Mechanism of anti-angiogenic property of gold nanoparticles: role of nanoparticle size and surface charge

Metal-based nanoparticle in cancer treatment: lessons learned and challenges

Cancer, being one of the deadliest diseases, poses significant challenges despite the existence of traditional treatment approaches. This has led to a growing demand for innovative pharmaceutical agents that specifically target cancer cells for effective treatment. In recent years, the use of metal nanoparticles (NPs) as a promising alternative to conventional therapies has gained prominence in cancer research. Metal NPs exhibit unique properties that hold tremendous potential for various applications in cancer treatment. Studies have demonstrated that certain metals possess inherent or acquired anticancer capabilities through their surfaces. These properties make metal NPs an attractive focus for therapeutic development. In this review, we will investigate the applicability of several distinct classes of metal NPs for tumor targeting in cancer treatment. These classes may include gold, silver, iron oxide, and other metals with unique properties that can be exploited for therapeutic purposes. Additionally, we will provide a comprehensive summary of the risk factors associated with the therapeutic application of metal NPs. Understanding and addressing these factors will be crucial for successful clinical translation and to mitigate any potential challenges or failures in the translation of metal NP-based therapies. By exploring the therapeutic potential of metal NPs and identifying the associated risk factors, this review aims to contribute to the advancement of cancer treatment strategies. The anticipated outcome of this review is to provide valuable insights and pave the way for the advancement of effective and targeted therapies utilizing metal NPs specifically for cancer patients.

Characterization of Gold-Enhanced Titania: Boosting Cell Proliferation and Combating Bacterial Infestation

BACKGROUND

In this study an approach was made to efficaciously synthesize gold enhanced titania nanorods by electrospinning. This study aims to address effects of gold enhanced titania nanorods on muscle precursor cells. Additionally, implant related microbial infections are prime cause of various disastrous diseases. So, there is predictable demand for synthesis of novel materials with multifunctional adaptability.

METHODS

Herein, gold nanoparticles were attached on titania nanorods and described using many sophisticated procedures such as XRD, SEM, EDX and TEM. Antimicrobial studies were probed against Gram-negative Escherichia coli. C2C12 cell lines were exposed to various doses of as-prepared gold enhanced titania nanorods in order to test in vitro cytotoxicity and proliferation. Cell sustainability was assessed through Cell Counting Kit-8 assay at regular intervals. A phase-contrast microscope was used to examine morphology of exposed C2C12 cells and confocal laser scanning microscope was used to quantify cell viability.

RESULTS

The findings indicate that titania nanorods enhanced with gold exhibit superior antimicrobial efficacy compared to pure titania. Furthermore, newly synthesized gold-enhanced titania nanorods illustrate that cell viability follows a time and concentration dependent pattern.

CONCLUSION

Consequently, our study provides optimistic findings indicating that titania nanorods adorned with gold hold significant potential as foundational resource for developing forthcoming antimicrobial materials, suitable for applications both in medical and biomedical fields. This work also demonstrates that in addition to being extremely biocompatible, titania nanorods with gold embellishments may be used in a range of tissue engineering applications in very near future.

Recent advances in hepatocellular carcinoma-targeted nanoparticles

In the field of medicine, we often brave the unknown like interstellar explorers, especially when confronting the formidable opponent of hepatocellular carcinoma (HCC). The global burden of HCC remains significant, with suboptimal treatment outcomes necessitating the urgent development of novel drugs and treatments. While various treatments for liver cancer, such as immunotherapy and targeted therapy, have emerged in recent years, improving their transport and therapeutic efficiency, controlling their targeting and release, and mitigating their adverse effects remains challenging. However, just as we grope through the darkness, a glimmer of light emerges-nanotechnology. Recently, nanotechnology has attracted attention because it can increase the local drug concentration in tumors, reduce systemic toxicity, and has the potential to enhance the effectiveness of precision therapy for HCC. However, there are also some challenges hindering the clinical translation of drug-loaded nanoparticles (NPs). Just as interstellar explorers must overcome interstellar dust, we too must overcome various obstacles. In future researches, the design and development of nanodelivery systems for novel drugs treating HCC should be the first attention. Moreover, researchers should focus on the active targeting design of various NPs. The combination of the interventional therapies and drug-loaded NPs will greatly advance the process of precision HCC therapy.

Emerging applications of anti-angiogenic nanomaterials in oncotherapy

Angiogenesis is the process of generating new blood vessels from pre-existing vasculature. Under normal conditions, this process is delicately controlled by pro-angiogenic and anti-angiogenic factors. Tumor cells can produce plentiful pro-angiogenic molecules promoting pathological angiogenesis for uncontrollable growth. Therefore, anti-angiogenic therapy, which aims to inhibit tumor angiogenesis, has become an attractive approach for oncotherapy. However, classic anti-angiogenic agents have several limitations in clinical use, such as lack of specific targeting, low bioavailability, and poor therapeutic outcomes. Hence, alternative angiogenic inhibitors are highly desired. With the emergence of nanotechnology, various nanomaterials have been designed for anti-angiogenesis purposes, offering promising features like excellent targeting capabilities, reduced side effects, and enhanced therapeutic efficacy. In this review, we describe tumor vascular features, discuss current dilemma of traditional anti-angiogenic medicines in oncotherapy, and underline the potential of nanomaterials in tumor anti-angiogenic therapy. Moreover, we discuss the current challenges of anti-angiogenic cancer treatment. We expect that this summary of anti-angiogenic nanomaterials in oncotherapy will offer valuable insights, facilitating their extensive applications in the future.

Biodegradable piezoelectric skin-wound scaffold

Electrical stimulation (ES) induces wound healing and skin regeneration. Combining ES with the tissue-engineering approach, which relies on biomaterials to construct a replacement tissue graft, could offer a self-stimulated scaffold to heal skin-wounds without using potentially toxic growth factors and exogenous cells. Unfortunately, current ES technologies are either ineffective (external stimulations) or unsafe (implanted electrical devices using toxic batteries). Hence, we propose a novel wound-healing strategy that integrates ES with tissue engineering techniques by utilizing a biodegradable self-charged piezoelectric PLLA (Poly (l-lactic acid)) nanofiber matrix. This unique, safe, and stable piezoelectric scaffold can be activated by an external ultrasound (US) to produce well-controlled surface-charges with different polarities, thus serving multiple functions to suppress bacterial growth (negative surface charge) and promote skin regeneration (positive surface charge) at the same time. We demonstrate that the scaffold activated by low intensity/low frequency US can facilitate the proliferation of fibroblast/epithelial cells, enhance expression of genes (collagen I, III, and fibronectin) typical for the wound healing process, and suppress the growth of S. aureus and P. aeruginosa bacteria in vitro simultaneously. This approach induces rapid skin regeneration in a critical-sized skin wound mouse model in vivo. The piezoelectric PLLA skin scaffold thus assumes the role of a multi-tasking, biodegradable, battery-free electrical stimulator which is important for skin-wound healing and bacterial infection prevention simultaneuosly.

Transition metals in angiogenesis - A narrative review

The aim of this paper is to offer a narrative review of the literature regarding the influence of transition metals on angiogenesis, excluding lanthanides and actinides. To our knowledge there are not any reviews up to date offering such a summary, which inclined us to write this paper. Angiogenesis describes the process of blood vessel formation, which is an essential requirement for human growth and development. When the complex interplay between pro- and antiangiogenic mediators falls out of balance, angiogenesis can quickly become harmful. As it is so fundamental, both its inhibition and enhancement take part in various diseases, making it a target for therapeutic treatments. Current methods come with limitations, therefore, novel agents are constantly being researched, with metal agents offering promising results. Various transition metals have already been investigated in-depth, with studies indicating both pro- and antiangiogenic properties, respectively. The transition metals are being applied in various formulations, such as nanoparticles, complexes, or scaffold materials. Albeit the increasing attention this field is receiving, there remain many unanswered questions, mostly regarding the molecular mechanisms behind the observed effects. Notably, approximately half of all the transition metals have not yet been investigated regarding potential angiogenic effects. Considering the promising results which have already been established, it should be of great interest to begin investigating the remaining elements whilst also further analyzing the established effects.

Molecularly Imprinted Nanomedicine for Anti-angiogenic Cancer Therapy via Blocking Vascular Endothelial Growth Factor Signaling

The VEGF-VEGFR2 (VEGF = vascular endothelial growth factor) signaling has been a promising target in cancer therapy. However, because conventional anti-angiogenic therapeutics suffer from drawbacks, particularly severe side effects, novel anti-angiogenic strategies are much needed. Herein, we report the rational engineering of VEGF-targeted molecularly imprinted polymer nanoparticles (nanoMIP) for anti-angiogenic cancer therapy. The anti-VEGF nanomedicine was prepared via a state-of-the-art molecular imprinting approach using the N-terminal epitope of VEGF as the template. The nanoMIP could target the two major pro-angiogenic isoforms (VEGF165 and VEGF121) with high affinity and thereby effectively block the VEGF-VEGFR2 signaling, yielding a potent anti-angiogenic effect of "killing two birds with one stone". In vivo experiments demonstrated that the anti-VEGF nanoMIP effectively suppressed tumor growth via anti-angiogenesis in a xenograft model of human colon carcinoma without apparent side effects. Thus, this study not only proposes an unprecedented anti-angiogenic strategy for cancer therapy but also provides a new paradigm for the rational development of MIPs-based "drug-free" nanomedicines.

Progress on the pathological tissue microenvironment barrier-modulated nanomedicine

Imbalance in the tissue microenvironment is the main obstacle to drug delivery and distribution in the human body. Before penetrating the pathological tissue microenvironment to the target site, therapeutic agents are usually accompanied by three consumption steps: the first step is tissue physical barriers for prevention of their penetration, the second step is inactivation of them by biological molecules, and the third step is a cytoprotective mechanism for preventing them from functioning on specific subcellular organelles. However, recent studies in drug-hindering mainly focus on normal physiological rather than pathological microenvironment, and the repair of damaged physiological barriers is also rarely discussed. Actually, both the modulation of pathological barriers and the repair of damaged physiological barriers are essential in the disease treatment and the homeostasis maintenance. In this review, we present an overview describing the latest advances in the generality of these pathological barriers and barrier-modulated nanomedicine. Overall, this review holds considerable significance for guiding the design of nanomedicine to increase drug efficacy in the future.

Recent advances of smart materials for ocular drug delivery

Owing to the variety and complexity of ocular diseases and the natural ocular barriers, drug therapy for ocular diseases has significant limitations, such as poor drug targeting to the site of the disease, poor drug penetration, and short drug retention time in the vitreous body. With the development of biotechnology, biomedical materials have reached the "smart" stage. To date, despite their inability to overcome all the aforementioned drawbacks, a variety of smart materials have been widely tested to treat various ocular diseases. This review analyses the most recent developments in multiple smart materials (inorganic particles, polymeric particles, lipid-based particles, hydrogels, and devices) to treat common ocular diseases and discusses the future directions and perspectives regarding clinical translation issues. This review can help researchers rationally design more smart materials for specific ocular applications.

pH-Responsive, Charge-Reversing Layer-by-Layer Nanoparticle Surfaces Enhance Biofilm Penetration and Eradication

Microbes entrenched within biofilms can withstand 1000-fold higher concentrations of antibiotics, in part due to the viscous extracellular matrix that sequesters and attenuates antimicrobial activity. Nanoparticle (NP)-based therapeutics can aid in delivering higher local concentrations throughout biofilms as compared to free drugs alone, thereby enhancing the efficacy. Canonical design criteria dictate that positively charged nanoparticles can multivalently bind to anionic biofilm components and increase biofilm penetration. However, cationic particles are toxic and are rapidly cleared from circulation in vivo, limiting their use. Therefore, we sought to design pH-responsive NPs that change their surface charge from negative to positive in response to the reduced biofilm pH microenvironment. We synthesized a family of pH-dependent, hydrolyzable polymers and employed the layer-by-layer (LbL) electrostatic assembly method to fabricate biocompatible NPs with these polymers as the outermost surface. The NP charge conversion rate, dictated by polymer hydrophilicity and the side-chain structure, ranged from hours to undetectable within the experimental timeframe. LbL NPs with an increasingly fast charge conversion rate more effectively penetrated through, and accumulated throughout, wildtype (PAO1) and mutant overexpressing biomass (ΔwspF) Pseudomonas aeruginosa biofilms. Finally, tobramycin, an antibiotic known to be trapped by anionic biofilm components, was loaded into the final layer of the LbL NP. There was a 3.2-fold reduction in ΔwspF colony forming units for the fastest charge-converting NP as compared to both the slowest charge converter and free tobramycin. These studies provide a framework for the design of biofilm-penetrating NPs that respond to matrix interactions, ultimately increasing the efficacious delivery of antimicrobials.

Microfluidic Devices: A Tool for Nanoparticle Synthesis and Performance Evaluation

The use of nanoparticles (NPs) in nanomedicine holds great promise for the treatment of diseases for which conventional therapies present serious limitations. Additionally, NPs can drastically improve early diagnosis and follow-up of many disorders. However, to harness their full capabilities, they must be precisely designed, produced, and tested in relevant models. Microfluidic systems can simulate dynamic fluid flows, gradients, specific microenvironments, and multiorgan complexes, providing an efficient and cost-effective approach for both NPs synthesis and screening. Microfluidic technologies allow for the synthesis of NPs under controlled conditions, enhancing batch-to-batch reproducibility. Moreover, due to the versatility of microfluidic devices, it is possible to generate and customize endless platforms for rapid and efficient in vitro and in vivo screening of NPs' performance. Indeed, microfluidic devices show great potential as advanced systems for small organism manipulation and immobilization. In this review, first we summarize the major microfluidic platforms that allow for controlled NPs synthesis. Next, we will discuss the most innovative microfluidic platforms that enable mimicking in vitro environments as well as give insights into organism-on-a-chip and their promising application for NPs screening. We conclude this review with a critical assessment of the current challenges and possible future directions of microfluidic systems in NPs synthesis and screening to impact the field of nanomedicine.

The role of protein corona on nanodrugs for organ-targeting and its prospects of application

Nowadays, nanodrugs become a hotspot in the high-end medical field. They have the ability to deliver drugs to reach their destination more effectively due to their unique properties and flexible functionalization. However, the fate of nanodrugs in vivo is not the same as those presented in vitro, which indeed influenced their therapeutic efficacy in vivo. When entering the biological organism, nanodrugs will first come into contact with biological fluids and then be covered by some biomacromolecules, especially proteins. The proteins adsorbed on the surface of nanodrugs are known as protein corona (PC), which causes the loss of prospective organ-targeting abilities. Fortunately, the reasonable utilization of PC may determine the organ-targeting efficiency of systemically administered nanodrugs based on the diverse expression of receptors on cells in different organs. In addition, the nanodrugs for local administration targeting diverse lesion sites will also form unique PC, which plays an important role in the therapeutic effect of nanodrugs. This article introduced the formation of PC on the surface of nanodrugs and summarized the recent studies about the roles of diversified proteins adsorbed on nanodrugs and relevant protein for organ-targeting receptor through different administration pathways, which may deepen our understanding of the role that PC played on organ-targeting and improve the therapeutic efficacy of nanodrugs to promote their clinical translation.

Green Nanoformulations of Polyvinylpyrrolidone-Capped Metal Nanoparticles: A Study at the Hybrid Interface with Biomimetic Cell Membranes and In Vitro Cell Models

Noble metal nanoparticles (NP) with intrinsic antiangiogenic, antibacterial, and anti-inflammatory properties have great potential as potent chemotherapeutics, due to their unique features, including plasmonic properties for application in photothermal therapy, and their capability to slow down the migration/invasion speed of cancer cells and then suppress metastasis. In this work, gold (Au), silver (Ag), and palladium (Pd) NP were synthesized by a green redox chemistry method with the reduction of the metal salt precursor with glucose in the presence of polyvinylpyrrolidone (PVP) as stabilizing and capping agent. The physicochemical properties of the PVP-capped NP were investigated by UV-visible (UV-vis) and attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopies, dynamic light scattering (DLS), and atomic force microscopy (AFM), to scrutinize the optical features and the interface between the metal surface and the capping polymer, the hydrodynamic size, and the morphology, respectively. Biophysical studies with model cell membranes were carried out by using laser scanning confocal microscopy (LSM) with fluorescence recovery after photobleaching (FRAP) and fluorescence resonance energy transfer (FRET) techniques. To this purpose, artificial cell membranes of supported lipid bilayers (SLBs) made with 1-palmitoyl-2-oleoyl-sn-glycerol-3-phosphocholine (POPC) dye-labeled with 7-nitro-2-1,3-benzoxadiazol-4-yl (NBD, FRET donor) and/or lissamine rhodamine B sulfonyl (Rh, FRET acceptor) were prepared. Proof-of-work in vitro cellular experiments were carried out with prostate cancer cells (PC-3 line) in terms of cytotoxicity, cell migration (wound scratch assay), NP cellular uptake, and cytoskeleton actin perturbation.

Green Synthesis of Silver Nanoparticles Using the Leaf Extract of the Medicinal Plant, Uvaria narum and Its Antibacterial, Antiangiogenic, Anticancer and Catalytic Properties

Silver nanoparticles (AgNPs) made by green synthesis offer a variety of biochemical properties and are an excellent alternative to traditional medications due to their low cost. In the current study, we synthesised AgNPs from the leaf extract of the medicinal plant Uvaria narum, commonly called narumpanal. The nanoparticles were characterised by ultraviolet-visible (UV-Vis) spectroscopy, Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). SEM analysis showed AgNPs are highly crystalline and spherical with an average diameter of 7.13 nm. The outstanding catalytic activity of AgNPs was demonstrated by employing the reduction of 4-nitrophenol to 4-aminophenol. The AgNPs showed antiangiogenic activity in the chick chorioallantoic membrane (CAM) assay. AgNPs demonstrated anticancer activity against Dalton’s lymphoma ascites cells (DLA cells) in trypan blue assay and cytotoxicity against three fish cell lines: Oreochromis niloticus liver (onlL; National Repository of Fish Cell Lines, India (NRFC) Accession number—NRFC052) cells, Cyprinus carpio koi fin (CCKF; NRFC Accession number—NRFC007) cells and Cyprinus carpio gill (CyCKG; NRFC Accession number—NRFC064). Furthermore, the AgNPs demonstrated their ability to inhibit pathogenic microorganisms, Staphylococcus aureus, and Escherichia coli. The results from the study displayed green synthesised AgNPs exhibit antiangiogenic activity, cytotoxicity, antimicrobial and catalytic properties, which are crucial characteristics of a molecule with excellent clinical applications.

Advances in Engineered Biomaterials Targeting Angiogenesis and Cell Proliferation for Cancer Therapy

Antiangiogenic therapy in combination with chemotherapeutic agents is an effective strategy for cancer treatment. However, this combination therapy is associated with several challenges including non-specific biodistribution leading to systemic toxicity. Biomaterial-mediated codelivery of chemotherapeutic and anti-angiogenic agents can exploit their passive and active targeting abilities, leading to improved drug accumulation at the tumor site and therapeutic outcomes. In this review, we present the progress made in the field of engineered biomaterials for codelivery of chemotherapeutic and antiangiogenic agents. We present advances in engineering of liposome/hydrogel/micelle-based biomaterials for delivery of combination of anticancer and anti-angiogenesis drugs, or combination of anticancer and siRNA targeting angiogenesis, and targeted nanoparticles. We then present our perspective on developing strategies for targeting angiogenesis and cell proliferation for cancer therapy.

Effective treatment of intractable diseases using nanoparticles to interfere with vascular supply and angiogenic process

Angiogenesis is a vital biological process involving blood vessels forming from pre-existing vascular systems. This process contributes to various physiological activities, including embryonic development, hair growth, ovulation, menstruation, and the repair and regeneration of damaged tissue. On the other hand, it is essential in treating a wide range of pathological diseases, such as cardiovascular and ischemic diseases, rheumatoid arthritis, malignancies, ophthalmic and retinal diseases, and other chronic conditions. These diseases and disorders are frequently treated by regulating angiogenesis by utilizing a variety of pro-angiogenic or anti-angiogenic agents or molecules by stimulating or suppressing this complicated process, respectively. Nevertheless, many traditional angiogenic therapy techniques suffer from a lack of ability to achieve the intended therapeutic impact because of various constraints. These disadvantages include limited bioavailability, drug resistance, fast elimination, increased price, nonspecificity, and adverse effects. As a result, it is an excellent time for developing various pro- and anti-angiogenic substances that might circumvent the abovementioned restrictions, followed by their efficient use in treating disorders associated with angiogenesis. In recent years, significant progress has been made in different fields of medicine and biology, including therapeutic angiogenesis. Around the world, a multitude of research groups investigated several inorganic or organic nanoparticles (NPs) that had the potential to effectively modify the angiogenesis processes by either enhancing or suppressing the process. Many studies into the processes behind NP-mediated angiogenesis are well described. In this article, we also cover the application of NPs to encourage tissue vascularization as well as their angiogenic and anti-angiogenic effects in the treatment of several disorders, including bone regeneration, peripheral vascular disease, diabetic retinopathy, ischemic stroke, rheumatoid arthritis, post-ischemic cardiovascular injury, age-related macular degeneration, diabetic retinopathy, gene delivery-based angiogenic therapy, protein delivery-based angiogenic therapy, stem cell angiogenic therapy, and diabetic retinopathy, cancer that may benefit from the behavior of the nanostructures in the vascular system throughout the body. In addition, the accompanying difficulties and potential future applications of NPs in treating angiogenesis-related diseases and antiangiogenic therapies are discussed.

Detecting Defects in Composite Polymers by Using 3D Scanning Laser Doppler Vibrometry

The technique of 3D scanning laser Doppler vibrometry has recently appeared as a promising tool of nondestructive evaluation of discontinuity-like defects in composite polymers. The use of the phenomenon of local defect resonance (LDR) allows intensifying vibrations in defect zones, which can reliably be detected by means of laser vibrometry. The resonance acoustic stimulation of structural defects in materials causes compression/tension deformations, which are essentially lower than the material tensile strength, thus proving a nondestructive character of the LDR technique. In this study, the propagation of elastic waves in composites and their interaction with structural inhomogeneities were analyzed by performing 3D scanning of vibrations in Fast Fourier Transform mode. At each scanning point, the in-plane (x, y) and out of plane (z) vibration components were analyzed. The acoustic stimulation was fulfilled by generating a frequency-modulated harmonic signal in the range from 50 Hz to 100 kHz. In the case of a reference plate with a flat bottom hole, the resonance frequencies for all (x, y, and z) components were identical. In the case of impact damage in a carbon fiber reinforced plastic sample, the predominant contribution into total vibrations was provided by compression/tension deformations (x, y vibration component) to compare with vibrations by the z coordinate. In general, inspection results were enhanced by analyzing total vibration patterns obtained by averaging results at some resonance frequencies.

Nanoformulations - Insights Towards Characterization Techniques

BACKGROUND

Drug-loaded novel nanoformulations are gaining importance due to their versatile properties compared to conventional pharmaceutical formulations. Nanomaterials, apart from their multifactorial benefits, have a wider scope in the prevention, treatment, and diagnosis of cancer. Understanding the chemistry of drug-loaded nano-formulations to elicit its behaviour both at molecular and systemic levels is critical in the present scenario. Drug-loaded nanoformulations are controlled by their size, shape, surface chemistry, and release behavior. The major pharmaceutical drug loaded nanocarriers reported for anticancer drug delivery for the treatment of various forms of cancers such as lung cancer, liver cancer, breast cancer, colon cancer, etc include nanoparticles, nanospheres, nanodispersions, nanocapsules, nanomicelles, cubosomes, nanoemulsions, liposomes and niosomes. The major objectives in designing anticancer drug-loaded nanoformulations are to manage the particle size/morphology correlating with the drug release to fulfil the specific objectives. Hence, nano characterizations are very critical both at in vitro and in vivo levels.

OBJECTIVE

The main objective of this review paper is to summarise the major characterization techniques used for the characterization of drug-loaded nanoformulations. Even though information on characterization techniques of various nano-formulations is available in the literature, it is scattered. The proposed review will provide a comprehensive understanding of nanocharacterization techniques.

CONCLUSION

To conclude, the proposed review will provide insights towards the different nano characterization techniques along with their recent updates, such as particle size, zeta potential, entrapment efficiency, in vitro release studies (chromatographic HPLC, HPTLC, and LC-MS/MS analysis), EPR analysis, X-ray diffraction analysis, thermal analysis, rheometric, morphological analysis etc. Additionally, the challenges encountered by the nano characterization techniques will also be discussed.

Molecular and cellular effects of gold nanoparticles treatment in experimental diabetic myopathy

Background

This study aims to address the effects of gold nanoparticles (AuNPs) on diabetic myopathy in streptozotocin (STZ)-induced diabetic rats.

Materials and methods

Adult male rats were separated into three groups (n = 15): non-diabetic control (ND), diabetic (D), and diabetic treated with AuNPs (2.5 mg/kg, D + AuNPs) intraperitoneally for 4 weeks. A single injection of 50 mg/kg STZ was used to induce diabetes.

Results

Treatment with AuNPs lowered blood glucose levels. Skeletal muscle mRNA expression of two muscle-specific E3 ubiquitin-ligases enzymes, F-box-only protein 32 (FBXO32) and muscle RING-finger protein-1 (MuRF1) were upregulated in the D group. Diabetic rats showed significant increases in the skeletal muscle expression levels of plasminogen activator inhibitor-1 (PAI-1), tumor necrosis factor-α (TNF-α), transforming growth factor-β1 (TGF-β1), and a decrease in glucose transporter 4 (GLUT4) expression. Superoxide dismutase (SOD) activity decreased and malondialdehyde (MDA) level increased in skeletal muscles of D group. Compared to the D group, expression levels of FBXO32, MuRF1, PAI-1 TNF-α, and TGF-β1 were decreased in the D + AuNPs group, and mRNA of GLUT4 increased. Furthermore, in D + AuNPs group, skeletal muscle MDA levels decreased while SOD activity increased.

Conclusion

In experimental models, AuNPs can ameliorate muscle atrophy by reducing hyperglycemia, inflammation, and oxidative stress, and by suppressing the ubiquitin-proteasome proteolytic process.

Multimodal Potentials of Gold Nanoparticles for Bone Tissue Engineering and Regenerative Medicine: Avenues and Prospects

Osseous tissue repair has advanced due to the introduction of tissue engineering. The key elements required while engineering new tissues involve scaffolds, cells, and bioactive cues. The macrostructural to the nanostructural framework of such complex tissue has engrossed the intervention of nanotechnology for efficient neo-bone formation. Gold nanoparticles (GNPs) have recently gained interest in bone tissue regeneration due to their multimodal functionality. They are proven to modulate the properties of scaffolds and the osteogenic cells significantly. GNPs also influence different metabolic functions within the body, which directly or indirectly govern the mechanism of bone regeneration. Therefore, this review highlights nanoparticle-mediated osteogenic development, focusing on different aspects of GNPs ranging from scaffold modulation to cellular stimulation. The toxic aspects of gold nanoparticles studied so far are critically explicated, while further insight into the advancements and prospects of these nanoparticles in bone regeneration is also highlighted.

Disabling partners in crime: Gold nanoparticles disrupt multicellular communications within the tumor microenvironment to inhibit ovarian tumor aggressiveness

The tumor microenvironment (TME) plays a key role in the poor prognosis of many cancers. However, there is a knowledge gap concerning how multicellular communication among the critical players within the TME contributes to such poor outcomes. Using epithelial ovarian cancer (EOC) as a model, we show how crosstalk among cancer cells (CC), cancer associated fibroblasts (CAF), and endothelial cells (EC) promotes EOC growth. We demonstrate here that co-culturing CC with CAF and EC promotes CC proliferation, migration, and invasion in vitro and that co-implantation of the three cell types facilitates tumor growth in vivo. We further demonstrate that disruption of this multicellular crosstalk using a gold nanoparticle (GNP) inhibits these pro-tumorigenic phenotypes in vitro as well as tumor growth in vivo. Mechanistically, GNP treatment reduces expression of several tumor-promoting cytokines and growth factors, resulting in inhibition of MAPK and PI3K-AKT activation and epithelial-mesenchymal transition - three key oncogenic signaling pathways responsible for the aggressiveness of EOC. The current work highlights the importance of multicellular crosstalk within the TME and its role for the aggressive nature of EOC, and demonstrates the disruption of these multicellular communications by self-therapeutic GNP, thus providing new avenues to interrogate the crosstalk and identify key perpetrators responsible for poor prognosis of this intractable malignancy.

Pharmacological Role of Functionalized Gold Nanoparticles in Disease Applications

Gold has always been regarded as a symbol of nobility, and its shiny golden appearance has always attracted the attention of many people. Gold has good ductility, molecular recognition properties, and good biocompatibility. At present, gold is being used in many fields. When gold particles are as small as several nanometers, their physical and chemical properties vary with their size in nanometers. The surface area of a nano-sized gold surface has a special effect. Therefore, gold nanoparticles can, directly and indirectly, give rise to different biological activities. For example, if the surface of the gold is sulfided. Various substances have a strong chemical reactivity and are easy to combine with sulfhydryl groups; hence, nanogold is often used in biomedical testing, disease diagnosis, and gene detection. Nanogold is easy to bind to proteins, such as antibodies, enzymes, or cytokines. In fact, scientists use nanogold to bind special antibodies, as a tool for targeting cancer cells. Gold nanoparticles are also directly cytotoxic to cancer cells. For diseases caused by inflammation and oxidative damage, gold nanoparticles also have antioxidant and anti-inflammatory effects. Based on these unique properties, gold nanoparticles have become the most widely studied metal nanomaterials. Many recent studies have further demonstrated that gold nanoparticles are beneficial for humans, due to their functional pharmacological properties in a variety of diseases. The content of this review will be the application of gold nanoparticles in treating or diagnosing pressing diseases, such as cancers, retinopathy, neurological diseases, skin disorders, bowel diseases, bone cartilage disorders, cardiovascular diseases, infections, and metabolic syndrome. Gold nanoparticles have shown very obvious therapeutic and application potential.

Nanoparticles: Excellent Materials Yet Dangerous When They Become Airborne

Since the rise and rapid development of nanoscale science and technology in the late 1980s, nanomaterials have been widely used in many areas including medicine, electronic products, crafts, textiles, and cosmetics, which have provided a lot of convenience to people's life. However, while nanomaterials have been fully utilized, their negative effects, also known as nano pollution, have become increasingly apparent. The adverse effects of nanomaterials on the environment and organisms are mainly based on the unique size and physicochemical properties of nanoparticles (NPs). NPs, as the basic unit of nanomaterials, generally refer to the ultrafine particles whose spatial scale are defined in the range of 1-100 nm. In this review, we mainly introduce the basic status of the types and applications of NPs, airborne NP pollution, and the relationship between airborne NP pollution and human diseases. There are many sources of airborne NP pollutants, including engineered nanoparticles (ENPs) and non-engineered nanoparticles (NENPs). The NENPs can be further divided into those generated from natural activities and those produced by human activities. A growing number of studies have found that exposure to airborne NP pollutants can cause a variety of illnesses, such as respiratory diseases, cardiovascular diseases, and neurological disorders. To deal with the ever increasing numbers and types of NPs being unleashed to the air, we believe that extensive research is needed to provide a comprehensive understanding of NP pollution hazards and their impact mechanisms. Only in this way can we find the best solution and truly protect the safety and quality of life of human beings.

Immunomodulatory properties of nanostructured systems for cancer therapy

Based on statistical data reported in 2020, cancer was responsible for approximately 10 million deaths. Furthermore, 17 million new cases were diagnosed worldwide. Nanomedicine and immunotherapy have shown satisfactory clinical results among all scientific and technological alternatives for the treatment of cancer patients. Immunotherapy-based treatments comprise the consideration of new alternatives to hinder neoplastic proliferation and to reduce adverse events in the body, thereby promoting immune destruction of diseased cells. Additionally, nanostructured systems have been proven to elicit specific immune responses that may enhance anti-tumor activity. A new generation of nanomedicines, based on biomimetic and bioinspired systems, has been proposed to target tumors by providing immunomodulatory features and by enabling recovery of human immune destruction capacity against cancer cells. This review provides an overview of the aspects and the mechanisms by which nanomedicines can be used to enhance clinical procedures using the immune modulatory responses of nanoparticles (NPs) in the host defense system. We initially outline the cancer statistics for conventional and new treatment approaches providing a brief description of the human host defense system and basic principles of NP interactions with monocytes, leukocytes, and dendritic cells for the modulation of antitumor immune responses. A report on different biomimetic and bioinspired systems is also presented here and their particularities in cancer treatments are addressed, highlighting their immunomodulatory properties. Finally, we propose future perspectives regarding this new therapeutic strategy, highlighting the main challenges for future use in clinical practice.

New challenges in the use of nanomedicine in cancer therapy

Nanomedicines are applied as alternative treatments for anticancer agents. For the treatment of cancer, due to the small size in nanometers (nm), specific site targeting can be achieved with the use of nanomedicines, increasing their bioavailability and conferring fewer toxic side effects. Additionally, the use of minute amounts of drugs can lead to cost savings. In addition, nanotechnology is effectively applied in the preparation of such drugs as they are in nm sizes, considered one of the earliest cutoff values for the production of products utilized in nanotechnology. Early concepts described gold nanoshells as one of the successful therapies for cancer and associated diseases where the benefits of nanomedicine include effective active or passive targeting. Common medicines are degraded at a higher rate, whereas the degradation of macromolecules is time-consuming. All of the discussed properties are responsible for executing the physiological behaviors occurring at the following scale, depending on the geometry. Finally, large nanomaterials based on organic, lipid, inorganic, protein, and synthetic polymers have also been utilized to develop novel cancer cures.

Engineered strategies to enhance tumor penetration of drug-loaded nanoparticles

Nanocarriers have been widely employed in preclinical studies and clinical trials for the delivery of anticancer drugs. The most important causes of failure in clinical translation of nanocarriers is their inefficient accumulation and penetration which arises from special characteristics of tumor microenvironment such as insufficient blood supply, dense extracellular matrix, and elevated interstitial fluid pressure. Various strategies such as engineering extracellular matrix, optimizing the physicochemical properties of nanocarriers have been proposed to increase the depth of tumor penetration; however, these strategies have not been very successful so far. Novel strategies such as transformable nanocarriers, transcellular transport of peptide-modified nanocarriers, and bio-inspired carriers have recently been emerged as an advanced generation of drug carriers. In this study, the latest developments of nanocarrier-based drug delivery to solid tumor are presented with their possible limitations. Then, the prospects of advanced drug delivery systems are discussed in detail.

Alleviation of diabetic nephropathy by zinc oxide nanoparticles in streptozotocin-induced type 1 diabetes in rats

This study examines the effect of nanoparticles with zinc oxides (ZnONPs) on diabetic nephropathy, which is the primary cause of mortality for diabetic patients with end‐stage renal disease. Diabetes in adult male rats was induced via intraperitoneal injection of streptozotocin. ZnONPs were intraperitoneally administered to diabetic rats daily for 7 weeks. Diabetes was associated with increases in blood glucose level, 24‐h urinary albumin excretion rate, glomerular basement membrane thickness, renal oxidative stress markers, and renal mRNA or protein expression of transforming growth factor‐β1, fibronectin, collagen‐IV, tumour necrosis factor‐α and vascular endothelial growth factor‐A. Moreover, the expression of nephrin and podocin, and the mRNA expression of matrix metalloproteinase‐9 were decreased in the diabetic group. These changes were not detected in the control group and were significantly prevented by ZnONP treatment. These results provide evidence that ZnONPs ameliorate the renal damage induced in a diabetic rat model of nephropathy through improving renal functionality; inhibiting renal fibrosis, oxidative stress, inflammation and abnormal angiogenesis; and delaying the development of podocyte injury. The present findings may help design the clinical application of ZnONPs for protection against the development of diabetic nephropathy.

Nano-bio surface interactions, cellular internalisation in cancer cells and e-data portals of nanomaterials: A review

Nanomaterials (NMs) have abundant applications in areas such as electronics, energy, environment industries, biosensors, nano devices, theranostic platforms, etc. Nanoparticles can increase the solubility and stability of drug-loaded materials, enhance their internalisation, protect them from initial destruction in the biological system, and lengthen their circulation time. The biological interaction of proteins present in the body fluid with NMs can change the activity and natural surface properties of NMs. The size and charge of NMs, properties of the coated and uncoated NMs, nature of proteins, cellular interactions direct their internalisation pathway in the cellular system. Thus, the present review emphasises the impact of coated, uncoated NMs, size and charge, nature of proteins on nano-bio surface interactions and on internalisation with specific focus on cancer cells. The increased activity of NPs may also result in toxicity on health and environment, thus emphasis should be given to assess the toxicity of NMs in the medical field. The e-data sharing portals of NMs have also been discussed in this review that will be helpful in providing the information about the chemical, physical, biological properties and toxicity of NMs.

Tumor vasculature-targeting nanomedicines

Uncontrolled tumor growth and subsequent distant metastasis are highly dependent on an adequate nutrient supply from tumor blood vessels, which have relatively different pathophysiological characteristics from those of normal vasculature. Obviously, strategies targeting tumor vasculature, such as anti-angiogenic drugs and vascular disrupting agents, are attractive methods for cancer therapy. However, the off-target effects and high dose administration of these drug regimens critically restrict their clinical applications. In recent years, nanomedicines focused on tumor vasculature have been shown to be superior to traditional therapeutic methods and do not induce side effects. This review will first highlight the recent development of tumor vasculature-targeting nanomedicines from the following four aspects: 1) angiogenesis-inhibiting nanomedicines (AINs); 2) vasculature-disrupting nanomedicines (VDNs); 3) vasculature infarction nanomedicines (VINs); and 4) vasculature-regulating nanomedicines (VRNs). Furthermore, the design principles, limitations, and future directions are also discussed. STATEMENT OF SIGNIFICANCE: Based on the essential roles of tumor blood vessels, the therapeutic strategies targeting tumor vasculature have exhibited good clinical therapeutic outcomes. However, poor patient adherence to free drug administration limits their clinical usage. Nanomedicines have great potential to overcome the abovementioned obstacle. This review summarizes the tumor-vasculature targeting nanomedicines from four aspects: 1) angiogenesis-inhibiting nanomedicines (AINs); 2) vasculature-disrupting nanomedicines (VDNs); 3) vasculature infarction nanomedicines (VINs); and 4) vasculature regulating nanomedicines (VRNs). In addition, this review provides perspectives on this research field.

Effect on Human Vascular Endothelial Cells of Au Nanoparticles Synthesized from Vitex mollis

A green method for synthesizing gold nanoparticles is proposed using hydroethanolic extract of Vitex mollis fruit (Vm extract) as a reducer and stabilizer. The formation of gold nanoparticles synthesized with Vm extract (AuVmNPs) was monitored by measuring the ultraviolet-visible spectra. The morphology and crystalline phase were determined using scanning electron microscopy, X-ray diffraction, and high-resolution transmission electron microscopy. Synthesized nanoparticles were generally spherical, and the size distribution obtained by transmission electron microscopy shows two populations with mean sizes of 12.5 and 22.5 nm. Cell viability assay using MTT and cellular apoptosis studies using annexin V on human umbilical vein endothelial cells (HUVECs) and the human mammary epithelial cell line (MCF10A) indicate that AuVmNPs have low toxicity. Cell migration tests indicate that AuVmNPs significantly inhibit HUVEC cell migration in a dose-dependent manner. The evaluation of the localization of AuVmNPs in HUVECs using confocal laser scanning microscopy indicates that nanoparticles penetrate cells and are found in the cytosol without preferential distribution and without entering the nucleus. The inhibitory effect on cellular migration and low toxicity suggest AuVmNPs as appropriate candidates in future studies of antiangiogenic activity.

A Multifunctional Nanoplatform Made of Gold Nanoparticles and Peptides Mimicking the Vascular Endothelial Growth Factor

In this work, nanobiohybrids of plasmonic gold nanoparticles (AuNP, anti-angiogenic) and a peptide mimicking the vascular endothelial growth factor (VEGF, pro-angiogenic) were assembled and scrutinized in terms of physicochemical characterization, including optical properties, surface charge, surface chemical structure and morphology of the bioengineered metal nanoparticles, for their potential application as multifunctional theranostic (i.e., therapy + sensing) nanoplatform (AuNP/VEGF). Specifically, a peptide sequence encompassing the VEGF cellular receptor domain 73–101 (VEGF73–101) and its single point cysteine mutated were immobilized onto AuNP by physi- and chemi-sorption, respectively. The new hybrid systems were characterized by means of a multitechnique approach, including dynamic light scattering (DLS) analyses, zeta potential (ZP), spectroscopic (UV-Vis, FT-IR, XPS), spectrometric (TOF-SIMS) and microscopic (AFM, SEM) techniques. Proof-of-work cellular experiments in human umbilical vein endothelial cells (HUVEC) upon the treatment with AuNP/VEGF samples, demonstrated no toxicity up to 24 h (MTT assay) as well an effective internalization (laser confocal microscopy, LSM).

Gold Nanoparticles Affect Pericyte Biology and Capillary Tube Formation

Gold nanoparticles (AuNPs) are used for diagnostic and therapeutic purposes, especially antiangiogenesis, which are accomplished via inhibition of endothelial cell proliferation, migration, and tube formation. However, no research has been performed on the effects of AuNPs in pericytes, which play vital roles in endothelial cell functions and capillary tube formation during physiological and pathological processes. Therefore, the effects of AuNPs on the morphology and functions of pericytes need to be elucidated. This study treated human placental pericytes in monoculture with 20 nm AuNPs at a concentration of 30 ppm. Ki-67 and platelet-derived growth factor receptor-β (PDGFR-β) mRNA expression was measured using real-time reverse transcription-quantitative polymerase chain reaction (RT-qPCR). Cell migration was assessed by Transwell migration assay. The fine structures of pericytes were observed by transmission electron microscopy. In addition, 30 ppm AuNP-treated pericytes and intact human umbilical vein endothelial cells were cocultured on Matrigel to form three-dimensional (3D) capillary tubes. The results demonstrated that AuNPs significantly inhibited proliferation, reduced PDGFR-β mRNA expression, and decreased migration in pericytes. Ultrastructural analysis of pericytes revealed AuNPs in late endosomes, autolysosomes, and mitochondria. Remarkably, many mitochondria were swollen or damaged. Additionally, capillary tube formation was reduced. We found that numerous pericytes on 3D capillary tubes were round and did not extend their processes along the tubes, which resulted in more incomplete tube formation in the treatment group compared with the control group. In summary, AuNPs can affect pericyte proliferation, PDGFR-β mRNA expression, migration, morphology, and capillary tube formation. The findings highlight the possible application of AuNPs in pericyte-targeted therapy for antiangiogenesis.

BSA-Silver Nanoparticles: A Potential Multimodal Therapeutics for Conventional and Photothermal Treatment of Skin Cancer

Silver nanoparticles (NPs) have attracted a considerable interest in the field of cancer research due to their potential utility in cancer therapy. In the present study, we developed bovine serum albumin (BSA)-coated silver NPs (BSA-Silver NPs) and characterized in vitro multimodal therapeutic activities of NPs for the treatment of skin cancer. BSA-Silver NPs were synthesized by a single-step reduction process, and the successful preparation was verified through a list of physical characterizations, including transmission electron microscopy (TEM), ultraviolet-visible (UV–VIS) light spectroscopy, dynamic light scattering (DLS), and Fourier transform infrared (FT-IR) spectroscopy. The synthesized BSA-Silver NPs showed marked cytocidal effects on B16F10 melanoma cells, which was likely caused by oxidative stress. BSA-Silver NPs also elicited significant anti-angiogenic effects on HUVEC (human umbilical vein endothelial cell) by inhibiting their proliferation, migration, and tube formation. Moreover, BSA-Silver NPs showed a considerable light-to-heat conversion ability, suggesting their utility as photothermal agents. Overall, our findings suggest that BSA-Silver NPs may be promising candidates for the multimodal therapy of skin cancer.

Monotherapy and Combination Therapy Using Anti-Angiogenic Nanoagents to Fight Cancer

Anti-angiogenic therapy, targeting vascular endothelial cells (ECs) to prevent tumor growth, has been attracting increasing attention in recent years, beginning with bevacizumab (Avastin) through its Phase II/III clinical trials on solid tumors. However, these trials showed only modest clinical efficiency; moreover, anti-angiogenic therapy may induce acquired resistance to the drugs employed. Combining advanced drug delivery techniques (e.g., nanotechnology) or other therapeutic strategies (e.g., chemotherapy, radiotherapy, phototherapy, and immunotherapy) with anti-angiogenic therapy results in significantly synergistic effects and has opened a new horizon in fighting cancer. Herein, clinical difficulties in using traditional anti-angiogenic therapy are discussed. Then, several promising applications of anti-angiogenic nanoagents in monotherapies and combination therapies are highlighted. Finally, the challenges and perspectives of anti-angiogenic cancer therapy are summarized. A useful introduction to anti-angiogenic strategies, which may significantly improve therapeutic outcomes, is thus provided.

Synthesis and Antitumor Application of Antiangiogenetic Gold Nanoclusters

Conventional antiangiogenetic inhibitors suffered from poor delivery problems that result in unsatisfactory antitumor treatment efficacy. Although the liposomes or nanomaterial-based delivery systems can improve the therapeutic efficacy of antiangiogenic molecules, the assembly process is far too complex. Herein, a nanomaterial or a new nanodrug that could work without the help of a carrier and could be easily synthesized is needed. Au nanoclusters (AuNCs) are a kind of ideal nanostructures that could spontaneously enter into the cell and could be synthesized by a relatively easy one-pot method. Here, changing the traditional ligand glutathione (GSH) into an anti-Flt1 peptide (AF) has enriched the newly synthesized AF@AuNCs with targeted antiangiogenic properties. Based on the specific binding between AF and vascular endothelial growth factor receptor 1 (VEGFR1), the interaction between VEGFR1 and its ligands could be blocked. Furthermore, the expression of VEGFR2 could be downregulated. Compared with pure AF peptide- and GSH-participated AuNCs (GSH@AuNCs), AF@AuNCs were more effective in inhibiting both tube formation and migration of the endothelial cells in vitro. Furthermore, the in vivo chick embryo chorioallantoic membrane (CAM) experiment and antitumor experiment were conducted to further verify the enhanced antiangiogenesis and tumor inhibition effect of AF@AuNCs. Our findings provide promising evidence of a carrier-free nanodrug for tumors and other vascular hyperproliferative diseases.

ROS-Mediated Apoptosis and Autophagy in Ovarian Cancer Cells Treated with Peanut-Shaped Gold Nanoparticles

Background

Even with considerable improvement in treatment of epithelial ovarian cancer achieved in recent years, an increasing chemotherapy resistance and disease 5-year relapse is recorded for a majority part of patients that encourages the search for better therapeutic options. Gold nanoparticles (Au NPs) due to plethora of unique physiochemical features are thoroughly tested as drug delivery, radiosensitizers, as well as photothermal and photodynamic therapy agents. Importantly, due to highly controlled synthesis, it is possible to obtain nanomaterials with directed size and shape.

Methods

In this work, we developed novel elongated-type gold nanoparticles in the shape of nanopeanuts (AuP NPs) and investigated their cytotoxic potential against ovarian cancer cells SKOV-3 using colorimetric and fluorimetric methods, Western blot, flow cytometry, and fluorescence microscopy.

Results

Peanut-shaped gold nanoparticles showed high anti-cancer activity in vitro against SKOV-3 cells at doses of 1–5 ng/mL upon 72 hours treatment. We demonstrate that AuP NPs decrease the viability and proliferation capability of ovarian cancer cells by triggering cell apoptosis and autophagy, as evidenced by flow cytometry and Western blot analyses. The overproduction of reactive oxygen species (ROS) was noted to be a critical mediator of AuP NPs-mediated cell death.

Conclusion

These data indicate that gold nanopeanuts might be developed as nanotherapeutics against ovarian cancer.

Cellular Uptake, Organelle Enrichment, and In Vitro Antioxidation of Fullerene Derivatives, Mediated by Surface Charge

Hydrophilic fullerene derivatives get notable performance in various biological applications, especially in cancer therapy and antioxidation. The biological behaviors of functional fullerenes are much dependent on their surface physicochemical properties. The excellent reactive oxygen species-scavenging capabilities of functional fullerenes promote their outstanding performances in inhibiting pathological symptoms associated with oxidative stress, including neurodegenerative diseases, cardiovascular diseases, acute and chronic kidney disease, and diabetes. Herein, fullerene derivatives with reversed surface charges in aqueous solutions are prepared: cationic C₆₀-EDA and anionic C₆₀-(EDA-EA). Under the driving force of membrane potential (negative inside) in the cell and mitochondria, C₆₀-EDA is much rapidly taken in by cells and transported into mitochondria compared with C₆₀-(EDA-EA) that is enriched in lysosomes. With high cellular uptake and mitochondrial enrichment, C₆₀-EDA exhibits stronger antioxidation capabilities in vitro than C₆₀-(EDA-EA), indicating its better performance in the therapy of oxidation-induced diseases. It is revealed that the cellular uptake rate, subcellular location, and intracellular antioxidation behavior of fullerene derivatives are primarily mediated by their surface charges, providing new strategies for the design of fullerene drugs and their biological applications.

Intracellular and extracellular targets as mechanisms of cancer therapy by nanomaterials in relation to their physicochemical properties

Cancer nanomedicine has evolved in recent years and is only expected to increase due to the ease with which nanomaterials (NMs) may be manipulated to the advantage of the cancer patient. The success of nanomedicine is dependent on the cell death mechanism, which in turn is dependent on the organelle initially targeted. The success of cancer nanomedicine is also dependent on other cellular mechanisms such as the induction of autophagy dysfunction, manipulation of the tumor microenvironment (TME) and secretome or induction of host immune responses. Current cancer phototherapies for example, photothermal- or photodynamic therapies as well as radio enhancement also form a major part of cancer nanomedicine. In general, cancer nanomedicine may be grouped into those NMs exhibiting inherent anti-cancer properties that is, self-therapeutic NMs (Group 1), NMs leading to localization of phototherapies or radio-enhancement (Group 2), and NMs as nanocarriers in the absence or presence of external radiation (Group 3). The recent advances of these three groups, together with their advantages and disadvantages as well as their cellular mechanisms and ultimate outcomes are summarized in this review. By exploiting these different intracellular mechanisms involved in initiating cell death pathways, it is possible to synthesize NMs that may have the desirable characteristics to maximize their efficacy in cancer therapy. Therefore, a summary of these important physicochemical characteristics is also presented that need to be considered for optimal cancer cell targeting and initiation of mechanisms that will lead to cancerous cell death. This article is categorized under: Therapeutic Approaches and Drug Discovery > Nanomedicine for Oncologic Disease Toxicology and Regulatory Issues in Nanomedicine > Toxicology of Nanomaterials Toxicology and Regulatory Issues in Nanomedicine > Regulatory and Policy Issues in Nanomedicine.

Gold nanoparticles inhibit activation of cancer-associated fibroblasts by disrupting communication from tumor and microenvironmental cells

Cancer-associated fibroblasts (CAFs) are a major constituent of the tumor microenvironment (TME) and an important contributor to cancer progression and therapeutic resistance. Regulation of CAF activation is a promising strategy to influence cancer outcomes. Here, we report that ovarian cancer cells (OCs) and TME cells promote the activation of ovarian CAFs, whereas gold nanoparticles (GNPs) of 20 nm in diameter inhibit the activation, as demonstrated by the changes in cell morphology, migration, and molecular markers. GNPs exert the effect by altering the levels of multiple fibroblast activation or inactivation proteins, such as TGF-β1, PDGF, uPA and TSP1, secreted by OCs and TME cells. Thus, GNPs represent a potential tool to help understand multicellular communications existing in the TME as well as devise strategies to disrupt the communication.

Smart nano-micro platforms for ophthalmological applications: The state-of-the-art and future perspectives

Smart nano-micro platforms have been extensively applied for diverse biomedical applications, mostly focusing on cancer therapy. In comparison with conventional nanotechnology, the smart nano-micro matrix can exhibit specific response to exogenous or endogenous triggers, and thus can achieve multiple functions e.g. site-specific drug delivery, bio-imaging and detection of bio-molecules. These intriguing techniques have expanded into ophthalmology in recent years, yet few works have been summarized in this field. In this work, we provide the state-of-the-art of diverse nano-micro platforms based on both the conventional materials (e.g. natural or synthetic polymers, lipid nanomaterials, metal and metal oxide nanoparticles) and emerging nanomaterials (e.g. up-conversion nanoparticles, quantum dots and carbon materials) in ophthalmology, with some smart nano/micro platformers highlighted. The common ocular diseases studied in the field of nano-micro systems are firstly introduced, and their therapeutic method and the related drawback in clinic treatment are presented. The recent progress of different materials for diverse ocular applications is then demonstrated, with the representative nano- and micro-systems highlighted in detail. At last, an in-depth discussion on the clinical translation challenges faced in this field and the future direction are provided. This review would allow the researchers to design more smart nanomedicines in a more rational manner for specific ophthalmology applications.

The application of nanoparticles in cancer immunotherapy: Targeting tumor microenvironment

The tumor development and metastasis are closely related to the structure and function of the tumor microenvironment (TME). Recently, TME modulation strategies have attracted much attention in cancer immunotherapy. Despite the preliminary success of immunotherapeutic agents, their therapeutic effects have been restricted by the limited retention time of drugs in TME. Compared with traditional delivery systems, nanoparticles with unique physical properties and elaborate design can efficiently penetrate TME and specifically deliver to the major components in TME. In this review, we briefly introduce the substitutes of TME including dendritic cells, macrophages, fibroblasts, tumor vasculature, tumor-draining lymph nodes and hypoxic state, then review various nanoparticles targeting these components and their applications in tumor therapy. In addition, nanoparticles could be combined with other therapies, including chemotherapy, radiotherapy, and photodynamic therapy, however, the nanoplatform delivery system may not be effective in all types of tumors due to the heterogeneity of different tumors and individuals. The changes of TME at various stages during tumor development are required to be further elucidated so that more individualized nanoplatforms could be designed.

Designer nanocarriers for navigating the systemic delivery of oncolytic viruses

Nanotechnology is paving the way for new carrier systems designed to overcome the greatest challenges of oncolytic virotherapy; systemic administration and subsequent implications of immune responses and specific cell binding and entry. Systemic administration of oncolytic agents is vital for disseminated neoplasms, however transition of nanoparticles (NP) to virotherapy has yielded modest results. Their success relies on how they navigate the merry-go-round of often-contradictory phases of NP delivery: circulatory longevity, tissue permeation and cellular interaction, with many studies postulating design features optimal for each phase. This review discusses the optimal design of NPs for the transport of oncolytic viruses within these phases, to determine whether improved virotherapeutic efficacy lies in the pharmacokinetic/pharmacodynamics characteristics of the NP-oncolytic viruses complexes rather than manipulation of the virus and targeting ligands.

Urban PM2.5 reduces angiogenic ability of endothelial cells in an alveolar-capillary co-culture lung model

Adverse health effects arising from exposure to fine particulates have become a major concern. Angiogenesis is a vital physiological process for the growth and development of cells and structures in the human body, whereby excessive or insufficient vessel growth could contribute to pathogenesis of diseases. We therefore evaluated indirect effects of carbon black (CB) and inhalable airborne particles on the angiogenic ability of unexposed Human Umbilical Vein Endothelial Cells (HUVECs) by co-culturing HUVECs with pre-exposed Small Airway Epithelial Cells (SAECs). As endothelial cells are major components of blood vessels and potential targets of fine particles, we investigated if lung epithelial cells exposed to ambient PM_2.5 surrogates could induce bystander effects on neighboring unexposed endothelial cells in an alveolar-capillary co-culture lung model. Epithelial exposure to CB at a non-toxic dose of 25 μg/mL reduced endothelial tube formation and cell adhesion in co-cultured HUVECs, and decreased expression of angiogenic genes in SAECs. Similarly, exposure of differentiated SAECs to PM_2.5 surrogates reduced cell reproductive ability, adhesion and tube formation of neighboring HUVECs. This indicates epithelial exposure to CB and urban PM_2.5 surrogates both compromised the angiogenic ability of endothelial cells through bystander effects, thereby potentially perturbing the ventilation-perfusion ratio and affecting lung function.

Gold Nanoparticles Induce Tumor Vessel Normalization and Impair Metastasis by Inhibiting Endothelial Smad2/3 Signaling

Gold nanoparticles (AuNPs) are a promising nanomaterial due to their drug-delivery properties and inherent anti-neoplastic activity. Here, we focused on the anti-neoplastic effects of an improved targeting polymer and folic acid-modified gold nanoparticles (AuNPP-FA) without therapeutic drugs. AuNPP-FA inhibited tumor proliferation both in vitro and in vivo, and tumor metastasis was controlled in vivo. We also found that, in addition to inhibiting tumor angiogenesis, AuNPP-FA normalized tumor vasculature by increasing pericyte coverage and strengthening tight junctions by upregulating VE-cadherin (VE-cad) levels on endothelial cells. This decreased vascular permeability, improved vascular perfusion, and alleviated tissue hypoxia. The immunotherapeutic response was enhanced due to the increased infiltration of CD3⁺CD8⁺ T lymphocytes. AuNPP-FA increased the expression and secretion of semaphorin 3A (SEMA3A) in cancer cells to further inhibit Smad2/3 signaling in human umbilical vein endothelial cells (HUVECs). This normalized tumor vasculature and inhibited metastasis. In conclusion, AuNPP-FA normalized tumor vasculature; therefore, AuNPP-FA has great potential for future clinical applications.