T. Roskams

Pharmacological IKK2 inhibition blocks liver steatosis and initiation of non-alcoholic steatohepatitis

Background: Non-alcoholic-steatohepatitis (NASH) leading to fibrosis, end-stage cirrhosis and hepatocellular carcinoma is an increasing health problem in the Western world. Thus, the need for new therapeutic approaches is increasing. IKK2 plays a key role in the development of NASH by mediating inflammation and insulin resistance. Aim: Here the beneficial effects of a pharmacological IKK2 inhibitor (AS602868) on initial stages of NASH progression were tested. Methods: Mice were fed with a high sucrose diet (HSD) and daily-administered AS602868 and vehicle. The impact of AS602868 on NASH progression was studied using biochemical, histological and molecular markers. Results: AS602868 treatment prevented HSD-induced weight gain and visceral fat accumulation. In adipose tissue, AS602868-treated mice exhibited a lower degree of infiltrated macrophages along with reduced proinflammatory cytokine production. Further analysis demonstrated that AS602868 treatment efficiently inhibited nuclear factor (NF)-κB activation in liver non-parenchymal cells and as a consequence attenuated the inflammatory response in the liver. Accordingly, in HSD/AS602868 mice, liver and adipose tissue adiponectin levels remained at levels comparable with those of control chow-fed mice, while they were decreased in HSD/vehicle animals. Additionally, AS602868 improved lipid β-oxidation mediated by peroxisome proliferator-activated receptor (PPAR) α and PPARγ. Systemic pharmacological IKK2 inhibition by AS602868 treatment efficiently prevented liver steatosis and inflammation, and improved antioxidant response. All this contributed to attenuation of NASH progression as evidenced by lower hepatocyte apoptosis and early stages of liver fibrosis. Conclusion: The data demonstrate that AS602868-mediated IKK2 inhibition represents a new therapeutic approach to prevent dietary-induced NASH progression.

Characterisation of the hepatic progenitor cell compartment in normal liver and in hepatitis: an immunohistochemical comparison between dog and man.

The liver progenitor cell compartment in the normal canine liver and in spontaneous canine acute (AH) and chronic hepatitis (CH) was morphologically characterised and compared to its human equivalents. Immunohistochemistry was performed for cytokeratin-7 (CK7), human hepatocyte marker (Hep Par 1), multidrug resistance-associated protein-2 (MRP2), and breast cancer resistance protein (BCRP) on paraffin and frozen sections from canine and human tissues. Normal liver showed similar morphology and immunohistochemical reaction of the progenitor cell compartment/canal of Hering in man and dog. In addition, a ductular reaction, comparable in terms of severity, location and immunohistochemical characteristics, was observed in canine and human AH and CH. CK7 was a good marker for canine progenitor cells, including intermediate cells, which were positively identified in cases of AH and CH. In both species, BCRP was expressed in both hepatocytes and bile ducts of the normal liver, and in ductular reaction in AH and CH. MRP2 detected bile canalicular membranes in man and dog. These findings underline the similarities between canine and human liver reaction patterns and may offer mutual advantage for comparative research in human and canine spontaneous liver diseases.

654 A NEW CLASSIFICATION OF PRIMARY LIVER CARCINOMAS BASED ON THEIR POSSIBLE CELLULAR ORIGIN

universal sustained virological response (SVR), it is eagerly hoped that morbidity and mortality from hepatitis C virus (HCV) will soon disappear. At present, cirrhosis, the predominant risk factor for hepatocellular carcinoma (HCC), is increasing among patients with HCV as they become older and the duration of infection longer. We estimate the impact of DAAs with high SVR rates on the incidence of HCC in the population. Methods: Since the extent to which the risk of HCC decreases in patients with established cirrhosis achieving SVR remains poorly defined, we conducted a simulation experiment in which a cohort of 50 year-old subjects (n = 1,000) with compensated HCV cirrhosis (MELD=6) is followed for 20 years. In a viremic subject, the MELD score, HCC and mortality from end stage liver disease (ESLD) would increase progressively. Once SVR is achieved, MELD would stop increasing and the proportion at risk of HCC decrease over time. Results: The Table summarizes 20-year outcomes in the 50 year-old cohort based on SVR eliminating HCC risk in 3%/year.

682 APPARENT DIFFUSION COEFFICIENT DETERMINED TARGET RESPONSE AT DIFFUSION-WEIGHTED MRI IS AN INDEPENDENT PREDICTOR OF OUTCOME IN HEPATOCELLULAR CANCER PATIENTS TREATED WITH TRANSARTERIAL CHEMOEMBOLIZATION

Patients and Methods: Two hundred pairs of patients with cirrhosis and HCC and unrelated patients with cirrhosis alone were enrolled. Polymorphisms of TNFa −238, TNFa −308, and lymphotoxin (LT)a +252 were genotyped by the polymerase chain reaction with direct sequencing or restriction fragmented length polymorphism. TNF haplotypes were also analyzed. From routine laboratory data, the following surrogate markers associated with hepatic fibrosis were measured: platelet count, aspartate aminotransferase/alanine aminotransferase ratio, aspartate aminotransferase/platelet ratio index, Pohl score, and cirrhosis discriminant score. These fibrosis surrogate markers were analyzed with polymorphisms and haplotypes of TNF locus. Results: The frequencies of the variant genotypes and alleles of LTa +252 and TNFa −308 in patients with HCC were significantly higher than those in patients with cirrhosis alone. There was no such a difference in the TNFa −238 polymorphisms. Univariate analysis indicated that LTa +252 G/G genotype (odds ratio (OR) = 2.31) and TNFa −308 G/A genotype (OR=2.31) were significantly associated with HCC. Multivariate analysis indicated that LTa +252 G/G (OR=2.05, 95% confidence interval (CI), 1.20– 3.51), TNFa −308 G/A (OR=1.77, 95%CI, 1.02–3.07), and TNF haplotypes (AGA, OR=5.69; 95%CI, 1.90–17.10; GGA, OR=2.07; 95%CI, 1.18–3.63; and GGG, OR=1.51, 95%CI, 1.11–2.04) were independent risk factors for HCC. Among patients with cirrhosis and HCC, significant hepatic fibrosis was found between 71.4% and 93.5% of patients with variant TNF genotypes and between 54.4% and 86.8% of patients harboring TNF haplotypes (AGA, GAG and GGG). Multivariate analysis showed that factors associated with variant genotypes included cirrhosis with Child–Pugh C (OR=8.85; 95%CI, 3.08–35.64), serum a-fetoprotein >100ng/ml (OR=2.50; 95%CI, 1.23–5.06), and thrombocytopenia (OR=3.26; 95%CI, 1.14– 9.30). Conclusions: Patients with cirrhosis who carry the TNF genetic variants were correlated with advanced fibrosis and severe liver damage, which may contribute to a higher risk to HCC.

970 OCCURRENCE AND CLINICOPATHOLOGICAL RELEVANCE OF PROGNOSTIC MARKERS IN HEPATOCELLULAR CARCINOMA

The threshold annual incidence for efficacy of HCC surveillance in non-HBV liver cirrhosis has been established in 1.5%. Although alcoholic cirrhosis is clearly a risk factor for HCC, the incidence of the tumour in this population is not accurately known. Aim: To determine the annual incidence of HCC in a cohort of patients with alcoholic cirrhosis followed prospectively and to define groups with different risk of tumour development. Methods: We evaluated 450 consecutive patients with alcoholic liver cirrhosis (369 men, mean age 53.9±7.4 years) included in a surveillance program for HCC detection (mean follow-up 59±49 months). All patients were Child–Pugh class A/B. The diagnosis of cirrhosis was supported by liver biopsy in 140 patients and was based on clinical-biological criteria in the rest. Alcoholic etiology was established by history of alcohol consumption and the exclusion of other etiologies. The first 5 years after inclusion in the program were considered to define potential risk factors. Nineteen demographic, clinical and laboratory variables were analysed. Results: During the overall follow-up, 62 patients developed HCC. The annual incidence was 2.6% and the 10-years cumulative incidence was 25.2%. In the first 5 years after inclusion in the program, 43 patients developed HCC. In univariate analysis, age > 58 years, platelets 2mg/dl, albumin 58 (OR 2.91, 95%CI 1.29– 6.57) and platelets <125×103/mm3 (OR 2.40, 95%CI 1.30–4.46) were independently associated with an increased risk of HCC. These two variables allowed us to define 3 different risk groups. The annual incidence of HCC in the group without any of these two factors (n = 109), with one of them (n=249) or with both (n =87) was 0.6%, 2.8% and 5.3% respectively (p < 0.0001). Conclusions: The annual incidence of HCC in patients with alcoholic cirrhosis Child–Pugh class A/B is about 2.5%. Two simple variables, age and platelets, can be used to distribute the patients in different risk groups for HCC development over the next 5 years. A surveillance program for early detection of HCC is probably not justifiable in the low-risk group.

[163] CORRELATION BETWEEN HEPATOCYTE AND HEPATIC PROGENITOR CELL REGENERATION AND MODEL FOR END STAGE LIVER DISEASE (MELD) SCORE IN ACUTE SEVERE LIVER IMPAIRMENT

XIXth Belgian Week of Gastroenterology 2007

[70] DELETION OF NEMO/IKK-G IN LIVER PARENCHYMAL CELLS CAUSES STEATOHEPATITIS AND HEPATOCELLULAR CARCINOMA

The IkB kinase (IKK) subunit NEMO/IKKg is essential for activation of the transcription factor NF-kB,which regulates cellular responses to inflammation. The function of NEMO in the adult liver remainselusive. Here we show that ablation of NEMO in liver parenchymal cells caused the spontaneousdevelopmentofhepatocellularcarcinomainmice.Tumordevelopmentwasprecededbychronicliverdisease resembling human nonalcoholic steatohepatitis (NASH). Antioxidant treatment and geneticablationofFADDdemonstratedthatdeathreceptor-mediatedandoxidativestress-dependentdeathof NEMO-deficient hepatocytes triggered disease pathogenesis in this model. These results revealthat NEMO-mediated NF-kB activation in hepatocytes has an essential physiological function toprevent the spontaneous development of steatohepatitis and hepatocellular carcinoma, identifyingNEMO as a tumor suppressor in the liver.