Bespoken Nanoceria: An Effective Treatment in Experimental Hepatocellular Carcinoma

Chronic stress influences the macrophage M1-M2 polarization balance through β-adrenergic signaling in hepatoma mice

Chronic stress negatively affects the immune system and promotes tumor progression. Tumor-associated macrophage (TAM) is an important component of the tumor immune microenvironment. However, the influence of chronic stress on M1-M2 polarization of TAM is unclear. We used flow cytometry to measure the M1-M2 polarization of TAM in chronic stress hepatocellular carcinoma (HCC) bearing mice. We also measured the level of norepinephrine and blocked β-adrenergic signaling to explore the role of β-adrenergic receptor in the effect of chronic stress on M1-M2 polarization of TAM. We found that chronic stress disrupts the M1-M2 polarization in tumor tissues, increased the level of CD11b+Ly6C+CCR2+ monocyte and interleukin-1beta in blood and promoted the growth of HCC. Furthermore, chronic stress upregulated the level of CCL2 in tumor tissues. Finally, we found chronic stress increased norepinephrine level in serum and propranolol, a blocker of β-adrenergic signaling, inhibited HCC growth, recovered the M1-M2 polarization balance of TAM in tumor tissues, blocked the increase of CD11b+Ly6C+CCR2+ monocytes in blood, and blocked the increase of CCL2 in tumor tissues induced by chronic stress. Our study indicated that chronic stress disrupts the M1-M2 polarization balance of TAMs through β-adrenergic signaling, thereby promoting the growth of HCC.

Recent advances in hepatocellular carcinoma-targeted nanoparticles

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

Nanoceria-Mediated Cyclosporin A Delivery for Dry Eye Disease Management through Modulating Immune-Epithelial Crosstalk

Dry eye disease (DED) affects a substantial worldwide population with increasing frequency. Current single-targeting DED management is severely hindered by the existence of an oxidative stress-inflammation vicious cycle and complicated intercellular crosstalk within the ocular microenvironment. Here, a nanozyme-based eye drop, namely nanoceria loading cyclosporin A (Cs@P/CeO2), is developed, which possesses long-term antioxidative and anti-inflammatory capacities due to its regenerative antioxidative activity and sustained release of cyclosporin A (CsA). In vitro studies showed that the dual-functional Cs@P/CeO2 not only inhibits cellular reactive oxygen species production, sequentially maintaining mitochondrial integrity, but also downregulates inflammatory processes and repolarizes macrophages. Moreover, using flow cytometric and single-cell sequencing data, the in vivo therapeutic effect of Cs@P/CeO2 was systemically demonstrated, which rebalances the immune-epithelial communication in the corneal microenvironment with less inflammatory macrophage polarization, restrained oxidative stress, and enhanced epithelium regeneration. Collectively, our data proved that the antioxidative and anti-inflammatory Cs@P/CeO2 may provide therapeutic insights into DED management.

Cerium oxide nanoparticles: Chemical properties, biological effects and potential therapeutic opportunities (Review)

The chemistry of pure cerium oxide (CeO2-x) nanoparticles has been widely studied since the 1970s, especially for chemical catalysis. CeO2-x nanoparticles have been included in an important class of industrial metal oxide nanoparticles and have been attributed a range of wide applications, such as ultraviolet absorbers, gas sensors, polishing agents, cosmetics, consumer products, high-tech devices and fuel cell conductors. Despite these early applications in the field of chemistry, the biological effects of CeO2-x nanoparticles were only explored in the 2000s. Since then, CeO2-x nanoparticles have gained a spot in research related to various diseases, especially the ones in which oxidative stress plays a part. Due to an innate oxidation state variation on their surface, CeO2-x nanoparticles have exhibited redox activities in diseases, such as cancer, acting either as an oxidizing agent, or as an antioxidant. In biological models, CeO2-x nanoparticles have been shown to modulate cancer cell viability and, more recently, cell death pathways. However, a deeper understanding on how the chemical structure of CeO2-x nanoparticles (including nanoparticle size, shape, suspension, agglomeration in the medium used, pH of the medium, type of synthesis and crystallite size) influences the cellular effects observed remains to be elucidated. In the present review, the chemistry of CeO2-x nanoparticles and their impact on biological models and modulation of cell signalling, particularly focusing on oxidative and cell death pathways, were investigated. The deeper understanding of the chemical activity of CeO2-x nanoparticles may provide the rationale for further biomedical applications towards disease treatment and drug delivery purposes.

MRPL48 is a novel prognostic and predictive biomarker of hepatocellular carcinoma

BACKGROUND

Hepatocellular carcinoma (HCC) is one of the most prevalent forms of cancer and poses a threat to the health and survival of humans. Mitochondrial ribosomal protein L48 (MRPL48) belongs to the mitochondrial ribosomal protein family, which participates in energy production. Studies have shown that MRPL48 can predict osteosarcoma incidence and prognosis, as well as promotes colorectal cancer progression. However, the role of MRPL48 in HCC remains unknown.

METHODS

TCGA, GEO, HCCDB, CPTAC, SMART, UALCAN, Kaplan-Meier plotter, cBioPortal, and MethSurv were performed for bioinformatics purposes. Quantitative RT-PCR, immunoblotting, and functional studies were conducted to validate the methodology in vitro.

RESULTS

MRPL48 was greatly overexpressed in HCC tissues, compared with healthy tissue, which was subsequently demonstrated in vitro as well. The survival and regression analyses showed that MRPL48 expression is of significant clinical prognostic value in HCC. The ROC curve and nomogram analysis indicated that MRPL48 is a powerful predictor of HCC. MRPL48 methylation was adversely associated with the expression of MRPL48, and patients with a low level of methylation had poorer overall survival than those with a high level of methylation. GSEA showed that the expression of the MRPL48 was correlated with Resolution of Sister Chromatid Cohesion, Mitotic Prometaphase, Retinoblastoma Gene in Cancer, RHO Gtpases Activate Formins, Mitotic Metaphase and Anaphase, and Cell Cycle Checkpoints. An analysis of immune cell infiltration showed a significant association between MRPL48 and immune cell infiltration subsets, which impacted the survival of HCC patients. Additionally, MRPL48 knockdown reduced HCC cell proliferation, migration, and invasion in vitro.

CONCLUSIONS

We demonstrated that MRPL48 expression may be associated with HCC development and prognosis. These findings may open up new research directions and opportunities for the development of HCC treatments.

Effectiveness of Cerium Oxide Nanoparticles in Non-Alcoholic Fatty Liver Disease Evolution Using In Vivo and In Vitro Studies: A Systematic Review

Nonalcoholic fatty liver disease (NAFLD) describes a spectrum of liver abnormalities, from benign steatosis to nonalcoholic steatohepatitis (NASH). Because of their antioxidant capabilities, CeNPs have sparked a lot of interest in biological applications. This review evaluated the effectiveness of CeNPs in NAFLD evolution through in vivo and in vitro studies. Databases such as MEDLINE, EMBASE, Scopus, and Web of Science were looked for studies published between 2012 and June 2023. Quality was evaluated using PRISMA guidelines. We looked at a total of nine primary studies in English carried out using healthy participants or HepG2 or LX2 cells. Quantitative data such as blood chemical markers, lipid peroxidation, and oxidative status were obtained from the studies. Our findings indicate that NPs are a possible option to make medications safer and more effective. In fact, CeNPs have been demonstrated to decrease total saturated fatty acids and foam cell production (steatosis), reactive oxygen species production and TNF-α (necrosis), and vacuolization in hepatic tissue when used to treat NAFLD. Thus, CeNP treatment may be considered promising for liver illnesses. However, limitations such as the variation in durations between studies and the utilization of diverse models to elucidate the etiology of NAFLD must be considered. Future studies must include standardized NAFLD models.

Cerium oxide nanoparticles-carrying human umbilical cord mesenchymal stem cells counteract oxidative damage and facilitate tendon regeneration

BACKGROUND

Tendon injuries have a high incidence and limited treatment options. Stem cell transplantation is essential for several medical conditions like tendon injuries. However, high local concentrations of reactive oxygen species (ROS) inhibit the activity of transplanted stem cells and hinder tendon repair. Cerium oxide nanoparticles (CeONPs) have emerged as antioxidant agents with reproducible reducibility.

RESULTS

In this study, we synthesized polyethylene glycol-packed CeONPs (PEG-CeONPs), which were loaded into the human umbilical cord mesenchymal stem cells (hUCMSCs) to counteract oxidative damage. H2O2 treatment was performed to evaluate the ROS scavenging ability of PEG-CeONPs in hUCMSCs. A rat model of patellar tendon defect was established to assess the effect of PEG-CeONPs-carrying hUCMSCs in vivo. The results showed that PEG-CeONPs exhibited excellent antioxidant activity both inside and outside the hUCMSCs. PEG-CeONPs protect hUCMSCs from senescence and apoptosis under excessive oxidative stress. Transplantation of hUCMSCs loaded with PEG-CeONPs reduced ROS levels in the tendon injury area and facilitated tendon healing. Mechanistically, NFκB activator tumor necrosis factor α and MAPK activator dehydrocrenatine, reversed the therapeutic effect of PEG-CeONPs in hUCMSCs, indicating that PEG-CeONPs act by inhibiting the NFκB and MAPK signaling pathways.

CONCLUSIONS

The carriage of the metal antioxidant oxidase PEG-CeONPs maintained the ability of hUCMSCs in the injured area, reduced the ROS levels in the microenvironment, and facilitated tendon regeneration. The data presented herein provide a novel therapeutic strategy for tendon healing and new insights into the use of stem cells for disease treatment.

Structural and functional insights in polysaccharides coated cerium oxide nanoparticles and their potential biomedical applications: A review

Cerium oxide nanoparticles have now significant presence in biomedical fields due to their wide applications; however, challenges regarding their safety and biocompatibility persist. Polysaccharides based biopolymers have inherent hydroxyl and carboxyl groups, enabling them to govern the surface functionalization of cerium oxide nanoparticles, hence their chemical and physical characteristics. Because of this, polysaccharides such as dextran, alginate, pullulan, chitosan, polylactic acid, starch, and pectin are practical substitutes for the conventional coatings used to synthesize cerium oxide nanoparticles. This review discusses the effect of biopolymer coatings on the properties of cerium oxide nanoparticles, such as size, stability, aggregation, and biocompatibility. Additionally, it also summarises various biomedical applications of polysaccharides coated cerium oxide nanoparticles, such as in bone tissue regeneration, liver inflammation, wound healing, and antibacterial and anticancer activities. Biocompatible cerium oxide nanoparticles will surely improve their applications in the biomedical field.

Antioxidant and Prooxidant Nanozymes: From Cellular Redox Regulation to Next-Generation Therapeutics

Nanozymes, nanomaterials with enzyme-mimicking activity, have attracted tremendous interest in recent years owing to their ability to replace natural enzymes in various biomedical applications, such as biosensing, therapeutics, drug delivery, and bioimaging. In particular, the nanozymes capable of regulating the cellular redox status by mimicking the antioxidant enzymes in mammalian cells are of great therapeutic significance in oxidative-stress-mediated disorders. As the distinction of physiological oxidative stress (oxidative eustress) and pathological oxidative stress (oxidative distress) occurs at a fine borderline, it is a great challenge to design nanozymes that can differentially sense the two extremes in cells, tissues and organs and mediate appropriate redox chemical reactions. In this Review, we summarize the advances in the development of redox-active nanozymes and their biomedical applications. We primarily highlight the therapeutic significance of the antioxidant and prooxidant nanozymes in various disease model systems, such as cancer, neurodegeneration, and cardiovascular diseases. The future perspectives of this emerging area of research and the challenges associated with the biomedical applications of nanozymes are described.

From liver fibrosis to hepatocarcinogenesis: Role of excessive liver H2O2 and targeting nanotherapeutics

Liver fibrosis and hepatocellular carcinoma (HCC) have been worldwide threats nowadays. Liver fibrosis is reversible in early stages but will develop precancerosis of HCC in cirrhotic stage. In pathological liver, excessive H₂O₂ is generated and accumulated, which impacts the functionality of hepatocytes, Kupffer cells (KCs) and hepatic stellate cells (HSCs), leading to genesis of fibrosis and HCC. H₂O₂ accumulation is associated with overproduction of superoxide anion (O₂^•−) and abolished antioxidant enzyme systems. Plenty of therapeutics focused on H₂O₂ have shown satisfactory effects against liver fibrosis or HCC in different ways. This review summarized the reasons of liver H₂O₂ accumulation, and the role of H₂O₂ in genesis of liver fibrosis and HCC. Additionally, nanotherapeutics targeting H₂O₂ were summarized for further consideration of antifibrotic or antitumor therapy.

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Liver fibrosis and HCC are closely related because ROS induced liver damage and inflammation, especially over-cumulated H₂O₂.

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Excess H₂O₂ diffusion in pathological liver was due to increased metabolic rate and diminished cellular antioxidant systems.

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Freely diffused H₂O₂ damaged liver-specific cells, thereby leading to fibrogenesis and hepatocarcinogenesis.

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Nanotherapeutics targeting H₂O₂ are summarized for treatment of liver fibrosis and HCC, and also challenges are proposed.

Exploring the Long-Term Tissue Accumulation and Excretion of 3 nm Cerium Oxide Nanoparticles after Single Dose Administration

Nanoparticle (NP) pharmacokinetics significantly differ from traditional small molecule principles. From this emerges the need to create new tools and concepts to harness their full potential and avoid unnecessary risks. Nanoparticle pharmacokinetics strongly depend on size, shape, surface functionalisation, and aggregation state, influencing their biodistribution, accumulation, transformations, and excretion profile, and hence their efficacy and safety. Today, while NP biodistribution and nanoceria biodistribution have been studied often at short times, their long-term accumulation and excretion have rarely been studied. In this work, 3 nm nanoceria at 5.7 mg/kg of body weight was intravenously administrated in a single dose to healthy mice. Biodistribution was measured in the liver, spleen, kidney, lung, brain, lymph nodes, ovary, bone marrow, urine, and faeces at different time points (1, 9, 30, and 100 days). Biodistribution and urinary and faecal excretion were also studied in rats placed in metabolic cages at shorter times. The similarity of results of different NPs in different models is shown as the heterogeneous nanoceria distribution in organs. After the expectable accumulation in the liver and spleen, the concentration of cerium decays exponentially, accounting for about a 50% excretion of cerium from the body in 100 days. Cerium ions, coming from NP dissolution, are most likely excreted via the urinary tract, and ceria nanoparticles accumulated in the liver are most likely excreted via the hepatobiliary route. In addition, nanoceria looks safe and does not damage the target organs. No weight loss or apathy was observed during the course of the experiments.

Targeting tumor-associated macrophages in hepatocellular carcinoma: biology, strategy, and immunotherapy

Hepatocellular carcinoma (HCC), one of the most malignant tumors, is characterized by its stubborn immunosuppressive microenvironment. As one of the main members of the tumor microenvironment (TME) of HCC, tumor-associated macrophages (TAMs) play a critical role in its occurrence and development, including stimulating angiogenesis, enhancing immunosuppression, and promoting the drug resistance and cancer metastasis. This review describes the origin as well as phenotypic heterogeneity of TAMs and their potential effects on the occurrence and development of HCC and also discusses about various adjuvant therapy based strategies that can be used for targeting TAMs. In addition, we have highlighted different treatment modalities for TAMs based on immunotherapy, including small molecular inhibitors, immune checkpoint inhibitors, antibodies, tumor vaccines, adoptive cellular immunotherapy, and nanocarriers for drug delivery, to explore novel combination therapies and provide feasible therapeutic options for clinically improving the prognosis and quality of life of HCC patients.

Nanoceria: an innovative strategy for cancer treatment

Nanoceria or cerium oxide nanoparticles characterised by the co-existing of Ce³⁺ and Ce⁴⁺ that allows self-regenerative, redox-responsive dual-catalytic activities, have attracted interest as an innovative approach to treating cancer. Depending on surface characteristics and immediate environment, nanoceria exerts either anti- or pro-oxidative effects which regulate reactive oxygen species (ROS) levels in biological systems. Nanoceria mimics ROS-related enzymes that protect normal cells at physiological pH from oxidative stress and induce ROS production in the slightly acidic tumour microenvironment to trigger cancer cell death. Nanoceria as nanozymes also generates molecular oxygen that relieves tumour hypoxia, leading to tumour cell sensitisation to improve therapeutic outcomes of photodynamic (PDT), photothermal (PTT) and radiation (RT), targeted and chemotherapies. Nanoceria has been engineered as a nanocarrier to improve drug delivery or in combination with other drugs to produce synergistic anti-cancer effects. Despite reported preclinical successes, there are still knowledge gaps arising from the inadequate number of studies reporting findings based on physiologically relevant disease models that accurately represent the complexities of cancer. This review discusses the dual-catalytic activities of nanoceria responding to pH and oxygen tension gradient in tumour microenvironment, highlights the recent nanoceria-based platforms reported to be feasible direct and indirect anti-cancer agents with protective effects on healthy tissues, and finally addresses the challenges in clinical translation of nanoceria based therapeutics.

Rare earth cerium oxide nanoparticles attenuated liver fibrosis in bile duct ligation mice model

Liver fibrosis is one of the major liver complications which eventually progresses to liver cirrhosis and liver failure. Cerium oxide nanoparticles, also known as nanoceria (NC) are nanoparticles with potential antioxidant and anti-inflammatory activities. Herein, we evaluated the hepatoprotective and anti-fibrotic effects of nanoceria (NC) against bile duct ligation (BDL) induced liver injury. NC were administered i.p. for 12 days (0.5 and 2 mg/kg) to C57BL/6J mice. The biochemical markers of liver injury, oxidative and nitrosative stress markers, inflammatory cytokines were evaluated. Fibrosis assessment and mechanistic studies were conducted to assess the hepatoprotective effects of NC. Administration of NC proved to significantly ameliorate liver injury as evident by reduction in SGOT, SGPT, ALP and bilirubin levels in the treated animals. NC treatment significantly reduced the hydroxyproline levels and expression of fibrotic markers. In summary, our findings establish the hepatoprotective and anti-fibrotic effects of NC against BDL induced liver injury and liver fibrosis. These protective effects were majorly ascribed to their potential ROS inhibition and antioxidant activities through catalase, superoxide dismutase (SOD)-mimetic properties and auto-regenerating capabilities.

Tumor-associated macrophages in liver cancer: From mechanisms to therapy

Multidimensional analyses have demonstrated the presence of a unique tumor microenvironment (TME) in liver cancer. Tumor-associated macrophages (TAMs) are among the most abundant immune cells infiltrating the TME and are present at all stages of liver cancer progression, and targeting TAMs has become one of the most favored immunotherapy strategies. In addition, macrophages and liver cancer cells have distinct origins. At the early stage of liver cancer, macrophages can provide a niche for the maintenance of liver cancer stem cells. In contrast, cancer stem cells (CSCs) or poorly differentiated tumor cells are key factors modulating macrophage activation. In the present review, we first propose the origin connection between precursor macrophages and liver cancer cells. Macrophages undergo dynamic phenotypic transition during carcinogenesis. In this course of such transition, it is critical to determine the appropriate timing for therapy and block specific markers to suppress pro-tumoral TAMs. The present review provides a more detailed discussion of transition trends of such surface markers than previous reviews. Complex crosstalk occurs between TAMs and liver cancer cells. TAMs play indispensable roles in tumor progression, angiogenesis, and autophagy due to their heterogeneity and robust plasticity. In addition, macrophages in the TME interact with other immune cells by directing cell-to-cell contact or secreting various effector molecules. Similarly, tumor cells combined with other immune cells can drive macrophage recruitment and polarization. Despite the latest achievements and the advancements in treatment strategies following TAMs studies, comprehensive discussions on the communication between macrophages and cancer cells or immune cells in liver cancer are currently lacking. In this review, we discussed the interactions between TAMs and liver cancer cells (from cell origin to maturation), the latest therapeutic strategies (including chimeric antigen receptor macrophages), and critical clinical trials for hepatocellular carcinoma (HCC) and intrahepatic cholangiocarcinoma (iCCA) to provide a rationale for further clinical investigation of TAMs as a potential target for treating patients with liver cancer.

Calotropis gigantea stem bark extracts inhibit liver cancer induced by diethylnitrosamine

Several fractions of Calotropis gigantea extracts have been proposed to have potential anticancer activity in many cancer models. The present study evaluated the anticancer activity of C. gigantea stem bark extracts in liver cancer HepG2 cells and diethylnitrosamine (DEN)-induced primary liver cancer in rats. The carcinogenesis model induced by DEN administration has been widely used to study pathophysiological features and responses in rats that are comparable to those seen in cancer patients. The dichloromethane (CGDCM), ethyl acetate, and water fractions obtained from partitioning crude ethanolic extract were quantitatively analyzed for several groups of secondary metabolites and calactin contents. A combination of C. gigantea stem bark extracts with doxorubicin (DOX) was assessed in this study to demonstrate the enhanced cytotoxic effect to cancer compared to the single administration. The combination of DOX and CGDCM, which had the most potential cytotoxic effect in HepG2 cells when compared to the other three fractions, significantly increased cytotoxicity through the apoptotic effect with increased caspase-3 expression. This combination treatment also reduced ATP levels, implying a correlation between ATP and apoptosis induction. In a rat model of DEN-induced liver cancer, treatment with DOX, C. gigantea at low (CGDCM-L) and high (CGDCM-H) doses, and DOX + CGDCM-H for 4 weeks decreased the progression of liver cancer by lowering the liver weight/body weight ratio and the occurrence of liver hyperplastic nodules, fibrosis, and proliferative cells. The therapeutic applications lowered TNF-α, IL-6, TGF-β, and α-SMA inflammatory cytokines in a similar way, implying that CGDCM had a curative effect against the inflammation-induced liver carcinogenesis produced by DEN exposure. Furthermore, CGDCM and DOX therapy decreased ATP and fatty acid synthesis in rat liver cancer, which was correlated with apoptosis inhibition. CGDCM reduced cleaved caspase-3 expression in liver cancer rats when used alone or in combination with DOX, implying that apoptosis-inducing hepatic carcinogenesis was suppressed. Our results also verified the low toxicity of CGDCM injection on the internal organs of rats. Thus, this research clearly demonstrated a promising, novel anticancer approach that could be applied in future clinical studies of CGDCM and combination therapy.

Cerium oxide nanoparticles administration during machine perfusion of discarded human livers: A pilot study

The combined approach of ex situ normothermic machine perfusion (NMP) and nanotechnology represents a strategy to mitigate ischemia/reperfusion injury in liver transplantation (LT). We evaluated the uptake, distribution, and efficacy of antioxidant cerium oxide nanoparticles (nanoceria) during normothermic perfusion of discarded human livers. A total of 9 discarded human liver grafts were randomized in 2 groups and underwent 4 h of NMP: 5 grafts were treated with nanoceria conjugated with albumin (Alb-NC; 50 µg/ml) and compared with 4 untreated grafts. The intracellular uptake of nanoceria was analyzed by electron microscopy (EM) and inductively coupled plasma-mass spectrometry (ICP-MS). The antioxidant activity of Alb-NC was assayed in liver biopsies by glutathione (GSH), superoxide dismutase (SOD) and catalase (CAT) assay, telomere length, and 4977-bp common mitochondrial DNA deletion (mtDNA⁴⁹⁷⁷ deletion). The cytokine profile was evaluated in perfusate samples. EM and ICP-MS confirmed Alb-NC internalization, rescue of mitochondrial phenotype, decrease of lipid droplet peroxidation, and lipofuscin granules in the treated grafts. Alb-NC exerted an antioxidant activity by increasing GSH levels (percentage change: +94% ± 25%; p = 0.01), SOD (+17% ± 4%; p = 0.02), and CAT activity (51% ± 23%; p = 0.03), reducing the occurrence of mtDNA⁴⁹⁷⁷ deletion (-67.2% ± 11%; p = 0.03), but did not affect cytokine release. Alb-NC during ex situ perfusion decreased oxidative stress, upregulating graft antioxidant defense. They could be a tool to improve quality grafts during NMP and represent an antioxidant strategy aimed at protecting the graft against reperfusion injury during LT.

Tryptophan-sorbitol based carbon quantum dots for theranostics against hepatocellular carcinoma

Background

Despite novel advances in screening, targeting and immunotherapies, early diagnosis and satisfactory treatments against hepatocellular carcinoma (HCC) remain formidable challenges. Given the unique advantages, carbon quantum dots (CQDs) become a smart theranostic nanomaterial for cancer diagnosis and therapy.

Results

In this work, a type of bio-friendly CQDs, trichrome-tryptophan-sorbitol CQDs (TC-WS-CQDs), is synthesized from natural biocompatible tryptophan via the one-pot hydrothermal method. Compared with normal hepatocytes, a much stronger green fluorescence is detected in HCC cells, indicating the ability of TC-WS-CQDs to target HCC cells. Furthermore, green-emitting TC-WS-CQDs generate large amounts of reactive oxygen species (ROS), leading to autophagy of HCC cells. Additionally, the green-emitting TC-WS-CQDs perform significant tumor inhibition by inducing autophagy via p53-AMPK pathway in vitro and in vivo studies with almost no systemic toxicity.

Conclusions

The results may highlight a promising anticancer nanotheranostic strategy with integration of diagnosis, targeting, and therapy.

Graphical Abstract

Advanced applications of cerium oxide based nanozymes in cancer

Cerium oxide nanozymes have emerged as a new type of bio-antioxidants in recent years. CeO2 nanozymes possess enzyme mimetic activities with outstanding free radical scavenging activity, facile synthesis conditions, and excellent biocompatibility. Based on these extraordinary properties, use of CeO2 nanozymes has been demonstrated to be a highly versatile therapeutic method for many diseases, such as for inflammation, rheumatoid arthritis, hepatic ischemia-reperfusion injury and Alzheimer's disease. In addition to that, CeO2 nanozymes have been widely used in the diagnosis and treatment of cancer. Many examples can be found in the literature, such as magnetic resonance detection, tumour marker detection, chemotherapy, radiotherapy, photodynamic therapy (PDT), and photothermal therapy (PTT). This review systematically summarises the latest applications of CeO2-based nanozymes in cancer research and treatment. We believe that this paper will help develop value-added CeO2 nanozymes, offering great potential in the biotechnology industry and with great significance for the diagnosis and treatment of a wide range of malignancies.

Targeting Killing of Tumor Cells Based on Isoelectric Point Suitable Nanoceria-rod with High Oxygen Vacancies

Nanozymes have great potential application in tumor treatment because of their good stability, high biocompatibility, easy preparation and versatility. However, it remains a challenge to design of highly active nanozyme...

The use of cerium oxide nanoparticles in liver disorders: A double-sided coin?

Being recognized as the first antioxidant nanoparticles (NPs) proposed for medicine, cerium oxide nanoparticles (CeO₂ NPs) have recently gained tremendous attention for their vast biomedical applications. Nevertheless, inconsistent reports of either medical benefits or toxicity have created an atmosphere of uncertainty hindering their clinical utilization. Like other nanoparticles advocated as a promising protective/therapeutic option, CeO₂ NPs are sometimes questioned as a health threat. As CeO₂ NPs tend to accumulate in the liver after intravenous injection, liver is known to represent the key tissue to test for their therapeutic/toxicological effects. However, more research evidence is still needed before any conclusions can be elicited about the mechanisms by which CeO₂ NPs could be harmful or protective/therapeutic to the liver tissue. A proper understanding of such discrepancies is warranted to plan for further modifications to mitigate any side effects. Therefore, in this MiniReview, we tried to demonstrate the two sides of the same coin, CeO₂ NPs, within the liver context. As well, we highlighted a few promising strategies by which the negatives of CeO₂ NPs could be diminished while enhancing all the positives.

The Interactions between Nanoparticles and the Innate Immune System from a Nanotechnologist Perspective

The immune system contributes to maintaining the body’s functional integrity through its two main functions: recognizing and destroying foreign external agents (invading microorganisms) and identifying and eliminating senescent cells and damaged or abnormal endogenous entities (such as cellular debris or misfolded/degraded proteins). Accordingly, the immune system can detect molecular and cellular structures with a spatial resolution of a few nm, which allows for detecting molecular patterns expressed in a great variety of pathogens, including viral and bacterial proteins and bacterial nucleic acid sequences. Such patterns are also expressed in abnormal cells. In this context, it is expected that nanostructured materials in the size range of proteins, protein aggregates, and viruses with different molecular coatings can engage in a sophisticated interaction with the immune system. Nanoparticles can be recognized or passed undetected by the immune system. Once detected, they can be tolerated or induce defensive (inflammatory) or anti-inflammatory responses. This paper describes the different modes of interaction between nanoparticles, especially inorganic nanoparticles, and the immune system, especially the innate immune system. This perspective should help to propose a set of selection rules for nanosafety-by-design and medical nanoparticle design.

Cerium Oxide Nanoparticles Alleviate Hepatic Fibrosis Phenotypes In Vitro

Exposure to metallic nanoparticles (NPs) can result in inadvertent NP accumulation in body tissues. While their subsequent cellular interactions can lead to unintended consequences and are generally regarded as detrimental for health, they can on occasion mediate biologically beneficial effects. Among NPs, cerium oxide nanoparticles (CeO₂ NP) possess strong antioxidant properties and have shown to alleviate certain pathological conditions. Herein, we show that the presence of cubic 25 nm CeO₂ NP was able to reduce TGF-β-mediated activation in the cultured hepatic stellate cell line LX2 by reducing oxidative stress levels and TGF-β-mediated signalling. These cells displayed reduced classical liver fibrosis phenotypes, such as diminished fibrogenesis, altered matrix degradation, decreased cell motility, modified contractability and potentially lowered autophagy. These findings demonstrate that CeO₂ NP may be able to ameliorate hepatic fibrosis and suggest a possible therapeutic pathway for an otherwise difficult-to-treat condition.

Nanoceria, the versatile nanoparticles: Promising biomedical applications

Nanotechnology has been a boon for the biomedical field due to the freedom it provides for tailoring of pharmacokinetic properties of different drug molecules. Nanomedicine is the medical application of nanotechnology for the diagnosis, treatment and/or management of the diseases. Cerium oxide nanoparticles (CNPs) are metal oxide-based nanoparticles (NPs) which possess outstanding reactive oxygen species (ROS) scavenging activities primarily due to the availability of "oxidation switch" on their surface. These NP have been found to protect from a number of disorders with a background of oxidative stress such as cancer, diabetes etc. In fact, the CNPs have been found to possess the environment-dependent ROS modulating properties. In addition, the inherent catalase, SOD, oxidase, peroxidase and phosphatase mimetic properties of CNPs provide them superiority over a number of NPs. Further, chemical reactivity of CNPs seems to be a function of their surface chemistry which can be precisely tuned by defect engineering. However, the contradictory reports make it necessary to critically evaluate the potential of CNPs, in the light of available literature. The review is aimed at probing the feasibility of CNPs to push towards the clinical studies. Further, we have also covered and censoriously discussed the suspected negative impacts of CNPs before making our way to a consensus. This review aims to be a comprehensive, authoritative, critical, and accessible review of general interest to the scientific community.

Scalable synthesis of multicomponent multifunctional inorganic core@mesoporous silica shell nanocomposites

Integrating multiple materials with different functionalities in a single nanostructure enables advances in many scientific and technological applications. However, such highly sophisticated nanomaterials usually require complex synthesis processes that complicate their preparation in a sustainable and industrially feasible manner. Herein, we designed a simple general method to grow a mesoporous silica shell onto any combination of hydrophilic nanoparticle cores. The synthetic strategy, based on the adjustment of the key parameters of the sol-gel process for the silica shell formation, allows for the embedment of single, double, and triple inorganic nanoparticles within the same shell, as well as the size-control of the obtained nanocomposites. No additional interfacial adhesive layer is required on the nanoparticle surfaces for the embedding process. Adopting this approach, electrostatically stabilized, small-sized (from 4 to 15 nm) CeO₂, Fe₃O₄, Gd₂O₃, NaYF₄, Au, and Ag cores were used to test the methodology. The mean diameter of the resulting nanocomposites could be as low as 55 nm, with high monodispersity. These are very feasible sizes for biological intervention, and we further observed increased nanoparticle stability in physiological environments. As a demonstration of their increased activity as a result of this, the antioxidant activity of CeO₂ cores was enhanced when in core-shell form. Remarkably, the method is conducted entirely at room temperature, atmospheric conditions, and in aqueous solvent with the use of ethanol as co-solvent. These facile and even "green" synthesis conditions favor scalability and easy preparation of multicomponent nanocomposite libraries with standard laboratory glassware and simple benchtop chemistry, through this sustainable and cost-effective fabrication process.

Nanostructured Ceria: Biomolecular Templates and (Bio)applications

Ceria (CeO2) nanostructures are well-known in catalysis for energy and environmental preservation and remediation. Recently, they have also been gaining momentum for biological applications in virtue of their unique redox properties that make them antioxidant or pro-oxidant, depending on the experimental conditions and ceria nanomorphology. In particular, interest has grown in the use of biotemplates to exert control over ceria morphology and reactivity. However, only a handful of reports exist on the use of specific biomolecules to template ceria nucleation and growth into defined nanostructures. This review focusses on the latest advancements in the area of biomolecular templates for ceria nanostructures and existing opportunities for their (bio)applications.

Mesoporous silica coated CeO2 nanozymes with combined lipid-lowering and antioxidant activity induce long-term improvement of the metabolic profile in obese Zucker rats

Obesity is one of the most important public health problems that is associated with an array of metabolic disorders linked to cardiovascular disease, stroke, type 2 diabetes, and cancer. A sustained therapeutic approach to stop the escalating prevalence of obesity and its associated metabolic comorbidities remains elusive. Herein, we developed a novel nanocomposite based on mesoporous silica coated cerium oxide (CeO₂) nanozymes that reduce the circulating levels of fatty acids and remarkably improve the metabolic phenotype in a model of obese Zucker rats five weeks after its administration. Lipidomic and gene expression analyses showed an amelioration of the hyperlipidemia and of the hepatic and adipose metabolic dysregulations, which was associated with a down-regulation of the hepatic PI3K/mTOR/AKT pathway and a reduction of the M1 proinflammatory cytokine TNF-α. In addition, the coating of the CeO₂ maximized its cell antioxidant protective effects and minimized non-hepatic biodistribution. The one-pot synthesis method for the nanocomposite fabrication is implemented entirely in aqueous solution, room temperature and open atmosphere conditions, favoring scalability and offering a safe and translatable lipid-lowering and antioxidant nanomedicine to treat metabolic comorbidities associated with obesity. This approach may be further applied to address other metabolic disorders related to hyperlipidemia, low-grade inflammation and oxidative stress.

Cerium Oxide Nanoparticles: A New Therapeutic Tool in Liver Diseases

Oxidative stress induced by the overproduction of free radicals or reactive oxygen species (ROS) has been considered as a key pathogenic mechanism contributing to the initiation and progression of injury in liver diseases. Consequently, during the last few years antioxidant substances, such as superoxide dismutase (SOD), resveratrol, colchicine, eugenol, and vitamins E and C have received increasing interest as potential therapeutic agents in chronic liver diseases. These substances have demonstrated their efficacy in equilibrating hepatic ROS metabolism and thereby improving liver functionality. However, many of these agents have not successfully passed the scrutiny of clinical trials for the prevention and treatment of various diseases, mainly due to their unspecificity and consequent uncontrolled side effects, since a minimal level of ROS is needed for normal functioning. Recently, cerium oxide nanoparticles (CeO₂NPs) have emerged as a new powerful antioxidant agent with therapeutic properties in experimental liver disease. CeO₂NPs have been reported to act as a ROS and reactive nitrogen species (RNS) scavenger and to have multi-enzyme mimetic activity, including SOD activity (deprotionation of superoxide anion into oxygen and hydrogen peroxide), catalase activity (conversion of hydrogen peroxide into oxygen and water), and peroxidase activity (reducing hydrogen peroxide into hydroxyl radicals). Consequently, the beneficial effects of CeO₂NPs treatment have been reported in many different medical fields other than hepatology, including neurology, ophthalmology, cardiology, and oncology. Unlike other antioxidants, CeO₂NPs are only active at pathogenic levels of ROS, being inert and innocuous in healthy cells. In the current article, we review the potential of CeO₂NPs in several experimental models of liver disease and their safety as a therapeutic agent in humans as well.

Dysregulation of phosphoproteins in hepatocellular carcinoma revealed via quantitative analysis of the phosphoproteome

Hepatocellular carcinoma (HCC) is one of the most frequently diagnosed types of cancer in the world. Post-translational modifications, such as phosphorylation, serve an essential role during cancer development. To identify aberrant phosphorylation in HCC, a multiplexed tandem mass tag approach combined with liquid chromatography tandem-mass spectrometry was used in the present study. The results are available via ProteomeXchange (identifier no. PXD013934). A total of 4,780 phosphorylated sites distributed on 2,209 proteins were identified and quantified, including 74 and 459 phosphorylated upregulated and downregulated proteins, respectively. Bioinformatic analysis revealed differences and similarities between HCC and normal tissues. Gene Ontology enrichment analysis provided information on biological processes, molecular functions, cellular components and sub-cellular localizations. Protein domains enrichment of differentially expressed proteins was analyzed using InterPro database. Kyoto Encyclopedia of Genes and Genomes enrichment analysis revealed pathways that may potentially be involved in HCC. Integrative analysis of the functions, pathways, motifs of phosphorylated peptides, protein domains and protein interactions established a profile of the phosphoproteome of HCC, which may contribute to identify novel biomarkers for the diagnosis and prognosis of HCC, as well as novel therapeutic targets for HCC treatment.

Recent Advances of Functional Proteomics in Gastrointestinal Cancers- a Path towards the Identification of Candidate Diagnostic, Prognostic, and Therapeutic Molecular Biomarkers

Gastrointestinal (GI) cancer remains one of the common causes of morbidity and mortality. A high number of cases are diagnosed at an advanced stage, leading to a poor survival rate. This is primarily attributed to the lack of reliable diagnostic biomarkers and limited treatment options. Therefore, more sensitive, specific biomarkers and curative treatments are desirable. Functional proteomics as a research area in the proteomic field aims to elucidate the biological function of unknown proteins and unravel the cellular mechanisms at the molecular level. Phosphoproteomic and glycoproteomic studies have emerged as two efficient functional proteomics approaches used to identify diagnostic biomarkers, therapeutic targets, the molecular basis of disease and mechanisms underlying drug resistance in GI cancers. In this review, we present an overview on how functional proteomics may contribute to the understanding of GI cancers, namely colorectal, gastric, hepatocellular carcinoma and pancreatic cancers. Moreover, we have summarized recent methodological developments in phosphoproteomics and glycoproteomics for GI cancer studies.