HCC is considered as one of the leadin causes of death worldwide, with the ability of resistance towards therapeutics. Immunotherapy, particularly ICIs, have provided siginficant insights towards harnessing the immune system. The present review introduces the concepts and possibilities of immunotherapy for HCC treatment, emphasizing its underlying mechanisms and capacity to enhance patient results, focusing on both pre-clinical and clinical insights. The functions of TME and immune evasion mechanisms typical of HCC would be evaluated along with how contemporary immunotherapeutic approaches are designed to address these challenges. Furthermore, the clinical application of immunotherapy in HCC is discussed, emphasizing recent trial findings demonstrating the effectiveness and safety of drugs. In addition, the problems caused by immune evasion and resistance would be discussed to increase potential of immunotherapy along with combination therapy.

Neutrophil extracellular traps (NETs) are web-like, bactericidal structures produced by neutrophils and are composed principally of extracellular DNA, histones, elastase, and myeloperoxidase, among other components. NET formation is an innate immune response that is beneficial for pathogen killing and clearance. However, excessive NET formation and clearance defects can lead to inflammation and induce damage to host organs. NETs are also implicated in the development of noninfectious inflammatory disorders, such as liver injury in chronic liver diseases. The liver parenchyma contains hepatocytes, liver sinusoidal endothelial cells, Kupffer cells, and hepatic stellate cells. Each of these cells possesses unique structures and functions, and their interactions with NETs result in pathophysiological changes contributing to liver injury. This review updates the findings related to the modes of action and molecular mechanisms by which NETs modulate the pathophysiology of various hepatic cells and potentiate liver injury. The article also reviews the roles of NETs in hepatic ischemia reperfusion injury, hepatocellular carcinoma pathogenesis, and cancer metastasis. Last, we examine data to determine whether NETs induce crosstalk among various hepatic cells during liver injury and to identify future research directions.

Hepatocellular carcinoma (HCC) remains a leading cause of cancer-related mortality globally. The tumor microenvironment (TME) plays a pivotal role in HCC progression, characterized by dynamic interactions between stromal components, immune cells, and tumor cells. Key immune players, including tumor-associated macrophages (TAMs), tumor-infiltrating lymphocytes (TILs), cytotoxic T lymphocytes (CTLs), regulatory T cells (Tregs), MDSCs, dendritic cells (DCs), and natural killer (NK) cells, contribute to immune evasion and tumor progression. Recent advances in immunotherapy, such as immune checkpoint inhibitors (ICIs), cancer vaccines, adoptive cell therapy (ACT), and combination therapies, have shown promise in enhancing anti-tumor responses. Dual ICI combinations, ICIs with molecular targeted drugs, and integration with local treatments or radiotherapy have demonstrated improved outcomes in HCC patients. This review highlights the evolving understanding of the immune microenvironment and the therapeutic potential of immunotherapeutic strategies in HCC management.

Psoriasis patients who are obese tend to have serious clinical manifestations and poor responses to various biological agents in most cases. However, the mechanisms by which obesity exacerbates psoriasis remain enigmatic. In this study, we found that the abundance of systemic and localized cutaneous neutrophil extracellular traps (NETs) associated with the obesity-induced aggravation of psoriasis was positively correlated with disease severity and that the inhibition of NETs alleviated psoriatic dermatitis in obese mice. Mechanistically, we found that changes in fatty acid composition in obese subjects resulted in the deposition of saturated fatty acids (SFAs), which promoted the release of NETs via the TLR4-MD2/ROS signaling pathway. We further revealed that NETs potentiate IL-17 inflammation, especially γδT17-mediated immune responses, in obesity-exacerbated psoriasis patients. Moreover, SFAs induced a decreased response to anti-IL17A treatment in psoriasis-like mice, whereas the inhibition of NETs improved the beneficial effects of anti-IL17A in psoriasis-like mice with lipid metabolism disorders. Our findings collectively suggest that SFA-induced NETs play a critical role in the exacerbation of obesity-related psoriasis and provide potential new strategies for the clinical treatment of refractory psoriasis patients with lipid metabolism disorders.

Lenvatinib is a potent first-line therapy for patients with hepatocellular carcinoma (HCC), but it also increased the number of neutrophils in HCC tumor microenvironment.

CitH3, MPO-DNA, elastase and MPO activity were measured for assessing neutrophil extracellular traps (NETs) in vivo and in vitro. Cell cuproptosis was assessed by measurement of copper content, FDX1, and pyruvate. The functions of lenvatinib, DNase I, interleukin 33 (IL33) neutralizing antibody and GPX4 in tumor growth were explored in mice.

Lenvatinib induced NETs in the HCC tumor microenvironment via HCC cells, but not through the direct stimulation of neutrophils. In addition, NET clearance by DNase I improves the efficacy of lenvatinib therapy in HCC mouse models. Mechanistically, lenvatinib promoted the expression and secretion of IL33 by HCC cells that triggered NET formation. Moreover, IL33 knockdown in Hepa1-6 cells improved lenvatinib efficacy in Hepa1-6-bearing HCC model mice and reduced NET formation in the tumor microenvironment. Subsequently, lenvatinib increased IL33 production by increasing the NDUFA4L2 expression in HCC cells. Furthermore, we found that IL33 triggered NET formation in neutrophils by increasing the protein expression of PADI4 via the Akt/mTOR signaling pathway. Rapamycin inhibition of mTOR reduced PADI4 expression and NET formation. Consistently, PADI4 inhibition by the selective PAD4 inhibitor GSK484 hydrochloride (GSK484) improved lenvatinib response to HCC therapy. Importantly, NETs contribute to lenvatinib resistance by inhibiting cuproptosis, but not apoptosis, pyroptosis, or ferroptosis in HCC cells. Treatment with GSK484 reversed the inhibitory effects of NETs on cuproptosis and sensitized the HCC cells to lenvatinib.

Our study revealed that lenvatinib-induced NETs inhibited the cuproptosis of HCC cells, suggesting that targeting the IL33/PADI4/NET axis represents a promising therapeutic strategy for ameliorating lenvatinib resistance in HCC.

Developing drugs for the treatment of Metabolic Associated Steatohepatitis (MASH) has always been a significant challenge. Researchers have been dedicated to exploring drugs and therapeutic strategies to alleviate disease progression, but treatments remain limited. This is partly due to the complexity of the pathophysiological processes, and inadequate knowledge of the cellular and molecular mechanisms in MASH. Especially, the liver non-parenchymal cells (NPCs) like Kupffer cells, hepatic stellate cells and sinusoidal endothelial cells which play critical roles in live function, immune responses, fibrosis and disease progression. Deciphering how these cells function in MASH, would help understand the pathophysiological processes and find potential drug targets. In recent years, new technologies have been developed for single-cell transcriptomic sequencing, making cell-specific transcriptome profiling a reality in healthy and diseased livers. In this review, we discussed how the use of single-cell transcriptomic sequencing provided us with an in-depth understanding of the heterogeneous, cellular interactions among non-parenchymal cells and tried to highlight recent discoveries in MASH by this technology. It is hoped that the summarized features and markers of various subclusters in this review could provide a technical reference for further experiments and a theoretical basis for clinical applications.

The liver has critical digestive, metabolic, and immunosurveillance roles, which get disrupted during liver diseases such as viral hepatitis, fatty liver disease, and hepatocellular carcinoma. While previous research on the pathological development of these diseases has focused on liver-resident immune populations, such as Kupffer cells, infiltrating immune cells responding to pathogens and disease also play crucial roles. Neutrophils are one such key population contributing to hepatic inflammation and disease progression. Belonging to the initial waves of immune response to threats, neutrophils suppress bacterial and viral spread during acute infections and have homeostasis-restoring functions, whereas during chronic insults, they display their plastic nature by responding to the inflammatory environment and develop new phenotypes alongside longer life spans. This review summarizes the diversity in neutrophil function and subpopulations present at steady state, during liver disease, and during liver cancer.

Neutrophils are initial responders in inflammation and contribute to non-alcoholic fatty liver disease (NAFLD) progression to steatohepatitis (NASH). Neutrophil extracellular traps (NETs) are implicated in liver injury, yet their precise mechanisms in NASH progression remains unclear.

This study investigates how NETs drive NASH progression by exacerbating hepatocyte lipotoxicity and explore the regulatory mechanism of NETs formation and its downstream effects on liver pathology.

Clinical samples from NASH patients and diet-induced NASH mice were analyzed for NET levels. NETs were pharmacologically inhibited, and senescent cells were selectively eliminated in mice. Myeloid-specific RBP-J knockout mice were generated to disrupt Notch signaling, with subsequent evaluation of NET formation, senescence markers, steatosis, fibrosis, and inflammation.

NETs were elevated in NASH patients and mice, correlating with hepatocyte senescence and lipotoxicity. Pharmacological NET disruption reduced hepatocyte senescence, accompanied by attenuated steatosis and fibrosis. Senescent cell clearance replicated these improvements, confirming liver senescence emerges is a vital step for NETs to promote the progression of NASH. Myeloid-specific Notch signaling ablation suppressed NET generation, concurrently decreasing lipid deposition and liver inflammation.

Our findings elucidate a novel mechanism by which neutrophil-derived Notch driven NETs exacerbate NASH by promoting cell senescence, thereby contributing to hepatic steatosis and fibrosis. This insight may provide potential intervention strategies and therapeutic targets for NASH treatment.

Metabolic dysfunction-associated steatohepatitis (MASH) fibrosis is a reversible stage of liver disease accompanied by inflammatory cell infiltration. Neutrophils extrude a meshwork of chromatin fibers to establish neutrophil extracellular traps (NETs), which play important roles in inflammatory response regulation. Our previous work demonstrated that NETs promote HCC in MASH. However, it is still unknown if NETs play a role in the molecular mechanisms of liver fibrosis.

Following 12 weeks of Western diet/carbon tetrachloride, MASH fibrosis was identified in C57BL/6 mice with increased NET formation. However, NET depletion using DNase I treatment or mice knocked out for peptidyl arginine deaminase type IV significantly attenuated the development of MASH fibrosis. NETs were demonstrated to induce HSCs activation, proliferation, and migration through augmented mitochondrial and aerobic glycolysis to provide additional bioenergetic and biosynthetic supplies. Metabolomic analysis revealed markedly an altered metabolic profile upon NET stimulation of HSCs that were dependent on arachidonic acid metabolism. Mechanistically, NET stimulation of toll-like receptor 3 induced cyclooxygenase-2 activation and prostaglandin E2 production with subsequent HSC activation and liver fibrosis. Inhibiting cyclooxygenase-2 with celecoxib reduced fibrosis in our MASH model.

Our findings implicate NETs playing a critical role in the development of MASH hepatic fibrosis by inducing metabolic reprogramming of HSCs through the toll-like receptor 3/cyclooxygenase-2/cyclooxygenase-2 pathway. Therefore, NET inhibition may represent an attractive treatment target for MASH liver fibrosis.

Metabolic Dysfunction Associated Steatotic Liver Disease (MASLD) and its progressive form, Metabolic Dysfunction Associated Steatohepatitis (MASH), represent significant health concerns associated with the metabolic syndrome. These conditions are characterized by excessive hepatic fat accumulation, inflammation, and potential progression to cirrhosis and hepatocellular carcinoma. Neutrophils are innate immune cells that play a pivotal role in the development of MASLD and MASH. They can infiltrate the hepatic microenvironment in response to inflammatory cytokines and damage associated molecular patterns (DAMPs) derived from the liver and exacerbate tissue damage by releasing of reactive oxygen species (ROS), cytokines, and neutrophil extracellular traps (NETs). Moreover, neutrophils can disrupt the metabolism of hepatocytes through key factors such as neutrophil elastase (NE) and human neutrophil peptides-1 (HNP-1), leading to inflammation and fibrosis, while myeloperoxidase (MPO) and lipocalin (LCN2) are involved in inflammatory and fibrotic processes. In contrast, neutrophils contribute to liver protection and repair through mechanisms involving microRNA-223 and matrix metalloproteinase 9 (MMP9). This dual role of neutrophils highlights their significance in the pathogenesis of MASLD and MASH. This review summarizes current understanding from recent studies on the involvement of neutrophils in MASLD and MASH. Understanding complex roles of neutrophils within the liver's unique microenvironment offers insights into novel therapeutic strategies, emphasizing the need for further research to explore neutrophil-targeted interventions for managing MASLD and MASH. [BMB Reports 2025; 58(3): 116-123].

Over the last four decades, clinical research and experimental studies have established that lipopolysaccharide (LPS)-a component of the outer membrane of gram-negative bacteria-is a potent hepatotoxic molecule in humans and animals. Alcohol abuse is commonly associated with LPS endotoxemia. This review highlights LPS molecular structures and modes of release from bacteria, plasma LPS concentrations, induction of microbiota dysbiosis, disruption of gut epithelial barrier, and translocation of LPS into the portal circulation impacting the pathophysiology of hepatic cells via the gut-liver axis. We describe and illustrate the portal vein circulation and its distributaries draining the gastrointestinal tract. We also elaborate on the gut-liver axis coupled with enterohepatic circulation that represents a bidirectional communication between the gut and liver. The review also updates the data on how circulating LPS is cleared in a coordinated effort between Kupffer cells, hepatocytes, and liver sinusoidal endothelial cells. Significantly, the article reviews and updates the modes/mechanisms of action by which LPS mediates the diverse pathophysiology of Kupffer cells, hepatocytes, sinusoidal endothelial cells, and hepatic stellate cells primarily in association with alcohol consumption. Specifically, we review the intricate linkages between ethanol, microbiota dysbiosis, LPS production, gut-liver axis, and pathophysiology of various hepatic cells. The maintenance of the gut barrier structural and functional integrity and microbiome homeostasis is essential in mitigating alcoholic liver disease and improving liver health.

Alcohol-related liver disease (ALD) is a leading cause of chronic liver conditions globally. Chronic alcohol consumption induces liver damage through various mechanisms, including neutrophil extracellular trap (NET) formation. Extracellular DNA (ecDNA), released from damaged hepatocytes and NETotic neutrophils, has emerged as a potential biomarker and contributor to liver disease pathology. Enzyme DNases could be an effective therapy for the denaturation of immunogenic ecDNA. This study investigated the circulating ecDNA and NET markers in ALD and therapeutic effect of DNase I in a murine model of ALD. Female C57BL/6J mice were fed a control diet (n = 13) or Lieber-DeCarli ethanol diet for 10 days followed by a binge ethanol dose to mimic acute-on-chronic alcoholic liver injury. From day 5, mice fed ethanol were randomized into an ethanol diet group (n = 17) and ethanol + DNase group (n = 5), which received additional DNase I treatment every 12 h. Liver damage markers were analyzed. Circulating ecDNA and NETosis were measured by fluorometry and cytometry, respectively. DNase I activity was analyzed with single radial enzyme dispersion assay. The ethanol-fed mice exhibited increased mortality, neutrophil infiltration and structural damage in the liver. Total circulating ecDNA levels and NET markers did not differ between groups. DNase activity was higher in ethanol-fed mice compared to controls and additional daily administration of DNase prevented liver injury. These findings suggest that alcohol-induced liver injury modestly influences systemic NETosis and ecDNA levels. However, increased DNase activity can prevent disease progression and enhanced systemic degradation of ecDNA using DNase I.

Metabolic dysfunction-associated steatohepatitis (MASH) has become a serious threat to human health, which exhibited an increasing prevalence globally. Recently, the farnesoid X receptor (FXR) has been identified as a promising strategy for the treatment of MASH by regulating multiple pathogenesis. In this study, a new series of FXR agonists bearing piperidine scaffold was designed to reduce the high lipophilicity of the existing FXR agonists. After comprehensive multiparameter optimization, LZ-007 was discovered as a highly potent FXR agonist with suitable stability in liver microsomes of multiple species. LZ-007 exhibited highly oral bioavailability and targeted tissue exposure in the liver and ileum, while the plasma exposure is low, which might minimize the systemic side effects. Moreover, LZ-007 was significantly up-regulated the expressions of FXR and its downstream genes in the liver and ileum. In MASH model, LZ-007 exerted potent anti-MASH effects by regulating the multiple signal pathways related to lipid metabolism, oxidative stress, inflammation and fibrosis. In a 30-day toxicity study, no apparent adverse effects were observed in LZ-007 treated groups, even at the high doses of 250 and 500 mg/kg. With the positive pharmacodynamics and safety profiles, LZ-007 is worthy of further evaluation as a new anti-MASH agent.

Tumor-associated neutrophils (TANs) are heterogeneous; thus, their roles in tumor development could vary depending on the cancer type. Here, we showed that TANs affect metabolic dysfunction-associated steatohepatitis hepatocellular carcinoma (MASH-related HCC) more than viral-associated HCC. We attributed this difference to the predominance of SiglecFhi TANs in MASH-related HCC tumors. Linoleic acid and GM-CSF, which are commonly elevated in the MASH-related HCC microenvironment, fostered the development of this c-Myc-driven TAN subset. Through TGFβ secretion, SiglecFhi TANs promoted HCC stemness, proliferation, and migration. Importantly, SiglecFhi TANs supported immune evasion by directly suppressing the antigen presentation machinery of tumor cells. SiglecFhi TAN removal increased the immunogenicity of a MASH-related HCC model and sensitized it to immunotherapy. Likewise, a high SiglecFhi TAN signature was associated with poor prognosis and immunotherapy resistance in HCC patients. Overall, our study highlights the importance of understanding TAN heterogeneity in cancer to improve therapeutic development.

Alcoholic liver disease (ALD) and non-alcoholic fatty liver disease (NAFLD) are two major chronic liver diseases worldwide. The triggers for fatty liver can be derived from external sources such as adipose tissue, the gut, personal diet, and genetics, or internal sources, including immune cell responses, lipotoxicity, hepatocyte death, mitochondrial dysfunction, and extracellular vesicles. However, their pathogenesis varies to some extent. This review summarizes various immune mechanisms and therapeutic targets associated with these two types of fatty liver disease. It describes the gut-liver axis and adipose tissue-liver crosstalk, as well as the roles of different immune cells (both innate and adaptive immune cells) in fatty liver disease. Additionally, mitochondrial dysfunction, extracellular vesicles, microRNAs (miRNAs), and gastrointestinal hormones are also related to the pathogenesis of fatty liver. Understanding the pathogenesis of fatty liver and corresponding therapeutic strategies provides a new perspective for developing novel treatments for fatty liver disease.

Cancer frequently causes venous thromboembolism (VTE), a leading cause of cancer-related mortality. Primary liver cancer (PLC) is prevalent and highly fatal, with an increased risk of venous thrombotic complications. Thus, we aimed to develop a nomogram model for predicting VTE in patients with PLC. We retrospectively analyzed 1,565 patients diagnosed with PLC between January 2018 and December 2022 at Chongqing University Cancer Hospital. Univariate logistic analysis and multivariate logistic regression identified eight significant risk factors: activated partial thromboplastin time (APTT) ≤ 32.20 s, D-dimer > 1.44 mg/L, lymphocyte count (LYM) ≤ 1.18 × 109/L, monocyte count (MONO) > 0.42 × 109/L, transarterial chemoembolization (TACE), surgical intervention, immunotherapy, and β2-microglobulin. The nomogram model exhibited strong discriminatory power, with C indices of 0.753 and 0.710 for the training and validation cohorts, respectively. The calibration curve showed a strong correlation between predicted and actual probabilities. Additionally, decision curve analysis (DCA) and clinical impact curves (CIC) confirmed the model's clinical utility. This nomogram facilitates the identification of high-risk PLC patients, allowing for timely preventive and therapeutic interventions to reduce the risk of thrombosis.

A slew of common metabolic disorders, including type 2 diabetes, metabolic dysfunction-associated steatotic liver disease and steatohepatitis, are exponentially increasing in our sedentary and overfed society. While macronutrients directly impact metabolism and bioenergetics, new evidence implicates immune cells as critical sensors of nutritional cues and important regulators of metabolic homeostasis. A deeper interrogation of the intricate and multipartite interactions between dietary components, immune cells and metabolically active tissues is needed for a better understanding of metabolic regulation and development of new treatments for common metabolic diseases. Responding to macronutrients and micronutrients, immune cells play pivotal roles in interorgan communication between the microbiota, small intestine, metabolically active cells including hepatocytes and adipocytes, and the brain, which controls feeding behavior and energy expenditure. This Review focuses on the response of myeloid cells and innate lymphocytes to dietary cues, their cross-regulatory interactions and roles in normal and aberrant metabolic control.

Neutrophils are the most abundant cell type in human blood and play a crucial role in the immune system and development of tumors. This review begins with the generation and development of neutrophils, traces their release from the bone marrow into the bloodstream, and finally discusses their role in the hepatocellular carcinoma (HCC) microenvironment. It elaborates in detail the mechanisms by which tumor-associated neutrophils (TANs) exert antitumor or protumor effects under the influence of various mediators in the tumor microenvironment. Neutrophils can exert antitumor effects through direct cytotoxic action. However, they can also accelerate the formation and progression of HCC by being recruited and infiltrated, promoting tumor angiogenesis, and maintaining an immunosuppressive microenvironment. Therefore, based on the heterogeneity and plasticity of neutrophils in tumor development, this review summarizes the current immunotherapies targeting TANs, discusses potential opportunities and challenges, and provides new insights into exploring more promising strategies for treating HCC.

Chronic inflammation is a common characteristic of all kinds of diseases, including autoimmune diseases, metabolic diseases, and tumors. It is distinguished by the presence of low concentrations of inflammatory factors stimulating the body for an extended period, resulting in a persistent state of infection. This condition is manifested by the aggregation and infiltration of mononuclear cells, lymphocytes, and other immune cells, leading to tissue hyperplasia and lesions. Although various anti-inflammatory medications, including glucocorticoids and non-steroidal anti-inflammatory drugs (NSAIDs), have shown strong therapeutic effects, they lack specificity and targeting ability, and require high dosages, which can lead to severe adverse reactions. Nanoparticle drug delivery mechanisms possess the capacity to minimize the effect on healthy cells or tissues due to their targeting capabilities and sustained drug release properties. However, most nanosystems can only target the inflammatory sites rather than specific types of immune cells, leaving room for further improvement in the therapeutic effects of nanomaterials. This article reviews the current research progress on the role of diverse immune cells in inflammation, focusing on the functions of neutrophils and macrophages during inflammation. It provides an overview of the domestic and international applications of nanomaterials in targeted therapy for inflammation, aiming to establish a conceptual foundation for the utilization of nanomaterials targeting immune cells in the treatment of chronic inflammation and offer new perspectives for the avoidance and management of inflammation.

Liver cancer remains one of the most formidable challenges in modern medicine, characterized by its high incidence and mortality rate. Emerging evidence underscores the critical roles of the immune microenvironment in tumor initiation, development, prognosis, and therapeutic responsiveness. However, the composition of the immune microenvironment of liver cancer (LC-IME) and its association with clinicopathological significance remain unelucidated. In this review, we present the recent developments related to the use of artificial intelligence (AI) for studying the immune microenvironment of liver cancer, focusing on the deciphering of complex high-throughput data. Additionally, we discussed the current challenges of data harmonization and algorithm interpretability for studying LC-IME.

Obesity is a chronic, multifactorial disease characterized by persistent low-grade tissue and systemic inflammation. Fat accumulation in adipose tissue (AT) leads to stress and dysfunctional adipocytes, along with the infiltration of immune cells, which initiates and sustains inflammation. Neutrophils are the first immune cells to infiltrate AT during high-fat diet (HFD)-induced obesity. Emerging evidence suggests that the formation and release of neutrophil extracellular traps (NETs) play a significant role in the progression of obesity and related diseases. Additionally, obesity is associated with an imbalance in gut microbiota and increased intestinal barrier permeability, resulting in the translocation of live bacteria, bacterial deoxyribonucleic acid (DNA), lipopolysaccharides (LPS), and pro-inflammatory cytokines into the bloodstream and AT, thereby contributing to metabolic inflammation. Recent research has also shown that short-chain fatty acids (SCFAs), produced by gut microbiota, can influence various functions of neutrophils, including their activation, migration, and the generation of inflammatory mediators. This review comprehensively summarizes recent advancements in understanding the role of neutrophils and NET formation in the pathophysiology of obesity and related disorders while also focusing on updated potential therapeutic approaches targeting NETs based on studies conducted in humans and animal models.

Neutrophil extracellular traps (NETs) are network-like structures released by activated neutrophils. They consist mainly of double-stranded DNA, histones, and neutrophil granule proteins. Continuous release of NETs in response to external stimuli leads to activation of surrounding platelets and monocytes/macrophages, resulting in damage to endothelial cells (EC) and vascular smooth muscle cells (VSMC). Some clinical trials have demonstrated the association between NETs and the severity and prognosis of atherosclerosis. Furthermore, experimental findings have shed light on the molecular mechanisms by which NETs contribute to atherogenesis. NETs play a significant role in the formation of atherosclerotic plaques. This review focuses on recent advancements in the understanding of the relationship between NETs and atherosclerosis. It explores various aspects, including the formation of NETs in atherosclerosis, clinical trials investigating NET-induced atherosclerosis, the mechanisms by which NETs promote atherogenesis, and the translational implications of NETs. Ultimately, we aim to propose new research directions for the diagnosis and treatment of atherosclerosis.

Endothelial dysfunction (ED) is the in the background of multiple metabolic diseases and a key process in liver disease progression and cirrhosis decompensation. ED affects liver sinusoidal endothelial cells (LSECs) in response to different damaging agents, causing their progressive dedifferentiation, unavoidably associated with an increase in intrahepatic resistance that leads to portal hypertension and hyperdynamic circulation with increased cardiac output and low peripheral artery resistance. These changes are driven by a continuous interplay between different hepatic cell types, invariably leading to increased reactive oxygen species (ROS) formation, increased release of pro-inflammatory cytokines and chemokines, and reduced nitric oxide (NO) bioavailability, with a subsequent loss of proper vascular tone regulation and fibrosis development. ED evaluation is often accomplished by serum markers and the flow-mediated dilation (FMD) measurement of the brachial artery to assess its NO-dependent response to shear stress, which usually decreases in ED. In the context of liver cirrhosis, the ED assessment could help understand the complex hemodynamic changes occurring in the early and late stages of the disease. However, the instauration of a hyperdynamic state and the different NO bioavailability in intrahepatic and systemic circulation-often defined as the NO paradox-must be considered confounding factors during FMD analysis. The primary purpose of this review is to describe the main features of ED and highlight the key findings of the dynamic and intriguing relationship between ED and liver disease. We will also focus on the significance of FMD evaluation in this setting, pointing out its key role as a therapeutic target in the never-ending battle against liver cirrhosis progression.

Absent in melanoma 2 (AIM2) inflammasome-dependent pyroptosis and neutrophil extracellular traps (NETs) have been implicated in chronic liver disease (CLD). However, the specific intrahepatic cell type that undergoes AIM2 inflammasome-dependent pyroptosis and how their interaction augments hepatic inflammation/fibrosis remains unclear.

The expression and correlation of AIM2 inflammasome-dependent pyroptosis-related indicators and NETs were analyzed in biopsy tissue and blood specimens from chronic hepatitis patients (CHs). Cell-based experiments were conducted to investigate their interaction. In vitro and in vivo experiments were used to analyze their effects on the progression of hepatic inflammation/fibrosis as well as their clinical importance.

Elevated levels of AIM2 inflammasome-dependent pyroptosis indicators and NETs were detected in biopsy tissue and blood specimens. Circulating NETs were positively correlated with pyroptosis-related indicators, and both were related with disease severity. Confocal imaging revealed that AIM2 was mainly localized to hepatic macrophages, indicating that hepatic macrophages were the major cell type that underwent pyroptosis. NETs were directly engulfed by macrophages and then stimulated AIM2 inflammasome-dependent macrophage pyroptosis in vitro, which amplified the activation of hepatic stellate cells (HSCs) and increased collagen deposition. Administration of the NETs degradation agent DNase I or the AIM2 inflammasome activation inhibitor ODN A151 effectively alleviated chronic liver inflammation/fibrosis progression in vivo.

NETs-induced AIM2 inflammasome-dependent pyroptosis in macrophages facilitates liver inflammation/fibrosis progression. The identified NET-AIM2 inflammasome cascade could serve as a novel therapeutic target for hepatic inflammation/fibrosis progression.

Dysregulated metabolism, cell death, and inflammation contribute to the development of metabolic dysfunction-associated steatohepatitis (MASH). Pyroptosis, a recently identified form of programmed cell death, is closely linked to inflammation. However, the precise role of pyroptosis, particularly gasdermin-E (GSDME), in MASH development remains unknown. In this study, we observed GSDME cleavage and GSDME-associated interleukin-1β (IL-1β)/IL-18 induction in liver tissues of MASH patients and MASH mouse models induced by a choline-deficient high-fat diet (CDHFD) or a high-fat/high-cholesterol diet (HFHC). Compared with wild-type mice, global GSDME knockout mice exhibited reduced liver steatosis, steatohepatitis, fibrosis, endoplasmic reticulum stress, lipotoxicity and mitochondrial dysfunction in CDHFD- or HFHC-induced MASH models. Moreover, GSDME knockout resulted in increased energy expenditure, inhibited intestinal nutrient absorption, and reduced body weight. In the mice with GSDME deficiency, reintroduction of GSDME in myeloid cells-rather than hepatocytes-mimicked the MASH pathologies and metabolic dysfunctions, as well as the changes in the formation of neutrophil extracellular traps and hepatic macrophage/monocyte subclusters. These subclusters included shifts in Tim4+ or CD163+ resident Kupffer cells, Ly6Chi pro-inflammatory monocytes, and Ly6CloCCR2loCX3CR1hi patrolling monocytes. Integrated analyses of RNA sequencing and quantitative proteomics revealed a significant GSDME-dependent reduction in citrullination at the arginine-114 (R114) site of dynamin-related protein 1 (Drp1) during MASH. Mutation of Drp1 at R114 reduced its stability, impaired its ability to redistribute to mitochondria and regulate mitophagy, and ultimately promoted its degradation under MASH stress. GSDME deficiency reversed the de-citrullination of Drp1R114, preserved Drp1 stability, and enhanced mitochondrial function. Our study highlights the role of GSDME in promoting MASH through regulating pyroptosis, Drp1 citrullination-dependent mitochondrial function, and energy balance in the intestine and liver, and suggests that GSDME may be a potential therapeutic target for managing MASH.

The role of Neutrophil extracellular traps (NETs) in the immunopathogenesis of Diabetic Kidney Disease (DKD) remains elusive. We used a machine learning approach to identify differentially expressed genes (DEGs) associated with NETs in human DKD kidney biopsy datasets and validated the results using single-nucleus RNA sequencing datasets. The expressions of these candidate genes and related cytokines were verified in blood obtained from DKD patients. Three NETs-associated genes (ITGAM, ITGB2 and TLR7) were identified, which all showed significant upregulation in both glomerular and tubulointerstitial compartments in human DKD kidneys. DKD patients showed significantly higher number of activated neutrophils with increased ITGAM and ITGB2 expression, higher serum IL-6 but lower IL-10, compared to healthy controls (p all <0.01). This study suggests that dysregulation of NETs-associated genes ITGAM and ITGB2 are related to the pathogenesis of DKD, and may serve as novel diagnostic markers and therapeutic targets in DKD.

Cancer and metabolic disorders have emerged as major global health challenges, reaching epidemic levels in recent decades. Often viewed as separate issues, metabolic disorders are shown by mounting evidence to heighten cancer risk and incidence. The intricacies underlying this connection are still being unraveled and encompass a complex interplay between metabolites, cancer cells and immune cells within the tumour microenvironment (TME). Here, we outline the interplay between metabolic and immune cell dysfunction in the context of three highly prevalent metabolic disorders, namely obesity; two associated liver diseases, metabolic dysfunction-associated steatotic liver disease (MASLD) and metabolic dysfunction-associated steatohepatitis (MASH); and type 2 diabetes. We focus primarily on macrophages and T cells, the critical roles of which in dictating inflammatory response and immune surveillance in metabolic disorder-associated cancers are widely reported. Moreover, considering the ever-increasing number of patients prescribed with metabolism disorder-altering drugs and diets in recent years, we discuss how these therapies modulate systemic and local immune phenotypes, consequently impacting cancer malignancy. Collectively, unraveling the determinants of metabolic disorder-associated immune landscape and their role in fuelling cancer malignancy will provide a framework essential to therapeutically address these highly prevalent diseases.

The close association between inflammation and the clinical outcomes of hepatocellular carcinoma (HCC) has been extensively documented. This study aims to analyze the association between a novel inflammatory indicator, the gamma-glutamyl transpeptidase to neutrophil ratio (GNR), and HCC prognosis following curative resection.

A cohort of 204 eligible HCC cases were included. Based on an optimal cut-off value determined utilizing the X-tile software, patients were categorized into low- and high-GNR groups. The overall survival (OS) and recurrence-free survival (RFS) rates were assessed using the Kaplan-Meier analysis method with Log rank tests. Multivariate Cox proportional hazard regression was used to investigate the independent association between GNR and HCC prognosis. Restricted cubic splines were used to explore the nonlinear relationship between GNR and the risk of death or recurrence.

The low GNR group exhibited significantly higher 3-year OS and RFS rates than the high GNR group. Multivariate Cox analysis indicated that a high GNR level was independently associated with poor OS and RFS. A linear correlation between GNR and the risk of death, as well as a nonlinear inverted "U" shape correlation between GNR and the risk of recurrence, were observed.

The findings provide evidence supporting the independent association of GNR with HCC prognosis. These results offer promise for enhancing prognosis assessments and guiding active monitoring strategies for patients with HCC post-curative resection.

The tumor microenvironment (TME) is intricately associated with cancer progression, characterized by dynamic interactions among various cellular and molecular components that significantly impact the carcinogenic process. Notably, neutrophils play a crucial dual role in regulating this complex environment. These cells oscillate between promoting and inhibiting tumor activity, responding to a multitude of cytokines, chemokines, and tumor-derived factors. This response modulates immune reactions and affects the proliferation, metastasis, and angiogenesis of cancer cells. A significant aspect of their influence is their interaction with the endoplasmic reticulum (ER) stress responses in cancer cells, markedly altering tumor immunodynamics by modulating the phenotypic plasticity and functionality of neutrophils. Furthermore, neutrophil extracellular traps (NETs) exert a pivotal influence in the progression of malignancies by enhancing inflammation, metastasis, immune suppression, and thrombosis, thereby exacerbating the disease. In the realm of immunotherapy, checkpoint inhibitors targeting PD-L1/PD-1 and CTLA-4 among others have underscored the significant role of neutrophils in enhancing therapeutic responses. Recent research has highlighted the potential of using neutrophils for targeted drug delivery through nanoparticle systems, which precisely control drug release and significantly enhance antitumor efficacy. This review thoroughly examines the diverse functions of neutrophils in cancer treatment, emphasizing their potential in regulating immune therapy responses and as drug delivery carriers, offering innovative perspectives and profound implications for the development of targeted diagnostic and therapeutic strategies in oncology.

Non-alcoholic fatty liver disease, recently renamed metabolic dysfunction-associated steatotic liver disease (MASLD), is a complex multifactorial disease that progresses from steatohepatitis (MASH) to liver cirrhosis and liver cancer. Recent research has revealed that crosstalk between innate immune cells and hepatic parenchymal and non-parenchymal cells is involved in the pathogenesis of liver disease in MASLD/MASH. Of particular importance, novel inflammatory mechanisms, including macrophage diversity, neutrophil NETosis, B-cell biology, auto-reactive T cells, unconventional T cells, and dendritic cell-T cell interactions, are considered key drivers for disease progression. These mechanisms and factors are potential targets for the therapeutic intervention of MASLD/MASH. In this review, we focus on recent discoveries related to liver inflammation and discuss the role of innate immune cell subsets in MASLD/MASH.

Alcohol use in metabolic dysfunction-associated steatohepatitis (MASH) is associated with an increased risk of fibrosis and liver-related death. Here, we aimed to identify a mechanism through which repeated alcohol binges exacerbate liver injury in a high fat-cholesterol-sugar diet (MASH diet)-induced model of MASH.

C57BL/6 mice received either chow or the MASH diet for 3 months with or without weekly alcohol binges. Neutrophil infiltration, neutrophil extracellular traps (NETs) and fibrosis were evaluated.

We found that alcohol binges in MASH increase liver injury and fibrosis. Liver transcriptomic profiling revealed differential expression of genes involved in extracellular matrix reorganisation, neutrophil activation and inflammation compared with alcohol or the MASH diet alone. Alcohol binges specifically increased NET formation in MASH livers in mice, and NETs were also increased in human livers with MASH plus alcohol use. We discovered that cell-free NETs are sensed via Nod-like receptor protein 3 (NLRP3). Furthermore, we show that cell-free NETs in vitro induce a profibrotic phenotype in hepatic stellate cells (HSCs) and proinflammatory monocytes. In vivo, neutrophil depletion using anti-Ly6G antibody or NET disruption with deoxyribonuclease treatment abrogated monocyte and HSC activation and ameliorated liver damage and fibrosis. In vivo, inhibition of NLRP3 using MCC950 or NLRP3 deficiency attenuated NET formation, liver injury and fibrosis in MASH plus alcohol diet-fed mice (graphical abstract).

Alcohol binges promote liver fibrosis via NET-induced activation of HSCs and monocytes in MASH. Our study highlights the potential of inhibition of NETs and/or NLRP3, as novel therapeutic strategies to combat the profibrotic effects of alcohol in MASH.

Since differentiating malignant ascites from benign ascites has always been a clinical difficult, recognition of novel biomarkers in malignant ascites of hepatocellular carcinoma (HCC) patients could be helpful for establishing a diagnosis for HCC patients with ascitic fluids.

Thirty-five HCC patients with malignant ascites and chronic liver diseases patients with benign ascites were enrolled. Serum and ascites specimens were collected to determine TAN subpopulations and NETs concentration. Then, the correlation between ascitic NETs levels and clinical features were analyzed, and ROC curves were generated to evaluate the diagnostic value of NETs. For in vitro study, fresh neutrophils were employed to explore the underlying mechanism of TAN polarization and NETs formation using RNAseq analysis.

Significantly increased pro-tumor PD-L1+ TANs and higher lactate levels were measured in HCC ascites. RNAseq data showed that lactate regulated genes expression involving PD-L1 expression and NETs formation, suggesting that ascitic lactate might be responsible for tumor progression in TME. Then, NETs-related markers including calprotectin, dsDNA, CitH3, MPO and MPO-DNA were found dramatically elevated in malignant ascites. Next, correlation analysis revealed that ascitic NETs levels positively correlated with LDH, a classic ascitic biochemical indicator. Furthermore, we identified the diagnostic values of NETs in discriminating malignant ascites from benign ascites.

Our findings highlighted that elevated ascitic NETs served as a biomarker in HCC patients with malignant ascites, which provided useful insights for both clinical and basic research for malignant ascites diagnosis and management.

Steatotic liver diseases (SLD) are the principal worldwide cause of cirrhosis and end-stage liver cancer, affecting nearly a quarter of the global population. SLD includes metabolic dysfunction-associated alcoholic liver disease (MetALD) and metabolic dysfunction-associated steatotic liver disease (MASLD), resulting in asymptomatic liver steatosis, fibrosis, cirrhosis and associated complications. The immune processes include gut dysbiosis, adiposeliver organ crosstalk, hepatocyte death and immune cell-mediated inflammatory processes. Notably, various immune cells such as B cells, plasma cells, dendritic cells, conventional CD4+ and CD8+ T cells, innate-like T cells, platelets, neutrophils and macrophages play vital roles in the development of MetALD and MASLD. Immunological modulations targeting hepatocyte death, inflammatory reactions and gut microbiome include N-acetylcysteine, selonsertib, F-652, prednisone, pentoxifylline, anakinra, JKB-121, HA35, obeticholic acid, probiotics, prebiotics, antibiotics and fecal microbiota transplantation. Understanding the immunological mechanisms underlying SLD is crucial for advancing clinical therapeutic strategies.

Acute liver failure (ALF) is an acute liver disease with a high mortality rate in clinical practice, characterized histologically by extensive hepatocellular necrosis and massive neutrophil infiltration. However, the role of these abnormally infiltrating neutrophils during ALF development is unclear. Here, in an ALF mouse model, metabolites were identified that promote the formation of neutrophil extracellular traps (NETs) in the liver, subsequently influencing macrophage differentiation and disease progression. ALF occurs with abnormalities in hepatic and intestinal metabolites. Abnormal metabolites (LTD4 and glutathione) can directly, or indirectly via reactive oxygen species, promote NET formation of infiltrating neutrophils, which subsequently regulate macrophages in a pro-inflammatory M1-like state, inducing an amplification of the destructive effects of inflammation. Together, this study provides new insights into the role of NETs in the pathogenesis of ALF.

Hepatocellular carcinoma (HCC) represents the sixth most diagnosed cancer worldwide and is the second leading cause of cancer-related death in the world. The association of HCC and portal vein thrombosis (PVT) represents an advanced stage of the tumor. PVT has a prevalence of about 25-50% in HCC, determining poor prognosis and a remarkable reduction in therapeutic perspectives in these patients, leading to severe complications such as ascites, metastasis, an increase in portal hypertension and potentially fatal gastrointestinal bleeding. The aim of this review is to evaluate the molecular mechanisms that are at the basis of PVT development, trying to evaluate possible strategies in the early detection of patients at high risk of PVT.

Neutrophil extracellular traps (NETs), crucial in immune defense mechanisms, are renowned for their propensity to expel decondensed chromatin embedded with inflammatory proteins. Our comprehension of NETs in pathogen clearance, immune regulation and disease pathogenesis, has grown significantly in recent years. NETs are not only pivotal in the context of infections but also exhibit significant involvement in sterile inflammation. Evidence suggests that excessive accumulation of NETs can result in vessel occlusion, tissue damage, and prolonged inflammatory responses, thereby contributing to the progression and exacerbation of various pathological states. Nevertheless, NETs exhibit dual functionalities in certain pathological contexts. While NETs may act as autoantigens, aggregated NET complexes can function as inflammatory mediators by degrading proinflammatory cytokines and chemokines. The delineation of molecules and signaling pathways governing NET formation aids in refining our appreciation of NETs' role in immune homeostasis, inflammation, autoimmune diseases, metabolic dysregulation, and cancer. In this comprehensive review, we delve into the multifaceted roles of NETs in both homeostasis and disease, whilst discussing their potential as therapeutic targets. Our aim is to enhance the understanding of the intricate functions of NETs across the spectrum from physiology to pathology.