This SuperSeries is composed of the SubSeries listed below.
5-hydroxymethylcytosine marks promoters in colon that resist DNA hypermethylation in cancer.
Sex, Specimen part, Cell line, Treatment, Subject
View SamplesThe discovery of cytosine hydroxymethylation (5-hmC) as a mechanism that potentially controls DNA methylation changes typical of neoplasia prompted us to investigate its behavior in colon cancer. 5-hmC is globally reduced in proliferating cells such as colon tumors and the gut crypt progenitors, from which tumors can arise. Here, we show that colorectal tumors and cancer cells express Ten-Eleven Translocation (TET) transcripts at levels similar to normal tissues. Genome-wide analyses show that promoters marked by 5-hmC in normal tissue, and those identified as TET2 targets in colorectal cancer cells, are resistant to methylation gain in cancer. In vitro studies of TET2 in cancer cells confirm that these promoters are resistant to methylation gain independently of sustained TET2 expression. We also find that a considerable number of the methylation gain-resistant promoters marked by 5-hmC in normal colon overlap with those that are marked with poised bivalent histone modifications in embryonic stem cells. Together our results indicate that promoters that acquire 5-hmC upon normal colon differentiation are innately resistant to neoplastic hypermethylation by mechanisms that do not require high levels of 5-hmC in tumors. Our study highlights the potential of cytosine modifications as biomarkers of cancerous cell proliferation.
5-hydroxymethylcytosine marks promoters in colon that resist DNA hypermethylation in cancer.
Sex, Specimen part, Subject
View SamplesMutation or epigenetic silencing of the transcription factor C/EBP is observed in ~10% of patients with acute myeloid leukemia (AML). In both cases, a common global gene expression profile is observed, but down-stream targets relevant for leukemogenesis are not known. Here we identify Sox4 as a direct target of C/EBP whereby its expression is inversely correlated with C/EBP activity. Downregulation of Sox4 abrogated increased self-renewal of leukemic cells and restored their differentiation. Gene expression profiles of leukemia initiating cells (LICs) from both Sox4 overexpression and murine mutant C/EBP AML models clustered together, but differed from other types of AML. Our data demonstrate that Sox4 overexpression resulting from C/EBP inactivation contributes to the development of leukemias with a distinct LIC phenotype.
Sox4 is a key oncogenic target in C/EBPα mutant acute myeloid leukemia.
Specimen part
View SamplesPurpose: Presence of pelvic lymph node metastases is the main prognostic factor in early stage cervical cancer patients, primarily treated with surgery. Aim of this study was to identify cellular tumor pathways associated with pelvic lymph node metastasis in early stage cervical cancer.
Involvement of the TGF-beta and beta-catenin pathways in pelvic lymph node metastasis in early-stage cervical cancer.
Age
View Samplesgamma delta intraepithelial lymphocytes were isolated from the colons of DSS-treated and untreated mice. Total RNAs were isolated and compared by Affymetrix DNA microarray.
Reciprocal interactions between commensal bacteria and gamma delta intraepithelial lymphocytes during mucosal injury.
No sample metadata fields
View SamplesThe GntR-like protein NorG has been shown to affect Staphylococcus aureus genes involved in the resistance to quinolones and beta-lactams such as those encoding the NorB and AbcA transporters. To identify the target genes regulated by NorG, we carried out transcriptional profiling assays using S. aureus RN6390 and its isogenic norG::cat mutant. Our data showed that NorG positively affected the transcription of global regulators mgrA, arlS, and sarZ. The three putative drug efflux pump genes most positively affected by NorG were the NorB efflux pump (5.1-fold), the MmpL-like protein SACOL2566 (5.2-fold), and the BcrA-like drug transporter SACOL2525 (5.7-fold). The S. aureus predicted MmpL protein showed 53% homology with the MmpL lipid transporter of Mycobacterium tuberculosis, and the putative SACOL2525 protein showed 87% homology with the bacitracin drug transporter BcrA of Staphylococcus hominis. Two pump genes most negatively affected by NorG were NorC (4-fold) and AbcA (6-fold). Other categories of genes such as those participating in amino acid, inorganic ion, or nucleotide transporters and metabolism, were also affected by NorG. Real-time RT-PCR assays for mgrA, arlS, sarZ, norB, norC, abcA, mmpL, and bcrA-like were carried out to verify microarray data and showed the same level of up- or down regulation by NorG. The norG mutant showed a twofold increase in the resistance to norfloxacin and rhodamine, both substrates of the NorC transporter, which is consistent with the resistance phenotype conferred by overexpression of norC on a plasmid. These data indicate that NorG has broad regulatory function in S. aureus.
Transcriptional profiling analysis of the global regulator NorG, a GntR-like protein of Staphylococcus aureus.
No sample metadata fields
View SamplesThis study delineated how small intestinal resident microflora impact gene expression in Paneth cells.
Symbiotic bacteria direct expression of an intestinal bactericidal lectin.
No sample metadata fields
View SamplesMedulloblastoma is the most common form of malignant paediatric brain tumour and is the leading cause of childhood cancer related mortality. The four molecular subgroups of medulloblastoma that have been identified WNT, SHH, Group 3 and Group 4 - have molecular and topographical characteristics suggestive of different cells of origin. Definitive identification of the cell(s) of origin of the medulloblastoma subgroups, particularly the poorer prognosis Group 3 and Group 4 medulloblastoma, is critical to understand the pathogenesis of the disease, and ultimately for the development of more effective treatment options.
Gene expression analyses of the spatio-temporal relationships of human medulloblastoma subgroups during early human neurogenesis.
Sex, Age
View SamplesThis investigation provides a robust multi-dimensional compendium of gene expression data relevant to mouse facial development. It profiles the transcriptome ofectoderm and mesenchyme from the three facial prominences in a time series encompassing their growth and fusion. Analysis of the dataset identified more than 8000 differentially expressed genes comprising dramatically different ectoderm and mesenchyme programs. The mesenchyme programs included many genes identified in earlier analyses as well hundreds of genes not previously implicated in craniofacial development. The ectoderm programs included over a thousand genes that highlight epithelial structure, cell-cell interactions and signaling.
Systems biology of facial development: contributions of ectoderm and mesenchyme.
Specimen part
View SamplesNeo/null loss of Tfap2a in E10.5 mouse facial prominences
Tfap2a-dependent changes in mouse facial morphology result in clefting that can be ameliorated by a reduction in Fgf8 gene dosage.
Specimen part
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