSCs is upregulated by iron oxide nanoparticles in the LDGI. Importantly, the drug release and photothermal therapy can be simultaneously achieved upon light irradiation. The released drug can enter the cell nucleus and promote cell apoptosis. Interestingly, light irradiation can control the secretion of cellular microvehicles carrying LDGI for targeted treatment. A remarkable in vitro anticancer effect is observed in MDA-MB-231 with near-infrared laser irradiation. In vivo studies show that the MSCs-LDGI has the enhanced migration and penetration abilities in the tumor area via both intratumoral and intravenous injection approaches compared with LDGI. Subsequently, MSCs-LDGI shows the best antitumor efficacy via chemo-photothermal therapy compared to other treatment groups in the TNBC model of nude mice. Thus, MSCs-LDGI multifunctional system represents greatly synergistic potential for cancer treatment.

Self-Assembly of Gold Nanoparticles Shows Microenvironment-Mediated Dynamic Switching and Enhanced Brain Tumor Targeting.

Inorganic nanoparticles with unique physical properties have been explored as nanomedicines for brain tumor treatment. However, the clinical applications of the inorganic formulations are often hindered by the biological barriers and failure to be bioeliminated. The size of the nanoparticle is an essential design parameter which plays a significant role to affect the tumor targeting and biodistribution. Here, we report a feasible approach for the assembly of gold nanoparticles into ~80 nm nanospheres as a drug delivery platform for enhanced retention in brain tumors with the ability to be dynamically switched into the single formulation for excretion. These nanoassemblies can target epidermal growth factor receptors on cancer cells and are responsive to tumor microenvironmental characteristics, including high vascular permeability and acidic and redox conditions. Anticancer drug release was controlled by a pH-responsive mechanism. Intracellular L-glutathione (GSH) triggered the complete breakdown of nanoassemblies to single gold nanoparticles. Furthermore, in vivo studies have shown that nanospheres display enhanced tumor-targeting efficiency and therapeutic effects relative to single-nanoparticle formulations. Hence, gold nanoassemblies present an effective targeting strategy for brain tumor treatment.

Tetrandrine suppresses articular inflammatory response by inhibiting pro-inflammatory factors via NF-κB inactivation.

Targeting activated macrophages using anti-inflammatory phytopharmaceuticals has been proposed as general therapeutic approaches for rheumatic diseases. Besides macrophages, chondrocytes are another promising target of anti-inflammatory agents. Tetrandrine is a major bisbenzylisoquinoline alkaloid isolated from Stephania tetrandrae S. Moore which has been used for 2,000 years as an antirheumatic herbal drug in China. Although, the anti-inflammatory effect of tetrandrine has been demonstrated, the mechanism has not been clearly clarified. In this study, we designed a comprehensive anti-inflammatory evaluation system for tetrandrine, including complete Freund's adjuvant (CFA)-induced arthritis rat, LPS-induced macrophage RAW 264.7 cells, and chondrogenic ATDC5 cells. The results showed that tetrandrine alleviated CFA-induced foot swelling, synovial inflammation, and pro-inflammatory cytokines secretion. Tetrandrine could inhibit IL-6, IL-1ß, and TNF-α expression via blocking the nuclear translocation of nuclear factor (NF)-κB p65 in LPS-induced RAW 264.7 cells. Moreover, ATDC5 cells well responded to LPS induced pro-inflammatory mediators secretion and tissue degradation, and tetrandrine could also inhibit the production of nitric oxide and prostaglandin E2 , as well as the expression of matrix metalloproteinase (MMP)-3 and tissue inhibitor of metalloproteinase (TIMP)-1 via inhibiting IκBα phosphorylation and degradation. In conclusion, the results showed that one of the anti-inflammatory mechanisms of tetrandrine was inhibiting IκBα and NF-κB p65 phosphorylation in LPS-induced macrophage RAW 264.7 cells and chondrogenic ATDC5 cells. Moreover, we introduce a vigorous in vitro cell screening system, LPS-induced murine macrophage RAW 264.7 cells coupling chondrogenic ADTC5 cells, for screening anti-rheumatic drugs. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:1557-1568, 2016.