Chronic liver diseases are characterized by the expansion of ductular reaction (DR) cells and the expression of liver progenitor cell (LPC) markers. In alcoholic hepatitis (AH), the degree of DR expansion correlates with disease progression and short-term survival. However, little is known about the biological properties of DR cells, their impact on the pathogenesis of human liver disease, and their contribution to tissue repair. In this study, we have evaluated the transcriptomic profile of DR cells by laser capture microdissection in patients with AH and assessed its association with disease progression. The transcriptome analysis of cytokeratin 7-positive (KRT7+ ) DR cells uncovered intrinsic gene pathways expressed in DR and genes associated with alcoholic liver disease progression. Importantly, DR presented a proinflammatory profile with expression of neutrophil recruiting C-X-C motif chemokine ligand (CXC) and C-C motif chemokine ligand chemokines. Moreover, LPC markers correlated with liver expression and circulating levels of inflammatory mediators such as CXCL5. Histologically, DR was associated with neutrophil infiltration at the periportal area. In order to model the DR and to assess its functional role, we generated LPC organoids derived from patients with cirrhosis. Liver organoids mimicked the transcriptomic and proinflammatory profile of DR cells. Conditioned medium from organoids induced neutrophil migration and enhanced cytokine expression in neutrophils. Likewise, neutrophils promoted the proinflammatory profile and the expression of chemokines of liver organoids. Conclusion: Transcriptomic and functional analysis of KRT7+ cells indicate that DR has a proinflammatory profile and promote neutrophil recruitment. These results indicate that DR may be involved in the liver inflammatory response in AH, and suggest that therapeutic strategies targeting DR cells may be useful to mitigate the inflammatory cell recruitment in AH.

The Wnt/β-catenin pathway plays a key role in liver development, regeneration and tumorigenesis. Among human cancers tightly linked to abnormal Wnt/β-catenin signaling, hepatoblastoma (HB) presents with the highest rate (50–90%) of β-catenin mutations. HB is the most common malignant tumor of the liver in childhood. This embryonic tumor differs from hepatocellular carcinoma by the absence of viral etiology and underlying liver disease, and by distinctive morphological patterns evoking hepatoblasts, the bipotent precursors of hepatocytes and cholangiocytes. Recent studies of the molecular pathogenesis of hepatoblastoma have led to identify two major tumor subclasses resembling early and late phases of prenatal liver development and presenting distinctive chromosomal alterations. It has been shown that the molecular signature of Wnt/β-catenin signaling in hepatoblastoma is mainly imposed by liver context, but differs according to developmental stage. Finally, the differentiation stage of tumor cells strongly influences their invasive and metastatic properties, therefore affecting clinical behavior.

The preliminary analysis of this study shows that adding EBL to pharmacological treatment does not significantly reduce the incidence of rebleeding episodes and does not improve survival in patients with cirrhosis treated after an episode of variceal bleeding, although it reduces the frequency of variceal rebleeding.However, non-variceal rebleeding was more common in pts treated with EBL, who also had more frequently complications requiring hospital admission.

Purpose: To allow the longitudinal investigation of molecular events associated with the progression of human hepatocellular carcinoma (HCC), we sought to develop a murine model by orthotopic implantation of tumor fragments obtained from patients diagnosed at early stage. Experimental Design: Tumor pieces (2 × 2 mm) were implanted on the liver surface of nu/nu mice. After xenograft growing, subsequent passages were performed to achieve long-term implant viability. Isolation of tumoral hepatocytes was done to establish new cell lines. HCC characteristics, proliferation rate, apoptotic index (terminal deoxynucleotidyl transferase-mediated nick end labeling), and expression of cell-cycle regulators (cyclins E and A, p21Cip1, p27Kip1, p16INK4a, pRb, and p53) were assessed by Western Blot and immunohistochemistry, to correlate them with tumor progression. Results: Five (50%) of the 10 primary HCCs resulted in small slow-growing liver implants. Three of them are viable after 48 months, whereas the remaining two survived for 15 and 13 months. Xenografts throughout passages exhibited a more aggressive phenotype with a poorer degree of differentiation, intense proliferation, moderate apoptosis, cell-cycle deregulation, p53 alterations, microvascular invasion, and dissemination. In one single passage, we observed critical growth delay, which was associated with significant p27kip1 overexpression. We established the anchor-free growing BCLC-9 cell line from one xenograft. This has gains of chromosomes 7, 5p, 6q, and 9q, is hepatitis B virus-DNA positive, does not secrete α-fetoprotein, and has TP53 missense mutations in codons 192 and 242. Conclusions: The orthotopic implantation of early HCC fragments in nude mice provides a useful model to investigate the mechanisms of human HCC evolution and to establish new cell lines.

Background/Aims: Alterations in p27(Kip1) (p27) and cyclin E (cycE) expression are found in tumors and are related to poor prognosis. This study assesses the role of these cell cycle regulators in the development of recurrence after surgical resection in 46 cirrhotic patients (age: 61.3 +/- 7 years, 30 males, 44 Child-Pugh's A, 30 HCV-positive) with small hepatocellular carcinoma (HCC, size: 3.1 +/- 1.5 cm, 40 solitary at pathological examination).Methods: p27 and cycE expression in tumoral and non-tumoral liver were analyzed by Western blot (WB). p27 was also assessed by immunohistochemistry (IHC).Results: Tumor p27 underexpression (50% decreased vs. non-tumoral liver) occurred in 12 cases. Throughout follow-up, 26 patients developed recurrence, which was significantly higher in patients with p27 underexpression than in those without (3-year recurrence: 80 vs. 44%, respectively, P = 0.026). IHC showed concordant inverse findings: 13 tumors showed high p27 staining that was related to lower recurrence rate (P = 0.019). Multivariate analysis identified p27 measured by WB as an improved predictor of recurrence (OR: 3.09, 95% CI: 1.26-7.08, P = 0.016). By contrast, cycE, increased in 66% of the tumors, had no. impact on recurrence but was associated to poor differentiation (P = 0.015) and microvascular invasion (P = 0.016).Conclusions: p27 underexpression is frequent in relatively early stages of HCC and constitutes an independent predictor of recurrence after surgical resection. (C) 2003 European Association for the Study of the Liver. Published by Elsevier Science B.V. All rights reserved.

En une dizaine d'années, le diesel a connu un développement spectaculaire sur les marchés automobile français et européen et pourrait atteindre, en 1995, la moitié des immatriculations de véhicules particuliers en France et le quart en Europe de l'Ouest. Cette situation n'est évidemment pas sans poser de problèmes. Problèmes environnementaux puisque le moteur diesel est une source plus importante d'émissions d'oxydes d'azote et de particules que le convertisseur essence, mais également au niveau de l'industrie du raffinage qui, en France, n'est plus en mesure de satisfaire la demande en gazole. De plus, à compter du 1er octobre 1996, la teneur en soufre du gazole routier ne devra pas excéder 0,05 %, conformément aux nouvelles spécifications européennes. Cette perspective de production de carburants fortement désulfurés va affecter directement l'équilibre en hydrogène de la raffinerie et donc les autoconsommations et les émissions de CO2. L'objectif de cette étude est de mesurer l'impact sur l'environnement d'une réduction de la teneur en soufre des gazoles de 0,3 à 0,05 %. Le bilan est réalisé sur l'ensemble de la filière énergétique, depuis l'extraction du pétrole jusqu'à la combustion du carburant dans le moteur. Les gains et les pertes en termes de pollution locale ou globale sont évalués suivant la nature de l'hydrogène utilisé (oxydation partielle de résidus sous vide ou de charbon, reformage à la vapeur de gaz naturel ou de naphta électrolyse) et la nature de la charge à traiter (gazole straight run ou light cycle oil) lors de l'hydrodésulfuration.