Patients who cleared HCV viremia early during therapy tended to show favorable outcomes, whereas patients who needed a longer period to clear HCV had poorer outcomes. We explored the mechanisms of treatment resistance by comparing hepatic gene expression before and during treatment
Differential interferon signaling in liver lobule and portal area cells under treatment for chronic hepatitis C.
Specimen part, Time
View SamplesIL28B genotype was shown to be associated with treatment outcome of antiviral thearpy for HCV infection. We tried to clarify the molecular feature that was asocciated with IL2B genotype by comparing Hepatic gene expression of HCV related Hepatocellular carcinoma and non-cancerous tissue with Il28B rs8099917 TT genotype and TG/GG genotype.
Association of interleukin-28B genotype and hepatocellular carcinoma recurrence in patients with chronic hepatitis C.
Specimen part
View SamplesThere is a gradient of -catenin expression along the colonic crypt axis with the highest levels at the crypt bottom. However, it remains unclear whether different levels of canonical Wnt signaling exert distinct roles in the colonic epithelium. In the present study, we first showed that the canonical Wnt signaling is active in the proliferative compartment of normal colonic crypts by separating actively proliferating progenitor cells from non-proliferating cells in the colon using transgenic mice expressing a histone H2B-green fluorescent protein (GFP) fusion protein under the control of a tetracycline responsive regulatory element. Subsequently, we investigated the dose-dependent effect of canonical Wnt activation on colonic epithelial differentiation by controlling the expression levels of stabilized -catenin using a doxycycline-inducible transgenic system in mice. We show that elevated levels of Wnt signaling induce the amplification of Lgr5+ cells, which is accompanied by crypt fission and a reduction in cell proliferation among progenitor cells. In contrast, lower levels of -catenin induction enhanced cell proliferation rates of epithelial progenitors without affecting crypt fission rates. Notably, slow-cycling cells produced by -catenin activation exhibit activation of Notch signaling and the treatment of -catenin expressing mice with a Notch inhibitor turned such slow-cycling cells into actively proliferating cells. Our results indicate that the activation of the canonical Wnt signaling pathway is sufficient for de novo crypt formation, and suggest that different levels of canonical Wnt activations, in cooperation with Notch signaling, establish a hierarchy of slower-cycling stem cells and faster-cycling progenitor cells characteristic for the colonic epithelium.
Dose-dependent roles for canonical Wnt signalling in de novo crypt formation and cell cycle properties of the colonic epithelium.
Sex, Specimen part
View SamplesThe liver may regulate glucose homeostasis by modulating the sensitivity/resistance of peripheral tissues to insulin, by way of the production of secreted proteins, termed hepatokines.
A liver-derived secretory protein, selenoprotein P, causes insulin resistance.
Sex, Specimen part, Disease
View SamplesAberrant DNA methylation is induced at specific promoter CpG islands (CGIs) in contrast with mutations. The specificity is influenced by genome architecture and epigenetic factors, but their relationship is still unknown. In this study, we isolated promoter CGIs susceptible and resistant to aberrant methylation induction during prostate and breast carcinogenesis. The effect of genome architecture was more evident for promoter CGIs susceptible in both of the two tissues than for promoter CGIs susceptible only in one tissue. Multivariate analysis of promoter CGIs with tissue-nonspecific susceptibility showed that genome architecture, namely a remote location from SINE (OR=5.98; 95% CI=2.33-15.34) and from LINE (OR=2.08; 95% CI=1.03-4.21), was associated with increased susceptibility, independent of epigenetic factors such as the presence of RNA polymerase II (OR=0.09; 95% CI=0.02-0.48) and H3K27me3 (OR=3.28; 95% CI=1.17-9.21). These results showed that methylation susceptibility of promoter CGIs is determined both by genome architecture and epigenetic factors, independently.
Effects of genome architecture and epigenetic factors on susceptibility of promoter CpG islands to aberrant DNA methylation induction.
Cell line
View SamplesThe rate of cell differentiation is tightly controlled and critical for normal development and stem cell differentiation. However, so far it has been difficult to control the rate of ESCs differentiation. Here we report the acceleration of the differentiation rate due to the activation of protein kinase A (PKA) and the associated early loss of embryonic stem cells (ESCs) pluripotency markers and the early appearance of mesodermal and other germ layer cell markers.
Protein kinase A accelerates the rate of early stage differentiation of pluripotent stem cells.
Time
View SamplesInstructive mechanisms are present for induction of DNA methylation, as shown by methylation of specific CpG islands (CGIs) by specific inducers and in specific cancers. However, instructive factors involved are poorly understood, except for involvement of low transcription and trimethylation of histone H3 lysine 27 (H3K27me3). Here, we used methylated DNA immunoprecipitation (MeDIP) combined with a CGI oligonucleotide microarray analysis, and identified 5510 and 521 genes with promoter CGIs resistant and susceptible, respectively, to DNA methylation in prostate cancer cell lines. Expression analysis revealed that the susceptible genes had low transcription in a normal prostatic epithelial cell line. Chromatin immunoprecipitation with microarray hybridization (CHiP-chip) analysis of RNA polymerase II (Pol II) and histone modifications showed that, even among the genes with low transcription, the presence of Pol II was associated with marked resistance to DNA methylation (OR = 0.22; 95% CI = 0.12-0.38), and H3K27me3 was associated with increased susceptibility (OR = 11.20; 95% CI = 7.14-17.55). The same was true in normal human mammary epithelial cells for 5430 and 733 genes resistant and susceptible, respectively, to DNA methylation in breast cancer cell lines. These results showed that the presence of Pol II, active or stalled, and H3K27me3 can predict the epigenetic fate of promoter CGIs independently of transcription levels.
The presence of RNA polymerase II, active or stalled, predicts epigenetic fate of promoter CpG islands.
Cell line
View SamplesBoron is essential for plants, and boron availability in soil is an important determinant of agricultural production. Boron availability in soil is limited at many regions in the world, including Japan. Under boron deficient conditions, leaf expansion and root elongation, apical dominance, flower development,and fruit and seed sets are inhibited.
The Minimum Open Reading Frame, AUG-Stop, Induces Boron-Dependent Ribosome Stalling and mRNA Degradation.
Age, Specimen part, Treatment
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Dynamically and epigenetically coordinated GATA/ETS/SOX transcription factor expression is indispensable for endothelial cell differentiation.
Specimen part, Time
View SamplesAlthough differentiation of mice embryonic stem cells into vascular endothelial cells (ECs) gives a model for investigating molecular mechanisms of vascular development in vivo, temporal dynamics of gene expressions and chromatin modifications have not been studied until now. Here, we interrogated transcriptome and two histone modifications, H3K4me3 and H3K27me3, with a genome-wide scale during ECs differentiation and elucidated epigenetic switch peculiar to ECs. We find Gata2, Fli1, Sox7, and Sox18 are master regulators from genetic and epigenetic data, these genes were induced after Etv2 activation. These genes have specific histone modification pattern which is repressed by H3K27me3 modification at Flk-sorted mesoderm and changed to the bivalent (H3K4me3 and H3K27me3 both positive) state rapidly after vascular endothelial cells growth factor (VEGF) stimuli. Using a previously reported ECs differentiation model, we demonstrate that four transcription factors are critical for ECs specific gene expressions and efficient differentiation. Moreover, from knockdown experiments using si-RNA, we discovered these factors inhibited not only TGF signaling pathway, that is endothelial mesenchymal transition pathway, but also other near lineage commitment, including blood cells, skeletal muscle cells, vascular smooth muscle cells, and cardiomyocytes. We further identify each factor specific target genes during ECs differentiation by microarray, including both activating and repressing genes. Together, our findings from a detailed epigenetic approach provide a basic understanding temporal regulated chromatin signatures and resulting gene expression profile during ECs commitment, which is applicable to other models of differentiation and production of mature and long lasting ECs for regenerative medicine.
Dynamically and epigenetically coordinated GATA/ETS/SOX transcription factor expression is indispensable for endothelial cell differentiation.
Specimen part
View Samples