Highly bioactive zeolitic imidazolate framework-8-capped nanotherapeutics for efficient reversal of reperfusion-induced injury in ischemic stroke

Engineering two-dimensional silicene composite nanosheets for dual-sensitized and photonic hyperthermia-augmented cancer radiotherapy

The rapid development of nanotechnology has triggered the emerging of tremendous theranostic nanoplatforms for combating cancers. Silicene, as an emerging two-dimensional (2D) material, has been recently explored as therapeutic agent due to their desirable biodegradation and strong photothermal-conversion performance. However, the rational design of silicene-based composites for further exerting multifunctional medical applications is still highly challenging. Herein, we report on the construction of silicene-based silicene@Pt composite nanosheets for computed tomography (CT)/photoacoustic (PA) imaging-guided dual-sensitized radiotherapy combined with photonic tumor hyperthermia, which has been achieved by a seed-growth approach to in situ grow Pt components onto silicene nanosheets' surface. Especially, by functionalization of Pt components, these nanosheets could act as both contrast agents for CT imaging and dual radio-sensitizing agents for radiotherapy, which could deposit Pt-involved radiation energy (sensitized therapeutic process I) and overcome hypoxia-associated radio-resistance by Pt-catalytic O₂ generation from overexpressed H₂O₂ within the tumor microenvironment (sensitized therapeutic process II). The strong photothermal-conversion performance of silicene nanosheets not only endowed silicene@Pt composite nanosheets with photoacoustic imaging property, but also realized the photonic tumor hyperthermia and achieved a combined therapeutic effect with radiotherapy. This work not only broadens the biomedical applications of silicene, but also develops functionalization strategies of silicene for versatile biomedical applications.

Engineering EHD1-Targeted Natural Borneol Nanoemulsion Potentiates Therapeutic Efficacy of Gefitinib against Nonsmall Lung Cancer

Despite the effective targeting of the epidermal growth factor receptor (EGFR), the use of gefitinib (GFT) for nonsmall cell lung cancer (NSCLC) treatment meets a failure because of the insufficient drug accumulation in the tumor region. Therefore, developing chemosensitizers of GFT with synergistic therapeutic effects is urgently needed for advanced cancer therapy. Herein, a natural chemosensitizer, natural borneol (NB), is reformulated as an oil-in-water nanoemulsion to enhance its solubility, distribution, and to ultimately increase the therapeutic index with GFT. The nanolization of NB (NBNPs) displays stronger targeted delivery and cytotoxicity than NB by selectively identifying eight specific protein targets in A549 NSCLC cells as revealed by the proteomic studies. Consistently, NBNPs realize stronger chemosensitization effects than NB with GFT by effectively regulating EGFR/EHD1-mediated apoptosis in A549 NSCLC cells. Owing to the satisfying synergistic effect between NBNPs and GFT, the combined therapy not only enhances the anticancer ability of GFT against NSCLC proliferation but also avoids heavy double toxicity in vivo. This finding demonstrates the effective synergism between NBNPs and GFT with clear mechanistic investigation and is expected to extend the application of NBNPs as a novel chemosensitizer for advanced cancer chemotherapy.

Rapid visualizing and pathological grading of bladder tumor tissues by simple nanodiagnostics

Developing a tissue diagnosis technology to avoid the complicated processes and the usage of expensive reagents while achieving rapid pathological grading diagnosis to provide a better strategy for clinical treatment is an important strategy of tumor diagnose. Herein, we selected the integrin αvβ3 as target based on the analysis of clinical data, and then designed a stable and cancer-targeted selenium nanosystem (RGD@SeNPs) by using RGD polypeptide as the targeting modifier. In vitro experiments showed that RGD@SeNPs could specifically recognized tumor cells, especially in co-culture cells model. The RGD@SeNPs can be used for clinical samples staining without the use of primary and secondary antibody. Fluorescence difference of the tissue specimens staining with RGD@SeNPs could be used to distinguish normal tissues and tumor tissues or estimate different pathological grades of cancer at tissue level. 132 clinical tumor specimens with three types of tumor and 76 non-tumor specimens were examined which verified that the nanoparticles could specific and sensitive distinguish tumor tissue from normal tissue with a specificity of 92% and sensitivity of 96%. These results demonstrate the potential of cancer-targeted RGD@SeNPs as translational nanodiagnostics for rapid visualizing and pathological grading of bladder tumor tissues in clinical specimens.

Biomedical Application of Reactive Oxygen Species-Responsive Nanocarriers in Cancer, Inflammation, and Neurodegenerative Diseases

Numerous pathological conditions, including cancer, inflammatory diseases, and neurodegenerative diseases, are accompanied by overproduction of reactive oxygen species (ROS). This makes ROS vital flagging molecules in disease pathology. ROS-responsive drug delivery platforms have been developed. Nanotechnology has been broadly applied in the field of biomedicine leading to the progress of ROS-responsive nanoparticles. In this review, we focused on the production and physiological/pathophysiological impact of ROS. Particular emphasis is put on the mechanisms and effects of abnormal ROS levels on oxidative stress diseases, including cancer, inflammatory disease, and neurodegenerative diseases. Finally, we summarized the potential biomedical applications of ROS-responsive nanocarriers in these oxidative stress diseases. We provide insights that will help in the designing of new ROS-responsive nanocarriers for various applications.

Smart Microenvironment-Responsive Organocopper(II) Supramolecular Polymers to Regulate the Stability and Anticancer Efficacy by Different Substituents

The search for chemotherapeutic drugs with a high efficiency and low toxicity continues to be a challenge in tumor treatment for scientists. Organometallic supramolecular polymers are an attractive option to achieve this goal, not only due to the fact that they possess both advantages of metal complexes and nanostructures but also because they are usually sensitive to pH. Here, we report the design and synthesis of a series novel smart microenvironment-responsive organocopper(II) supramolecular polymers with various substituted ligands to regulate their stability and anticancer efficacy. The investigation of the possible mechanisms revealed that the organocopper(II) polymers enter cancer cells through endocytosis and then induce apoptosis of cancer cells. Furthermore, the in vivo anticancer efficacy study demonstrated that these organocopper(II) polymers inhibited the tumor growth effectively without damage to the major organs. Overall, the organocopper(II) supramolecular polymers present a promising pathway to achieve high-efficiency and low-toxicity chemotherapy.

Adjusting the lipid-water distribution coefficient of iridium(III) complexes to enhance the cellular penetration and treatment efficacy to antagonize cisplatin resistance in cervical cancer

The effective design of metal complexes to manipulate their lipid-water distribution coefficient is an appealing strategy for improving their cellular penetration and treatment efficacy. Here, we conveniently synthesized three iridium (Ir) complexes with red fluorescence via the simple non-conjugate modification of the side arm of the ligand. Bio-evaluation revealed that upon adding non-conjugate selenium (Se) arene derivatives, the lipid-water distribution coefficient of Ir-Se was found to be suitable, not only decreasing the toxic side effects of complexes to normal cells, but also effectively improving their anticancer activity via enhancing their penetration into tumor cells. Moreover, mechanistic investigations demonstrated that Ir-Se entered R-HeLa cells through endocytosis, and triggered apoptosis via the down-regulation of the mitochondrial membrane potential and excessive production of singlet oxygen, thereby possessing a highly effective cytotoxicity to antagonize cisplatin resistance. Therefore, we developed a convenient strategy to derive functional metal complexes and revealed that the introduction of Se on the side arm of the ligand provided the complexes with the capacity to reverse multidrug resistance.

Uniting Drug and Delivery: Metal Oxide Hybrid Nanotherapeutics for Skin Wound Care

Wound care and soft tissue repair have been a major human concern for millennia. Despite considerable advancements in standards of living and medical abilities, difficult-to-heal wounds remain a major burden for patients, clinicians and the healthcare system alike. Due to an aging population, the rise in chronic diseases such as vascular disease and diabetes, and the increased incidence of antibiotic resistance, the problem is set to worsen. The global wound care market is constantly evolving and expanding, and has yielded a plethora of potential solutions to treat poorly healing wounds. In ancient times, before such a market existed, metals and their ions were frequently used in wound care. In combination with plant extracts, they were used to accelerate the healing of burns, cuts and combat wounds. With the rise of organic chemistry and small molecule drugs and ointments, researchers lost their interest in inorganic materials. Only recently, the advent of nano-engineering has given us a toolbox to develop inorganic materials on a length-scale that is relevant to wound healing processes. The robustness of synthesis, as well as the stability and versatility of inorganic nanotherapeutics gives them potential advantages over small molecule drugs. Both bottom-up and top-down approaches have yielded functional inorganic nanomaterials, some of which unite the wound healing properties of two or more materials. Furthermore, these nanomaterials do not only serve as the active agent, but also as the delivery vehicle, and sometimes as a scaffold. This review article provides an overview of inorganic hybrid nanotherapeutics with promising properties for the wound care field. These therapeutics include combinations of different metals, metal oxides and metal ions. Their production, mechanism of action and applicability will be discussed in comparison to conventional wound healing products.

TRPM8-regulated calcium mobilization plays a critical role in synergistic chemosensitization of Borneol on Doxorubicin

Background: Lung cancer has a high mortality rate and is resistant to multiple chemotherapeutics. Natural Borneol (NB) is a monoterpenoid compound that facilitates the bioavailability of drugs. In this study, we investigated the effects of NB on chemosensitivity in the A549 human lung adenocarcinoma cell line and to elucidate therapeutic molecular target of NB. Methods: The chemosensitivity effects of NB in A549 cells were examined by MTT assay. The mechanism of NB action was evaluated using flow cytometry and Western blotting assays. Surface plasmon resonance (SPR) and LC-MS combined analysis (MS-SPRi) was performed to elucidate the candidate molecular target of NB. The chemosensitizing capacity of NB in vivo was assessed in nude mice bearing A549 tumors. Results: NB pretreatment sensitized A549 cells to low doxorubicin (DOX) dosage, leading to a 15.7% to 41.5% increase in apoptosis. This increase was correlated with ERK and AKT inactivation and activation of phospho-p38 MAPK, phospho-JNK, and phosphor-p53. Furthermore, this synergism depends on reactive oxygen species (ROS) generation. MS-SPRi analysis revealed that transient receptor potential melastatin-8 (TRPM8) is the candidate target of NB in potentiating DOX killing potency. Genetically, TRPM8 knock-down significantly suppresses the chemosensitizing effects of NB and inhibits ROS generation through restraining calcium mobilization. Moreover, pretreatment with NB synergistically enhances the anticancer effects of DOX to delay tumor progression in vivo. Conclusions: These results suggest that TRPM8 may be a valid therapeutic target in the potential application of NB, and show that NB is a chemosensitizer for lung cancer treatment.

Role of the neurovascular unit in the process of cerebral ischemic injury

Cerebral ischemic injury exhibits both high morbidity and mortality worldwide. Traditional research of the pathogenesis of cerebral ischemic injury has focused on separate analyses of the involved cell types. In recent years, the neurovascular unit (NVU) mechanism of cerebral ischemic injury has been proposed in modern medicine. Hence, more effective strategies for the treatment of cerebral ischemic injury may be provided through comprehensive analysis of brain cells and the extracellular matrix. However, recent studies that have investigated the function of the NVU in cerebral ischemic injury have been insufficient. In addition, the metabolism and energy conversion of the NVU depend on interactions among multiple cell types, which make it difficult to identify the unique contribution of each cell type. Therefore, in the present review, we comprehensively summarize the regulatory effects and recovery mechanisms of four major cell types (i.e., astrocytes, microglia, brain-microvascular endothelial cells, and neurons) in the NVU under cerebral ischemic injury, as well as discuss the interactions among these cell types in the NVU. Furthermore, we discuss the common signaling pathways and signaling factors that mediate cerebral ischemic injury in the NVU, which may help to provide a theoretical basis for the comprehensive elucidation of cerebral ischemic injury.

Lentinan-functionalized selenium nanosystems with high permeability infiltrate solid tumors by enhancing transcellular transport

The delivery of nanomedicines into internal areas of solid tumors is a great challenge for the design of chemotherapeutic drugs and the realization of their successful application. Herein, we synthesized stable and efficient selenium nanoparticles (SeNPs) with an ideal size and a transcellular transport capability for the penetration and treatment of a solid tumor, utilizing Tw-80 as a dispersing agent and mushroom polysaccharide lentinan (LET) as a decorator. In vitro cellular experiments demonstrated that this nanosystem, LET-Tw-SeNPs, renders significant cellular uptake of HepG2 by receptor-mediated endocytosis and exhibits predominant transcellular transport and penetration capacity towards HepG2 tumor spheroids. Moreover, this therapeutic agent simultaneously inhibits the proliferation and migration of HepG2 cells via a cell cycle arrest pathway. Internalized LET-Tw-SeNPs give rise to the overproduction of intracellular reactive oxygen species (ROS), thus inducing mitochondrial rupture. Meanwhile, pharmacokinetic analysis showed that LET-Tw-SeNPs displayed a long half-life in blood. Altogether, this study demonstrates an inventive strategy for designing nanosystems with high permeability and low blood clearance, in order to achieve efficient in-depth tumor drug delivery and future clinical treatment of solid tumors.

Designing Dihydrofolate Reductase Inhibitors as X-ray Radiosensitizers to Reverse Radioresistance of Cervical Cancer

X-ray radiotherapy has been widely used in the treatment of cervical cancer, a common gynecologic malignant tumor. However, the therapeutic efficacy tends to be indistinctive. One major reason for this is amplification of the dihydrofolate reductase (DHFR) gene, which causes an increase in DHFR activity and attenuation of the treatment effect. To solve this problem, we synthesized a series of DHFR inhibitors derived from methotrexate (MTX) analogues as radiotherapy sensitizers. Activity screening revealed that compound 2a exerted the best inhibitory effect toward DHFR activity. In combination with X-ray radiotherapy (4 Gy), 2a showed much more prominent antiproliferative activity on cervical cancer cells than 2a or X-rays alone and revealed higher selectivity and radiosensitization than MTX. In vitro experiments showed that 2a + X-rays significantly induced cell apoptosis, as revealed by the increase in the Sub-G1 population and activation of caspase 3, 8, and 9. The in vivo antitumor effect demonstrated that in the presence of X-rays, 2a effectively suppressed tumor growth and did not cause obvious side effects. In conclusion, as a DHFR inhibitor, 2a successfully reversed the radioresistance problem induced by radiotherapy and greatly promoted the therapeutic effect. This is a promising candidate for tumor treatment that deserves further research and development. This study clearly demonstrates that DHFR inhibitors could be developed as promising radiosensitizers in the treatment of cervical cancer and that further research to improve their activity and potential in future clinical use is deserved.

Designing immunogenic nanotherapeutics for photothermal-triggered immunotherapy involving reprogramming immunosuppression and activating systemic antitumor responses

Low tumor mutational burden and absence of T cells within the tumor sites are typical characteristics of "cold immune tumors" that paralyzes the immune system. The strategy of reversing "cold tumors" to "hot tumors" infiltrated high degree of T cells in order to activate anti-tumor immunity has attracted lots of attentions. Herein, immunogenic core-shell Au@Se NPs is fabricated by gold-selenium coordination bond to realize nanoparticles-mediated local photothermal-triggered immunotherapy. As expected, incorporation of gold nanostars (AuNSs) with improved photothermal stability and conversion efficiency promotes the disintegration and transformation of selenium nanoparticles (SeNPs), thus leading to enhanced cancer cells apoptosis by producing higher hyperthermia. Moreover, the results of in vivo experiments demonstrate that the synergy between SeNPs-mediated chemotherapy and AuNSs-induced photothermal therapy not only generated a localized antitumor-immune response with excellent cancer killing effect under the presence of tumor-associated antigens, but also effectively reprogrammed the tumor associated macrophages (TAMs) from M2 to M1 phenotype with tumoricidal activity to devour distant tumors. Without a doubt, this study not only provides a potent strategy to reverse the immunosuppressive tumor microenvironment, but also offers a new insight for potential clinical application in tumor immunotherapy.

Nanotherapeutic modulation of excitotoxicity and oxidative stress in acute brain injury

Excitotoxicity is a primary pathological process that occurs during stroke, traumatic brain injury (TBI), and global brain ischemia such as perinatal asphyxia. Excitotoxicity is triggered by an overabundance of excitatory neurotransmitters within the synapse, causing a detrimental cascade of excessive sodium and calcium influx, generation of reactive oxygen species, mitochondrial damage, and ultimately cell death. There are multiple potential points of intervention to combat excitotoxicity and downstream oxidative stress, yet there are currently no therapeutics clinically approved for this specific purpose. For a therapeutic to be effective against excitotoxicity, the therapeutic must accumulate at the disease site at the appropriate concentration at the right time. Nanotechnology can provide benefits for therapeutic delivery, including overcoming physiological obstacles such as the blood-brain barrier, protect cargo from degradation, and provide controlled release of a drug. This review evaluates the use of nano-based therapeutics to combat excitotoxicity in stroke, TBI, and hypoxia-ischemia with an emphasis on mitigating oxidative stress, and consideration of the path forward toward clinical translation.

Metal–organic frameworks: a future toolbox for biomedicine?

The present review focuses on the use of Metal–Organic Frameworks, (MOFs) highlighting the most recent developments in the biological field and as bio-sensors.