In the present study, we studied chronic HCV patients who responded to IFN-based therapy as evidenced by absence of HCV RNA at the end of treatment, and focused on two issues that have not received much attention. Firstly, we evaluated whether specific genes or gene expression patterns in blood were able to distinguish responder patients with a viral relapse from responder patients who remained virus-negative after cessation of treatment. We found that chronic HCV patients who were sustained responders and relapsers to IFN-based therapy showed comparable baseline clinical parameters and immune composition in blood. However, at baseline, the gene expression profiles of a set of 18 genes predicted treatment outcome with an accuracy of 94%. Secondly, we examined whether patients with successful therapy-induced clearance of HCV still exhibited gene expression patterns characteristic for HCV, or whether normalization of their transcriptome was observed. We observed that the relatively high expression of IFN-stimulated genes (ISG) in chronic HCV patients prior to therapy was reduced after successful IFN-based antiviral therapy (at 24 weeks follow-up). These ISG included CXCL10, OAS1, IFI6, DDX60, TRIM5 and STAT1. In addition, 1428 differentially expressed non-ISG genes were identified in paired pre- and post-treatment samples from sustained responders, which included genes involved in TGF- signaling, apoptosis, autophagy, and nucleic acid and protein metabolism. Interestingly, 1424 genes were identified with altered expression in responder patients after viral eradication in comparison to normal expression levels in healthy individuals. Additionally, aberrant expression of a subset of these genes, including IL-32, IL-16, CCND3 and RASSF1, was also observed at baseline. Our findings indicate that successful antiviral therapy of chronic HCV patients does not lead to normalization of their blood transcriptional signature. The altered transcriptional activity may reflect HCV-induced liver damage in previously infected individuals.
Gene expression profiling to predict and assess the consequences of therapy-induced virus eradication in chronic hepatitis C virus infection.
Sex, Specimen part, Disease, Race
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Drug-induced endoplasmic reticulum and oxidative stress responses independently sensitize toward TNFα-mediated hepatotoxicity.
Sex, Age, Specimen part, Cell line, Treatment, Subject
View SamplesDrug-induced liver injury (DILI) is an important clinical problem. Here we used a genomics approach to establish the critical drug-induced toxicity pathways that act in synergy with the pro-inflammatory cytokine tumor necrosis factor (TNF) to cause cell death of liver HepG2 cells. Transcriptomics of the cell injury stress response pathways initiated by two hepatoxicants, diclofenac and carbamazepine, revealed the endoplasmic reticulum (ER) stress/translational initiation signaling and Nrf2 antioxidant signaling as two major affected pathways, which was similar to that observed for the majority of ~80 DILI compounds in primary human hepatocytes. The ER stress was primarily related to PERK and ATF4 activation and subsequent expression of CHOP, which was all independent of TNF signaling. Identical ATF4 dependent transcriptional programs were observed in primary human hepatocytes as well as primary precision cut human liver slices. Targeted RNA interference studies revealed that while ER stress signaling through IRE1 and ATF6 acted cytoprotective, activation of the ER stress protein kinase PERK and subsequent expression of CHOP was pivotal for the onset of drug/TNF-induced apoptosis. While inhibition of the Nrf2-dependent adaptive oxidative stress response enhanced the drug/TNF cytotoxicity, Nrf2 signaling did not affect CHOP expression. Both hepatotoxic drugs enhanced expression of the translational initiation factor EIF4A1, which was essential for CHOP expression and drug/TNF-mediated cell killing. Our data support a model in which enhanced drug-induced translation initiates PERK-mediated CHOP signaling in an EIF4A1 dependent manner, thereby sensitizing towards caspase-8-dependent TNF induced apoptosis.
Drug-induced endoplasmic reticulum and oxidative stress responses independently sensitize toward TNFα-mediated hepatotoxicity.
Cell line, Treatment
View SamplesDrug-induced liver injury (DILI) is an important clinical problem. Here we used a genomics approach to establish the critical drug-induced toxicity pathways that act in synergy with the pro-inflammatory cytokine tumor necrosis factor (TNF) to cause cell death of liver HepG2 cells. Transcriptomics of the cell injury stress response pathways initiated by two hepatoxicants, diclofenac and carbamazepine, revealed the endoplasmic reticulum (ER) stress/translational initiation signaling and Nrf2 antioxidant signaling as two major affected pathways, which was similar to that observed for the majority of ~80 DILI compounds in primary human hepatocytes. The ER stress was primarily related to PERK and ATF4 activation and subsequent expression of CHOP, which was all independent of TNF signaling. Identical ATF4 dependent transcriptional programs were observed in primary human hepatocytes as well as primary precision cut human liver slices. Targeted RNA interference studies revealed that while ER stress signaling through IRE1 and ATF6 acted cytoprotective, activation of the ER stress protein kinase PERK and subsequent expression of CHOP was pivotal for the onset of drug/TNF-induced apoptosis. While inhibition of the Nrf2-dependent adaptive oxidative stress response enhanced the drug/TNF cytotoxicity, Nrf2 signaling did not affect CHOP expression. Both hepatotoxic drugs enhanced expression of the translational initiation factor EIF4A1, which was essential for CHOP expression and drug/TNF-mediated cell killing. Our data support a model in which enhanced drug-induced translation initiates PERK-mediated CHOP signaling in an EIF4A1 dependent manner, thereby sensitizing towards caspase-8-dependent TNF induced apoptosis.
Drug-induced endoplasmic reticulum and oxidative stress responses independently sensitize toward TNFα-mediated hepatotoxicity.
Sex, Age, Specimen part, Treatment
View SamplesDrug-induced liver injury (DILI) is an important clinical problem. Here we used a genomics approach to establish the critical drug-induced toxicity pathways that act in synergy with the pro-inflammatory cytokine tumor necrosis factor (TNF) to cause cell death of liver HepG2 cells. Transcriptomics of the cell injury stress response pathways initiated by two hepatoxicants, diclofenac and carbamazepine, revealed the endoplasmic reticulum (ER) stress/translational initiation signaling and Nrf2 antioxidant signaling as two major affected pathways, which was similar to that observed for the majority of ~80 DILI compounds in primary human hepatocytes. The ER stress was primarily related to PERK and ATF4 activation and subsequent expression of CHOP, which was all independent of TNF signaling. Identical ATF4 dependent transcriptional programs were observed in primary human hepatocytes as well as primary precision cut human liver slices. Targeted RNA interference studies revealed that while ER stress signaling through IRE1 and ATF6 acted cytoprotective, activation of the ER stress protein kinase PERK and subsequent expression of CHOP was pivotal for the onset of drug/TNF-induced apoptosis. While inhibition of the Nrf2-dependent adaptive oxidative stress response enhanced the drug/TNF cytotoxicity, Nrf2 signaling did not affect CHOP expression. Both hepatotoxic drugs enhanced expression of the translational initiation factor EIF4A1, which was essential for CHOP expression and drug/TNF-mediated cell killing. Our data support a model in which enhanced drug-induced translation initiates PERK-mediated CHOP signaling in an EIF4A1 dependent manner, thereby sensitizing towards caspase-8-dependent TNF induced apoptosis.
Drug-induced endoplasmic reticulum and oxidative stress responses independently sensitize toward TNFα-mediated hepatotoxicity.
Specimen part, Treatment, Subject
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Drug-induced histone eviction from open chromatin contributes to the chemotherapeutic effects of doxorubicin.
Age, Specimen part, Cell line, Treatment, Time
View SamplesOne major class of anti-cancer drugs targets topoisomerase II to induce DNA double-strand breaks and cell death of fast growing cells. In vitro experiments showed that doxorubicin can induce histone eviction as well as DNA damage, while etoposide can only induce DNA damage. Here, we compare the transcription responses of different tissues to doxorubicin or etoposide treatment in vivo.
Drug-induced histone eviction from open chromatin contributes to the chemotherapeutic effects of doxorubicin.
Age, Specimen part, Treatment, Time
View SamplesMice lacking the zinc finger transcription factor Specificity protein 3 (Sp3) die prenatally in the C57Bl/6 background. To elucidate the cause of mortality we analyzed the potential role of Sp3 in embryonic heart development. Sp3 null hearts display defective looping at E10.5, and at E14.5 the Sp3 null mutants have developed a range of severe cardiac malformations. In an attempt to position Sp3 in the cardiac developmental hierarchy, we analysed the expression patterns of >15 marker genes in Sp3 null hearts. Expression of Cardiac ankyrin repeat protein (Carp) was downregulated prematurely after E12.5, while expression of the other marker genes was not affected. ChIP analysis revealed that Sp3 is bound to the Carp promoter region in vivo. Microarray analysis indicates that small molecule metabolism and cell-cell interactions are the most significantly affected biological processes in E12.5 Sp3 null myocardium. Since the epicardium showed distension from the myocardium, we studied expression of Wt1, a marker for epicardial cells. Wt1 expression was diminished in epicardium-derived cells in the myocardium of Sp3 null hearts. We conclude that Sp3 is required for normal cardiac development, and suggest that it has a crucial role in myocardial differentiation. (
Transcription factor Sp3 knockout mice display serious cardiac malformations.
No sample metadata fields
View SamplesDifferential mRNA expression patterns were seen in GSC272-vector compared to GSC272-POSTN shRNA tumors.
Periostin (POSTN) Regulates Tumor Resistance to Antiangiogenic Therapy in Glioma Models.
Specimen part, Treatment
View SamplesBevacizumab induces glioblastoma resistance in two in vivo xenograft models. Two cell lines were developed with acquired resistance to bevacizumab. Gene expression difference were analyzed between treated and untreated tumors.
Acquired resistance to anti-VEGF therapy in glioblastoma is associated with a mesenchymal transition.
Specimen part, Treatment
View Samples