Exploration of Zinc Oxide Nanoparticles as a Multitarget and Multifunctional Anticancer Nanomedicine

Nanotherapeutic strategies exploiting biological traits of cancer stem cells

Cancer stem cells (CSCs) represent a distinct subpopulation of cancer cells that orchestrate cancer initiation, progression, metastasis, and therapeutic resistance. Despite advances in conventional therapies, the persistence of CSCs remains a major obstacle to achieving cancer eradication. Nanomedicine-based approaches have emerged for precise CSC targeting and elimination, offering unique advantages in overcoming the limitations of traditional treatments. This review systematically analyzes recent developments in nanomedicine for CSC-targeted therapy, emphasizing innovative nanomaterial designs addressing CSC-specific challenges. We first provide a detailed examination of CSC biology, focusing on their surface markers, signaling networks, microenvironmental interactions, and metabolic signatures. On this basis, we critically evaluate cutting-edge nanomaterial engineering designed to exploit these CSC traits, including stimuli-responsive nanodrugs, nanocarriers for drug delivery, and multifunctional nanoplatforms capable of generating localized hyperthermia or reactive oxygen species. These sophisticated nanotherapeutic approaches enhance selectivity and efficacy in CSC elimination, potentially circumventing drug resistance and cancer recurrence. Finally, we present an in-depth analysis of current challenges in translating nanomedicine-based CSC-targeted therapies from bench to bedside, offering critical insights into future research directions and clinical implementation. This review aims to provide a comprehensive framework for understanding the intersection of nanomedicine and CSC biology, contributing to more effective cancer treatment modalities.

Nanoarchitecting intelligently encapsulated designs for improved cancer therapy

Despite the success in exploring various aspects of origination and therapeutic strategies, cancer has remained one of the most dreadful metabolic disorders due to failure to eradicate tumors comprehensively and frequent recurrence because of acquired resistance to the drugs. Recently, several advancements have been evidenced in the fabrication of various smart nanocarriers encapsulated with multiple components. Several reasons for smart nanoencapsulation include the enhancement of the bioavailability of drugs, precise targetability to reduce adverse effects on normal cells, and the ability to enable controlled drug release rates at the tumor sites. In addition, these smart nanocarriers protect encapsulated therapeutic cargo from deactivation, responsively delivering it based on the physiological or pathological characteristics of tumors. In this review, we present various smart approaches for cancer therapy, including organic materials, inorganic components, and their composites, as well as biomembrane-based nanoencapsulation strategies. These nanoencapsulation strategies, along with practical applications and their potential in cancer treatment, are discussed in depth, highlighting advantages and disadvantages, as well as aiming to reveal the ultimate prospects of nanoencapsulation in enhancing drug delivery efficiency and targeted cancer therapy.

Iron Oxide Nanoparticles Induce Macrophage Secretion of ATP and HMGB1 to Enhance Irradiation-Led Immunogenic Cell Death

ATP (adenosine triphosphate) and HMGB1 (high mobility group box 1 protein) are key players in treatments that induce immunogenic cell death (ICD). However, conventional therapies, including radiotherapy, are often insufficient to induce ICD. In this study, we explore a strategy using nanoparticle-loaded macrophages as a source of ATP and HMGB1 to complement radiation-induced intrinsic and adaptive immune responses. To this end, we tested three inorganic particles, namely, iron oxide nanoparticles (ION), aluminum oxide nanoparticles (AON), and zinc oxide nanoparticles (ZON), in vitro with bone marrow-derived dendritic cells (BMDCs) and then in vivo in syngeneic tumor models. Our results showed that ION was the most effective of the three nanoparticles in promoting the secretion of ATP and HMGB1 from macrophages without negatively affecting macrophage survival. Secretions from ION-loaded macrophages can activate BMDCs. Intratumoral injection of ION-loaded macrophages significantly enhanced tumor infiltration and activation of dendritic cells and cytotoxic T cells. Moreover, exogenous ION macrophages can enhance the efficacy of radiotherapy. In addition, direct injection of ION can also enhance the efficacy of radiotherapy, which is attributed to ION uptake by and stimulation of endogenous macrophages. Instead of directly targeting cancer cells, our strategy targets macrophages and uses them as a secretory source of ATP and HMGB1 to enhance radiation-induced ICD. Our research introduces a new nanoparticle-based immunomodulatory approach that may have applications in radiotherapy and beyond.

Facile control of giant green-emission in multifunctional ZnO quantum dots produced in a single-step process: femtosecond pulse ablation

Controlling both UV and visible emissions in ZnO quantum dots (QDs) poses a significant challenge due to the inherent introduction of defects during the growth process. We have refined the photoluminescence (PL) emission characteristics of ZnO QDs through a single-step, reagent-free femtosecond pulsed laser ablation in liquid (fs-PLAL) technique. The ratio of the near band edge (NBE) to deep-level emission (DLE), which determines the shape of the QDs' optical emission spectrum, is precisely controlled by the ablation laser pulse parameters-namely, pulse energy and temporal duration. Having established our ability to control the optical properties, we have investigated the mechanisms and physics involved in controlling optical emission. The key highlight of the work is that ablation with a fs-pulse induces substantial defect states without altering the particle size, with the extent of the effect being dependent on the pulse energy and pulse duration. The spectroscopic techniques inducing Raman spectroscopy, excitation power dependent PL and transient PL study provided deep insight into the PL emission properties of these similarly sized QDs. The improved DLE in these laser-ablated QDs is explained by a surface-recombination-layer approximation process employing steady-state and transient PL. Moreover, we have demonstrated the applicability of green emission for pH sensing within a linear range of 7-10 and highlight the inherent antibacterial properties of these QDs.

Green synthesized Zingiber officinale-ZnO nanoparticles: anticancer efficacy against 3D breast cancer model

Aim: ZnO NPs were prepared via green synthesis utilizing Zingiber Officinale.Methodology: Physical characterization and biological activity were performed against 2D, and 3D spheroids MCF-7 cell lines.Results: The NPs exhibited 188.9, 175.7 and 171.2 nm size with charge of -8.2, -11.7 and -9.7 mV for the 2%, 3% and 4% formulations. XRD confirmed a wurtzite hexagonal phase. FTIR spectra showed Zn-O stretching vibrations. The 2%, 3% and 4% formulations presented IC50 values of 14.7, 26.2 and 47 μg/ml, respectively, with complete destruction of MCF-7 spheroids. Elevated TNF-α levels suggested an inflammatory-mediated mechanism of action.Conclusion: 2% Zingiber officinale-derived ZnO NPs showed antitumor potential against deserving further mechanistic and in vivo explorations.

ρ-Coumaric acid-zinc oxide nanoparticles improve post-thaw quality of goat spermatozoa and developmental competence of fertilized oocytes in vitro

Excessive production of reactive oxygen species (ROS) during cryopreservation and post-thawing affects sperm quality and subsequent fertilizing capacity. Nanoparticles (NPs) with antioxidative properties can improve sperm function and male fertility. The aim of this study was to assess the effect of 100 µM ρ-coumaric acid (ρ-CA), 0.1 µM ρ-CA-NPs (PCNPs), 150 µg/mL zinc chloride (ZnCl2), 1 µg/mL zinc oxide-NPs (ZnO-NPs), ρ-CA + ZnCl2, PCNPs + ZnO-NPs, 0.001 µM of ρ-CA loaded on ZnO-NPs (ρ-CA-ZnONPs) on goat sperm parameters and fertilizing ability after cryopreservation. Semen samples from five Saanen goats were used. Various concentrations of treatments were incubated to determine the optimal concentrations for assessing sperm motility and viability. Subsequently, samples were filled with 0.5-mL straws, frozen, and stored in liquid nitrogen (- 196 °C). Evaluations of post-thaw spermatozoa parameters and fertilizing ability were performed. Addition of ρ-CA-ZnONPs and PCNPs + ZnO-NPs significantly increased sperm viability, motility, plasma membrane integrity, blastocyst rate, and blastocyst quality compared with the other treatments. Moreover, using ρ-CA-ZnONPs significantly decreased lipid peroxidation and DNA damage compared with the other treatments. In conclusion, spermatozoa are cryotolerant, resistant to post-thaw conditions, and have fertilizing ability that can be increased by adding ρ-CA-ZnONPs as an antioxidant to goat semen extenders.

pH and Pectinase Dual-Responsive Zinc Oxide Core-Shell Nanopesticide: Efficient Control of Sclerotinia Disease and Reduction of Environmental Risks

Sclerotinia sclerotiorum is one of the fungi that cause plant diseases. It damages plants by secreting large amounts of oxalic acid and cell wall-degrading enzymes. To meet this challenge, we designed a new pH/enzyme dual-responsive nanopesticide Pro@ZnO@Pectin (PZP). This nanopesticide uses zinc oxide (ZnO) as a carrier of prochloraz (Pro) and is encapsulated with pectin. When encountering oxalic acid released by Sclerotinia sclerotiorum, the acidic environment promotes the decomposition of ZnO; at the same time, the pectinase produced by Sclerotinia sclerotiorum can also decompose the outer pectin layer of PZP, thereby promoting the effective release of the active ingredient. Experimental data showed that PZP was able to achieve an efficient release rate of 57.25% and 68.46% when pectinase was added or under acidic conditions, respectively. In addition, in vitro tests showed that the antifungal effect of PZP was comparable to that of the commercial Pro (Pro SC) on the market, and its efficacy was 1.40 times and 1.32 times that of the Pro original drug (Pro TC), respectively. Crucially, the application of PZP significantly alleviated the detrimental impacts of Pro on wheat development. Soil wetting experiments have proved that PZP primarily remained in the soil, thereby decreasing its likelihood of contaminating water sources and reducing potential risks to non-target organisms. Moreover, PZP improved the foliar wettability of Pro, lowering the contact angle to 75.06°. Residue analyses indicated that PZP did not elevate prochloraz residue levels in tomato fruits compared to conventional applications, indicating that the nanopesticide formulation does not lead to excessive pesticide buildup. In summary, the nanopesticide PZP shows great promise for effectively managing Sclerotinia sclerotiorum while minimizing environmental impact.

Targeting the tumor microenvironment with biomaterials for enhanced immunotherapeutic efficacy

The tumor microenvironment (TME) is a complex system characterized by low oxygen, low pH, high pressure, and numerous growth factors and protein hydrolases that regulate a wide range of biological behaviors in the tumor and have a profound impact on cancer progression. Immunotherapy is an innovative approach to cancer treatment that activates the immune system, resulting in the spontaneous killing of tumor cells. However, the therapeutic efficacy of these clinically approved cancer immunotherapies (e.g., immune checkpoint blocker (ICB) therapies and chimeric antigen receptor (CAR) T-cell therapies) is far from satisfactory due to the presence of immunosuppressive TMEs created in part by tumor hypoxia, acidity, high levels of reactive oxygen species (ROS), and a dense extracellular matrix (ECM). With continuous advances in materials science and drug-delivery technologies, biomaterials hold considerable potential for targeting the TME. This article reviews the advances in biomaterial-based targeting of the TME to advance our current understanding on the role of biomaterials in enhancing tumor immunity. In addition, the strategies for remodeling the TME offer enticing advantages; however, the represent a double-edged sword. In the process of reshaping the TME, the risk of tumor growth, infiltration, and distant metastasis may increase.

Oxidative stress modulating nanomaterials and their biochemical roles in nanomedicine

Many pathological conditions are predominantly associated with oxidative stress, arising from reactive oxygen species (ROS); therefore, the modulation of redox activities has been a key strategy to restore normal tissue functions. Current approaches involve establishing a favorable cellular redox environment through the administration of therapeutic drugs and redox-active nanomaterials (RANs). In particular, RANs not only provide a stable and reliable means of therapeutic delivery but also possess the capacity to finely tune various interconnected components, including radicals, enzymes, proteins, transcription factors, and metabolites. Here, we discuss the roles that engineered RANs play in a spectrum of pathological conditions, such as cancer, neurodegenerative diseases, infections, and inflammation. We visualize the dual functions of RANs as both generator and scavenger of ROS, emphasizing their profound impact on diverse cellular functions. The focus of this review is solely on inorganic redox-active nanomaterials (inorganic RANs). Additionally, we deliberate on the challenges associated with current RANs-based approaches and propose potential research directions for their future clinical translation.

Enhanced anticancer effect of lysozyme-functionalized metformin-loaded shellac nanoparticles on a 3D cell model: role of the nanoparticle and payload concentrations

Here we used a 3D human hepatic tumour cell culture model to assess the in vitro efficacy of "active" metformin-loaded nanoparticles (NPs) as anticancer therapeutics. The metformin nanocarrier design was repurposed from previous studies targeting bacterial and fungal biofilms with antimicrobials loaded in protease-coated nanoparticles. These active nanocarriers were constructed with shellac cores loaded with metformin as the anticancer agent and featured a surface coating of the cationic protease lysozyme. The lysozyme's role as a nanocarrier surface coating is to partially digest the extracellular matrix (ECM) of the 3D tumour cell culture which increases its porosity and the nanocarrier penetration. Hep-G2 hepatic 3D clusteroids were formed using a water-in-water (w/w) Pickering emulsion based on an aqueous two-phase system (ATPS). Our specific metformin nano-formulation, comprising 0.25 wt% lysozyme-coated, 0.4 wt% metformin-loaded, 0.2 wt% shellac NPs sterically stabilized with 0.25 wt% Poloxamer 407, demonstrated significantly enhanced anticancer efficiency on 3D hepatic tumour cell clusteroids. We examined the role of the lysozyme surface functionality of the metformin nanocarriers in their ability to kill both 2D and 3D hepatic tumour cell cultures. The anticancer efficiency at high metformin payloads was compared with that at a high concentration of nanocarriers with a lower metformin payload. It was discovered that the high metformin payload NPs were more efficient than the lower metformin payload NPs with a higher nanocarrier concentration. This study introduces a reliable in vitro model for potential targeting of solid tumours with smart nano-therapeutics, presenting a viable alternative to animal testing for evaluating anticancer nanotechnologies.

Advances in engineered nanosystems: immunomodulatory interactions for therapeutic applications

Advances in nanotechnology have led to significant progress in the design and fabrication of nanoparticles (NPs) with improved therapeutic properties. NPs have been explored for modulating the immune system, serving as carriers for drug delivery or vaccine adjuvants, or acting as therapeutics themselves against a wide range of deadly diseases. The combination of NPs with immune system-targeting moieties has facilitated the development of improved targeted immune therapies. Targeted delivery of therapeutic agents using NPs specifically to the disease-affected cells, distinguishing them from other host cells, offers the major advantage of concentrating the therapeutic effect and reducing systemic side effects. Furthermore, the properties of NPs, including size, shape, surface charge, and surface modifications, influence their interactions with the targeted biological components. This review aims to provide insights into these diverse emerging and innovative approaches that are being developed and utilized for modulating the immune system using NPs. We reviewed various types of NPs composed of different materials and their specific application for modulating the immune system. Furthermore, we focused on the mechanistic effects of these therapeutic NPs on primary immune components, including T cells, B cells, macrophages, dendritic cells, and complement systems. Additionally, a recent overview of clinically approved immunomodulatory nanomedicines and potential future perspectives, offering new paradigms of this field, is also highlighted.

Targeted pH-responsive delivery of rosmarinic acid via phenylboronic acid functionalized mesoporous silica nanoparticles for liver and lung cancer therapy

Currently, chemotherapy is one of the most practiced approaches for the treatment of cancers. However, existing chemotherapeutic drugs have poor aqueous solubility, poor selectivity, higher systematic toxicity, and poor target accumulation. In this study, we designed and synthesized a boronic acid/ester-based pH-responsive nano-valve that specifically targets the microenvironment in cancer cells. The nano-valve comprises phenylboronic acid-coated mesoporous silica nanoparticles (B-MSN) loaded with polyphenolic compound Rosmarinic acid (ROS-B-MSN). The nano-valve was further coated with lignin (LIG) to achieve our desired LIG-ROS-BMSN nano-valve for targeted chemotherapy against Hep-G2 and NCI-H460 cell lines. The structure and properties of NPs were characterized by Fourier-transformed infrared spectroscopy (FTIR), Scanning Electron Microscopy (SEM) in combination with EDX, and Dynamic light scattering (DLS). The outcomes revealed that the designed LIG-ROS-BMSN were in the nanorange (144.1 ± 0.70 nm), had negative Zeta potential (-15.7 ± 0.46 mV) and had a nearly spherical morphology. In vitro, drug release investigations showed a controlled pH-dependent release profile under mild acidic conditions that could enhance the targeted chemotherapeutic response against cancer in mild acidic environments. The obtained LIG-ROS-BMSN nano valve achieved significantly lower IC50 values of (1.70 ± 0.01 μg/mL and 3.25 ± 0.14 μg/mL) against Hep-G2 and NCI-H460 cell lines as compared to ROS alone, which was (14.0 ± 0.7 μg/mL and 29.10 ± 0.25 μg/mL), respectively. The cellular morphology before and after treatment was further confirmed via inverted microscopy. The outcomes of the current study imply that our designed LIG-ROS-BMSN nanovalve is a potential carrier for cancer chemotherapeutics.

pH-Sensitive doxorubicin delivery using zinc oxide nanoparticles as a rectified theranostic platform: in vitro anti-proliferative, apoptotic, cell cycle arrest and in vivo radio-distribution studies

Despite enormous advancements in its management, cancer is the world's primary cause of mortality. Therefore, tremendous strides were made to produce intelligent theranostics with mitigated side effects and improved specificity and efficiency. Thus, we developed a pH-sensitive theranostic platform composed of dextran immobilized zinc oxide nanoparticles, loaded with doxorubicin and radiolabeled with the technetium-99m radionuclide (99mTc-labelled DOX-loaded ZnO@dextran). The platform measured 11.5 nm in diameter with -12 mV zeta potential, 88% DOX loading efficiency and 98.5% radiolabeling efficiency. It showed DOX release in a pH-responsive manner, releasing 93.1% cumulatively at pH 5 but just 7% at pH 7.4. It showed improved intracellular uptake, which resulted in a high growth suppressive effect against MCF-7 cancer cells as compared to the free DOX. It boasted a 4 times lower IC50 than DOX, indicating its significant anti-proliferative potential (0.14 and 0.55 μg ml-1, respectively). The in vitro biological evaluation revealed that its molecular mode of anti-proliferative action included downregulating Cdk-2, which provoked G1/S cell cycle arrest, and upregulating both the intracellular ROS level and caspase-3, which induced apoptosis and necrosis. The in vivo experiments in Ehrlich-ascites carcinoma bearing mice demonstrated that DOX-loaded ZnO@dextran showed a considerable 4-fold increase in anti-tumor efficacy compared to DOX. Moreover, by utilizing the diagnostic radionuclide (99mTc), the radiolabeled platform (99mTc-labelled DOX-loaded ZnO@dextran) was in vivo monitored in tumor-bearing mice, revealing high tumor accumulation (14% ID g-1 at 1 h p.i.) and reduced uptake in non-target organs with a 17.5 T/NT ratio at 1 h p.i. Hence, 99mTc-labelled DOX-loaded ZnO@dextran could be recommended as a rectified tumor-targeted theranostic platform.

Cold to Hot: Tumor Immunotherapy by Promoting Vascular Normalization Based on PDGFB Nanocomposites

Immunotherapy is a promising cancer therapeutic strategy. However, the "cold" tumor immune microenvironment (TIME), characterized by insufficient immune cell infiltration and immunosuppressive status, limits the efficacy of immunotherapy. Tumor vascular abnormalities due to defective pericyte coverage are gradually recognized as a profound determinant in "cold" TIME establishment by hindering immune cell trafficking. Recently, several vascular normalization strategies by improving pericyte coverage have been reported, whereas have unsatisfactory efficacy and high rates of resistance. Herein, a combinatorial strategy to induce tumor vasculature-targeted pericyte recruitment and zinc ion-mediated immune activation with a platelet-derived growth factor B (PDGFB)-loaded, cyclo (Arg-Gly-Asp-D-Phe-Lys)-modified zeolitic imidazolate framework 8 (PDGFB@ZIF8-RGD) nanoplatform is proposed. PDGFB@ZIF8-RGD effectively induced tumor vascular normalization, which facilitated trafficking and infiltration of immune effector cells, including natural killer (NK) cells, M1-like macrophages and CD8+ T cells, into tumor microenvironment. Simultaneously, vascular normalization promoted the accumulation of zinc ions inside tumors to trigger effector cell immune activation and effector molecule production. The synergy between these two effects endowed PDGFB@ZIF8-RGD with superior capabilities in reprogramming the "cold" TIME to a "hot" TIME, thereby initiating robust antitumor immunity and suppressing tumor growth. This combinatorial strategy for improving immune effector cell infiltration and activation is a promising paradigm for solid tumor immunotherapy.

Cross-sectional observational study: Investigation of zinc concentration in white patients with cancer

OBJECTIVES

Numerous studies describe the role of zinc in the immune system and metabolism. Zinc may influence the pathogenesis and prognosis of cancer. The aim of this study to determine the prevalence of zinc deficiency in patients with cancer. The study's primary objective was to evaluate the frequency of zinc deficiency in White patients with cancer and characterize the clinical factors predisposing individuals to decreased zinc concentration. The study also aimed to estimate the dose of zinc supplementation that would prevent deficiency.

METHODS

Retrospective data for this cross-sectional study were analyzed from 300 consecutive white patients diagnosed with neoplastic disease and admitted to a major oncology hospital for treatment. Zinc plasma concentration, nutritional status, body composition, and medical history of ailments and dysphagia were recorded. Supplementation was introduced in patients with zinc deficiency according to the local protocol. Zinc plasma levels were collected at follow-up visits.

RESULTS

Zinc deficiency was diagnosed in 68% of the patients. Poor nutritional status was significantly associated with zinc deficiency (low body mass index, weight loss, low albumin level). Low lean body mass (P = 0.003) and adipose tissue (P = 0.045) correlated with zinc deficiency. Patients with zinc deficiency reported dysphagia more frequently than those with normal zinc levels (18 versus 8%; P = 0.03). Squamous cell carcinoma was significantly associated with zinc deficiency (P = 0.043). Oral zinc supplementation resulted in reaching laboratory norms for plasma concentration in only 27% of patients with zinc deficiency and was not dependent on lower (10-15 mg) or higher (25-30 mg) dosing (P > 0.05).

CONCLUSIONS

Zinc deficiency is common in cachectic, malnourished patients with cancer. Nutritional guidelines for these patients should include screening for micronutrient deficiencies. Further studies are needed to determine the role, dosage, duration, and form of nutritional supplementation recommended for specific cancer diagnoses.

Galactomannan polysaccharide as a biotemplate for the synthesis of zinc oxide nanoparticles with photocatalytic, antimicrobial and anticancer applications

Biotemplates provide a facile, rapid, and environmentally benign route for synthesizing various nanostructured materials. Herein, Locust Bean Gum (LBG), a galactomannan polysaccharide, has been used as a biotemplate for synthesizing ZnO nanoparticles (NPs) for the first time. The composition, structure, morphology, and bandgap of ZnO were investigated by Energy Dispersive X-ray Spectroscopy (EDX), X-Ray Photoelectron Spectroscopy (XPS), X-ray powder diffraction (XRD), Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM) and UV-vis spectroscopy. XRD data showed single-phase crystalline hexagonal NPs. FTIR spectra confirmed the presence of M-O bonding in the sample. At a concentration of 0.5 mg/mL the NPs can degrade Rhodamine B under sunlight, displaying excellent photocatalytic activity. These NPs exhibited antimicrobial activity in both Staphylococcus aureus and Bacillus subtilis. Significant cell death was observed at 500 μg/mL, 250 μg/mL, 125 μg/mL and 62.5 μg/mL of NP in breast cancer, ovarian cancer and lung cancer cell lines. Wound healing assay showed that the NPs significantly blocked the cell migration at a concentration as low as 62.5 μg/mL in all three cell lines. Further optimization of the nanostructure properties will make it a promising candidate in the field of nano-biotechnology and bioengineering owing to its wide range of potential applications.

Manipulating macrophage polarization with nanoparticles to control metastatic behavior in heterotypic breast cancer micro-tissues via exosome signaling

This study aimed to investigate the effects of nanoparticles on macrophage polarization and their subsequent influence on post-tumorigenic behavior. Initially, seven different nanoparticles were applied to macrophages, and Zn-Ni-FeO (100 nm) and palladium nanoparticles (PdNPs, ∼25 nm) were found to induce M1-polarization in macrophages. A co-culture experiment was then conducted to examine the effects of macrophages on MCF-7 breast cancer micro-tissues. The M2-macrophages promoted tumor proliferation, while M1- and PdNPs-induced macrophages showed anti-tumor effects by suppressing cell proliferation. To reveal the mechanisms of effect, exosomes isolated from M1 (M1-Exo), M0 (M0-Exo), M2 (M2-Exo), and PdNPs-induced (PdNPs-Exo) macrophages were applied to the heterotypic tumor micro-tissues including MCF-7, human umbilical vein endothelial cells (HUVECs), and primary human dermal fibroblasts (phDFs). M2-Exo was seen to promote the migration of cancer cells and induce epithelial-mesenchymal transition (EMT), while M1-Exo suppressed these behaviors. PdNPs-Exo was effective in suppressing the aggressive nature of breast cancer cells similar to M1-Exo, moreover, the efficacy of 5-fluorouracil (5-FU) was increased in combination with PdNPs-Exo in both MCF-7 and heterotypic micro-tissues. In conclusion, PdNPs-Exo has potential anti-tumor effects, can be used as a combination therapy to enhance the efficacy of anti-cancer drugs, as well as innovative implants for breast cancer treatment.

Exploring the antibacterial and dermatitis-mitigating properties of chicken egg white-synthesized zinc oxide nano whiskers

Introduction

Zinc oxide nanoparticles (ZnO-NPs) have garnered considerable interest in biomedical research primarily owing to their prospective therapeutic implications in combatting pathogenic diseases and microbial infections. The primary objective of this study was to examine the biosynthesis of zinc oxide nanowhiskers (ZnO-NWs) using chicken egg white (albumin) as a bio-template. Furthermore, this study aimed to explore the potential biomedical applications of ZnO NWs in the context of infectious diseases.

Methods

The NWs synthesized through biological processes were observed using electron microscopy, which allowed for detailed examination of their characteristics. The results of these investigations indicated that the NWs exhibited a size distribution ranging from approximately 10 to 100 nm. Fourier-transform infrared spectroscopy (FTIR) and scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDX) mapping analyses successfully corroborated the size, dimensions, and presence of biological constituents during their formation. In this study, XTT assay and confocal imaging were employed to provide evidence of the efficacy of ZnO-NWs in the eradication of bacterial biofilms. The target bacterial strains were Staphylococcus aureus and Escherichia coli. Furthermore, we sought to address pertinent concerns regarding the biocompatibility of the ZnO-NWs. This was achieved through comprehensive evaluation of the absence of cytotoxicity in normal HEK-293T and erythrocytes.

Results

The findings of this investigation unequivocally confirmed the biocompatibility of the ZnO-NWs. The biosynthesized ZnO-NWs demonstrated a noteworthy capacity to mitigate the dermatitis-induced consequences induced by Staphylococcus aureus in murine models after a therapeutic intervention lasting for one week.

Discussion

This study presents a comprehensive examination of the biosynthesis of zinc oxide nanowhiskers (ZnO-NWs) derived from chicken egg whites. These findings highlight the considerable potential of biosynthesized ZnO-NWs as a viable option for the development of therapeutic agents targeting infectious diseases. The antibacterial efficacy of ZnO-NWs against both susceptible and antibiotic-resistant bacterial strains, as well as their ability to eradicate biofilms, suggests their promising role in combating infectious diseases. Furthermore, the confirmed biocompatibility of ZnO-NWs opens avenues for their safe use in biomedical applications. Overall, this research underscores the therapeutic promise of ZnO-NWs and their potential significance in future biomedical advancements.

Multifunctional role of zinc in human health: an update

Zinc is a multipurpose trace element for the human body, as it plays a crucial part in various physiological processes, such as cell growth and development, metabolism, cognitive, reproductive, and immune system function. Its significance in human health is widely acknowledged, and this has led the scientific community towards more research that aims to uncover all of its beneficial properties, especially when compared to other essential metal ions. One notable area where zinc has shown beneficial effects is in the prevention and treatment of various diseases, including cancer. This review aims to explain the involvement of zinc in specific health conditions such as cancer, coronavirus disease 2019 (COVID-19) and neurological disorders like Alzheimer's disease, as well as its impact on the gut microbiome.

Metal-Based Nanoparticles for Cancer Metalloimmunotherapy

Although the promise of cancer immunotherapy has been partially fulfilled with the unprecedented clinical success of several immunotherapeutic interventions, some issues, such as limited response rate and immunotoxicity, still remain. Metalloimmunotherapy offers a new form of cancer immunotherapy that utilizes the inherent immunomodulatory features of metal ions to enhance anticancer immune responses. Their versatile functionalities for a multitude of direct and indirect anticancer activities together with their inherent biocompatibility suggest that metal ions can help overcome the current issues associated with cancer immunotherapy. However, metal ions exhibit poor drug-like properties due to their intrinsic physicochemical profiles that impede in vivo pharmacological performance, thus necessitating an effective pharmaceutical formulation strategy to improve their in vivo behavior. Metal-based nanoparticles provide a promising platform technology for reshaping metal ions into more drug-like formulations with nano-enabled engineering approaches. This review provides a general overview of cancer immunotherapy, the immune system and how it works against cancer cells, and the role of metal ions in the host response and immune modulation, as well as the impact of metal ions on the process via the regulation of immune cells. The preclinical studies that have demonstrated the potential of metal-based nanoparticles for cancer metalloimmunotherapy are presented for the representative nanoparticles constructed with manganese, zinc, iron, copper, calcium, and sodium ions. Lastly, the perspectives and future directions of metal-based nanoparticles are discussed, particularly with respect to their clinical applications.

Emerging biomaterials for tumor immunotherapy

BACKGROUND

The immune system interacts with cancer cells in various intricate ways that can protect the individual from overproliferation of cancer cells; however, these interactions can also lead to malignancy. There has been a dramatic increase in the application of cancer immunotherapy in the last decade. However, low immunogenicity, poor specificity, weak presentation efficiency, and off-target side effects still limit its widespread application. Fortunately, advanced biomaterials effectively contribute immunotherapy and play an important role in cancer treatment, making it a research hotspot in the biomedical field.

MAIN BODY

This review discusses immunotherapies and the development of related biomaterials for application in the field. The review first summarizes the various types of tumor immunotherapy applicable in clinical practice as well as their underlying mechanisms. Further, it focuses on the types of biomaterials applied in immunotherapy and related research on metal nanomaterials, silicon nanoparticles, carbon nanotubes, polymer nanoparticles, and cell membrane nanocarriers. Moreover, we introduce the preparation and processing technologies of these biomaterials (liposomes, microspheres, microneedles, and hydrogels) and summarize their mechanisms when applied to tumor immunotherapy. Finally, we discuss future advancements and shortcomings related to the application of biomaterials in tumor immunotherapy.

CONCLUSION

Research on biomaterial-based tumor immunotherapy is booming; however, several challenges remain to be overcome to transition from experimental research to clinical application. Biomaterials have been optimized continuously and nanotechnology has achieved continuous progression, ensuring the development of more efficient biomaterials, thereby providing a platform and opportunity for breakthroughs in tumor immunotherapy.

Emerging Advancements in Piezoelectric Nanomaterials for Dynamic Tumor Therapy

Cancer is one of the deadliest diseases, having spurred researchers to explore effective therapeutic strategies for several centuries. Although efficacious, conventional chemotherapy usually introduces various side effects, such as cytotoxicity or multi−drug resistance. In recent decades, nanomaterials, possessing unique physical and chemical properties, have been used for the treatment of a wide range of cancers. Dynamic therapies, which can kill target cells using reactive oxygen species (ROS), are promising for tumor treatment, as they overcome the drawbacks of chemotherapy methods. Piezoelectric nanomaterials, featuring a unique property to convert ultrasound vibration energy into electrical energy, have also attracted increasing attention in biomedical research, as the piezoelectric effect can drive chemical reactions to generate ROS, leading to the newly emerging technique of ultrasound−driven tumor therapy. Piezoelectric materials are expected to bring a better solution for efficient and safe cancer treatment, as well as patient pain relief. In this review article, we highlight the most recent achievements of piezoelectric biomaterials for tumor therapy, including the mechanism of piezoelectric catalysis, conventional piezoelectric materials, modified piezoelectric materials and multifunctional piezoelectric materials for tumor treatment.

Fluorescence Properties of ZnOQDs-GO-g-C3N4 Nanocomposites

In this paper, the fluorescence properties of ZnOQD-GO-g-C3N4 composite materials (ZCGQDs) were studied. Firstly, the addition of a silane coupling agent (APTES) in the synthesis process was explored, and it was found that the addition of 0.04 g·mL-1 APTES had the largest relative fluorescence intensity and the highest quenching efficiency. The selectivity of ZCGQDs for metal ions was also investigated, and it was found that ZCGQDs showed good selectivity for Cu2+. ZCGQDs were optimally mixed with Cu2+ for 15 min. ZCGQDs also had good anti-interference capability toward Cu2+. There was a linear relationship between the concentration of Cu2+ and the fluorescence intensity of ZCGQDs in the range of 1~100 µM. The regression equation was found to be F0/F = 0.9687 + 0.12343C. The detection limit of Cu2+ was about 1.74 μM. The quenching mechanism was also analyzed.

Nanocarriers overcoming biological barriers induced by multidrug resistance of chemotherapeutics in 2D and 3D cancer models

Multidrug resistance (MDR) is currently a big challenge in cancer therapy and limits its success in several patients. Tumors use the MDR mechanisms to colonize the host and reduce the efficacy of chemotherapeutics that are injected as single agents or combinations. MDR mechanisms are responsible for inactivation of drugs and formbiological barriers in cancer like the drug efflux pumps, aberrant extracellular matrix, hypoxic areas, altered cell death mechanisms, etc. Nanocarriers have some potential to overcome these barriers and improve the efficacy of chemotherapeutics. In fact, they are versatile and can deliver natural and synthetic biomolecules, as well as RNAi/DNAi, thus providing a controlled release of drugs and a synergistic effect in tumor tissues. Biocompatible and safe multifunctional biopolymers, with or without specific targeting molecules, modify the surface and interface properties of nanocarriers. These modifications affect the interaction of nanocarriers with cellular models as well as the selection of suitable models for in vitro experiments. MDR cancer cells, and particularly their 2D and 3D models, in combination with anatomical and physiological structures of tumor tissues, can boost the design and preparation of nanomedicines for anticancer therapy. 2D and 3D cancer cell cultures are suitable models to study the interaction, internalization, and efficacy of nanocarriers, the mechanisms of MDR in cancer cells and tissues, and they are used to tailor a personalized medicine and improve the efficacy of anticancer treatment in patients. The description of molecular mechanisms and physio-pathological pathways of these models further allow the design of nanomedicine that can efficiently overcome biological barriers involved in MDR and test the activity of nanocarriers in 2D and 3D models of MDR cancer cells.

Husk-like Zinc Oxide Nanoparticles Induce Apoptosis through ROS Generation in Epidermoid Carcinoma Cells: Effect of Incubation Period on Sol-Gel Synthesis and Anti-Cancerous Properties

This study effectively reports the influence of experimental incubation period on the sol-gel production of husk-like zinc oxide nanoparticles (ZNPs) and their anti-cancerous abilities. The surface morphology of ZNPs was studied with the help of SEM. With the use of TEM, the diameter range of the ZNPs was estimated to be ~86 and ~231 nm for ZNP^A and ZNP^B, prepared by incubating zinc oxide for 2 and 10 weeks, respectively. The X-ray diffraction (XRD) investigation showed that ZNPs had a pure wurtzite crystal structure. On prolonging the experimental incubation, a relative drop in aspect ratio was observed, displaying a distinct blue-shift in the UV-visible spectrum. Furthermore, RBC lysis assay results concluded that ZNP^A and ZNP^B both demonstrated innoxious nature. As indicated by MTT assay, reactive oxygen species (ROS) release, and chromatin condensation investigations against the human epidermoid carcinoma (HEC) A431 cells, ZNP^B demonstrated viable relevance to chemotherapy. Compared to ZNP^B, ZNP^A had a slightly lower IC₅₀ against A431 cells due to its small size. This study conclusively describes a simple, affordable method to produce ZNP nano-formulations that display significant cytotoxicity against the skin cancer cell line A431, suggesting that ZNPs may be useful in the treatment of cancer.

In Vitro Antimicrobial and Anticancer Peculiarities of Ytterbium and Cerium Co-Doped Zinc Oxide Nanoparticles

Zinc oxide nanoparticles (ZnO NPs) are a promising platform for their use in biomedical research, especially given their anticancer and antimicrobial activities. This work presents the synthesis of ZnO NPs doped with different amounts of rare-earth ions of ytterbium (Yb) and cerium (Ce) and the assessment of their anticancer and antimicrobial activities. The structural investigations indicated a hexagonal wurtzite structure for all prepared NPs. The particle size was reduced by raising the amount of Ce and Yb in ZnO. The anticancer capabilities of the samples were examined by the cell viability MTT assay. Post 48-h treatment showed a reduction in the cancer cell viability, which was x = 0.00 (68%), x = 0.01 (58.70%), x = 0.03 (80.94%) and x = 0.05 (64.91%), respectively. We found that samples doped with x = 0.01 and x = 0.05 of Yb and Ce showed a better inhibitory effect on HCT-116 cancer cells than unadded ZnO (x = 0.00). The IC50 for HCT-116 cells of Ce and Yb co-doped ZnO nanoparticles was calculated and the IC50 values were x = 0.01 (3.50 µg/mL), x = 0.05 (8.25 µg/mL), x = 0.00 (11.75 µg/mL), and x = 0.03 (21.50 µg/mL). The treatment-doped ZnO NPs caused apoptotic cell death in the HCT-116 cells. The nanoparticles showed inhibitory action on both C. albicans and E. coli. It can be concluded that doping ZnO NPs with Yb and Ce improves their apoptotic effects on cancer and microbial cells.

Inhibition of ABCC9 by zinc oxide nanoparticles induces ferroptosis and inhibits progression, attenuates doxorubicin resistance in breast cancer

Background

Zinc oxide nanoparticles (ZONs) are a type of nanomaterial that has presented anti-cancer properties in breast cancer (BC). However, the function of ABCC9 in BC and its correlation with ZONs are still elusive.

Methods

Here, we identified the crucial role of ABCC9 in modulating ferroptosis and doxorubicin (Dox) resistance in BC and the targeted function of ZONs to ABCC9.

Results

The silencing of ABCC9 significantly repressed the viability of BC cells. The knockdown of ABCC9 decreased the numbers of Edu-positive BC cells. Conversely, BC cell apoptosis was increased by the inhibition of ABCC9. Besides, the silencing of ABCC9 reduced the capability of migration and invasion of BC cells. Significantly, tumorigenicity analysis demonstrated that the tumor growth of BC cells was suppressed by the depletion of ABCC9 in the xenograft model of nude mice. Moreover, the treatment of ferroptosis activator erastin repressed cell viability of BC cells and ABCC9 overexpression rescued the repression. Similarly, the numbers of Edu-positive BC cells were inhibited by erastin and the overexpression of ABCC9 reversed the inhibitory effect of erastin. The levels of GSH were decreased and MDA, lipid ROS, and iron levels were increased by the treatment of erastin, while the ABCC9 overexpression could reverse these results in BC cells. Consistently, erastin suppressed the expression of ferroptosis inhibitory factors, including GPX4 and SLC7A11, in BC cells and the overexpression of ABCC9 rescued the expression. The IC50 value of Dox was reduced by the knockdown of ABCC9 in Dox-resistant BC cells (BC/Dox). The numbers of Edu-positive BC/Dox cells were attenuated by the depletion of ABCC9. Meanwhile, the apoptosis of BC/Dox cells was stimulated by the silencing of ABCC9. Furthermore, the treatment of ZONs attenuated Dox resistance of BC cells. ZONs remarkably repressed the expression of ABCC9 in BC/Dox cells. ZONs inhibited the cell viability of BC/Dox cells and the overexpression of ABCC9 reversed the repression. Moreover, the treatment of ZONs reduced GSH levels and enhanced MDA, lipid ROS, and iron levels in erastin-stimulated BC/Dox cells.

Conclusions

In conclusion, we discovered that the inhibition of ABCC9 by zinc oxide nanoparticles induces ferroptosis and attenuates Dox resistance in BC.

Bio-Activated PEEK: Promising Platforms for Improving Osteogenesis through Modulating Macrophage Polarization

The attention on orthopedic biomaterials has shifted from their direct osteogenic properties to their osteoimmunomodulation, especially the modulation of macrophage polarization. Presently, advanced technologies endow polyetheretherketone (PEEK) with good osteoimmunomodulation by modifying PEEK surface characteristics or incorporating bioactive substances with regulating macrophage polarization. Recent studies have demonstrated that the fabrication of a hydrophilic surface and the incorporation of bioactive substances into PEEK (e.g., zinc, calcium, and phosphate) are good strategies to promote osteogenesis by enhancing the polarization of M2 macrophages. Furthermore, the modification by other osteoimmunomodulatory composites (e.g., lncRNA-MM2P, IL-4, IL-10, and chitosan) and their controlled and desired release may make PEEK an optimal bio-activated implant for regulating and balancing the osteogenic system and immune system. The purpose of this review is to comprehensively evaluate the potential of bio-activated PEEK in polarizing macrophages into M2 phenotype to improve osteogenesis. For this objective, we retrieved and discussed different kinds of bio-activated PEEK regarding improving osteogenesis through modulating macrophage polarization. Meanwhile, the relevant challenges and outlook were presented. We hope that this review can shed light on the development of bio-activated PEEK with more favorable osteoimmunomodulation.

Leveraging Nanodrug Delivery System for Simultaneously Targeting Tumor Cells and M2 Tumor-Associated Macrophages for Efficient Colon Cancer Therapy

Tumor-associated macrophages (TAMs) widely exist in the solid tumors, which participate in the entire course of tumor development and execute momentous impacts. Therefore, manipulating TAMs has been identified as an expecting strategy with immense potential for cancer therapy. Herein, a nanodrug delivery system was leveraged for simultaneously targeting tumor cells and M2-type TAMs for efficient colon cancer therapy. The broad-spectrum anticancer chemotherapeutic drug doxorubicin (DOX) was hitchhiked in a mannose-modified bovine serum albumin (MAN-BSA) carrier. The DOX@MAN-BSA nanodrug delivery system was verified to possess feasible physical performances for unhindered systemic circulation and active targeting on colon tumors. DOX@MAN-BSA nanoparticles could be preferentially swallowed by colon tumor cells and M2 TAMs through mannose receptor-mediated endocytosis. Further in vivo antitumor therapy in CT26 colon tumor-bearing mice has achieved remarkable suppression efficacy with satisfactory biosafety. Leveraging the nanodrug delivery system for simultaneously targeting tumor cells and M2 TAMs has contributed a feasible strategy to collaboratively repress the malignant tumor cells and the collusive M2 TAMs for efficient cancer therapy.

Antitumor Activity of the Zinc Oxide Nanoparticles Coated with Low-Molecular-Weight Heparin and Doxorubicin Complex In Vitro and In Vivo

Various metal oxide nanomaterials have been widely used as carriers to prepare pH-sensitive nanomedicines to respond to the acidic tumor microenvironment promoting antitumor efficiency. Herein, we used zinc oxide nanoparticles (ZnO NPs) as metal oxide nanomaterial coated with low-molecular-weight heparin (LMHP) and doxorubicin (DOX) complex (LMHP-DOX) to prepare ZnO-LD NPs for controllable pH-triggered DOX release on the targeted site. Our results indicated that the released DOX from ZnO-LD NPs was pH-sensitive. The oxygen produced by ZnO-LD NPs in H₂O₂ solution was observed in in vitro experiment. The ZnO-LD NPs entered into both PC-3M and 4T1 tumor cells via clathrin-mediated endocytosis and micropinocytosis pathway. The intracellular reactive oxygen species (ROS) generated by ZnO-LD NPs could significantly increase the caspase 3/7 level, leading to tumor cell apoptosis. The in vitro and in vivo antitumor activity was confirmed in PC-3M and 4T1 cell lines or tumor-bearing mice models. The in vivo and in vitro tumor images via second-order nonlinearity of ZnO-LD NPs indicated that ZnO-LD NPs could penetrate deep into the tumor tissues. Therefore, the ZnO-LD NPs developed in our study could provide an efficient approach for the preparation of pH-sensitive nano delivery systems suitable for tumor therapy and imaging.

Chicken skin-derived collagen peptides chelated zinc promotes zinc absorption and represses tumor growth and invasion in vivo by suppressing autophagy

To improve the utilization value of chicken by-products, we utilized the method of step-by-step hydrolysis with bromelain and flavourzyme to prepare low molecular weight chicken skin collagen peptides (CCP) (<5 kDa) and characterized the amino acids composition of the CCP. Then, we prepared novel CCP-chelated zinc (CCP–Zn) by chelating the CCP with ZnSO₄. We found that the bioavailability of CCP–Zn is higher than ZnSO₄. Besides, CCP, ZnSO₄, or CCP–Zn effectively repressed the tumor growth, invasion, and migration in a Drosophila malignant tumor model. Moreover, the anti-tumor activity of CCP–Zn is higher than CCP or ZnSO₄. Furthermore, the functional mechanism studies indicated that CCP, ZnSO₄, or CCP–Zn inhibits tumor progression by reducing the autonomous and non-autonomous autophagy in tumor cells and the microenvironment. Therefore, this research provides in vivo evidence for utilizing chicken skin in the development of zinc supplements and cancer treatment in the future.

An Investigation for Skin Tissue Regeneration Enhancement/Augmentation by Curcumin-Loaded Self-Emulsifying Drug Delivery System (SEDDS)

Diabetes, one of the global metabolic disorders, is often associated with delayed wound healing due to the elevated level of free radicals at the wound site, which hampers skin regeneration. This study aimed at developing a curcumin-loaded self-emulsifying drug delivery system (SEDDS) for diabetic wound healing and skin tissue regeneration. For this purpose, various curcumin-loaded SEDDS formulations were prepared and optimized. Then, the SEDDS formulations were characterized by the emulsion droplet size, surface charge, drug content/entrapment efficiency, drug release, and stability. In vitro, the formulations were assessed for the cellular uptake, cytotoxicity, cell migration, and inhibition of the intracellular ROS production in the NIH3T3 fibroblasts. In vivo, the formulations' wound healing and skin regeneration potential were evaluated on the induced diabetic rats. The results indicated that, after being dispersed in the aqueous medium, the optimized SEDDS formulation was readily emulsified and formed a homogenous dispersion with a droplet size of 37.29 ± 3.47 nm, surface charge of -20.75 ± 0.07 mV, and PDI value of less than 0.3. The drug content in the optimized formulation was found to be 70.51% ± 2.31%, with an encapsulation efficiency of 87.36% ± 0.61%. The SEDDS showed a delayed drug release pattern compared to the pure drug solution, and the drug release rate followed the Fickian diffusion kinetically. In the cell culture, the formulations showed lower cytotoxicity, higher cellular uptake, and increased ROS production inhibition, and promoted the cell migration in the scratch assay compared to the pure drug. The in vivo data indicated that the curcumin-loaded SEDDS-treated diabetic rats had significantly faster-wound healing and re-epithelialization compared with the untreated and pure drug-treated groups. Our findings in this work suggest that the curcumin-loaded SEDDS might have great potential in facilitating diabetic wound healing and skin tissue regeneration.

Zinc carnosine: Frontiers advances of supplement for cancer therapy

Zinc (Zn) has an existence within large quantities in the human brain, while accumulating within synaptic vesicle. There is growing evidence that Zn metabolic equilibrium breaking participates into different diseases (e.g., vascular dementia, carcinoma, Alzheimer's disease). Carnosine refers to an endogenic dipeptide abundant in skeletal muscle and brains and exerts a variety of positive influences (e.g., carcinoma resistance, crosslinking resistance, metal chelation and oxidation limitation). A complex of Zn and carnosine, called Zinc-L-carnosine (ZnC), has been extensively employed within Zn supplement therapeutic method and the treating approach for ulcers. ZnC has been shown to play a variety of roles in the body, including inhibiting intracellular reactive oxygen species(ROS) and free radical levels, inhibiting inflammation, supplementing zinc enzymes and promoting wound healing and mucosal cell repair. The present study conducting a reviewing process for the advances of ZnC in tumor adjuvant therapy.

Macrophages Are a Double-Edged Sword: Molecular Crosstalk between Tumor-Associated Macrophages and Cancer Stem Cells

Cancer stem cells (CSCs) are a subset of highly tumorigenic cells in tumors. They have enhanced self-renewal properties, are usually chemo-radioresistant, and can promote tumor recurrence and metastasis. They can recruit macrophages into the tumor microenvironment and differentiate them into tumor-associated macrophages (TAMs). TAMs maintain CSC stemness and construct niches that are favorable for CSC survival. However, how CSCs and TAMs interact is not completely understood. An understanding on these mechanisms can provide additional targeting strategies for eliminating CSCs. In this review, we comprehensively summarize the reported mechanisms of crosstalk between CSCs and TAMs and update the related signaling pathways involved in tumor progression. In addition, we discuss potential therapies targeting CSC–TAM interaction, including targeting macrophage recruitment and polarization by CSCs and inhibiting the TAM-induced promotion of CSC stemness. This review also provides the perspective on the major challenge for developing potential therapeutic strategies to overcome CSC-TAM crosstalk.

Multifunctional Nanoplatforms as a Novel Effective Approach in Photodynamic Therapy and Chemotherapy, to Overcome Multidrug Resistance in Cancer

It is more than sixty years since the era of modern photodynamic therapy (PDT) for cancer began. Enhanced selectivity for malignant cells with a reduced selectivity for non-malignant cells and good biocompatibility along with the limited occurrence of side effects are considered to be the most significant advantages of PDT in comparison with conventional therapeutic approaches, e.g., chemotherapy. The phenomenon of multidrug resistance, which is associated with drug efflux transporters, was originally identified in relation to the application of chemotherapy. Unfortunately, over the last thirty years, numerous papers have shown that many photosensitizers are the substrates of efflux transporters, significantly restricting the effectiveness of PDT. The concept of a dynamic nanoplatform offers a possible solution to minimize the multidrug resistance effect in cells affected by PDT. Indeed, recent findings have shown that the utilization of nanoparticles could significantly enhance the therapeutic efficacy of PDT. Additionally, multifunctional nanoplatforms could induce the synergistic effect of combined treatment regimens, such as PDT with chemotherapy. Moreover, the surface modifications that are associated with nanoparticle functionalization significantly improve the target potential of PDT or chemo-PDT in multidrug resistant and cancer stem cells.

A mutually beneficial macrophages-mediated delivery system realizing photo/immune therapy

The accumulation of nanomedicines in tumor tissues determines their therapeutic efficacy. We herein exploit the tropism of macrophages to improve the accumulation and retention time of nanomedicine at tumors. Interestingly, macrophages are not merely as transporters, but killers activated by nanomedicine. The system(M@C-HA/ICG) was established by decorating macrophages with hyaluronic acid-modified hollow mesoporous carbon (C) nanoparticles loading indocyanine green (ICG). Notably, C nanoparticles with superior photothermal conversion capability not merely guarantee the efficient delivery of ICG through high drug loading efficiency and inhibiting the premature leaky, but effectually activate the polarization of macrophages. The results exhibited that those activated macrophages could release pro-inflammatory cytokines (NO, TNF-α, IL-12), while M@C-HA/ICG afforded about 2-fold higher tumor accumulation compared with pure nanoparticle C-HA/ICG and produced heat and singlet oxygen (¹O₂) under irradiation of an 808 nm laser, realizing the combination of photodynamic therapy (PDT), photothermal therapy (PTT) and cytokines-mediated immunotherapy. Specially, we also investigated the relationship of singlet oxygen (¹O₂) or temperature and tumor-killing activity for understanding the specific effectual procedure of PDT/PTT synergistic therapy. Overall, we firstly established an "all active" delivery system integrating the features of nanomedicine with biological functions of macrophages, providing a novel insight for cell-mediated delivery platform and tumor targeted multimodality anti-cancer therapy.

Recent advances in ZnO-based photosensitizers: Synthesis, modification, and applications in photodynamic cancer therapy

Zinc oxide nanoparticles (ZnO NPs) are important semiconductor materials with interesting photo-responsive properties. During the past, ZnO-based NPs have received considerable attention for photodynamic therapy (PDT) due to their biocompatibility and excellent potential of generating tumor-killing reactive oxygen species (ROS) through gentle photodynamic activation. This article provides a comprehensive review of the recent developments and improvements in optical properties of ZnO NPs as photosensitizers for PDT. The optical properties of ZnO-based photosensitizers are significantly dependent on their charge separation, absorption potential, band gap engineering, and surface area, which can be adjusted/tuned by doping, compositing, and morphology control. Here, we first summarize the recent progress in the charge separation capability, absorption potential, band gap engineering, and surface area of nanosized ZnO-based photosensitizers. Then, morphology control that is closely related to their synthesis method is discussed. Following on, the state-of-art for the ZnO-based NPs in the treatment of hypoxic tumors is comprehensively reviewed. Finally, we provide some outlooks on common targeted therapy methods for more effective tumor killing, including the attachment of small molecules, antibodies, ligands molecules, and receptors to NPs which further improve their selective distribution and targeting, hence improving the therapeutic effectiveness. The current review may provide useful guidance for the researchers who are interested in this promising dynamic cancer treatment technology.

Synthesis, Characterization, and Assessment of Anti-Cancer Potential of ZnO Nanoparticles in an In Vitro Model of Breast Cancer

Advanced innovations for combating variants of aggressive breast cancer and overcoming drug resistance are desired. In cancer treatment, ZnO nanoparticles (NPs) have the capacity to specifically and compellingly activate apoptosis of cancer cells. There is also a pressing need to develop innovative anti-cancer therapeutics, and recent research suggests that ZnO nanoparticles hold great potential. Here, the in vitro chemical effectiveness of ZnO NPs has been tested. Zinc oxide (ZnO) nanoparticles were synthesized using Citrullus colocynthis (L.) Schrad by green methods approach. The generated ZnO was observed to have a hexagonal wurtzite crystal arrangement. The generated nanomaterials were characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM), UV-visible spectroscopy. The crystallinity of ZnO was reported to be in the range 50-60 nm. The NPs morphology showed a strong absorbance at 374 nm with an estimated gap band of 3.20 eV to 3.32 eV. Microscopy analysis proved the morphology and distribution of the generated nanoparticles to be around 50 nm, with the elemental studies showing the elemental composition of ZnO and further confirming the purity of ZnO NPs. The cytotoxic effect of ZnO NPs was evaluated against wild-type and doxorubicin-resistant MCF-7 and MDA-MB-231 breast cancer cell lines. The results showed the ability of ZnO NPs to inhibit the prefoliation of MCF-7 and MDA-MB-231 prefoliation through the induction of apoptosis without significant differences in both wild-type and resistance to doxorubicin.

Anticancer properties of novel zinc oxide quantum dot nanoparticles against breast cancer stem-like cells

Cancer stem cells (CSCs) play an essential role in cancer development, metastasis, relapse, and resistance to treatment. In this article, the effects of three synthesized ZnO nanofluids on proliferation, apoptosis, and stemness markers of breast cancer stem-like cells are reported. The antiproliferative and apoptotic properties of ZnO nanoparticles were evaluated on breast cancer stem-like cell-enriched mammospheres by MTS assay and flowcytometry, respectively. The expression of stemness markers, including WNT1, NOTCH1, β-catenin, CXCR4, SOX2, and ALDH3A1 was assessed by real-time PCR. Western blotting was used to analyze the phosphorylation of Janus kinase 2 (JAK2) and Signal Transducer and Activator of Transcription 3 (STAT3). Markers of stemness were significantly decreased by ZnO nanofluids, especially sample (c) with code ZnO-148 with a different order of addition of polyethylene glycol solution at the end of formulation, which considerably decreased all the markers compared to the controls. All the studied ZnO nanofluids considerably reduced viability and induced apoptosis of spheroidal and parental cells, with ZnO-148 presenting the most effective activity. Using CD95L as a death ligand and ZB4 as an extrinsic apoptotic pathway blocker, it was revealed that none of the nanoparticles induced apoptosis through the extrinsic pathway. Results also showed a marked inhibition of the JAK/STAT pathway by ZnO nanoparticles; confirmed by downregulation of Mcl-1 and Bcl-XL expression. The present data demonstrated that ZnO nanofluids could combat breast CSCs via decreasing stemness markers, stimulating apoptosis, and suppressing JAK/STAT activity.

Role of Moringa oleifera on Green Synthesis of Metal/Metal Oxide Nanomaterials

Being an environmentally benign method biosynthesis of nanomaterial paying much more attention to researchers, it has many advantages over other routes, such as one pot, facile synthesis, and cost‐effective; synthesized material can have good affinity due to surface modification and hence became a most attractive candidate for medicinal and biological applications. Moreover, biosynthesis creates a bridge of interdisciplinary research. Biosynthesis can be done by using bacteria, microbes, plant extracts, etc. In this study, we focus on the synthesis of some metal and metal oxide nanomaterials (M/MO NMs) by using an extract of parts from the Moringa oleifera plant. It is a natural source that can serve as a capping, stabilizing, and reducing/oxidizing agent due to the presence of some of the phytochemical parameters. Moreover, it is a rich source of antioxidants, including quercetin and chlorogenic acids, such as flavonoids, phenolics, astragalin, anthocyanins, cinnamates, and carotenoids, as well as a good source of carotene, iron, potassium, calcium, terpenes, quinines, saponins, alkaloids, proteins, tannins, and vitamin. These components produce smaller particles and give a compelling impact on the activities of M/MO NMs nanoparticles. Here, we discuss nanoparticles such as FeO, CuO, ZnO, NiO, MgO, Ag, and Au.

The reversal of drug resistance by two-dimensional titanium carbide Ti2 C (2D Ti2C) in non-small-cell lung cancer via the depletion of intracellular antioxidant reserves

Background

Chemoresistance is a major barrier limiting the therapeutic efficacy of late stage non‐small cell lung cancer (NSCLC). In this study, we sought to use two‐dimensional titanium carbide (2D Ti₂C) to reverse cisplatin resistance in NSCLC.

Methods

We first achieved favorable properties as a potential anti‐tumor agent. We then compared cell viability and cisplatin uptake in chemoresistant NSCLC cells before and after the use of 2D Ti₂C. Afterwards, we explored the effects of 2D Ti₂C on intracellular antioxidant reserves, followed by evaluating the subsequent changes in the expression of core drug resistance genes. Finally, we confirmed the tumor inhibitory effect and bio‐safety of 2D Ti₂C in a drug‐resistant lung cancer model in nude mice.

Results

Due to the properties of thin layer, large specific surface area, and abundant reactive groups on the surface, 2D Ti₂C can deplete the antioxidant reserve systems such as the glutathione redox buffer system, γ‐glutamylcysteine synthetase (γ‐GCS), glutathione peroxidase (GPx), glutathione‐S‐transferase‐Pi (GST‐π), and metallothionein (MT), thereby increasing the intracellular accumulation of cisplatin and decreasing the expression of drug resistance genes.

Conclusions

2D Ti₂C can reverse NSCLC chemoresistance both in vitro and in vivo, suggesting that it may potentially become a novel and effective means to treat chemoresistant NSCLC in the clinic.

Functionalized Nanoparticles Targeting Tumor-Associated Macrophages as Cancer Therapy

The tumor microenvironment (TME) plays a central role in regulating antitumor immune responses. As an important part of the TME, alternatively activated type 2 (M2) macrophages drive the development of primary and secondary tumors by promoting tumor cell proliferation, tumor angiogenesis, extracellular matrix remodeling and overall immunosuppression. Immunotherapy approaches targeting tumor-associated macrophages (TAMs) in order to reduce the immunosuppressive state in the TME have received great attention. Although these methods hold great potential for the treatment of several cancers, they also face some limitations, such as the fast degradation rate of drugs and drug-induced cytotoxicity of organs and tissues. Nanomedicine formulations that prevent TAM signaling and recruitment to the TME or deplete M2 TAMs to reduce tumor growth and metastasis represent encouraging novel strategies in cancer therapy. They allow the specific delivery of antitumor drugs to the tumor area, thereby reducing side effects associated with systemic application. In this review, we give an overview of TAM biology and the current state of nanomedicines that target M2 macrophages in the course of cancer immunotherapy, with a specific focus on nanoparticles (NPs). We summarize how different types of NPs target M2 TAMs, and how the physicochemical properties of NPs (size, shape, charge and targeting ligands) influence NP uptake by TAMs in vitro and in vivo in the TME. Furthermore, we provide a comparative analysis of passive and active NP-based TAM-targeting strategies and discuss their therapeutic potential.

Ribosome profiling reveals translatome remodeling in cancer cells in response to zinc oxide nanoparticles

The anticancer effect of zinc oxide nanoparticles (ZnO NPs) largely relies on cellular responses such as alteration of gene expression. Although ZnO NPs have been reported to induce transcriptional changes, the potential of ZnO NPs to affect cellular translatome remains largely unknown. Using ribosome profiling, we demonstrated that the transcription of 78 genes and the translation of 1,448 genes are affected during one hour of ZnO NPs exposure in A549 human lung cancer cells. The mitogen-activated protein kinase (MAPK) pathway is up-regulated upon ZnO NP treatment. The upstream open reading frame (uORF) plays a pervasive role in the induction of up-regulated genes, including TLNRD1 and CCNB1IP1. Knockdown of TLNRD1 or CCNB1IP1 reduces ZnO NP-induced cytotoxicity. Together, our study characterizes the landscape of translational alteration under ZnO NPs treatment and provides potential targets to augment the anticancer effect of ZnO NPs.

Caspofungin-resistance in Candida auris is cell wall-dependent phenotype and potential prevention by zinc oxide nanoparticles

Candida auris is an emergent nosocomial multi-drug-resistant yeast that represents a global health threat. Recently, C. auris clinical isolates with caspofungin resistance were identified. Mutation in FKS1 gene was determined as a mechanism of resistance. However, the ability of C. auris to develop acquired and cross-resistance has never been investigated. Herein, this resistance ability due to caspofungin and associate mechanisms were investigated. C. auris clinical isolate was successively cultured for 10 generations in the presence of caspofungin compared to fluconazole-treatment and untreated controls. This was followed by the analysis of target gene expression and phenotypic changes. The obtained results showed that caspofungin-treated C. auris exhibited elevated MIC50(caspofungin), slower growth, elevated chitin content, overexpression of caspofungin target genes, and cross-resistance to fluconazole. Interestingly, caspofungin exposure induced cell-cell adhesion and biofilm formation. C. auris gradually lost caspofungin resistance after removal of antifungal pressure, while keeping the overexpression of fungal cell wall-related genes including ALS5. We propose that C. auris ageing in the presence of caspofungin caused the development of persistent phenotypic changes in the fungal cell wall, leading to acquired and physical cross-resistance mechanisms. Surprisingly, formulation of caspofungin in zinc oxide nanoparticles prevented the aforementioned behavioral changes regardless of the pathogen generations.

LAY SUMMARY

Candida auris developed resistance against caspofungin. Our data indicated that this resistance mechanism is unique because of changes in the genes related to cell wall adhesions. Formulation of caspofungin in ZnO nanoparticles was able to overcome these phenotypic changes.