Immunosuppression induces regression of fibrosis in primary biliary cholangitis with moderate-to-severe interface hepatitis.

BACKGROUND: In patients with primary biliary cholangitis (PBC) treated with ursodeoxycholic acid (UDCA), the presence of moderate-to-severe interface hepatitis is associated with a higher risk of liver transplantation and death. This highlights the need for novel treatment approaches. In this study, we aimed to investigate whether combination therapy of UDCA and immunosuppressant (IS) was more effective than UDCA monotherapy. METHODS: We conducted a multicenter study involving PBC patients with moderate-to-severe interface hepatitis who underwent paired liver biopsies. Firstly, we compared the efficacy of the combination therapy with UDCA monotherapy on improving biochemistry, histology, survival rates, and prognosis. Subsequently we investigated the predictors of a beneficial response. RESULTS: This retrospective cohort study with prospectively collected data was conducted in China from January 2009 to April 2023. Of the 198 enrolled patients, 32 underwent UDCA monotherapy, while 166 received combination therapy, consisting of UDCA combined with prednisolone, prednisolone plus mycophenolate mofetil (MMF), or prednisolone plus azathioprine (AZA). The monotherapy group was treated for a median duration of 37.6 months (IQR 27.5-58.1), and the combination therapy group had a median treatment duration of 39.3 months (IQR 34.5-48.8). The combination therapy showed a significantly greater efficacy in reducing fibrosis compared to UDCA monotherapy, with an 8.3-fold increase in the regression rate (from 6.3% to 52.4%, P < 0.001). Other parameters, including biochemistry, survival rates, and prognosis, supported its effectiveness. Baseline IgG >1.3 × ULN and ALP <2.4 × ULN were identified as predictors of regression following the combination therapy. A predictive score named FRS, combining these variables, accurately identified individuals achieving fibrosis regression with a cut-off point of ≥ -0.163. The predictive value was validated internally and externally. CONCLUSION: Combination therapy with IS improves outcomes in PBC patients with moderate-to-severe interface hepatitis compared to UDCA monotherapy. Baseline IgG and ALP are the most significant predictors of fibrosis regression. The new predictive score, FRS, incorporating baseline IgG and ALP, can effectively identify individuals who would benefit from the combination therapy.

Expression and function of myelin expression factor 2 in hepatocellular carcinoma.

INTRODUCTION: Hepatocellular carcinoma (HCC) is one of the most common malignant tumours in the world and has a high mortality rate. However, the pathogenesis of HCC remains unclear. This study aimed to investigate the potential biomarkers of HCC. METHODS: ONCOMINE, HCCDB and THE HUMAN PROTEIN ATLAS were used to identify myelin expression factor 2 (MYEF2) as a potential biomarker for HCC. The Cancer Genome Atlas database was used to further validate and analyse the value of MYEF2. Kaplan-Meier Plotter was used for the prognostic analysis. The COX regression model and Kaplan-Meier method were used to investigate the clinical value of MYEF2 in the prognosis of HCC by reviewing the survival status of patients. Fluorescent quantitative polymerase chain reaction (qPCR) and immunohistochemistry were used to detect the expressions of the MYEF2 mRNA and protein in HCC tissues and cell lines. qPCR and Western blotting were used to validate the efficiency of MYEF2 knockout and overexpression in HCC cells. The invasion and migration abilities regulated by MYEF2 were detected by performing transwell and wound healing assays. RESULTS: MYEF2 is significantly upregulated in HCC and is mainly located in the nucleus of HCC cells. MYEF2 expression is significantly associated with the tumour stage, histological grade and TNM stage. High MYEF2 expression is an independent prognostic factor for patients with HCC. Functionally, elevated MYEF2 facilitated cell migration and invasion in vitro. In contrast, decreased MYEF2 inhibited cell migration and invasion. CONCLUSIONS: MYEF2 may be a novel biomarker with potential diagnosis and prognosis values and as a potential therapeutic target for HCC.

Inhibition of Phosphoinositide 3-Kinase Gamma Protects Endothelial Cells via the Akt Signaling Pathway in Sepsis-Induced Acute Kidney Injury.

INTRODUCTION: Sepsis is a primary cause of death in critically ill patients and is characterized by multiple organ dysfunction, including sepsis-induced acute kidney injury (AKI), which contributes to high mortality in sepsis. However, its pathophysiological mechanisms remain unclear. The kidney has one of the richest and most diversified endothelial cell populations in the body. This study was designed to investigate the effects of endothelial dysfunction in sepsis-induced AKI and explore possible intervention measures to offer new insight into the pathogenesis and treatment of sepsis-induced AKI. METHODS: The circulating levels of endothelial adhesion molecules were detected in patients with sepsis and healthy controls to observe the role of endothelial damage in sepsis and sepsis-induced AKI. A murine sepsis model induced by cecal ligation and perforation was pretreated with a phosphoinositide 3-kinase gamma (PI3Kγ) inhibitor (CZC24832), and survival, kidney damage, and renal endothelial injury were assessed by pathological examination, immunohistochemistry, quantitative polymerase chain reaction, and Western blotting. Lipopolysaccharides and CZC24832 were administered to human umbilical vein endothelial cells in vitro, and endothelial cell function and the expression of adhesion molecules were evaluated. RESULTS: Endothelial damage was more serious in sepsis-induced AKI than that in non-AKI, and the inhibition of PI3Kγ alleviates renal endothelial injury in a murine sepsis model, protecting endothelial cell function and repairing endothelial cell injury through the Akt signaling pathway. CONCLUSIONS: In this study, endothelial cell dysfunction plays an important role in sepsis-induced AKI, and the inhibition of PI3Kγ alleviates endothelial cell injury in sepsis-induced AKI through the PI3Kγ/Akt pathway, providing novel targets for treating sepsis and related kidney injury.

Hsa_circ_0013290 Acts as Cancer-Promoting Gene in Hepatocellular Carcinoma.

BACKGROUND: As a new class of non-coding RNAs, circRNAs have been recently reported to be involved in the tumorigenesis and progression of human cancers. In the current study, we attempted to explore the potential function of a novel circRNA (hsa_circ_0013290) in hepatocellular carcinoma (HCC). METHODS: Relative hsa_circ_0013290 expression was analyzed by quantitative reverse transcription-polymerase chain reaction (qRT-PCR). The subcellular location of hsa_circ_0013290 was performed by RNA subcellular isolation and fluorescence in situ hybridization (FISH) assays. The effect of hsa_circ_0013290 on proliferation was detected by Cell Counting Kit-8 (CCK-8) assays. The effect of hsa_circ_0013290 on cell cycle distribution and apoptosis was detected by flow cytometry. The invasion and migration abilities of hsa_circ_0013290 were detected by transwell assays. RESULTS: Hsa_circ_0013290 is significantly upregulated in HCC cell lines and mainly located in cytoplasm of HCC cells. Hsa_circ_0013290 overexpression promotes cell invasion and migration and inhibits cell apoptosis. In contrast, hsa_circ_0013290 knockdown impedes cell invasion and migration and accelerates cell apoptosis. However, hsa_circ_0013290 did not affect cell proliferation. CONCLUSIONS: Hsa_circ_0013290 is overexpressed in HCC cell lines and is mainly located in the cytoplasm of HCC cells. Hsa_circ_0013290 promotes cell invasion and migration, and inhibits cell apoptosis.

Transmembrane protein 106C promotes the development of hepatocellular carcinoma.

Several protein-coding genes have been identified to play essential roles in cancer biology, and they are dysregulated in many tumors. Transmembrane protein 106C (TMEM106C) is differentially expressed in several human and porcine diseases; however, the expression and biological functions of TMEM106C in hepatocellular carcinoma (HCC) are not clear. In our study, we obtained paired tissue samples from patients undergoing resection for HCC and public databases, which were analyzed for TMEM106C expression using quantitative real-time polymerase chain reaction (qRT-PCR). We further conducted in vitro and in vivo experiments in HCC cell lines and nude mice, respectively, in which TMEM106C was overexpressed or knocked down. Cell-Counting Kit-8 and colony formation experiments were used to determine the influence of TMEM106C on cell proliferation, flow cytometric assays were used to detect the influence on cell cycle distribution and apoptosis, and transwell assays were used for detecting changes in cell migration and invasion. TMEM106C levels were significantly elevated in HCC tissues and cell lines from public databases and our collected specimens from patients. Moreover, higher TMEM106C expression levels predicted a poor prognosis in HCC patients in survival analysis. Overexpression of TMEM106C in HCC cells accelerated cell growth, migration, and invasion, but it inhibited cell apoptosis by targeting forkhead box O-1 (FOXO1) and FOXO3. Conversely, TMEM106C knockdown impeded cell proliferation and metastasis, whereas it enhanced the rate of apoptosis. More important, knockdown of the expression of TMEM106C in HCC cells inhibited the growth of xenograft tumors in vivo. Collectively, these results suggest that TMEM106C acts as an oncogene and can serve as a potential therapeutic target for HCC in the future.

RANK/RANKL Acts as a Protective Factor by Targeting Cholangiocytes in Primary Biliary Cholangitis.

BACKGROUND: Primary biliary cholangitis (PBC) is an autoimmune liver disease characterized by the highly selective autoimmune injury of small intrahepatic bile ducts. Studies reported that the cholangiocytes from PBC patients expressed significantly higher levels of both receptor activator of nuclear factor-kappa B (RANK) and its ligand RANKL. However, the accurate role of RANK/RANKL axis in PBC remains unclear. METHODS: Forty patients with PBC were enrolled according to the inclusion criteria. The biochemical parameters (alkaline phosphatase, ALP; gamma-glutamyltransferase, GGT; alanine aminotransferase, ALT; aspartate transaminase, AST; total bilirubin, TB) were collected at baseline and followed-up after 6 months of treatment with ursodeoxycholic acid (UDCA, 15 mg/kg d). Stages of PBC were diagnosed based on liver biopsy histopathology according to Nakanuma's criteria. RANK expression in hepatic tissues was detected by immunohistochemistry. The cellular immunofluorescence method was used to locate the distribution of RANK in the human intrahepatic biliary epithelial cells (HIBECs) cultured in vitro. HIBECs were treated with RANKL at a concentration of 100 ng/ml or transfected with RANK-overexpressing lentivirus (LV-RANK). CCK-8 assay and cell cycle assay were used to detect the cell proliferation. Real-time PCR was used to detect the expression of IL-6, E-cadherin, VCAM, ICAM-1, TNF-α, and CD80. RESULTS: RANK expression in liver biopsies from early PBC patients (stage I + stage II) was significantly lower than that from advanced PBC patients (stage III + stage IV) (1.7 ± 0.63 vs. 2.3 ± 0.45 scores, P < 0.05). High-RANK patients seemed to have better response to UDCA than low-RANK patients (88.9% vs. 40.9%, P < 0.05). The baseline biochemical parameters between the two groups were comparable. The decline percentages of ALP and GGT after UDCA treatment were more obvious in high-RANK patients than those in low-RANK patients (53.90% ± 9.82% vs. 23.93% ± 6.24%, P < 0.05; 74.11% ± 7.18% vs. 48.00% ± 8.17%, P < 0.05, respectively). HIBECs proliferation was significantly inhibited after treatment of RANKL or transfection with LV-RANK. Increased expression of IL-6 and E-cadherin was observed in HIBECs treated with RANKL or LV-RANK. CONCLUSION: The overall hepatic RANK expression was associated with disease severity and biochemical response in PBC patients. Activation of RANK/RANKL signaling pathway inhibited cholangiocytes proliferation in vitro. Our study suggested that RANK/RANKL pathway might be a potential target of immunotherapy of PBC based on its involvement in the occurrence and development of the disease.

Long Non-Coding RNA (lncRNA) NEAT1 Aggravates Cerebral Ischemia-Reperfusion Injury by Suppressing the Inhibitory Effect of miR-214 on PTEN.

BACKGROUND Cerebral ischemia-reperfusion injury is a form of serious nervous system injury. Activation of the PI3K/Akt pathway can effectively relieve cerebral ischemia-reperfusion injury. miR-214 can target and inhibit the expression of PTEN, thereby alleviating its inhibitory effect on the PI3K/Akt pathway. Moreover, lncRNA NEAT1 was reported to affect proliferation and metastasis of tumor cells by targeting and suppressing the expression of miR-214. However, whether lncRNA NEAT1 affects the cerebral ischemia-reperfusion-induced damage by regulating the miR-214/PTEN/PI3K/Akt pathway is unclear. MATERIAL AND METHODS The miR-214 agomir and miR-214 antagomir were designed and injected into the encephalocele of MCAO rats. Next, the production of oxidative stress kinase and apoptosis of brain cells were detected using commercial kits. The levels of PTEN, PI3K, Akt, p-Akt, and VEGF in brain tissues were determined. Next, the targeting effect of lncRNA NEAT1 and miR-214 was determined with luciferase reporter assay. RESULTS Overexpression of miR-214 relieved the apoptosis and oxidative stress of brain tissues. Overexpression of miR-214 promoted the expression of PI3K, Akt, p-Akt, and VEGF by inhibiting the production of PTEN. However, overexpression of lncRNA NEAT1 repressed the remission effect of miR-214 on cerebral ischemia-reperfusion-induced damage and inhibited the production of PI3K, Akt, p-Akt, and VEGF by rescuing the levels of PTEN. CONCLUSIONS lncRNA NEAT1 aggravates cerebral ischemia-reperfusion injury by abolishing the activation effect of miR-214 on the PI3K/Akt pathway.

Nucleolar spindle-associated protein 1 promotes tumorigenesis and predicts poor prognosis in human esophageal squamous cell carcinoma.

The microtubule binding protein, nucleolar spindle-associated protein 1 (NUSAP1), has a crucial function in mitosis and its expression is closely associated with carcinogenesis. Herein, we aimed to determine the function of NUSAP1 in the development of human esophageal squamous cell carcinoma (ESCC), and the association of NUSAP1 expression with ESCC. Immunohistochemical staining of ESCC tissue sections indicated that NUSAP1 was expressed to a higher degree in tumor tissues than in adjacent nontumor tissues. NUSAP1 levels were relevant closely to histological differentiation (P = 0.049). Overall survival was longer in patients with lower NUSAP1 levels ( P < 0.001). NUSAP1 expression ( P = 0.002), histological differentiation ( P < 0.001), tumor depth ( P = 0.045), lymph node metastases ( P < 0.001), and tumor-node-metastasis staging ( P = 0.008) were greatly associated with overall survival using univariate analysis. Multivariate analysis suggested that histological differentiation ( P = 0.014) and NUSAP1 expression ( P = 0.026) could be independent prognostic markers for ESCC. Additionally, the biological behavior of ESCC cells was investigated in vitro and in vivo. Suppression of NUSAP1 inhibited cellular proliferation and invasion, and induced cell cycle arrest and apoptosis in vitro. More importantly, knockdown of NUSAP1 led to inhibition of tumor formation in nude mice. These findings indicated that NUSAP1 is a potential prognostic biomarker in ESCC, and is an ESCC oncogene. Thus, NUSAP1 could represent a therapeutic target for ESCC.

Correction to: Circular RNA YAP1 inhibits the proliferation and invasion of gastric cancer cells by regulating the miR-367-5p/p27 Kip1 axis.

After the publication of this work [1], a spelling error was found: the ID of the circRNA, termed circYAP1, in the original publication was misspelled as "has_circ_0002320".

A functional characteristic of cysteine-rich protein 61: Modulation of myeloid-derived suppressor cells in liver inflammation.

There is increasing awareness of the immunologic roles of liver mononuclear populations, including myeloid-derived suppressor cells (MDSCs). We took advantage of a large well-defined cohort of 148 patients with liver inflammation and 45 healthy controls to focus on the qualitative and quantitative characteristics of MDSCs. We investigated the frequency, phenotype, and functional capacities of MDSCs by using peripheral blood MDSCs in a cohort of 55 patients with primary biliary cholangitis (PBC), 40 with autoimmune hepatitis, 39 with chronic hepatitis B, 14 with nonalcoholic fatty liver disease, and 45 healthy controls. This was followed by a liver-targeted determination in 27 patients with PBC, 27 with autoimmune hepatitis, 20 with chronic hepatitis B, 14 with nonalcoholic fatty liver disease, and 6 controls. We then focused on mechanisms of this expansion with PBC as an example, using both ursodeoxycholic acid-naive and treated patients. HLA-DR-/low CD33+ CD11b+ CD14+ CD15- monocytic MDSCs were elevated in diseases characterized by liver inflammation compared to healthy controls. Using PBC as a focus, there was a significant correlation between levels of circulating MDSCs and disease-related biochemical markers (alkaline phosphatase, total bilirubin). We found higher amounts of MDSCs in patients with PBC who were responsive to ursodeoxycholic acid. MDSCs from PBC were found to manifest a potent immunosuppressive function. There was a significant correlation in the accumulation of hepatic MDSCs in the inflamed lesions of PBC with histologic changes, such as fibrosis. We also found that cysteine-rich protein 61 (CCN1), a highly expressed protein in impaired cholangiocytes and hepatocytes, contributes to MDSC expansion and MDSC inducible nitric oxide synthase-associated immune suppression. CONCLUSION: CCN1 modulates expansion and a suppressive function of MDSCs. Our data highlight the potential functions of CCN1 on MDSCs and suggest therapeutic implications in inflammatory liver diseases. (Hepatology HEPATOLOGY 2018;67:232-246).

Circular RNA YAP1 inhibits the proliferation and invasion of gastric cancer cells by regulating the miR-367-5p/p27 Kip1 axis.

BACKGROUND: Circular RNAs (circRNAs) are a new type of non-coding RNAs and their functions in gastric cancer (GC) remain unclear. Recent studies have revealed that circRNAs play an important role in cancer development and certain types of pathological responses, acting as microRNA (miRNA) sponges to regulate gene expression. METHODS: CircNet was used to screen potential circRNAs and validated circYAP1 expression levels in 17 GC tissues by quantitative real-time PCR (qRT-PCR) and another 80 paired GC tissues by FISH. CircYAP1 overexpression and knockdown experiments were conducted to assess the effects of circYAP1 in vitro and in vivo, and its molecular mechanism was demonstrated by RNA in vivo precipitation assays, western blotting, luciferase assay and rescue experiments. RESULTS: CircYAP1 expression level was significantly lower in GC tissues than the adjacent normal tissues, and GC patients with circYAP1 low expression had shorter survival times as compared with those with circYAP1 high expression. Functionally, circYAP1 overexpression inhibited cell growth and invasion in vitro and in vivo, but its knockdown reversed these effects. Further analysis showed that circYAP1 sponged miR-367-5p to inhibit p27 Kip1 expression and GC progression. CONCLUSION: Our findings demonstrate that circYAP1 functions as a tumor suppressor in GC cells by targeting the miR-367-5p/p27 Kip1 axis and may provide a prognostic indicator of survival in GC patients.

The immunobiology of mucosal-associated invariant T cell (MAIT) function in primary biliary cholangitis: Regulation by cholic acid-induced Interleukin-7.

Mucosal-associated invariant T (MAIT) cells are novel innate-like T cells constituting a significant proportion of circulating and hepatic T cells. Herein, we extensively examine the phenotypical and functional alterations of MAIT cells and their regulation in a cohort of 56 patients with Primary Biliary Cholangitis (PBC) and 53 healthy controls (HC). Additionally alterations of MAIT cells were assessed before and after UDCA treatment. Finally the localization of MAIT cell in liver was examined using specific tetramer staining and the underlying mechanisms of these alterations in PBC were explored. Our data demonstrated that the frequency and number of circulating MAIT cells were decreased, whereas hepatic MAIT cells were increased in PBC compared to HC. Moreover, circulating MAIT cells were more activated in PBC than HC, reflected by elevated expression levels of granzyme B. Six months of UDCA treatment significantly attenuated the circulating MAIT cells differences in PBC. Of note, the expression levels of IL-7 were significantly increased in both plasma and liver from PBC as compared to HC, which promoted the production of inflammatory cytokines and granzyme B by inducing signal transduction and activation of transcription 5 (STAT5) phosphorylation in MAIT cells. Finally, cholic acid, one of the major bile acids in liver, upregulated IL-7 expression in hepatocyte cell line L02 by inducing Farnesoid X Receptor (FXR) binding to the IL-7 promoter. Hence MAIT cells are activated and enriched in the liver of PBC. Cholic acid-induced IL-7 production in hepatocytes plays a critical role in regulating MAIT cell function, highlighting that hepatocytes may bridge cholangiocyte injury and innate immunity through a bile acid signaling pathway.

Hypoxia-inducible factor-2α promotes hepatocyte apoptosis during cholestasis.

AIM: Hypoxia-inducible factor-2α (HIF-2α) has been reported to play an important role in a host of pathophysiological processes, including cellular survival. This study explores the role of HIF-2α in cholestasis-mediated hepatocyte apoptosis. METHODS: Hypoxia-inducible factor-2α expression was measured by immunohistochemistry and confocal microscopy. Hepatic apoptosis was detected by terminal deoxynucleotidyl transferase-mediated dUTP-digoxigenin nick-end labeling. The cholestatic mouse model was treated with bile duct ligation. The c-myc, p53, and Bax protein levels were measured with Western blot analysis. RESULTS: In pediatric and murine cholestatic liver tissues, HIF-2α protein was widely expressed in the nucleus of parenchymal cells as well as in stromal cells. Hepatocyte HIF-2α expression was significantly elevated at the early stage of pediatric cholestasis and decreased at the late stage. In both in vivo and in vitro murine studies, HIF-2α deletion could alleviate cholestasis-mediated hepatocyte apoptosis and regulate the expression of c-myc, p53, and Bax proteins. CONCLUSION: These findings implied the contribution of HIF-2α to cholestasis-mediated hepatocyte apoptosis.

Association of chronic hepatitis B virus infection with preterm birth: our experience and meta-analysis.

OBJECTIVES: To assess the association of chronic hepatitis B virus (HBV) infection with preterm birth (PTB). METHODS: A cohort of 20,498 pregnant women (497 HBV carriers with 20,001 non-HBV controls) with normal alanine aminotransferase (ALT) levels was selected from the Obstetrics & Gynecology Hospital of Nantong University. The clinical parameters and PTB incidence were compared between HBV carriers and non-HBV subjects. For the meta-analysis, we searched the PubMed, Ovid and Cochrane Library databases for studies comparing PTB incidence between individuals with chronic HBV infection and non-HBV subjects. RESULTS: HBV carriers were slightly older and had slightly higher ALT levels within normal limits. The body mass index, education and history of pregnancy between HBV carrier and non-HBV groups were comparable. PTB incidence was not associated with HBV carrier status [relative risk (RR) 0.98, 95% confidence interval (CI) 0.71-1.37] in our cohort. However, the meta-analysis involving eight published studies and our study revealed a significant association between chronic HBV infection and PTB incidence (pooled RR 1.26, 95% CI 1.19-1.33). CONCLUSION: While maternal HBV carriers did not have a higher incidence of PTB in our cohort, the meta-analysis indicates that individuals with chronic HBV infection appeared to be at risk of PTB as a whole.

Logistic regression model can reduce unnecessary artificial liver support in hepatitis B virus-associated acute-on-chronic liver failure: decision curve analysis.

BACKGROUND: Several models have been proposed to predict the short-term outcome of acute-on-chronic liver failure (ACLF) after treatment. We aimed to determine whether better decisions for artificial liver support system (ALSS) treatment could be made with a model than without, through decision curve analysis (DCA). METHODS: The medical profiles of a cohort of 232 patients with hepatitis B virus (HBV)-associated ACLF were retrospectively analyzed to explore the role of plasma prothrombin activity (PTA), model for end-stage liver disease (MELD) and logistic regression model (LRM) in identifying patients who could benefit from ALSS. The accuracy and reliability of PTA, MELD and LRM were evaluated with previously reported cutoffs. DCA was performed to evaluate the clinical role of these models in predicting the treatment outcome. RESULTS: With the cut-off value of 0.2, LRM had sensitivity of 92.6 %, specificity of 42.3 % and an area under the receiving operating characteristic curve (AUC) of 0.68, which showed superior discrimination over PTA and MELD. DCA revealed that the LRM-guided ALSS treatment was superior over other strategies including "treating all" and MELD-guided therapy, for the midrange threshold probabilities of 16 to 64 %. CONCLUSIONS: The use of LRM-guided ALSS treatment could increase both the accuracy and efficiency of this procedure, allowing the avoidance of unnecessary ALSS.

Treatment of cholestatic fibrosis by altering gene expression of Cthrc1: Implications for autoimmune and non-autoimmune liver disease.

Collagen triple helix repeat containing-1 (Cthrc1) is a documented specific inhibitor of TGF-ß signaling. Based on this observation, we developed the hypothesis that knocking in/knocking out the Cthrc1 gene in murine models of cholestasis would alter the natural history of cholestatic fibrosis. To study this thesis, we studied two murine models of fibrosis, first, common bile duct ligation (CBDL) and second, feeding of 3, 5-diethoxy-carbonyl-1, 4-dihydrocollidine (DDC). In both models, we administered well-defined adenoviral vectors that expressed either Cthrc1 or, alternatively, a short hairpin RNA (shRNA)-targeting Cthrc1 either before or after establishment of fibrosis. Importantly, when Cthrc1 gene expression was enhanced, we noted a significant improvement of hepatic fibrosis, both microscopically and by analysis of fibrotic gene expression. In contrast, when Cthrc1 gene expression was deleted, there was a significant exacerbation of fibrosis. To identify the mechanism of action of these significant effects produced by knocking in/knocking out Cthrc gene expression, we thence studied the interaction of Cthrc1 gene expression using hepatic stellate cells (HSCs) and human LX-2 cells. Importantly, we demonstrate that Cthrc1 is induced by TGF-ß1 via phospho-Smad3 binding to the promoter with subsequent transcription activation. In addition, we demonstrate that Cthrc1 inhibits TGF-ß signaling by accelerating degradation of phospho-Smad3 through a proteosomal pathway. Importantly, the anti-fibrotic effects can be recapitulated with a truncated fragment of Cthrc1. In conclusion, our findings uncover a critical negative feedback regulatory loop in which TGF-ß1 induces Cthrc1, which can attenuate fibrosis by accelerating degradation of phospho-Smad3.

Autoimmune hepatitis: East meets west.

Autoimmune hepatitis (AIH) is an inflammatory liver disease with diverse clinical spectrum, which predominantly affects females. This review provides detailed comparisons of epidemiology, genetic predispositions, clinical features, risk factors of hepatocellular carcinoma, and mortality in AIH patients between eastern and western countries. AIH prevalence and incidence are lower in Asia-Pacific area than in Europe and America. European and American patients seem to have more severe disease, characterized with human leukocyte antigen-DR3 haplotype, younger age, more AIH-induced "cirrhosis" at diagnosis, higher elevated serum immunoglobulin G levels, and positive rate of antisoluble liver antigen/liver pancreatitis. The overall AIH diagnostic accuracy of revised original criteria and simplified scoring system are similar in European/American populations and Asian. Cirrhosis at presentation and non-response to immunosuppressive therapy within 1 year are the most important predictors for poor prognosis of AIH patients.

The critical role of myeloid-derived suppressor cells and FXR activation in immune-mediated liver injury.

The immunobiology of FXR has attracted significant attention in immune regulation and innate immunity. We have studied the mechanism of action of FXR activation on two models of acute hepatitis, inflammation mediated by Con A and α-GalCer and focused on the interactions of FXR activation and expression of PIR-B, both in vivo and in vitro using luciferase reporter and CHIP assays. In addition, based upon our data, we studied the role of FXR activation on the immunobiology of myeloid-derived suppressor cells (MDSCs). Importantly, we report herein that FXR activation reduces the inflammatory insult induced by either α-GalCer or Con A; such treatment expands CD11b(+)Ly6C(+) MDSCs. The protective effect of FXR activation is dependent on expansion of MDSCs, particularly liver CD11b(+)Ly6C(high) cells. Indeed, FXR activation enhances the suppressor function of MDSCs through upregulation of PIR-B by binding the PIR-B promoter. FXR activation drives the accumulation of MDSCs to liver through upregulation of S100A8. FXR activation facilitates homing and function of MDSCs, which function as a critical negative feedback loop in immune-mediated liver injury. The novel mechanisms defined herein emphasize not only the importance of liver lymphoid subpopulations, but also the potential roles of modulating FXR in autoimmune liver disease.

Hsa_circ_0079875 functions as a competitive endogenous RNA to promote hepatocellular carcinoma progression.

Circular RNA (circRNA) can influence the development of hepatocellular carcinoma (HCC) as a competitive endogenous RNA (ceRNA). However, there are still many circRNAs whose functions are unknown. Our research explores the role of a novel circRNA, hsa_circ_0079875, in HCC. The expression of hsa_circ_0079875 in HCC was verified by next-generation sequencing, quantitative reverse transcription-polymerase chain reaction (qRT-PCR), and fluorescence in situ hybridization (FISH). The distribution of hsa_circ_0079875 in HCC cells was investigated by RNA subcellular isolation and FISH assays. The functional effects on HCC proliferation, invasion, migration, cell cycle, and apoptosis were verified by overexpression and knockdown of hsa_circ_0079875. Moreover, xenograft mouse models and immunohistochemistry experiments were used to assess the function of hsa_circ_0079875 in vivo. Hsa_circ_0079875 was up-regulated in HCC tissues and mainly distributed in the cytoplasm. Higher hsa_circ_0079875 leads to larger tumor tissue, more microvascular invasion(MVI) and higher AFP levels, which in turn leads to a poor prognosis. Overexpression of hsa_circ_0079875 can promote the proliferation, migration, and invasion of HCC cells and inhibit apoptosis in vitro and in vivo. Knocking down hsa_circ_0079875 has the opposite effect. Sequencing and biological information predicted the target miRNA and mRNA of hsa_circ_0079875. Further bioinformatics and clinical correlation analysis revealed that hsa_circ_0079875 promote the malignant biological behaviors of HCC through hsa_circ_0079875/miR-519d-59/NRAS ceRNA net. Therefore, hsa_circ_0079875 can be a potential prognostic marker and therapeutic target for HCC.

CCN1 expression in hepatocytes contributes to macrophage infiltration in nonalcoholic fatty liver disease in mice.

Our objective was to investigate the potential roles of CCN1 in the inflammation and macrophage infiltration of nonalcoholic fatty liver disease (NAFLD). The regulation of hepatic CCN1 expression was investigated in vitro with murine primary hepatocytes treated with free fatty acids or lipopolysaccharide (LPS) and in vivo with high-fat (HF) diet-fed mice or ob/ob mice. CCN1 protein and a liver-specific CCN1 expression plasmid were administered to mice fed a normal diet (ND) or HF diet. Myeloid-derived macrophages and RAW264.7 cells were also treated with CCN1 in vitro to determine the chemotactic effects of CCN1 on macrophages. LPS treatment significantly increased hepatic CCN1 expression in HF diet-fed mice and ob/ob mice. LPS and FFAs induced CCN1 expression in primary murine hepatocytes in vitro through the TLR4/MyD88/AP-1 pathway. CCN1 protein and overexpression of CCN1 in the liver induced more severe hepatic inflammation and macrophage infiltrates in HF mice than in ND mice. CCN1 recruited macrophages through activation of the Mek/Erk signaling pathway in myeloid-derived macrophages and RAW264.7 cells in vitro. Endotoxin and FFA-induced CCN1 expression in hepatocytes is involved in the hepatic proinflammatory response and macrophage infiltration in murine NAFLD.