Different minimal alcohol consumption in male and female individuals with metabolic dysfunction-associated fatty liver disease.

BACKGROUND AND AIMS: The relationship between moderate alcohol intake and health outcomes among individuals with metabolic dysfunction-associated fatty liver disease (MAFLD) is complex. Our aim was to investigate the association of minimal alcohol consumption with all-cause and cause-specific mortality among MAFLD individuals of different genders. METHODS: Our study included 2630 MAFLD individuals from the Third National Health and Nutrition Examination Survey. Cox regression analysis was performed to assess the association between alcohol use measures and all-cause and cause-specific mortality. Restricted cubic spline curves were used to evaluate the relationship between alcohol consumption per week and all-cause mortality. RESULTS: In the entire MAFLD cohort, we observed significant disparities in clinical characteristics between male and female individuals with MAFLD. Higher weekly alcohol consumption was significantly associated with all-cause and cause-specific mortality (male, hazard ratios [HRs]: 1.009, 95% CIs: 1.004-1.014; female, HRs: 1.032, 95% CIs: 1.022-1.042). In males with MAFLD, a linear association with all-cause mortality was observed for weekly alcohol consumption (p for non-linearity = .21). Conversely, in females with MAFLD, the risk of all-cause mortality remained relatively stable until 2 drinks per week, after which it rapidly increased with each additional drink consumed, and the increase in mortality risk was higher than that observed in males (p for non-linearity < .05). CONCLUSIONS: Our findings indicate that any increase in weekly alcohol consumption was associated with increased all-cause mortality in men with MAFLD. Conversely, consuming less than 2 drinks per week had minimal impact on the risk of mortality among female.

Histone methyltransferase Suv39h1 regulates hepatic stellate cell activation and is targetable in liver fibrosis.

OBJECTIVE: Liver fibrosis is a prelude to a host of end-stage liver diseases. Hepatic stellate cells (HSCs), switching from a quiescent state to myofibroblasts, are the major source for excessive production of extracellular matrix proteins. In the present study, we investigated the role of Suv39h1, a lysine methyltransferase, in HSC-myofibroblast transition and the implication in liver fibrosis. DESIGN: HSC-specific or myofibroblast-specific Suv39h1 deletion was achieved by crossbreeding the Suv39h1 f/f mice to the Lrat-Cre mice or the Postn-CreERT2 mice. Liver fibrosis was induced by CCl4 injection or bile duct ligation. RESULTS: We report that Suv39h1 expression was universally upregulated during HSC-myofibroblast transition in different cell and animal models of liver fibrosis and in human cirrhotic liver tissues. Consistently, Suv39h1 knockdown blocked HSC-myofibroblast transition in vitro. HSC-specific or myofibroblast-specific deletion of Suv39h1 ameliorated liver fibrosis in mice. More importantly, Suv39h1 inhibition by a small-molecule compound chaetocin dampened HSC-myofibroblast transition in cell culture and mitigated liver fibrosis in mice. Mechanistically, Suv39h1 bound to the promoter of heme oxygenase 1 (HMOX1) and repressed HMOX1 transcription. HMOX1 depletion blunted the effects of Suv39h1 inhibition on HSC-myofibroblast transition in vitro and liver fibrosis in vivo. Transcriptomic analysis revealed that HMOX1 might contribute to HSC-myofibroblast transition by modulating retinol homeostasis. Finally, myofibroblast-specific HMOX1 overexpression attenuated liver fibrosis in both a preventive scheme and a therapeutic scheme. CONCLUSIONS: Our data demonstrate a previously unrecognised role for Suv39h1 in liver fibrosis and offer proof-of-concept of its targetability in the intervention of cirrhosis.

The impact of an increased Fibrosis-4 index and the severity of hepatic steatosis on mortality in individuals living with diabetes.

BACKGROUND AND AIMS: Data on the effects of liver fibrosis and hepatic steatosis on outcomes in individuals living with diabetes are limited. Therefore, we investigated the predictive value of the fibrosis and the severity of hepatic steatosis for all-cause mortality in individuals living with diabetes. METHODS: A total of 1903 patients with diabetes from the Third National Health and Nutrition Examination Survey (NHANES III) dataset were enrolled. Presumed hepatic fibrosis was evaluated with Fibrosis-4 index (FIB-4). The mortality risk and corresponding hazard ratio (HR) were analyzed with the Kaplan-Meier method and multivariable Cox proportional hazard models. RESULTS: Over a median follow-up of 19.4 years, all-cause deaths occurred in 69.6%. FIB-4 ≥ 1.3 was an independent predictor of mortality in individuals living with diabetes (HR 1.219, 95% confidence interval [CI]: 1.067-1.392, p = 0.004). Overall, FIB-4 ≥ 1.3 without moderate-severe steatosis increased the mortality risk (HR 1.365; 95%CI 1.147-1.623, p < 0.001). The similar results were found in individuals living with diabetes with metabolic dysfunction-associated fatty liver disease (MAFLD) (HR 1.499; 95%CI 1.065-2.110, p = 0.020), metabolic syndrome (MetS) (HR 1.397; 95%CI 1.086-1.796, p = 0.009) or abdominal obesity (HR 1.370; 95%CI 1.077-1.742, p = 0.010). CONCLUSIONS: Liver fibrosis, as estimated by FIB-4, may serve as a more reliable prognostic indicator for individuals living with diabetes than hepatic steatosis. Individuals living with diabetes with FIB-4 ≥ 1.3 without moderate-severe steatosis had a significantly increased all-cause mortality risk. These findings highlight the importance of identifying and monitoring those individuals, as they may benefit from further evaluation and risk stratification.

Development of a machine learning-based model to predict hepatic inflammation in chronic hepatitis B patients with concurrent hepatic steatosis: a cohort study.

Background: With increasingly prevalent coexistence of chronic hepatitis B (CHB) and hepatic steatosis (HS), simple, non-invasive diagnostic methods to accurately assess the severity of hepatic inflammation are needed. We aimed to build a machine learning (ML) based model to detect hepatic inflammation in patients with CHB and concurrent HS. Methods: We conducted a multicenter, retrospective cohort study in China. Treatment-naive CHB patients with biopsy-proven HS between April 2004 and September 2022 were included. The optimal features for model development were selected by SHapley Additive explanations, and an ML algorithm with the best accuracy to diagnose moderate to severe hepatic inflammation (Scheuer's system ≥ G3) was determined and assessed by decision curve analysis (DCA) and calibration curve. This study is registered with ClinicalTrials.gov (NCT05766449). Findings: From a pool of 1,787 treatment-naive patients with CHB and HS across eleven hospitals, 689 patients from nine of these hospitals were chosen for the development of the diagnostic model. The remaining two hospitals contributed to two independent external validation cohorts, comprising 509 patients in validation cohort 1 and 589 in validation cohort 2. Eleven features regarding inflammation, hepatic and metabolic functions were identified. The gradient boosting classifier (GBC) model showed the best performance in predicting moderate to severe hepatic inflammation, with an area under the receiver operating characteristic curve (AUROC) of 0.86 (95% CI 0.83-0.88) in the training cohort, and 0.89 (95% CI 0.86-0.92), 0.76 (95% CI 0.73-0.80) in the first and second external validation cohorts, respectively. A publicly accessible web tool was generated for the model. Interpretation: Using simple parameters, the GBC model predicted hepatic inflammation in CHB patients with concurrent HS. It holds promise for guiding clinical management and improving patient outcomes. Funding: This research was supported by the National Natural Science Foundation of China (No. 82170609, 81970545), Natural Science Foundation of Shandong Province (Major Project) (No. ZR2020KH006), Natural Science Foundation of Jiangsu Province (No.BK20231118), Tianjin Key Medical Discipline (Specialty), Construction Project, TJYXZDXK-059B, Tianjin Health Science and Technology Project key discipline special, TJWJ2022XK034, and Research project of Chinese traditional medicine and Chinese traditional medicine combined with Western medicine of Tianjin municipal health and Family Planning Commission (2021022).

Phosphatidic acid-enabled MKL1 contributes to liver regeneration: Translational implication in liver failure.

Liver regeneration following injury aids the restoration of liver mass and the recovery of liver function. In the present study we investigated the contribution of megakaryocytic leukemia 1 (MKL1), a transcriptional modulator, to liver regeneration. We report that both MKL1 expression and its nuclear translocation correlated with hepatocyte proliferation in cell and animal models of liver regeneration and in liver failure patients. Mice with MKL1 deletion exhibited defective regenerative response in the liver. Transcriptomic analysis revealed that MKL1 interacted with E2F1 to program pro-regenerative transcription. MAPKAPK2 mediated phosphorylation primed MKL1 for its interaction with E2F1. Of interest, phospholipase d2 promoted MKL1 nuclear accumulation and liver regeneration by catalyzing production of phosphatidic acid (PA). PA administration stimulated hepatocyte proliferation and enhanced survival in a MKL1-dependent manner in a pre-clinical model of liver failure. Finally, PA levels was detected to be positively correlated with expression of pro-regenerative genes and inversely correlated with liver injury in liver failure patients. In conclusion, our data reveal a novel mechanism whereby MKL1 contributes to liver regeneration. Screening for small-molecule compounds boosting MKL1 activity may be considered as a reasonable approach to treat acute liver failure.

Aqueous Sol-Gel Synthesis and Shaping of Covalent Organic Frameworks.

The intrinsic fragility and insoluble nature of covalent organic frameworks (COFs) have strongly impeded their processability for practical applications. Herein, an aqueous-based sol-gel synthetic strategy is reported for the synthesis and shaping of COFs with task-specific applications that satisfy the principles of green chemistry for gram-scale production of crystalline materials. Our successful approach involves three pivotal aspects: the "prodrug mimic" design of water-soluble monomers, the utilization of hydrolyzable bonds, and the manipulation of reaction kinetics. The generality of the method is demonstrated by the successful preparation of representative high-surface area two-dimensional (2D) COFs with several commonly used amines. By virtue of this strategy, a COF colloidal dispersion is achieved and can be formulated into processable fluids, structured films, and COF monoliths. Remarkably, the obtained lightweight (∼0.020 g cm-3) and robust aerogels displayed outstanding adsorption capacity (exceeding 57 times its own weight) toward a variety of organic solvents and exhibited superior thermal insulating properties compared to the widely used sponge and cotton. This work demonstrates a versatile strategy for the synthesis and shaping of processable COF materials in water that will contribute to the development of COF monoliths for advanced applications.

The chromatin remodeling protein BRG1 contributes to liver ischemia-reperfusion injury by regulating NOXA expression.

AIMS: Hepatic ischemia-reperfusion injury (IRI) is a common complication secondary to liver transplantation. Extensive death of hepatocytes, typically in the form of apoptosis, is observed in and contributes to IRI. In the present study we investigated the role of BRG1 (encoded by Smarca4), a chromatin remodeling protein, in the pathogenesis of liver IRI focusing on the transcriptional mechanism and translational potential. METHODS: Smarca4f/f mice were crossed to Alb-Cre mice to generate hepatocytes-specific BRG1 knockout mice (CKO). Alterations in cellular transcriptome were evaluated by RNA-seq. RESULTS: BRG1 expression was up-regulated in liver tissues of mice subjected to I/R and in hepatocytes exposed to hypoxia-reoxygenation (H/R). Compared to wild type (WT) littermates, the BRG1 CKO mice displayed significant amelioration of liver injury following ischemia-reperfusion as evidenced by decreased ALT/AST levels and cell apoptosis. Primary hepatocytes isolated from the CKO mice were protected from H/R-induced apoptosis compared to those from the WT mice. RNA-seq analysis revealed phorbol-12-myristate-13-acetate-induced protein 1 (PMAIP1, also known as NOXA) as a novel target for BRG1. Consistently, NOXA knockdown attenuated liver IRI in mice. More importantly, administration of a small-molecule BRG1 inhibitor (PFI-3) protected the mice from liver IRI. CONCLUSIONS: Our data uncover a pivotal role for BRG1 in liver IRI and suggest that targeting BRG1 with small-molecule inhibitors can be considered as a reasonable therapeutic strategy.

Porous Ionic Network/CNT Composite Separator as a Polysulfide Snaring Shield for High Performance Lithium-Sulfur Battery.

Lithium-sulfur (Li-S) battery features a high theoretical energy density, but the shuttle of soluble polysulfides between the two electrodes often results in a rapid capacity decay. Herein, a straightforward electrostatic adsorption strategy based on a cross-linked polyimidazolium separator as a snaring shield of polysulfides is reported, which suppresses the undesirable migration of polysulfides to the anode. The porous ionic network (PIN)-modified carbon nanotubes (CNTs) are successfully prepared and coated onto a commercial porous polypropylene membrane in a vacuum-filtration step. The favorable affinity of the imidazolium ring toward polysulfide via the polar interaction and the electrostatic effect of ions mitigates the undesirable shuttle of polysulfides in the electrolyte, improving the Li─S battery in terms of rate performance and cycling life. Compared to the reference PIN-free CNT-coated separator, the PIN/CNT-coated one has an increased initial capacity of 1.3 folds (up to 1394.8 mAh g-1 for PIN/CNT/PP-3) at 0.1 C.

Hydrogen-Bonded Organic Framework to Upgrade Cycling Stability and Rate Capability of Li-CO2 Batteries.

Elaborately designed multifunctional electrocatalysts capable of promoting Li+ and CO2 transport are essential for upgrading the cycling stability and rate capability of Li-CO2 batteries. Hydrogen-bonded organic frameworks (HOFs) with open channels and easily functionalized surfaces hold great potential for applications in efficient cathodes of Li-CO2 batteries. Herein, a robust HOFS (HOF-FJU-1) is introduced for the first time as a co-catalyst in the cathode material of Li-CO2 batteries. HOF-FJU-1 with cyano groups located periodically in the pore can induce homogeneous deposition of discharge products and accommodate volumetric expansion of discharge products during cycling. Besides, HOF-FJU-1 enables effective interaction between Ru0 nanoparticles and cyano groups, thus forming efficient and uniform catalytic sites for CRR/CER. Moreover, HOF-FJU-1 with regularly arranged open channels are beneficial for CO2 and Li+ transport, enabling rapid redox kinetic conversion of CO2 . Therefore, the HOF-based Li-CO2 batteries are capable of stable operation at 400 mA g-1 for 1800 h and maintain a low overpotential of 1.96 V even at high current densities up to 5 A g-1 . This work provides valuable guidance for developing multifunctional HOF-based catalysts to upgrade the longevity and rate capability of Li-CO2 batteries.

C-C motif chemokine CCL11 is a novel regulator and a potential therapeutic target in non-alcoholic fatty liver disease.

Background & Aims: Non-alcoholic fatty liver disease (NAFLD) is characterised by accelerated lipid deposition, aberrant inflammation, and excessive extracellular matrix production in the liver. Short of effective intervention, NAFLD can progress to cirrhosis and hepatocellular carcinoma. In the present study we investigated the involvement of the C-C motif ligand 11 (CCL11) in NAFLD pathogenesis. Methods: NAFLD was induced by feeding mice with a high-fat high-carbohydrate diet. CCL11 targeting was achieved by genetic deletion or pharmaceutical inhibition. The transcriptome was analysed using RNA-seq. Results: We report that CCL11 expression was activated at the transcription level by free fatty acids (palmitate) in hepatocytes. CCL11 knockdown attenuated whereas CCL11 treatment directly promoted production of pro-inflammatory/pro-lipogenic mediators in hepatocytes. Compared with wild-type littermates, CCL11 knockout mice displayed an ameliorated phenotype of NAFLD when fed a high-fat high-carbohydrate diet as evidenced by decelerated body weight gain, improved insulin sensitivity, dampened lipid accumulation, reduced immune cell infiltration, and weakened liver fibrosis. RNA-seq revealed that interferon regulatory factor 1 as a mediator of CCL11 induced changes in hepatocytes. Importantly, CCL11 neutralisation or antagonism mitigated NAFLD pathogenesis in mice. Finally, a positive correlation between CCL11 expression and NAFLD parameters was identified in human patients. Conclusions: Our data suggest that CCL11 is a novel regulator of NAFLD and can be effectively targeted for NAFLD intervention. Impact and implications: Non-alcoholic fatty liver disease (NAFLD) precedes cirrhosis and hepatocellular carcinoma. In this paper we describe the regulatory role of CCL11, a C-C motif ligand chemokine, in NAFLD pathogenesis. Our data provide novel insights and translational potential for NAFLD intervention.

AutoFibroNet: A deep learning and multi-photon microscopy-derived automated network for liver fibrosis quantification in MAFLD.

BACKGROUND: Liver fibrosis is the strongest histological risk factor for liver-related complications and mortality in metabolic dysfunction-associated fatty liver disease (MAFLD). Second harmonic generation/two-photon excitation fluorescence (SHG/TPEF) is a powerful tool for label-free two-dimensional and three-dimensional tissue visualisation that shows promise in liver fibrosis assessment. AIM: To investigate combining multi-photon microscopy (MPM) and deep learning techniques to develop and validate a new automated quantitative histological classification tool, named AutoFibroNet (Automated Liver Fibrosis Grading Network), for accurately staging liver fibrosis in MAFLD. METHODS: AutoFibroNet was developed in a training cohort that consisted of 203 Chinese adults with biopsy-confirmed MAFLD. Three deep learning models (VGG16, ResNet34, and MobileNet V3) were used to train pre-processed images and test data sets. Multi-layer perceptrons were used to fuse data (deep learning features, clinical features, and manual features) to build a joint model. This model was then validated in two further independent cohorts. RESULTS: AutoFibroNet showed good discrimination in the training set. For F0, F1, F2 and F3-4 fibrosis stages, the area under the receiver operating characteristic curves (AUROC) of AutoFibroNet were 1.00, 0.99, 0.98 and 0.98. The AUROCs of F0, F1, F2 and F3-4 fibrosis stages for AutoFibroNet in the two validation cohorts were 0.99, 0.83, 0.80 and 0.90 and 1.00, 0.83, 0.80 and 0.94, respectively, showing a good discriminatory ability in different cohorts. CONCLUSION: AutoFibroNet is an automated quantitative tool that accurately identifies histological stages of liver fibrosis in Chinese individuals with MAFLD.

Ubiquitin specific peptidase 47 contributes to liver regeneration.

AIMS: Hepatocytes resume proliferation following liver injuries to compensate for the loss of liver mass. Robust liver regeneration is an intrinsic and pivotal process that facilitates restoration of liver anatomy and function. In the present study we investigated the role of ubiquitin-specific peptidase 47 (USP47) in liver regeneration. METHODS AND MATERIALS: Proliferation of hepatocytes was evaluated by Ki67 staining in vivo and EdU incorporation in vitro. DNA-protein interaction was evaluated by chromatin immunoprecipitation (ChIP). RESULTS: USP47 expression was up-regulated in hepatocytes isolated from mice subjected to partial hepatectomy (PHx) or exposed to HGF treatment. Ingenuity pathway analysis revealed E2F1 as a primary regulator of USP47 transcription. Reporter assay and ChIP assay confirmed that E2F1 directly bound to the USP47 promoter and activated USP47 transcription. Consistently, E2F1 knockdown abrogated USP47 induction by HGF. Compared to the wild type littermates, USP47 knockout mice displayed compromised liver regeneration following PHx. In addition, USP47 inhibition by a small-molecule compound impaired liver regeneration in mice. On the contrary, USP47 over-expression enhanced proliferation of hepatocytes in vitro and promoted liver regeneration in mice. Importantly, a positive correlation between USP47 expression and hepatocyte proliferation was identified in patients with acute liver failure (ALF). SIGNIFICANCE: Our data suggest that USP47, transcriptionally activated by E2F1, plays an essential role in liver regeneration.

TRIB1 regulates liver regeneration by antagonizing the NRF2-mediated antioxidant response.

Robust regenerative response post liver injuries facilitates the architectural and functional recovery of the liver. Intrahepatic redox homeostasis plays a key role in liver regeneration. In the present study, we investigated the contributory role of Tribbles homolog 1 (Trib1), a pseudokinase, in liver regeneration and the underlying mechanism. We report that Trib1 expression was transiently down-regulated in animal and cell models of liver regeneration. Further analysis revealed that hepatocyte growth factor (HGF) repressed Trib1 transcription by evicting liver X receptor (LXRα) from the Trib1 promoter. Knockdown of Trib1 enhanced whereas over-expression of Trib1 suppressed liver regeneration after partial hepatectomy in mice. Of interest, regulation of liver regenerative response by Trib1 coincided with alterations of intracellular ROS levels, GSH levels, and antioxidant genes. Transcriptional assays suggested that Trib1 influenced cellular redox status by attenuating nuclear factor erythroid 2-related factor 2 (Nrf2) activity. Mechanistically, Trib1 interacted with the C-terminus of Nrf2 thus masking a potential nuclear localization signal (NLS) and blocking nuclear accumulation of Nrf2. Finally, correlation between Trib1 expression, Nrf2 nuclear localization, and cell proliferation was identified in liver specimens taken from patients with acute liver failure. In conclusion, our data unveil a novel pathway that depicts Trib1 as a critical link between intracellular redox homeostasis and cell proliferation in liver regeneration.

Zinc finger transcription factor Egf1 promotes non-alcoholic fatty liver disease.

Background & Aims: Non-alcoholic fatty liver disease (NAFLD) contributes to the global epidemic of metabolic syndrome and is considered a prelude to end-stage liver diseases such as cirrhosis and hepatocellular carcinoma. During NAFLD pathogenesis, hepatic parenchymal cells (hepatocytes) undergo both morphological and functional changes owing to a rewired transcriptome. The underlying mechanism is not entirely clear. In the present study, we investigated the involvement of early growth response 1 (Egr1) in NAFLD. Methods: Quantitative PCR, Western blotting, and histochemical staining were used to assess gene expression levels. Chromatin immunoprecipitation was used to evaluate protein binding to DNA. NAFLD was evaluated in leptin receptor-deficient (db/db) mice. Results: We report here that Egr1 was upregulated by pro-NAFLD stimuli in vitro and in vivo. Further analysis revealed that serum response factor (SRF) was recruited to the Egr1 promoter and mediated Egr1 transactivation. Importantly, Egr1 depletion markedly mitigated NAFLD in db/db mice. RNA sequencing revealed that Egr1 knockdown in hepatocytes, on the one hand, boosted fatty acid oxidation (FAO) and, on the other hand, suppressed the synthesis of chemoattractants. Mechanistically, Egr1 interacted with peroxisome proliferator-activated receptor α (PPARα) to repress PPARα-dependent transcription of FAO genes by recruiting its co-repressor NGFI-A binding protein 1 (Nab1), which potentially led to promoter deacetylation of FAO genes. Conclusions: Our data identify Egr1 as a novel modulator of NAFLD and a potential target for NAFLD intervention. Impact and Implications: Non-alcoholic fatty liver disease (NAFLD) precedes cirrhosis and hepatocellular carcinoma. In this paper, we describe a novel mechanism whereby early growth response 1 (Egr1), a transcription factor, contributes to NAFLD pathogenesis by regulating fatty acid oxidation. Our data provide novel insights and translational potential for NAFLD intervention.

Association of Diabetes Mellitus with All-Cause and Cause-Specific Mortality among Patients with Metabolic-Dysfunction-Associated Fatty Liver Disease: A Longitudinal Cohort Study.

BACKGROUND: Diabetes mellitus (DM) is a comorbidity commonly presenting with metabolic-dysfunction-associated fatty liver disease (MAFLD); however, few tests for interaction have been reported. Our target was to evaluate the prognostic implications of DM in patients with different forms of MAFLD. METHODS: Using data from the Third National Health and Nutrition Examination Survey (NHANES III) in the United States, we screened 14,797 participants aged 20-74 who received ultrasound examinations from 1988-1994. Among them, 4599 patients met the diagnosis of MAFLD, and we defined mortality as the outcome event. Survival analysis of competitive risk events was performed using Cox regression and sub-distributed risk ratio (SHR). RESULTS: During 21.1 years of follow-up, cardiovascular diseases seemed to be the most common cause of death among MAFLD patients. Of them, DM was present in 25.48% and was independently associated with increased risk of all-cause mortality (HRs: 1.427, 95% CIs: 1.256-1.621, p < 0.001) and cause-specific mortality (cardiovascular-related mortality (HRs: 1.458, 95% CIs: 1.117-1.902, p = 0.005), non-cardiovascular-related mortality (HRs: 1.423, 95% CIs: 1.229-1.647, p < 0.001), and non-cancer-related mortality (HRs: 1.584, 95% CIs: 1.368-1.835, p < 0.001), respectively). Surprisingly, this association was more significant for young patients (p-value for interaction <0.001). Moreover, DM had a greater risk of all-cause and cause-specific mortality among overweight and obese MAFLD patients (p-value for interaction <0.001). CONCLUSIONS: DM increased the risk of all-cause and cause-specific mortality (cardiovascular-related, non-cardiovascular-related, and non-cancer-related) in MAFLD patients, especially in younger patients with excess obesity.

Molecular genetic characteristics of thymic epithelial tumors with distinct histological subtypes.

BACKGROUND: Due to the low incidence and histological heterogeneity, the molecular features and underlying carcinogenic mechanisms of thymic epithelial tumors (TETs) are yet to be fully elucidated, especially for different subtypes of TETs. METHODS: Tumor tissue samples of 43 TETs with distinct histological subtypes were collected. We analyzed the molecular characteristics in different subtypes based on whole exome sequencing data. RESULTS: The mutational profiles of the different subtypes of TETs varied. Compared with thymomas, thymic carcinomas (TCs) had a higher mutation frequency of MYO16 (33% vs. 3%, p = 0.024) and a lower frequency of ZNF729 mutations (0% vs. 35%, p = 0.044). No significant difference was observed in the median tumor mutation burden across different subtypes. The value of copy number variation burden, weighted genome instability index, and the number of amplified segments were all higher in TCs than thymomas, and they also tended to be higher in B3 thymoma than in non-B3 thymomas, while they had no significant differences between B3 thymoma and TCs. Clustering analyses revealed that Wnt, MAPK, Hedgehog, AMPK, and cell junction assembly signaling pathways were exclusively enriched in non-B3 thymomas, lysine degradation pathway in B3 thymoma, and extracellular matrix-receptor (ECM-receptor) interaction, positive regulation of cell cycle process, and activation of innate immune response pathways in TCs. CONCLUSIONS: This study revealed distinct molecular landscapes of different subtypes of TETs, suggesting diverse pathogenesis of non-B3 thymomas, B3 thymomas, and TCs. Our findings warrant further validation in future large-scale studies and may provide a theoretical basis for potential personalized therapeutic strategies.

Targeting WDxR motif reprograms immune microenvironment and inhibits hepatocellular carcinoma progression.

The WD-repeat (WDR) family affects carcinogenesis, but its role in the immune microenvironment is poorly characterized. Although functional loss or gain of WDR6 does not markedly change in vitro proliferative and invasive capacity of HCC cells, its deficiency in hepa1-6 cells drastically inhibits the growth and lung metastasis of orthotopically implanted tumors in immune-competent C57BL/6J mice. Mechanistically, WDR6 targets tumor suppressor UVRAG to the CUL4A-DDB1-ROC1 E3 ubiquitin ligase complex through a unique WDxR motif and promotes its degradation. This upregulates chromatin accessibility at the TNFα locus by blocking autophagic degradation of p65, elevates intratumoral myeloid-derived suppressor cell (MDSC) number, and reduces CD8+ T cell infiltration, thereby promoting HCC progression. These immunosuppressive effects are reversed by TNFα blockade. TNFα recruits NF-κB to activate the transcription of WDR6, establishing a WDR6-TNFα loop. Clinically, the WDR6/UVRAG/NF-κB pathway is hyperactivated in HCC, predicting a poor prognosis. Importantly, a WDxR-like peptide disrupts the WDR6/UVRAG complex and enhances the efficiency of anti-PD-L1 against HCC with WDR6 dysregulation.

Targetable Brg1-CXCL14 axis contributes to alcoholic liver injury by driving neutrophil trafficking.

Alcoholic liver disease (ALD) accounts for a large fraction of patients with cirrhosis and hepatocellular carcinoma. In the present study we investigated the involvement of Brahma-related gene 1 (Brg1) in ALD pathogenesis and implication in ALD intervention. We report that Brg1 expression was elevated in mouse models of ALD, in hepatocyte exposed to alcohol, and in human ALD specimens. Manipulation of Brg1 expression in hepatocytes influenced the development of ALD in mice. Flow cytometry showed that Brg1 deficiency specifically attenuated hepatic infiltration of Ly6G+ neutrophils in the ALD mice. RNA-seq identified C-X-C motif chemokine ligand 14 (CXCL14) as a potential target for Brg1. CXCL14 knockdown alleviated whereas CXCL14 over-expression enhanced ALD pathogenesis in mice. Importantly, pharmaceutical inhibition of Brg1 with a small-molecule compound PFI-3 or administration of an antagonist to the CXCL14 receptor ameliorated ALD pathogenesis in mice. Finally, a positive correlation between Brg1 expression, CXCL14 expression, and neutrophil infiltration was detected in ALD patients. In conclusion, our data provide proof-of-concept for targeting the Brg1-CXCL14 axis in ALD intervention.

MKL1 fuels ROS-induced proliferation of vascular smooth muscle cells by modulating FOXM1 transcription.

Reactive oxygen species (ROS) promotes vascular injury and neointima formation in part by stimulating proliferation of vascular smooth muscle cells (VSMC). The underlying transcriptional mechanism, however, is not completely understood. Here we report that VSMC-specific deletion of MKL1 in mice suppressed neointima formation in a classic model of vascular injury. Likewise, pharmaceutical inhibition of MKL1 activity by CCG-1423 similarly mollified neointima formation in mice. Over-expression of a constitutively active MKL1 in vascular smooth muscle cells enhanced proliferation in a ROS-dependent manner. On the contrary, MKL1 depletion or inhibition attenuated VSMC proliferation. PCR array based screening identified forkhead box protein M1 (FOXM1) as a direct target for MKL1. MKL1 interacted with E2F1 to activate FOXM1 expression. Concordantly, FOXM1 depletion ameliorated MKL1-dependent VSMC proliferation. Of interest, ROS-induced MKL1 phosphorylation through MK2 was essential for its interaction with E2F1 and consequently FOXM1 trans-activation. Importantly, a positive correlation between FOXM1 expression and VSMC proliferation was identified in arterial specimens from patients with restenosis. Taken together, our data suggest that a redox-sensitive phosphorylation-switch of MKL1 activates FOXM1 transcription and mediates ROS fueled vascular smooth muscle proliferation. Targeting the MK-2/MKL1/FOXM1 axis may be considered as a reasonable approach for treatment of restenosis.

Regulatory role and translational potential of CCL11 in liver fibrosis.

BACKGROUND AND AIMS: Myofibroblasts are considered the major effector cell type of liver fibrosis and primarily derived from hepatic stellate cells (HSCs). In the present study, we investigated the contribution of C-C motif chemokine (CCL11) to HSC-myofibroblast trans -differentiation and its implication in liver fibrosis. APPROACH AND RESULTS: We report that CCL11 levels were elevated in HSCs, but not in hepatocytes or Kupffer cells, isolated from mice with liver fibrosis compared with the control mice. CCL11 levels were also up-regulated by 2 pro-fibrogenic growth factors TGF-ß and platelet derived growth factor in cultured HSCs. Mechanistically, zinc finger factor 281 bound to the CCL11 promoter and mediated CCL11 trans -activation in HSCs. Depletion of CCL11 attenuated whereas treatment with recombinant CCL11 promoted HSC activation. Further, global CCL11 deletion ( CCL11-/- ) or HSC/myofibroblast-specific CCL11 knockdown mitigated fibrogenesis in mice. RNA-sequencing revealed that CCL11 might regulate HSC activation by stimulating the transcription of Jagged 1. Reconstitution of Jagged 1 restored the fibrogenic response in CCL11-/- mice. Finally, several targeting strategies that aimed at blockading CCL11 signaling, either by administration of an antagonist to its receptor C-C motif chemokine receptor 3 or neutralizing antibodies against CCL11/C-C motif chemokine receptor 3, ameliorated liver fibrosis in mice. CONCLUSIONS: Our data unveil a previously unrecognized role for CCL11 in liver fibrosis and provide proof-of-concept evidence that targeting CCL11 can be considered as an effective therapeutic approach.