Treatment-related DNA hypermethylation may play a role in creating drug resistant phenotypes by inactivating genes that are required for cytotoxicity, but there have been no genome-wide studies to systematically investigate methylation of individual genes following exposure to chemotherapy.
Identification of hypermethylated genes associated with cisplatin resistance in human cancers.
Specimen part, Cell line
View SamplesSilencing of tumor suppressor genes plays a vital role in head and neck carcinogenesis. Aberrant hypermethylation in the promoter region of some known or putative tumor suppressor genes (TSGs) occurs frequently during the development of various cancers including head and neck squamous cell carcinoma (HNSCC). In this study we used an expanded mRNA expression profiling approach followed by microarray expression analysis to identify epigenetically inactivated genes in HNSCC. Two HNSCC cell lines were treated with 5-aza-2-deoxycytidine followed by microarray analysis to identify epigenetically silenced genes in HNSCC. 1960, 614, and 427 genes were upregulated in HNSCC cell lines JHU-012, JHU-011 and the combination of both cell lines, respectively. HNSCC tumor and normal mucosal samples were used for gene profiling by a 47K mRNA gene expression array and we found, 7140 genes were downregulated in HNSCC tumors compared to normal mucosa as determined by microarray analysis and were integrated with cell line data. Integrative analysis defined 126 candidate genes, of which only seven genes showed differentially methylation in tumors and no methylation in normal mucosa after bisulfite sequencing. After validation by QMSP, one gene, GNG7, was confirmed as being highly methylated in tumors and unmethylated in normal mucosal and salivary rinse samples demonstrating cancer-specific methylation in HNSCC tissues. TXNIP and TUSC2 were partially methylated in tumors and normal salivary rinses but unmethylated in normal mucosa. We concluded GNG7 as a highly specific promoter methylated gene associated with HNSCC. In addition, TXNIP and TUSC2 are also potential biomarkers for HNSCC.
Identification of guanine nucleotide-binding protein γ-7 as an epigenetically silenced gene in head and neck cancer by gene expression profiling.
Sex
View SamplesWe report here mRNA-seq data of wild-type and Nat4-deletion mutant yeast cells. We also report mRNA-seq data of wild-type yeast cells grown under non-calorie restriction (NCR) and calorie restriction (CR) conditions. Overall design: Comparison of differential gene-expression changes detected in Nat4-deletion mutant and cells grown in calorie restriction
Loss of Nat4 and its associated histone H4 N-terminal acetylation mediates calorie restriction-induced longevity.
Cell line, Subject
View SamplesThis SuperSeries is composed of the SubSeries listed below.
RNA Pol II accumulates at promoters of growth genes during developmental arrest.
No sample metadata fields
View SamplesWhen C. elegans larvae hatch in the absence of food they persist in a stress resistant, developmentally arrested state (L1 arrest). We characterized mRNA expression genome-wide in a pair of bifurcating time series starting in the late embryo and proceeding through the hatch in the presence and absence of food (E. coli).
RNA Pol II accumulates at promoters of growth genes during developmental arrest.
No sample metadata fields
View SamplesDespite timely and successful surgery, 32% of patients with bilateral and 10% with unilateral cryptorchidism will develop azoospermia. Cryptorchid boys at risk of azoospermia display a typical testicular histology of impaired mini-puberty at the time of the orchidopexy.
Testicular gene expression in cryptorchid boys at risk of azoospermia.
Specimen part
View SamplesSkeletal muscle senescence influences whole organism aging, yet little is known on the relay of pro-longevity signals from muscles to other tissues. We performed an RNAi screen in Drosophila for muscle-released cytokines (?myokines?) regulating lifespan and identified Myoglianin, the homolog of human Myostatin. Myoglianin is induced in skeletal muscles by the transcription factor Mnt and together they constitute an inter-organ signaling module that regulates lifespan, age-related muscle dysfunction, and protein synthesis across aging tissues. Both Mnt and Myoglianin activate already in young age the protective decline in protein synthesis that is typical of old age, while knock-down of Myoglianin impairs this process. Mechanistically, Mnt decreases the expression of nucleolar components in muscles while also decreasing nucleolar size in distant tissues via Myostatin/p38 MAPK signaling. Our results highlight a myokine-dependent inter-organ longevity pathway that coordinates nucleolar function and protein synthesis across aging tissues.
Intertissue control of the nucleolus via a myokine-dependent longevity pathway.
Sex, Specimen part, Treatment
View SamplesWe analyzed gene expression in human fibroblasts stimulated by platelet-derived growth factor-BB (PDGF-BB) or basic fibroblast growth factor (bFGF) for 1h and 24h. The results of two independent experiments were merged. SAM analysis identified 116 relevant probe sets. Hierarchical clustering of these probe sets showed divergent early gene regulation by PDGF and FGF but overlapping late response. We first analyzed genes commonly regulated by PDGF-BB and b-FGF more than 2 fold after 24h of stimulation and we found that these two growth factors repressed FOXO.
The transcription of FOXO genes is stimulated by FOXO3 and repressed by growth factors.
No sample metadata fields
View SamplesWe are investigating the transcriptional response of yeast to treatment with enediynes or gamma radiation, which generate different extents of double or single strand breaks in DNA.
The DNA-damage signature in Saccharomyces cerevisiae is associated with single-strand breaks in DNA.
No sample metadata fields
View SamplesThis study set out to identify MLX transcriptional targets in muscle cells. C2C12 Myoblasts were virally transduced to increase MLX activity, by overexpression of the wild-type protein; and to decrease MLX activity by overexpression of a dominant negative MLX protein and by shRNA induced knockdown of MLX. Transcripts that were significantly and consistently regulated by the different modes of MLX modulation were identified. The largest proportion of these were genes encoding secreted proteins including growth factors, cytokines and extracellular proteins. We therefore conclude that MLX can regulate myokine transcripts. Overall design: mRNA profiles from C2C12 muscle cells with increased and decreased MLX activity were examined.
The glucose-sensing transcription factor MLX promotes myogenesis via myokine signaling.
No sample metadata fields
View Samples