Gold nanoparticles enhance TRAIL sensitivity through Drp1-mediated apoptotic and autophagic mitochondrial fission in NSCLC cells

TRIAL-based combination therapies in cancers

Tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) shows promising therapeutic potential in cancer treatment as it is able to trigger extrinsic apoptotic pathways by binding to the cognate death receptor, causing broad-spectrum apoptosis in cancer cells with negligible toxicity to normal cells. However, the majority of cancers display resistance to TRAIL, limiting its clinical utility. Overcoming resistance to TRAIL therapies remains a challenge in the development of effective anti-cancer strategies. To address the limitations of TRAIL therapy, a viable alternative approach involves combining TRAIL with more potent drugs compared to monotherapy. This combination strategy aims to induce synergistic effects or sensitize drug-resistant cancer cells. This review provides an overview of relevant modalities of TRAIL combination therapy, highlighting different drug classes. The findings demonstrate that combining TRAIL with other agents can effectively counteract resistance observed with TRAIL therapies in cancer. These findings lay a foundation for future advancements in TRAIL-based therapies for treating various cancers.

Nanomaterials-induced programmed cell death: Focus on mitochondria

Nanomaterials are widely utilized in several domains, such as everyday life, societal manufacturing, and biomedical applications, which expand the potential for nanomaterials to penetrate biological barriers and interact with cells. Multiple studies have concentrated on the particular or improper utilization of nanomaterials, resulting in cellular death. The primary mode of cell death caused by nanotoxicity is programmable cell death, which includes apoptosis, ferroptosis, necroptosis, and pyroptosis. Based on our prior publications and latest research, mitochondria have a vital function in facilitating programmed cell death caused by nanomaterials, as well as initiating or transmitting death signal pathways associated with it. Therefore, this review takes mitochondria as the focal point to investigate the internal molecular mechanism of nanomaterial-induced programmed cell death, with the aim of identifying potential targets for prevention and treatment in related studies.

Mitophagy and its regulatory mechanisms in the biological effects of nanomaterials

Mitophagy is a selective cellular process critical for the removal of damaged mitochondria. It is essential in regulating mitochondrial number, ensuring mitochondrial functionality, and maintaining cellular equilibrium, ultimately influencing cell destiny. Numerous pathologies, such as neurodegenerative diseases, cardiovascular disorders, cancers, and various other conditions, are associated with mitochondrial dysfunctions. Thus, a detailed exploration of the regulatory mechanisms of mitophagy is pivotal for enhancing our understanding and for the discovery of novel preventive and therapeutic options for these diseases. Nanomaterials have become integral in biomedicine and various other sectors, offering advanced solutions for medical uses including biological imaging, drug delivery, and disease diagnostics and therapy. Mitophagy is vital in managing the cellular effects elicited by nanomaterials. This review provides a comprehensive analysis of the molecular mechanisms underpinning mitophagy, underscoring its significant influence on the biological responses of cells to nanomaterials. Nanoparticles can initiate mitophagy via various pathways, among which the PINK1-Parkin pathway is critical for cellular defense against nanomaterial-induced damage by promoting mitophagy. The role of mitophagy in biological effects was induced by nanomaterials, which are associated with alterations in Ca2+ levels, the production of reactive oxygen species, endoplasmic reticulum stress, and lysosomal damage.

Drp1: Focus on Diseases Triggered by the Mitochondrial Pathway

Drp1 (Dynamin-Related Protein 1) is a cytoplasmic GTPase protein encoded by the DNM1L gene that influences mitochondrial dynamics by mediating mitochondrial fission processes. Drp1 has been demonstrated to play an important role in a variety of life activities such as cell survival, proliferation, migration, and death. Drp1 has been shown to play different physiological roles under different physiological conditions, such as normal and inflammation. Recently studies have revealed that Drp1 plays a critical role in the occurrence, development, and aggravation of a series of diseases, thereby it serves as a potential therapeutic target for them. In this paper, we review the structure and biological properties of Drp1, summarize the biological processes that occur in the inflammatory response to Drp1, discuss its role in various cancers triggered by the mitochondrial pathway and investigate effective methods for targeting Drp1 in cancer treatment. We also synthesized the phenomena of Drp1 involving in the triggering of other diseases. The results discussed herein contribute to our deeper understanding of mitochondrial kinetic pathway-induced diseases and their therapeutic applications. It is critical for advancing the understanding of the mechanisms of Drp1-induced mitochondrial diseases and preventive therapies.

Autophagy: a necessary evil in cancer and inflammation

Autophagy, a highly regulated cellular process, assumes a dual role in the context of cancer. On the one hand, it functions as a crucial homeostatic pathway, responsible for degrading malfunctioning molecules and organelles, thereby maintaining cellular health. On the other hand, its involvement in cancer development and regression is multifaceted, contingent upon a myriad of factors. This review meticulously examines the intricacies of autophagy, from its molecular machinery orchestrated by Autophagy-Related Genes (ATG) initially discovered in yeast to the various modes of autophagy operative within cells. Beyond its foundational role in cellular maintenance, autophagy reveals context-specific functions in processes like angiogenesis and inflammation. Our analysis delves into how autophagy-related factors directly impact inflammation, underscoring their profound implications for cancer dynamics. Additionally, we extend our inquiry to explore autophagy's associations with cardiovascular conditions, neurodegenerative disorders, and autoimmune diseases, illuminating the broader medical relevance of this process. Furthermore, this review elucidates how autophagy contributes to sustaining hallmark cancer features, including stem cell maintenance, proliferation, angiogenesis, metastasis, and metabolic reprogramming. Autophagy emerges as a pivotal process that necessitates careful consideration in cancer treatment strategies. To this end, we investigate innovative approaches, ranging from enzyme-based therapies to MTOR inhibitors, lysosomal blockers, and nanoparticle-enabled interventions, all aimed at optimizing cancer treatment outcomes by targeting autophagy pathways. In summary, this comprehensive review provides a nuanced perspective on the intricate and context-dependent role of autophagy in cancer biology. Our exploration not only deepens our understanding of this fundamental process but also highlights its potential as a therapeutic target. By unraveling the complex interplay between autophagy and cancer, we pave the way for more precise and effective cancer treatments, promising better outcomes for patients.

Gold Nanoparticles in Neurological Diseases: A Review of Neuroprotection

This review explores the diverse applications of gold nanoparticles (AuNPs) in neurological diseases, with a specific focus on Alzheimer's disease (AD), Parkinson's disease (PD), and stroke. The introduction highlights the pivotal role of neuroinflammation in these disorders and introduces the unique properties of AuNPs. The review's core examines the mechanisms by which AuNPs exert neuroprotection and anti-neuro-inflammatory effects, elucidating various pathways through which they manifest these properties. The potential therapeutic applications of AuNPs in AD are discussed, shedding light on promising avenues for therapy. This review also explores the prospects of utilizing AuNPs in PD interventions, presenting a hopeful outlook for future treatments. Additionally, the review delves into the potential of AuNPs in providing neuroprotection after strokes, emphasizing their significance in mitigating cerebrovascular accidents' aftermath. Experimental findings from cellular and animal models are consolidated to provide a comprehensive overview of AuNPs' effectiveness, offering insights into their impact at both the cellular and in vivo levels. This review enhances our understanding of AuNPs' applications in neurological diseases and lays the groundwork for innovative therapeutic strategies in neurology.

Two-Dimensional Biodegradable Black Phosphorus Nanosheets Promote Large Full-Thickness Wound Healing through In Situ Regeneration Therapy

Large full-thickness skin lesions have been one of the most challenging clinical problems in plastic surgery repair and reconstruction. To achieve in situ skin regeneration and perfect clinical outcomes, we must address two significant obstacles: angiogenesis deficiency and inflammatory dysfunction. Recently, black phosphorus has shown great promise in wound healing. However, few studies have explored the bio-effects of BP to promote in situ skin regeneration based on its nanoproperties. Here, to investigate whether black phosphorus nanosheets have positive bio-effects on in situ skin repair, we verified black phosphorus nanosheets' positive effects on angiogenic and anti-inflammatory abilities in vitro. Next, the in vivo evaluation performed on the rat large full-thickness excisional wound splinting model more comprehensively showed that the positive bio-effects of black phosphorus nanosheets are multilevel in wound healing, which can effectively enhance anti-inflammatory ability, angiogenesis, collagen deposition, and skin re-epithelialization. Then, multiomics analysis was performed to explore further the mechanism of black phosphorus nanosheets' regulation of endothelial cells in depth. Molecular mechanistically, black phosphorus nanosheets activated the JAK-STAT-OAS signaling pathway to promote cellular function and mitochondrial energy metabolism in endothelial cells. This study can provide a theoretical basis for applying two-dimensional black phosphorus nanosheets as nanomedicine to achieve in situ tissue regeneration in complex human pathological microenvironments, guiding the subsequent optimization of black phosphorus.

Crucial physicochemical factors mediating mitochondrial toxicity of nanoparticles at noncytotoxic concentration

Nanomaterials have been extensively applied in multiple industries, among which silver nanoparticles (AgNPs), silicon dioxide nanoparticles (SiNPs), and gold nanoparticles (AuNPs) have become representative of widely consumed NPs. Limited knowledge is available regarding the subcellular responses of NPs with different physicochemical properties, i.e. material type and size, under the noncytotoxic concentrations. Macrophages are important sensitive cells exposed to NPs, and mitochondria are sensitive organelles that respond at the subcellular level. Herein, we found that sublethal concentrations of AgNPs and SiNPs, not AuNPs, decreased the mitochondrial membrane potential (MMP) and tubular mitochondria, and further resulted in an increase of ROS level and a decrease of ATP generation. AgNPs and SiNPs can also disturb mitochondrial dynamics manifested as increasing Mfn2 expression and decreasing Drp1 expression. Further assessments for mitochondrial function showed that AgNPs and SiNPs exposure led to a decrease in the gene expressions related to complex I (Ndufa8 and Ndufs2), complex III (Uqcrc2 and Uqcrfs1), complex IV (Cox6b1), and activity of complex I, suggesting their potential roles in impairing cellular respiration. In terms of the effects of NPs with different sizes, stronger toxicity was observed in smaller-sized nanoparticles. Among the above mitochondrial changes, we identified that ROS, ATP, MMP, tubular mitochondria, and expression of Drp1 were relatively sensitive indicators in subcellular response to NPs. With the above sensitive indicators, the comparison of heterogeneity between material type and size of the NPs showed that material type occupied a main influence on subcellular mitochondrial effects. Our finding provided important data on the potential subcellular risks of NPs, and indicated the vital role of material type for a better understanding of the nanomaterial biological safety.

DMSA-coated IONPs trigger oxidative stress, mitochondrial metabolic reprograming and changes in mitochondrial disposition, hindering cell cycle progression of cancer cells

There is increasing interest in modulating the redox homeostasis of tumors since high levels of reactive oxygen species (ROS) make them more vulnerable to changes in these species. Nanomedicine offers promise in this context as such applications may provoke biological responses that induce ROS production. Indeed, iron oxide nanoparticles (IONPs) can induce ROS accumulation through the so-called Fenton reaction of iron, further augmenting the ROS in tumors and overloading the antioxidant system beyond its capacity, thereby driving oxidative stress to a level that is incompatible with cell survival. Here, three different coatings for IONPs were compared to assess their intrinsic capacity to induce ROS production in cells. Of these coatings, dimercaptosuccinic acid-coated IONPs (DMSA-NPs) provoked the strongest ROS production, which was associated with the ability to reprogram the metabolism of cancer cells. This latter phenomenon involved shutting-down oxidative phosphorylation (OXPHOS), shifting mitochondrial morphology towards a more elongated phenotype, reducing the total mitochondrial mass and ultimately, blocking cell proliferation by inducing G0/G1 cell cycle arrest. Consequently, the data obtained highlights the importance of studying the chemical properties of IONPs, presenting DMSA-NPs as a novel tool to induce oxidative stress in cancer cells and alter their cell fate.

Hexavalent-Chromium-Induced Disruption of Mitochondrial Dynamics and Apoptosis in the Liver via the AMPK-PGC-1α Pathway in Ducks

Hexavalent chromium (Cr(VI)) is a hazardous substance that poses significant risks to environmental ecosystems and animal organisms. However, the specific consequences of Cr(VI) exposure in terms of liver damage remain incompletely understood. This study aims to elucidate the mechanism by which Cr(VI) disrupts mitochondrial dynamics, leading to hepatic injury in ducks. Forty-eight healthy 8-day-old ducks were divided into four groups and subjected to diets containing varying doses of Cr(VI) (0, 9.28, 46.4, and 232 mg/kg) for 49 days. Our results demonstrated that Cr(VI) exposure resulted in disarranged liver lobular vacuolation, along with increasing the serum levels of ALT, AST, and AKP in a dose-dependent manner, which indicated liver damage. Furthermore, Cr(VI) exposure induced oxidative stress by reducing the activities of T-SOD, SOD, GSH-Px, GSH, and CAT, while increasing the contents of MDA and H2O2. Moreover, Cr(VI) exposure downregulated the activities of CS and MDH, resulting in energy disturbance, as evidenced by the reduced AMPK/p-AMPK ratio and PGC-1α protein expression. Additionally, Cr(VI) exposure disrupted mitochondrial dynamics through decreased expression of OPA1, Mfn1, and Mfn2 and increased expression of Drp-1, Fis1, and MFF proteins. This disruption ultimately triggered mitochondria-mediated apoptosis, as evidenced by elevated levels of caspase-3, Cyt C, and Bax, along with decreased expression of Bcl-2 and the Bcl-2/Bax ratio, at both the protein and mRNA levels. In summary, this study highlights that Cr(VI) exposure induces oxidative stress, inhibits the AMPK-PGC-1α pathway, disrupts mitochondrial dynamics, and triggers liver cell apoptosis in ducks.

Dual role of autophagy for advancements from conventional to new delivery systems in cancer

Autophagy, a programmed cell-lysis mechanism, holds significant promise in the prevention and treatment of a wide range of conditions, including cancer, Alzheimer's, and Parkinson's disease. The successful utilization of autophagy modulation for therapeutic purposes hinges upon accurately determining the role of autophagy in disease progression, whether it acts as a cytotoxic or cytoprotective factor. This critical knowledge empowers scientists to effectively manipulate tumor sensitivity to anti-cancer therapies through autophagy modulation, while also circumventing drug resistance. However, conventional therapies face limitations such as low bioavailability, poor solubility, and a lack of controlled release mechanisms, hindering their clinical applicability. In this regard, innovative nanoplatforms including organic and inorganic systems have emerged as promising solutions to offer stimuli-responsive, theranostic-controlled drug delivery systems with active targeting and improved solubility. The review article explores a variety of organic nanoplatforms, such as lipid-based, polymer-based, and DNA-based systems, which incorporate autophagy-inhibiting drugs like hydroxychloroquine. By inhibiting the glycolytic pathway and depriving cells of essential nutrients, these platforms exhibit tumor-suppressive effects in advanced forms of cancer such as leukemia, colon cancer, and glioblastoma. Furthermore, metal-based, metal-oxide-based, silica-based, and quantum dot-based nanoplatforms selectively induce autophagy in tumors, leading to extensive cancer cell destruction. Additionally, this article discusses the current clinical status of autophagy-modulating drugs for cancer therapy with valuable insights of progress and potential of such approaches.

Metallodrugs in the battle against non-small cell lung cancer: unlocking the potential for improved therapeutic outcomes

Non-small cell lung cancer (NSCLC) remains a leading cause of cancer mortality worldwide. Platinum-based chemotherapy is standard-of-care but has limitations including toxicity and resistance. Metal complexes of gold, ruthenium, and other metals have emerged as promising alternatives. This review provides a comprehensive analysis of metallodrugs for NSCLC. Bibliometric analysis reveals growing interest in elucidating mechanisms, developing targeted therapies, and synergistic combinations. Classification of metallodrugs highlights platinum, gold, and ruthenium compounds, as well as emerging metals. Diverse mechanisms include DNA damage, redox modulation, and immunomodulation. Preclinical studies demonstrate cytotoxicity and antitumor effects in vitro and in vivo, providing proof-of-concept. Clinical trials indicate platinums have utility but resistance remains problematic. Non-platinum metallodrugs exhibit favorable safety but modest single agent efficacy to date. Drug delivery approaches like nanoparticles show potential to enhance therapeutic index. Future directions include optimization of metal-based complexes, elucidation of resistance mechanisms, biomarker development, and combination therapies to fully realize the promise of metallodrugs for NSCLC.

Functionalized and Nonfunctionalized Nanosystems for Mitochondrial Drug Delivery with Metallic Nanoparticles

Background: The application of metallic nanoparticles as a novel therapeutic tool has significant potential to facilitate the treatment and diagnosis of mitochondria-based disorders. Recently, subcellular mitochondria have been trialed to cure pathologies that depend on their dysfunction. Nanoparticles made from metals and their oxides (including gold, iron, silver, platinum, zinc oxide, and titanium dioxide) have unique modi operandi that can competently rectify mitochondrial disorders. Materials: This review presents insight into the recent research reports on exposure to a myriad of metallic nanoparticles that can alter the dynamic ultrastructure of mitochondria (via altering metabolic homeostasis), as well as pause ATP production, and trigger oxidative stress. The facts and figures have been compiled from more than a hundred PubMed, Web of Science, and Scopus indexed articles that describe the essential functions of mitochondria for the management of human diseases. Result: Nanoengineered metals and their oxide nanoparticles are targeted at the mitochondrial architecture that partakes in the management of a myriad of health issues, including different cancers. These nanosystems not only act as antioxidants but are also fabricated for the delivery of chemotherapeutic agents. However, the biocompatibility, safety, and efficacy of using metal nanoparticles is contested among researchers, which will be discussed further in this review.

Advances in tumor nanotechnology: theragnostic implications in tumors via targeting regulated cell death

Cell death constitutes an indispensable part of the organismal balance in the human body. Generally, cell death includes regulated cell death (RCD) and accidental cell death (ACD), reflecting the intricately molecule-dependent process and the uncontrolled response, respectively. Furthermore, diverse RCD pathways correlate with multiple diseases, such as tumors and neurodegenerative diseases. Meanwhile, with the development of precision medicine, novel nano-based materials have gradually been applied in the clinical diagnosis and treatment of tumor patients. As the carrier, organic, inorganic, and biomimetic nanomaterials could facilitate the distribution, improve solubility and bioavailability, enhance biocompatibility and decrease the toxicity of drugs in the body, therefore, benefiting tumor patients with better survival outcomes and quality of life. In terms of the most studied cell death pathways, such as apoptosis, necroptosis, and pyroptosis, plenty of studies have explored specific types of nanomaterials targeting the molecules and signals in these pathways. However, no attempt was made to display diverse nanomaterials targeting different RCD pathways comprehensively. In this review, we elaborate on the potential mechanisms of RCD, including intrinsic and extrinsic apoptosis, necroptosis, ferroptosis, pyroptosis, autophagy-dependent cell death, and other cell death pathways together with corresponding nanomaterials. The thorough presentation of RCD pathways and diverse nano-based materials may provide a wider cellular and molecular landscape of tumor diagnosis and treatments.

Zinc oxide nanoparticles trigger dysfunction of mitochondrial respiratory complexes and repair dynamics in human alveolar cells

Zinc oxide nanoparticles (ZnO NP) are commonly used engineered NPs with extensive usage in consumer products, thus leading to direct exposure to humans. The direct route of exposure is through inhalation. Once inhaled, these particles accumulate in the lungs, increasing the chances of respiratory tract illness through cellular organelle damage. Zinc oxide nanoparticle-treated lung cells are reported to display cytotoxicity, increase DNA damage, and induce oxidative stress. The current study focused on the effects of ZnO NPs on mitochondrial dynamics (fission and fusion) in human lung epithelial cells (A549). The lung cells were exposed to ZnO NPs at 50 and 100 μg/ml concentrations, and their mitochondrial dynamics were assessed to understand the effects of the NPs. Treatment with ZnO NPs reduced the activity of mitochondrial complex I and complex III and altered mitochondrial structural and functional characteristics in a concentration-dependent manner. Zinc oxide nanoparticles exposure showed an increase in small and round-shaped mitochondria. The expression of various fission proteins (Drp1 and Fis1) and fusion proteins (Mfn1, Mfn2, and OPA1) was altered upon exposure to ZnO NPs. Our studies showed dysfunction of the mitochondria induced by ZnO NPs. In fibroblast mitochondrial dynamics, fission symbolizes threshold damage. In this paper, we have shown that the mitochondrial fission phenotype increased upon exposure to ZnO NPs. The paper emphasizes that these particles enter mitochondria, triggering a stress response that results in the removal of mitochondria via fission. It provides relevant data for safety guidelines to ensure the safer use of these particles.

Gold nanoparticles enhance proliferation and osteogenic differentiation of periodontal ligament stem cells by PINK1-mediated mitophagy

OBJECTIVE

Evidence suggests that gold nanoparticles (AuNPs) improve osteogenic differentiation of periodontal ligament stem cells (PDLSCs), PTEN-induced putative kinase 1 (PINK1) dependent mitophagy modulates inter-clonal communication among PDLSCs with osteogenic heterogeneity, but the mechanism remains vague. Therefore, the current research assessed the influence of AuNPs on proliferation, osteogenic differentiation and mitophagy of PDLSCs and the potential mechanism was analyzed.

METHODS

Gold nanospheres with a diameter of 5, 10, 20, 40, and 80 nm were synthesized and characterized through transmission electron microscopy, and rat PDLSCs were isolated using flow sorting. Next, PDLSCs were treated with AuNPs or PINK1 lentivirus to obtain its overexpression or suppression. Proliferation and osteogenic differentiation were evaluated by CCK-8, ALP staining, ARS staining, and immunoblotting of OCN, OPN, RUNX2, ALP, BMP2, and COL1. Mitochondrial quality, homeostasis and quantity were assessed though JC-1 staining, immunoblotting of Tom20, Tim23 and HSP60 and mitochondrial ROS detection. PINK1, Parkin, Beclin1 and LC3 expression was quantified to investigate mitophagy, using RT-qPCR and immunoblotting and the formation of RFP-GFP-LC3-labeled autophagosomes were also measured.

RESULTS

The proliferation ability of PDLSCs almost reached the maximum under 20 nm AuNPs for 24 h. AuNPs enhanced the proliferation and osteogenic differentiation of PDLSCs, improved mitochondrial quality and homeostasis as well as attenuated mitochondrial quantity. Additionally, mitophagy was enhanced by PDLSCs. Activation of PINK1 synergistically enhanced AuNPs-mediated mitophagy, mitochondrial quality, homeostasis and osteogenic differentiation in PDLSCs, obtaining opposite effects when PINK1 was suppressed.

CONCLUSION

AuNPs enhance proliferation and osteogenic differentiation of PDLSCs through PINK1-mediated mitophagy.

Nano-TRAIL: a promising path to cancer therapy

Tumor Necrosis Factor-Related Apoptosis-Inducing Ligand, also called apo-2 ligand (TRAIL/Apo-2L), is a cytokine that triggers apoptosis by binding to TRAIL-R1 (DR4) and TRAIL-R2 (DR5) death receptors. Apoptosis occurs through either the extrinsic or intrinsic pathway. The administration of recombinant human TRAIL (rhTRAIL) or TRAIL-receptor (TRAIL-R) agonists promotes apoptosis preferentially in cancerous cells over normal cells in vitro; this phenomenon has also been observed in clinical studies. The limited efficacy of rhTRAIL in clinical trials could be attributed to drug resistance, short half-life, targeted delivery issues, and off-target toxicities. Nanoparticles are excellent drug and gene delivery systems characterized by improved permeability and retention, increased stability and biocompatibility, and precision targeting. In this review, we discuss resistance mechanisms to TRAIL and methods to overcome TRAIL resistance by using nanoparticle-based formulations developed for the delivery of TRAIL peptides, TRAIL-R agonists, and TRAIL genes to cancer cells. We also discuss combinatorial approaches of chemotherapeutic drugs with TRAIL. These studies demonstrate TRAIL's potential as an anticancer agent.

Self-Therapeutic Nanomaterials: Applications in Biology and Medicine

Over past decades, nanotechnology has contributed to the biomedical field in areas including detection, diagnosis, and drug delivery via opto-electronic properties or enhancement of biological effects. Though generally considered inert delivery vehicles, a plethora of past and present evidence demonstrates that nanomaterials also exude unique intrinsic biological activity based on composition, shape, and surface functionalization. These intrinsic biological activities, termed self-therapeutic properties, take several forms, including mediation of cell-cell interactions, modulation of interactions between biomolecules, catalytic amplification of biochemical reactions, and alteration of biological signal transduction events. Moreover, study of biomolecule-nanomaterial interactions offers a promising avenue for uncovering the molecular mechanisms of biology and the evolution of disease. In this review, we observe the historical development, synthesis, and characterization of self-therapeutic nanomaterials. Next, we discuss nanomaterial interactions with biological systems, starting with administration and concluding with elimination. Finally, we apply this materials perspective to advances in intrinsic nanotherapies across the biomedical field, from cancer therapy to treatment of microbial infections and tissue regeneration. We conclude with a description of self-therapeutic nanomaterials in clinical trials and share our perspective on the direction of the field in upcoming years.

Targeting TRAIL Death Receptors in Triple-Negative Breast Cancers: Challenges and Strategies for Cancer Therapy

The tumor necrosis factor (TNF) superfamily member TNF-related apoptosis-inducing ligand (TRAIL) induces apoptosis in cancer cells via death receptor (DR) activation with little toxicity to normal cells or tissues. The selectivity for activating apoptosis in cancer cells confers an ideal therapeutic characteristic to TRAIL, which has led to the development and clinical testing of many DR agonists. However, TRAIL/DR targeting therapies have been widely ineffective in clinical trials of various malignancies for reasons that remain poorly understood. Triple negative breast cancer (TNBC) has the worst prognosis among breast cancers. Targeting the TRAIL DR pathway has shown notable efficacy in a subset of TNBC in preclinical models but again has not shown appreciable activity in clinical trials. In this review, we will discuss the signaling components and mechanisms governing TRAIL pathway activation and clinical trial findings discussed with a focus on TNBC. Challenges and potential solutions for using DR agonists in the clinic are also discussed, including consideration of the pharmacokinetic and pharmacodynamic properties of DR agonists, patient selection by predictive biomarkers, and potential combination therapies. Moreover, recent findings on the impact of TRAIL treatment on the immune response, as well as novel strategies to address those challenges, are discussed.

Gene prioritization based on random walks with restarts and absorbing states, to define gene sets regulating drug pharmacodynamics from single-cell analyses

Prioritizing genes for their role in drug sensitivity, is an important step in understanding drugs mechanisms of action and discovering new molecular targets for co-treatment. To formalize this problem, we consider two sets of genes X and P respectively composing the gene signature of cell sensitivity at the drug IC50 and the genes involved in its mechanism of action, as well as a protein interaction network (PPIN) containing the products of X and P as nodes. We introduce Genetrank, a method to prioritize the genes in X for their likelihood to regulate the genes in P. Genetrank uses asymmetric random walks with restarts, absorbing states, and a suitable renormalization scheme. Using novel so-called saturation indices, we show that the conjunction of absorbing states and renormalization yields an exploration of the PPIN which is much more progressive than that afforded by random walks with restarts only. Using MINT as underlying network, we apply Genetrank to a predictive gene signature of cancer cells sensitivity to tumor-necrosis-factor-related apoptosis-inducing ligand (TRAIL), performed in single-cells. Our ranking provides biological insights on drug sensitivity and a gene set considerably enriched in genes regulating TRAIL pharmacodynamics when compared to the most significant differentially expressed genes obtained from a statistical analysis framework alone. We also introduce gene expression radars, a visualization tool embedded in MA plots to assess all pairwise interactions at a glance on graphical representations of transcriptomics data. Genetrank is made available in the Structural Bioinformatics Library (https://sbl.inria.fr/doc/Genetrank-user-manual.html). It should prove useful for mining gene sets in conjunction with a signaling pathway, whenever other approaches yield relatively large sets of genes.

Nanotherapeutics in autophagy: a paradigm shift in cancer treatment

Autophagy is a catabolic process in which an organism responds to its nutrient or metabolic emergencies. It involves the degradation of cytoplasmic proteins and organelles by forming double-membrane vesicles called "autophagosomes." They sequester cargoes, leading them to degradation in the lysosomes. Although autophagy acts as a protective mechanism for maintaining homeostasis through cellular recycling, it is ostensibly a cause of certain cancers, but a cure for others. In other words, insufficient autophagy, due to genetic or cellular dysfunctions, can lead to tumorigenesis. However, many autophagy modulators are developed for cancer therapy. Diverse nanoparticles have been documented to induce autophagy. Also, the highly stable nanoparticles show blockage to autophagic flux. In this review, we revealed a general mechanism by which autophagy can be induced or blocked via nanoparticles as well as several studies recently performed to prove the stated fact. In addition, we have also elucidated the paradoxical roles of autophagy in cancer and how their differential role at different stages of various cancers can affect its treatment outcomes. And finally, we summarize the breakthroughs in cancer disease treatments by using metallic, polymeric, and liposomal nanoparticles as potent autophagy modulators.

Mitophagy Induced by Metal Nanoparticles for Cancer Treatment

Research on nanoparticles, especially metal nanoparticles, in cancer therapy is gaining momentum. The versatility and biocompatibility of metal nanoparticles make them ideal for various applications in cancer therapy. They can bring about apoptotic cell death in cancer cells. In addition to apoptosis, nanoparticles mediate a special type of autophagy facilitated through mitochondria called mitophagy. Interestingly, nanoparticles with antioxidant properties are capable of inducing mitophagy by altering the levels of reactive oxygen species and by influencing signaling pathways like PINK/Parkin pathway and P13K/Akt/mTOR pathway. The current review presents various roles of metal nanoparticles in inducing mitophagy in cancer cells. We envision this review sheds some light on the blind spots in the research related to mitophagy induced by nanoparticles for cancer treatment.

Polystyrene micro(nano)plastics damage the organelles of RBL-2H3 cells and promote MOAP-1 to induce apoptosis

The ubiquity of microplastics increases the exposure risks and health threats to humans. In this study, rat basophilic leukemia (RBL-2H3) cells were exposed to polystyrene particles (PS-particles) of 50 nm, 500 nm and 5 µm to investigate organelle damage and the mechanism of cell death. PS-particles induced oxidative stress, which in turn led to mitochondrial and lysosomal damage, arrested the cell cycle in the G0/G1 phase, and finally caused apoptosis. Anti-apoptotic genes (Bcl-2) were down regulated, and pro-apoptotic genes (Bax) and a key gene (caspase-3) in apoptosis were upregulated. The molecular mechanism of apoptosis was further explored via the combination of transcriptome sequencing, RT-qPCR verification and small interfering RNA (siRNA) technology. The modulator of apoptosis-1 (MOAP-1) was significantly upregulated, and apoptosis was abolished by knocking down MOAP-1. This finding clarifies that PS-particles promote MOAP-1 to induce apoptosis. Hence, PS-particles may promote the binding of MOAP-1 and Bax, which ultimately activates caspase-3 and causes apoptosis through the mitochondrial pathway. The 50-nm PS-particles resulted in the most serious mitochondrial damage and apoptosis. Eventually, PS-particles cause oxidative stress, damage organelles and induce apoptosis by promoting MOAP-1. Altogether, our study emphasizes the need to assess the cytotoxicity of micro(nano)plastics and helps to predict the health risks.

Amorphous silica nanoparticles caused lung injury through the induction of epithelial apoptosis via ROS/Ca2+/DRP1-mediated mitochondrial fission signaling

The adverse effects of amorphous silica nanoparticles (SiNPs) exposure on the respiratory system were increasingly recognized, however, its potential pathogenesis still remains not fully elucidated. So, this study aimed to explore its effects on pulmonary injury, and to investigate related mechanisms. Histological investigations illustrated SiNPs triggered the lung injury, mainly manifested as alveolar structure destruction, collagen deposition, and mitochondrial ultrastructural injury. In particular, SiNPs greatly enhanced pulmonary ROS and TUNEL positive rate in lungs, both of which were positively correlated with lung impairments. Further, the underlying mechanisms were investigated in cultured human bronchial epithelial cells (16HBE). Consistent with the in vivo findings, SiNPs caused the impairments on mitochondrial structure, as well as the activation of ROS generation and oxidative injury. Upon SiNPs stimuli, mitochondrial respiration was greatly inhibited, while Ca2+ overload in cytosol and mitochondria owing to ER calcium release was noticed, resulting in mitochondrial-dependent epithelial apoptosis. More importantly, mitochondrial dynamics was imbalanced toward a fission type, as evidenced by upregulated DRP1 and its phosphorylation at Ser616 (DRP1s616), while downregulated DRP1s637, and also MFN1, MFN2. Mechanistic investigations revealed that the activation of ROS/Ca2+ signaling promoted DRP1-mediated mitochondrial fission by SiNPs, forming a vicious cycle, and ultimately contributing to apoptosis in 16HBE. In summary, our results disclosed SiNPs caused pulmonary injury through the induction of epithelial apoptosis via a ROS/Ca2+/DRP1-mediated mitochondrial fission axis.

Nanoparticle Effects on Stress Response Pathways and Nanoparticle-Protein Interactions

Nanoparticles (NPs) are increasingly used in a wide variety of applications and products; however, NPs may affect stress response pathways and interact with proteins in biological systems. This review article will provide an overview of the beneficial and detrimental effects of NPs on stress response pathways with a focus on NP-protein interactions. Depending upon the particular NP, experimental model system, and dose and exposure conditions, the introduction of NPs may have either positive or negative effects. Cellular processes such as the development of oxidative stress, the initiation of the inflammatory response, mitochondrial function, detoxification, and alterations to signaling pathways are all affected by the introduction of NPs. In terms of tissue-specific effects, the local microenvironment can have a profound effect on whether an NP is beneficial or harmful to cells. Interactions of NPs with metal-binding proteins (zinc, copper, iron and calcium) affect both their structure and function. This review will provide insights into the current knowledge of protein-based nanotoxicology and closely examines the targets of specific NPs.

Effect of Titanium Dioxide and Silver Nanoparticles on Mitochondrial Dynamics in Mouse Testis Tissue

This study was performed to investigate whether the toxicity of nanoparticles (Ag NPs or TiO₂ NPs) affected mitochondrial dynamics (mitochondrial fusion and fission mechanisms) in testicular cells of mice. Animals were assigned into three groups (ten mice per group): control group (distilled water), TiO₂ NP group (5 mg/kg per dose), and Ag NP group (5 mg/kg per dose). NPs were administered intravenously (via tail vein) to mice with 3-day intervals. To determine the possible toxic effect of NPs on mitochondrial dynamics, the expression levels of mitochondrial fission (Drp1)- and fusion (Mfn1, Mfn2, OPA1)-related genes were analyzed. The results showed that both Ag NPs and TiO₂ NPs entered the testis via the blood-testis barier and accumulated in mouse testis tissue. Experiments showed that administration of Ag NPs neither alters testicular weight and testicular index nor causes significant toxic effect on sperm parameters. RT-PCR analysis demonstrated that Ag NP treatment did not disrupt mitochondrial dynamics in testicular cells. Conversely, administration of TiO₂ NPs (anatase, < 25 nm) decreased the sperm motility and the percentages of sperms with swollen tail. Furthermore, RT-PCR and western blot analyses showed that TiO₂ NPs disrupted mitochondrial dynamics by causing excess mitochondrial fission (excess expression of Drp1 gene and DRP1 protein). This is the first report on the toxicity of nanoparticles on mitochondrial dynamics (fusion and fission mechanisms) in testicular cells.

Intracellular reactive oxygen species trigger mitochondrial dysfunction and apoptosis in cadmium telluride quantum dots-induced liver damage

Quantum dots (QDs), also known as semiconductor QDs, have specific photoelectricproperties which find application in bioimaging, solar cells, and light-emitting diodes (LEDs). However, the application of QDs is often limited by issues related to health risks and potential toxicity. The purpose of this study was to provide evidence regarding the safety of cadmium telluride (CdTe) QDs by exploring the detailed mechanisms involved in its hepatotoxicity. This study showed that CdTe QDs can increase reactive oxygen species (ROS) in hepatocytes after being taken up by hepatocytes, which triggers a significant mitochondrial-dependent apoptotic pathway, leading to hepatocyte apoptosis. CdTe QDs-induce mitochondrial cristae abnormality, adenosine triphosphate (ATP) depletion, and mitochondrial membrane potential (MMP) depolarization. Meanwhile, CdTe QDs can change the morphology, function, and quantity of mitochondria by reducing fission and intimal fusion. Importantly, inhibition of ROS not only protects hepatocyte viability but can also interfere with apoptosis and activation of mitochondrial dysfunction. Similarly, the exposure of CdTe QDs in Institute of Cancer Research (ICR) mice showed that CdTe QDs caused oxidative damage and apoptosis in liver tissue. NAC could effectively remove excess ROS could reduce the level of oxidative stress and significantly alleviate CdTe QDs-induced hepatotoxicity in vivo. CdTe QDs-induced hepatotoxicity may originate from the generation of intracellular ROS, leading to mitochondrial dysfunction and apoptosis, which was potentially regulated by mitochondrial dynamics. This study revealed the nanobiological effects of CdTe QDs and the intricate mechanisms involved in its toxicity at the tissue, cell, and subcellular levels and provides information for narrowing the gap between in vitro and in vivo animal studies and a safety assessment of QDs.

Peanut-Shaped Gold Nanoparticles with Shells of Ceragenin CSA-131 Display the Ability to Inhibit Ovarian Cancer Growth In Vitro and in a Tumor Xenograft Model

Simple Summary

Despite a spectrum of therapeutics available for the treatment of ovarian tumors, there is a constant need to develop novel treatment options, particularly due to a high incidence of drug resistant tumors and low 5-year survival of patients diagnosed with ovarian carcinomas. In this study, we employed a nanotechnology-based approach to present a novel nanosystem based on ceragenin CSA-131 attached to the surface of a peanut-shaped gold nanoparticle. We demonstrate that such a prepared nanoformulation was highly effective against ovarian cancer cells in in vitro settings and, with limited toxicity, was able to prevent the growth of ovarian tumors in treated animals. Based on obtained data we suggest that ceragenin-containing nanosystems should be considered and further tested as potential therapeutics for ovarian malignancy.

Abstract

Gold nanoparticles-assisted delivery of antineoplastics into cancerous cells is presented as an effective approach for overcoming the limitations of systemic chemotherapy. Although ceragenins show great potential as anti-cancer agents, in some tumors, effective inhibition of cancer cells proliferation requires application of ceragenins at doses within their hemolytic range. For the purpose of toxicity/efficiency ratio control, peanut-shaped gold nanoparticles (AuP NPs) were functionalized with a shell of ceragenin CSA-131 and the cytotoxicity of AuP@CSA-131 against ovarian cancer SKOV-3 cells and were then analyzed. In vivo efficiency of intravenously and intratumorally administered CSA-131 and AuP@CSA-131 was examined using a xenograft ovarian cancer model. Serum parameters were estimated using ELISA methods. Comparative analysis revealed that AuP@CSA-131 exerted stronger anti-cancer effects than free ceragenin, which was determined by enhanced ability to induce caspase-dependent apoptosis and autophagy processes via reactive oxygen species (ROS)-mediated pathways. In an animal study, AuP@CSA-131 was characterized by delayed clearance and prolonged blood circulation when compared with free ceragenin, as well as enhanced anti-tumor efficiency, particularly when applied intratumorally. Administration of CSA-131 and AuP@CSA-131 prevented the inflammatory response associated with cancer development. These results present the possibility of employing non-spherical gold nanoparticles as an effective nanoplatform for the delivery of antineoplastics for the treatment of ovarian malignancy.

TRAIL Conjugated Silver Nanoparticle Synthesis, Characterization and Therapeutic Effects on HT-29 Colon Cancer Cells

Colon cancer is one of the most prominent causes of cancer-related morbidity and mortality and curable if detected in the early stages. TNF-related apoptosis-inducing ligand (TRAIL) is a therapeutic protein and has a potential anti-cancer activity that is widely used for the treatment of several cancers. In this study, we aimed to develop a silver nanoparticle system conjugated with TRAIL and coated with PEG (AgCTP NPs) to improve the therapeutic effects of colon cancer. AgCTP NPs were characterized by UV spectrum, FTIR and zetasizer. Cytotoxicity, hemolysis assay and apoptotic effects of nanoparticles were investigated using a colon cancer cell line (HT-29) in-vitro. Treatment with AgCTP NPs effectively inhibited proliferation and colony formation of HT-29 cells. The apoptotic effects of nanoparticles on HT-29 cells were determined as Bax, Bcl-2, PARP and clv-PARP protein expression levels using Western blot. Apoptotic proteins were upregulated by AgCTP NPs. In this study, we demonstrated that AgCTP NPs had an anti-cancer effect by activating cell death. Thus, we have confirmed that silver nanoparticles can be selected as a good carrier for TRAIL therapeutic proteins that can be used to treat colon cancer.

Harnessing TRAIL-Induced Apoptosis Pathway for Cancer Immunotherapy and Associated Challenges

The immune cytokine tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) has attracted rapidly evolving attention as a cancer treatment modality because of its competence to selectively eliminate tumor cells without instigating toxicity in vivo. TRAIL has revealed encouraging promise in preclinical reports in animal models as a cancer treatment option; however, the foremost constraint of the TRAIL therapy is the advancement of TRAIL resistance through a myriad of mechanisms in tumor cells. Investigations have documented that improvement of the expression of anti-apoptotic proteins and survival or proliferation involved signaling pathways concurrently suppressing the expression of pro-apoptotic proteins along with down-regulation of expression of TRAILR1 and TRAILR2, also known as death receptor 4 and 5 (DR4/5) are reliable for tumor cells resistance to TRAIL. Therefore, it seems that the development of a therapeutic approach for overcoming TRAIL resistance is of paramount importance. Studies currently have shown that combined treatment with anti-tumor agents, ranging from synthetic agents to natural products, and TRAIL could result in induction of apoptosis in TRAIL-resistant cells. Also, human mesenchymal stem/stromal cells (MSCs) engineered to generate and deliver TRAIL can provide both targeted and continued delivery of this apoptosis-inducing cytokine. Similarly, nanoparticle (NPs)-based TRAIL delivery offers novel platforms to defeat barricades to TRAIL therapeutic delivery. In the current review, we will focus on underlying mechanisms contributed to inducing resistance to TRAIL in tumor cells, and also discuss recent findings concerning the therapeutic efficacy of combined treatment of TRAIL with other antitumor compounds, and also TRAIL-delivery using human MSCs and NPs to overcome tumor cells resistance to TRAIL.

Purification of olive mill wastewater through noble metal nanoparticle synthesis: waste safe disposal and nanomaterial impact on healthy hepatic cell mitochondria

The exponential increase of waste derived from different human activities points out the importance of their reuse in order to create materials with specific properties that can be used for different applications. In this work, it was showed how the typical Mediterranean organic liquid waste, namely olive mill wastewater (OMWW), obtained during olive oil production, can be turned into an efficient reactive agent for the production of noble metals gold (Au) and silver nanoparticles (Ag NPs) with very well-defined physico-chemical properties. More than that, it was demonstrated that this synthetic procedure also leads to a drastic decrease of the organic pollution load of the OMWW, making it safer for environmental disposal and plants irrigation. Then, using healthy hepatic cell line mitochondria, the biological effects induced by these green metal NPs surrounded by a polyphenols shell, with the same NPs synthetized through a standard chemical colloidal reduction process, were compared, finding out that the green NPs are much safer.

Mitochondrial dynamics and mitophagy involved in MPA-capped CdTe quantum dots-induced toxicity in the human liver carcinoma (HepG2) cell line

Quantum dots (QDs) are nanoparticles of inorganic semiconductors and have great promise in various applications. Many studies have indicated that mitochondria are the main organelles for the distribution and toxic effects of QDs. However, the underlying mechanism of QDs interacting with mitochondria and affecting their function is unknown. Here, we report the mechanism of toxic effects of 3-mercaptopropionic acid (MPA)-capped CdTe QDs on mitochondria. Human liver carcinoma (HepG2) cells were exposed to 25, 50 and 100 μmol/L of MPA-capped CdTe QDs. The results indicated that MPA-capped CdTe QDs inhibited HepG2 cell proliferation and increased the extracellular release of LDH in a concentration-dependent manner. Furthermore, MPA-capped CdTe QDs caused reactive oxygen species (ROS) generation and cell damage through intrinsic apoptotic pathway. MPA-capped CdTe QDs can also lead to the destruction of mitochondrial cristae, elevation of intracellular Ca²⁺ levels, decreased mitochondrial transmembrane potential and ATP production. Finally, we showed that MPA-capped CdTe QDs inhibited mitochondrial fission, mitochondrial inner membrane fusion and mitophagy. Taken together, MPA-capped CdTe QDs induced significant mitochondrial dysfunction, which may be caused by imbalanced mitochondrial fission/fusion and mitophagy inhibition. These findings provide insights into the regulatory mechanisms involved in MPA-capped CdTe QDs-induced mitochondrial dysfunction.

Targeting the Dysfunctional Placenta to Improve Pregnancy Outcomes Based on Lessons Learned in Cancer

In recent decades, our understanding of the disrupted mechanisms that contribute to major obstetrical diseases, including preeclampsia, fetal growth restriction, preterm birth, and gestational diabetes, has increased exponentially. Common to many of these obstetric diseases is placental maldevelopment and dysfunction; the placenta is a significant component of the maternal-fetal interface involved in coordinating, facilitating, and regulating maternal and fetal nutrient, oxygen and waste exchange, and hormone and cytokine production. Despite the advances in our understanding of placental development and function, there are currently no treatments for placental maldevelopment and dysfunction. However, given the transient nature and accessibility from the maternal circulation, the placenta offers a unique opportunity to develop targeted therapeutics for routine obstetric practices. Furthermore, given the similar developmental paradigms between the placenta and cancer, there is an opportunity to appropriate current knowledge from advances in targeted therapeutics in cancer treatments. In this review, we highlight the similarities between early placental development and cancer and introduce a number of targeted therapies currently being explored in cancer and pregnancy. We also propose a number of new effectors currently being targeted in cancer research that have the potential to be targeted in the development of treatments for pregnancy complications. Finally, we describe a method for targeting the placenta using nonviral polymers that are capable of delivering plasmids, small interfering RNA, and other effector nucleic acids, which could ultimately improve fetal and maternal outcomes from complicated pregnancies.

Gold nanomaterials in the management of lung cancer

Lung cancer (LC) is one of the most deadly cancers worldwide, with very low survival rates, mainly due to poor management, which has barely changed in recent years. Nanomedicines, especially gold nanomaterials, with their unique and size-dependent properties offer a potential solution to many challenges in the field. The versatility afforded by the shape, size, charge and surface chemistry of gold nanostructures allows them to be adapted for many applications in the diagnosis, treatment and imaging of LC. In this review, a survey of the most recent advances in the field is presented with an emphasis on the optical properties of gold nanoscale materials and their use in cancer management. Gold nanoparticle toxicology has also been a focus of interest for many years but the studies have also sometimes arrived at contradictory conclusions. To enable extrapolation and facilitate the development of medicines based on gold nanomaterials, it must be assumed that each design will have its own unique characteristics that require evaluation before translation to the clinic. Advances in the understanding and recognition of the molecular signatures of LC have aided the development of personalised medicines. Tailoring the treatment to each case should, ideally increase the survival outcomes as well as reduce medical costs. This review seeks to present the potential of gold nanomaterials in LC management and to provide a unified view, which will be of interest to those in the field as well as researchers considering entering this highly important area of research.

TRAIL of Hope Meeting Resistance in Cancer

Tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) induces apoptosis selectively via its interaction with the death receptors TRAILR1/DR4 and TRAILR2/DR5 in a wide range of cancers, while sparing normal cells. Despite its tremendous potential for cancer therapeutics, the translation of TRAIL into the clinic has been confounded by TRAIL-resistant cancer populations. We discuss different molecular mechanisms underlying TRAIL-mediated apoptosis and resistance to TRAIL. We also discuss the successes and failures of recent preclinical and clinical studies of TRAIL-induced apoptosis, and current attempts to overcome TRAIL resistance, and we provide a perspective for improving the prospects of future clinical implementation.

Targeted drug therapy in nonsmall cell lung cancer: clinical significance and possible solutions-part II (role of nanocarriers)

INTRODUCTION

Nonsmall cell lung cancer (NSCLC) accounts for 80-85% of the cases of lung cancer. The conventional therapeutic effective dosage forms used to treat NSCLC are associated with rigid administration schedules, adverse effects, and may be associated with acquired resistance to therapy. Nanocarriers may provide a suitable alternative to regular formulations to overcome inherent drawbacks and provide better treatment modalities for the patient.

AREAS COVERED

The article explores the application of drug loaded nanocarriers for lung cancer treatment. Drug-loaded nanocarriers can be modified to achieve controlled delivery at the desired tumor infested site. The type of nanocarriers employed are diverse based on polymers, liposomes, metals and a combination of two or more different base materials (hybrids). These may be designed for systemic delivery or local delivery to the lung compartment (via inhalation).

EXPERT OPINION

Nanocarriers can improve pharmacokinetics of the drug payload by improving its delivery to the desired location and can reduce associated systemic toxicities. Through nanocarriers, a wide variety of therapeutics can be administered and targeted to the cancerous site. Some examples of the utilities of nanocarriers are codelivery of drugs, gene delivery, and delivery of other biologics. Overall, the nanocarriers have promising potential in improving therapeutic efficacy of drugs used in NSCLC.

Luteolin enhances TRAIL sensitivity in non-small cell lung cancer cells through increasing DR5 expression and Drp1-mediated mitochondrial fission

Cancer cells exhibit extreme sensitivity to tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) over normal cells, highlighting TRAIL's potential as a novel and effective cancer drug. However, the therapeutic effect of TRAIL is limited due to drug resistance. In the present study, we sought to investigate the potential effects of luteolin as a TRAIL sensitizer in non-small cell lung cancer (NSCLC) cells. A549 and H1975 cells had low sensitivity or were resistant to TRAIL. Luteolin alone or in combination with TRAIL decreased cell viability and increased apoptosis. Furthermore, luteolin alone or in combination with TRAIL enhanced death receptor 5 (DR5) expression and dynamin-related protein 1 (Drp1)-dependent mitochondrial fission. However, the synergistic effect of luteolin on cell viability and apoptosis was reversed by DR5 and Drp1 inhibition, suggesting that DR5 upregulation and mitochondrial dynamics may be essential for luteolin as a sensitizer of TRAIL-based therapy in NSCLC. Moreover, luteolin treatment alone or in combination with TRAIL increased the phosphorylation of c-Jun N-terminal kinase (JNK), while SP600125 (the JNK inhibitor) significantly abolished the synergistic effect on DR5 expression and Drp1 translocation, indicating that JNK signaling activation was greatly associated with the synergistic effect exerted by luteolin in NSCLC cells. Therefore, TRAIL combined with luteolin could be as an effective chemotherapeutic strategy for NSCLC.

TRAIL-conjugated silver nanoparticles sensitize glioblastoma cells to TRAIL by regulating CHK1 in the DNA repair pathway

OBJECTIVES

Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) selectively triggers apoptosis in cancer cells, but not in normal cells. Resistance of glioblastoma cells to TRAIL is a major obstacle for successful clinical treatment of TRAIL. Thus, there is an essential requirement for novel approaches to sensitize TRAIL resistance. Silver nanoparticles (AgNPs) are one of the most promising nanomaterials that show immense antitumor potential via targeting various cellular and molecular processes; however, the effects of AgNPs on TRAIL sensitivity in cancer cells remain unclear. Therefore, we hypothesized that TRAIL-conjugated AgNPs (TRAIL-AgNPs) can overcome TRAIL resistance through inducing death receptor activation in glioblastoma cells, but not normal cells.

METHODS

In this study, the therapeutic effect of TRAIL-AgNPs is investigated by analyzing the cell viability, caspase activity, and CHK1 gene expression in T98 G TRAIL-Sensitive (TS) and T98 G TRAIL-Resistant (TR) glioblastoma cells.

RESULTS

It is found that TRAIL-AgNPs are more toxic compared to TRAIL and AgNPs treatments alone on TR cells. While TRAIL and AgNPs alone do not enhance the caspase activity, conjugation of TRAIL to AgNPs increases the caspase activity in TR cells. Moreover, the TRAIL-AgNPs-treated TR cells show less CHK1 expression compared to the TRAIL treatment.

CONCLUSION

These results suggest that TRAIL sensitivity of TR cells can be enhanced by conjugation of TRAIL with AgNPs, which would be a novel therapeutic approach to sensitize TRAIL resistance.

Crosstalks between inflammasome and autophagy in cancer

Both inflammasomes and autophagy have important roles in the intracellular homeostasis, inflammation, and pathology; the dysregulation of these processes is often associated with the pathogenesis of numerous cancers. In addition, they can crosstalk with each other in multifaceted ways to influence various physiological and pathological responses, including cancer. Multiple molecular mechanisms connect the autophagy pathway to inflammasome activation and, through this, may influence the outcome of pro-tumor or anti-tumor responses depending on the cancer types, microenvironment, and the disease stage. In this review, we highlight the rapidly growing literature on the various mechanisms by which autophagy interacts with the inflammasome pathway, to encourage additional applications in the context of tumors. In addition, we provide insight into the mechanisms by which pathogen modulates the autophagy-inflammasome pathway to favor the infection-induced carcinogenesis. We also explore the challenges and opportunities of using multiple small molecules/agents to target the autophagy/inflammasome axis and their effects upon cancer treatment. Finally, we discuss the emerging clinical efforts assessing the potential usefulness of targeting approaches for either autophagy or inflammasome as anti-cancer strategies, although it remains underexplored in terms of their crosstalks.

TRAIL therapy and prospective developments for cancer treatment

Tumor Necrosis Factor (TNF) Related Apoptosis-Inducing Ligand (TRAIL), an immune cytokine of TNF-family, has received much attention in late 1990s as a potential cancer therapeutics due to its selective ability to induce apoptosis in cancer cells. TRAIL binds to cell surface death receptors, TRAIL-R1 (DR4) and TRAIL-R2 (DR5) and facilitates formation of death-inducing signaling complex (DISC), eventually activating the p53-independent apoptotic cascade. This unique mechanism makes the TRAIL a potential anticancer therapeutic especially for p53-mutated tumors. However, recombinant human TRAIL protein (rhTRAIL) and TRAIL-R agonist monoclonal antibodies (mAb) failed to exert robust anticancer activities due to inherent and/or acquired resistance, poor pharmacokinetics and weak potencies for apoptosis induction. To get TRAIL back on track as a cancer therapeutic, multiple strategies including protein modification, combinatorial approach and TRAIL gene therapy are being extensively explored. These strategies aim to enhance the half-life and bioavailability of TRAIL and synergize with TRAIL action ultimately sensitizing the resistant and non-responsive cells. We summarize emerging strategies for enhanced TRAIL therapy in this review and cover a wide range of recent technologies that will provide impetus to rejuvenate the TRAIL therapeutics in the clinical realm.

Targeting non-apoptotic cell death in cancer treatment by nanomaterials: Recent advances and future outlook

Many tumors develop resistance to most of the apoptosis-based cancer therapies. In this sense targeting non-apoptotic forms of cell death including necroptosis, autophagy and ferroptosis may have therapeutic benefits in apoptosis-defective cancer cells. Nanomaterials have shown great advantages in cancer treatment owing to their unique characteristics. Besides, the capability of nanomaterials to induce different forms of cell death has gained widespread attention in cancer treatment. Reports in this field reflect the therapeutic potential of necroptotic cell death induced by nanomaterials in cancer. Also, autophagic cell death induced by nanomaterials alone and as a part of chemo-, radio- and photothermal therapy holds great promise as anticancer therapeutic option. Besides, ferroptosis induction by iron-based nanomaterials in drug delivery, immunotherapy, hyperthermia and imaging systems shows promising results in malignancies. Hence, this review is devoted to the latest efforts and the challenges in this field of research and its clinical merits.

Disturbed mitochondrial quality control involved in hepatocytotoxicity induced by silica nanoparticles

The extensive application of silica nanoparticles (SiNPs) brings about inevitable occupational, environmental, and even iatrogenic exposure for human beings. The liver, which is rich in mitochondria, is one of the target organs of SiNPs, but the underlying mechanisms by which these nanoparticles (NPs) interact with liver mitochondria and affect their functions still remain unclear. In the present study, we examined silicon nanoparticle (SiNP)-induced mitochondrial dysfunction, and further revealed its negative effects on mitochondrial quality control (MQC) in the human liver cell line L-02, including mitochondrial dynamics, mitophagy and biogenesis. Consequently, SiNPs induced cellular injury, accompanied by mitochondrial dysfunction, including mitochondrial reactive oxygen generation and mitochondrial membrane potential collapse. In line with the transmission electron microscopy (TEM)-observed abnormalities in the mitochondrial morphology and length distribution, a fission phenotype was manifested in the mitochondria of SiNP-exposed cells, and up-regulated DRP1 and FIS1, and down-regulated MFN1, were detected. Furthermore, the enhanced LC3II level, colocalization of the mitochondria and lysosomes, activated PINK1/Parkin signaling, and accumulated p62 in the SiNP-exposed cells suggested mitophagy disorder triggered by SiNPs. In addition, SiNPs inhibited mito-biogenesis, as evidenced by the reduced mitochondrial mass and mtDNA copy number, as well as the suppressed PGC1α-NRF1-TFAM signaling pathway. Overall, the study demonstrates that SiNPs trigger hepatocytotoxicity through interfering with the MQC process, bringing in excessive mitochondrial fission, mitophagy disorder and suppressed mito-biogenesis, leading to mitochondrial dysfunction and ensuing cell damage, and ultimately contributing to the occurrence and development of liver diseases. Our research could provide important experimental evidence related to safety assessments of SiNPs, especially in the field of biomedical applications.

Nanomedicine in Non-Small Cell Lung Cancer: From Conventional Treatments to Immunotherapy

Non-small cell lung cancer (NSCLC) remains the most common cause of cancer-related mortality. The heterogeneous nature of this disease hinders its diagnosis and treatment, requiring continuous advances in research aiming to understand its intricate nature. Consequently, the retrospective analysis of conventional therapies has allowed the introduction of novel tools provided by nanotechnology, leading to considerable improvements in clinical outcomes. Furthermore, the development of novel immunotherapies based on the recently understood interaction of the immune system with the tumor highlights the real possibility of definitively treating NSCLC from its early stages. Novel engineering approaches in nanomedicine will enable to overcome the intrinsic limits of conventional and emerging therapies regarding off-site cytotoxicity, specificity, resistance mechanisms, and administration issues. The convergence point of these therapies with nanotechnology lays the foundation for achieving currently unmet needs.

An eco-friendly synthesis of Enterococcus sp.-mediated gold nanoparticle induces cytotoxicity in human colorectal cancer cells

Gold nanoparticles (AuNPs) have become frequently used materials in biotechnological and biomedical applications including cancer. They can be commonly synthesized by biological and chemical methods. In the present study, we synthesized Enterococcus-mediated AuNPs and evaluated their cytotoxicity in human colorectal cancer cell line (HT-29). AuNPs are synthesized intracellularly using Enterococcus sp. RMAA. Characterization of AuNPs has done using UV spectrophotometry and transmission electron microscope. Cytotoxicity was evaluated by MTT assay. Intercellular reactive oxygen species (ROS) expression and apoptosis-related morphology were evaluated by dichlorodihydrofluorescein diacetate and acridine orange/ethidium bromide staining via fluorescence microscopy. JC-1 staining and caspase 3 immunofluorescence expression were analyzed by confocal microscopy. Enterococcus sp. RMAA-mediated AuNPs are spherical and induced concentration-dependent cytotoxicity in HT-29 cells. AuNP treatments also induced ROS and caspase-3 expressions and reduced the mitochondrial membrane potential. Morphology related to apoptotic changes was also noticed after AuNP treatments in HT-29 cells. The present study revealed that Enterococcus-derived AuNPs induced apoptotic cell death in HT-29 cells and suggests that AuNPs could be used as a pro apoptotic agent for colon cancer treatment.

TRAIL in oncology: From recombinant TRAIL to nano- and self-targeted TRAIL-based therapies

TNF-related apoptosis-inducing ligand (TRAIL) selectively induces the apoptosis pathway in tumor cells leading to tumor cell death. Because TRAIL induction can kill tumor cells, cancer researchers have developed many agents to target TRAIL and some of these agents have entered clinical trials in oncology. Unfortunately, these trials have failed for many reasons, including drug resistance, off-target toxicities, short half-life, and specifically in gene therapy due to the limited uptake of TRAIL genes by cancer cells. To address these drawbacks, translational researchers have utilized drug delivery platforms. Although, these platforms can improve TRAIL-based therapies, they are unable to sufficiently translate the full potential of TRAIL-targeting to clinically viable products. Herein, we first summarize the complex biology of TRAIL signaling, including TRAILs cross-talk with other signaling pathways and immune cells. Next, we focus on known resistant mechanisms to TRAIL-based therapies. Then, we discuss how nano-formulation has the potential to enhance the therapeutic efficacy of TRAIL protein. Finally, we specify strategies with the potential to overcome the challenges that cannot be addressed via nanotechnology alone, including the alternative methods of TRAIL-expressing circulating cells, tumor-targeting bacteria, viruses, and exosomes.

Autophagy Modulated by Inorganic Nanomaterials

With the rapid development of nanotechnology, inorganic nanomaterials (NMs) have been widely applied in modern society. As human exposure to inorganic NMs is inevitable, comprehensive assessment of the safety of inorganic NMs is required. It is well known that autophagy plays dual roles in cell survival and cell death. Moreover, inorganic NMs have been proven to induce autophagy perturbation in cells. Therefore, an in-depth understanding of inorganic NMs-modulated autophagy is required for the safety assessment of inorganic NMs. This review presents an overview of a set of inorganic NMs, consisting of iron oxide NMs, silver NMs, gold NMs, carbon-based NMs, silica NMs, quantum dots, rare earth oxide NMs, zinc oxide NMs, alumina NMs, and titanium dioxide NMs, as well as how each modulates autophagy. This review emphasizes the potential mechanisms underlying NMs-induced autophagy perturbation, as well as the role of autophagy perturbation in cell fate determination. Furthermore, we also briefly review the potential roles of inorganic NMs-modulated autophagy in diagnosis and treatment of disease.

Silver nanoparticles modulate mitochondrial dynamics and biogenesis in HepG2 cells

Silver nanoparticles (AgNPs) are inevitably released into the environment owing to their widespread applications in industry and medicine. The potential of their toxicity has aroused a great concern. Previous studies have shown that AgNPs exposure in HepG2 cells is primarily related to the damage of mitochondria, which includes induction of mitochondrial swelling and increase of intracellular levels of reactive oxygen species (ROS), the collapse of mitochondrial membrane potential and induction of apoptosis through a mitochondrial pathway. In this study, the effects of AgNPs exposure in HepG2 cells on mitochondrial dynamics and biogenesis were investigated. AgNPs were found to induce mitochondrial morphological and structural alterations. The expressions of key proteins (Drp1, Fis1, OPA1, Mff, Mfn1, and Mfn2) related to mitochondrial fission/fusion event were changed. Especially the expression of fission-related protein 1 (p-Drp1) (Ser616) was significantly up-regulated, whereas the expression of mitochondrial biogenesis protein (PGC-1α) was reduced in AgNP-treated cells. Concomitantly, the expression of autophagy marker proteins (LC3B and p62) was increased. The results suggested that AgNPs could trigger cytotoxicity by targeting the mitochondria, resulting in the disruption of mitochondrial function, damage to the mitochondrial structure and morphology, interfering in mitochondrial dynamics and biogenesis. The mitochondria could be a critical target of AgNPs in cells. The functions of mitochondria could be used for assessing the cytotoxic effects associated with AgNPs in cells.

Radiosensitizing Effect of Gadolinium Oxide Nanocrystals in NSCLC Cells Under Carbon Ion Irradiation

Gadolinium-based nanomaterials can not only serve as contrast agents but also contribute to sensitization in the radiotherapy of cancers. Among radiotherapies, carbon ion irradiation is considered one of the superior approaches with unique physical and biological advantages. However, only a few metallic nanoparticles have been used to improve carbon ion irradiation. In this study, gadolinium oxide nanocrystals (GONs) were synthesized using a polyol method to decipher the radiosensitizing mechanisms in non-small cell lung cancer (NSCLC) cell lines irradiated by carbon ions. The sensitizer enhancement ratio at the 10% survival level was correlated with the concentration of Gd in NSCLC cells. GONs elicited an increase in hydroxyl radical production in a concentration-dependent manner, and the yield of reactive oxygen species increased obviously in irradiated cells, which led to DNA damage and cell cycle arrest. Apoptosis and cytostatic autophagy were also significantly induced by GONs under carbon ion irradiation. The GONs may serve as an effective theranostic material in carbon ion radiotherapy for NSCLC.