Purpose: The goal of this study was to determine biological consequences during liver regeneration following partial hepatectomy in mice by next-generation sequencing. A particular interest was to compare mice with either a floxed b-PDGFR allele to mice that harbored a deletion of b-PDGFR in hepatic stellate cells (HSCs), by crossing b-PDGFR fl/fl mice with transgenic GFAP-Cre mice. Methods: b-PDGFR fl/fl mice or mice with a HSC-specific deletion of b-PDGFR underwent either sham operation or 70% partial hepatectomy. Following 72 hours, livers were collected and total RNA was extracted using tizol, followed by a purification using Quiagen spin columns including an on-column DNAse digestion step. Conclusion: Our study represents a detailed analysis of hepatic transcriptome, with biologic replicates, generated by RNA-seq technology of livers following sham operation or partial hepatectomy in b-PDGFR fl/fl mice or b-PDGFRfl/fl/GRAP-Cre mice. Overall design: Whole liver mRNA profiles of sham operated livers or livers collected 72hours after partial hepatectomy of beta-PDGFR fl/fl and beta-PDGFR fl/fl/GFAP-Cre (creating a hepatic stellate cell-specific deletion of b-PDGFR) mice were generated by deep sequencing, in duplicate, using Illumina HiSeq2000.
Induction and contribution of beta platelet-derived growth factor signalling by hepatic stellate cells to liver regeneration after partial hepatectomy in mice.
No sample metadata fields
View SamplesUHRF1 (Ubiquitin-like, containing PHD and RING finger domains, 1) recruits DNMT1 to hemimethylated DNA during replication, is essential for maintaining DNA methylation patterns during cell division and is suggested to direct additional repressive epigenetic marks. Uhrf1 mutation in zebrafish results in multiple embryonic defects including failed hepatic outgrowth, but the epigenetic basis of these phenotypes is not known. We find that DNA methylation is the only epigenetic mark that is depleted in uhrf1 mutants and make the surprising finding that despite the reduced organ size in uhrf1 mutants, genes regulating DNA replication and S-phase progression were highly upregulated. Further, there is a striking increase in BrdU incorporation in uhrf1 mutant cells, and they retained BrdU labeling over several days, indicating they are arrested in S-phase. Moreover, some of the label retaining nuclei co-localized with TUNEL positive nuclei, suggesting that arrested cells are responsible for apoptosis. Importantly, dnmt1 mutation phenocopies the S-phase arrest and hepatic outgrowth defects in uhrf1 mutants and Dnmt1 knock-down enhances the uhrf1 hepatic phenotype. Together, these data indicate that DNA hypomethylation is sufficient to generate the uhrf1 mutant phenotype by promoting an S-phase arrest. We thus propose that cell cycle arrest is a mechanism to restrict propagation of epigenetically deranged cells during embryogenesis.
DNA hypomethylation induces a DNA replication-associated cell cycle arrest to block hepatic outgrowth in uhrf1 mutant zebrafish embryos.
No sample metadata fields
View SamplesMetastasis is the deadliest phase of cancer progression. Experimental models using immunodeficient mice have been used to gain insights into the mechanisms of metastasis. We report here the identification of a metastasis aggressiveness gene expression signature derived using human melanoma cells selected based on their metastatic potentials in a xenotransplant metastasis model. Comparison with expression data from human melanoma patients shows that this metastasis gene signature correlates with the aggressiveness of melanoma metastases in human patients. Many genes encoding secreted and membrane proteins are included in the signature, suggesting the importance of tumor-microenvironment interactions during metastasis.
Gene expression changes in an animal melanoma model correlate with aggressiveness of human melanoma metastases.
No sample metadata fields
View SamplesMetastasis is the deadliest phase of cancer progression. Experimental models using immunodeficient mice have been used to gain insights into the mechanisms of metastasis. We report here the identification of a metastasis aggressiveness gene expression signature derived using human melanoma cells selected based on their metastatic potentials in a xenotransplant metastasis model. Comparison with expression data from human melanoma patients shows that this metastasis gene signature correlates with the aggressiveness of melanoma metastases in human patients. Many genes encoding secreted and membrane proteins are included in the signature, suggesting the importance of tumor-microenvironment interactions during metastasis.
Gene expression changes in an animal melanoma model correlate with aggressiveness of human melanoma metastases.
No sample metadata fields
View SamplesMetastasis is the deadliest phase of cancer progression. Experimental models using immunodeficient mice have been used to gain insights into the mechanisms of metastasis. We report here the identification of a metastasis aggressiveness gene expression signature derived using human melanoma cells selected based on their metastatic potentials in a xenotransplant metastasis model. Comparison with expression data from human melanoma patients shows that this metastasis gene signature correlates with the aggressiveness of melanoma metastases in human patients. Many genes encoding secreted and membrane proteins are included in the signature, suggesting the importance of tumor-microenvironment interactions during metastasis.
Gene expression changes in an animal melanoma model correlate with aggressiveness of human melanoma metastases.
No sample metadata fields
View SamplesNotch intracellular domain (NICD) is the active form of the Notch receptor. In this mouse model, NICD is inserted in the Rosa26 locus downstream of a loxP-STOP-LoxP (lsl) sequence and therefore NICD expression is dependant on Cre recombinase expression. These mice are crossed with the AFP-Cre strain that expresses Cre in hepatoblasts due to its regulation by the AFP promoter and albumin enhancer. Mice from 6 to 12 months are sacrificed and liver RNA samples from control monotransgenic Rosa26-lsl-NICD and confirmed HCC lesions from bitransgenic AFP-Cre/Rosa26-lsl-NICD (AFP-NICD) are obtained. Exon expression profiling of these samples are submitted.
Notch signaling is activated in human hepatocellular carcinoma and induces tumor formation in mice.
Age, Specimen part
View SamplesLiver samples of mice harboring liver-specific deletion of Lats2 (Lats2-CKO) were compared to WT mice.
The LATS2 tumor suppressor inhibits SREBP and suppresses hepatic cholesterol accumulation.
Sex, Age, Specimen part
View SamplesThe goal of this study is to compare gene expression levels in uhrf1 mutants with global DNA hypomethylation to WT siblings Overall design: 10 whole embryos were pooled per sample of either 5 dpf old uhrf1 mutants or phenotypically WT siblings and RNA was extracted. Libraries were prepared according to Illumina Truseq RNA sample prep kit, version 2, followed by Ribo-Zero Gold treatment
Loss of DNA methylation in zebrafish embryos activates retrotransposons to trigger antiviral signaling.
No sample metadata fields
View SamplesHepatocellular carcinoma (HCC) is a highly heterogeneous disease, and prior attempts to develop genomic-based classification for HCC have yielded highly divergent results, indicating difficulty in identifying unified molecular anatomy. We performed a meta-analysis of gene expression profiles in data sets from eight independent patient cohorts across the world. In addition, aiming to establish the real world applicability of a classification system, we profiled 118 formalin-fixed, paraffin-embedded tissues from an additional patient cohort. A total of 603 patients were analyzed, representing the major etiologies of HCC (hepatitis B and C) collected from Western and Eastern countries. We observed three robust HCC subclasses (termed S1, S2, and S3), each correlated with clinical parameters such as tumor size, extent of cellular differentiation, and serum alpha-fetoprotein levels. An analysis of the components of the signatures indicated that S1 reflected aberrant activation of the WNT signaling pathway, S2 was characterized by proliferation as well as MYC and AKT activation, and S3 was associated with hepatocyte differentiation. Functional studies indicated that the WNT pathway activation signature characteristic of S1 tumors was not simply the result of beta-catenin mutation but rather was the result of transforming growth factor-beta activation, thus representing a new mechanism of WNT pathway activation in HCC. These experiments establish the first consensus classification framework for HCC based on gene expression profiles and highlight the power of integrating multiple data sets to define a robust molecular taxonomy of the disease.
Integrative transcriptome analysis reveals common molecular subclasses of human hepatocellular carcinoma.
No sample metadata fields
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Molecular Liver Cancer Prevention in Cirrhosis by Organ Transcriptome Analysis and Lysophosphatidic Acid Pathway Inhibition.
Sex, Specimen part, Disease, Treatment
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