M. Strazzabosco

Genome-wide meta-analyses identify three loci associated with primary biliary cirrhosis

A genome-wide association screen for primary biliary cirrhosis risk alleles was performed in an Italian cohort. The results from the Italian cohort replicated IL12A and IL12RB associations, and a combined meta-analysis using a Canadian dataset identified newly associated loci at SPIB (P = 7.9 × 10−11, odds ratio (OR) = 1.46), IRF5-TNPO3 (P = 2.8 × 10−10, OR = 1.63) and 17q12-21 (P = 1.7 × 10−10, OR = 1.38).

Is the risk of neoplastic recurrence increased after prescribing direct-acting antivirals for HCV patients whose HCC was previously cured?

Variable Total cohort (n = 31) (%) Antitumoral treatment Resection 13 (42%) Resection and percutaneous ablation 1 (3%) Resection and TACE and percutaneous ablation 1 (3%) Resection and TACE 3 (10%) Percutaneous ablation and TACE 3 (10%) Percutaneous ablation 6 (19%) TACE 4 (13%) Worst BCLC stage prior to DAA therapy BCLC-0 8 (26%) BCLC-A1 4 (13%) BCLC-A2 9 (29%) BCLC-A3 2 (6%) BCLC-A4 3 (10%) BCLC-B 4 (13%) BCLC-C 1 (3%) Bilirubin (mean ± SD) 1.1 ± 0.7 Albumin (mean ± SD) 3.7 ± 0.5 Prothrombin time (INR) (mean ± SD) 1.1 ± 0.1 Alanine aminotransferase (mean ± SD) 71 ± 30 Pre-DAA HCV RNA levels (Log10), (median, range) (IU/ml) 5.6 (3.8-7.5) Pre-DAA serum AFP levels (median, range) (ng/ml) 10 (2-278) Treatment regimens SOF/LDV ± RBV for 12 or 24 weeks 15 (48%) SIM/SOF for 12 weeks 6 (19%) SOF/DCV ± RBV for 24 weeks 2 (6%) PrOD or the 3D regimen ± RBV for 12 or 24 weeks 3 (9.6%) SOF/RBV for 24 weeks 3 (9.6%) End of treatment response 31 (100%) Post-DAA serum AFP levels (median, range) (ng/ml) 6 (1-44) Interval between start of DAA therapy and last radiological assessment (months) (median, percentile 25-75) 8 (5-10.9)

Notch signaling in hepatocellular carcinoma: guilty in association!

Notch signaling is a complex, highly conserved mechanism, originally discovered as critical regulator of cell fate determination during development in several tissues and organs.1,2 Activation of Notch may stimulate cells either to undergo a phenotypic switch or to maintain the original cell phenotype by preventing further differentiation,3 Notch is also involved in establishing organ-specific stem cell niches necessary for epithelial tissue homeostasis.3,4 The Notch system encompasses 4 genes encoding for different membrane receptors (Notch 1, 2, 3, and 4), which are activated by their binding to 5 ligands (Jagged-1, Jagged-2, and Delta-like 1, 3, and 4).4 Cell-to-cell contact is a prerequisite for the activation of Notch signaling.3,4 Whereas Notch receptors are expressed by the “receiver” cell, ligands are expressed by the “transmitter” cell. This interaction leads to the proteolytic cleavage and subsequent nuclear translocation of the intracellular domain of Notch receptors (NICD). Once migrated into the nucleus, NICD associates with the nuclear protein of the RBP-Jκ family and transcriptionally activates several other transcriptional activators or repressors that act as critical regulators of cell differentiation, apoptosis, and proliferation4 (see drawing on the left side of Figure 1). NICD is then rapidly deactivated by phosphorylation and by proteosomal degradation. The signal is maintained through ligand-induced proteolytic supply of new NICD.

Insulin resistance and necroinflammation drives ductular reaction and epithelial-mesenchymal transition in chronic hepatitis C

Objective To study the mechanism(s) linking insulin resistance (IR) to hepatic fibrosis and the role of the epithelial component in tissue repair and fibrosis in chronic hepatitis C (CHC). Design Prospective observational study. Setting Tertiary care academic centre. Patients 78 consecutive patients with CHC. Main outcome measures IR, calculated by the oral glucose insulin sensitivity during oral glucose tolerance test; necroinflammatory activity and fibrosis, defined according to Ishaks score; steatosis, graded as 0 (<5% of hepatocytes), 1 (5–33%), 2 (33–66%) and 3 (>66%). To evaluate the role of the epithelial component in tissue repair and fibrosis, the expansion of the ductular reaction (DR) was calculated by keratin-7 (CK7) morphometry. Nuclear expression of Snail, downregulation of E-cadherin and expression of fibroblast specific protein-1 (FSP1) and vimentin by CK7-positive cells were used as markers of epithelial-mesenchymal transition in DR elements. Results IR, the degree of necroinflammation and expansion of the DR (stratified as reactive ductular cells (RDCs), hepatic progenitor cells and intermediate hepatobiliary cells according to morphological criteria) were all associated with the stage of fibrosis. Nuclear Snail expression, E-cadherin downregulation and vimentin upregulation were observed in RDCs. By dual immunofluorescence for CK7 and FSP1, the number of RDCs undergoing epithelial-mesenchymal transition progressively increased together with the necroinflammatory score. By multivariate analysis, total inflammation and insulin resistance were the only factors significantly predicting the presence of advanced fibrosis (Ishak score ≥3) and the expansion of RDCs. Conclusion This study indicates that IR is associated with the degree of necroinflammatory injury in CHC and contributes to hepatic fibrosis by stimulating the expansion of RDCs that express epithelial-mesenchymal transition markers.

Cholangiocarcinoma in Italy: A national survey on clinical characteristics, diagnostic modalities and treatment. Results from the "Cholangiocarcinoma" committee of the Italian Association for the Study of Liver disease.

BACKGROUNDnVery few studies assessed cholangiocarcinoma clinical characteristics.nnnAIMnTo evaluate the clinical characteristics of intra-hepatic (IH) and extra-hepatic (EH)-CCA.nnnMETHODSnWe performed a national survey based on a questionnaire.nnnRESULTSn218 cholangiocarcinomas were observed (47% EH-CCA, 53% IH-CCA) with an age at the diagnosis higher for EH-CCA. Coexistence of cirrhosis or viral cirrhosis was more frequent in IH-CCA than EH-CCA. An incidental asymptomatic presentation occurred in 28% of IH-CCA vs 4% EH-CCA whilst, 74% EH-CCA vs 28% IH-CCA presented with jaundice. 91% of IH-CCA presented as a single intra-hepatic mass, whilst 50% of EH-CCA was peri-hilar. In the diagnostic work-up, 70% of all cholangiocarcinoma cases received at least 3 different imaging procedures. Tissue-proven diagnosis was obtained in 80% cholangiocarcinoma. Open surgery with curative intent was performed in 45% of IH-CCA and 29% EH-CCA. 18% IH-CCA vs 4% EH-CCA did not received treatment.nnnCONCLUSIONSnIn Italy IH-CCA is managed as frequently as EH-CCA. In comparison to EH-CCA, IH-CCA occurs at younger age and is more frequently associated with cirrhosis and with an incidental asymptomatic presentation. In contrast, most EH-CCAs are jaundiced at the diagnosis. Cholangiocarcinoma diagnostic management is cost- and time-consuming with curative surgical treatment applicable more frequently in IH-CCA.

Advances in familial and congenital cholestatic diseases. Clinical and diagnostic implications.

Recent progress in liver cell biology and molecular genetics revealed that a number of familial and congenital cholestatic disorders are caused by mutations in genes coding for hepatobiliary-transporter or for signalling proteins involved in morphogenesis. The status of the field is reviewed in the light of its impact on current diagnostic and clinical practice. The heterogeneous progressive familial intrahepatic cholestasis can now be separated into different genetic diseases. FIC1-defective progressive familial intrahepatic cholestasis (previously Byler disease) is determined by mutations in the FIC1 gene, coding for P-type ATPases of unknown physiological function, while a second form (bile salt export pump defective progressive familial intrahepatic cholestatis) is caused by a defective function of the canalicular bile salt export pump. Furthermore, a group of progressive familial intrahepatic cholestasis patients with high serum gamma glutamyltranspeptidase have mutations in the gene (PGY3) coding for the MDR3 protein, a canalicular ATP-dependent phopshatidylcholine translocator. Recurrent intrahepatic cholestasis (previously benign recurrent cholestasis), is also linked to specific mutations in the FIC1 gene. Finally, in Alagille syndrome, mutations in the JAG1 gene cause deficiency Jagged 1, a ligand for Notch 1, a receptor determining cell fate during early embryogenesis. Diagnosis of Alagille syndrome, a condition that should be suspected in all patients with unexplained cholestasis, will thus be confirmed by genetic analysis for mutations of JAG1. In children with cholestasis and low serum bile acid levels, an inborn error of bile acid synthesis should be excluded by urinary bile acid analysis by means of fast atom bombardment-ionization mass-spectrometry. In contrast, in children with cholestasis and high serum bile acid concentrations, a high serum gamma glutamyltranspeptidase value would indicate MDR3 deficiency, which should be excluded through biliary phospholipid determination and genetic analysis of PGY3 gene. Finally, in those children with cholestasis, high serum bile acids and low gamma glutamyltranspeptidase activity, analysis of mutation in FIC1 and bile salt export pump genes may lead to the diagnosis of progressive familial intrahepatic cholestasis either from bile salt export pump or FIC1 deficiency.

Resveratrol impairs glioma stem cells proliferation and motility by modulating the wnt signaling pathway

Glioblastoma multiforme (GBM) is a grade IV astrocytoma and the most common form of malignant brain tumor in adults. GBM remains one of the most fatal and least successfully treated solid tumors: current therapies provide a median survival of 12–15 months after diagnosis, due to the high recurrence rate. Glioma Stem Cells (GSCs) are believed to be the real driving force of tumor initiation, progression and relapse. Therefore, better therapeutic strategies GSCs-targeted are needed. Resveratrol is a polyphenolic phytoalexin found in fruits and vegetables displaying pleiotropic health benefits. Many studies have highlighted its chemo-preventive and chemotherapeutic activities in a wide range of solid tumors. In this work, we analyzed the effects of Resveratrol exposure on cell viability, proliferation and motility in seven GSC lines isolated from GBM patients. For the first time in our knowledge, we investigated Resveratrol impact on Wnt signaling pathway in GSCs, evaluating the expression of seven Wnt signaling pathway-related genes and the protein levels of c-Myc and β-catenin. Finally, we analyzed Twist1 and Snail1 protein levels, two pivotal activators of epithelial-mesenchymal transition (EMT) program. Results showed that although response to Resveratrol exposure was highly heterogeneous among GSC lines, generally it was able to inhibit cell proliferation, increase cell mortality, and strongly decrease cell motility, modulating the Wnt signaling pathway and the EMT activators. Treatment with Resveratrol may represent a new interesting therapeutic approach, in order to affect GSCs proliferation and motility, even if further investigations are needed to deeply understand the GSCs heterogeneous response.

Molecular mechanisms driving cholangiocarcinoma invasiveness: an overview

The acquisition of invasive functions by tumor cells is a first and crucial step toward the development of metastasis, which nowadays represents the main cause of cancer-related death. Cholangiocarcinoma (CCA), a primary liver cancer originating from the biliary epithelium, typically develops intrahepatic or lymph node metastases at early stages, thus preventing the majority of patients from undergoing curative treatments, consistent with their very poor prognosis. As in most carcinomas, CCA cells gradually adopt a motile, mesenchymal-like phenotype, enabling them to cross the basement membrane, detach from the primary tumor, and invade the surrounding stroma. Unfortunately, little is known about the molecular mechanisms that synergistically orchestrate this proinvasive phenotypic switch. Autocrine and paracrine signals (cyto/chemokines, growth factors, and morphogens) permeating the tumor microenvironment undoubtedly play a prominent role in this context. Moreover, a number of recently identified signaling systems are currently drawing attention as putative mechanistic determinants of CCA cell invasion. They encompass transcription factors, protein kinases and phosphatases, ubiquitin ligases, adaptor proteins, and miRNAs, whose aberrant expression may result from either stochastic mutations or the abnormal activation of upstream pro-oncogenic pathways. Herein we sought to summarize the most relevant molecules in this field and to discuss their mechanism of action and potential prognostic relevance in CCA. Hopefully, a deeper knowledge of the molecular determinants of CCA invasiveness will help to identify clinically useful biomarkers and novel druggable targets, with the ultimate goal to develop innovative approaches to the management of this devastating malignancy.

EASL Recognition Awardee 2013: Professor Jesus Prieto

During the 2013 International Liver Congress in Amsterdam, EASL recognized the career and achievements of Professor Jesus Prieto. Hepatologists from all over the world celebrated the liver scholar, scientist, mentor, academic leader, physician and, for many of us, the friend. We recognize somebody because they have given testimony: Prof. Jesus Prieto showed us how to enjoy the richness of academic life through the interaction with our students, colleagues and patients, and how enthusiasm and curiosity can bring us into a dimension beyond biology and mechanisms. Jesus Prieto is Professor of Medicine at the University of Navarra, and Consultant of Medicine at the University Clinic. He has held leadership roles in several national and international scientific societies and has received a number of international awards and honors. He has published hundreds of peer-reviewed highly quoted papers in the fields of immune-mediated liver disease, biliary diseases, and gene therapy of the liver. Prof. Prieto received his MD degree at the University of Valladolid (Spain), where he specialized in Internal Medicine and Gastroenterology. In 1972 Jesus, at that time an Assistant Professor, moved to London where he worked as a post-doctoral fellow with Professor Sheila Sherlock at the Royal Free Hospital. Working with Prof. Sherlock, he developed a method to measure serum ferritin and demonstrated its value in estimating liver iron stores and to guide venesection therapy in hemochromatosis. The resulting paper, published in 1975, became the first Gastroenterology paper of Jesus Prieto. Dr. Prieto moved back to Valladolid, in 1977, and he became Professor of Medicine at the University of Santiago de Compostela. Finally, in 1980, he walked the ‘‘Camino the Santiago’’ backward and reached his final destination, the University of Navarra in Pamplona, Spain. He quickly became one of the most influent members of the faculty and the School of Medicine and became Chairman of Medicine. Prof. Prieto is a visionary academic leader! He guided the Hepatology section of the University of Navarra towards international recognition and excellence and then envisioned a research

Oxidative Stress in Nonautoimmune Biliary Diseases

The diseases primarily affecting the biliary epithelium are collectively termed as cholangiopathies. They comprise a wide group of liver pathologies, most often characterized by a chronic progressive and disabling clinical course. Depending upon the nature of the primary insult, cholangiopathies can be categorized as drug-induced, idiopathic, immunomediated, infectious, inherited/genetic, ischemic, and tumoral (Table 13.1). Unfortunately, pathogenetic mechanisms underlying the progression of these diseases are still uncertain.