CD44 is a key player in non-alcoholic steatohepatitis.

BACKGROUND & AIMS: Cluster of differentiation (CD)44 regulates adipose tissue inflammation in obesity and hepatic leukocyte recruitment in a lithogenic context. However, its role in hepatic inflammation in a mouse model of steatohepatitis and its relevance in humans have not yet been investigated. We aimed to evaluated the contribution of CD44 to non-alcoholic steatohepatitis (NASH) development and liver injury in mouse models and in patients at various stages of non-alcoholic fatty liver disease (NAFLD) progression. METHODS: The role of CD44 was evaluated in CD44-/- mice and after injections of an αCD44 antibody in wild-type mice challenged with a methionine- and choline-deficient diet (MCDD). In obese patients, hepatic CD44 (n=30 and 5 NASH patients with a second liver biopsy after bariatric surgery) and serum sCD44 (n=64) were evaluated. RESULTS: Liver inflammation (including inflammatory foci number, macrophage and neutrophil infiltration and CCL2/CCR2 levels), liver injury and fibrosis strongly decreased in CD44-/- mice compared to wild-type mice on MCDD. CD44 deficiency enhanced the M2 polarization and strongly decreased the activation of macrophages by lipopolysaccharide (LPS), hepatocyte damage-associated molecular patterns (DAMPs) and saturated fatty acids. Neutralization of CD44 in mice with steatohepatitis strongly decreased the macrophage infiltration and chemokine ligand (CCL)2 expression with a partial correction of liver inflammation and injury. In obese patients, hepatic CD44 was strongly upregulated in NASH patients (p=0.0008) and correlated with NAFLD activity score (NAS) (p=0.001), ballooning (p=0.003), alanine transaminase (p=0.005) and hepatic CCL2 (p<0.001) and macrophage marker CD68 (p<0.001) expression. Correction of NASH was associated with a strong decrease in liver CD44+ cells. Finally, the soluble form of CD44 increased with severe steatosis (p=0.0005) and NASH (p=0.007). CONCLUSION: Human and experimental data suggest that CD44 is a marker and key player of hepatic inflammation and its targeting partially corrects NASH. LAY SUMMARY: Human and experimental data suggest that CD44, a cellular protein mainly expressed in immune cells, is a marker and key player of non-alcoholic steatohepatitis (NASH). Indeed, CD44 enhances the non-alcoholic fatty liver (NAFL) (hepatic steatosis) to NASH progression by regulating hepatic macrophage polarization (pro-inflammatory phenotype) and infiltration (macrophage motility and the MCP1/CCL2/CCR2 system). Targeting CD44 partially corrects NASH, making it a potential therapeutic strategy.

Severe Vitamin D Deficiency Is Not Associated with Liver Damage in Morbidly Obese Patients.

BACKGROUND AND AIMS: A deficiency in vitamin D could be deleterious during chronic liver diseases. However, contradictory data have been published in patients with non-alcoholic fatty liver disease. The aim of the study was to compare the blood level of 25 hydroxy vitamin D (25-OH vitamin D) with the severity of liver lesions, in a large cohort of morbidly obese patients. PATIENTS AND METHOD: Three hundred ninety-eight morbidly obese patients had a liver biopsy. The non-alcoholic steatohepatitis (NASH) Clinical Research Network Scoring System Definition and Scores were used. 25-OH vitamin D was evaluated with a Diasorin®Elisa Kit. Logistic regression analyses were performed to obtain predictive factors of the severity of liver histology. RESULTS: 20.6 % of patients had NASH. The stage of fibrosis was F0 12.9 %, F1 57.36 %, F2 25.32 %, F3 (bridging fibrosis) 3.88 %, and F4 (cirrhosis) 0.52 %. The 25-OH vitamin D level inversely correlated to the NAS (r = 0.12 and p = 0.01) and to steatosis (r = 0.14 and p = 0.007); however, it was not associated with the presence of NASH. The level of vitamin D was significantly lower in patients with significant fibrosis compared to those without (15.9 (11.1-23.5) vs 19.6 (13.7-24.7) ng/ml, p = 0.02). There was an inverse correlation between the severity of fibrosis and the values of 25-OH vitamin D (r = 0.12 and p = 0.01). In a logistic regression analysis, no parameters were independently associated with the severity of fibrosis except the presence of steatohepatitis (1.94 (1.13-3.35) p = 0.017). CONCLUSION: Low levels of 25-OH vitamin D were not independently associated with liver damage in morbidly obese patients with non-alcoholic fatty liver diseases (NAFLD).

Inflammatory hepatocellular adenomas developed in the setting of chronic liver disease and cirrhosis.

Hepatocellular adenoma is considered to occur exclusively in non-fibrotic livers. It is a heterogeneous entity and a molecular classification is now widely accepted. The most frequent hepatocellular adenoma subtype, namely inflammatory adenoma, harbor somatic activating mutations of genes involved in the interleukin-6 pathway that lead to high C-reactive protein and serum amyloid A expression. The aim of our study was to investigate a series of benign hepatocellular neoplasms developed on cirrhotic livers and characterized by an unequivocal histological diagnosis. We performed a clinical, pathological, and molecular study of 10 benign hepatocellular neoplasms developed in three patients with cirrhosis. Markers allowing hepatocellular adenoma classification were assessed by quantitative real-time PCR and immunohistochemistry. Samples were sequenced for CTNNB1, HNF1A, IL6ST, GNAS, STAT3, and TERT (promoter) mutations. A control series of 32 classical macronodules developed in cirrhosis related to various etiologies was screened by immunohistochemistry and gene sequencing. The three patients had cirrhosis related to metabolic syndrome and/or alcohol intake; two had a single tumor, while the third developed more than 30 lesions. Microscopic examination showed well-differentiated neoplasms sharing features with inflammatory adenoma including inflammatory infiltrates, sinusoidal dilatation, and dystrophic vessels. Sequencing revealed classical hotspot somatic mutations (IL6ST, n=8; STAT3, n=1; and GNAS, n=1) known to be responsible for IL-6/JAK/STAT pathway activation. Two classical high-grade macronodules demonstrated high serum amyloid A and/or C-reactive protein expression, without gene mutations. Altogether, our findings support the existence of rare inflammatory adenoma developed in cirrhosis.

Immunoglobulin G4-associated autoimmune hepatitis may be found in Western countries.

BACKGROUND: Immunoglobulin G4-related disease is a multi-systemic autoimmune disease. The sole involvement of the liver has been recently reported in Japanese patients and named "immunoglobulin G4-associated autoimmune hepatitis". AIM: To examine the baseline and the 2-year follow-up characteristics of non-Asian patients with immunoglobulin G4-associated autoimmune hepatitis compared to patients with classical autoimmune hepatitis. METHODS: This was a retrospective study of patients who had undergone liver biopsy between March 2009 and January 2012 before starting any treatment. All patients were treated according to the guidelines. Immunoglobulin G4-associated autoimmune hepatitis was diagnosed according to Umemura's histological definition: at least 10 positive immunoglobulin G4-plasma cells per high power field. RESULTS: Among 28 enrolled patients (males 39%, median age 54 years): 7 had immunoglobulin G4-associated autoimmune hepatitis (25%) and 21 had classical hepatitis; fibrosis and activity stages were F1: 57%, F2: 11%, F3: 11%, F4: 21% and A1: 18%, A2: 39%, A3: 43%. Alanine aminotransferase (ALT) activity and serum immunoglobulin G levels were similar in the two groups at baseline and at 2 years. Complete biochemical response (normal ALT) was similar in immunoglobulin G4-associated autoimmune hepatitis and classical hepatitis (67% vs. 59% at 2 years, p=0.74). CONCLUSION: Immunoglobulin G4-associated autoimmune hepatitis has been observed in Western patients and seems to evolve in a similar manner to classical hepatitis.

Spatio-temporal genetic heterogeneity of CTNNB1 mutations in sporadic desmoid type fibromatosis lesions.

Desmoid type fibromatosis (DT) is a rare lesion of unclear pathogenesis that most often presents a mutation of the (ß-catenin) gene. The natural history and clinical evolution are highly variable between patients and to date there is no consensus on optimal therapy. We report two cases of a patient with multiple DT lesions. Molecular investigations performed in both patients on multiple tumors at different anatomical sites revealed non-identical CTNNB1 mutations. The first patient was a 39-year-old man with a history of recurrent DT. In two of the DT lesions, three different mutations were found in codons 41 and 45, respectively. The lesions showed marked inflammatory features, characterized by IgG4 positive lymphoplasmacytic infiltrates and a foreign body reaction, which increased in intensity over time. The patient was eventually treated with a COX-2 inhibitor and the remaining mass was stabilized. In the two DT lesions of the second patient, CTNNB1 mutations S45P and T41A were found. The presence of different mutations in multiple focally recurrent sporadic DT lesions indicates that they do not have a clonal relationship. Our data suggest that a CTNNB1 mutation is a necessary event probably by providing a selective growth advantage. An IgG4 host antigen response is discussed as a potential predisposing factor for one of the patients.

Prospective randomized comparison of endoscopic submucosal tunnel dissection and conventional submucosal dissection in the resection of superficial esophageal/gastric lesions in a living porcine model.

BACKGROUND AND STUDY AIMS: To assess experimentally endoscopic submucosal tunnel dissection (ESTD) as an alternative technique of endoscopic submucosal resection. PATIENTS AND METHODS: This was a prospective, randomized, comparative experimental animal study carried out over a period of 9 months at the surgical research and teaching center of Aix-Marseille University, France. Virtual esophageal and gastric lesions measuring 3 cm in diameter were resected in pigs weighing 25 to 30 kg. The primary aim was to evaluate ESTD's efficacy compared with endoscopic submucosal dissection (ESD). The secondary aims were to determine complication rates as well as to assess procedure time and procedure speed, histologic quality of the resected specimen, and procedure cost. RESULTS: Eighteen procedures (9 ESD and 9 ESTD) were performed in nine pigs. The technical success rate was 88.9 % for both techniques, with one single failure in each. The en bloc resection rate was 100 % for ESTD and 88.9 % for ESD (one failure). The complication rate (22 %) and median procedure time were similar but dissection speed was quicker with ESTD in the esophagus (P = 0.03). Median procedure cost (728 Euros for ESD and ESTD) did not differ. On histologic examination, the lateral margins were healthy in 100 % of ESTD and in 88.9 % of ESD (P = 0.49). Deep resection margins were of better quality in ESTD (median submucosal thickness: 1307.1 µm vs. 884.7 µm; P = 0.039). CONCLUSIONS: ESTD is feasible and safe but not superior in the treatment of superficial esophageal/gastric lesions in porcine models compared with ESD. Nevertheless it provides a better quality histologic specimen.

Severe Vitamin D Deficiency May be an Additional Cofactor for the Occurrence of Alcoholic Steatohepatitis.

BACKGROUND: Among its pleiotropic effects, vitamin D may protect the liver from fibrosis and/or inflammation. However, the impact of vitamin D on liver pathology in hepatitis C remains unclear, and very few studies including alcoholic patients with liver pathologies have been performed. Here we compared the levels of 25-OH vitamin D in the blood of alcoholic patients with the occurrence of alcoholic steatohepatitis (ASH) or bridging fibrosis. METHODS: One hundred and one alcoholic patients were included. All the patients received a liver biopsy, and the levels of 25-OH vitamin D were evaluated with the Liaison 25-OH vitamin D assay. Logistic regression analyses were performed to obtain predictive factors of liver histology. RESULTS: Among alcoholic patients, 40.6% presented ASH and 39.6% presented bridging fibrosis. A severe deficiency in 25-OH vitamin D (<10 ng/ml) was seen in 60.4% of patients. This deficiency was frequent in patients with ASH (85.4%) and in those with bridging fibrosis (80%) but was independently associated only with ASH (odds ratio = 8.46 [95% confidence interval 2.05 to 34.89], p = 0.003). CONCLUSIONS: In alcoholic patients, a severe deficiency in 25-OH vitamin D was independently associated with the occurrence of ASH.

Primary biliary cirrhosis: proposal for a new simple histological scoring system.

BACKGROUND & AIMS: A simple and reproducible evaluation of non diagnostic histological lesions related to prognosis remains crucial in primary biliary cirrhosis (PBC). Presently there is no satisfactory simple scoring system analysing them reliably. We elaborated a semi-quantitative scoring system that assesses fibrosis, lymphocytic interface hepatitis (LIH) and ductopenia, separately. This study was aimed to evaluate its intra/interobserver reproducibility and its correlation with the main biochemical data. METHODS: Liver biopsies from 33 consecutive newly diagnosed PBC patients were independently analysed by five liver pathologists. Fibrosis was classified into five stages (portal/periportal fibrosis/few septa/numerous septa/cirrhosis) and LIH into four grades. The bile duct ratio (BDR), i.e. ratio of the number of portal tracts with ducts to total number of portal tracts, Ludwig's and Scheuer's stages were evaluated. Intra and interobserver agreements were assessed. Histological results were correlated to the biochemical data. RESULTS: Most patients had an early disease on clinical and biological parameters. The biopsies measured 23 mm on average (range 12 - 40 mm). Intraobserver reproducibility was substantial for fibrosis (κ = 0.68), LIH (κ = 0.69) and BDR (ICC = 0.69). Interobserver agreement for fibrosis was fair with the 5-class system (κ = 0.36), moderate with a 4-class system (κ = 0.56). moderate for LIH (κ = 0.59) and BDR (ICC = 0.50). Ludwig's and Scheuer's staging showed a fair interobserver agreement (κ = 0.32, κ = 0.31 respectively). Our system showed better correlations with biochemistry than Ludwig's and Scheuer's systems did. CONCLUSIONS: This simple scoring system, assessing fibrosis, LIH and BDR separately, has a substantial intraobserver and a moderate interobserver reproducibility. Its prognostic relevance has to be evaluated.

Core needle versus standard needle for endoscopic ultrasound-guided biopsy of solid pancreatic masses: a randomized crossover study.

BACKGROUND AND STUDY AIMS: A new core biopsy needle for endoscopic ultrasound (EUS)-guided sampling has recently been developed. The aim of this prospective multicenter study was to compare this needle with a standard needle in patients with solid pancreatic masses. PATIENTS AND METHODS: Consecutive patients with solid pancreatic masses referred to 17 centers for EUS-guided sampling were included. Each patient had two passes with a standard 22G needle and a single pass with a 22G core needle performed in a randomized order. Samples from both needles were separately processed for liquid-based cytology and cell-block preparation and were assessed independently by two blinded expert pathologists. The primary endpoint was the accuracy of the detection of malignancy. The reference standard was based on further cytohistological analysis obtained under ultrasound or computed tomography scanning, endoscopic or surgical guidance, and/or by clinical follow-up with repeated imaging examinations for at least 12 months. The secondary endpoints were the rate of technical failure and the quality of the cytohistological samples obtained. RESULTS: Of the 80 patients included (49 men; mean age 67.1 ±â€Š11.1), 87.5 % had final malignant diagnoses (adenocarcinoma n = 62, 77.5 %). There was no difference between the needles in diagnostic accuracy (standard needle 92.5 % vs. core needle 90 %; P = 0.68) or technical failure. Both pathologists found the overall sample quality significantly better for the standard needle (expert 1, P = 0.009; expert 2, P = 0.002). CONCLUSIONS: The diagnostic accuracy of EUS sampling for solid pancreatic masses using standard and core needles seems comparable but with a better overall histological sample quality for the former. ClinicalTrial.gov identifier: NCT01479803.

Metastatic hepatic epithelioid hemangio-endothelioma: long-term response to sunitinib malate.

BACKGROUND: Epithelioid hemangio-endothelioma (EHE) is a rare malignant tumor of vascular origin that electively metastasizes to lungs and liver. CASE REPORT: We report the case of a 51-year-old woman with metastatic and progressive EHE of the liver. She was successfully treated with daily administration of sunitinib malate, an oral multi-target tyrosine kinase inhibitor, which particularly targets vascular endothelial growth factor (VEGF) receptors. Stabilization has lasted 6 years. We discuss the rationale for using antiangiogenic treatment for EHE. CONCLUSION: This case adds to a growing body of evidence that suggests that antiangiogenic agents should be considered in patients who present with advanced EHE.

Gastrojejunal Anastomosis Exclusively Using the "NOTES" Technique in Live Pigs: A Feasibility and Reliability Study.

INTRODUCTION: Natural orifice transluminal endoscopic surgery (NOTES) could reduce procedure-associated morbidity and mortality. The aim of this study was to determine the feasibility of performing a simple model of gastrojejunal anastomosis in a living porcine model exclusively using NOTES. METHODS: It was a prospective experimental animal study concerning pigs weighing between 25 and 30 kg. Endoscopies were performed using a double-channel gastroscope. A preliminary phase allowed for the development of the technique on 3 animals that were immediately euthanized. The experimental phase included the implementation of a gastrojejunal anastomosis in 9 animals. Antibiotic therapy was continued for 7 days with gradual feeding. Surviving animals were euthanized after 3 weeks. Anastomosis permeability in each animal was confirmed by opacification, endoscopy, and histopathological analysis. The main outcome measurements were the feasibility and animal survival at 3 weeks postsurgery. RESULTS: The entire procedure was performed on 9 animals (4 males and 5 females). Anastomosis required 4.7 ± 1.2 stitches (range 4-7). The average total length of the procedure was 143 ± 50.8 minutes (range 87-225 minutes). One bleeding, 2 suture dehiscences, and a poor stomach incision were the immediate complications endoscopically resolved. At 3 weeks, 5 animals had survived. Three animals died as a result of anastomotic leakage confirmed at necropsy and histopathology. In the surviving animals, histology confirmed permeable anastomoses with collagen scar tissue and continuity of the mucosa and mucosa muscle layers. CONCLUSION: Successful gastrojejunal anastomosis by NOTES is technically feasible but is subject to a learning curve.

Preventive cancer stem cell-based vaccination reduces liver metastasis development in a rat colon carcinoma syngeneic model.

Cancer stem cells (CSCs) represent a minor population of self-renewing cancer cells that fuel tumor growth. As CSCs are generally spared by conventional treatments, this population is likely to be responsible for relapses that are observed in most cancers. In this work, we analyzed the preventive efficiency of a CSC-based vaccine on the development of liver metastasis from colon cancer in a syngeneic rat model. We isolated a CSC-enriched population from the rat PROb colon carcinoma cell line on the basis of the expression of the aldehyde dehydrogenase-1 (ALDH1) marker. Comparative analysis of vaccines containing lysates of PROb or ALDH(high) cells by mass spectrometry identifies four proteins specifically expressed in the CSC subpopulation. The expression of two of them (heat shock protein 27-kDa and aldose reductase) is already known to be associated with treatment resistance and poor prognosis in colon cancer. Preventive intraperitoneal administration of vaccines was then performed before the intrahepatic injection of PROb cancer cells. While no significant difference in tumor occurrence was observed between control and PROb-vaccinated groups, 50% of the CSC-based vaccinated animals became resistant to tumor development. In addition, CSC-based vaccination induced a 99.5% reduction in tumor volume compared to the control group. To our knowledge, this study constitutes the first work analyzing the potential of a CSC-based vaccination to prevent liver metastasis development. Our data demonstrate that a CSC-based vaccine reduces efficiently both tumor volume and occurrence in a rat colon carcinoma syngeneic model.

Immunohistochemical markers on needle biopsies are helpful for the diagnosis of focal nodular hyperplasia and hepatocellular adenoma subtypes.

Phenotypic identification of focal nodular hyperplasia (FNH) and hepatocellular adenoma (HCA) subtypes using immunohistochemical markers has been developed from their molecular characteristics. Our objective was to evaluate the sensitivity of these markers in the definitive diagnosis of these lesions by core needle biopsies. A total of 239 needle biopsies paired with their surgical resection specimen (group A) or without an associated resection specimen (group B) were reviewed. Using a step-by-step algorithm after standard staining, appropriate immunostaining analyses were performed to determine the certainty of diagnosis of FNH, HNF1α-inactivated HCA, inflammatory HCA, ß-catenin-activated HCA, or unclassified HCA. The diagnosis of FNH was certain or probable on routine stains in 53% of needle biopsies of group A, whereas after glutamine synthetase staining, the diagnosis was certain in 86.7% as compared with 100% on the corresponding surgical specimen (P=0.04). In needle biopsies of group A, the diagnosis of HCA was certain on routine stains in 58.6% as compared with 94.3% on surgical specimens. After specific immunostaining, diagnosis was established on biopsies with 74.3% certainty, including all HCA subtypes, with similar distribution in surgical specimens. For each "certain diagnosis" paired diagnostic test (biopsy and surgical specimen), a positive correlation was observed (P<0.001). No significant difference was observed between groups A and B for FNH (P=0.714) or for HCA subtypes (P=0.750). Compared with surgical specimens, immunohistochemical analysis performed on biopsies allowed the discrimination of FNH from HCA and the identification of HCA subtypes with good performance.

The pig as a preclinical model for intestinal ischemia-reperfusion and transplantation studies.

Small bowel transplantation has become an established procedure for treatment of irreversible intestinal failure. In this procedure, primary ischemia and reperfusion is inevitable and will lead to some level of tissue injury. Both clinical and experimental data demonstrate that events occurring at the time of transplantation, called ischemia reperfusion injury (IRI), may have deleterious short- and long-term effects, manifesting as increased episodes of acute rejection and chronic allograft dysfunction. Recently, the acute phase of IRI has been increasingly viewed as part of the innate immune response to the lack of vascular perfusion and oxygen. Research on intestinal IRI that aims to understand its mechanisms and the means to reduce its impact on morbidity and mortality related to intestinal transplantations is considered important because a link has been suggested between innate immunity, adaptive immune responses and organ regeneration, and thus long-term graft function. This article provides an overview of porcine models commonly used to study intestinal reperfusion injury and to evaluate intestinal transplant protocols. It also updates the current knowledge obtained from this model, establishing the pig as a reference standard in intestinal transplantation research.

Regular coffee but not espresso drinking is protective against fibrosis in a cohort mainly composed of morbidly obese European women with NAFLD undergoing bariatric surgery.

BACKGROUND & AIMS: The aim of this study was to determine the influence of coffee and other caffeinated drinks on liver fibrosis of severely obese European patients. METHODS: A specific questionnaire exploring various types of coffee (regular filtrated coffee and espresso), caffeinated drinks, and chocolate was filled in by 195 severely obese patients. All patients had liver biopsies that were analyzed according to the NASH Clinical Research Network Scoring System. Univariate and multivariate analyses of significant fibrosis were performed. RESULTS: Caffeine came mainly from coffee-containing beverages (77.5%). Regular coffee and espresso were consumed in 30.8% and 50.2% of the patients, respectively. Regular coffee, espresso, and total caffeine consumption was similar between patients with and without NASH. While consumption of espresso, caffeinated soft drinks, and chocolate was similar among patients, with respect to the level of fibrosis, regular coffee consumption was lower in patients with significant fibrosis (F ≥2). According to logistic regression analysis, consumption of regular coffee was an independent protective factor for fibrosis (OR: 0.752 [0.578-0.980], p=0.035) in a model including level of AST (OR: 1.04 [1.004-1.076], p=0.029), presence of NASH (OR: 2.41 [1.007-5.782], p=0.048), presence of the metabolic syndrome (NS), and level of HOMA-IR (NS). Espresso, but not regular coffee consumption was higher in patients with lower HDL cholesterol level, higher triglyceride level, and the metabolic syndrome. CONCLUSIONS: Consumption of regular coffee but not espresso is an independent protective factor for liver fibrosis in severely obese European patients.

The osteopontin level in liver, adipose tissue and serum is correlated with fibrosis in patients with alcoholic liver disease.

BACKGROUND: Osteopontin (OPN) plays an important role in the progression of chronic liver diseases. We aimed to quantify the liver, adipose tissue and serum levels of OPN in heavy alcohol drinkers and to compare them with the histological severity of hepatic inflammation and fibrosis. METHODOLOGY/PRINCIPAL FINDINGS: OPN was evaluated in the serum of a retrospective and prospective group of 109 and 95 heavy alcohol drinkers, respectively, in the liver of 34 patients from the retrospective group, and in the liver and adipose tissue from an additional group of 38 heavy alcohol drinkers. Serum levels of OPN increased slightly with hepatic inflammation and progressively with the severity of hepatic fibrosis. Hepatic OPN expression correlated with hepatic inflammation, fibrosis, TGFß expression, neutrophils accumulation and with the serum OPN level. Interestingly, adipose tissue OPN expression also correlated with hepatic fibrosis even after 7 days of alcohol abstinence. The elevated serum OPN level was an independent risk factor in estimating significant (F ≥ 2) fibrosis in a model combining alkaline phosphatase, albumin, hemoglobin, OPN and FibroMeter® levels. OPN had an area under the receiving operator curve that estimated significant fibrosis of 0.89 and 0.88 in the retrospective and prospective groups, respectively. OPN, Hyaluronate (AUROC: 0.88), total Cytokeratin 18 (AUROC: 0.83) and FibroMeter® (AUROC: 0.90) estimated significance to the same extent in the retrospective group. Finally, the serum OPN levels also correlated with hepatic fibrosis and estimated significant (F ≥ 2) fibrosis in 86 patients with chronic hepatitis C, which suggested that its elevated level could be a general response to chronic liver injury. CONCLUSION/SIGNIFICANCE: OPN increased in the liver, adipose tissue and serum with liver fibrosis in alcoholic patients. Further, OPN is a new relevant biomarker for significant liver fibrosis. OPN could thus be an important actor in the pathogenesis of this chronic liver disease.

GNAS-activating mutations define a rare subgroup of inflammatory liver tumors characterized by STAT3 activation.

BACKGROUND & AIMS: Mosaic G-protein alpha-subunit (GNAS)-activating mutations are responsible for the McCune-Albright (MCA) syndrome. This oncogene that activates the adenylate cyclase is also mutated in various tumor types leading to the accumulation of cyclic-AMP. Identification of a hepatocellular adenoma (HCA) in two MCA patients led us to search for GNAS activation in benign and malignant hepatocellular carcinogenesis. METHODS: GNAS mutations were screened by sequencing 164 HCA, 245 hepatocellular carcinoma (HCC), and 17 fibrolamellar carcinomas. Tumors were characterized by quantitative RT-PCR, gene mutation screening and pathological reviewing. The consequences of wild type and mutant GNAS expression were analyzed in hepatocellular cell lines. RESULTS: A somatic GNAS-activating mutation was identified in 5 benign tumors and in 2 HCC. In benign tumors, GNAS mutations were exclusive from HNF1A, CTNNB1, and IL6ST mutations whereas one HCC demonstrated both CTNNB1 and GNAS mutations. Quantitative RT-PCR showed an activation of the IL-6 and interferon pathways in GNAS-mutated tumor tissues. Accordingly, pathological reviewing identified in GNAS-mutated tumors an inflammatory phenotype characterized by fibrosis and STAT3 activation. We further demonstrated in HCC cell lines that GNAS mutant expression induced inflammatory response and STAT3 activation. CONCLUSIONS: We identified for the first time the association between two rare diseases, MCA syndrome and HCA occurrence, but also that somatic GNAS-activating mutations in sporadic benign and malignant liver tumors are characterized by an inflammatory phenotype. These results showed a cross-talk between cyclic-AMP and JAK/STAT pathways in liver tumors and they reinforce the role of STAT3 activation in liver tumorigenesis.