Focal nodular hyperplasias (FNHs) are benign liver lesions considered to be a hyperplastic response to increased blood flow in otherwise normal liver. In contrast, FNH-like nodules occur in cirrhotic liver but share similar histopathological features. To better understand the pathophysiology of FNH, we performed a transcriptomic analysis. Methods: Affymetrix and cDNA microarrays were used to compare gene expression in eight FNHs with that in tissue from six normal livers. Selected genes were validated with quantitative RT-PCR in 70 benign liver tumors including adenomas and cirrhotic and FNH-like lesions. Results: Among the deregulated genes in FNHs, 19 were physiologically zonated in the normal liver lobule. All six periveinous genes were up-regulated in FNH, whereas 13 genes normally expressed in the periportal area were down-regulated. Immunohistochemistry revealed that glutamine synthetase was markedly overexpressed, forming anastomosed areas usually centered on visible veins. -catenin mRNA was slightly but significantly overexpressed, as were several known -catenin target genes. Moreover, activated hypophosphorylated -catenin protein accumulated in FNH in the absence of activating mutations. These results suggest zonated activation of the -catenin pathway specifically in FNH, whereas the other benign hepatocellular tumors, including FNH-like lesions, demonstrated an entirely different pattern of -catenin expression. Conclusions: In FNH, increased expression of the -catenin pathway was restricted to enlarged periveinous areas, which may explain the slight polyclonal over-proliferation of hepatocytes at the origin of the lesion. FNH-like nodules may have a different pathogenetic origin.
The beta-catenin pathway is activated in focal nodular hyperplasia but not in cirrhotic FNH-like nodules.
Sex, Specimen part, Disease
View SamplesInflammatory hepatocellular adenomas (IHCA) are benign liver tumours defined by the presence of inflammatory infiltrates and by the elevated expression of inflammatory proteins in tumour hepatocytes1,2. Here we show a striking activation of the IL6 signalling pathway in this tumour type, and sequencing candidate genes pinpointed this response to somatic gain-of-function mutations in the IL6ST gene that encodes the signalling co-receptor gp130. Indeed, ~70% of IHCA harbour small in-frame deletions that target the binding site of gp130 for IL6, and expression of the most frequent gp130 mutant, Delta-STVY190, in hepatocellular cells activates STAT3 in absence of ligand. Further, analysis of hepatocellular carcinomas revealed rare gp130 alterations always accompanied by -catenin-activating mutations, suggesting a cooperative effect of these signalling pathways in the malignant conversion of hepatocytes. The recurrent gain-of-function gp130 mutations in these human hepatocellular adenomas explains their inflammatory phenotype, and suggest that similar alterations may occur in other inflammatory epithelial tumours with STAT3 activation.
Frequent in-frame somatic deletions activate gp130 in inflammatory hepatocellular tumours.
Sex, Specimen part, Disease
View SamplesTo identify the activity-induced gene expression programs in inhibitory and excitatory neurons, we analyzed RNA extracted from cultured E14 mouse MGE- and CTX-derived neurons (DIV 10) after these cultures were membrane-depolarized for 0, 1 and 6 hrs with 55mM extracellular KCl. To identify the gene programs regulated in these cells by the activity-induced early-response transcription factor Npas4, we repeated the same experiment in the MGE- and CTX-cultures lacking Npas4 (Npas4-KO).
Npas4 regulates excitatory-inhibitory balance within neural circuits through cell-type-specific gene programs.
Specimen part, Treatment, Time
View SamplesAlthough the induction of C-FOS in the brain has been extensively studied for several decades to date there has been no attempt to identify the targets of C-FOS at a genome wide level, and it was not known how many genes C-FOS activates in a given cell. To identify potential C-FOS target genes, we performed microarray analysis on RNA obtained from mouse cortical (mCTX) neurons infected with lentivirus containing either a control shRNA (targeting firefly luciferase) or c-Fos shRNA that were subsequently depolarized with 0, 1, 3, or 6 hours of KCl.
Genome-wide identification and characterization of functional neuronal activity-dependent enhancers.
Specimen part
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Integrative genomic analysis of the human immune response to influenza vaccination.
Sex, Specimen part, Treatment, Subject, Time
View SamplesThe purpose of the study was to assess the patterns of global gene expression in peripheral blood cells before and at three time points after the administration of a trivalent influenza vaccine in human male subjects, and to relate these to the antibody response to the vaccine. The antibody titer data for these subjects is provided as a supplemental file.
Integrative genomic analysis of the human immune response to influenza vaccination.
Sex, Specimen part, Treatment, Subject, Time
View SamplesThe purpose of the study was to assess the patterns of global gene expression in peripheral blood cells before and at three time points after the administration of a trivalent influenza vaccine in human female subjects, and to relate these to the antibody response to the vaccine
Integrative genomic analysis of the human immune response to influenza vaccination.
Sex, Specimen part, Treatment, Subject, Time
View SamplesHepatocellular carcinoma (HCC) is ranked second in cancer-associated deaths worldwide. Most cases of HCC are secondary to either a viral hepatitis infection (hepatitis B or C) or cirrhosis (alcoholism being the most common cause of hepatic cirrhosis). It is a complex and heterogeneous tumor due to activation of multiple cellular pathways and molecular alterations.
Exome sequencing of hepatocellular carcinomas identifies new mutational signatures and potential therapeutic targets.
Sex, Age, Specimen part, Disease, Disease stage
View SamplesTo further investigate the underlying mechanisms of severe acute respiratory syndrome (SARS) pathogenesis and evaluate the therapeutic efficacy of potential drugs and vaccines it is necessary to use an animal model that is highly representative of the human condition in terms of respiratory anatomy, physiology and clinical sequelae. The ferret, Mustela putorius furo, supports SARS-CoV replication and displays many of the symptoms and pathological features seen in SARS-CoV-infected humans. We have recently established a SARS-CoV infection-challenge ferret platform for use in evaluating potential therapeutics to treat SARS. The main objective of the current study was to extend our previous results and identify early host immune responses upon infection and determine immune correlates of protection upon challenge with SARS-CoV in ferrets.
Lack of innate interferon responses during SARS coronavirus infection in a vaccination and reinfection ferret model.
Specimen part
View SamplesMetastasis is the leading cause of death for cancer patients. Consequently it is imperative that we improve our understanding of the molecular mechanisms that underlie progression of tumour growth towards malignancy. Advances in genome characterisation technologies have been very successful in identifying commonly mutated or misregulated genes in a variety of human cancers. However the difficulty in evaluating whether these candidate genes drive tumour progression remains a major challenge. Using the genetic amenability of Drosophila melanogaster we generated tumours with specific genotypes in the living animal and carried out a detailed systematic loss-of-function analysis to identify conserved genes that enhance or suppress epithelial tumour progression. This enabled the discovery of functional cooperative regulators of invasion and the establishment of a network of conserved invasion suppressors. This includes constituents of the cohesin complex, which can either promote individual or collective invasion, depending on the severity of effect on cohesin function.
A Genetic Analysis of Tumor Progression in Drosophila Identifies the Cohesin Complex as a Suppressor of Individual and Collective Cell Invasion.
Cell line
View Samples