In order to characterize the differences between second trimester Down syndrome (DS) and euploid fetuses, we compared gene expression in uncultured amniotic fluid supernatant samples. We identified individually differentially expressed genes via paired t-tests in the matched samples, and a set of differentially expressed genes on chromosome 21 using Gene Set Enrichment Analysis. Functional pathway analysis of the resulting genes highlighted the importance of oxidative stress, ion transport, and G-protein signaling in the DS fetuses.
Functional genomic analysis of amniotic fluid cell-free mRNA suggests that oxidative stress is significant in Down syndrome fetuses.
Sex, Specimen part
View SamplesThe discovery of fetal mRNA transcripts in maternal circulation holds great promise for noninvasive prenatal diagnosis. To identify potential fetal biomarkers, we studied whole blood and plasma transcripts common to term pregnant women and their newborns but reduced or absent in the postpartum mothers.
Gene expression analysis in pregnant women and their infants identifies unique fetal biomarkers that circulate in maternal blood.
Specimen part
View SamplesCells were isolated from healthy human donors (n=2). Unstimulated cells. Cells were stained with CD4, CD45RA, CCR7 and CXCR7. Using flow cytometry, 4 CD4+ T cell populations were sorted: (1) Nave (CD45RA+CCR7+CXCR5-), (2) Central memory (CD45RA-CCR7+CXCR5-), (3) Effector memory (CD45RA-CCR7-CXCR5-) and (4) CXCR5+ cells (CD45RA-CCR7-CXCR5+)
CXCR5 expressing human central memory CD4 T cells and their relevance for humoral immune responses.
Specimen part
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Epigenomic enhancer profiling defines a signature of colon cancer.
Specimen part
View SamplesCancer is characterized by gene expression aberrations. Studies have largely focused on coding sequences and promoters, despite the fact that distal regulatory elements play a central role in controlling transcription patterns. Here we utilize the histone mark H3K4me1 to analyze gain and loss of enhancer activity genome wide in primary colon cancer lines relative to normal colon crypts. We identified thousands of variant enhancer loci (VELs) that comprise a signature that is robustly predictive of the in vivo colon cancer transcriptome. Furthermore, VELs are enriched in haplotype blocks containing colon cancer genetic risk variants, implicating these genomic regions in colon cancer pathogenesis. We propose that reproducible changes in the epigenome at enhancer elements drive a unique transcriptional program to promote colon carcinogenesis.
Epigenomic enhancer profiling defines a signature of colon cancer.
Specimen part
View SamplesPilocytic astrocytoma is the most common type of brain tumor in pediatric population, generally connected with favorable prognosis, although recurrences or dissemination sometimes are also observed. For tumors originating in supra- or infratentorial location different molecular background was suggested but plausible correlations between transcriptional profile and radiological features and/or clinical course are still undefined. The purpose of this study was to identify gene expression profiles related to the most frequent locations of this tumor, subtypes based on various radiological features and clinical pattern of the disease. According to the radiological features presented on MRI, all cases were divided into four subtypes: solid or mainly solid, cystic with an enhancing cyst wall, cystic with a non-enhancing cyst wall and solid with central necrosis. Bioinformatic analyses showed that gene expression profile of pilocytic astrocytoma highly depends on the tumor location. Most prominent differences were noted for IRX2, PAX3, CXCL14, LHX2, SIX6, CNTN1 and SIX1 genes expression which could distinguish pilocytic astrocytomas of different location even within supratentorial region. Analysis of the genes potentially associated between radiological features showed much weaker transcriptome differences. Single genes showed association with the tendency to progression. Here we showed that pilocytic astrocytomas of three different locations could be precisely differentiated on the basis of gene expression level but their transcriptional profiles did not strongly reflect the radiological appearance of the tumor or the course of the disease.
Transcriptional profiles of pilocytic astrocytoma are related to their three different locations, but not to radiological tumor features.
Sex, Age, Specimen part, Disease
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Preferential Iron Trafficking Characterizes Glioblastoma Stem-like Cells.
Cell line
View SamplesGlioblastomas display hierarchies with self-renewing cancer stem-like cells (CSCs). RNA sequencing and enhancer mapping revealed regulatory programs unique to CSCs causing upregulation of the iron transporter transferrin, the top differentially expressed gene compared to tissue-specific progenitors. Direct interrogation of iron uptake demonstrated CSCs potently extract iron from the microenvironment more effectively than other tumor cells. Systematic interrogation of iron flux determined that CSCs preferentially require transferrin receptor and ferritin - two core iron regulators - to propagate and form tumors in vivo. Depleting ferritin disrupted CSC mitotic progression, through the STAT3-FoxM1 regulatory axis, revealing an iron-regulated CSC pathway. Iron is a unique, primordial metal fundamental for earliest life forms, and on which CSCs have an epigenetically programmed, targetable dependence.
Preferential Iron Trafficking Characterizes Glioblastoma Stem-like Cells.
Cell line
View SamplesGlioblastomas display hierarchies with self-renewing cancer stem-like cells (CSCs). RNA sequencing and enhancer mapping revealed regulatory programs unique to CSCs causing upregulation of the iron transporter transferrin, the top differentially expressed gene compared to tissue-specific progenitors. Direct interrogation of iron uptake demonstrated CSCs potently extract iron from the microenvironment more effectively than other tumor cells. Systematic interrogation of iron flux determined that CSCs preferentially require transferrin receptor and ferritin - two core iron regulators - to propagate and form tumors in vivo. Depleting ferritin disrupted CSC mitotic progression, through the STAT3-FoxM1 regulatory axis, revealing an iron-regulated CSC pathway. Iron is a unique, primordial metal fundamental for earliest life forms, and on which CSCs have an epigenetically programmed, targetable dependence. Overall design: RNA-seq of primary patient-derived GBM cancer stem cells and normal human neural progenitor cells
Preferential Iron Trafficking Characterizes Glioblastoma Stem-like Cells.
No sample metadata fields
View SamplesWe have analyzed, using DNA microarrays, putative differences in gene-expression level between hereditary BRCA1 mutation-linked and sporadic breast cancer. Our results show that a previously reported marked difference between BRCA1-mutation linked and sporadic breast cancer was probably due to uneven stratification of samples with different ER status and basal-like versus luminal-like subtype. We observed that apparent difference between BRCA1-linked and other types of breast cancer found in univariate analysis was diminished when data were corrected for ER status and molecular subtype in multivariate analyses. In fact, the difference in gene expression pattern of BRCA1-mutated and sporadic cancer is very discrete. These conclusions were supported by the results of Q-PCR validation. We also found that BRCA1 gene inactivation due to promoter hypermethylation had similar effect on general gene expression profile as mutation-induced protein truncation. This suggests that in the molecular studies of hereditary breast cancer, BRCA1 gene methylation should be recognized and considered together with gene mutation.
BRCA1-related gene signature in breast cancer: the role of ER status and molecular type.
Age
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