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SRP126861
Homo sapiens
11 Downloadable Samples
Illumina HiSeq 2500
Description
Background – Epigenetic alterations are stable modifications to chromatin structure that occur in response to environmental cues such as hypoxia or altered nutrient delivery. DNA methylation is a well-established and dynamic DNA modification that contributes to the regulation of gene expression. In the current study, we test the hypothesize that ischemic heart failure is defined by a distinct signature of DNA methylation that corresponds with altered expression of genes involved in cardiac ventricular dysfunction. Methods and Results – Using a methylation array, we quantified genome-wide DNA methylation of endomyocardial samples acquired from patients with ischemic (n = 6) or non-ischemic (n = 5) heart failure. RNA-sequencing analysis was performed in the same samples to identify transcriptomic changes (Fold Change > 1.5, Q < 0.05, FPKM > 2) associated with differential methylation (|Percent Change| > 5%, p < 0.05). Of the promoter-associated CpG Islands, which are well-established regions of negative transcriptional regulation, we identified a signature of robust hypermethylation. The methylation changes linked to significantly decreased transcripts included key fatty acid metabolic regulators (e.g. KLF15, AGPAT9, APOA1, and MXD4). Among the few hypomethylated and induced genes was PFKFB3, which encodes for the rate-limiting enzyme of glycolysis. Gene set enrichment analysis identified TGFß as a nodal upstream regulator of the methylation changes, potentially supporting a role of DNA methylation in the increased fibrosis and apoptosis that accompanies ischemic heart failure. Conclusions – Our data identify that the DNA methylation signature recapitulates the pathologic hallmarks of ischemic heart failure. Furthermore, we show that differential DNA methylation of CpG islands within the promoter depict alterations in metabolic substrate utilization known to occur in ischemic heart failure, and may govern a return to the fetal-like metabolic program. Overall design: RNA Sequencing analysis of left ventricle samples in 11 subjects with end-stage heart failure.
Publication Title
Genome-wide DNA methylation encodes cardiac transcriptional reprogramming in human ischemic heart failure.
Sample Metadata Fields
Sex, Age, Race, Subject
View Samples- Mus musculus
- 13 Downloadable Samples
Affymetrix Mouse Genome 430 2.0 Array (mouse4302)
Description
Long recognized as an evolutionarily ancient cell type involved in tissue homeostasis and immune defense against pathogens, macrophages are being rediscovered as regulators of several diseases including cancer. Here we show that in mice, mammary tumor growth induces the accumulation of tumor-associated macrophages (TAMs) that are phenotypically and functionally distinct from mammary tissue macrophages (MTMs). TAMs express the adhesion molecule Vcam1 and proliferate upon their differentiation from inflammatory monocytes, but do not exhibit an alternatively activated phenotype. TAM differentiation depends on the transcriptional regulator of Notch signaling, RBPJ; and TAM, but not MTM, depletion restores tumor-infiltrating cytotoxic T cell responses and suppresses tumor growth. These findings reveal the ontogeny of TAMs and a discrete tumor-elicited inflammatory response, which may provide new opportunities for cancer immunotherapy.
Publication Title
The cellular and molecular origin of tumor-associated macrophages.
Sample Metadata Fields
Age, Specimen part
View Samples- Mus musculus
- 4 Downloadable Samples
- Affymetrix Mouse Gene 2.1 ST Array (mogene21st)
Description
The murine thymus produces discrete T cell subsets making either IFN- or IL-17, but the role of the TCR in this developmental process remains controversial. Here we generated a non-transgenic and polyclonal model of reduced TCR expression and signal strength selectively on T cells. Mice haploinsufficient for both CD3 and CD3 (CD3DH) showed normal thymocyte subsets but specific defects in T cell development, namely impaired differentiation of IL-17-producing embryonic V6+ (but not adult V4+) T cells and a marked depletion of IFN--producing CD122+ NK1.1+ (V1-biased) T cells throughout life. As result, adult CD3DH mice showed defective peripheral IFN- responses and were resistant to experimental cerebral malaria. Thus, strong TCR signaling is required within specific developmental windows with distinct V usage and differential cytokine production by effector T cell subsets.
Publication Title
TCR signal strength controls thymic differentiation of discrete proinflammatory γδ T cell subsets.
Sample Metadata Fields
Specimen part
View Samples- Homo sapiens
- 99 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
The introduction of microarray techniques to cancer research brought great expectations for finding biomarkers that would improve patients treatment; however, the results of such studies are poorly reproducible and critical analyses of these methods are rare. In this study, we examined global gene expression in 97 ovarian cancer samples. Also, validation of results by quantitative RT-PCR was performed on 30 additional ovarian cancer samples. We carried out a number of systematic analyses in relation to several defined clinicopathological features. The main goal of our study was to delineate the molecular background of ovarian cancer chemoresistance and find biomarkers suitable for prediction of patients prognosis. We found that histological tumor type was the major source of variability in genes expression, except for serous and undifferentiated tumors that showed nearly identical profiles. Analysis of clinical endpoints [tumor response to chemotherapy, overall survival, disease-free survival (DFS)] brought results that were not confirmed by validation either on the same group or on the independent group of patients. CLASP1 was the only gene that was found to be important for DFS in the independent group, whereas in the preceding experiments it showed associations with other clinical endpoints and with BRCA1 gene mutation; thus, it may be worthy of further testing. Our results confirm that histological tumor type may be a strong confounding factor and we conclude that gene expression studies of ovarian carcinomas should be performed on histologically homogeneous groups. Among the reasons of poor reproducibility of statistical results may be the fact that despite relatively large patients group, in some analyses one has to compare small and unequal classes of samples. In addition, arbitrarily performed division of samples into classes compared may not always reflect their true biological diversity. And finally, we think that clinical endpoints of the tumor probably depend on subtle changes in many and, possibly, alternative molecular pathways, and such changes may be difficult to demonstrate.
Publication Title
Gene expression analysis in ovarian cancer - faults and hints from DNA microarray study.
Sample Metadata Fields
No sample metadata fields
View Samples- Homo sapiens
- 12 Downloadable Samples
- Affymetrix Human Transcriptome Array 2.0 (hta20)
Description
This SuperSeries is composed of the SubSeries listed below.
Publication Title
Histone methyltransferase DOT1L coordinates AR and MYC stability in prostate cancer.
Sample Metadata Fields
Specimen part, Cell line, Treatment
View Samples- Homo sapiens
- 12 Downloadable Samples
Affymetrix Human Transcriptome Array 2.0 (hta20)
Description
We performed expression profiling of prostate cancer cells, LNCaP and PC3 cells that were treated with the specific DOT1L inhibitor EPZ004777 (1uM) for 8 days. We found that unique genes were differentially expressed in both cell lines.
Publication Title
Histone methyltransferase DOT1L coordinates AR and MYC stability in prostate cancer.
Sample Metadata Fields
Specimen part, Cell line, Treatment
View Samples- Homo sapiens
- 114 Downloadable Samples
- Illumina HumanHT-12 V4.0 expression beadchip
Description
We report genomic analysis of 300 meningiomas, the most common primary brain tumors, leading to the discovery of mutations in TRAF7, a proapoptotic E3 ubiquitin ligase, in nearly one-fourth of all meningiomas. Mutations in TRAF7 commonly occurred with a recurrent mutation (K409Q) in KLF4, a transcription factor known for its role in inducing pluripotency, or with AKT1(E17K), a mutation known to activate the PI3K pathway. SMO mutations, which activate Hedgehog signaling, were identified in ~5% of non-NF2 mutant meningiomas. These non-NF2 meningiomas were clinically distinctive-nearly always benign, with chromosomal stability, and originating from the medial skull base. In contrast, meningiomas with mutant NF2 and/or chromosome 22 loss were more likely to be atypical, showing genomic instability, and localizing to the cerebral and cerebellar hemispheres. Collectively, these findings identify distinct meningioma subtypes, suggesting avenues for targeted therapeutics.
Publication Title
Genomic analysis of non-NF2 meningiomas reveals mutations in TRAF7, KLF4, AKT1, and SMO.
Sample Metadata Fields
Disease stage
View Samples