Filters
Technology
Platform
SRP011378
Homo sapiens
3 Downloadable Samples
Illumina Genome Analyzer II
Description
In adult cancers, epigenetic changes and aberrant splicing of the DNMT3B is commonly observed, and the pattern of gene methylation and expression has been shown to be modified by DNMT3B7, a truncated protein of DNMT3B. Much less is known about the mechanism of epigenetic changes in the pediatric cancer neuroblastoma. To investigate if aberrant DNMT3B transcripts alter DNA methylation, gene expression and tumor phenotype in neuroblastoma, we measured DNMT3B isoform expression in primary tumors and cell lines. Higher levels of DNMT3B7 were detected in differentiated ganglioneuroblastomas compared to undifferentiated neuroblastomas, suggesting that expression of DNMT3B7 may induce a less clinically aggressive tumor phenotype. To test this hypothesis, we investigated the effects of forced DNMT3B7 in neuroblastoma cells. We found that DNMT3B7 expression significantly inhibited neuroblastoma cell proliferation in vitro, and in neuroblastoma xenografts, DNMT3B7 decreased angiogenesis and tumor growth. DNMT3B7-positive cells had higher levels of total genomic methylation, and RNA-sequencing revealed a dramatic decrease in expression of FOS and JUN family members, AP1 complex components. Consistent with the established antagonistic relationship between AP1 expression and retinoic acid receptor activity, decreased proliferation and increased differentiation was seen in the DNMT3B7-expressing neuroblastoma cells following treatment with all trans retinoic acid (ATRA) compared to controls. Our results demonstrate that high levels of DNMT3B7 modify the epigenome in neuroblastoma cells, induce changes in gene expression, inhibit tumor growth, and increase sensitivity to ATRA. Further knowledge regarding mechanisms by which DNMT3B7 regulates gene methylation may ultimately lead to the development of therapeutic strategies that reverse the epigenetic aberrations that drive neuroblastoma pathogenesis. Overall design: DNMT3B7, a truncated DNMT3B isoform, was stably transfected into an N-type neuroblastoma cell line (LA1-55n) using a Tet-off inducible system. DNMT3B7 expressing cells were compared to vector control cells after 21 days of induction.
Publication Title
Truncated DNMT3B isoform DNMT3B7 suppresses growth, induces differentiation, and alters DNA methylation in human neuroblastoma.
Sample Metadata Fields
Cell line, Subject
View Samples- Triticum aestivum
- 10 Downloadable Samples
Affymetrix Wheat Genome Array (wheat)
Description
affy_seed_kinetic_wheat - affy_seed_kinetic_wheat - Study gene expression during the grain developmental -The aim of the study is to identify the genes that are differentially expressed during the grain development in wheat.-Study gene expression during the grain developmental Sample at 100 degree days, year 2004 and 2006 Sample at 200 degree days, year 2004 and 2006 Sample at 250 degree days, year 2004 and 2006 Sample at 300 degree days, year 2004 and 2006 Sample at 400 degree days, year 2004 and 2006
Publication Title
RNA-seq in grain unveils fate of neo- and paleopolyploidization events in bread wheat (Triticum aestivum L.).
Sample Metadata Fields
No sample metadata fields
View Samples- Mus musculus
- 60 Downloadable Samples
- Affymetrix Mouse Genome 430 2.0 Array (mouse4302)
Description
Background: Information on the carcinogenic potential of chemicals is only availably for High Production Volume products. There is however, a pressing need for alternative methods allowing for the chronic toxicity of substances, including carcinogenicity, to be detected earlier and more reliably. Here we applied advanced genomics to a cellular transformation assay to identify gene signatures useful for the prediction of risk for carcinogenicity. Methods: Genome wide gene expression analysis and qRT-PCR were applied to untransformed and transformed Balb/c 3T3 cells that exposed to 2, 4-diaminotoluene (DAT), benzo(a)pyrene (BaP), 2-Acetylaminoflourene (AAF) and 3-methycholanthrene (MCA) for 24h and 120h, at different concentrations, respectively. Furthermore, various bioinformatics tools were used to identify gene signatures predicting for the carcinogenic risk. Results: Bioinformatics analysis revealed distinct datasets for the individual chemicals tested while the number of significantly regulated genes increased with ascending treatment concentration of the cell cultures. Filtering of the data revealed a common gene signature that comprised of 13 genes whose regulation in cancer tissue has already been established. Strikingly, this gene signature was already identified prior to cell transformation therefore confirming the predictive power of this gene signature in identifying carcinogenic risks of chemicals. Comparison of fold changes determined by microarray analysis and qRT-PCR were in good agreement. Conclusion: Our data describes selective and commonly regulated carcinogenic pathways observed in an easy to use in vitro carcinogenicity assay. Here we defined a set of genes which can serve as a simply assay to predict the risk for carcinogenicity by use of an alternative in vitro testing strategy.
Publication Title
Toxicogenomics applied to in vitro carcinogenicity testing with Balb/c 3T3 cells revealed a gene signature predictive of chemical carcinogens.
Sample Metadata Fields
Cell line, Treatment, Time
View Samples- Homo sapiens
- 26 Downloadable Samples
- Affymetrix Human Genome U133A 2.0 Array (hgu133a2)
Description
Approximately 5% of all breast cancers can be attributed to an inherited mutation in one of two cancer susceptibility genes, BRCA1 and BRCA2. We searched for genes that have the potential to distinguish healthy BRCA1 and BRCA2 mutation carriers from non-carriers based on differences in expression profiling. Using expression microarrays we compared gene expression of irradiated lymphocytes from BRCA1 and BRCA2 mutation carriers versus control non-carriers. We identified 137 probe sets in BRCA1 carriers and 1345 in BRCA2 carriers with differential gene expression. Gene Ontology analysis revealed that most of these genes relate to regulation pathways of DNA repair processes, cell cycle regulation and apoptosis. Real-time PCR was performed on the 36 genes which were most prominently differentially expressed in the microarray assay; 21 genes were shown to be significantly differentially expressed in BRCA1 or BRCA2 mutation carriers as compared to controls (p<0.05). Based on a validation study with 40 mutation carriers and 17 non-carriers, a multiplex model that included six or more coincidental genes of 18 selected genes was constructed in order to predict the risk of carrying a mutation. The results using this model showed sensitivity 95% and specificity 88%. In summary, our study provides insight into the biological effect of heterozygous mutations in BRCA1 and BRCA2 genes in response to ionizing irradiation induced DNA damage. We also suggest a set of 18 genes that can be used as a prediction and screening tool for BRCA1 or BRCA2 mutational carriers by using easily obtained lymphocytes.
Publication Title
Determination of molecular markers for BRCA1 and BRCA2 heterozygosity using gene expression profiling.
Sample Metadata Fields
Specimen part
View Samples- Danio rerio
- 54 Downloadable Samples
- IlluminaHiSeq2000
Description
Development is a complex and well-defined process characterized by rapid cell proliferation and apoptosis. At this stage in life, a developmentally young organism is more sensitive to toxicants and other stressors when compared to an adult. In response to pro-oxidant exposure, members of the Cap’n’Collar (CNC) basic leucine zipper (b-ZIP) transcription factor family (including the Nfe2-related factors, Nrfs) activate the expression of genes that contribute to reduced toxicity. Here, we studied the role of the Nrf protein, Nfe2, in the developmental response to pro-oxidant exposure in the zebrafish. Following acute waterborne exposures to diquat or tert-buytlhydroperoxide (tBOOH) at three developmental stages, wildtype (WT) and nfe2 knockout (KO) embryos and larvae were morphologically scored and their transcriptomes sequenced. Overall design: Wildtype animals were on the AB background and an additional germline nfe2 knockout strain were created by disruption of the nfe2 reading frame. Waterborne exposures to either diquat or tBOOH were carried out at three different developmental stages: 2 hours post fertilization (hpf), 48hpf, and 96hpf in 3 pools of 30 embryos per condition. Animals were exposed to no treatment, 20µM diquat or 1mM tBOOH for a 4-hour dosing period. Total RNA was isolated from pooled animals and 50 bp, paired end, libraries were sequenced using the Illumina HiSeq 2000 platform, with approximately 25 million reads per sample. Reads were then aligned to the Ensembl GRCz10 zebrafish reference genome using Tophat2 and raw counts data normalized using DESeq2. Gene annotation was from Ensemble for GRCz10.
Publication Title
The transcription factor, Nuclear factor, erythroid 2 (Nfe2), is a regulator of the oxidative stress response during Danio rerio development.
Sample Metadata Fields
No sample metadata fields
View Samples- Homo sapiens
- 6 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
The level of trypsin-2 has been shown to correlate with the malignancy and metastatic potential of many cancer.
Publication Title
Trypsin-2 enhances carcinoma invasion by processing tight junctions and activating ProMT1-MMP.
Sample Metadata Fields
Specimen part, Cell line
View Samples- Mus musculus
- 30 Downloadable Samples
- Affymetrix Mouse Gene 2.1 ST Array (mogene21st)
Description
Up to now the role of tumor-specific pTregs and anergic cells during tumor development is not fully understood. Here we used a genetically-induced tumor expressing a MHC-II restricted DBY model antigen to characterize the tumor-induced pTregs and anergic cells that arise early during tumor development.
Publication Title
Induction of anergic or regulatory tumor-specific CD4<sup>+</sup> T cells in the tumor-draining lymph node.
Sample Metadata Fields
Time
View Samples- Mus musculus
- 15 Downloadable Samples
- Affymetrix Mouse Gene 2.1 ST Array (mogene21st)
Description
Up to know CD4 T cell antitumor responses have been mostly studied in transplanted tumor models. However, although they are valuable tools, they are not suitable to study the long term interactions between tumors and the immune system
Publication Title
Induction of anergic or regulatory tumor-specific CD4<sup>+</sup> T cells in the tumor-draining lymph node.
Sample Metadata Fields
Time
View Samples- Homo sapiens
- 10 Downloadable Samples
- Affymetrix Human Gene 2.1 ST Array (hugene21st)
Description
CD4+ T cells as mediators of antitumor responses are beginning to be appreciated. Our team demonstrated that chronically activated CD4+ T cells (chCD4+ T cells) were expanded in the blood of cancer patients and their expansion is correlated with tumor regression.
Publication Title
Induction of anergic or regulatory tumor-specific CD4<sup>+</sup> T cells in the tumor-draining lymph node.
Sample Metadata Fields
Disease
View Samples- Mus musculus
- 9 Downloadable Samples
- Affymetrix Mouse Expression 430A Array (moe430a)
Description
Spinal Muscular Atrophy (SMA) is an autosomal recessive motor neuron disease and is the second most common genetic disorder leading to death in childhood. Stem cell transplantation could represent a therapeutic approach for motor neuron diseases such as SMA. We examined the theraputics effects of a spinal cord neural stem cell population and their ability to modify SMA phenotype.
Publication Title
Neural stem cell transplantation can ameliorate the phenotype of a mouse model of spinal muscular atrophy.
Sample Metadata Fields
No sample metadata fields
View Samples