Biosynthesis of selenium nanoparticles, characterization and X-ray induced radiotherapy for the treatment of lung cancer with interstitial lung disease

Deciphering the Mechanisms and Biotechnological Implications of Nanoparticle Synthesis Through Microbial Consortia

Nanomaterial synthesis is a growing study area because of its extensive range of uses. Nanoparticles' high surface-to-volume ratio and rapid interaction with various particles make them appealing for diverse applications. Traditional physical and chemical methods for creating metal nanoparticles are becoming outdated because they involve complex manufacturing processes, high energy consumption, and the formation of harmful by-products that pose major dangers to human health and the environment. Therefore, there is an increasing need to find alternative, cost-effective, dependable, biocompatible, and environmentally acceptable ways of producing nanoparticles. The process of synthesizing nanoparticles using microbes has become highly intriguing because of their ability to create nanoparticles of varying sizes, shapes, and compositions, each with unique physicochemical properties. Microbes are commonly used in nanoparticle production because they are easy to work with, can use low-cost materials, such as agricultural waste, are cheap to scale up, and can adsorb and reduce metal ions into nanoparticles through metabolic activities. Biogenic synthesis of nanoparticles provides a clean, nontoxic, ecologically friendly, and sustainable method using renewable ingredients for reducing metals and stabilizing nanoparticles. Nanomaterials produced by bacteria can serve as an effective pollution control method due to their many functional groups that can effectively target contaminants for efficient bioremediation, aiding in environmental cleanup. At the end of the paper, we will discuss the obstacles that hinder the use of biosynthesized nanoparticles and microbial-based nanoparticles. The paper aims to explore the sustainability of microorganisms in the burgeoning field of green nanotechnology.

Effect of Selenium and Selenoproteins on Radiation Resistance

With the advancement of radiological medicine and nuclear industry technology, radiation is increasingly used to diagnose human health disorders. However, large-scale nuclear leakage has heightened concerns about the impact on human organs and tissues. Selenium is an essential trace element that functions in the body mainly in the form of selenoproteins. Selenium and selenoproteins can protect against radiation by stimulating antioxidant actions, DNA repair functions, and immune enhancement. While studies on reducing radiation through antioxidants have been conducted for many years, the underlying mechanisms of selenium and selenoproteins as significant antioxidants in radiation damage mitigation remain incompletely understood. Therefore, this paper aims to provide new insights into developing safe and effective radiation protection agents by summarizing the anti-radiation mechanism of selenium and selenoproteins.

The Promising Role of Selenium and Yeast in the Fight Against Protein Amyloidosis

In recent years, increasing attention has been paid to research on diseases related to the deposition of misfolded proteins (amyloids) in various organs. Moreover, modern scientists emphasise the importance of selenium as a bioelement necessary for the proper functioning of living organisms. The inorganic form of selenium-sodium selenite (redox-active)-can prevent the formation of an insoluble polymer in proteins. It is very important to undertake tasks aimed at understanding the mechanisms of action of this element in inhibiting the formation of various types of amyloid. Furthermore, yeast cells play an important role in this matter as a eukaryotic model organism, which is intensively used in molecular research on protein amyloidosis. Due to the lack of appropriate treatment in the general population, the problem of amyloidosis remains unsolved. This extracellular accumulation of amyloid is one of the main factors responsible for the occurrence of Alzheimer's disease. The review presented here contains scientific information discussing a brief description of the possibility of amyloid formation in cells and the use of selenium as a factor preventing the formation of these protein aggregates. Recent studies have shown that the yeast model can be successfully used as a eukaryotic organism in biotechnological research aimed at understanding the essence of the entire amyloidosis process. Understanding the mechanisms that regulate the reaction of yeast to selenium and the phenomenon of amyloidosis is important in the aetiology and pathogenesis of various disease states. Therefore, it is imperative to conduct further research and analysis aimed at explaining and confirming the role of selenium in the processes of protein misfolding disorders. The rest of the article discusses the characteristics of food protein amyloidosis and their use in the food industry. During such tests, their toxicity is checked because not all food proteins can produce amyloid that is toxic to cells. It should also be noted that a moderate diet is beneficial for the corresponding disease relief caused by amyloidosis.

Application of nano-radiosensitizers in non-small cell lung cancer

Radiotherapy stands as a cornerstone in the treatment of numerous malignant tumors, including non-small cell lung cancer. However, the critical challenge of amplifying the tumoricidal effectiveness of radiotherapy while minimizing collateral damage to healthy tissues remains an area of significant research interest. Radiosensitizers, by methods such as amplifying DNA damage and fostering the creation of free radicals, play a pivotal role in enhancing the destructive impact of radiotherapy on tumors. Over recent decades, nano-dimensional radiosensitizers have emerged as a notable advancement. Their mechanisms include cell cycle arrest in the G2/M phase, combating tumor hypoxia, and others, thereby enhancing the efficacy of radiotherapy. This review delves into the evolving landscape of nanomaterials used for radiosensitization in non-small cell lung cancer. It provides insights into the current research progress and critically examines the challenges and future prospects within this burgeoning field.

Anti-breast cancer activity of biosynthesized selenium nanoparticles using Bacillus coagulans supernatant

BACKGROUND

In the present study, Selenium Nanoparticles (SeNPs) were prepared using Bacillus coagulans, which is a type of Lactic Acid Bacteria (LAB), and then they were applied to treat breast cancer cells.

METHODS

The chemicophysical properties of the bioengineered SeNPs were investigated by Transmission Electron Microscopy (TEM), Field Emission Scanning Electron Microscopy (FE-SEM), zeta potential, dynamic light scattering, Fourier Transform Infrared Spectroscopy (FT-IR), energy dispersive X-ray spectroscopy (EDX) and X-ray diffraction analysis (XRD). The cytotoxic potential of SeNPs was evaluated by MTT assay against MCF-7 breast cancer cell line. The expression levels of apoptotic genes including BAX, BCL2, VEGF, ERBB2, CASP3, CASP9, CCNE1, CCND1, MMP2 and MMP9 were determined by real-time PCR. The rate of apoptosis and necrosis of the cancer cells as well as the results of the cell cycle were evaluated by flow cytometry method.

RESULTS

The synthesized SeNPs had an average particle size of about 24-40 nm and a zeta potential of -16.1 mV, indicating the high stability of SeNPs. EDX results showed presence of SeNPs because amount of selenium in SeNPs was 86.6 % by weight. The cytotoxicity results showed a concentration-dependent effect against MCF-7 cells. The half-maximal inhibitory concentration (IC50) values of B. coagulans supernatant and SeNPs against breast cancer cells were 389.7 µg/mL and 17.56 µg/mL, respectively. In addition, SeNPs synthesized by the green process exhibited enhanced apoptotic potential in MCF-7 cancer cells compared with bacterial supernatants. Cancer cells treated with IC50 concentration of SeNPs induced 32 % apoptosis compared to untreated cells (3 % apoptosis). The gene expression levels of BAX, CASP3, and CASP9 were upregulated, while the expression levels of BCL2, CCNE1, CCND1, MMP2, MMP9, VEGF, and ERBB2 were downregulated after SeNPs treatment of cells. The potential of SeNPs to induce cell apoptosis was demonstrated by the increase in the expression level of BAX gene and the decrease in the expression level of BCL2 after treatment of cancer cells with SeNPs.

CONCLUSION

The obtained results indicated that SeNPs had strong potential to induce significant cell apoptosis and are cytotoxic against the MCF-7 cancer cell line.

Enhanced Induction of Apoptosis and Cell Cycle Arrest in MCF-7 Breast Cancer and HT-29 Colon Cancer Cell Lines via Low-Dose Biosynthesis of Selenium Nanoparticles Utilizing Lactobacillus casei

As a leading global cause of mortality, cancer continues to pose a significant challenge. The shortcomings of prevalent cancer treatments, such as surgery, radiation therapy, and chemotherapy, necessitate the exploration of alternative therapeutic strategies. Selenium nanoparticles (SeNPs) have emerged as a promising solution, with their synthesis being widely researched due to their potential applications. Among the diverse synthesis methods for SeNPs, the green chemistry approach holds a distinctive position within nanotechnology. This research delves into the anti-proliferative and anticancer properties of green-synthesized SeNPs via the cell-free supernatant (CFS) of Lactobacillus casei (LC-SeNPs), with a specific focus on MCF-7 and HT-29 cancer cell lines. SeNPs were synthesized employing the supernatant of L. casei. The characterization of these green-synthesized SeNPs was performed using TEM, FE-SEM, XRD, FT-IR, UV-vis, energy-dispersive X-ray spectroscopy, and DLS. The biological impact of LC-SNPs on MCF-7 and HT-29 cancer cells was examined via MTT, flow cytometry, scratch tests, and qRT-PCR. Both FE-SEM and TEM images substantiated the spherical shape of the synthesized nanoparticles. The biosynthesized LC-SNPs reduced the survival of MCF-7 (by 20%) and HT-29 (by 30%) cells at a concentration of 100 μg/mL. Flow cytometry revealed that LC-SNPs were capable of inducing 28% and 23% apoptosis in MCF-7 and HT-29 cells, respectively. In addition, it was found that LC-SNPs treated MCF-7 and HT-29 cells were arrested in the sub-G1 phase. Gene expression analysis indicated that the expression levels of the CASP3, CASP9, and BAX genes were elevated after treating MCF-7 and HT-29 cells with LC-SNPs. Further, SeNPs were observed to inhibit migration and invasion of MCF-7 and HT-29 cancer cells. The SeNPs, produced via L. casei, demonstrated strong anticancer effects on MCF-7 and HT-29 cells, suggesting their potential as biological agents in cancer treatment following additional in vivo experiments.

Mycosynthesis of selenium nanoparticles using Penicillium tardochrysogenum as a therapeutic agent and their combination with infrared irradiation against Ehrlich carcinoma

Over the past years, the assessment of myco-fabricated selenium nanoparticles (SeNPs) properties, is still in its infancy. Herein, we have highly stable myco-synthesized SeNPs using molecularly identified soil-isolated fungus; Penicillium tardochrysogenum OR059437; (PeSeNPs) were clarified via TEM, EDX, UV-Vis spectrophotometer, FTIR and zeta potential. The therapeutic efficacy profile will be determined, these crystalline PeSeNPs were examined for antioxidant, antimicrobial, MIC, and anticancer potentials, indicating that, PeSeNPs have antioxidant activity of (IC50, 109.11 μg/mL) using DPPH free radical scavenging assay. Also, PeSeNPs possess antimicrobial potential against Penicillium italicum RCMB 001,018 (1) IMI 193,019, Methicillin-Resistant Staphylococcus aureus (MRSA) ATCC 4330 and Porphyromonas gingivalis RCMB 022,001 (1) EMCC 1699; with I.Z. diameters and MIC; 16 ± 0.5 mm and MIC 500 µg/ml, 11.9 ± 0.6 mm, 500 µg/ml and 15.9±0.6 mm, 1000 µg/ml, respectively. Additionally, TEM micrographs were taken for P. italicum treated with PeSeNPs, demonstrating the destruction of hyphal membrane and internal organelles integrity, pores formation, and cell death. PeSeNP alone in vivo and combined with a near-infrared physiotherapy lamp with an energy intensity of 140 mW/cm2 showed a strong therapeutic effect against cancer cells. Thus, PeSeNPs represent anticancer agents and a suitable photothermal option for treating different kinds of cancer cells with lower toxicity and higher efficiency than normal cells. The combination therapy showed a very large and significant reduction in tumor volume, the tumor cells showed large necrosis, shrank, and disappeared. There was also improvement in liver ultrastructure, liver enzymes, and histology, as well as renal function, urea, and creatinine.

Biogenic selenium nanoparticles and selenium/chitosan-Nanoconjugate biosynthesized by Streptomyces parvulus MAR4 with antimicrobial and anticancer potential

BACKGROUND

As antibiotics and chemotherapeutics are no longer as efficient as they once were, multidrug resistant (MDR) pathogens and cancer are presently considered as two of the most dangerous threats to human life. In this study, Selenium nanoparticles (SeNPs) biosynthesized by Streptomyces parvulus MAR4, nano-chitosan (NCh), and their nanoconjugate (Se/Ch-nanoconjugate) were suggested to be efficacious antimicrobial and anticancer agents.

RESULTS

SeNPs biosynthesized by Streptomyces parvulus MAR4 and NCh were successfully achieved and conjugated. The biosynthesized SeNPs were spherical with a mean diameter of 94.2 nm and high stability. Yet, Se/Ch-nanoconjugate was semispherical with a 74.9 nm mean diameter and much higher stability. The SeNPs, NCh, and Se/Ch-nanoconjugate showed significant antimicrobial activity against various microbial pathogens with strong inhibitory effect on their tested metabolic key enzymes [phosphoglucose isomerase (PGI), pyruvate dehydrogenase (PDH), glucose-6-phosphate dehydrogenase (G6PDH) and nitrate reductase (NR)]; Se/Ch-nanoconjugate was the most powerful agent. Furthermore, SeNPs revealed strong cytotoxicity against HepG2 (IC50 = 13.04 μg/ml) and moderate toxicity against Caki-1 (HTB-46) tumor cell lines (IC50 = 21.35 μg/ml) but low cytotoxicity against WI-38 normal cell line (IC50 = 85.69 μg/ml). Nevertheless, Se/Ch-nanoconjugate displayed substantial cytotoxicity against HepG2 and Caki-1 (HTB-46) with IC50 values of 11.82 and 7.83 μg/ml, respectively. Consequently, Se/Ch-nanoconjugate may be more easily absorbed by both tumor cell lines. However, it exhibited very low cytotoxicity on WI-38 with IC50 of 153.3 μg/ml. Therefore, Se/Ch-nanoconjugate presented the most anticancer activity.

CONCLUSION

The biosynthesized SeNPs and Se/Ch-nanoconjugate are convincingly recommended to be used in biomedical applications as versatile and potent antimicrobial and anticancer agents ensuring notable levels of biosafety, environmental compatibility, and efficacy.

Selenium Nanoparticles: Green Synthesis and Biomedical Application

Selenium nanoparticles (SeNPs) are extremely popular objects in nanotechnology. "Green" synthesis has special advantages due to the growing necessity for environmentally friendly, non-toxic, and low-cost methods. This review considers the biosynthesis mechanism of bacteria, fungi, algae, and plants, including the role of various biological substances in the processes of reducing selenium compounds to SeNPs and their further packaging. Modern information and approaches to the possible biomedical use of selenium nanoparticles are presented: antimicrobial, antiviral, anticancer, antioxidant, anti-inflammatory, and other properties, as well as the mechanisms of these processes, that have important potential therapeutic value.

Hyaluronic acid-empowered nanotheranostics in breast and lung cancers therapy

Nanomedicine application in cancer therapy is an urgency because of inability of current biological therapies for complete removal of tumor cells. The development of smart and novel nanoplatforms for treatment of cancer can provide new insight in tumor suppression. Hyaluronic acid is a biopolymer that can be employed for synthesis of smart nanostructures capable of selective targeting CD44-overexpressing tumor cells. The breast and lung cancers are among the most malignant and common tumors in both females and males that environmental factors, lifestyle and genomic alterations are among the risk factors for their pathogenesis and development. Since etiology of breast and lung tumors is not certain and multiple factors participate in their development, preventative measures have not been completely successful and studies have focused on developing new treatment strategies for them. The aim of current review is to provide a comprehensive discussion about application of hyaluronic acid-based nanostructures for treatment of breast and lung cancers. The main reason of using hyaluronic acid-based nanoparticles is their ability in targeting breast and lung cancers in a selective way due to upregulation of CD44 receptor on their surface. Moreover, nanocarriers developed from hyaluronic acid or functionalized with hyaluronic acid have high biocompatibility and their safety is appreciated. The drugs and genes used for treatment of breast and lung cancers lack specific accumulation at cancer site and their cytotoxicity is low, but hyaluronic acid-based nanostructures provide their targeted delivery to tumor site and by increasing internalization of drugs and genes in breast and lung tumor cells, they improve their therapeutic index. Furthermore, hyaluronic acid-based nanostructures can be used for phototherapy-mediated breast and lung cancers ablation. The stimuli-responsive and smart kinds of hyaluronic acid-based nanostructures such as pH- and light-responsive can increase selective targeting of breast and lung cancers.

Potential Applications of Nanoparticles in Improving the Outcome of Lung Cancer Treatment

Lung cancer is managed using conventional therapies, including chemotherapy, radiation therapy, or a combination of both. Each of these therapies has its own limitations, such as the indiscriminate killing of normal as well as cancer cells, the solubility of the chemotherapeutic drugs, rapid clearance of the drugs from circulation before reaching the tumor site, the resistance of cancer cells to radiation, and over-sensitization of normal cells to radiation. Other treatment modalities include gene therapy, immunological checkpoint inhibitors, drug repurposing, and in situ cryo-immune engineering (ICIE) strategy. Nanotechnology has come to the rescue to overcome many shortfalls of conventional therapies. Some of the nano-formulated chemotherapeutic drugs, as well as nanoparticles and nanostructures with surface modifications, have been used for effective cancer cell killing and radio sensitization, respectively. Nano-enabled drug delivery systems act as cargo to deliver the sensitizer molecules specifically to the tumor cells, thereby enabling the radiation therapy to be more effective. In this review, we have discussed the different conventional chemotherapies and radiation therapies used for inhibiting lung cancer. We have also discussed the improvement in chemotherapy and radiation sensitization using nanoparticles.

Pharmacological Prospects of Morin Conjugated Selenium Nanoparticles-Evaluation of Antimicrobial, Antioxidant, Thrombolytic, and Anticancer Activities

Abstract

Selenium nanoparticles (SeNPs) have gained wide importance in the scientific community and have emerged as an optimistic therapeutic carrier agent for targeted drug delivery. In the present study, the effectiveness of nano selenium conjugated with Morin (Ba-SeNp-Mo) produced from endophytic bacteria Bacillus endophyticus reported in our earlier research was tested against various Gram-positive, Gram-negative bacterial pathogens and fungal pathogens that showed good zone of inhibition against all selected pathogens. Antioxidant activities of these NPs were studied by 1, 1-diphenyl-2- picrylhydrazyl (DPPH), 2,2'-Azino-bis-3-ethylbenzothiozoline-6-sulfonic acid (ABTS), hydrogen peroxide (H2O2), superoxide (O2-), and nitric oxide (NO) radical scavenging assays that exhibited dose-dependent free radical scavenging activity with IC50 values 6.92 ± 1.0, 16.85 ± 1.39, 31.60 ± 1.36, 18.87 ± 1.46, and 6.95 ± 1.27 μg/mL. The efficiency of DNA cleavage and thrombolytic activity of Ba-SeNp-Mo were also studied. The antiproliferative effect of Ba-SeNp-Mo was determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay in COLON-26 cell lines that resulted in IC50 value of 63.11 μg/mL. Further increased intracellular reactive oxygen species (ROS) levels up to 2.03 and significant early, late and necrotic cells were also observed in AO/EtBr assay. CASPASE 3 expression was upregulated to 1.22 (40 μg/mL) and 1.85 (80 μg/mL) fold. Thus, the current investigation suggested that the Ba-SeNp-Mo has offered remarkable pharmacological activity.

Graphical Abstract

Theranostic applications of selenium nanomedicines against lung cancer

The incidence and mortality rates of lung cancer are among the highest in the world. Traditional treatment methods include surgery, chemotherapy, and radiotherapy. Although rapid progress has been achieved in the past decade, treatment limitations remain. It is therefore imperative to identify safer and more effective therapeutic methods, and research is currently being conducted to identify more efficient and less harmful drugs. In recent years, the discovery of antitumor drugs based on the essential trace element selenium (Se) has provided good prospects for lung cancer treatments. In particular, compared to inorganic Se (Inorg-Se) and organic Se (Org-Se), Se nanomedicine (Se nanoparticles; SeNPs) shows much higher bioavailability and antioxidant activity and lower toxicity. SeNPs can also be used as a drug delivery carrier to better regulate protein and DNA biosynthesis and protein kinase C activity, thus playing a role in inhibiting cancer cell proliferation. SeNPs can also effectively activate antigen-presenting cells to stimulate cell immunity, exert regulatory effects on innate and regulatory immunity, and enhance lung cancer immunotherapy. This review summarizes the application of Se-based species and materials in lung cancer diagnosis, including fluorescence, MR, CT, photoacoustic imaging and other diagnostic methods, as well as treatments, including direct killing, radiosensitization, chemotherapeutic sensitization, photothermodynamics, and enhanced immunotherapy. In addition, the application prospects and challenges of Se-based drugs in lung cancer are examined, as well as their forecasted future clinical applications and sustainable development.

Selenium Silk Nanostructured Films with Antifungal and Antibacterial Activity

The rapid emergence of drug-resistant bacteria and fungi poses a threat for healthcare worldwide. The development of novel effective small molecule therapeutic strategies in this space has remained challenging. Therefore, one orthogonal approach is to explore biomaterials with physical modes of action that have the potential to generate antimicrobial activity and, in some cases, even prevent antimicrobial resistance. Here, to this effect, we describe an approach for forming silk-based films that contain embedded selenium nanoparticles. We show that these materials exhibit both antibacterial and antifungal properties while crucially also remaining highly biocompatible and noncytotoxic toward mammalian cells. By incorporating the nanoparticles into silk films, the protein scaffold acts in a 2-fold manner; it protects the mammalian cells from the cytotoxic effects of the bare nanoparticles, while also providing a template for bacterial and fungal eradication. A range of hybrid inorganic/organic films were produced and an optimum concentration was found, which allowed for both high bacterial and fungal death while also exhibiting low mammalian cell cytotoxicity. Such films can thus pave the way for next-generation antimicrobial materials for applications such as wound healing and as agents against topical infections, with the added benefit that bacteria and fungi are unlikely to develop antimicrobial resistance to these hybrid materials.

Antifungal Properties of Biogenic Selenium Nanoparticles Functionalized with Nystatin for the Inhibition of Candida albicans Biofilm Formation

In the present study, biogenic selenium nanoparticles (SeNPs) have been prepared using Paenibacillus terreus and functionalized with nystatin (SeNP@PVP_Nystatin nanoconjugates) for inhibiting growth, morphogenesis, and a biofilm in Candida albicans. Ultraviolet-visible spectroscopy analysis has shown a characteristic absorption at 289, 303, and 318 nm, and X-ray diffraction analysis has shown characteristic peaks at different 2θ values for SeNPs. Electron microscopy analysis has shown that biogenic SeNPs are spherical in shape with a size in the range of 220-240 nm. Fourier transform infrared spectroscopy has confirmed the functionalization of nystatin on SeNPs (formation of SeNP@PVP_Nystatin nanoconjugates), and the zeta potential has confirmed the negative charge on the nanoconjugates. Biogenic SeNPs are inactive; however, nanoconjugates have shown antifungal activities on C. albicans (inhibited growth, morphogenesis, and a biofilm). The molecular mechanism for the action of nanoconjugates via a real-time polymerase chain reaction has shown that genes involved in the RAS/cAMP/PKA signaling pathway play an important role in antifungal activity. In cytotoxic studies, nanoconjugates have inhibited only 12% growth of the human embryonic kidney cell line 293 cells, indicating that the nanocomposites are not cytotoxic. Thus, the biogenic SeNPs produced by P. terreus can be used as innovative and effective drug carriers to increase the antifungal activity of nystatin.

Biogenic Selenium Nanoparticles in Biomedical Sciences: Properties, Current Trends, Novel Opportunities and Emerging Challenges in Theranostic Nanomedicine

Selenium is an important dietary supplement and an essential trace element incorporated into selenoproteins with growth-modulating properties and cytotoxic mechanisms of action. However, different compounds of selenium usually possess a narrow nutritional or therapeutic window with a low degree of absorption and delicate safety margins, depending on the dose and the chemical form in which they are provided to the organism. Hence, selenium nanoparticles (SeNPs) are emerging as a novel therapeutic and diagnostic platform with decreased toxicity and the capacity to enhance the biological properties of Se-based compounds. Consistent with the exciting possibilities offered by nanotechnology in the diagnosis, treatment, and prevention of diseases, SeNPs are useful tools in current biomedical research with exceptional benefits as potential therapeutics, with enhanced bioavailability, improved targeting, and effectiveness against oxidative stress and inflammation-mediated disorders. In view of the need for developing eco-friendly, inexpensive, simple, and high-throughput biomedical agents that can also ally with theranostic purposes and exhibit negligible side effects, biogenic SeNPs are receiving special attention. The present manuscript aims to be a reference in its kind by providing the readership with a thorough and comprehensive review that emphasizes the current, yet expanding, possibilities offered by biogenic SeNPs in the biomedical field and the promise they hold among selenium-derived products to, eventually, elicit future developments. First, the present review recalls the physiological importance of selenium as an oligo-element and introduces the unique biological, physicochemical, optoelectronic, and catalytic properties of Se nanomaterials. Then, it addresses the significance of nanosizing on pharmacological activity (pharmacokinetics and pharmacodynamics) and cellular interactions of SeNPs. Importantly, it discusses in detail the role of biosynthesized SeNPs as innovative theranostic agents for personalized nanomedicine-based therapies. Finally, this review explores the role of biogenic SeNPs in the ongoing context of the SARS-CoV-2 pandemic and presents key prospects in translational nanomedicine.

Allotropy of selenium nanoparticles: Colourful transition, synthesis, and biotechnological applications

Elemental selenium (Se⁰ ) nanomaterials undergo allotropic transition from thermodynamically-unstable to more stable phases. This process is significantly different when Se⁰ nanoparticles (NPs) are produced via physico-chemical and biological pathways. While the allotropic transition of physico-chemically synthesized Se⁰ is fast (minutes to hours), the biogenic Se⁰ takes months to complete. The biopolymer layer covering biogenic Se⁰ NPs might be the main factor controlling this retardation, but this still remains an open question. Phylogenetically-diverse bacteria reduce selenium oxyanions to red amorphous Se⁰ allotrope, which has low market value. Then, red Se⁰ undergoes allotropic transition to trigonal (metallic grey) allotrope, the end product having important industrial applications (e.g. semiconductors, alloys). Is it not yet clear whether biogenic Se⁰ presents any biological function, or it is mainly a detoxification and respiratory by-product. The better understanding of this transition would benefit the recovery of Se⁰ NPs from secondary resources and its targeted utilization with respect to each allotropic stage. This review article presents and critically discusses the main physico-chemical methods and biosynthetic pathways of Se⁰ (bio)mineralization. In addition, the article proposes a conceptual model for the resource recovery potential of trigonal selenium nanomaterials in the context of circular economy.

Mesenchymal Stem Cells and Selenium Nanoparticles Synergize with Low Dose of Gamma Radiation to Suppress Mammary Gland Carcinogenesis via Regulation of Tumor Microenvironment

Breast cancer is one of the most prevalent and deadliest cancers among women in the world because of its aggressive behavior and inadequate response to conventional therapies. Mesenchymal stem cells (MSCs) combined with green nanomaterials could be an efficient tool in cell cancer therapy. This study examined the curative effects of bone marrow-derived mesenchymal stem cells (BM-MSCs) with selenium nanoparticles (SeNPs) coated with fermented soymilk and a low dose of gamma radiation (LDR) in DMBA-induced mammary gland carcinoma in female rats. DMBA-induced mammary gland carcinoma as marked by an elevation of mRNA level of cancer promoter genes (Serpin and MIF, LOX-1, and COL1A1) and serum level of VEGF, TNF-α, TGF-β, CA15-3, and caspase-3 with the reduction in mRNA level of suppressor gene (FST and ADRP). These deleterious effects were hampered after treatment with BM-MSCs (1 × 10⁶ cells/rat) once and daily administration of SeNPs (20 mg/kg body weight) and exposure once to (0.25 Gy) LDR. Finally, MSCs, SeNPs, and LDR notably modulated the expression of multiple tumor promoters and suppressor genes playing a role in breast cancer induction and suppression.

Advanced nanomaterials for modulating Alzheimer's related amyloid aggregation

Alzheimer's disease (AD) is a common neurodegenerative disease that brings about enormous economic pressure to families and society. Inhibiting abnormal aggregation of Aβ and accelerating the dissociation of aggregates is treated as an effective method to prevent and treat AD. Recently, nanomaterials have been applied in AD treatment due to their excellent physicochemical properties and drug activity. As a drug delivery platform or inhibitor, various excellent nanomaterials have exhibited potential in inhibiting Aβ fibrillation, disaggregating, and clearing mature amyloid plaques by enhancing the performance of drugs. This review comprehensively summarizes the advantages and disadvantages of nanomaterials in modulating amyloid aggregation and AD treatment. The design of various functional nanomaterials is discussed, and the strategies for improved properties toward AD treatment are analyzed. Finally, the challenges faced by nanomaterials with different dimensions in AD-related amyloid aggregate modulation are expounded, and the prospects of nanomaterials are proposed.

Microbes-mediated synthesis strategies of metal nanoparticles and their potential role in cancer therapeutics

Past few years have seen a paradigm shift towards ecofriendly, green and biological fabrication of metal nanoparticles (MNPs) for diverse nanomedicinal applications especially in cancer nanotheranostics. Besides, the well-known green synthesis methods of plant materials, the potential of the microbial world (bacteria, fungi, alga, etc.) in biofabrication is equally realized. Biomolecules and enzymes in the microbial cells are capable of catalyzing the biosynthesis process. These microbial derived inorganic nanoparticles have been frequently evaluated as potential agents in cancer therapies revealing exciting results. Through, cellular and molecular pathways, these microbial derived nanoparticles are capable of killing the cancer cells. Considering the recent developments in the anticancer applications of microbial derived inorganic MNPs, a dire need was felt to bring the available information to a single document. This manuscript reviews not only the mechanistic aspects of the microbial derived MNPs but also include the diverse mechanisms that governs their anticancer potential. Besides, an updated literature review is presented that includes studies of 2019-onwards.

Mycosynthesis of highly fluorescent selenium nanoparticles from Fusarium oxysporum, their antifungal activity against black fungus Aspergillus niger, and in-vivo biodistribution studies

In the past few years, photo-luminescent inorganic materials have been studied extensively as fluorescent sensors, and diagnostic and bioimaging tools. The assessment of photoluminescence (PL) properties of selenium nanoparticles (Se NPs), especially mycosynthesized Se NPs, is still in its infancy. Herein, we have biosynthesized highly dispersed fluorescent Se NPs (42 nm) using endophytic fungus Fusarium oxysporum, and fully characterized them using sophisticated instruments like TEM, XRD, UV–Vis spectrophotometer, FTIR, and PL spectrometer. To determine the therapeutic efficacy and side effect profiles, these crystalline Se NPs were radiolabeled with technetium-99m (^99mTc) and their biodistribution and renal clearance times were investigated in the normal Wister rat. The results showed that these Se NPs may be useful for targeting the lungs and liver dysfunction as significant accumulation of these NPs was observed in the liver (approx. 19.47 ± 4%) and lungs (at 6 ± 1%) after 10 min of post-injection. Quick circulation and the presence of Se NPs in kidney (3.8 ± 2%) also suggested the easy excretion of these NPs from the body through urinary tract. Furthermore, the antioxidant activity of Se NPs (IC₅₀, 159.5 μg/mL) has been investigated using DPPH free radical scavenging assay with scavenging efficacy of 80.4% where ascorbic acid (IC₅₀, 5.6 μg/mL) was used as a positive control. Additionally, the microscopic study of the inhibition zone encircled around Se NPs confirmed their strong antifungal and antisporulant activity against the black fungus Aspergillus niger.

Antimicrobial, Antiviral, and In-Vitro Cytotoxicity and Mosquitocidal Activities of Portulaca oleracea-Based Green Synthesis of Selenium Nanoparticles

The aqueous extract of Portulaca oleracea was used as a biocatalyst for the reduction of Na₂SeO₃ to form Se-NPs that appeared red in color and showed maximum surface plasmon resonance at a wavelength of 266 nm, indicating the successful Phyto-fabrication of Se-NPs. A FT-IR chart clarified the role of plant metabolites such as proteins, carbohydrates, and amino acids in capping and stabilizing Se-NPs. TEM, SAED, and XRD analyses indicated the formation of spherical, well-arranged, and crystalline Se-NPs with sizes in the range of 2-22 nm. SEM-EDX mapping showed the maximum peaks of Se at 1.4, 11.3, and 12.4 KeV, with weight and atomic percentages of 36.49 and 30.39%, respectively. A zeta potential of -43.8 mV also indicated the high stability of the synthesized Se-NPs. The Phyto-synthesized Se-NPs showed varied biological activities in a dose-dependent manner, including promising activity against pathogenic bacteria and Candida species with varied MIC values in the range of 12.5-50 µg·mL^-1. Moreover, the Se-NPs showed antiviral activity toward HAV and Cox-B4, with percentages of 70.26 and 62.58%, respectively. Interestingly, Se-NPs showed a target orientation to cancer cell lines (HepG2) with low IC₅₀ concentration at 70.79 ± 2.2 µg·mL^-1 compared to normal cell lines (WI-38) with IC₅₀ at165.5 ± 5.4 µg·mL^-1. Moreover, the as-formed Se-NPs showed high activity against various instar larvae I, II, III, and IV of Culex pipiens, with the highest mortality percentages of 89 ± 3.1, 73 ± 1.2, 68 ± 1.4, and 59 ± 1.0%, respectively, at 50 mg L^-1. Thus, P. oleracea-based Se-NPs would be strong potential antimicrobial, anti-viral, anti-cancer, and anti-insect agents in the pharmaceutical and biomedical industries.

Unveiling Antimicrobial and Insecticidal Activities of Biosynthesized Selenium Nanoparticles Using Prickly Pear Peel Waste

In the current study, prickly pear peel waste (PPPW) extract was used for the biosynthesis of selenium nanoparticles through a green and eco-friendly method for the first time. The biosynthesized SeNPs were characterized using UV-Vis, XRD, FTIR, TEM, SEM, EDX, and mapping. Characterization results revealed that biosynthesized SeNPs were spherical, polydisperse, highly crystalline, and had sizes in the range of 10–87.4 nm. Antibacterial, antifungal, and insecticidal activities of biosynthesized SeNPs were evaluated. Results revealed that SeNPs exhibited promising antibacterial against Gram negative (E. coli and P. aeruginosa) and Gram positive (B. subtilis and S. aureus) bacteria where MICs were 125, 125, 62.5, and 15.62 µg/mL, respectively. Moreover, SeNPs showed potential antifungal activity toward Candida albicans and Cryptococcus neoformans where MICs were 3.9 and 7.81 µg/mL, respectively. Furthermore, tested crud extract and SeNPs severely induced larvicidal activity for tested mosquitoes with LC50 and LC90 of 219.841, 950.087 mg/L and 75.411, 208.289 mg/L, respectively. The fecundity and hatchability of C. pipiens mosquito were significantly decreased as applied concentrations increased either for the crude or the fabricated SeNPs extracts. In conclusion, the biosynthesized SeNPs using prickly pear peel waste have antibacterial, antifungal, and insecticidal activities, which can be used in biomedical and environmental applications.

Light enhanced the antimicrobial, anticancer, and catalytic activities of selenium nanoparticles fabricated by endophytic fungal strain, Penicillium crustosum EP-1

Selenium nanoparticles (Se-NPs) has recently received great attention over owing to their superior optical properties and wide biological and biomedical applications. Herein, crystallographic and dispersed spherical Se-NPs were green synthesized using endophytic fungal strain, Penicillium crustosum EP-1. The antimicrobial, anticancer, and catalytic activities of biosynthesized Se-NPs were investigated under dark and light (using Halogen tungsten lamp, 100 Watt, λ > 420 nm, and light intensity of 2.87 W m⁻²) conditions. The effect of Se-NPs was dose dependent and higher activities against Gram-positive and Gram-negative bacteria as well different Candida spp. were attained in the presence of light than obtained under dark conditions. Moreover, the viabilities of two cancer cells (T47D and HepG2) were highly decreased from 95.8 ± 2.9% and 93.4 ± 3.2% in dark than those of 84.8 ± 2.9% and 46.4 ± 3.3% under light-irradiation conditions, respectively. Significant decreases in IC₅₀ values of Se-NPs against T47D and HepG2 were obtained at 109.1 ± 3.8 and 70.4 ± 2.5 µg mL⁻¹, respectively in dark conditions than 19.7 ± 7.2 and 4.8 ± 4.2 µg mL⁻¹, respectively after exposure to light-irradiation. The photoluminescence activity of Se-NPs revealed methylene blue degradation efficiency of 89.1 ± 2.1% after 210 min under UV-irradiation compared to 59.7 ± 0.2% and 68.1 ± 1.03% in dark and light conditions, respectively. Moreover, superior stability and efficient MB degradation efficiency were successfully achieved for at least five cycles.

Green Biosynthesis of Selenium Nanoparticles Using Orange Peel Waste: Characterization, Antibacterial and Antibiofilm Activities against Multidrug-Resistant Bacteria

There is an increase of pathogenic multidrug-resistant bacteria globally due to the misuse of antibiotics. Recently, more scientists used metal nanoparticles to counteract antibacterial resistance. In this study, orange peel waste (OPW) was used for selenium nanoparticles’ (Se-NPs) biosynthesis through the green and ecofriendly method, and their applications as antibacterial and antibiofilm agents. Green biosynthesized Se-NPs were characterized using FTIR, XRD, SEM, EDAX, and TEM. Characterization results revealed that biosynthesized Se-NPs were highly crystalline, spherical, and polydisperse, and had sizes in the range of 16–95 nm. The biosynthesized Se-NPs were evaluated as antibacterial and antibiofilm activities against multidrug-resistant bacteria. Results illustrated that Se-NPs exhibited potential antibacterial activity against Gram-positive bacteria (S. aureus ATCC 29213 and biofilm-producing clinical isolates of S. aureus) and Gram-negative bacteria (Pseudomonas aeruginosa PAO1, MDR, biofilm, and quorum-sensing and producing clinical isolates of MDR P. aeruginosa, MDR E. coli, and K. pneumonia). Moreover, results illustrated that S. aureus ATCC 29213 was the most sensitive bacteria to Se-NPs at 1000 µg/mL, where the inhibition zone was 35 mm and MIC was 25 µg/mL. Furthermore, Se-NPs at 0.25 and 0.5 MIC decreased the biofilm significantly. The largest inhibition of biofilm was noticed in MDR K. pneumonia, which was 62% and 92% at 0.25 and 0.5 MIC, respectively. In conclusion, Se-NPs were successfully biosynthesized using OPW through the green method and had promising antibacterial and antibiofilm activity against multidrug-resistant bacteria, which can be used later in fighting resistant bacteria.

A New Strategy for Microbial Taxonomic Identification through Micro-Biosynthetic Gold Nanoparticles and Machine Learning

Microorganisms can serve as biological factories for the synthesis of inorganic nanomaterials that can become useful as nanocatalysts, energy-harvesting-storage components, antibacterial agents, and biomedical materials. Herein, the development of biosynthesis of inorganic nanomaterials into a simple, stable, and accurate strategy for distinguishing microorganisms from multiple classification levels (i.e., kingdom, order, genus, and species) without gene amplification, biochemical testing, or target recognition is reported. Gold nanoparticles (AuNPs) biosynthesized by different microorganisms differ in color of the solution, and their features can be characterized, including the particle size, the surface plasmon resonance (SPR) spectrum, and the surface potential. The inter-relation between the features of micro-biosynthetic AuNPs and the classification of microorganisms are exploited at different levels through machine learning to establish a taxonomic model. This model agrees well with traditional classification methods that offers a new strategy for microbial taxonomic identification. The underlying mechanism of this strategy is related to the biomolecules produced by different microorganisms including glucose, glutathione, and nicotinamide adenine dinucleotide phosphate-dependent reductase that regulate the features of micro-biosynthetic AuNPs. This work broadens the application of biosynthesis of inorganic materials through micro-biosynthetic AuNPs and machine learning, which holds great promise as a tool for biomedical research.

Enterococcus spp. Cell-Free Extract: An Abiotic Route for Synthesis of Selenium Nanoparticles (SeNPs), Their Characterisation and Inhibition of Escherichia coli

Selenite (SeO₃²⁻), the most toxic and most reactive selenium (Se) oxyanion, can be reduced to elemental selenium (Se⁰) nanoparticles by a variety of bacteria, including Enterococcus spp. Previously, the orthodox view held that the reduction of SeO₃²⁻ to Se⁰ by a wide range of bacteria was solely accomplished by biological processes; however, recent studies have shown that various bacterial strains secrete metal-reducing metabolites, thereby indirectly catalysing the reduction of these metal species. In the current study, selenium nanoparticles were synthesised from the abiotic reduction of selenite with the use of Enterococcus spp. cell-free extract. Once separated from the cell-free extract, the particles were analysed using Fourier-transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), Transmission electron microscopy (TEM) and a Zetasizer. The results revealed that the SeNPs were spherical in shape, containing both amorphous and crystalline properties, and the sizes with the highest frequency ranged close to 200 nm. Additionally, the obtained nanoparticles exhibited antimicrobial properties by directly inhibiting the viability of an E. coli bacterial strain. The results demonstrate not only the potential of abiotic production of SeNPs, but also the potential for these particles as microbial inhibitors in medical or similar fields.

Sensitization of Epidermal Growth Factor Receptor (EGFR) Inhibitors Induced by Radiotherapy Combined with Programmed Death Ligand-1 (PD-L1) Inhibitors

To explore the effect of radiotherapy combined with programmed death ligand-1 (PD-L1) inhibitors on the sensitization of epidermal growth factor receptor (EGFR) inhibitors, 76 patients with nonsmall cell lung cancer (NSCLC) were rolled into group A (lung adenocarcinoma, 55 cases) and group B (lung squamous carcinoma, 21 cases). Another 63 healthy volunteers were set as controls (group C). Patients in group A were rolled into mutation group (15 cases) and wild group (22 cases) regarding the presence of EGFR mutations. The sPD-L1 protein in serum samples was determined via enzyme-linked immunosorbent assay (ELISA). Expressions of PD-L1, EGFR, and immune interferon (IFN-γ) in lung cancer cell lines (LCCL) mutant PC9 and HCC827, and wild-type A549 and H1299 were analyzed. After separation of T lymphocytes, four LCCLs and T lymphocytes were co-cultured to detect the proliferation and apoptosis of T lymphocytes. The results showed that PD-L1 level in EGFR-sensitive mutant LCCLs PC9 and HCC827 after X-ray irradiation was obviously inferior to controls (P < 0.05). The proliferation of T cells in mutant LCCLs PC9 and HCC827 was substantially superior to co-culture system (co-CS) (P < 0.05). After the PC9 co-CS was treated with X-rays, PD-L1 inhibitors, and X-rays combined with PD-L1 inhibitors, the secretion of IFN-γ was markedly increased versus controls (P < 0.05). In short, radiotherapy combined with PD-L1 inhibitors can enhance the proliferation of T cells and inhibit their apoptosis, and greatly increase the secretion of IFN-γ by T cells.

Green-synthetized selenium nanoparticles using berberine as a promising anticancer agent

OBJECTIVE

The chemo-preventative and therapeutic properties of selenium nanoparticles (SeNPs) have been documented over recent decades and suggest the potential uses of SeNPs in medicine. Biogenic SeNPs have higher biocompatibility and stability than chemically synthesized nanoparticles, which enhances their medical applications, especially in the field of cancer therapy. This study evaluated the potential of green-synthetized SeNPs by using berberine (Ber) as an antitumor agent and elucidated the mechanism by which these molecules combat Ehrlich solid tumors (ESTs).

METHODS

SeNPs containing Ber (SeNPs-Ber) were synthesized using Ber and Na₂SeO₃ and characterized with Fourier transform infrared spectroscopy. Sixty male Swiss albino mice were then acclimatized for one week, injected with Ehrlich ascites tumor cells, and divided into four groups: EST, EST + cisplatin (5 mg/kg), EST + Ber (20 mg/kg), and EST + SeNPs-Ber (0.5 mg/kg). At the end of a 16-day observation period, 12 mice from each group were euthanized to analyze differences in the body weight, tumor size, gene expression, and oxidative stress markers in the four groups. Three mice from each group were kept alive to compare the survival rates.

RESULTS

Treatment with SeNPs-Ber significantly improved the survival rate and decreased the body weight and tumor size, compared to the EST group. SeNPs-Ber reduced oxidative stress in tumor tissue, as indicated by a decrease in the lipid peroxidation and nitric oxide levels and an increase in the glutathione levels. Moreover, SeNPs-Ber activated an apoptotic cascade in the tumor cells by downregulating the B-cell lymphoma 2 (Bcl-2) expression rate and upregulating the Bcl-2-associated X protein and caspase-3 expression rates. SeNPs-Ber also considerably improved the histopathological alterations in the developed tumor tissue, compared to the EST group.

CONCLUSION

Our study provides a new insight into the potential role of green-synthesized SeNPs by using Ber as a promising anticancer agent, these molecules could be used alone or as supplementary medication during chemotherapy.

Selenium donor restricts the intracellular growth of Mycobacterium tuberculosis through the induction of c-Jun-mediated both canonical autophagy and LC3-associated phagocytosis of alveolar macrophages

The relationship between selenium and Mycobacterium tuberculosis (MTB) infection has been reported previously; however, the specific mechanism is still not clear. In this study, selenium levels decreased in the serum of patients with pulmonary tuberculosis (PTB) compared with the healthy controls; they were associated with the treatment outcome of such patients. The qRT-PCR assay revealed that selenium might function through proinflammatory and autophagy pathways. The treatment with methylseleninic acid (MSeA), a selenium donor, blocked the M1 polarization of MTB-infected macrophages through the induction of both canonical autophagy and LC3-associated phagocytosis (LAP). c-Jun is vital in mediating the MSeA-triggered canonical autophagy and LAP process, thus displaying a restricting function against intracellular MTB. An in vivo study confirmed that the activity of MSeA was shown through enhancing macrophage autophagy related pathway. The results showed that selenium had a restricting function against intracellular MTB by regulating autophagy in macrophages. The findings might provide a novel direction for PTB therapy in the future.

Anticancer Activity of Selenium Nanoparticles In Vitro Studies

Health systems worldwide consider cancer a disease that causes the highest number of deaths per year. The low efficacy of current cancer therapies has led other areas of science to search for new alternatives, including nanomaterial sciences. Selenium nanoparticles have anticancer activity, as revealed by in vitro tests performed on prostate, breast, cervical, lung, colorectal, and liver cancer cell lines. Studies attribute anticancer activity to the anti-metastatic effect due to the inhibition of migration and invasion processes. The antiproliferative effect is the low expression of molecules such as cyclin D1, cyclin E, and CDK2. In addition to the activation of cell apoptosis by caspase-dependent mechanisms, there is a low expression of anti-apoptotic proteins such as Bcl-2 and a high expression of the apoptotic proteins like Bax and Bad. Other studies attribute anticancer activity to the activation of cell necroptosis, where molecules such as TNF and IRF1 participate. The pharmacological potential of selenium nanoparticles depends primarily on the administered dose, particle size, and chemical composition. Furthermore, several studies have shown that the administration of these nanoparticles is safe due to their low toxicity in non-cancerous cells. In this review, the most relevant antecedents on the anticancer potential of selenium nanoparticles in prostate, breast, cervical, lung, liver, and colorectal cancer cell lines are discussed.

Selenium nanoparticles inhibit tumor metastasis in prostate cancer through upregulated miR-155-5p-related pathway

Prostate cancer are the most common, malignant and lethal tumors in men, and the complexity of prostate cancer (CaP) is also due to the diverse metastasis profile. Selenium nanoparticles (SeNPs) have been reported to have potent antitumor activity, but whether it impacted the tumor metastasis is not fully clear. Here, we confirmed that SeNPs could inhibit the CaP cell migrations and invasions. Combined with our previous findings, we identified a series of microRNAs that could be upregulated significantly under SeNP treatment, among which miR-155-5p acts as a key component in mediating the SeNP-inhibited migration and invasion of CaP cells, through directly targeting IκB kinase ɛ and Sma- and Mad-related protein 2. The cell-based results were proved in xenograft mice modeling. These results have evidently signified the antitumor potential of SeNPs in the treatment of prostate cancer.

Selenium nanoparticles reduce glucose metabolism and promote apoptosis of glioma cells through reactive oxygen species-dependent manner

Gliomas are the most common, malignant, and lethal tumors in adults. Furthermore, gliomas are highly resistant to current chemotherapeutic drugs. Thus, new effective anticancer drugs for glioma are urgently needed. Selenium nanoparticles have been reported to have potent anti-tumor activity, although the specific mechanism is not fully understood. This study aimed to test the anti-tumor effect of selenium nanoparticles and its mechanism. We used selenium nanoparticles to treat commercial glioma cell lines, and patient-derived glioma cells, and then used the MTT assay to determine selenium nanoparticles effect against these. Apoptotic cell death was determined by annexin V-Fluos staining kit. Glucose uptake, lactate, and adenosine triphosphate production, together with hexokinase 2 and pyruvate kinase activities were measured to determine the glucose metabolism level. Reactive oxygen species production was tested using 2',7'-dichlorodihydrofluorescein diacetate. Our results showed that selenium nanoparticles had a potent cytotoxic effect in glioma cells, regardless of whether they were drug-resistant or not, whereas it showed less toxic effect in normal healthy cells. Further tests showed that selenium nanoparticles treatment leads to apoptotic cell death enhancement and glucose metabolism reduction, and this process was in a reactive oxygen species pathway-dependent manner. These results may provide a novel direction for glioma therapy in the future.

Potentialities of selenium nanoparticles in biomedical science

Selenium nanoparticles (SeNPs) have revolutionized biomedical domain and are still developing rapidly. Hence, this perspective elaborates SeNPs properties, synthesis, and biomedical applications, together with their potential for management of SARS-CoV-2.

Biosynthesis of inorganic nanomaterials using microbial cells and bacteriophages

Inorganic nanomaterials are widely used in chemical, electronics, photonics, energy and medical industries. Preparing a nanomaterial (NM) typically requires physical and/or chemical methods that involve harsh and environmentally hazardous conditions. Recently, wild-type and genetically engineered microorganisms have been harnessed for the biosynthesis of inorganic NMs under mild and environmentally friendly conditions. Microorganisms such as microalgae, fungi and bacteria, as well as bacteriophages, can be used as biofactories to produce single-element and multi-element inorganic NMs. This Review describes the emerging area of inorganic NM biosynthesis, emphasizing the mechanisms of inorganic-ion reduction and detoxification, while also highlighting the proteins and peptides involved. We show how analysing a Pourbaix diagram can help us devise strategies for the predictive biosynthesis of NMs with high producibility and crystallinity and also describe how to control the size and morphology of the product. Here, we survey biosynthetic inorganic NMs of 55 elements and their applications in catalysis, energy harvesting and storage, electronics, antimicrobials and biomedical therapy. Furthermore, a step-by-step flow chart is presented to aid the design and biosynthesis of inorganic NMs employing microbial cells. Future research in this area will add to the diversity of available inorganic NMs but should also address scalability and purity.

Selenium donors inhibits osteoclastogenesis through inhibiting IL-6 and plays a pivotal role in bone metastasis from breast cancer

Bone metastases are a frequent complication of breast cancer, and there has been little progress in the treatment of breast cancer patients with bone metastases. The cytotoxicity of selenium donors, including organic selenium and selenium nanoparticles (SeNPs), to cancer cells has been reported previously, but their relationship with bone metastases progression is not fully clear yet. In this study, multicenter clinical exploration was conducted to obtain dietary selenium intakes of breast cancer patients with or without bone metastasis, to study the relationship between selenium and breast cancer prognosis and bone metastasis. We found that dietary selenium intakes were significantly lower in breast cancer patients with bone metastasis, comparing with the non-bone metastasis cases. Selenium lower group of bone metastasis breast cancer patients had worse prognosis, whereas the daily selenium intakes could not predict the prognosis of breast cancer patients without bone metastasis. Subsequently, we study the regulatory role of selenium donors on bone metastasis at the cellular level, by challenging the cells with SeNPs. SeNPs showed potent cytotoxicity in breast cancer cells, no matter whether they were primary or bone-metastatic. SeNPs treated cancer cell inhibited the survival and differentiation of osteoclast progenitor cells. At the molecular level, we demonstrated that IL-6 partially mediated osteoclastogenesis suppression by SeNPs. These results provide a new way for biomarkers or drug development to treat and even prevent bone metastases of breast cancer by using selenium donors.

Surface-functionalised hybrid nanoparticles for targeted treatment of cancer

Cancer is a leading cause of death worldwide. Despite the great advancement in understanding the pharmacology and biology of cancer, it still signifies one of the most serious human-health related problems. The current treatments for cancer may include surgery, radiotherapy, and chemotherapy, but these procedures have several limitations. Current studies have shown that nanoparticles (NPs) can be used as a novel strategy for cancer treatment. Developing nanosystems that allow lower doses of therapeutic agents, as well as their selective release in tumour cells, may resolve the challenges of targeted cancer therapy. In this review, the authors discuss the role of the size, shape, and surface modifications of NPs in cancer treatment. They also address the challenges associated with cancer therapies based on NPs. The overall purpose of this review is to summarise the recent developments in designing different hybrid NPs with promising therapeutic properties for different types of cancer.

Selenium nanoparticles (SeNPs) have potent antitumor activity against prostate cancer cells through the upregulation of miR-16

Objectives

This research aimed to examine the antitumor mechanisms of selenium nanoparticles (SeNPs) specifically against prostate cancers.

Methods

The antitumor activities of SeNPs against cancer cells were determined via MTT assay. The cell cycle was determined by detecting the DNA content, and apoptosis was determined via annexin V-Fluos staining kit. The microRNA expressions in cancer cells were analyzed via microarray and qRT-PCR. The potential targets of miR-16 were identified via luciferase analysis and mRNA expression determination. miR-16 functions in cancer cells were explored via the transient transfection of miR-16 mimic or inhibitor.

Results

SeNPs were most potent in prostate cancer cells, regardless of whether or not they were androgen-dependent. Furthermore, SeNP stimulation can induce cell cycle arrest and the apoptosis enhancement of prostate cancer cells. Microarray and molecular mechanism studies demonstrated that miR-16 could directly target cyclin D1 and BCL-2 to mediate SeNP apoptosis enhancement. Results show that the serum selenium levels positively correlate with miR-16 expressions, and they correlate with the overall and disease-free survival rates.

Conclusion

These results signify the cytotoxic potential of SeNPs in prostate cancer treatment.

Cytotoxic effect of silica nanoparticles against hepatocellular carcinoma cells through necroptosis induction

Hepatocellular carcinoma (HCC) is a common cancer that affects people worldwide with high morbidity and mortality, and its resistance to current chemotherapeutic drugs is a serious concern. Cytotoxicity of silica nanoparticles (Nano-SiO₂) towards cancer cells has been reported previously, but the specific mechanism is not fully clear. In this study, Nano-SiO₂ showed a remarkable cytotoxic effect against HCC cells, regardless of whether the cells were drug resistant or not. Further study showed that Nano-SiO₂ treatment leads to cell cycle arrest, apoptosis enhancement and necroptosis induction in the HCC cells. RNA-seq data, together with bioinformatics analysis, revealed that a series of genes involved in cancer cell death could be regulated by Nano-SiO₂, among which ZBP-1 was up-regulated the most by Nano-SiO₂ treatment. The siRNA based experiments demonstrated that ZBP-1 might play a key role in mediating Nano-SiO₂ cytotoxic functions against HCC cells. These results have evidently signified the anti-tumor potential of Nano-SiO₂ in the treatment of HCC.

Microwave-Assisted Green Synthesis and Antioxidant Activity of Selenium Nanoparticles Using Theobroma Cacao L. Bean Shell Extract

Selenium nanoparticles (SeNPs) are successfully synthesized through microwave heating by using Theobroma cacao L. bean shell extract as a stabilizing and capping agent. Response surface methodology is used to obtain optimal synthesis conditions. The effect of microwave power, irradiation time and amount of Na2SeO3 are evaluated on crystalline size by X-Ray Diffraction (XRD) and Z-potential by Dynamic Light Scattering (DLS) using a central composite design (CCD). Optimal synthesis conditions are determined as 15.6 min, 788.6 W and 0.14 g of sodium selenite using 50 mL of Theobroma cacao L. bean shell extract. The successful biosynthesis of SeNPs is confirmed by UV-visible and Fourier Transformed Infrared (FTIR) spectroscopic analyses. The XRD pattern and Raman spectra show the presence of trigonal and amorphous synthesized SeNPs. Spherical SeNPs are observed by Transmission Electron Microscopy (TEM) with a particle size of 1-3 nm in diameter, at least one order of magnitude lower than those previously reported. The obtained SeNPs can be stable up to 55 days at 4 °C. Additionally, the SeNPs show an excellent antioxidant performance by the 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) and ferric reducing antioxidant power (FRAP) methods, with potential application in different sectors, such as food, medical and pharmaceutical.