Virginia Hernández-Gea

Transfusion Strategies for Acute Upper Gastrointestinal Bleeding

BACKGROUND The hemoglobin threshold for transfusion of red cells in patients with acute gastrointestinal bleeding is controversial. We compared the efficacy and safety of a restrictive transfusion strategy with those of a liberal transfusion strategy. METHODS We enrolled 921 patients with severe acute upper gastrointestinal bleeding and randomly assigned 461 of them to a restrictive strategy (transfusion when the hemoglobin level fell below 7 g per deciliter) and 460 to a liberal strategy (transfusion when the hemoglobin fell below 9 g per deciliter). Randomization was stratified according to the presence or absence of liver cirrhosis. RESULTS A total of 225 patients assigned to the restrictive strategy (51%), as compared with 61 assigned to the liberal strategy (14%), did not receive transfusions (P<0.001) [corrected].The probability of survival at 6 weeks was higher in the restrictive-strategy group than in the liberal-strategy group (95% vs. 91%; hazard ratio for death with restrictive strategy, 0.55; 95% confidence interval [CI], 0.33 to 0.92; P=0.02). Further bleeding occurred in 10% of the patients in the restrictive-strategy group as compared with 16% of the patients in the liberal-strategy group (P=0.01), and adverse events occurred in 40% as compared with 48% (P=0.02). The probability of survival was slightly higher with the restrictive strategy than with the liberal strategy in the subgroup of patients who had bleeding associated with a peptic ulcer (hazard ratio, 0.70; 95% CI, 0.26 to 1.25) and was significantly higher in the subgroup of patients with cirrhosis and Child-Pugh class A or B disease (hazard ratio, 0.30; 95% CI, 0.11 to 0.85), but not in those with cirrhosis and Child-Pugh class C disease (hazard ratio, 1.04; 95% CI, 0.45 to 2.37). Within the first 5 days, the portal-pressure gradient increased significantly in patients assigned to the liberal strategy (P=0.03) but not in those assigned to the restrictive strategy. CONCLUSIONS As compared with a liberal transfusion strategy, a restrictive strategy significantly improved outcomes in patients with acute upper gastrointestinal bleeding. (Funded by Fundació Investigació Sant Pau; ClinicalTrials.gov number, NCT00414713.).

Pathogenesis of Liver Fibrosis

Liver fibrosis is a major cause of morbidity and mortality worldwide due to chronic viral hepatitis and, more recently, from fatty liver disease associated with obesity. Hepatic stellate cell activation represents a critical event in fibrosis because these cells become the primary source of extracellular matrix in liver upon injury. Use of cell-culture and animal models has expanded our understanding of the mechanisms underlying stellate cell activation and has shed new light on genetic regulation, the contribution of immune signaling, and the potential reversibility of the disease. As pathways of fibrogenesis are increasingly clarified, the key challenge will be translating new advances into the development of antifibrotic therapies for patients with chronic liver disease.

Hepatocellular Carcinoma: Reasons for Phase III Failure and Novel Perspectives on Trial Design

Hepatocellular carcinoma (HCC) is a major health problem. Most patients with HCC experience a recurrence after resection/ablation or are diagnosed at advanced stages. Sorafenib remains the only approved systemic drug for these patients. Molecular therapies targeting signaling cascades involved in hepatocarcinogenesis have been explored in phase III clinical trials. However, none of the drugs tested have shown positive results in the first-line (brivanib, sunitinib, erlotinib, and linifanib) or second-line (brivanib, everolimus) setting after sorafenib progression. Reasons for failure are heterogeneous and include lack of understanding of critical drivers of tumor progression/dissemination, liver toxicity, flaws in trial design, or marginal antitumoral potency. These trials are also challenging time to progression as a surrogate endpoint of survival. Trials ongoing testing drugs head-to-head versus sorafenib in “all comers” might have difficulties in achieving superior results in the first line. Novel trials are also designed testing drugs in biomarker-based subpopulations of patients with HCC. Most common mutations, however, are undruggable, such as p53 and CTNNB1. Two types of studies are proposed: (i) phase II pivotal proof-of-concept studies testing drugs blocking potential oncogenic addiction loops, such as the one testing MEK inhibitors in RAS+ patients or amplification of FGF19 as a target; and (ii) phase II to III studies using biomarker-based trial enrichment for defining HCC subpopulations, such as the case of enriching for MET-positive tumors. These strategies have been deemed successful in breast, melanoma, and lung cancers, and are expected to change the landscape of trial design of HCC. Clin Cancer Res; 20(8); 2072–9. ©2014 AACR.

Medical therapies for hepatocellular carcinoma: a critical view of the evidence

The management of hepatocellular carcinoma (HCC) has substantially changed in the past few decades. Improvements in patient stratification (for example, using the Barcelona Clinic Liver Cancer staging system) and the introduction of novel therapies (such as sorafenib) have improved patient survival. Nevertheless, HCC remains the third most common cause of cancer-related deaths worldwide. Decision-making largely relies on evidence-based criteria, as depicted in the US and European clinical practice guidelines, which endorse five therapeutic recommendations: resection; transplantation; radiofrequency ablation; chemoembolization; and sorafenib. However, areas still exist in which uncertainty precludes a strong recommendation, such as the role of adjuvant therapies after resection, radioembolization with yttrium-90 or second-line therapies for advanced HCC. Many clinical trials that are currently ongoing aim to answer these questions. The first reported studies, however, failed to identify novel therapeutic alternatives (that is, sunitinib, erlotinib or brivanib). Moreover, genomic profiling has enabled patient classification on the basis of molecular parameters, and has facilitated the development of new effective drugs. However, no oncogene addiction loops have been identified so far, as has been the case with other cancers such as melanoma, lung or breast cancer. Efforts that focus on the implementation of personalized medicine approaches in HCC will probably dominate research in the next decade.

Endoplasmic reticulum stress induces fibrogenic activity in hepatic stellate cells through autophagy

BACKGROUND & AIMS Metabolic stress during liver injury enhances autophagy and provokes stellate cell activation, with secretion of scar matrix. Conditions that augment protein synthesis increase demands on the endoplasmic reticulum (ER) folding capacity and trigger the unfolded protein response (UPR) to cope with resulting ER stress. Generation of reactive oxygen species (ROS) is a common feature of hepatic fibrogenesis, and crosstalk between oxidant stress and ER stress has been proposed. The aim of our study was to determine the impact of oxidant and ER stress on stellate cell activation. METHODS Oxidant stress was induced in hepatic stellate cells using H2O2 in culture or by ethanol feeding in vivo, and the UPR was analyzed. Because the branch of the UPR mainly affected was IREα, we blocked this pathway in stellate cells and analyzed the fibrogenic response, together with autophagy and downstream MAPK signaling. The Nrf2 antioxidant response was also evaluated in stellate cells under oxidant stress conditions. RESULTS H2O2 treatment in culture or ethanol feeding in vivo increased the UPR based on splicing of XBP1 mRNA, which triggered autophagy. The Nrf2-mediated antioxidant response, as measured by qRT-PCR of its target genes was also induced under ER stress conditions. Conversely, blockade of the IRE1α pathway in stellate cells significantly decreased both their activation and autophagic activity in a p38 MAPK-dependent manner, leading to a reduced fibrogenic response. CONCLUSIONS These data implicate mechanisms underlying protein folding quality control in regulating the fibrogenic response in hepatic stellate cells.

DNA methylation-based prognosis and epidrivers in hepatocellular carcinoma

Epigenetic deregulation has emerged as a driver in human malignancies. There is no clear understanding of the epigenetic alterations in hepatocellular carcinoma (HCC) and of the potential role of DNA methylation markers as prognostic biomarkers. Analysis of tumor tissue from 304 patients with HCC treated with surgical resection allowed us to generate a methylation‐based prognostic signature using a training‐validation scheme. Methylome profiling was done with the Illumina HumanMethylation450 array (Illumina, Inc., San Diego, CA), which covers 96% of known cytosine‐phosphate‐guanine (CpG) islands and 485,000 CpG, and transcriptome profiling was performed with Affymetrix Human Genome U219 Plate (Affymetrix, Inc., Santa Clara, CA) and miRNA Chip 2.0. Random survival forests enabled us to generate a methylation signature based on 36 methylation probes. We computed a risk score of mortality for each individual that accurately discriminated patient survival both in the training (221 patients; 47% hepatitis C–related HCC) and validation sets (n = 83; 47% alcohol‐related HCC). This signature correlated with known predictors of poor outcome and retained independent prognostic capacity of survival along with multinodularity and platelet count. The subset of patients identified by this signature was enriched in the molecular subclass of proliferation with progenitor cell features. The study confirmed a high prevalence of genes known to be deregulated by aberrant methylation in HCC (e.g., Ras association [RalGDS/AF‐6] domain family member 1, insulin‐like growth factor 2, and adenomatous polyposis coli) and other solid tumors (e.g., NOTCH3) and describes potential candidate epidrivers (e.g., septin 9 and ephrin B2). Conclusions: A validated signature of 36 DNA methylation markers accurately predicts poor survival in patients with HCC. Patients with this methylation profile harbor messenger RNA–based signatures indicating tumors with progenitor cell features. (Hepatology 2015;61:1945–1956)

Idiopathic portal hypertension: Natural history and long-term outcome

Idiopathic portal hypertension (IPH) is a rare cause of intrahepatic portal hypertension. Data on natural history and prognosis of IPH are limited. We sought to describe the complications and long‐tem outcome of IPH by retrospectively studying 69 biopsy‐proven cases of IPH. Mean duration of follow‐up was 6.7 ± 4.6 years. All patients had evidence of portal hypertension (PH) at diagnosis, and 42% were symptomatic. Variceal bleeding (VB) was the most common manifestation. In those without bleeding at diagnosis, 74% had varices at first endoscopy. In those with large varices, the 1‐year probability of first bleeding despite primary prophylaxis was 9%. The 1‐year probability of rebleeding was 22%. Ascites and hepatic encephalopathy was documented in 26% and 7% of patients, respectively, at least once during the clinical course. The 1‐year probability of developing portal vein thrombosis (PVT) was 9%, and 53% of patients receiving anticoagulation achieved recanalization. Human immunodeficiency virus (HIV) infection and VB at diagnosis were the independent predictors of PVT. Seven patients died (6 as a result of an IPH‐related cause) and 2 were transplanted. Probability of liver transplantation–free survival was 82% at 10 years. Presence of a severe associated disorder and ascites as a presenting symptom were associated with poor survival. Conclusion: Variceal bleeding is a major complication of IPH. Using, in IPH patients, the same management approach for PH as in cirrhosis is safe and maintains a low incidence of first bleeding and rebleeding in IPH patients. PVT is a frequent complication, particularly in those with HIV infection. Despite several complications, overall survival of patients with IPH is considerably good. (Hepatology 2014;59:2276–2285)

Role of calreticulin mutations in the aetiological diagnosis of splanchnic vein thrombosis

BACKGROUND & AIMS Myeloproliferative neoplasms are the most common aetiological cause of splanchnic vein thrombosis (SVT). In these patients, the JAK2V617F mutation has facilitated the diagnosis of an underlying myeloproliferative neoplasm (MPN). Recently, somatic mutations of the calreticulin (CALR) gene have been identified in MPN patients lacking the JAK2 mutation. The aim of the present study was to ascertain whether CALR mutations could also play a role in the diagnosis of masked MPN in SVT. METHODS We included 209 patients with SVT (140 with PVT and 69 with Budd-Chiari syndrome) who had a complete aetiological diagnostic work-out. They were investigated for CALR mutations. RESULTS CALR mutations were found in 4 of the 209 patients (1.9%). They represented 5.4% of patients with an underlying MPN of whom all had already been diagnosed with a MPN using conventional criteria including bone marrow biopsy findings. CONCLUSIONS In the screening of underlying MPNs in patients with SVT, given its high frequency in these disorders, the JAK2 mutation must be evaluated first and, if negative, CALR mutations should also be investigated. This approach would increase the diagnostic yield of masked MPNs by reducing the need for additional studies.

Autophagy fuels tissue fibrogenesis

Activation of hepatic stellate cells (HSC), a resident pericytic cell in liver, into a proliferative and fibrogenic cell type, is the principal event underlying hepatic fibrosis following injury. Release of lipid droplets (LD) containing retinyl esters and triglyceride is a defining feature of HSC activation, yet the basis for this release has remained mysterious. Here we offer a surprising discovery that autophagy is the missing link underlying LD release, by stimulating metabolism of their contents to provide the energy vital to fuel HSC activation. By specifically inhibiting the autophagic pathway in activated HSC, LD release is impaired and cellular ATP levels are decreased. Moreover, animals with HSC-specific deletion of Atg7 display attenuated activation following liver injury, leading to reduced fibrosis in vivo. We further demonstrate that fibrogenic cells from other organs, including kidney and lung, also rely on autophagy as a core pathway driving the scarring response. Our results provide a novel framework for understanding pathways underlying fibrogenic cell responses to tissue injury.

Drugs plus ligation to prevent rebleeding in cirrhosis: an updated systematic review.

Combined therapy with endoscopic variceal ligation (EVL) and β‐blockers ± isosorbide mononitrate (ISMN) is currently recommended to prevent variceal rebleeding. However, the role of this combined therapy has been challenged by some studies. We performed a systematic review to assess the value of combined therapy with EVL and β‐blockers ± ISMN as compared with each treatment alone to prevent rebleeding.